WO2012097409A1

WO2012097409A1 - Method and means to effect caulking removal

Info

Publication number: WO2012097409A1
Application number: PCT/AU2012/000037
Authority: WO
Inventors: Kevin Ross Inkster
Original assignee: Arbortech Industries Limited
Priority date: 2011-01-19
Filing date: 2012-01-19
Publication date: 2012-07-26

Abstract

A cutting tool (1) for cutting out material (22) between two edges (19 and 20) is disclosed. The cutting tool (1) has two spaced apart blades (9 and 10) each with a cutting edge (11, 12) extending therealong. The cutting edges (11, 12) are spaced apart at least for a substantial distance along their length. The cutting tool (1) imparts an oscillatory motion in the cutting edges (11, 12) to cut the material (22) from between the two edges (19 and 20), simultaneously. The cutting tool is useful for removing caulking from between adjacent building panels. Various types of cutting blades (9 and 10) are described.

Description

"Method and means to effect caulking removal"

Field of the Invention

This invention relates to caulking removal and to an apparatus to effect such removal and to an installation where caulking has been so removed.

Background Art

Caulking Is used to fHI and seal gaps between adjacent faces of buildings where the distance between the faces might vary over time so that resiliency in caulking can maintain a useful seal.

However, materials currently useful for caulking can be expected to lose a lot of the resiliency over a time period which is much less than the expected life of the structure providing the gap to be filled.

Such structures can include conventional masonry materials, cement based materials, and any of these where one of the sides is provided by wooden or aluminium or steel frame.

When effectively replacing the caulking from time to time, the caulking must be scoured from the gap and substantially removed from the surfaces to which It has adhered, prior to replacing the old caulking with fresh caulking material.

Currently, caulking is removed by using a cutting blade which is moved with some form of cutting action which is then positioned and forced to cut between one side of the caulking and the surface to which it is adhering in a first instance, and then to repeat this down a second side then effectively taking the caulking out from between the caulking space defining halls. This process is considered to be both arduous and slow and it is a problem to which this invention is directed.

The preceding discussion of the background art is intended to facilitate an understanding of the present invention only. It should be appreciated that the discussion is not an acknowledgement or admission that any of the material referred to was part of the common general knowledge as at the priority date of the application.

Throughout the specification unless the context requires otherwise, the word "comprise" or variations such as "comprises'' or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers. Throughout the specification unless the context requires otherwise, the word "include" or variations such as Includes^* or "including", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

Disclosure of the Invention

My proposal is to use two cutting blades which are caused to be operated with some cutting action where cutting edges of the respective blades are spaced apart and able to be maintained to an extent that they will effect cutting respectively at respective interface between the caulking and a respective wall defining the caulking space.

The cutting action of the blades may be oscillatory, reciprocating linearly or reciprocating about a pivot point so as to prescribe an arcuate movement, or oscillatory so that the cutting action of the blades is elliptical, preferably with a downforce on the blade being applied during the cutting stroke of each blade. The cutting action of the blades is preferably out of phase.

By using two blades, and having these operating both with a cutting action at the same time and either having the blades themselves shaped so that they can be urged into a gap to an extent that the cutting edges will both bear with a cutting action against the respective side of a caulking space or by reason of resilient outward pressure, will effect a location of the cutting edges at a location at the interface between the caulking and the respective space defining the caulking space, has shown itself to improve significantly the efficiency with which caulking can be removed.

In preference, the cutting action of the respective blades is substantially elliptical having an action provided by cutting devices as disclosed in my earlier patents and patent applications, namely W01992 D14587 and WO2011/044615, the contents of both of which are incorporated herein by cross reference.

In preference, the blades are caused to move through a similar extent and along a simflar pattern but spaced apart for the purposes of resilientiy bearing against the side walls of the space defining the caulking area or having a tapering algnment where an operator can position the respective blades to an extent that the two sides which is to say the cutting edges of the respective blades are engaging closely to or against the respective sides defining the caulking space. The two cutting blades are preferably spaced apart from each other substantially along the length of the cutting edges, however in a preferred form the blades may contact at a toe portion thereof. In a particularly preferred form, the blades may come into contact close or near contact at the toe portion thereof, and the cutting edges may diverge from each other from their toe portions to lie parallel or near parallel to each other toward the heel of each blade. This described arrangement is when the blades are viewed from their edge or in bottom plan view.

Also in accordance with a preferred feature of the invention the cutting edges of each blade may be arcuate in shape when viewed from the side.

In preference, where the side defining a caulking space is masonry, there is some advantage in having teeth providing the cutting surface which extends generally transversely to an alignment of the blades so that the cutting action itself with these orthogonally aligned teeth portions will abrade against the surface having the effect of additionally removing remaining caulking adhesions leaving the surface of the masonry face further cleaned.

In preference, by using the action of my previously described cutting action where the respective two blades are caused each to be driven through an approximately elliptical motion has the result in practice of being able to guide the respective teeth over the caulk surface and then bring these teeth down against the caulk material and in effect help to drag this out from the caulking space.

In one form of the invention therefore it could be said to reside in a method of caulking removal which includes an apparatus arranged to be driven with two juxtaposed cutting blades each having at least a reciprocating cutting action generally planar of the respective blade where the cutting edges of the respective blades are spaced apart to an extent that they will respectively engage respective sides at the same time of a caulking defining space with caulking therein and effecting entry between the sides of the caulking defining space, both blades operating at the same time with such reciprocation action for both blades to effect separating of the caulking from a respective side wall and thereby assisting removal of the caulking thereby.

In another form, the invention could be said to reside in an apparatus arranged to drive two juxtaposed cutting blades with each at least a reciprocating cutting action where the cutting edges of the respective blades are spaced apart to engage both sides of the caulking defining space with caulking therein at the same time.

In a further alternate form, the invention could be said to reside in a cutting tool comprising two cutting members positioned side by side, spaced apart, and each having a tooth cutting edge being of approximately the same shape, each cutting member being mounted on respective eccentrics of a drive shaft coupled to a motor, each cutting member being guided by respective control links so that the cutting edge of each cutting member prescribes simultaneously in a plane of the toothed edge, simultaneous oscillatory motions in the direction of the toothed edge and in a direction substantially at rights angles thereto, with corresponding movements of the respective cutting members being out of phase, and the teeth of each cutting edge being adapted to each cut when moving individually in the direction of the toothed edge, the two adjacent blades being where the blades are supported and adapted to be driven with a relative oscillatory motion and with the toothed cutting edge at an outer edge of each respective blade, the two blades being aligned one with respect to the other with one end of the cutting edge of a first of the blades being closer to an adjacent end of the second blade than the opposite end of the respective blades.

In preference, each blade is resHiently bendable to faciftate positioning between a caulking space when therein to effect an outward resilient pressure of the respective cutting edges against the respective faces defining the caulking space.

In preference, the blades are each adapted to bend so as to provide coming together of the cutting edges during use.

In an alternate form, the shape of the cutting edge of each blade is convex.

In preference, the cutting edge of at least one of the blades is serrated.

In preference, the cutting edge of at least one of the blades is toothed with each tooth projecting only to an outer side of the blade.

In a further form the invention could be said to reside in a method of removing caulking from between adjacent faces defining a caulking space, the method including the steps of:

introducing a cutting tool to the caulking between the adjacent faces between which the caulking is embedded, the cutting tool comprising two cutting members positioned side by side and each having a cutting edge and being of approximately the same shape, each cutting member being mounted on respective controllings of a drive shaft coupled to a motor, each cutting member being guided by respective controllings so that the cutting edge of each cutting member prescribed simultaneously In the plane of the toothed edge, simultaneous oscillatory motions in the direction of a toothed edge and in the direction right angles thereto, with corresponding movements of the respective cutting members being out of phase, and the teeth of each cutting edge being adapted to each cut when moving individually in the direction of the toothed edge, the two adjacent blades being where the blades are supported and adapted to be driven with a relative oscillatory motion with the tooth cutting edge at an outer edge of each respective blade, the two blades being aligned, one with respect to the other with one end of the cutting edge or the first of blades being closer to an adjacent end of the second blade than the opposite ends of the respective blades. In preference, where the caulking Is between one side which is not of masonry or cement, the cutting surface of the blade comprises a sharpened edge without specific teeth forming in the actual surface of the cutting edge.

In preference, the blades can be respectively offset to a first drive axis to facilitate removal of caulking by one side of the face restricting access thereto of a cutting machine.

Specifically, in accordance with one aspect of the present invention there is provided a cutting tool for cutting out material between two edges, the cutting tool having two spaced apart blades each with a cutting edge extending therealong, the cutting edges being spaced apart at Ieast for a substantial distance along their length, the cutting tool imparting an oscillatory motion In the cutting edges to cut said material from between said two edges simultaneously.

Preferably the cutting too has two juxtaposed spaced apart blades.

The edges may be defined in the sense that they constitute edges between a gap between building panels or glass in which caulking material is located, or defined notionally in the sense that they prescribe a pair of substantially parallel lines to be cut in a panel where the material therebetween is to be removed.

By oscillatory, the cutting action of the cutting edges may be reciprocating linearly or arcuately about a pivot, or oscillating In an elliptical motion. Preferably the cutting action of the blades is out of phase. Most preferably the cutting action of the blades is out of phase by 180 degrees.

Preferably the two cutting blades are arcuate in shape when viewed from the side, having a convex shaped cutting edge from toe to heal.

Preferably the cutting edges are spaced apart from each other substantially along the length of the cutting edges, and taper towards each other towards the toe. This arrangement is when the blades are viewed edge-on.

Further, preferably the blades may contact or nearly contact at the extremity of the toe portion thereof.

Still further, preferably the cutting edges taper in a curved taper substantially along the length of the cutting edges towards each other towards the toe, so the blades are closer together toward the toe. The blades may come into contact or near contact at the toe portion thereof.

Preferably the cutting edges are spaced apart from each other to lie parallel or nearly parallel to each other toward the heel of each blade, and taper in a curved taper substantially along the length of the cutting edges towards each other towards the toe to come into contact or near contact at the toe portion thereof. In effect, with this arrangement, the cutting edges may diverge from each other from their toe portions to lie parallel or near parallel to each other toward the heel of each blade. This described arrangement is when the blades are viewed from their edge or in bottom plan view.

Alternatively, the blades are resiliently flexible so that the cutting edges away from the toe may under compression be urged toward each other, to lie parallel or nearly parallel to each other toward the heel of each blade as the blades are urged toward each other. The blades would be urged toward each other as they are inserted into the gap between adjacent panels in which caulking is contained. The gap would be narrower than the blades spacing toward the heel, when not under any compressive load. With this arrangement, the blades are brought to parallel or near parallel disposition by the compressive pressure exerted as the blades are forced between the gap; the blades need to be inserted into the gap, in use, sufficiently so that this parallel or near parallel disposition is achieved.

In all of these arrangements, once the blades are inserted Into the caulking and the de-caulking cutting operation is underway, the cutting tool cuts the caulking free from t e edges, and extracts the caulking from within the gap, in a single operation.

Preferably each said blade is mounted to a crankshaft, which is made to rotate by a rotary motion engine, each blade being restrained in a position to provide elliptical motion in said cutting edges. The mount may be by way of a connecting rod or yoke.

Each blade may be restrained in position by resliently deformable straps connecting at one end thereof each blade at a point opposite each journal of said crankshaft and secured at the opposite end thereof at a fixed position to allow reciprocating motion of said point at an angle of from 125* to 145° to a line extending from the axis of the crankshaft to the toes of said blades.

Each blade may be restrained in position by resiliently deformable straps secured at a fixed position spaced from the axis of the crankshaft, opposite from the toes of said blades.

Preferably the cutting edges each oscillate in an elliptical motion substantially in the plane of each respective blade, with the cutting tool applying a downforce during the cutting stroke of each blade and an upforce on the backstroke of each blade.

in an alternative preferred arrangement, the blades are spaced apart by a distance of at least the combined width of each cutting edge.

In a further preferred arrangement, the blades are spaced apart from each other at the extent they are near parallel, a predetermined distance based on the distance apart of the intended cuts. With this arrangement, different blades can be provided when paired to provide differing spacings, and also differing off-sets when using the cutting tool in an awkward position, for example.

In an alternative preferred form of the invention there is provided biasing means between the blades, to urge the blades apart from each other. Such biasing may be provided by a spring loaded thrust washer to urge one or both blades along its their respective crankshaft journal. In an alternative arrangement the biasing is provided through the springy resilience of the blades which allows the blades to be urged together, in operation. Preferably said cutting edge of one or each blade comprises a plurality of teeth located with abrading portions thereof on the outside of the blade, to abrade against a said edge. There is no need for teeth to abrade material between the blades.

Also in accordance with the present invention there are provided blades for a cutting tod as described above.

Preferably, each blade has an arcuate cutting edge extending from a toe to the heel of the blade, supported on a plate portion, and a connecting portion extending from the plane of the plate portion at an obtuse angle, extending between said plate portion and an attaching portion by which said blade is secured to the cutting tool.

The obtuse angle may lie between 170° and 110" but more preferably in the range of from 135° to 165'. Most preferably the ob tuse angle lies in the range from 150'to 160".

Also in accordance with the invention there is provided a method of removing caulking from between two defined edges, comprising steps of setting in operation a cutting tool as hereinbefore described, inserting the toe of the blades of the cutting tool into the caulking, allowing the cutting edge of said blades to cut Into said caulking, pitching said cutting tool to urged said blade cutting edges arcuately in said caulking along said two defined edges, and moving said cutting tool in a direction away from the toes of the blades while maintaining the cutting edges in contact with and immersed in said caulking along said two defined edges to remove the caulking from between the two defined edges.

Also in accordance with the invention there Is provided a method of removing caulking from between two defined edges, comprising steps of setting in operation a cutting tool as hereinbefore described, Inserting the toe of the blades of the cutting tool into the caulking, allowing the cutting edge of said blades to cut into said caulking, urging said cutting tool and blade cutting edges arcuately downward toward the heel of said blades while maintaining the cutting edges in contact with and immersed in said caulking along said two defined edges, and moving said cutting tool in a direction away from the toes of the blades while maintaining the cutting edges in contact with and immersed in said caulking along said two defined edges to remove the caulking from between the two defined edges.

Also in accordance with the invention there is provided a building having panels with caulking removed according to the above described method.

Brief Description of the Drawings

For a better understanding of this invention, preferred embodiments of the invention will now be described with the assistance of drawings wherein:

Figure 1 is a perspective view of functioning elements for a cutter system separated from its housing or drive motor including two juxtaposed blades being used to remove caulking from within a caulking defining space, according to a first embodiment;

Figure 2 is a cross sectional view along the lines A-A-A-A in Figure 1 ;

Figure 3 Is a complete saw according to a second embodiment where juxtaposed cutting blades are aligned with the toe portions closest one to the other, and heel further apart;

Figure 4 is a further view of the first embodiment showing a saw adapted to drive juxtaposed blades in a elliptical cooperative cutting action with the respective blades being inserted where the blades are again lined and positioned so that they have a narrower front gap at a toe portion and a wider rear gap;

Figure 5 is the same view as In Figure 4 with however the blades being inserted further into the caulking defining gap;

Figure 6 is a view from above of the cutting apparatus of figures 4 and 5 showing the positioning and alignment of the two juxtaposed blades;

Figure 7 is a further illustration of a cutting system with two juxtaposed blades according to a third embodiment showing in this case a further position of using the blades in which the two juxtaposed blades are inserted between the spaces defining the caulking space with however on one side the material being wood and one of the blades which is adjacent the wooden side having a planar outer face and a continuous cutting edge instead of cutting teeth;

Figure 8 is a perspective view of the functional elements of the cutting system according to a fourth embodiment with the two juxtaposed blades being mutually offset with an inner blade having a planar continuous cutting edge and an outer blade having a toothed cutting edge;

Figure 9 is a further view of the same arrangement as in Figure 8;

Figure 10 is a schematic showing how a blade with teeth enters between the gap defining the caulking space and Is acting to cut between the caulking on the one side with the teeth protruding to some extent to provide an abrasive effect against that side, according to all of the embodiments;

Figures 11 and 12 are a blade edge view of part of a cutting tool according to a fifth embodiment of the invention;

Figure 13 is a blade edge view of part of a cutting tool according to the fifth embodiment of the invention, but with a set of blades fitted for a wider caulking gap; and

Figures 14 to 16 are a sequence of views showing the operation of the cutting tool according to the fifth embodiment

Best Mode(s) for Carrying Out the Invention

Referring in detail now to the drawings and especially Figures 1 and 2 there is shown mechanism 1 which for the sake of clarity has an outer body removed and the inner functioning elements include separately movable yokes 2 and 3 which are driven by Journals on a crankshaft forming individual eccentric cams. The individual cam 4 for the near side yoke 2 is shown, but the other side Is not shown, being obscured by the illustrated mechanism. The crankshaft (not shown in its entirety apart from the protruding shaft 8) is driven by rotation to effect operation of the eccentric cams.

The rotation of these eccentric cams result in relative movement of the yokes 2 and 3 with an approximately elliptical motion in this case each blade being 180 degrees out of phase but the movement is modified by tethering blades in the form of resilient steel straps 5 and 6 in the other which are secured at apertures 7 to a portion of the main supporting frame, fixed relative to the shaft 8 position.

Two blades formed of plate portions 9 and 10 each having a cutting edge are secured respectively to the yokes 3 and 2. For simplicity, the plate portions 9 and 10 will be hereafter referred to as the two blades 9 and 10. The two blades 9 and 10 are therefore constrained to be driven mainly along a direction of their own elongate length and with an action that provides that its cutting edge 11 formed by teeth 12 will follow a generally elliptical movement at least relative to the main body of the machine 1 driving the blades 9 and 10. Further, the elliptical movement is such that the cutting edge 11 or teeth 12 on the cutting edge is urged downward into the material to be cut, on the cutting stroke, and lifts upward on the reverse stroke. The teeth 12 are arranged so that the blades 9 and 10 operate as a pull saw arrangement, the cutting stroke moving the teeth 12 towards the operator, so that the blade is always under tension when cutting. This provides for greater ease of control compared with an arrangement where the blade might cut in the push stroke, while under compression.

Both blades in this case which are of similar shape which are juxtaposed perform this motion but by reason of the alternate alignment of the relative eccentrics are driven at least In this embodiment 180 degrees out of phase. With the blades being 180 degrees out of phase, when one blade is on the cutting stroke, the other wil be on the reverse stroke.

I have previously described a machine of this type in earlier published patents but in this case I have reshaped and realigned the blades 9 and 10 so that they have an arcuate cutting edge 11 and sufficient body 13 behind the cutting edge 11 to provide support for this, but also that the two blades are shaped relative to one another so that at their outer end which we will refer to as the toe at 14 they are closest together and they are spread apart at a back of the blade or the heel 15 so that there is a relatively wide gap at this location at least between the toothed cutting portions of the respective blades 9 and 10.

The blades 9 and 10 are generally of sheet material and are therefore of a generally planar alignment but are bent at an obtuse angle at 16 to converge toward each other along a connecting portion, which then reverts the spacing back to being somewhat closer to enable them to be joined at their attaching portions at joining location 17 and 18.

The blades 9 and 10 are in this case made from steel that is selected and of a thickness to have an extent of resilience sufficient for the purpose which means that as the blades are projected into the gap, they can be projected further in once a nose 13 has been introduced between the respective sides at 19 and 20 defining a caulking gap 21.

A person operating the machine can therefore insert the respective blades into the gap 21 and both by manipulating the relative position and the degree of force being used to push the blades into the gap 21 effect a close engagement of the respective teeth 12 of the respective blades 9 and 10 to both cut and tear caulking and at the same time provide an abrading action against the side of the masonry defined gap 21.

The caulking in this case 22 will therefore be progressively separated and by reason of the relative action described by the blades 9 and 10 will be caused to protrude out from between the blades.

Figure 3 shows a completed cutting machine 23 according to a second embodiment holding in this case two blades 9 and 10 where the machine 23 has a body 24, a handle 25 and switch 26.

In this case the blades are differently shaped from the first embodiment in that a nose or toe 14 of each respective blade 9 and 10 is quite close together and adapted to be protruded in between even the smallest caulking defining gap 21 and the remaining portions of the blade are increasingly separated at the cutting edge 11 enabling a user to insert the blades together at their toe 14 and continue to insert until the cutting edges 11 and blades body 13 are fully engaging against mutually their respective sides 19 and 20 of the cauking defining gap 21.

Figures 4 and 5 show the first embodiment where the cutting machine 23 includes blades 9 and 10 shaped and spaced apart as in Figures 1 and 2 and the caulking gap 21 is between masonry facings 19 and 20. The action shown is at first in Figure 4 where the tip 14 of the blades 9 and 10 is inserted into the caulking within the caulking gap 21 and then as shown specifically in Figure 5, blades are continued to be pushed deeper with the respective widened gap between the blades 9 and 10 toward the heels thereof so that the toothed cutting edges 11 in the case of blade 10 wiH be brought to bear against the side face with both a cutting of the caulking and an abrading effect on the masonry facing of masonry facing 19.

Figure 6 is a view from above of the machine 23 shown in Figures 4 and 5 with the shape of the blades 9 and 10 being more apparent in that they diverge from the nose 14 to an extent that will allow for selected insertion to match expected gap sizes and ensure that, the toothed edges win engage fully against the side walls defining a caulking gap.

Figure 7 illustrates a third embodiment of a cutting machine 23. This embodiment is similar to the previously described embodiments except in two respects. This embodiment has blades formed with a fixed spacing near the foot, and in addition, this case one of the blades 40 has a cutting edge which is a continuously curved sharpened edge (not shown) without teeth. The compares to the other blade 41 which has a cutting edge with teeth 42 that project both downwardly and out to a side to effecting an abrading surface. The blade 40 is adapted to be used against non-masonry surface as in 43 which might be damaged by a blade with teem. This surface 43 in this case can be a wooden post (or in another case a steel or aluminium member) so that the cutting edge which will not provide an abrading effect and simply cuts through the caulking without abrading the surface and therefore causing its deterioration unduly.

Figure 8 illustrates a fourth embodiment of the cutting machine with the body and motor omitted for clarity. In this embodiment, the blades 10 and 46 are mutually off-set to the left so that the action of the blades 10 and 46 of the cutting machine 23 can be positioned with blade 0 very close to one side wall and still effect a relatively linear action by the respective blades. The off-set means that the cutting machine 23 body (and mechanism 1 housing) will avoid interference with a side wall extending outward to the immediate left of the cutting machine 23, where de-caulking is to take place where the side wall and a wall panel meet at right angles. It will be understood that blades with an opposite mutual off-set (to the right) can be provided where the cutting machine 23 is to de-caulk where a side wall and a wall panel meet at right angles and the side wall is extending outward to the immediate right of the cutting machine 13.

In this embodiment, the operating parts are shown, namely the yokes 2 and 3, drive shaft 8 and cams and tethering blades 5 and 6. The shaft 8 and mounting points 7 are held relative to each other to effect elliptically 180* out of phase relative movement of the blades 10 and 46 with the major elliptical axis running roughly along the length of the blades. Blade 46 has a cutting edge 48 which is a continuously curved sharpened edge without teeth. The blades are shaped along their length from a sheet of material with angular bends at for instance 57, 58 in the case of blade 46, and 59 and 60 in the case of blade 10. Blade 0 is similar to the blade illustrated in the first embodiment, except that the angles of the bends are more acute in order to exaggerate the offset of blade 10. Blade 46 is angled with opposite offset to that 6hown in the other embodiments.

The action of the mechanism 1 of this embodiment is the same as the first embodiment, that is generally driving the motion of the blades in an elongate direction of the blades to allow relative out of phase movement between the two. A further view of this same arrangement is shown in Figure 9.

In Figure 10 the elliptical cutting action of the blades of all of the embodiments is shown. Figure 10 shows the caulking gap 21 with one side 19 removed, leaving the other side 20 in place, and one of the blades 10, the closer one, cut away.

The nose or toe 14 of the far blade 9 is shown projecting substantially into the gap 21. Both blades 9 and 10 have a cutting edge 11 having teeth 12 which are arranged to abrade on the exposed edge and up the outsides of the blades 9 and 0 (and not the sides of the blades that face each other. The ellipse illustrated with the arrowhead on the inner surface of the blade 9 shows the path taken by the blade when in operation.

Referring to figures 1 to 16, a fifth embodiment is illustrated. This embodiment is similar to the first embodiment, except that the blades 9 and 10 are manufactured to be more resilient. This can be achieved through use of thinner spring steel or placement of apertures in the blade material, or a combination of these features. As with earlier embodiments, the blades 9 and 10 are closer together at the nose/toe area 14 and spread apart towards the rear or heal 15. Both by reason of their relative positions and the fact that they are also able to be sprung together under resident pressure means that they act with co-operation to enable the teeth 12 to be inserted to a sufficient extent so that they will always bear against the actual sides of the caulking gap 21.

Figure 1 shows a point in time after insertion of the toes 14 of the blades 9 and 10 into old caulking contained within the caulking gap 21. Figure 12 shows the blades 9 and 10 fuKy inserted into old caulking contained within the caulking gap 21, and compressed toward each other resulting in the blades urging against the sides of the masonry 19 and 20, assuming a closer to near-parallel relationship with each other and with the sides of the masonry 19 and 20 at the edges of the masonry 19 and 20, and hence a closer cut, especially when the tool is rotated in operation, as will be described later.

Figure 13 shows a different set of blades having a wider spacing including a wider spacing at the toe 14, fully inserted into old causing contained within the caulking gap 21 between opposed masonry surface edges 19 and 20. These blades are intended for use between opposed masonry surface edges 1 and 20 that are spaced further apart than in the installation illustrated in figures 11 and 12. As can be seen, the blade 9 and 10 lie against adjacent masonry 20 and 19 respectively, allowing the teeth 12 on the blades 9 and 10 to abrade against the masonry and so provide a cleaned surface for new caulking to adhere, when the new caulking is introduced. It will be understood that many different blade spacings are possible, to suit different caulking gaps, and sets of blades can be provided to be fitted to the caulking fool 23.

Referring to figures 14 to 16, a sequence showing operation of the cutting tool to remove caulking from the caulking gap 21 between adjacent masonry panels is shown. In these figures, the body of the cutting tool has been omitted, but the disposition of the resilient steel straps 5 and 6, apertures 7, and shaft 8 which fix the mechanism 1 relative to the body, show the pitch of the cutting tool in operation. The operation of the cutting tool 23 to remove caulking commences with the setting in operation of the cutting tool 23 and inserting the toe 14 of the blades 9 and 10 of the cutting tool into the caulking as shown in figure 14. The cutting edge 11 (teeth 12) of the blades 9 and 10 are urged inward to cut into the caulking until the blades reach the position shown in figure 15. The resilience of the blades 9 and 10 results in the blades urging apart, away from each other, to impart a sideways force against the masonry 19 and 20.

Referring to figure 14, the blades 9 and 19 each meet a connecting portion 63 at an obtuse angle 16, the connecting portions 63 of the blades then converging toward each other to be closely spaced where they are joined by an attaching portion 65 to the joining location 17 and 18. The joining locations 17 and 18 each comprise a bracket 67 which pins with in-hex machine screws 69 the attaching portion 65 of each blade 9 and 10 to respective yokes 2 and 3. Once the blades are inserted as described above, then the cutting tool is pitched to a position as shown in figure 16, to raise the toes 14 of the blades 9 and 10 relative to the heels 15 of the blades 9 and 10, by pivotally urging the cutting tool and blade cutting edges arcuately downward while maintaining the cutting edges in contact with and immersed in the caulking along the edges 19 and 20 of the masonry. In this position, the blade toes 14 are urged apart, as seen in figure 13.

When in this position, the cutting tool is slid linearly downward with the toes 14 of the blades 9 and 10 trailing the cut. The cutting edges 11 and outer surfaces of the teeth 12 are maintained in contact with the masonry 19 and 20 and immersed in said caulking along the masonry 19 and 20 for the duration of the operation, to remove the caulking from between the masonry 19 and 20. The blades 9 and 10 have a cutting direction which runs from the heel 15 to the toe 14, resulting in the blades 9 and 10 being under sRght tension during the cutting stroke of each blade.

The de-caulking with the manner of operation of the cutting tool has been found to be very efficient and substantially faster than has hitherto been the case with prior art arrangements, however an additional benefit is that the sides of the caulking gap are to some extent further polished or cleaned up. The invention has shown to be of some significant benefit in rapid removal of unserviceable caulking needing to be removed and replaced with new caulking material.

The invention can reside in a method of removal which incorporates the steps of inserting into a caulking gap blades having a relative reciprocal or oscillatory motion and, by reason of their width or by reason of the resiliency or both, can be caused to bear against the sides of a caulking gap and effect removal thereby. Throughout this specification the purpose has been to illustrate the invention and not to limit this.

Claims

The Claims Defining the Invention are as Follows

1. A cutting tool for cutting out material between two edges, the cutting tool having two spaced apart blades each with a cutting edge extending therealong, the cutting edges being spaced apart at least for a substantial distance along their length, the cutting tool imparting an oscillatory motion in the cutting edges to cut said material from between said two edges simultaneously.

2. A cutting tool as claimed in claim 1 wherein the spaced apart blades are Juxtaposed.

3. A cutting tool as claimed In claim 1 or 2 wherein the oscillatory motion is an elliptical motion, and the cutting action of the blades is out of phase by 180 degrees.

4. A cutting tool as claimed in any one of the preceding claims wherein the two cutting blades are arcuate in shape when viewed from the side, having a convex shaped cutting edge from toe to heal.

5. A cutting tool as claimed in any one of the preceding claims wherein the cutting edges are spaced apart from each other substantially along the length of the cutting edges, and taper towards each other towards the toe.

6. A cutting tool as claimed in any one of the preceding claims wherein the blades contact or nearly contact at the extremity of the toe portion thereof.

7. A cutting tool as claimed in any one of the preceding claims wherein the cutting edges taper in a curved taper substantially along the length of the cutting edges towards each other towards the toe, so the blades are closer together toward the toe.

8. A cutting tool as claimed in any one of the preceding claims wherein the blades are resiliency flexible so that the cutting edges away from the toe may under compression be urged toward each other, to lie parallel or nearly parallel to each other toward the heel of each blade as the blades are urged toward each other.

9. A cutting tool as claimed in any one of the preceding claims wherein each said blade is mounted to a crankshaft, which is made to rotate by a rotary motion engine, each blade being restrained in a position to provide elliptical motion in said cutting edges.

10. A cutting tool as claimed in claim 9 wherein each blade is restrained in position by a resiDently deformable strap connecting at one end thereof each blade at a point opposite each journal of said crankshaft and secured at the opposite end thereof at a fixed position to allow reciprocating motion of said point at an angle of from 125" to 145* to a line extending from the axis of the crankshaft to the toes of said blades.

11. A cutting tool as claimed in claim 10 wherein each blade may be restrained in position by resilientiy deformable straps secured at a fixed position spaced from the axis of the crankshaft, opposite from the toes of said blades.

12. A cutting tool as claimed in any one of the preceding claims wherein the cutting edges each oscillate in an elliptical motion substantially In the plane of each respective blade, with the cutting tool applying a downforce during the cutting stroke of each blade and an upforce on the backstroke of each blade.

13. A cutting tod as claimed in any one of the preceding claims wherein the blades are spaced apart by a distance of at least the combined width of each cutting edge.

14. A cutting tool as claimed in any one of the preceding claims wherein the blades are spaced apart from each other at the extent they are near parallel, a predetermined distance based on the distance apart of the intended cuts.

15. A cutting tool as claimed in any one of the preceding claims wherein there Is provided biasing means between the blades, to urge the blades apart from each other, the biasing being provided through the springy resilience of the blades which allows the blades to be urged together, in operation.

16. A cutting tool as claimed in any one of the preceding claims wherein said cutting edge of one or each blade comprises a plurality of teeth located with abrading portions thereof on the outside of the blade, to abrade against a said edge.

17. A blade for a cutting tool as claimed in any one of the preceding claims. A blade as claimed in claim 17 having an arcuate cutting edge extending from a toe to the heel of the blade, supported on a plate portion, and a connecting portion extending from the plane of the plate portion at an obtuse angle, extending between said plate portion and an attaching portion by which said blade is secured to the cutting tool.

A blade as claimed in claim 18 wherein the obtuse angle lies between 170" and 110°.

A method of removing caulking from between two defined edges, comprising steps of setting in operation a cutting tool as claimed in any one of claims 1 to 16, inserting the toe of the blades of the cutting tool into the caulking, allowing the cutting edge of said blades to cut Into said caulking, pitching said cutting tool to urged said blade cutting edges arcuately in said caulking along said two defined edges, and moving said cutting tool in a direction away from the toes of the blades while maintaining the cutting edges in contact with and immersed in said caulking along said two defined edges to remove the caulking from between the two defined edges.