GB2354421A

GB2354421A - Stepped pruner for trees

Info

Publication number: GB2354421A
Application number: GB9922839A
Authority: GB
Inventors: Jung-Hsien Chang
Original assignee: CHANG JUNG HSIEN
Current assignee: CHANG JUNG HSIEN
Priority date: 1999-09-22
Filing date: 1999-09-27
Publication date: 2001-03-28
Also published as: GB9922839D0; DE29916701U1

Abstract

A tree pruner is composed of a fastening piece 10, cutting piece 30, and two swivel piece 40 and 41. The fastening piece is provided with a connection portion 11 which is in turn provided with a puller 12 and is fastened to a bracing rod 20. The fastening piece is provided at one end thereof with a blade 13. The cuffing piece is fastened pivotally with the fastening piece and provided with a toothed slot 31 and a tool portion 32 capable of cooperating with the blade of the fastening piece. The two swivel pieces are fastened pivotally with the fastening piece and provided with a control element 42 which is put through the toothed slot and is linked with a spring 44. When a cord 46 is pulled, the cutting piece is actuated to execute the severing of a tree twig in conjunction with the blade of the fastening piece.

Description

2354421 PATENTS ACT 1977 Agents' Reference: P13752GB-H/JCC/ac

DESCRIPTION OF INVENTION

Title: "Stepped Tree Pruner" THE PRESENT INVENTION relates generally to a pruner, and more particularly to a stepped tree pruner capable of pruning a tree with ease and speed.

The conventional tree pruner is intended to remove dead or living parts from a tree so as to increase fruit or flower production or improve the tree form. As shown in Figure 1, a tree pruner of the prior art is provided at the top end thereof with a bracing rod I having a fitting body I I which is in turn provided with a fastening piece 12. The fastening piece 12 is provided at one end thereof with an arcuate portion 121 and is fastened pivotally at other end thereof with an arcuate portion 121 and is fastened pivotally at other end thereof with a pull rod 13. Located between the pull rod 13 and the fastening piece 12 is a tension spring 14. The fastening piece 12 is fastened pivotally with a cutting piece 15 which is fastened pivotally at other end thereof with the pull rod 13. The pull rod 13 and the fitting body I I are provided respectively with a pulley 16, 17. A pull cord 18 runs through the pulleys 16, 17. As the pull cord 18 is pulled, the pull rod 13 and the cutting piece 15 are actuated.

In operation, the arcuate portion 121 of the fastening piece 12 and the cutting piece 15 are supported on a tree twig before the pull cord 18 is pulled to actuate the pull rod 13 to swivel so as to actuate the cutting piece 15 such that the tree twig is severed by the cutting piece 15 in conjunction with the arcuate portion 2 121. As the pull cord 18 is let go, the pull rod I') and the cutting piece 15 are forced by the elastic force of the tension spring 14 to return to their original positions. The tree pruner is once again ready to work.

Such a tree pruner of the prior art as described above is defective in design in that the cutting piece 15 and the arcuate portion 121 are not able to sever a rough tree twig in one step, and that the user of the tree pruner must pull zhe pull cord 18 with a greater effort to actuate the cutting piece 15 and the arcuate portion 121. In other words, the tree pruner of the prior art does not work efficiently.

The primary objective of the present invention is to provide an improved tree pruner free from the shortcorning of the prior art tree pruner described above.

In keeping with the principle of the present invention, the foregoing objective of the present invention is attained, in a preferred embodiment of the invention, by a tree pruner consisting of a fastening piece, a cutting piece, and two swivel pieces. The fastening piece is provided at the lower end thereof with a connection portion having a pulley, A bracing rod is fastened with the connection portion. The fastening piece is provided at other end thereof with a blade. The cutting piece is pivotally fastened with the fastening piece and provided at one end thereof with a toothed slot. The cutting piece is ftirther provided with a tool portion capable of cooperating with the blade. The two swivel pieces are fastened pivotally with the fastening piece. A control element is located between the two swivel pieces such that the control element is put through the toothed slot, and that the control element is linked with a spr-,,ng. The two swivel pieces are actuated to swivel by a pull cord such that the cutting piece is actuated -to execute the cuuing of a tree twig in conjunction with the 3 blade. The cutting of the tree twig is carried out in one or more steps with a minimum of effort.

The foregoing objective, features, functions and advantages of the present invention will be more readily understood upon a thoughtful deliberation of the following detailed description of a preferred embodiment of the present invention with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGURE I shows a schematic view of a tree pruner of the prior art;

FIGURE 2 shows a schematic view of a tree pi-uner of the present invention; FIGURE 3 shows an exploded view of the tree pruner of the present invention; FIGURE 4 shows a plan schematic view of the tree pruner of the present invention; FIGURE 5 shows a schematic view of the tree pruner of the present invention in action; FIGURE 6 shows another schematic view of the tree pruner of the present invention in action; FIGURE 7 is a schematic view illustrating the adjusting of the retaining slot of the present invention; 4 FIGURE 8 is another schematic view illustrating the adjusting of the retaining slot of the present invention-, and FIGURE 9 shows a schematic view of the tree pruner of the present invention at work.

As shown in Figures 2 and 3), a tree pruner embodied in the present invention is composed of a fastening piece 10, a cutting piece 30, and two swivel pieces 40 and 4 1, forming a lever.

The fastening piece 10 is provided at the lower end thereof with a connection portion I I having a pulley 12. The connection portion I I is fastened with a bracing rod 20. The fastening piece 10 is further provided at other end thereof with a blade 13. The fastening piece 10 is still further provided with an arresting block 14.

The cutting piece 30 is pivotally fastened with the fastening piece 10. The cutting piece 30 is provided with a toothed slot 3 1 and a tool portion 32 capable of cooperating with the blade I).

The two swivel pieces 40 and 41 are fastened pivotally with the fastening piece 10 such that the two swivel pieces 40 and 4-1 are parallel to each other. Located between the first swivel piece 40 and the fastening piece 10 is a tension spring 43. The swivel pieces 40 and 41 are provided with a slide slot 47 for receiving a control element 42 which is put through the toothed slot 31 of the cutting piece 30. The control eleinent 42 is a bolt, which is put through the first swivel piece 41 to en-age a nut 48 located in the other side of the second swivel piece 40. A spring 44 is located between the first swivel piece 40 and the control element 42. The first swivel piece 40 is provided at the top end thereof with a pulley 45 in which a pull cord 46 runs. The pull cord 46 also runs through the pulley 12 of the connection portion I I of the fastening piece 10.

As shown in Figure 4, before the tree pruner of the present invention is at work to sever a tree twig, the cutting piece 30 is vertically located such that the tool portion 32 and the blade 13 of the fastening piece are provided therebetween with a receiving space for receiving the tree twig. In the meantime, the two swivel pieces 40 and 41 are pulled by the tension spring 43 to swivel upwards, whereas the control element 42 is pulled by the spring 44 to urge the slide slot 47 and to locate at a lower urging point -3)1 A of the toothed slot 3 1 of the cutting piece 30.

As shown in Figure 5, if the tree twig is relatively small in diameter, the cutting operation can be initiated by using the cutting piece 30 and a retaining slot 3 11 of a greater shearing force, in conjunction with the control element 42. The pull cord 46 is pulled to actuate the two swivel pieces 40 and 41 to swivel downwards at the same time to catch the spring 44 located between the first swivel piece 40 and the control element 42. The control element 42 is actuated by the elastic force of the spring 44 to displace upwardly to move from the lower urging point 3 IA of the toothed slot 3 1 of the cutting piece 30 into the retaining slot 311. As the pull cord 46 is continuously pulled downwards, the cutting piece 30 is actuated by the control element 42 to swivel downwards to bring about a shearing force. The tool portion 32 of the cutting piece 30 swivels in reverse to cooperate with the blade I') of the fastening piece 10 so as to sever the tree twig.

As shown in Figure 6, if the tree twig is relatively tough and large in diameter, the cutting operation may be can-led out in two or more steps. Under such a 6 circumstance as described above, the pull cord 46 is pulled to actuate the two swivel pieces 40 and 41 such that the control element 42 is displaced and retained in the retaining slot -3) 11. The pull cord 46 is continuously pulled such that the cutting piece 30 is actuated by the control element 42 to swivel, thereby causing the tool portion 32 of the cutting piece '10 to cooperate with the blade 13 of the fastening piece 10 so as to make a cut into the tree twig without severing the tree twig. Now referring to Figures 7 and 8, the control element 42 is so adjusted to locate in another retaining slot 3 12. That is to say, the cord 46 is released sufficiently to allow the lever formed by pieces 40 and 41, to pivot upwardly, tinder the influence of tension spring 43, sufficiently to move the bolt 42, held captive M the slots in the pieces 40 and 41, up into the next higher slot or notch 3 12 in ratchet formed by toothed slot 3 1. The cord 46) IS again pulled to swing the blade 32 still closer to the blade 13, cutting still further through the twig. If necessary, the cord. 46 can then be released again sufficiently to allow the lever 40, 41 to swing upwardly again and move the bolt or pawl 42 into the next higher notch in the ratchet 3 1, and so on until the twig can be completely cut through. The arresting block 14 prevents the blade 32 from being pivoted further away from the blade 13 than the position shown in Figure 2. In other words, the cutting of a twig using the pruner involves the following steps. In light of the arresting block 14, the swivelling motion of the cutting piece 30 is confined to make the severing of the tree twig relatively easy. The swivel pieces 40 and 41 are allowed to swivel upwards for a small range, thereby causing the control element 42 to move from the retaining slot 3 11 to the lower urging point 3) IA of the toothed slot 3) I of the cutting piece 30. As the pulling force is continuously released, the control element 42 is forced by the pulling force of the spring 44 to inove from the lower urging point 3 IA to the retaining slot -3) 12. Now referring to Figure 4 and 9, the operator of the tree pruner pulls the pulling cord 46 once agam to actuate the swivel pieces 40 and 41 to swivel downwards, thereby causing the control element 42 to actuate ZD 7 the cutting piece 30 to swivel downwards. In light of the cutting piece 30 being confined by the arresting block 14, the cutting range of the cutting piece 30 is so shortened as to result in a reduction in the application force. In the meantime, the tool portion 32 of the cutting piece 30 cooperates with the blade 13 of the fastening piece 10 to execute the final step of the severing action of the tree pruner. As the tree twig is severed, the pull cord 46 is let go such that the swivel pieces 40 and 41 are forced by the elastic force of the tension spring 43 to return to their original positions, and that the cutting piece 30 is forced by the torsion spring 33 to return to its original position. The tree pruner is once again ready for action to sever another tree twig.

The present invention makes the tree pruning an easy chore, thanks to the control element 42 which can be retained in the retaining slots 3 11 and 312 so as to bring about the severing action in a plurality of steps.

The embodiment of the present invention described above is to be deemed in all respects as being merely illustrative and not restrictive. Accordingly, the present invention may be embodied in other specific forms without deviating from the spirit thereof The present invention is therefore to be limited only by the scopes of the following appended claims.

In the present specification "comprise" means "includes or consists of' and to comprising" means "Including or consisting of'.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any

8 combination of such features, be utillsed foi- realising the invention in dive,,,se forms thereof

Claims

9 CLAIMS

1. A tree pruner comprising: a fastening piece provided at one end thereof with a connection portion which is provided with a pulley and fastened with a bracing rod, said fastening piece further provided at other end thereof with a blade; a cutting piece fastened pivotally with said fastening piece and provided with a plurality of toothed slots, said cutting piece further provided with a tool portion capable of cooperating with said blade; and two swivel pieces fastened pivotally with said fastening piece and provided therebetween with a control element which is put through said toothed slots of said cutting piece, one of said two swivel pieces and said fastening piece being provided therebetween with a tension spring which is fastened at both ends thereof with said fastening piece and said one of said two swivel pieces, said control element being linked with a spring, one of said swivel pieces provided with a pulley in which a pull cord runs, said pull cord intended to actuate said swivel pieces to swivel.

2. The tree pruner as defined in claim 1, wherein said swivel pieces are provided with a slide slit for disposing said control element.

3. The tree pruner as defined in claim 1, wherein said swivel pieces and said cutting piece are pulled by a torsion spring.

4. The tree pruner as defined in claim 1, wherein said control element is a bolt which is engaged with a nut via said slide slots of said swivel pieces and said toothed slots of said cutting piece.

5. The tree pruner as defined in clalin 1, wherein said fastening piece is provided an arresting block located under said cutting piece.

6. A pruner comprising a first inember providing a first blade, a second member pivotally connected with said first member and providing a second blade capable of cooperating witli said first blade, a lever pivotally connected with said first member, cooperating ratchet and pawl means on said lever and said second member, whereby by a reciprocating movement of said lever relative to said second member, said second inember can be made to pivot in a plurality of successive steps on said first member, to move said second blade stepwise towards said first blade.

7. A pruner according to clalin 6 wherein said lever is spring biased, relative to said first member, in a direction opposite to that in which it must be moved to move the second blade closer to the fii-st blade.

8. A pruner substantially as liereinbefore described with reference to and as shown in Figures 2 to 9 of the accompanying drawings.