GB1584149A

GB1584149A - Hedge cutter

Info

Publication number: GB1584149A
Application number: GB3757176A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1977-09-07
Filing date: 1977-09-07
Publication date: 1981-02-04

Description

(54) HEDGE CUTTER (71) I, WILLIAM SAMUEL KINSEY LEE, a British subject, residing at Brownhills, Leebotwood, Church Stretton, Salop, England, do hereby declare the invention for which I pray that a patent may be granted to me and the method by which it is to be performed tu be particularly described in and by the following statement:- This invention relates to machines of the kind which are mounted on and driven by an agricultural or other tractor, for use primarily in cutting back and trimming hedges but which are often also used for such work as scrub clearing and trimming banks, ditches and verges for which purposes some machines have interchangeable special purpose cutting heads, and the term "hedge cutter" is used hereinafter to include all machines of this kind.

The object of the invention is to provide a hedge cutter which is particularly adaptable and convenient in use.

According to the invention there is provided a hedge cutter of the kind described having mounting means adapted to mount the cutter at one end of a tractor in an operative relationship in which one end of a support structure of said means faces towards that end of the tractor; a boom having a proximal section pivoted on the support structure for angular movement about a first axis coincident with or substantially parallel to the longitudinal axis of the tractor in use in a substantially vertical first plane and a distal section pivotally mounted on the proximal section remote from the mounting means for angular movement relative to the proximal section about a second axis parallel to the first axis and in a second substantially vertical plane parallel to the first plane and on that side of the latter plane which is remote from said one end of said structure; and a power driven cutting head mounted on the distal section remote from the second axis, said head being movable with said distal section in a path which does not intersect the path of movement of the proximal section whereby the sections may be swung past each other to carry the head from side to side ob the tractor in use.

The invention further resides in the combination of a hedge cutter as defined in the last preceding paragraph mounted at the front end of and powered by a tractor.

A preferred embodiment of the invention is now more particularly described with reference to the accompanying drawings wherein: Figure 1 is a diagrammatic side elevation of a front mounted hedge cutter; Figure 2 is a front elevation thereof showing various boom positions, and Figure 3 is a side elevation of a modified tractor/hedge cutter combination.

The cutter comprises mounting means in the form ob a support framework 10 dismountably carried on a 3-point linkage 11 at the front of a tractor 12. Framework 10 mounts an articulated boom comprising a proximal section 13 and a shorter distal section 14. Section 13 is pivoted at its lower end for angular movement in a vertical transverse plane about a central longitudinal first axis of the tractor.

The outer end of section 13 has a forwardly projecting journal formation 16 (Figure 1) to receive a hingle-pin on which section 14 is pivotally mounted for angular movement relative to section 13 about a second axis parallel to the first axis. Section 14 moves angularly in a plane in front of section 13 so that it can be swung from side-to-side past the front face of section 13. The free end of section 14 mounts a cutting head 18 which can itself be turned to various angular positions relative to the boom and which is carried in front of section 14, i.e. so that it forms the foremost part of the assembly.

Various types of cutter head may be employed, conveniently provision is made for 'them to be interchanged, for example a flail drum type of head may be employed for trimming hedges, banks etc., and a revolving disc type of cutter head may be substituted for dealing with heavier growths e.g. when cutting back overgrown hedges.

The cutter head is powered from a front P.T.O. shaft 17 (Figure 1) of tractor 12 by way of vee-belts 19s,b,c and pulleys 20a, b, c, pulleys 20a and c being centered on the first and second axes respectively so that belt tension is unaffected by articulation of the boom.

Alternatively the cutter head can be driven hydraulically, a pump driven by the tractor providing pressurised fluid conveyed through a flexible hose along the boom to operate a hydraulic motor of the cutting head.

The sections of the boom are moved to the selected angular positions by hydraulic rams, a first ram 21 (Figure 2) is directly connected between sections 13 and 14 for relative angular movement thereof, while a second ram 22 acts indireotly between framework 10 and section 13 for angular move- ment of the latter. An intermediate lever 23 has its lower end pivoted on framework 10 in front of and below the lower end of section 13, its upper end being provided with a longitudinal slot which is engaged by a forwardly projecting pin on section 13, and ram 22 acts at an intermediate position along the lever.

In this way a greater range of angular move; ment of the boom is provided without the risk of the actuating ram locking at a dead centre position.

The effective length (i.e. the distance from the second axis to the mounting of head 18) of distal section 14 is approximately 9 that of proximal section 13 (i.e. the distance between the first and second axes) so that the free end of the former section swings clear of intermediate lever 23 and support framework 10 when moved from side-to-side of the tractor across its front.

In order to improve the weight distribution of the hedge cutter and tractor combination and in particular reduce the load on the tractor front wheels the modification shown in Figure 3 may be adopted. A counterbalancing lever 30 extends longitudinally beneath the tractor and is pivoted to the tractor at 31 about midway between the front and rear wheels. A counterweight assembly 33 is carried at one end of lever 30 to the rear of the tractor and the other end acts below framework 10 to take at least some of the weight off linkage 11 and the front wheels.

Where the cutting head 18 is hydraulically powered the drive pumps and hydraulic reservoir may conveniently be mounted on lever 30 as part of counterweight assembly 33. Even if lever 30 is not employed it is preferred that said hydraulic pumps and reservoir be mounted at the rear of the tractor to improve weight distribution.

While the invention might be applied to rear mounted cutters the front mounting arrangement is believed to be particularly advantageous as the cutting head 18 is the leading part of the assembly and there are no static parts forward of this to obstruct the cutting action. The head is in full view the operator but is well spaced from him for added safety, and the positioning of the head can be extremely closely controlled by steering the tractor. Moreover the head can cut right into corners and other positions difficult of access. It can be swung to operate on either side of the tractor and the two section boom enables the far side of the hedge or bank to be reached, thus the two sides of a hedge may be trimmed by travelling in the two directions without an idle journey. The articulated boom at the front of the tractor enables the cutting head to be brought right in line with the side of the tractor so that cutting can be effected even in very confined spaces, for example narrow high-banked lanes.

The fact that the cutter head can be swung from side-to-side without having to pass right above the tractor on a fully extended boom gives added stability and avoids possible damage to trees or other overhead structures, or danger from overhead power lines etc.

Moreover there is no excess width when the boom is folded with the cutting head directly in front of the tractor for transport purposes.

WHAT I CLAIM IS: 1. A hedge cutter of the kind described having mounting means adapted to mount the cutter at one end d a tractor in an operative relationship in which one end of a support structure of said means faces towards that end of the tractor; a boom having a proximal section pivoted on the support structure for angular movement about a first axis coincident with or substantially parallel to the longitudinal axis of the tractor in use in a substantially vertical first plane and a distal section pivotally mounted on the proximal section remote from the mounting means for angular movement relative to the proximal section about a second axis parallel to the first axis and in a second substantially vertical pllane parallel to the first plane and on that side of the latter plane which is remote from said one end of said structure; and a power driven cutting head mounted on the distal section remote from the second axis, said head being movable with said distal section in a path which does not intersect the path of move; ment of the proximal section whereby the sections may be swung past each other to carry the head from side to side of the tractor in use.

2. A cutter according to Claim 1 wherein the distal section has an effective length substantially less than that of the proximal section.

3. A cutter according to Claim 2 wherein the effective length of the distal section is from one quarter to three quarters that of the proximal section.

4. A cutter according to Claim 1, 2 or 3 wherein the mounting of the head on said

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. The cutter head is powered from a front P.T.O. shaft 17 (Figure 1) of tractor 12 by way of vee-belts 19s,b,c and pulleys 20a, b, c, pulleys 20a and c being centered on the first and second axes respectively so that belt tension is unaffected by articulation of the boom. Alternatively the cutter head can be driven hydraulically, a pump driven by the tractor providing pressurised fluid conveyed through a flexible hose along the boom to operate a hydraulic motor of the cutting head. The sections of the boom are moved to the selected angular positions by hydraulic rams, a first ram 21 (Figure 2) is directly connected between sections 13 and 14 for relative angular movement thereof, while a second ram 22 acts indireotly between framework 10 and section 13 for angular move- ment of the latter. An intermediate lever 23 has its lower end pivoted on framework 10 in front of and below the lower end of section 13, its upper end being provided with a longitudinal slot which is engaged by a forwardly projecting pin on section 13, and ram 22 acts at an intermediate position along the lever. In this way a greater range of angular move; ment of the boom is provided without the risk of the actuating ram locking at a dead centre position. The effective length (i.e. the distance from the second axis to the mounting of head 18) of distal section 14 is approximately 9 that of proximal section 13 (i.e. the distance between the first and second axes) so that the free end of the former section swings clear of intermediate lever 23 and support framework 10 when moved from side-to-side of the tractor across its front. In order to improve the weight distribution of the hedge cutter and tractor combination and in particular reduce the load on the tractor front wheels the modification shown in Figure 3 may be adopted. A counterbalancing lever 30 extends longitudinally beneath the tractor and is pivoted to the tractor at 31 about midway between the front and rear wheels. A counterweight assembly 33 is carried at one end of lever 30 to the rear of the tractor and the other end acts below framework 10 to take at least some of the weight off linkage 11 and the front wheels. Where the cutting head 18 is hydraulically powered the drive pumps and hydraulic reservoir may conveniently be mounted on lever 30 as part of counterweight assembly 33. Even if lever 30 is not employed it is preferred that said hydraulic pumps and reservoir be mounted at the rear of the tractor to improve weight distribution. While the invention might be applied to rear mounted cutters the front mounting arrangement is believed to be particularly advantageous as the cutting head 18 is the leading part of the assembly and there are no static parts forward of this to obstruct the cutting action. The head is in full view the operator but is well spaced from him for added safety, and the positioning of the head can be extremely closely controlled by steering the tractor. Moreover the head can cut right into corners and other positions difficult of access. It can be swung to operate on either side of the tractor and the two section boom enables the far side of the hedge or bank to be reached, thus the two sides of a hedge may be trimmed by travelling in the two directions without an idle journey. The articulated boom at the front of the tractor enables the cutting head to be brought right in line with the side of the tractor so that cutting can be effected even in very confined spaces, for example narrow high-banked lanes. The fact that the cutter head can be swung from side-to-side without having to pass right above the tractor on a fully extended boom gives added stability and avoids possible damage to trees or other overhead structures, or danger from overhead power lines etc. Moreover there is no excess width when the boom is folded with the cutting head directly in front of the tractor for transport purposes. WHAT I CLAIM IS:

1. A hedge cutter of the kind described having mounting means adapted to mount the cutter at one end d a tractor in an operative relationship in which one end of a support structure of said means faces towards that end of the tractor; a boom having a proximal section pivoted on the support structure for angular movement about a first axis coincident with or substantially parallel to the longitudinal axis of the tractor in use in a substantially vertical first plane and a distal section pivotally mounted on the proximal section remote from the mounting means for angular movement relative to the proximal section about a second axis parallel to the first axis and in a second substantially vertical pllane parallel to the first plane and on that side of the latter plane which is remote from said one end of said structure; and a power driven cutting head mounted on the distal section remote from the second axis, said head being movable with said distal section in a path which does not intersect the path of move; ment of the proximal section whereby the sections may be swung past each other to carry the head from side to side of the tractor in use.

distal section permits selective angular movement of the cutting head relative to the boom sections.

5. A cutter according to any one of the preceding claims including head mounting means which facilitates interchange of one type of cutting head for another.

6. A cutter according to any one of the preceding claims including transmission means for transmitting power from the tractor to the cutting head.

7. A cutter according to Claim 6 wherein the transmission means is a belt drive connectable to a power-take-off shaft of the tractor and including pulleys centered on the axes of movement od the boom sections.

8. A cutter according to Claim 6 wherein the transmission means includes a duct for conveying pressurised hydraulic fluid from a pump powered by the tractor in use to a hydraulic motor for driving the cutting head.

9. A cutter according to any one of the preceding claims including hydraulic rams for selective angular movement of the boom sections.

10. A cutter according to Claim 9 wherein the proximal section of the boom is moved angularly relative to the mounting means by a hydraulic ram acting between the latter and an intermediate lever pivoted on the mounting means remote from the first axis and having a sliding connection with the proximal section so that movement of the ram is multiplied to give a greater range of angular movement of the boom.

11. A hedge cutter substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

12. The combination od a hedge cutter according to any one of Claims 1 to 10 with a tractor, the mounting means being located on the front of the tractor so that the distal section of the boom is swung past the front of the proximal section, and the cutting head is operatively foremost.

13. The combination of Claim 12 wherein the mounting means is attached to a three point linkage at the front of the tractor and the cutting head is driven from a power take off shaft at said front.

14. The combination of Claim 12 or 13 including a counterbalancing lever pivotally mounted beneath the tractor rearwardly of its front wheel axis and extending longitudinally, its rear end mounting a counterweight at the back of the tractor and its front end acting upwardly on the mounting means to transfer at least a proportion of the weight of the mounted cutter away from the front wheels.

15. The combination of Claim 14 wherein said counterweight includes a hydraulic reservoir and pump for operating rams connected to the boom sections and/or a hydraulic motor of the cutting head.

16. The combination of a tractor and a hedge cutter substantially as hereinbefore described with reference to and as shown in the accompanying drawings.