NZ280562A

NZ280562A - Hand shears with removable blades

Info

Publication number: NZ280562A
Application number: NZ28056295A
Authority: NZ
Inventors: Hugh Willem Bullmore; Richard Paul Watson
Original assignee: Richard Paul Watson
Priority date: 1995-11-30
Filing date: 1995-11-30
Publication date: 1997-02-24
Also published as: ZA9610048B

Description

<div class="application article clearfix" id="description"> 280562 Priority Dat«(s): Cyvnploto Specification Filad: ....4k.d.rZ.'.ffyp s, ae«: if?). ,&&.1k&i2i).Q$r. icmion P.O. Jwjrnnl Mo: ffcH& Patents Form No. 5 Patent No:280562 Dated: 30™ NOVEMBER 1995 Patents Act 1953 COMPLETE SPECIFICATION IMPROVED HAND SHEARS I, RICHARD PAUL WATSON, of 54b Johns Road, Rangiora, New Zealand, a New Zealand citizen, hereby declare the invention for which 1 pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement: 1 N.Z. PATTEST OfFCE -4 DEC 1996 " RECeVF.D 280562 The present invention relates to manually operated shears. Hand shears are known and essentially consist of a set of triangular blades connected together by, and integrally formed v.hh, a sheet-metal spring handle which biases the blades to an open position. The construction and arrangement is such that the two opposing blades articulate in a scissors action as the operator applies and releases manual pressure on the blades. A major disadvantage of current hand shear designs is that the blades cannot be removed for maintenance, or replaced if damaged. When sharpening each blade, severe bending stress is placed on the respective blade and handle portion such that the efficiency of the device may be affected by a change in blade angle or failure of the spring. Wool type variances between animals (e.g. sheep, goats, or llamas) or breeds (e.g. Merino and Romney sheep) require specific blade settings. Further, the blade angle is important in the selection of off-shear coat condition of the stock with particular regard to the season and the stock's habitat. The operator may therefore require several pairs of fixed blade hand shears to gain a suitable range of blade settings. External spring mechanisms in fixed blade hand shears are further prone to failure when the tool is incorrectly stored in an open position or suspended by the spring on a hook or nail in a tool box or on a wall. It is an object of the present invention to provide improved hand shears which will go at least some way towards overcoming some or all of the aforementioned difficulties. A further object of the present invention is to provide versatile hand shears of simple construction. 2 280 5 6 2 The present invention provides hand shears comprising: a pair of opposed blades arranged to operate in a scissors action; a handle comprising two handle portions pivoted together at one end by a pivot; the other end of each handle portion having one of the blades removably secured thereto; the blades being biassed towards an 'open' position by a spring secured between the handle portions. Preferably, each blade is removably secured to the corresponding handle portion by screws or clips. Preferably, the angle of inclination of each blade relative to the corresponding handle portion can be altered. Preferably, said spring comprises a coil spring connected between said handle portions, optionally mounted inside the pivoted ends of the handle portions. By way of example only, a preferred embodiment of the present invention is described in detail with reference to the accompanying drawings in which:- Fig. 1 is a plan view of hand shears in accordance with a first embodiment of the present invention; Fig.2 is an end view of part of Fig. 1 in the direction of arrow IV, depicting the securement of one blade to the respective handle portion; Fig. 3 is a plan view of hand shears in accordance with a second embodiment of the present invention and; Fig. 4 is an end view of part of Fig. 3, in the direction of arrow IV, depicting the securement of one blade to the respective handle portion. Referring to Fig. 1 and 2 of the drawings, the hand shears 2 consist of a pivotable handle 3 having mirror image portions 4 and 5 secured together by a pivot 3a, 3 280562 and a pair of removably secured opposing blades 6, 7. The handle 3 is provided with stop lugs 8 to aid registration of the handle portions 4, 5 into the closed position when hand pressure is applied by the operator. Alternatively, or in addition, one handle portion may be fitted with a non-cross-over finger of known type (not shown). A tensioned coil spring (not visible) biasses the handle 3 to the open position. The coil spring is mounted inside the complementary part-circular bosses 3b of the handle 3, around the pivot 3a, and is arranged to bias the blades 6, 7, to the 'open' position of Fig. 1. Each blade 6, 7, is of conventional shape i.e. triangular in plan. The inner ends of the blades 6, 7, rest against a convex outer surface of the respective recessed handle extremities 41, 5'. Each blade 6 or 7 can be angularly articulated relative to the handle 4, 5 by adjusting the pressure applied by one or more of the locking screws 9. The blades 6, 7, can therefore be tilted in two planes whilst remaining secured to the respective handle portion 4, 5. Referring to Fig. 3, in this embodiment the blades 6, 7, and the handle portions 4, 5, are substantially the same as in Figs. 1 and 2, and therefore are referred to by the same reference numerals. However, the handle portions 4, 5, are formed with shaped finger-guards 10, 11, in known manner. As is the first embodiment, the two handle portions 4, 5, are pivotally secured together by a pivot 3a which extends through the complementary part-circular bosses 3b of the handle portions. However, in place of a coil spring in the bosses, the handle portions 4, 5, and the blades 6, 7, are biassed towards the open position of Fig. 3 by a coil spring 12, which is positioned between the handle portions 4 and 5, adjacent the bosses 3b, with one end of the spring 12 secured to the portion 4 and the other end secured to the 280562 portion 5. The spring 12 biasses the blades towards the 'open' position of Fig. 3. The inner ends of the blades 6, 7, rest against the flat outer surfaces of the handle portions 4, 5, and are secured in position by sets of spaced screws 13. The angle of the blades 6, 7, relative to the handle portions 4, 5, cannot be adjusted as the Figs. 1 and 2 embodiment. Instead of the securing screws 13, the blades 6, 7, could be secured to the handle portions 4, 5, by means of securing clips (not shown), providing the clips permit easy removal and replacement of the blades. In use, the blades 6 and/or 7 are angularly articulated (if adjustable) to a preferred setting. The shears 2 are positioned adjacent the animal's skin and hand pressure is applied by the operator to the portions 4 and 5, pressing the blades towards each other against the bias of the spring (arrow A). A section of wool is cut as the operator applies and releases pressure on the handle 3, effecting a scissors action of the opposing blades 6, 7. Out of use, the shears 2 may be maintained in a closed position by strapping the handle portions 4, 5 together or housing the blades 6 and 7 in a dimensioned and protective cover. Alternatively the blades 6, 7 may be stored separately from the handle 3 by releasing the locking screws 9, 13. To replace or sharpen a blade 6 or 7, the locking screws 9, 13, are released, the blade 6 or 7 is removed and the new or sharpened blade 6 or 7 is secured to the respective handle portion 4 or 5. Preferably, the blades 6, 7 are composed of stainless steel with titanium coated 280562 cutting edges, but any hardenable steel may be used. Preferably, the handle 3 is formed from wood or aluminium. 6 </div>

Claims

<div class="application article clearfix printTableText" id="claims"> 280562 WHAT WE CLAIM IS:

1. Hand shears comprising: a pair of opposed blades arranged to operate in a scissors action; a handle comprising two handle portions pivoted together at one end by a pivot; the other end of each handle portion having one of the blades removably secured thereto; the blades being biassed towards an 'open' position by a spring secured between the handle portions.

2. The hand shears as claimed in claim 1 wherein each blade is removably secured to the corresponding handle portion by means of one or more securing screws.

3. The hand shears as claimed in claim 1 wherein each blade is removably secured to the corresponding handle portion by a securing clip.

4. The hand shears as claimed in claim 2 wherein the angle of inclination of each blade relative to the corresponding handle portion can be altered.

5. The hand shears as claimed in claim 4 wherein the part of each handle portion to which the corresponding blade is secured in convex towards the blade and the angle of inclination of each blade relative to that handle portion can be altered by altering the pressure applied to the blade by one or more of said securing screws.

6. The hand shears as claimed in any one of the preceding claims wherein said spring comprises a coil spring housed inside said one end of said handle portions, around said 280562 pivot.

7. The hand shears as claimed in any one of claims 1-5 wherein said spring comprises a coil spring connected between said handle portions.

8. Hand shears substantially as hereinbefore described with reference to and as shown in Figs. 1 and 2 or Figs. 3 and 4 of the accompanying drawings. RICHARD PAUL WATSON. by his authorised agent, P.L. BERRY & ASSOCIATES. per: El hi.Z. O'-v'Cf. ^4 DEC 1996 </div>