GB2338502A

GB2338502A - Filling and grouting device

Info

Publication number: GB2338502A
Application number: GB9813394A
Authority: GB
Inventors: Nigel Anthony Chute
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-06-20
Filing date: 1998-06-20
Publication date: 1999-12-22
Also published as: GB2338503A; GB9813394D0; GB2338503B; GB9914125D0

Abstract

A filling and grouting device for use in home improvements and interior decoration projects. Said device consists substantially of a rigid handle (205) bonded to a flexible work head (207), wherein said handle provides means for applying a compressive load on any filling or grouting materials via a work head, and is simultaneously dragged along the surface of said filling materials. Said compressive load is spread across the surface of the siad flexible work head and causes the filling materials to be smooothly and evenly rendered.

Description

CHW-PO4-Gil 1 1 k 2338502 1 Manually Operable Tool The present invention

relates to a manually operable tool, having a rigid handle, a method of using said tool and a method of manufacturing said tool.

During the course of home improvements projects, it is frequently necessary to carry out certain preparatory work prior to the application of paint, wallpaper and the like. Such preparatory work often involves a variety of filling operations, to be carried out on all kinds of holes, gaps, joins and cracks. The substances used for such tasks are usually proprietory fillers, grouts and other sealants, which generally consist of particles in a waterbased solution.

A number of tools are known which are intended to apply such substances and include a variety of filling knives, spatulas and spreaders.

These devices are generally configured as semi-flexible blades of material, usually manufactured in metal or plastics. By the application of downward pressure when combined with a drawing action along the area to be filled, some application and finishing of the filling substance can be achieved.

A problem with such devices is that their blades tend to be insufficiently flexible to achieve satisfactory results in the majority of applications. This is because such blades are essentially sheets of semi rigid material, and as such they will deflect in one plane only. A consequence of this is that it is difficult to achieve a uniform compression and smoothing action on the surface of the wet filler, particularly in corners or locations having an irregular background.

in view of the shortcomings of such devices, it is not unusual for a person engaged in decorating work to use their own fingertip for purposes of filling, grouting and the like. This method has a number of advantages.

The fingertip gives sustained and even pressure on the surface of the filler, CHU-P04-GR r - 2 the filler can be applied precisely across gaps of different widths and a very smooth finish can be achieved.

Unfortunately, the skin which covers a human fingertip cannot withstand the drying and abrasive effects of both the filling materials being applied and of the rough edges and surfaces of the adjacent gaps and joins for long. The fingertip may become sore or otherwise injured, which may have the effect of seriously impairing the person's ability to complete not only the filling and grouting operations, but any further decorating tasks.

According to a first aspect of the invention, there is provided a manually operable tool, comprising a rigid handle and a flexibly deformable work head attached to said handle, wherein said work head provides a substantially continuous curvilinear work surface.

Preferably, a flexibly rigid spline extends from said handle and said work head is bonded to said spline. The handle may be substantially similar to a paint brush handle and the curvilinear work head may be convex in shape, preferably having a profile substantially similar to that of a human fingertip.

Preferably, the. head is a thermoplastic elastomer material R 6.

which may be Evopre In a preferred embodiment, the curvilinear work surface has a fine textured finish.

According to a second aspect of the present invention, there is provided a method of using a manually operable tool, as defined by said first aspect, for the purposes of filling or grouting. Preferably a load is applied to the handle for transmission through the work head onto the filling or grouting materials. The work head may also be configured to deform.

Preferably, the shape of the work head deforms while the head is dragged along a gap containing filling or grouting material.

According to a third aspect of the present invention, there is provided a method of manufacturing a manually operable tool, comprising a rigid CHU-PO4-Ga I- - I- 3 handle and a flexibly deformable work head attached to said handle, in which said work head provides a substantially continuous curvilinear work surface, wherein said handle and said work head are injection moulded together by a process of two-shot moulding.

The invention will now be described by way of example only, with reference to the accompanying drawings, in which:

Figure 1 shows a two-shot injection moulding machine having one injection moulding unit to produce a handle, and another injection moulding unit to produce a work head; Figure 2 (i) shows a moulding tool configured to produce a handle and a work head on the machine shown in Figure 1; Figure 2 (5) shows the moulding tool shown in Figure 2 (i) in an alternative configuration.

Figure 3 shows a handle and work head injection moulded in the moulding tool shown in Figure 2; Figure 4 shows the handle and work head shown in Figure 3 being used as a filling and grouting device; Figure 5(1) shows a close up of the work head shown in Figure 4; Figure 5(fi) shows an enlarged view of the work head shown in Figure 4; Figure 5(iii) shows a close up of the work head shown in Figure 4 in an alternative view; Figure 6 shows a close up of the work head in a further use of the filling and grouting device shown in Figure 4; Figure 7 shows a close up of the work head in a further use of the filling and grouting device shown in Figure 4; Figure 8 shows a second embodiment of a filling and grouting device; Figure 9 shows a third embodiment of a filling and grouting device; and CHU-PG4-GB 4 Figure 10 shows a fourth embodiment of a filling and grouting device.

An injection moulding machine 101 is shown in Figure 1, configured to operate a two-component injection moulding system, otherwise known as two-shot injection moulding. The machine 101 is provided with an injection unit 102 which works horizontally through the fixed mounting platten 103.

The machine 101 is further provided with another injection unit 104 which is located vertically above the mould area 105 in alignment with the position of a parting line on the mould. Injection unit 102 is loaded with granules of a thermoplastic elastomer material to produce the work head of a grouting and filling device, and injection unit 104 is loaded with granules of polypropylene to produce the handle of a filling and grouting device.

Figure 2(i) shows an injection moulding tool 201 configured to operate in the machine 101 shown in Figure 1. Injection moulding tool 201 is provided with at least two cavities 202 and 203 configured to produce a filling and grouting device. Preferably, cavity 202 is duplicated four times in moulding tool 201, and cavity 203 is likewise duplicated four times on said moulding tool. Tool 201 is mounted on a rotary platten 204. By injection with the vertical injection unit 104 shown in Figure 1, pre-moulded handles 205 are produced. At the same time the horizontal injection moulding unit 102 shown in Figure 1 injects the pre-moulded handles 206 of the previous operation cycle with the second component, the work head 207. When the mould 201 opens, the sprues 208 and 209 of both injection moulded parts are ejected along with the completed part 206. The pre-moulded handles 205 remain on the mould core.

In Figure 2(fl) the rotary platten 204 is swivelled by 180 degrees, thus causing the moulding tool 201 to rotate by the same extent. The pre moulded handles 205 are now in a finishing position; in the second set of cavities 202 the first parts, the handles, can be injected again. After a new ejection, the mould 201 turns, is re-closed and the new operation cycle CHW-P04-GI3, I- commences. One operation cycle takes approximately thirty seconds to complete.

Figure 3 shows the handle 205 moulded in combination with the work head 207, as shown in Figure 2(1) and 2(ii), to produce the finished filling and grouting device 206. The plan view shows a handle 205 moulded in polypropylene having a shape substantially similar to a paint brush handle. Such a shape, known as a beavertail, is known to have suitable properties of handling and ergonomics for a device used in decorating applications. Furthermore, it is envisaged that such a shape will render the device sufficiently similar in appearance to said paintbrushes as to greatly assist its visual integration into existing ranges of decorating products. The handle 205 is provided with a hole 301 for purposes of hanging for storage.

The polypropylene contains a blowing agent, whose function is to enable the moulding of the substantially thick sections of material necessary to confer the desired handling properties. The blowing agent is derived from talc and contributes to an overall stiffening of the handle 205.

Towards the end of the handle where the work head 207 is located is provided a spline 302 which extends two-thirds of the way into said work head. The spline can also be seen on the view in section. A purpose of the spline is to provide means for transmitting the compression exerted by a hand grip through handle 205 into the flexible work head 207, so that the work head is squashed down and around a gap to be filled and the surfaces immediately adjacent to said gap. A further purpose of the spline 302 is to provide an increased area of contact between the surfaces of the polypropylene in the handle 205 and the thermoplastic elastomer in the work head 207, in order to optimise the bonding between the two elements.

The choice of a thermoplastic eiastomer for the work head is explained by a combination of properties in this material suitable for the present application. Thermoplastic elastomers have the appearance and CHU-PO4-GI3.

/I- 6 mechanical properties of rubbers, together with the processing characteristics of thermoplastics.

Preferably, the thermplastic elastomer used to manufacture the work head 207 is proprietary product 'Evoprene G 936' supplied by Laporte Alpha-Gary Limited. This material is highly flexible, having a hardness of only 10 Shore A. It will therefore compress extremely readily and spread evenly over a gap to be filled without the need for excessive force being applie o the handle 205. 'Evoprene G 936' is based on Shell Chemicals 11 0 Kratow G SEBS' (styrene-ethylene-butylene-styrene) block copolymer. This material is olefin-based, like polypropyiene, which results in a strong bond at the polymer level between the two materials when moulded in combination (as Figures 1 and 2). The work head 207 will therefore resist any shear or peel forces at the bonding faces with the handle 205 and the spline 302. Such forces might otherwise cause the two elements to separate under working loads, thus allowing dirt and moisture into the resulting gaps and compromising the overall functionality of the device.

The shape of the work head 207 is substantially similar to that of a human fingertip. Such a shape is defined by a plurality of curves which create a substantially convex, smooth and irregular surface 303. This shape has been found to work effectively in the wide variety of applications where the filling and grouting device is used.

Figure 4 shows a filling and grouting device being used for a home improvement task. In this application, the operator has introduced a run of filling material 401 between a bath and an adjacent wall, upon which is a plurality of tiles 403. The operator grips the handle 205 of a filling and grouting device and applies downward pressure on the filler 401 in the direction of arrow 404, whilst at the same time pulling the device in the direction of arrow 405.

Figure 5(1) illustrates a close-up sectional view of the work head 207 of the filling and grouting device shown in Figure 4. An effect of the CHULP04-GB.

X 7 application of work head 207 simultaneously in the direction of arrows 404 and 405 is the compression and smoothing down of filler 401 to produce the desired finish 501.

It is known that materials including the filler 401 are substantially particles based in a solution of water. Such materials produce an abrasive action upon a work head 207 of a filling and grouting device, which can lead to wear of said work head. In order to reduce this effect, a quantity of an ingredient known as a slip agent is added to the thermoplastic elastomer used to make the work head.

Slip agents are usually added to thermoplastic materials to assist with de-moulding problems in the injection moulding cycle of the kind illustrated in Figures 1 and 2, wherein the slip agent can cause a moulding to be more easily removed from the moulding tool. In the present application, a slip agent is added to the material used to mould the work head 207 to render its surface 303 slippery. This property enables the work head to be drawn over filler and adjacent surfaces more easily and causing less wear on said work head. Preferably, said thermoplastic elastomer is 'Evoprene G 936' and said slip agent is 1 % crodamide. Said slip agent is a wax-based material and its most familiar application is to be found in lipsticks and cosmetics. The advantage in the present application is that the wax repels water. Because said filling materials are substantially waterbased, the respective surfaces of said filler 503 and the work head 303 tend to repel each other. An effect of this is to reduce wear on the working surface 303 of work head 207. A further effect is that finished filler surface 501 is substantially smooth and even.

In a preferred embodiment, the working surface 303 of work head 207 is provided with a fine texture, as shown in Figure 5(ii). In this view a magnified section of working surface 303 is shown, wherein an arrangement of peaks 504 and troughs 505 in said texture can be seen. When the filling and grouting device is dragged across the filler 401, CHULP04-GI3- I- 8 particles of said filler mixed with water are collected in said troughs 505. This creates a further barrier between the work head 207 and the filler 401 which functions as a bearing between the two respective surfaces. An effect of this is that wear on the work head 207 is further reduced. Preferably, said texture is fine and is expressed as 27-33 VD1.

Figure 5(iii) illustrates the work head 207 shown in Figure 5(1) from a different angle. The operation shown in Figure 5(i) comprises the application and smoothing of filler in a position between a bath edge 402 and the adjacent wall 403, which is also illustrated in Figure 4. The profile of the join is substantially right angular and having a blend radius at its inner corner. Upon application of the filling and grouting device, the surface 303 of the work head 207 assumes a substantially right angular profile, due to the flexibility of said work head. The surface of the filler 503 is thus also provided with said substantially right-angular profile. Such a result is made possible because the work tip is flexible not only in one plane, but in any number of planes, and all at the same time.

Figure 6 shows the filling and grouting device being used a finish a gap in which the adjacent surfaces 601 are aligned with one another. Upon application of the filling and grouting device, the surface 303 of the work head 207 assumes a substantially level profile, due to the flexibility of said work head. The surface of the filler 602 is thus also provided with said substantially level profile.

Figure 7 shows the filling and grouting device being used to finish a gap in which the adjacent surfaces 701 are irregular and unevenly disposed. Upon application of the filling and grouting device, the surface 303 of the work head 207 assumes a substantially irregular profile, due to the flexibility of said work head. The surface of the filler 702 is thus also provided with said substantially irregular profile.

Figure 8 shows an second embodiment of the present invention. The second embodiment of the filling and grouting device has a handle 801 and CHU-P04-GB- 9 a work head 802. The handle is provided with a spline 803 whose position when viewed in sectional side elevation is in the centre of the work head 802. The spline 803 is further provided with a hole 804 which confers additional mechanical locking properties on a bond between said handle 801 and said work head 802, wherein said work head is manufactured from either a thermoplastic elastomer or a self-skinning flexible polyurethane foam.

Figure 9 shows a third embodiment of the present invention. The third embodiment of the filling and grouting device has a handle 901 and a work head 902. Bonding means are provided by a metal ferrule 903, wherein said ferrule is wrapped and pinned around the joint between the handle and the work head. Said work head is manufactured from either a thermoplastic elastomer, a self-skinning flexible polyurethane foam, a natural rubber or a silicon rubber. Said ferrule is substantially similar to the means used for bonding paintbrush bristles to their handles. Said handle is manufactured from polypropylene, polyethylene or similar plastics material, or from wood.

Figure 10 shows a fourth embodiment of the present invention. The fourth embodiment of the filling and grouting device has a handle 1001 and a work head 1002. The handle is provided with a spline 1003 whose position when viewed in sectional side elevation is near the centre of the work head 1002. The work head 1002 is manufactured from a natural rubber or silicon rubber and is provided with a cavity 1004 inside. The work head is fixed to the handle 1001 by pushing onto the spline 1003. Said spline is provided with a locking rim 1005 which engages with a groove 1006 on the inner surface of the work head. The cavity 1004 is substantially larger than the spline 1003 which fits inside it. After assembly therefore, a void 1007 is created. Said void 1007 is defined as a deflection chamber; when the filling and grouting tool is used as shown in Figures 4 to 7 the work head partially collapses under compression into said deflection CHU-PO4-W chamber. This enables the surface of the work head 1008 to assume the profile of the surfaces adjacent to the filler so as to produce a smooth and even finish on said filler.

The work head 1002 may be pulled off the spline 1003 and replaced when required, for example when said work head is worn out. Because in this embodiment the handle and work head are manufactured separately, the handle may be readily recycled, wherein said handle is manufactured from polypropylene, polyethylene or other suitable material.

1 CHU-P04-Ga 11

Claims

1. A manually operable tool, comprising a rigid handle and a flexibly deformable work head attached to said handle, wherein said work head provides a substantially continuous curvilinear work surface.

2. A tool according to claim 1, wherein a flexibly rigid spline extends from said handle and said work head is bonded to said. spline.

1

3. A tool according to claim 1 or claim 2, wherein said handle is substantially similar to a paintbrush handle.

4. A tool according to claims 1 to 3, wherein said curvilinear work head is convex in shape and has a profile substantially similar to a human fingertip.

5. A tool according to any of claims 1 to 4, wherein said work head is a thermoplastic elastomer material.

6. A tool according to claim 5, wherein said thermoplastic elastomer material is Evoprene G 936.

7. A tool according to any of claims 1 to 6, wherein said curvilinear work surface has a fine textured finish.

8. A method of using a manually operable tool according to any of claims 1 to 7 for the purposes of filling or grouting.

CHU-PO4-GS- 12

9. A method according to claim 8, wherein a load is applied to said handle for transmission through said work head onto said filling or grouting materials.

10. A method according to claim 9, wherein said work head is configured to deform.

11. A method according to claim 10, wherein the shape of said work head deforms while said head is dragged along a gap containing filling or grouting material.

12. A method of manufacturing a manually operable tool, comprising a rigid handle and a flexibly deformable work head attached to said handle, in which said work head provides a substantially continuous curvilinear work surface, wherein said handle and said work head are injection moulded together by a process of two-shot moulding.