WO2008120213A2

WO2008120213A2 - Double action cutting tool

Info

Publication number: WO2008120213A2
Application number: PCT/IL2008/000454
Authority: WO
Inventors: Mordechai Uzrad
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-04-02
Filing date: 2008-04-01
Publication date: 2008-10-09
Anticipated expiration: 2009-10-02
Also published as: WO2008120213A3

Abstract

A cutting device includes a first lever arm having a cutting blade attached to a distal end of the first lever arm and a second lever arm, having a support element with a supporting surface attached to a distal end of the second lever arm. The lever arms cross one another and are interconnected by a rigid elongated connecting member having two ends. One end is pivotally connected to the first lever arm and the other end is pivotally connected to the second lever arm, allowing relative shear motion between the blade and the support element, and also allowing sawing motion of the blade relative to the support element, when the distal ends of the arms are gripped and pressed against each other.

Description

DOUBLE ACTION CUTTING TOOL

FIELD OF THE INVENTION

The present invention relates to manual cutting tools. More particularly it relates to a manual cutting tool incorporating simultaneous shearing and sawing actions when cutting.

BACKGROUND OF THE INVENTION

A vast variety of manual cutting tools are available and known. Basically such a tool needs to satisfy three basic requirements: it has to be easy to hold or grip, it has to be convenient to operate, and it has to cut effectively. Conventional manual cutting tools usually employ one of the following cutting methods: shearing, clipping or sawing.

US Pat. No. 5,189,794 (Kuo) disclosed a pair of shears with tongs. The shears overlap the tongs, and the tongs are resiliently held apart so that when the shears are operated and the blades draw near, and the tongs retain the object to be cut.

In US Pat. 5,170,559 (Orthyey et al.) rose gripping shears were described, having a cutting blade cooperating with a support. A clamping piece has a clamping plate, which rests against the support in the closed position, and is movable together with the cutting blade. The clamping piece can be retracted by spring action so to enable holding of the cut stem between the cutting plate and the support.

In US Pat. 5,117,557 (Hartley), a cutting device was disclosed which is able of retaining the severed portion of an object between its jaws. The cutting mechanism (shears, clippers, or cutters) which generally comprise a jaw and a blade which close against each other incorporates a second jaw which moves as the blade so as' to retain the severed portion of the object that had been cut In US Pat. No.4,117,592 (Mori et al.), and US Pat. No. 4,099,326 (Mori et al.) a pair of garden shears is disclosed with the shears having laterally disposed branch retaining means for retaining a branch after it was cut to prevent scattering of the cut branches.

hi our previous invention, published as WO 98/09780 (Easycut Ltd.) an adjustable cutting device was disclosed, provided with a first lever arm having an support element attached to one end and a second lever arm pivotally connected to the first arm, a gripping component attached to the second lever arm, a third lever arm pivotally connected to the first and second arm, a blade attached to the third lever arm, and means attached to the third lever arm for adjusting the distance between the support element and the gripping component to the size of the object to be cut.

As manual cutting tools are hand operated their performance depending on the strength of the user. In order to provide more power and to allow convenient grip, multiple joints were added to various cutting tools, and additional leverage was thus achieved. It is the object of the present invention to provide a manual cutting tool that incorporates both shearing and sawing actions in order to facilitate more powerful and efficient cutting. The sawing action adds a second cutting direction, substantially perpendicular to the shearing action. It is evident that in many cases a person using a commonly available cutter would try to incorporate these two actions by twisting the cutter back and forth while applying the shearing action of the cutter. The present invention seeks to provide a tool that incorporates these actions in its cutting mechanism.

Another object of the present invention is to provide a manual cutting tool that has an initial open position which is regained when the force exerted by the user's gripping hand on its lever arms is released.

Yet another object of the present invention is to provide a manual cutting tool that is convenient to hold and grip. BRIEF DESCRIPTION OF THE INVENTION

The present invention introduces an innovative cutting mechanism which comprises:

A first lever arm having a cutting blade attached to the distal end of said first lever arm; a second lever arm, having a support element attached to the distal end of said second lever arm; wherein said lever arms cross one another and are interconnected by a rigid elongated connecting means whose one end is pivotally connected to the first lever arm and its other end is pivotally connected to the second lever arm, allowing relative shear motion between the blade and the support element, and also allowing sawing motion of the blade relative to the support element

BRIEF DESCRIPTION OF THE FIGURES

In order to better understand and appreciate the present invention a detailed description of the invention is provided below, with reference to the attached Figures, in which:

Fig. IA illustrates a frontal view of a manual cutting tool constructed according to a preferred embodiment of the present invention, in its initial cutting position, with an object to be cut, held between the blade and the support element.

Fig. 1 B illustrates a frontal view of a manual cutting tool constructed according to the same preferred embodiment of the present invention, in a more advanced stage of the cutting of an object positioned between the blade and the support element.

Figs. 2A-2J depict the cutting mechanism portion of a manual cutting tool constructed according to the same preferred embodiment of the present invention, and demonstrate the operation of the tool, in various cutting stages.

Fig. 3 depicts a frontal view of the cutting mechanism portion of a manual cutting tool constructed according to the same preferred embodiment of the present invention, and four optional relative arrangements (1-TV) for the blade and support element, shown in a cross section view (A-A¹) of the cutting mechanism. DETAILED DESCRIPTION OF THE INVENTION AND FIGURES

Reference is made to Fig. 1 A, illustrating a frontal view of a manual cutting tool (1) constructed according to a preferred embodiment of the present invention, in its initial cutting position, with an object to be cut, held between the blade and the support element A first lever arm (2) has a cutting blade (3) attached to its distal end (4). The cutting blade (3) itself defines an angle between the imaginary straight line extending from the blade cutting edge (5) and the distal portion of the first lever arm, where that straight line crosses the arm, which angle preferably may vary between approximately 45° to 135°. Optionally the blade can be curved. A second lever arm (7) has a support element (8) attached to its end. The second lever arm is curved along a portion of the lever arm near its distal end. The cutting blade's edge and the support element's supporting surface are preferably parallel, and may come into contact so as to complete a cut, when the tool is in its closed position, so that thorough cutting of the object to be cut can be achieved. Both lever arms cross one another and are interconnected using an elongated plate (9), whose one end is pivotally connected (11) near thatend to the first lever arm, and whose other end is pivotally connected (10) near the other end to the second lever arm. A rod can optionally be used instead of the plate. When assembled as described above, the lever arms bend toward each other somewhere beyond the gripping area and then cross one another, with the distal ends pointing away from each other. Optionally the proximal ends of the lever arms should not be linearly distanced more than 15 cm apart when the device is in its open position, and not less than 3 cm, when the device is in its close position, in order to allow efficient and effective grip by the user, hi an embodiment designed for single hand operation. Of course, other embodiments for two handed use, or machine use are possible, and larger dimensions would be used.

A recess (6) in the first lever arm designed to accommodate the end of the elongated plate end where it is pivotally connected to the second lever arm, to enhance the user's leverage (and reduce the opposite leverage of the support element) when gripped and operated.

A spring element (12), attached to the support element (8) and the first lever arm 2) (at the distal end of which the cutting blade is attached to) is employed to withdraw the support element away from the cutting blade, when the gripping force applied by the user is released. This is important to facilitate operating of the manual cutting tool of the present invention in a series of repeated actions - in a ratchet-like manner - as will be explained hereafter. Optionally a spring element may be positioned between the lever arms below the crossing point of these arms, for the purpose of forcing them apart, to regain the open position when the user releases the applied force.

The object to be cut is placed between the cutting blade's edge and the support element. When operated, the distal ends of said arms are drawn closer by the force exerted by the person handling the cutter, gripping the proximal ends of said arms, or drawn further apart by the spring element (12).

Fig. 1 B illustrates a frontal view of a manual cutting tool constructed according to the same preferred embodiment of the present invention, in a more advanced stage of the cutting of an object (13) positioned between the blade (3) and the support element (8).

Reference is made to Fig. 2A. The object (13) to be cut (here a stem is shown) is placed between the cutting blade's edge (5) and the support element's supporting surface (14). The supporting surface may optionally be rough in order to increase the friction and prevent sliding of the object on the surface when pressure is applied by the cutting blade. The support element supporting surface also may optionally have a niche (31) into which the object to be cut is inserted at the start of the cutting operation, in order t9 hold the object in place, while the cutting blade initially cuts through it (Fig. 28). At that stage further pressure on the lever arms may result in the severing of the object to be cut, if the cut object is sufficiently thin, but the user applying the force has to struggle against the resistance of the object to the blade forcing its way in shear motion. In that case the tool of the present invention acts no different than any other prior-art common cutter. However, in order to fully utilize the unique features of the manual cutting tool of the present invention, deploying the ratchet-like action of the tool, the user may also release the pressure on the lever arms (Fig. 2C), allowing the support element (8) to be withdrawn back by the spring element (12). When the user resumes applying force on the lever arms, the object to be cut is supported by the support element at a position slightly further along its supporting surface (Fig. 20), and the simultaneous sawing and shearing actions are repeated, causing the blade to further penetrate the object to be cut (Fig. 2E). The sawing action stops when the end of the elongated plate pivotally attached to the second lever arm (10) comes to rest inside the recess (6), preventing any further sawing motion, and enhancing the leverage of the shearing motion (Fig. 2F).

In order to complete the cut it may be necessary to ease the grip on the lever arms, retract the support element and the blade (Fig. 2G), and resume applying force, with the object to be cut now positioned yet further on the support element (Fig. 2H).

Finally the object is severed as the blade and the support element come to a halt (Fig. 21). The severed object is discarded, and when the pressure on the lever arms is released the spring element (12) retracts the support element towards the first lever arm, thus resuming the open position Fig.2 J).

It should be mentioned that although the preferred embodiment depicted in the Figures attached is primarily designed to be used manually, gripped in the palm of the user, it can also be powered, for example electrically, pneumatically or hydraulically. In the case of powered (non-manual) operation, some modifications maybe needed to adjust the device to its purpose, generally providing suitable connecting means for adapting the device to an electrical, pneumatic, hydraulic or other powered systems.

Fig. 3 depicts a frontal view of the cutting mechanism portion of a manual cutting tool constructed according to the same preferred embodiment of the present invention, and four optional relative blade and support element arrangements, shown in a cross section view (A-A¹) of the cutting mechanism, hi arrangement I, the blade (3) is positioned opposite the support element (8) supporting surface (an anvil), and when drawn together the blade comes to rest on the support element supporting surface itself. In arrangement 11, the blade (3) is positioned off the side of the support element (8), and when drawn towards the support element (8) it bypasses adjacent the support element side wall, hi arrangement 111, the support element supporting surface has a groove (32) into which the blade may be inserted, when the manual cutting tool is drawn to its closed position, hi arrangement IV, the support element (8) is made of two parallel plates, kept at a distance from each other, allowing the blade to pass between them at the final stage of the cut

It should be clear that the description of the embodiments and attached Figures set forth in this specification serves only for a better understanding of the invention, without limiting its scope as covered by the following Claims.

It should also be clear that a person in the art, after reading the present specification could make adjustments or amendments to the attached Figures and above described embodiments that would still be covered by the following Claims.

Claims

1. A cutting device comprising a first lever arm having a cutting blade attached to a distal end of said first lever arm; a second lever arm, having a support element with a supporting surface attached to a distal end of said second lever arm; wherein said lever arms cross one another and are interconnected by a rigid elongated connecting member having two ends whose one end is pivotally connected to the first lever arm and whose other end is pivotally connected to the second lever arm, allowing relative shear motion between the blade and the support element, and also allowing sawing motion of the blade relative to the support element, when the distal ends of the arms are gripped and pressed against each other.

2. The device according to Claim 1, wherein an angle no less than 45° is defined between an imaginary straight line extending from an edge of the cutting blade and a distal portion of the first lever arm.

3. The device according to Claim 2, wherein the angle is in a range between 45 to 135 degrees.

4. The device according to Claim 1, wherein said lever arms are each curved along a distal portion of the lever arm.

5. The device according to Claim 1, wherein said cutting blade and the supporting surface of the support element are substantially parallel, and come into contact so as to complete a cut, when said device is in a closed position.

6. The device according to Claim 1, wherein said rigid connecting member comprises a plate.

7. The device according to Claim 1, wherein said rigid connecting member comprises a rod.

8. The device according to Claim 1, wherein a linear distance between proximal ends of the lever arms when the device is in an open position is not more than 15 cm.

9. The device according to Claim 8, wherein the linear distance is not less than 3 cm.

10. The device according to Claim 1 , wherein a recess in the first lever arm is provided designed to accommodate an end of the rigid connecting member and wherein the rigid connecting member is pivotally connected to the second lever arm.

11. The device according to Claim 1, wherein a spring element is provided connecting the support element and the first lever arm to allow withdraw of the support element away from the cutting blade, when a gripping force applied by a user is released.

12. The device according to Claim 1 , wherein a spring element is positioned between the lever arms below a crossing point of the first and second lever arms, forcing them apart, to regain an open position when a user releases the applied force.

13. The device according to Claim 1 , wherein said supporting surface is rough.

14. The device according to Claim 1, wherein said support element has a niche into which an object to be cut is inserted at the start of a cutting operation, in order to hold the object in place, while the cutting blade initially cuts through it.

15. The device according to Claim 1 , wherein the supporting surface has a groove into which the blade may be inserted, when said device is brought to a closed position.

16. A method for cutting comprising:

providing a cutting device comprising a first lever arm having a cutting blade attached to a distal end of said first lever arm; a second lever arm, having a support element with a supporting surface attached to a distal end of said second lever arm; wherein said lever arms cross one another and are interconnected by a rigid elongated connecting member having two ends whose one end is pivotally connected to the first lever arm and whose other end is pivotally connected to the second lever arm, allowing relative shear motion between the blade and the support element, and also allowing sawing motion of the blade relative to the support element, when the distal ends of the arms are gripped and pressed against each other,

placing an object to be cut between the cutting blade and the supporting surface;

pressing the lever arms together repeatedly.

17. The method according to Claim 16, wherein said pressing of the lever arms together is carried out manually.

18. The method according to Claim 16, wherein said pressing of the lever arms together is carried out electrically.

19. The method according to Claim 16, wherein said pressing of the lever arms together is carried out pneumatically.

20. The method according to Claim 15, wherein said pressing of the lever arms together is carried out hydraulically.

21. The method according to Claim 15, comprising positioning the blade off a side of the support element, and pressing the lever arms together thus bringing the blade towards the support element, wherein the blade bypasses adjacent a side wall of the support element.