WO1999007202A1 - Pedestrian-controlled, portable cutter bar mower - Google Patents

Abstract

The invention relates to a pedestrian-controlled, portable cutter bar mower (1), comprising a guide pipe (6) with a gearhead (5) at one end (13) for driving a cutter bar (4), said cutter bar being mounted crosswise to the guide pipe (6), and a driving motor (3) at the other end (14). A shaft located in the guide pipe (6) provides the drive connection between the gearhead (5)and the motor (3). At least one handle (10, 11) for carrying and guiding the cutter bar mower (1) is also provided on the guide pipe (6). Spacers (20, 21) are provided for setting the cutting height (h) of the cutter bar (4). According to the invention, the spacer is located in the area of the gearhead (5) and the cutter bar (4) should be mounted in an axial position in relation to the front face of the spacer (20) and positioned inside the rolling circle (50) of said spacer (20). This provides an non-interlocking means of support which nonetheless performs well.

Description

 Walk-behind, portable bar mower

The invention relates to a handheld, portable bar mower according to the preamble of claim 1.

Such a bar mower is known from German utility model 19 40 337. It essentially consists of a guide tube that has a gear head at one end for driving a cutter bar lying transverse to the guide tube and at the other end a drive motor designed as a two-stroke engine, which is drive-connected to the gear head via a shaft mounted in the guide tube. The guide tube is closed at its upper end in an arc and forms a handle for carrying and guiding the bar mower. At the lower end, the guide tube carries support wheels behind the cutter bar in the feed direction, which cooperate with flexible support runners arranged on the right and left of the cutter bar. This bar mower is quite heavy and due to the four front support points also quite immobile. In order to drive over obstacles or the like, the log mower must regularly be completely lifted off the ground and carried over the obstacle.

The invention has for its object to provide a bar mower of the generic type in such a way that it enables functional mowing with high usability and easy construction even in difficult terrain. The object is achieved according to the characterizing features of claim 1.

Since the spacer is arranged in the area of the gear head, the cutter bar is supported approximately at the level of its longitudinal axis; this allows a great mobility of the cutter bar without the user having to carry the cutter bar permanently. Since the cutter bar - preferably together with the gear head - lies within the contour of a given or imaginary rolling circle of the spacer, it can easily be maneuvered over obstacles without lifting the spacers from the ground, which allows fatigue-free guiding, especially in large-scale work.

The cutter bar protrudes from the gear head to one side of the guide tube, the other end of the cutter bar being able to carry a support element. Since the spacer is provided in the area of the gear head, the weight of the bar mower is supported, but the free arm of the cutter bar is not hindered. The knife bar can cantileverly pass under obstacles, so that clean work is possible even in difficult areas such as building edges, guardrails, fences, trees and the like.

The spacer is expediently a wheel, a roller or the like. Rolling element, the axis of rotation of which coincides approximately with the longitudinal axis of the cutter bar and the diameter of which expediently determines a physical rolling circle. A docked fictitious rolling circle is also sufficient and can be determined by the fact that several diameter smaller roller elements are arranged next to one another on a partial circumference of the imagined rolling circle. The Spacer is provided between the cutter bar and the gear head.

In one embodiment, the bar mower is provided in the area of the gear head with a second spacer, which is at a distance from the longitudinal axis of the cutter bar and thus also from the first spacer. An imaginary connecting line between the spacers forms an angle with the longitudinal axis of the cutter bar, which is open to the free end of the cutter bar. A cutting height adjustment can be achieved by shifting the height of the guide tube, the projecting free end having the largest adjustment range in relation to the end of the cutter bar which is close to the gear head.

Further features of the invention result from the further claims, the description and the drawing, in which exemplary embodiments of the invention described in detail below are shown. Show it:

1 is a schematic plan view of a hand-held, portable bar mower,

2 is an enlarged view of a top view of the cutter bar,

3 is a side view of the schematic representation of the cutter bar according to FIG. 2,

4 shows a bar mower from the perspective of an operator, 5 is a perspective view of a spacer designed as a wheel between the cutter bar and gear head,

6 shows an enlarged view of a cutter bar with a roller arranged between the gear head and cutter bar as a spacer,

7 is an end view of the cutter bar with roller according to FIG. 6,

8 is a side view of a spacer constructed from a plurality of rollers,

9 is a plan view of the spacer arranged between the gear head and the cutter bar,

Fig. 10 is a side view of a

Iniineskater's spacer,

11 is a plan view of the spacer according to FIG. 10 in different mounting locations,

12 is an enlarged side view of a spacer composed of rollers and runners,

13 is a side view of a bar mower,

14 is a view of the bar mower according to FIG. 13 with different embodiments of the guide tube shown schematically, 15 is a perspective view of a free end of a cutter bar with support element,

15a is a view of a support element,

15b is a view of a solid support element for both directions of work,

16 is a view of a radför-shaped support element,

17 is a perspective view of a handle bar.

In the exemplary embodiment according to FIG. 1, a hand-guided, portable bar mower 1 is shown, which essentially consists of a guide tube 6 with a drive motor 3 arranged at one end 14 and a gear head 5 arranged at its other end 13, which drives a cutter bar 4. The drive motor 3 can be an internal combustion engine (two-stroke engine, four-stroke engine) or an electric motor. The cutter bar 4 extends freely cantilevered from the gear head 5 transversely to the guide tube 6, the longitudinal axis 16 of the cutter bar 4 lying approximately at right angles to the guide tube 6 in the exemplary embodiment. The cutter bar 4 essentially consists of a guide bar 17, on the two longitudinal sides of which reciprocating knives 18 are arranged in the direction of the arrow 19.

In the exemplary embodiment according to FIG. 1, the bar mower is worn by a user 2 by means of a carrying belt (not shown in more detail). To guide the bar mower, a handlebar 9 is connected transversely to the guide tube 6; the two ends of the handlebar 9 form a first handle 10 and a second handle 11. In order to support the gear head 5 on the ground, a spacer is provided in its area, which is expediently designed as a wheel 20 in the exemplary embodiment according to FIG. 1. The wheel 20 preferably supports the cutter bar 4 approximately at the level of its longitudinal axis 16, the free end 8 of the cutter bar 4 being freely height-adjustable if the bar mower is appropriately guided by the user 2. The cutter bar 4 is tilted by the user 2 around the contact surface of the wheel 20 via the handlebar 9. For mowing, the gear head 5 with the rolling spacer designed as a wheel 20 is placed on the ground and guided by the user 2 in the direction of the double arrow 7. The axial arrangement of the cutter bar 4 on an end face of the rolling spacer 20 and the size of the maximum rolling circle 50 of the diameter D such that the contour of the cutter bar 4 lies within the rolling circle 50 ensures good guidance of the cutter bar 1 even on uneven, rough terrain over the bottom. If the cutter bar 4 - as shown - is equipped on both long sides with preferably opposing cutting blades 18, mowing is possible both when pushing and when pulling the cutter bar 1. The cutting plane 30 determined by the cutter bar 4 lies approximately horizontally or approximately parallel to the floor 37. In a simple other embodiment, a knife arrangement on one long side of the cutter bar 4 can be sufficient, which can also consist of a fixed and a moving knife.

1, the axis of rotation 22 of the wheel 20 coincides with the longitudinal axis 16 of the cutter bar 4 in a plan view. The axis of rotation 22 is preferably coaxial with the longitudinal axis 16 of the cutter bar 4, for which purpose the gear head 5 expediently has an axle journal 23, which in the exemplary embodiment according to FIG the cutter bar 4 facing away from the gear head 5 is formed.

In the embodiment shown in FIGS. 2 and 3, the axis of rotation 22 of the wheel 20 is coaxial with the longitudinal axis 16 of the cutter bar 4, which in the embodiment of FIG. 2 shows a knife guard 24 to protect against injuries during transport. The gear head 5 is fixed at the lower end 13 of the guide tube 6, the drive shaft 15 being mounted in the guide tube 6 between the drive motor and the gear head 5. In addition to the wheel 20 acting as a spacer, a further spacer is provided on the side of the gear head 5 facing the cutter bar 4, which is also expediently used as a rolling element, for. B. wheel 25 is formed. The axis of rotation 26 of the wheel 25 lies in the longitudinal direction of the guide tube 6 at a distance a from the longitudinal axis 16 of the cutter bar; the wheel 25 also lies at a distance b, measured transversely to the guide tube 6, from the wheel 20 arranged on an axle journal 23 of the gear head 5. The arrangement of the further wheel 25 on the gear head can be provided by means of a flange 27 or the like. The connecting line 28 between the contact surfaces of the spacers designed as wheels 20, 25 lies at an angle 29 to the longitudinal axis 16 of the cutter bar 4. The angle 29 is open to the free end 8 of the cutter bar 4 and is preferably - as also shown in FIG. 6 - on the long side of the cutter bar 4 facing the drive motor.

It may be expedient to arrange the second spacer 25 on the long side of the cutter bar 4 facing away from the drive motor, as is shown in broken lines in FIGS. 2 and 3. In Fig. 4, a bar mower 1 is shown from the user's perspective. The guide tube 6 extends from the plane 30 of the cutter bar 4 at an angle upwards and laterally offset to the free end 8 of the cutter bar. The end 14 of the guide tube 6 facing the drive motor 3 lies approximately in the area between the center of the sserbalkens 4 and its end 8, as indicated by the broken line 31. In the exemplary embodiment according to FIG. 4, the guide tube 6 is provided in the region of the end 14 with a first, fixed handle 11, via which the user controls and guides the bar mower 1, in particular the horizontal position of the cutter bar 4 above the ground. The forces for pushing and pulling the bar mower 1 are primarily introduced in the first handle 10. Furthermore, the operating elements provided for operating the internal combustion engine 3 are arranged in the first handle 10, for example throttle control and throttle control lock. A handle rod 32 is arranged between the first, fixed handle 10 and the cutter bar 4, which is essentially U-shaped and is fixed in the region of a leg 33 on the guide tube 6. For this purpose, a clamp socket 35 is provided, in which the leg is held so as to be non-positively or positively pivotable about an axis 36 lying transversely to the guide tube. In the bar mower 1 designed as a right-hand boom, the handle bar 32 and the handle 11 are essentially on the side of the guide tube 6 facing away from the cutter bar 4, so that the user can, for example, handle the first handle 10 with the right hand and the second handle with the left hand 11 can grasp, which is provided at the free end of the other leg 34 of the handle bar 32. Depending on the working position, the user can move the second, pivotable handle 11 about the pivot axis 36 relative to the guide tube 6 shift, for which only a force is to be applied with which the friction in the clamp 35 can be overcome.

Due to the angle 29 between the connecting line 28 of the contact points of the spacers 20 and 25 designed as wheels and the longitudinal axis 16 of the cutter bar 4, the cutting height h of the cutter bar 4 above the floor 37 is also changed with a simple height shift of the handle 10 on the guide tube 6. When the guide tube 6 is lowered, the cutting height h increases; when the guide tube 6 is raised, the cutting height h becomes lower.

5, the wheel 20 provided as a spacer is arranged between the gear head 5 and the cutter bar 4. The diameter D of the rolling circle 50 of the wheel 20 is of such a size that - viewed in the axial direction - the cutter bar 4 lies largely, preferably completely, within the contour of the rolling circle 50. 5, the axis of rotation of the wheel 20 coincides with the longitudinal axis 16 of the cutter bar 4. The knife bar extends approximately perpendicular to the end face 51 of the wheel 20 away from the gear head 5. On the side of the gear head 5 facing away from the cutter bar 4, a further spacer in the form of a wheel 55 can expediently be arranged, which is held rotatably on an axle pin 23 of the gear head 5.

In the exemplary embodiment according to FIGS. 6 and 7, a roller 21 is provided as the only spacer, which is preferably arranged between one end of the cutter bar 4 and the gear head 5. The gearbox 5 heads on a journal, which simultaneously forms the connection between the gear head 5 and the cutter bar 4. In plan view of the cutter bar 4, its longitudinal axis 16 and the axis of rotation 22 of the roller are congruent; 6, the axis of rotation 22 and the longitudinal axis 16 show a vertical distance from one another. The roller 21 has a wide contact area w, which ensures a sufficiently stable support of the cutter bar 4 which projects freely from the gear head 5. The embodiment according to FIGS. 6 and 7 is particularly expedient for the same cutting height over the operating period, the cutting height being advantageously adjustable, as shown in FIG. 6. The spacer designed as a roller 21 has an inner hub 43 on which the gear head 5 is held in a height-adjustable manner. In this way, the cutter bar 4 can be adjusted in height relative to the roller 21. The roller also has the advantage that a good introduction of force for the feed is possible; the maximum size of the rolling circle 50, which is ensured in such a way that the contour of the cutter bar 4 lies largely, preferably completely, in axial view within the rolling circle 50 of the diameter D, has an advantageous effect. In addition, with the guide roller 21 it is achieved that when cutting out trenches and other terrain profiles the cutting height remains almost the same as shown by the arrows h.

Instead of a single roller with the rolling circle 50 of diameter D, according to the exemplary embodiment according to FIGS. 8 and 9, a plurality of rollers 21 'of smaller diameter d arranged adjacently in the circumferential direction over part of the rolling circle 50 can be provided, which roll over an imaginary rolling circle 50 in the circumferential direction a partial circumference of about 180 ^* are arranged next to each other. The ends of the rollers 21 'are in C-shaped holding plates 60 rotatably mounted, which holding plates 60 are fixed to the housing of the gear head 5. The C-shaped holding plates 60 are designed in the manner of runners on their outer edges 61, two adjacent rollers 21 'each standing on the floor 37 with an imaginary contact surface 37'. In the exemplary embodiment shown, six small rollers 21 'are held between the C-shaped holding plates 60 and are at approximately the same angular distance from one another with respect to the center of the rolling circle 50.

The arrangement of the individual roller-shaped spacers 21 'is provided such that there is the same distance h between the contact surface of a smaller roller 21' and the cutting edge of the cutter bar 4, so that an approximately constant cutting height of the cutter bar 4 is ensured in any working position. The rollers 21 'of smaller diameter d can also be used to guide a rotating treadmill 80 such. B. a link chain, a textile tape or the like. Such a treadmill 80 ensures that there is a relatively large contact area, which enables the bar mower to be guided well.

As the top view in FIG. 9 shows, the spacer 21 composed of individual smaller rollers 21 'with the diameter d, according to the embodiment according to FIG. 6, lies at one end of the cutter bar 4 between the latter and the gear housing 5. The axial view according to FIG. 8 makes it clear that the smaller rollers 21 'lie approximately on a peripheral portion of a common rolling circle 50 which has the diameter D and within which the contour of both the gear head and the cutter bar 4 lies. The embodiment according to FIGS. 10 and 11 corresponds in principle to that according to FIGS. 8 and 9; the spacer 20 is composed of individual wheels 20 ′, which are fixed to a C-like holding plate 60, in a manner similar to an Indian skate shoe. To fix the individual wheels 20 ', a holding plate 60 on one end of the wheels 20' is sufficient; In the exemplary embodiment shown, four wheels 20 ′ are provided, which are arranged adjacent to one another on a circumferential section of an imaginary rolling circle 50. The dimensions are such that the imaginary contact surface 37 ′, determined by two rollers in each case, lies at a predeterminable distance h from the cutting edge of the cutter bar 4. Regardless of the adjacent rollers 20 'which provide the support, the same distance h between the cutting edge of the cutter bar 4 and the floor 37 is ensured in each case.

The angular distances of the wheels 20 ′ measured with respect to the center point of the rolling circle 50 are approximately the same.

As shown in FIG. 11, the spacer 20 composed of individual wheels 20 'can be mounted near the cutter bar 4 at its end facing the gear head 5, at a distance from the end of the cutter bar 4 near the gear head or on the side of the gear head 5 facing away from the cutter bar 4.

Fig. 12 shows a side view of a C-shaped holder for rolling elements such. B. wheels 20 '. The C-shaped holder 60 is designed as a circular section of the rolling circle 50, the circular segment extending over a circumferential angle of approximately 130 ". The contour of the cutter bar 4 and the - not shown - gear head is preferably within the rolling circle 50.

The circular edge 61 of the holding plate 60 facing the floor 37 is flattened approximately in the center and in this area two individual wheels 20 'are mounted which define a contact surface 37' which - perpendicular to the cutter bar 4 - affects the circular edge 61 of the rolling circle 50. The arc sections of the circular edge 61 adjoining the right and left of the contact surface 37 'are skid-like and act together with the individual wheels 20' rotatably mounted on the holding plate 60 as a rolling / sliding spacer 20.

An advantageous embodiment is achieved if, under the longitudinal axis 16 or the axis of rotation 22, a central spacer is rotatably mounted as a wheel 120 on the holding plate 60 - with respect to the rolling circle at a corresponding angular distance - adjacent further wheels 120 'are provided. A total of five wheels are preferably provided, of which wheel 120 forms the middle wheel.

FIG. 13 shows a bar mower 1 in which the end 13 of the guide tube 6 adjoining the gear head 5 is designed as a horizontal connecting section 38, which is approximately parallel, preferably in the plane 30 determined by the cutter bar 4 (FIG. 4) . This configuration enables obstacles such as guardrails, fences or the like to be passed under.

It is also clear from FIG. 13 that the guide tube 6 rises from the connecting section 38 at an angle 39 such that the fixed handle 10 adjacent to the drive motor 3 is at a height 40 which is approximately the stood the user's hand above the floor. This ensures that the bar mower 1 according to the invention can be carried and guided comfortably even over longer operating times.

As shown in FIG. 14, the guide tube 6 can also expediently have a vertical connecting section 41 at its lower end 13, which is approximately vertical on the plane 30 determined by the cutter bar 4.

In a further embodiment, the guide tube 6 runs in a straight line over its entire length and at an angle 42 to the plane 30 determined by the cutter bar 4.

To support the cutter bar 4, a support element 71 is provided on its free end 70 facing away from the gear head 5. The support element 71 is formed from a partially round sheet metal bracket, in particular a spring sheet bracket or the like, which is preferably fixed at one end by means of a fastening screw 72 in the cutting area on the guide bar 17 of the cutter bar 4. The support element 71 preferably extends counter to the feed direction 73 on the long side of the cutter bar 4 facing away from the feed direction.

15a, the lug-like support element 71 is shown as a separate component; 15b shows a support element 71 ', which is designed as a solid skid body and has a central fastening region 74, in which the guide bar 17 of the knife bar 4 comes to rest. The massive runner body extends on both sides of the guide beam 17 and is therefore suitable in the feed direction 73 and counter to the Feed direction 73 of a support function without ensuring the risk of snagging.

In the exemplary embodiment according to FIG. 16, a support wheel 75 is fixed on the guide beam 17 to support the end 70 of the cutter bar 4, said support wheel being pivotable about a vertical axis 76 in the direction of the double arrow 77 so that it is in the feed direction 73 as well as counter to the feed direction 73 can act.

In the exemplary embodiment according to FIG. 17, a further embodiment of a handle rod 32 is shown, which consists of an approximately U-shaped bracket, one leg 32a of which is fixed on the guide tube 6 in the direction of the double arrow 32b. The other leg 32c is - like the first leg 32a - directed towards the ground and thus enables a relaxed grip position for a user who can grip the legs 32a and 32c and in this way can easily and effortlessly guide the bar mower.

In the exemplary embodiments according to FIGS. 1 and 2, the cutter bar 4 is arranged on the left from the user's point of view; 4, the cutter bar is arranged on the right from the user's point of view. It can be expedient to design the cutter bar 4 to be pivotable about the gear head 5 about an axis which is upright with respect to the plane 30 of the cutter bar. In any case, it is advantageous if the cutter bar 4 projects freely from the gear head 5 and in this respect no support elements provided on the cutter bar are obstructive during work. The support elements 20, 21, 25 provided in the area of the gear head 5 are inherently rigid support elements which do not yield even with large forces.

Claims

 Expectations Hand-guided bar mower (1) with a guide tube (6) which has a gear head (5) at one end (13) for driving a cutter bar (4) lying transversely to the guide tube (6) and a drive motor (3) at the other end (14) ) which is drive-connected to the gear head (5) via a shaft (15) mounted in the guide tube (6), and with at least one handle (10, 11) provided on the guide tube (6) for guiding the bar mower (1) and with a spacer (20, 21) rotating about an axis (22) which is approximately parallel to the longitudinal axis (16) of the cutter bar (4) and which also determines the cutting height (h) of the cutter bar (4), characterized in that the spacer (20, 21 ) is arranged in the area of the gear head (5) that the knife bar (4) lies axially to the end face of the spacer (20, 21), and that - seen in the axial direction - the knife holder (4) preferably largely within a maximum rolling circle (50) the spacer (20, 21). Bar mower according to claim 1, characterized in that the spacer (20) is a rolling element such as a wheel (20), a roller (21) or the like, the diameter (D) of which advantageously determines the maximum rolling circle (50). 3. Bar mower according to claim 1, characterized in that the spacer (20) is formed from a plurality of individual elements, in particular rolling elements (20 ', 21') arranged adjacent to one another in the circumferential direction over part of the rolling circle (50). 4. bar mower according to one of claims 1 to 30, characterized in that the gear head (5) is arranged at one end of the cutter bar (4) and in the region of the other end of the cutter bar (4) preferably a support element (71, 71 ', 75) in particular a wheel (75), a runner (71, 71 ') or the like is arranged. 5. bar mower according to one of claims 1 to 4, characterized in that the spacer (21, 25) between the cutter bar (4) and the gear head (5) is arranged. 6. bar mower according to one of claims 1 to 5, characterized in that the bar mower (1) in the region of the gear head (5) has a second spacer (25) which is at a distance (a) to the longitudinal axis (16) of the cutter bar and an imaginary connecting line (28) between the spacers (20, 25) with the longitudinal axis (16) of the cutter bar (4) forms an angle (29) which is preferably open to the free end (8) of the cutter bar (4). 7. bar mower according to one of claims 1 to 6, characterized in that the spacer (20, 21) is adjustable in height, preferably has a hub (43) on which the gear head (5) is mounted adjustable in height. 8. bar mower according to one of claims 1 to 7, characterized in that the cutter bar (4) is equipped on both long sides with cutting blades (18) and preferably has two counter-rotating knives (18) on one long side. 9. bar mower according to one of claims 1 to 8, characterized in that the axis of rotation (22) of the rolling circle (50) in plan view of the cutter bar (4) with its longitudinal axis (16) coincides, preferably coaxially with the longitudinal axis (16) . 10. bar mower according to one of claims 1 to 9, characterized in that the drive motor (3) facing end (14) of the guide tube (6) - seen in the longitudinal direction of the bar mower (1) - in a region between the center and the free End of the cutter bar 4 is.