GB2513966A

GB2513966A - Scythe

Info

Publication number: GB2513966A
Application number: GB201403891A
Authority: GB
Inventors: Michael Ian Hubbard
Original assignee: Individual
Current assignee: Individual
Priority date: 2013-04-04
Filing date: 2014-03-05
Publication date: 2014-11-12
Also published as: GB201403891D0; GB201306070D0; GB2512624A

Abstract

A scythe which comprises an elongated blade 7 having forward and rearward ends and sharpened opposed side edges 9, the blade being connected to a handle 1 by a frame which has an open structure minimising resistance to movement of the scythe when swinging it through herbage in a cutting direction. The blade is upwardly curved in the forward and rearward direction so that the forward and rearward ends of the blade are lifted from the ground in use. The upward curve of the forward and rearward ends of the blade helps to reduce any tendency for the blade to be clogged when swung through different types of herbage and assists the user to vary the angle of attack. An arm support may be mounted to the handle by way of adjustable means. The frame may comprise at least two struts 5a, 5b which may have sharpened or tapered edges in the cutting direction of the blade.

Description

SCYTHE

This invention relates to horticultural cutting tools, especially scythes.

Traditional scythes are heavy and have the disadvantage that they cut in one direction only. They are also laborious to use, particularly in heavy and matted herbage.

GB No.789329 describes a tool for cutting herbage having a blade which is sharpened along opposed longitudinal edges, the blade being connected at one end to a handle.

However, the tool is unbalanced and difficult to use.

An object of the invention is to provide an improved scythe which is adapted particularly for cutting matted herbage but may be used to cut a wide variety of vegetation, including bracken, grass, brambles and even hedges.

According to one aspect of the invention there is provided a scythe which comprises an elongated blade having forward and rearward ends and sharpened opposed side edges, the blade being connected to a handle by a frame which has an open structure minimising resistance to movement of the scythe when swinging it through herhage in a cutting direction, the blade being upwardly curved in the forward and rearward direction so that the forward and rearward ends of the blade are lifted from the ground in use. The lifting of the forward and rearward ends of the blade helps to reduce any tendency for the blade to be clogged when swung through different types of herbage and assists the user to vary the angle of attack.

Preferably, the blade when viewed in plan has curved opposite longitudinal edges and is tapered inwardly in a forward andor rearward direction from the middle of the blade. This gives a more efficient slicing action to the tool and adds to the strength of the blade.

The axis of the handle may pass through the blade at a position forward of the middle of the blade.

There is preferably provided a grip which extends outwardly from the handle for grasping by a user's hand. There may also be provided an arm support mounted on the frame for engagement by a user's arm, whereby a user may grasp and swing the scythe without wrist action. The arm support may be connected to the handle by S adjustable means whereby the position of the arm support may be adjusted to suit a particular user and task.

The frame may comprise two or more struts connecting the blade to the handle and the struts may comprise metal strips, which are preferably.sharpcncd along their edges so as to cut tall vegetation when the tool is used in dense vegetation. Provision of an open frame for linking the blade to the handle helps to minimise resistance to movement of the tool as it is swung in use through vegetation in a cutting direction.

Also, by providing a linkage consisting of two or more struts to the handle (whose points of connection to the blade are preferably spaced lengthwise of the blade), balanced support is given to the blade. Preferably the points of connection of the struts to the blade are joined by a sole plate and the latter is fixed to the blade. The struts and the sole plate may be pai-t of triangular frame connected at its upper end to the handle and at its lower arm to the blade. This strengthens the structure and enables thinner and br lightcr material to be used for the manufacture of the frame.

One suitable material for manufacturing the blade is a hardened, carbon steel.

Alternative materials include nickel/chrome steel. A specific example is the steel used for saw blades.

One embodiment of a scythe in accordance with the invention will now be described with reference to the accompanying drawings in which:-Figure 1 is a side elevation of the scythe; Figure 2 is a plan view of the blade; Figure 3 is an enlarged sectional view taken on the section A-A in Figure 1; Figure lb is an enlarged, sectionaL view taken on the section B-B in Figure 1 and shows the cross-sectional shape of the struts; and Figure Ic is an enlarged, sectional view taken on the section c-c:. in Figure 1 and shows the cross section of the handle and the method of attaching the triangular frame to the handle.

Referring to the drawings, the scythe comprises a handle 1 having a tubular shaft 10, a grip 2 extending outwardly from the handle and a curved arm support 3. The shaft is preferably made from a stiff, lightweight material such as an aluminium alloy or a structwal plastics material such as glass-reinforced resin, In the interests of cost and weight reduction the shaft is preferably a hollow tube, Extending from the handle at an angle and height suitable for grasping by a user's hand, the grip 2 may be made from the same kind of material as the handle. At its proximal end 3a, th.e handle I is attached to the arm support 3 for engagement by a user's upper arm. The latter may be fixed rigidly to the handle end or may be adjustable, e.g. by fabricating the part 4 of the shaft as telescopic tube parts so that its length can be adjusted to accord with the length of the user's forearm. One or more locking pins, preferably spring-loaded, can be provided to maintain the part 4 at its selected length. Similarly, the lower part of the shaft 10 may be adjustable in a lengthwise manner using a similar kind of construction to accommodate users of various heights.

In use, the grip 2 is grasped by the user's hand and the tipper arm engaged in the arm support 3 so that the scything motion is controlled by the muscles of the arm rather than the wris which is thereby protected.

Some or all of the shaft 10 together with the grip and arm support may be sheathed with a material, such as rubber or plastic, to protect it from knocks, and to make it easier to hold without slippage.

At its distal end lOa the handle I is fixed to a triangular frame 5. The frame is formed from two struts, Sa and Sb, which are fixed to the distal end of the handle. At their other end the struts are fixed to a sole plate 6 which is releasably attached to a cutting blade 7 by bolts 8 so that the blade can be removed for replacement with a new blade or for sharpening the existing blade. The bolts may be socket button screws. The sole plate 6 may be a separate item from the struts Sa and 5b or form part of an integral member shaped as the triangular frame 5. In the latter embodiment the struts and the sole plate may be formed from the same strip material, e.g. by bending a length of strip steel into the desired triangular frame. As can be seen flom Figure lb the struts 5a and 5b may be sharpened or tapered at their edges 12 in the cutting directions of the blade to Thcilitate the movement of the tool through lierbage.

Referring particularly to Figures 1 and ib, the struts Sa and Sb may be shaped at their upper ends as semi-circular portions which are fitted into the tubular lower ends of the handle 10. These semi-circular portions may be an interference fit in the shaft or fixed into the shaft, e.g. by riveting or bonding. Alternatively, the upper portions of the struts Sa and Sb niay he fixed to a ring which is dimensioned to slide over the end of the shaft to which it may be attached, e.g. by riveting or adhesively bonding.

As seen best in Figure 1 the blade 7 is curved upwardly in a forward and rearward direction when viewed in elevation from the side so that the forward and rearward ends of the blade are lifted from the ground in use, This facilitates positioning of the blade to attack vegetation in the most effective way and enables the angle of attack to be optimised for users of different heights. Also the forward strut 5b makes a smaller angle with the axis of the handle Ithan the rearward strut 5a so that vegetation can be cut more effectively over a wider ship in front of the user.

Referring to Figure 1, the scythe will be pivoted from side to side about the arm support 3. The extended axis 11 of the handle 10 passes through the blade 7 at a point 14 forward of the middle 13 of the blade 7. This means that more of the blade is behind the point 14 than in front of it. Thc reason for this is to reduce or eliminate the torque about the axis 11 caused by the fact that the front part of the blade 7 is Thrther from the arm support 3 than the rear part. Having to counteract torque would otherwise unnecessarily tire the arm of the user.

Figure 2 shows a plan view of the blade 7 which has opposite longitudinal sharpened edges 9. As can be seen in Figure 2 sharpened edges 9 are curved so that middle of the blade is widest. Thus, the bLade, when viewed in plan, has curved opposite longitudinal edges and they are tapered inwardly towards each other in a forward and/or reanvard direction from the middle of the blade. Sharpening of both edges enables the tool to be used by right and left handed people as well as being capable of being used both on the upswing and the downswing. Preferably the blade is made from carbon steel. This gives a light weight blade which can retain a sharp edge. As an example steels of the kind used to make saw blades are suitable. Preferably the edges are sharpened after drilling the blade for connection to the frame.

The blade may be protected when not in use by fitting a shoe enclosing the blade, A tough, flexible, plastics material is suitable for this purpose.

By its lightweight structure, we have found that the scythe may be in the weight range of 1 -2kg.

The sole plate provides a strong support for the blade which minimizes any buckling of the blade in use.

The invention is not restricted to the details of the foregoing examples.

Claims

CLAIMS: 1. A scythe which comprises an elongated blade having forward and rearward ends and sharpened opposed side edges, thc blade being connected to a handle by a frame which has an open structure minimising resistance to movement through herbage, the blade being curved in the forward and rearward direction so that the forward and rearward ends of the blade are lifted from the ground in use.
2. A scythe according to claim I in which the blade when viewed in plan has curved opposite longitudinal edges and is tapered inwardly in a forward andlor rearward direction from the middle of the blade.
3. A scythe according to claim I or 2 in which the axis of the handle passes through the blade at a position forward of the middle of the blade,
4. A scythe according to any of claims 1 to 3 in which a grip extends outwardly from the handle for grasping by a user's hand.
5. A scythe as claimed in any of claim 4 in which an arm support is mounted on the handle for engagement by a user's arm, whereby a user may grasp and swing the scythe without wrist action.
6. A scythe as claimed in claim 5 in which the arm support is connected to the handle by adjustable means whereby the position of the arm support may be adjusted to suit a particular user and task.
7. A scythe as claimed in any of claims 1 to 6 in which the frame comprises at least two struts, each connecting the blade to the handle.
8. A scythe according to claim 7 in which the struts diverge from the handle and are connected to the blade at positions spaced longitudinally of the blade.
9. A scythe according to claims 7 or 8 in which the struts have sharpened or tapered edges in the cutting directions of the blade.
I 0. A scythe according to any of claims 7 to 9 in which the struts are linked by a sole plate which is attached to the blade.
11. A scythe according to claim 10 in which the struts and the sole plate together form a triangular frame when viewed in elevation.

12, A scythe according to any of claims 7 to ii in which the struts are thin in a direction at right angles to the cutting direction, thereby minimising resistance to movement of the scythe when swinging it in the cutting direction