WO1995015078A9

WO1995015078A9 - A cutting tool

Info

Publication number: WO1995015078A9
Application number: PCT/GB1994/002643
Authority: WO
Filing date: 1994-12-02
Publication date: 1995-06-29

Abstract

A horticultural cutting tool adapted for cutting an object such as a plant stem comprising at least two arms (110, 120) crossing at a pivot point (130), the pivot point dividing the arms into handle members (140, 150) rearward of the pivot point and operating members (160, 170) forward of the pivot point, at least one of the operating members being provided with or mounting a blade (200); the cutting tool further comprising means for positioning and holding the object to be cut relative the tool.

Description

A CUTTING TOOL

This invention relates to a cutting tool.

In particular, but not exclusively, this invention relates to a tool for cutting articles in a pre-determined manner and/or a horticultural cutting tool.

Known cutting tools include knives and those that utilise the age-old scissor concept of two parallel blades passing closely by each other, the article to be cut being located between them. Variations include secateurs for cutting plants and wire cutters both of which are arranged for maximum leverage so the cutting ability of the tool increased. One problem with these tools is that it is difficult to cut articles such that all objects cut by the tool are cut in a reliably similar manner, or to cut objects in a non- rectilinear fashion.

Several devices designed for cutting plant stems are known, but they all have the disadvantages of being cumbersome and difficult to use and commonly resulting in inefficient cutting or bruising of the stem being cut.

An object of the invention is overcome one or more of the above difficulties or at least to provide the public with a useful choice. Accordingly, in a first embodiment, the present invention broadly consists in horticultural cutting tool adapted for cutting an object such as a plant stem comprising at least two arms crossing at a pivot point, the pivot point dividing the arms into

handle members rearward of the pivot point and operating members forward of the pivot point, at least one of the operating members being provided with or mounting a blade; the cutting tool further comprising means for positioning and holding the object to be cut relative the tool.

Preferably the positioning and holding means is a recess deeper than the width of the object to be cut.

In a second embodiment, the present investion broadly

consists in a horticultural cutting tool adapted for cutting an object such as a plant stem comprising at least two arms crossing at a

pivot point, the pivot point dividing the arms into handle members rearward of the pivot point and operating members forward of the pivot point, at least one of the operating members being provided with or mounting a blade; the cutting tool futher comprising resilient means against which objects to be cut are pressed by the blade during the cutting operation.

Preferably the resilient means is removable. In a third embodiment the present invention broadly consists in a horticultural cutting tool adapted for cutting an object such as a plant stem comprising at least two arms crossing at a pivot point, the pivot point dividing the arms into handle members rearward of the pivot point and operating members forward of the pivot point, at least one of the operating members being provided with or mounting a blade; wherein the cutting tool further comprises gauge means for assessing the appoximate width of objects to be cut.

Preferably the guage is formed integrally with the housing. In a fourth embodiment the present invention broadly consist in a horticultural cutting tool adapted for cutting an object such as a plant stem comprising at least two arms crossing at a pivot point, the pivot point dividing the arms into handle members rearward of the pivot point and operating members forward of the pivot point, at least one of the operating members being provided with or mounting a blade; wherein the cutting tool further

comprises locking means to retain the cutting tool in a pre¬ determined position.

Preferably the locking means comprises a locking member freely pivotable about a pivot point; the locking member, in a locking position, abuting a lip on one of the operating members, preventing the arms of the tool from moving away from each other; and in an unlocked position, pivoting away from the lip to allow the arms to move away from each other. Preferred embodiments of the invention will now be described with reference to the accompanying drawings in which:

Figure 1 is a side view of a first embodiment of a cutting tool of the present invention. Figure 2 is a plan view of the right hand

operating arm of the cutting tool of figure 1.

Figure 3 is an underneath view of the left

5 hand operating arm of the cutting tool of figure 1.

Figure 4 is a side view showing some internal parts in ghost lines of a second embodiment of a cutting tool of the

10 invention.

Figure 5 is a perspective view of the cutting tool of figure 1.

Figure 6 is a front view of the cutting tool of figure 4 with the locking member's

15 unlocked position shown in ghost lines.

Figure 7 is a plan view of a first embodiment of a cutting blade and blade head for use in the cutting tool of figure 1.

20 Figure 8 is an end view of the cutting blade and head of figure 6.

Figure 9 is an end view of the head of figure

6, having a second embodiment of a cutting blade attached. Figure 10 is a schematic view of a positioning

means, blade and objects to be cut.

Figures 1 to 3 illustrate a first embodiment of a

cutting tool 100 of the present invention. The tool has two arms

110, 120, which cross at pivot point 130, to form two handles

140, 150 and two operating arms 160, 170. Mounted on the operating arms 160 is housing 180 which receives a blade head

190 holding a blade 200. The blade head is preferably removable from the housing 170 either by the blade head being slidable mounted in the housing, or by a snap fit due to a resilience in the sides 210 of the housing or by a removable screw or some other means, as would be clear to a person skilled in the art to which

this invention relates.

The arrangement of the arms 110, 120 is such that if the handles 140, 150 are moved towards each other, the operating arms 160, 170 move towards each other.

When the handles 140, 150 are brought towards each other, the second operating arm 170 abuts the blade 1 to provide for effective cutting of any article to be cut. The second

operating arm suitably has a recess 220 for receiving objects to be cut. For more efficient cutting of the article the recess 220 is

suitably provided with a blade receiving recess 230 formed in the recess 220 for receiving the blade and thus allowing the blade to be pressed completely through the article to be cut. The recess 220 may be lined with a resilient material 240 in which the blade receiving recess 230 is formed, such as rubber, plastic or sponge rubber etc.

Thus, in use, an article to be cut may be positioned in the recess 220, and when the handles 140, 150 are brought towards each other, the blade 190 will cut through the article. Preferred blade configurations are discussed below.

The cutting tool is preferably biassed towards an open position and may have latch means for securing the tool 100 in a closed position when not in use.

The cutting tool 100 is also preferably provided with a gauge 250 for assessing the width of objects to be cut. The gauge may be a sliding gauge or may simply be a plurality of recesses 260 of different widths as shown in figure 3. Objects to be cut which fit within one of the recess 260 are most suitable for use with the cutting tool 100. In addition if it is desired for two objects to be of matching width, for example in a grafting procedure when the cutting tool is being used to cut the stems of a scion and rootstock in a matching manner so they may be joined, the widths of the objects (stems) may be quickly ascertained to find objects (stems) of matching width.

A second embodiment of the invention is shown in figures 4-9.

In this embodiment the head 190 is pivotally mounted to the operating arm 160. A suitable pivot or cam arrangement is shown in figure 4, in which the arm 190 has a projection 270 which is received by a recess 280 (see figure 6) in

the head 180. To assist in smooth action of the tool 100, the top of the projection 270 is preferably rounded. For strength the end

of operating arm 170 may be bifurfurcated so that it may receive and support the end of operating arm 160.

This arrangement allows the blade to move in a straight line towards an object to be cut and therefore prevents any shearing and consequent damage to the object (such as bruising) that might be caused, for example if the blade's path of travel subscribed an arc.

It is envisaged that other pivot arrangements would be suitable, however. In the embodiment shown in figures 4-9, the housing 180 is mounted on the operating arm 170. The housing protects the user from the blade when the tool is in an open position. The recess 220 is formed in the housing and the head

190 and blade 200 are slidable mounted in the housing 180. Obviously, the housing must be open on its underside or must at least have an aperture to allow for movement of the projection

270, between an open and a closed position.

In a closed position when the two handles 140, 150 have been moved towards each other as in figure 4, the head 190 and blade 200 are pushed to the limit of their movement towards the recess 220 by the projection 270. When the handles 140, 150 are then moved away from each other, such as under the force of

a spring 290, the projection drags the head and blade away from the recess 220.

This arrangement allows for a narrower recess 220 which will more firmly hold objects to be cut than the recess 220 of the first embodiment. In a grafting application, the recess positions and holds a stem to be cut, substantially preventing the stem from moving about when being cut and therefore significantly minimising the chances of the stem being bruised as

often happens when prior art cutting tools are used. The resilient lining 240 also avoids the concentration of force on discrete points on a not perfectly straight stem which, if no resilient lining were provided, would be pushed against the rigid edge of the recess 220 during the cutting operation and bruised. For safety, the recess 220 is also preferably shaped so that it can only receive suitable objects to be cut, for example stems, and not other objects, such as fingers; and is of a shape corresponding to articles to be cut, such as a semi-circular shape, in cross section.

In the second embodiment, as the blade 200 passes right through the recess 220, only the side of the recess 220 receiving the cutting edge of the blade 200 would be provided with a blade receiving recess 230 and/or resilient lining 240 with

SU3STITUTE SHEET (RULE 26) a recess. A significant advantage in providing recess on the

resilient lining is that the lining can be removed for easy cleaning, especially of the recess. This is useful because, through constant use, the recess can become clogged with residue from the articles being cut, for example with resin from stems.

As shown in the drawings, the housing 180 is angled relative the handles. This provides the advantage of giving the operating arm 160 and handle 150 better leverage on the blade head so that it is easier for a user to cut through objects in the recess 220, particularly tough objects such as stems of plants, and also results in a cleaner cut being made by the blade. The housing may be substantially the same width as the operating arms 160, 170 or may protrude either side of the arms 160, 170 to form a much larger cutting area (see figure 5). This larger head is very desirable as it allows for an elongate and deep recess 220 which

provides for convenient and accurate placement and support of article to be cut. The recess 220 is preferably deeper that the width of the articles to be cut.

As best shown in figure 6, the tool is desirably provided with a locking member 310 pivotable about a point 320.

The locking member in a locked position abuts against a lip or lips 330 on the operating arm 170 and prevents the arms 140 and 150; 160 and 170 from moving away from each other and opening the

tool. The locking member should be such a length that it performs this locking function when the tool is not quite completely closed. In this way a squeezing of the handles 140, 150 will move the lips 330 away from the top of the locking

member and allow the member to be moved out of its locking position (see the ghost lines on figure 6).

For ease of use, the locking member 310 is most suitably free moving about pivot 320 such that when the tool is held with the handles 140, 150 upward, the locking member 310 will fall through force of gravity into position under lips 330. Similarly, when the tool is held with the handles downward and squeezed together to release the locking member, the member will fall out of the locking position under force of gravity.

For both embodiments of the cutting tool of the invention, the blade may be of any suitable configuration depending on the use to which the tool is put. The blade and blade head are suitably removable from the tool so that the blade may be replaced or sharpened when blunt or broken. In the embodiment shown in figures 4-9, the screw or equivalent at the pivot point 130 may be removed so that the arm 120 may be disengaged from the arm 110 (the operating arm 170 of which may partially surround operating member 160) and disengaged from the head 190. Disengagement of arm 120 then allows the head 190 and blade 200 to be removed from a preferably open or openable rear end 350 of the housing 180 (or forward end, but this would be more dangerous as the blade/head unit would exit

blade first).

One particularly useful application of this invention

is in the area of grafting technology. Grafting of plants is done when a stem of a desirable plant (the "scion") is grafted (joined) onto a stem of plant which has strong healthy roots (the "rootstock"). If secured together the stems eventually grow together and the roots feed the desirable stem.

When grafting procedures are being carried out, many thousands of scions and rootstocks may be grafted onto each other at one time. To ensure the success of the grafting process,

the scion and the rootstock should be cut in a similar and matching manner, preferably at least partially on the diagonal, so that a large surface area of the scion stem and the rootstock stem will be in contact. These cuts are often made by use of a knife or secateurs and require a considerable amount of experience and skill to perfect. This is because incorrectly cut scions and rootstocks will not "graft" or grow together properly. Even when an experienced and skilled worker performs the cuts, the failure rate is still high, since the cuts in the scions and rootstocks must be a very good match to ensure good grafting. Even the known grafting tools do not result in a good success rate as they often bruise the stems being cut and thus reduce their ability to graft

onto another stem (or "take"). To assist in preventing the scion slipping down the rootstock it is preferable that the cut made in the stems not be a straight line, a V-shaped or similar two- directional cut being preferred. The cutting of stems in two

different directions is very labour intensive and when done at speed may be dangerous to the person performing the cuts and

often results in non-matching cuts in stems.

The grafting application of the tool therefore inspired the two possible blade arrangements shown one in figures 7 and 8 and the other in figure 9. These are merely examples, however of many suitable blade shapes. Scions and rootstocks cut with the tool of the present invention will therefore have reliably, and reproducibly matching cuts. This will significantly increase the success rate of grafting operations.

The blade arrangement shown in figures 7 and 8 is illustrated in more detail in figure 10. This blade arrangement is unique in that the long "tail" portion 380 of the blade 200 is slightly concave. When the tool is used in conjunction with curved recess 220 and resilient lining 240, elongate objects, preferably stems, received by the recess are fitted in the curve or of the resilient lining 240 or, if they are narrow as indicated by the "7mm" stem in figure 10, are lifted at the start of the cutting operation to be positioned centrally of the curve in the resilient lining 240.

The cut made in a stem by the "tail" 380 of the blade is very important in a grafting situation, because it determines how much of the cut stem will be available for grafting onto another cut stem. If the tail 380 were straight, as indicated by line 390, smaller stems would suffer from a significantly

reduced grafting area as compared with larger stems. This

problem is overcome by making the tail 380 slightly concave and therefore creating a greater grafting area in the smaller stems especially, than would be created by a straight tail (390). The increased length of the cut made in smaller stems by the tail 380 is indicated in Figure 10 as distance a.

The present invention therefore provides a means

for creating cuts in objects, particularly complex cuts safely, reliably, reproducibly, at speed and with minimal damage to objects being cut. The above describes preferred embodiments of the invention, variations and modifications in which may be made without departing from the scope of the invention as claimed in the accompanying claims.

For example, the blade may be cylindrical for cutting holes in objects. In this case the head 190 and the housing

180 may also be cylindrical.

Although a preferred type of locking member is described any conventional locking means would be suitable.

Claims

1. A horticultural cutting tool adapted for cutting an object

such as a plant stem comprising at least two arms crossing at a pivot point, the pivot point dividing the arms into handle members rearward of the pivot point and operating members forward of the pivot point, at least one of the operating members being provided with or mounting a blade; the cutting tool further comprising means for positioning and holding the object to be cut relative the tool.

2. A cutting tool as claimed in claim 1 wherein the

positioning and holding means is a recess deeper than the width of the object to be cut.

3. A cutting tool as claimed in claim 1, wherein the positioning and holding means is provided on the second operating

member.

4. A cutting tool as claimed in claim 1 or claim 2, wherein the direction of movement of the blade is substantially perpendicular to the longitudinal axis of the positioning and

holding means.

5. A horticultural cutting tool adapted for cutting an object such as a plant stem comprising at least two arms crossing at a pivot point, the pivot point dividing the arms into handle members rearward of the pivot point and operating members forward of the pivot point, at least one of the operating members being provided with or mounting a blade; the cutting tool further comprising resilient means against which objects to be cut are pressed by the

blade during the cutting operation.

6. A cutting tool as claimed in claim 5, wherein the resilient means is removable.

7. A cutting tool as claimed in claim 5 or 6, wherein the

resilient means is located in a positioning and holding means for

positioning and holding the object to be cut.

8. A horticultural cutting tool adapted for cutting an object such as a plant stem comprising at least two arms crossing at a pivot point, the pivot point dividing the arms into handle members rearward of the pivot point and operating members forward of the pivot point, at least one of the operating members being provided with or mounting a blade; wherein the cutting tool further comprises gauge means for assessing the appoximate width of objects to be cut.

9. A cutting tool as claimed in claim 8, wherein the gauge means comprises a plurality of recesses of different widths.

10. A cutting tool as claimed in claims 8 or 9, wherein the guage means is formed integrally with the a housing mounted on one of the operating members.

11. A cutting tool adapted for cutting an object comprising at

least two arms crossing at a pivot point, the pivot point dividing the arms into handle members rearward of the pivot point and operating members forward of the pivot point, at least one of the operating members being provided with or mounting a blade; wherein the cutting tool further comprises locking means to retain the cutting tool in a pre-determined position.

12. A cutting tool as claimed in claim 11 , wherein the locking means comprises a locking member freely pivotable about a pivot point; the locking member, in a locking position, abuting a lip on one of the operating members, preventing the arms of the tool from moving away from each other; and in an unlocked position, pivoting away from the lip to allow the arms to move away from each other.

13. A cutting tool as claimed in claim 12, wherein when the handle members are brought together and the tool is inverted, the locking member pivots freely, under force of gravity, to its locking position under the lip, a slight opening of the handle members holding the lock member in place, and wherein when the tool is turned upright the locking member will remain in the locked position by virtue of a biassing member, biassing the arms away from each other and thereby pressing the lip down on the locking member.

14. A cutting tool as claimed in claim 13, wherein when the tool is upright, a slight closing of the handle members lifts the lip slightly away from the locking member and allows the locking member to pivot away from its position under the lip, under the force of gravity.

15. A cutting tool as claimed in any one of claims 1-14,

wherein the blade is held in a blade head which is attached to or mounted on the first operating member.

16. A cutting tool as claimed in claim 15, wherein the blade head is mounted in a housing.

17. A cutting tool as claimed in claim 16, wherein the blade head is removably mounted in the housing.

18. A cutting tool as claimed in claim 16, wherein the blade head is slidable mounted in the housing.

19. A cutting tool as claimed in any one of claims 15-18, wherein the housing is attached to the first operating member.

20. A cutting tool as claimed in any one of claims 16-18, wherein the housing is attached to the second operating member.

21. A cutting tool as claimed in any one of claims 16-20, wherein the housing is at an angle to the longitudinal axis of one of the arms.

22. A cutting tool as claimed in any one of claims 16-21, wherein a plane through the longitudinal axis of the housing forms a non-right angle with the plane through the longitudinal axis of both the arms.

23. A cutting tool as claimed in any one of claims 16-22

wherein a means for positioning and holding the object to be cut is formed in the housing.

24. A cutting tool as claimed in claim 23, wherein the longitudinal axis of the positioning means is substantially perpendicular to the longitudinal axis of the housing.

25. A cutting tool as claimed in any one of claims 16-24, wherein the blade head is pivotally mounted on one operating member and slidably mounted in the housing.

26. A cutting tool as claimed in claim 25, wherein the first operating member is received by a recess in the blade head, so

that movement of the first operating member in one direction pulls to blade head in that direction, and movement of the first operating member in an opposite direction pulls the blade head in that opposite direction.

27. A cutting tool as claimed in claim 26, wherein the first operating member extends through an aperture in the housing before being received by the recess in the blade head.

28. A cutting tool as claimed in any one of claims 1-27, wherein the second operating member is provided with a blade receiving member for receiving the cutting edge of the blade provided on the first operating member.

29. A cutting tool as claimed in claim 28, wherein the blade receiving member is a recess of a shape substantially corresponding to the shape of the cutting edge of the blade.

30. A cutting tool as claimed in any one of claims 28 or 29, wherein the blade receiving member is located in a means for

positioning and holding an object to be cut.

31. A cutting tool as claimed in any one of Claims 28-30, wherein the receiving member is formed in a resilient means against which objects to be cut are pressed by the blade.

32. A cutting tool as claimed in any one of claims 1-31, wherein the objects to be cut are substantially cylindrical.

33. A cutting tool as claimed in any one of claims 1-32, wherein the cutting edge of the blade is rippled.

34. A cutting tool as claimed in any one of claims 1-32, wherein the cutting edge of the blade lies in a single plane.

35. A cutting tool as claimed in any one of claims 1-32, wherein the cutting edge of the blade bends to form an acute angle with itself and the blade cuts the article into two pieces.

36. A cutting tool as claimed in any one of claims 1-32, wherein the cutting edge of the blade makes a cut in the object to be cut which cut is made in two overlapping directions.

37. A cutting tool as claimed in claim 36, wherein the cutting edge of the blade cuts the object into two pieces.

38. A cutting tool as claimed in claim 35, wherein the bend in the blade divides the blade into two lengths of blade the first length being at least 50% shorter than the second length.

39. A cutting tool as claimed in claim 38, wherein the longer length of blade forms an arcuate section, bending toward the shorter length of blade.

40. A cutting tool substantially as herein described with reference to any one of the accompanying drawings.