NZ549477A - A jigsaw - Google Patents

Abstract

A power-operated jigsaw is disclosed. The power-operated jigsaw has a removable cartridge for storing a plurality of blades, and blade feed means for removing a blade from the cartridge and feeding it to a driving mechanism of the saw, permitting the blade to be coupled to the driving mechanism in an operative position for use of the saw. The blade is removable from the driving mechanism for storage in the cartridge for re-use,

Description

S"W77 NEW ZEALAND PATENTS ACT 1953 COMPLETE SPECIFICATION After Provisional 2005904671 filed in Australia on 26 August 2005 Davies Collison Cave Reference: 12825830 APPLICANT(S) Arlec Australia Limited Maroondah Highway, Mooroolbark, Victoria 3138, Australia - an Australian company My/Our contact address is: DAVIES COLLISON CAVE 1 Nicholson Street G.P.O. Box 4387QQ Melbourne 3000 Victoria, AUSTRALIA Telephone: 61 3 9254 2777 Facsimile 61 3 9254 2770 Email: mail@,davies.com.au My/Our address for service is: DAVIES COLLISON CAVE c/- James & Wells Level 9, James & Wells Tower 56 Cawley Street Private Bag 11907 DX CP 34005 Ellerslie Auckland NEW ZEALAND INVENTION TITLE: A jigsaw We/I, Arlec Australia Limited hereby declare the invention for which we pray that a patent be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement: 2 9 AUG 2006 I -Received! P:\REC\NZ\Docs\l282S830 240.doc - 28/8/06 P \0PER\RSH\I282583()-CAP doc-28/08/06 -la- A JIGSAW The present invention relates to a power-operated jigsaw.

Among the wide range of powered hand tools available today a jigsaw is particularly useful for cutting shapes and making cut-outs in sheets, and can be adapted for use on a wide range of materials. The cutting action is achieved by imparting a reciprocating motion to a sharpened serrated blade. This is commonly achieved by transferring the rotational motion of the electric drive motor to the blade through a bell crank or some 10 similar assembly. It is fundamental to this type of arrangement that the blade always protrudes beyond the foot plate of the saw so that when in use, the blade is never withdrawn from the work piece. There is an inherent danger of personal injury posed by having a sharp metal blade exposed in this way. It is also an inconvenience that a jigsaw cannot be at rest with the blade directed harmlessly at the surface on which it is placed, 15 because the blade is protruding in that direction. The general shape of this type of saw dictates that it can only rest in equilibrium when placed on one of its two sides. When in this position the blade will be horizontal to the surface it rests on, potentially pointing towards any person nearby.

A much greater threat is posed from inadvertent or accidental operation of a saw which is not actually in use, yet has its blade exposed while it is still engaged to the driving mechanism. If the saw is energised while it is in the rest position on its side, then the exposed blade can cause a major injury. The design of conventional jigsaws necessitates engagement of the saw blade to the driving mechanism when the tool is not in use; although it is possible to remove the blade for replacement when worn, or to exchange for a different type of blade, it is a significant inconvenience to remove the blade after every use for the purpose of storage. 2 9 AUG 2006 I BMcejved P:\OPER\RSH\l 2825830-C AP.doc-28/08/06 Fig 1 shows a conventional jigsaw with a blade 2 protruding through a foot plate 4. The distance the blade protrudes is a function of the total length of the blade, and the point of the reciprocating cycle that was reached at the time the machine ceased to operate. In general terms this could be in the range 50 - 70% of the total length of the blade. If the 5 total length of the blade is 90mm for example, then there could be more than 60mm in view. This not only presents a danger in respect of having a sharp, and perhaps hot, immediately after use, metal blade exposed, but also imposes a restriction on the ability to store the saw conveniently, without the blade 2 exposed. It is not possible to stand the saw in a way which renders the blade harmless without providing it with a custom-made stand, 10 because this would require the blade to be oriented vertically down, with the foot plate 4 horizontal. A custom-made stand is capable of providing the required function, but only to a limited degree. It is the nature of a jigsaw and other similar powered hand tools that they are portable and thus suitable for use in many and varied locations and conditions. If an operator relies on a stand to provide protection, then the stand must be adapted to the 15 conditions of use. For example, in a workshop a stand can be effective if placed on a bench adjacent to the work, but in a confined space such as a ceiling, on the sloping surface of a roof, or up a ladder, then a stand must be adapted to these prevailing conditions. It will be very difficult to devise a stand which might be effective in all possible circumstances.

According to the present invention there is provided a power-operated jigsaw having a removable cartridge for storing a plurality of blades, and blade feed means for removing a blade from the cartridge and feeding it to a driving mechanism of the saw to permit the blade to be coupled to the driving mechanism in an operative position for use of the saw, the blade being removable from the driving mechanism for storage in the cartridge for re-25 use.

Accordingly, the saw can be put into a "safe mode" when not in use with the blade removed from the saw and stored within the cartridge for further use. in/ellectual property office of n.z. 29 AUG 2006 r> r-^ m.

P:\OPER\RSH\l2825830-CAP.doc-28/08/06 -3 Advantageously, in one form the blade feed means is also actuable to return the blade from the operative position into the cartridge for storage when the saw is not in use. Preferably the feed means is also selectively operable to remove a used blade from the operative position and to discard that blade to permit its replacement by a further blade from the cartridge.

In an alternative form, the blade feed means does not return the blade from the operative position to the cartridge for storage, but instead discharges the blade from the saw to permit its manual insertion into the cartridge for storage purposes.

Advantageously, the feed means includes a gripper device for releasably holding the blade for movement between the cartridge and the operative position. Preferably the feed means is a simple mechanical system which is manually operated by a slider or other control on the body of the saw. The slider or other manually-operated control is associated with a 15 manually-released safety catch to prevent accidental or inadvertent actuation of the feed means. The safety catch can be linked to the drive system of the saw, for example to the trigger by which the saw is operated, to ensure that the feed means will not function when the saw is in use.

Securement of the blade into, and its subsequent release from, the driving mechanism of the saw occurs automatically by operation of the feed means without the application of a special tool for that purpose.

Advantageously the cartridge is releasably attached to the body of the saw by quick-release 25 fastenings.

The present invention also provides a replaceable cartridge containing a plurality of blades, for use in the saw. intellectual property office of N.Z. 29 AUG 2006 RECEIVED P:\OPER\RSHU 282583Q-C AP.doc-28/08/06 Advantageously the blades within the cartridge are subject to a spring bias to present successive blades to a READY position for co-operation with the feed means.

In the form in which the feed means is operable to return a blade from the operative 5 position to the cartridge for storage, the feed means is operative to return that blade to the READY position in the cartridge.

The jigsaw in accordance with preferred embodiments of the present invention can be safely and conveniently stored without the sharp and dangerously pointed metal blade 10 being visible or accessible. When left in this condition by the simple operation of the feed means the saw blade has been disconnected from the driving mechanism and is safely stored either automatically or manually. Inadvertent or accidental operation of a saw with the blade thus stored presents little, if any, danger to the operator, but in any event provides a significant contribution towards intrinsic safety.

In a particularly preferred embodiment, it is a matter of choice whether the same blade is re-installed for a subsequent use, or whether it is ejected and replaced with a new blade using the slider-operated mechanical system discussed previously, and this can be achieved by means of a simple two stroke operation. On the first, or down-stroke, the blade is 20 removed from the driving mechanism. At the bottom of the down-stroke a decision is required if the blade is to be replaced. The existing blade can be allowed to fall free of the saw or be stored within the cartridge for a subsequent use. In either case the saw may now be configured in safe mode by completing an up-stroke. It can now be stored or rested in complete safety in a convenient 'foot plate down' orientation.

On a second two stroke operation of the slider, at the down-stroke the feed means takes the blade from the READY position. If a used blade has been returned to the cartridge, then this will be taken, because it was stored in the READY position. If the used blade had been ejected when the saw was placed in safe mode, then a new blade will have been (intellectual property office of n.z. 29 AUG 2006 P:\0PER\RSH\12825830.CAP.doc-28/08/06 positioned in the READY position. On the up-stroke of the slider the selected blade is positioned and clamped in the driving mechanism and the saw is again ready to be used. Thus there is no requirement to use any other tool to remove or replace the blade.

Embodiments of the invention will now be further described, by way of example, with reference to the accompany drawings, in which: Figure 2 is a partly exploded perspective view of a jigsaw in accordance with the invention and showing a blade feed mechanism and blade cartridge; Figure 3 is a schematic view of the blade cartridge; Figure 4 shows schematically a blade clamping mechanism associated with the output member of the driving mechanism of the jigsaw; and Figure 5 shows a conventional jigsaw blade.

Fig. 2 shows a jigsaw of one preferred embodiment with a replacement blade cartridge 6 15 shown removed from the tool. It is preferred that the cartridge 6 contains a plurality of blades 8 and that all the blades in the cartridge are of the same type. Advantageously, different cartridges contain blades of different type and the cartridges are easily interchanged so that when changing from working one type of material to another, e.g. changing from wood to metal, a suitable blade can be loaded by changing the cartridge. 20 The cartridge 6 is positioned at the front of the saw adjacent to the final stage of the driving mechanism so that it is proximate to the point of use of the blade. In one form, the cartridge is constructed to 'snap-in' into its operative position on the saw body, and to be removable by depressing a pair of spring loaded sliders. In other forms, the cartridge may be secured by other means such as screws, catches, clips or captive thumbscrews. The 25 attachment system is such as to achieve secure fastening of the cartridge while enabling a quick and convenient release action.

Within the cartridge 6 there is a plurality of blades 8. If there is capacity for 'N' blades in the cartridge, then TSf-l' blades are maintained in close contact with each other in a storage intellectual property office of n.z 29 AUG 2006 P:\OPER\RSH\l 2825830-C AP.doc-28/08fl)6 zone 'A' by means of spring loading in the direction of a first orthogonal axis, designated 'X'. In the direction of a second orthogonal axis 'Y', and a third axis 'Z', the 'N-l* blades in storage position 'A' are restrained from moving by the inner walls of the cartridge. In general there is no requirement to move any blade in direction 'Z' until after it has been 5 removed from the cartridge. As the cartridge is progressively emptied the number of blades which occupy zone 'A' will correspondingly reduce to 'N-2', rN-3' etc. There is sufficient space in zone 'A' for at least 'N' blades, so that even when a cartridge is unused there is space within it to store an additional blade which may be a used blade that is already in the driving mechanism of the tool when the new cartridge is installed. Thus a 10 new cartridge which has 'N' blades pre-loaded into it, has a total capacity of at least 'N+l' blades.

The cartridge 6 also features a second blade storage position, or READY position, designated 'B'. In this position the next blade to be loaded is stored. In an unused cartridge 15 this will be an unused blade initially. The cartridge stores blades in a similar manner to some electronic memory systems which are often referred to as 'last in, first out' storage.

When a blade is to be loaded into the saw, it is removed from READY position 'B' by the blade feed mechanism described below, which withdraws it out of the cartridge in 20 direction 'Y' and secures it in the driving mechanism ready for use. The mechanism which withdraws it from the cartridge also causes a subsequent blade to be promoted from storage zone 'A' into READY position 'B' by moving it in direction 'Y'. This process will be reversed each time the blade currently in use is returned to the cartridge for safe storage in READY position B so that the tool itself will be in a safe storage mode. In the storage 25 mode, the blade which previously occupied READY position 'B' is returned to zone 'A' and the blade previously in use again becomes the next blade to be loaded because it is stored in READY position 'B'. When the blade in use becomes no longer serviceable it can be discarded, as described below. Accordingly the blade which last moved from zone 'A' into READY position 'B' will be the blade next to be loaded into the tool. intellectual property office of n.z. 29 AUG 2006 P:\0PER\RSH\12825830-C AP.doc-28/08/06 The blade feed mechanism is manually operated for example by a reciprocating slider 10 on the body of the saw. While the slider 10 is in the uppermost limit of its travel, i.e. a rest position, it is restrained by a safety catch to prevent inadvertent or accidental movement.

When the catch is manually released and the slider 10 is operated in a downward motion, the blade within the saw is first clamped within the feed mechanism and then released from the driving mechanism. At an intermediate point in the movement before the blade has been offered to the cartridge 6 for storage, an option exists to release the clamp on the blade. This function may be accomplished by depressing a button on the slider 10, which 10 allows the blade to be removed, or preferably to fall free of the tool. This function of changing the blade is preferably an option which is available only at one point of the cycle, which may for example coincide with the limit of downward travel of the slider 10. A second safety catch (or the first-mentioned catch) may also be operative at this point. From this limit point the slider 10 is returned upwards to activate the storage function, 15 during which operation the blade, if a blade is clamped in the feed mechanism, is offered to READY position B of the cartridge. As the slider 10 reaches the upper limit of its travel, the blade is moved into READY position B of the cartridge, and the clamp on the blade is released.

To prepare the tool for its subsequent use, the slider 10 is again operated in a downward movement followed by an upward movement. The blade in READY position B of the cartridge is clamped in the feed mechanism, transferred to the driving mechanism and fixed in it. At the same time as the blade is being removed from READY position B of the cartridge, it is replaced by the next blade from storage zone A.

The means for locating and securing the blade to the driving mechanism is preferably a "quick-operate" system which can be operated readily by an element activated by the slider, but which moves with transverse motion with respect to the normal motion of the reciprocating output member of the driving mechanism. As shown in Figure 4, it operates intellectual property office of n.z. 29 AUG 2006 RCfciwcrt P:\OPER\RSH\l 2825830-C AP.doc-28/08/06 a spring-loaded securing pin 12, mounted on a pivotal carrier 14 which is attached to the reciprocating output member 16 of the driving mechanism. The output member 16 also carries a fixed pin 18. A conventional blade (see Figure 5) has at its driven end a slot 20 which is open to the end of the blade, and a through-hole 22 located between the slot and 5 the working part of the blade. The preferred embodiment is designed to be compatible with conventional blades employing this arrangement. Accordingly in the preferred embodiment, the operation of the slider 10 causes the slot 20 of the blade to engage with the fixed pin 18 on the output member 16 and subsequently by a pivoting motion of the blade about the fixed pin, to align the through-hole 22 in the blade with the centreline of 10 the pin 12, the pin 12 and its carrier 14 having previously been swung outwardly against its spring loading, by the motion of the slider 10 or by the quick release button, to allow any existing blade to be removed. At the point in the cycle when the hole 22 in the blade is aligned with the pin 12, the carrier 14 is released from the slider 10 and is moved by its spring loading to its closed position in which the two pins and the spring tension on the pin 15 carrier 14 form an effective clamp on the blade.

In an alternative embodiment, the blade in use is not automatically stored within the cartridge, but is allowed to fall free from the saw and be manually stored in the cartridge for re-use if required. The operation is similar to that which is described above with the 20 exception that in the first movement of the slider, which is in a downward direction, the blade is released from the saw. As the slider is moved upward a new blade is removed from the cartridge and fixed into the driving mechanism. In this embodiment, a further rest or safe position of the slider is at the lower limit of its travel, and a catch is provided here in addition to the catch at the upper position. Provision is made for the discarded blade to 25 be manually returned to the cartridge for use at some future time. This blade can be either the next blade to be installed, or the last blade to be installed in a similar fashion to electronic storage of the 'last in, first out' and 'last in, last out' types, respectively. intellectual property office of n.z. 2 9 AUG 2006 De/M-ii#r"P% P:\OPER\RSH\1282583Q-C AP.doc-28/08/06 The preferred embodiments of the present invention overcome the difficulties discussed at the outset by allowing the operator to store the blade within the cartridge at the conclusion of every use. Even if there is only a short time break, to make an adjustment between successive uses, the mechanism is simple and can be operated quickly.

Modifications are possible within the scope of the invention.

Throughout this specification and claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" or "comprising", will 10 be understood to imply the inclusion of a stated integer or group of integers or steps but not the exclusion of any other integer or group of integers.

Wllectual property office i of n.z 1 29 AUG 2006

Claims (15)

P:\QPER\RSH\12825830-C AP.doc-28/08/06 - 10- THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

1. A power-operated jigsaw having a removable cartridge for storing a plurality of blades, and blade feed means for removing a blade from the cartridge and feeding it to a 5 driving mechanism of the saw to permit the blade to be coupled to the driving mechanism in an operative position for use of the saw, the blade being removable from the driving mechanism for storage in the cartridge for re-use.

2. A jigsaw according to claim 1, wherein the blade feed means is actuable to return 10 the blade from the operative position into the cartridge for storage when the saw is not in use.

3. A jigsaw according to claim 1 or claim 2, wherein the blade feed means is selectively operable alternatively to remove a used blade from the operative position and to 15 discard that blade to permit its replacement by a further blade from the cartridge.

4. A jigsaw according to claim 1, wherein the blade feed means is operable to discharge the blade from the saw to permit its manual insertion into the cartridge for storage purposes. 20

5. A jigsaw according to any one of claims 1 to 4, wherein the blade feed means includes a gripper device for releasably holding the blade for movement between the cartridge and the operative position. 25

6. A jigsaw according to claim 5, wherein the blade feed means is manually-operated by a control on the body of the saw.

7. A jigsaw according to claim 6, wherein the manually-operated control is associated with a manually-released safety catch to prevent inadvertent actuation of the blade feed i intellectual property office i OFW.Z 29 AUG 2008 P:\OPER\RSHM2825830-1 spa.doc-i9/09/2(X)7 - 11 - means.

8. A jigsaw according to claim 6 or claim 7, wherein the manually-operated control is a slider operable with a reciprocating action.

9. A jigsaw according to claim 8, wherein the slider is reciprocable in an upwards/downwards direction to effect the actions of removing a blade from the driving mechanism, removing a blade from the cartridge and feeding that blade to the driving mechanism and, optionally, returning a blade to the cartridge.

10. A jigsaw according to any one of claims 1 to 9, wherein the driving mechanism includes a clamping system for clamping a blade in its operative position, the blade feed means co-operating with the clamping system to enable clamping and release of a blade during operation of the feed means.

11. A removable cartridge for use in a jigsaw according to any one of claims 1 to 10, the cartridge containing a plurality of blades, for use in the saw.

12. A cartridge according to claim 11, wherein the blades within the cartridge are 20 subject to a spring bias to present successive blades to a READY position for co-operation with the feed means.

13. A cartridge according to claim 11 or claim 12, in which the cartridge when supplied for use is loaded with fewer blades than the maximum capacity of the cartridge whereby an 25 existing blade in the jigsaw can be loaded into the cartridge.

14. A jigsaw substantially as hereinbefore described with the accompanying drawings. reference to Figures 2 to 4 of intellectual property" officf of n.z 2! SEP 2007 RECEIVED P:\OPER\RSHU 2825830-1 spadoc-19/09/200? - 12-

15. A removable cartridge substantially as hereinbefore described with reference to the accompanying drawings. END OF CLAIMS INTELLECTUAL property offiof of n.z 2 ! SEP 2007 R E C EIV ED