GB850299A - Improvements in or relating to power operated hedge trimmers - Google Patents

Abstract

850,299. Hedge-cutters. BOMFORD, D. R. Jan. 27, 1959 [Nov. 4, 1957], No. 34290/57. Class 6(2). A hedge-cutter comprises a cutter bar 11 mounted on a beam 10 supported on a universal joint 22 of the construction described in Specification 645,960, which is in turn supported by a frame 12, 14, 15, 18, 19 attached to a tractor. The beam can therefore pivot about both a horizontal axis, which is parallel to the fore and aft direction of the tractor, and about a vertical axis. Adjustment about the former axis is effected from the lift links 24, 25 of the tractor, the beam 10 being connected to the links via a spring 30 and a lever 28 pivoted at 29 on the tractor. Thus by raising the lift links the cutter can be adjusted according to the height of the hedge. Once part of the hedge has been cut, the cutter can be partially supported by the skid 31 resting upon the hedge, the lift links being lowered slightly so that the beam 10 is then floating and any pitching or rolling of the tractor is compensated for by the spring 30 instead of being translated to the cutter. Pivotal movement of the beam 10 about a vertical axis is controlled by a flexible inextensible, but adjustable tether 38 which is normally maintained in a taut condition by a spring 35. In an alternative arrangement, the tether is of fixed length, and the frame members 18 and 19 are pivoted to the frame member 12. The joint 22 may be mounted on a crank which is in turn pivotally supported on the frame 12, and by turning the crank with the aid of a handle, lengthwise movement of the beam 10 is effected to free the cutter from obstruction. The cutter may be driven through a system of belts and pulleys from the power take off of the tractor, or alternatively an electric motor may be mounted in the place of the counterweight 34.