AU2762600A - Method and apparatus for treating fluent material - Google Patents

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT: METHOD AND APPARATUS FOR TREATING FLUENT MATERIAL THE FOLLOWING STATEMENT IS A FULL DESCRIPTION OF THIS INVENTION, INCLUDING THE BEST METHOD OF PERFORMING IT KNOWN TO ME:ooo" The invention relates to a method and apparatus for treating fluent material, in .".particular plaster, stucco or cement in a fluent state. The invention also includes a °portable power unit which can be used to power the apparatus and an apparatus to mix .i and to pump the fluent material in its fluent state.

Throughout the specification the term "fluent" is to be understood to mean capable of flowing either under gravity or under pressure at a rate dependant on the physical •characteristics of the material.

.o 10 The present invention will be described with particular reference to the treatment of cement render and its application on walls although the invention equally applies to the handling and application of plaster whether to walls or ceilings, floors, or other surfaces. The handling, and, in particular, the application to a surface, of glue is also contemplated as within the scope of the invention. The invention also relates to the description of a portable power unit which is hydraulic which can be used with a hand unit having interchangeable elements to apply and treat a surface with the fluent material and which can be used to power other tools such as drills, cutters or the like.

Previously, the application of cement render has been a labor intensive exercise where the cement is prepared at one location transferred by a wheelbarrow to the work site and there applied to the wall again using a manual technique followed by the use of manual tools to spread and smooth the material on the wall. This prior art technique is labor intensive and relatively slow.

The present invention seeks to overcome these disadvantages in the prior art by providing an integrated solution to the problem of preparing and delivering the fluent material, for example cement or plaster, to a work site in a more continuous and reliable fashion while providing means for applying the fluent material to the surface with minimal manual effort on the part of the workmen, or alternatively, the invention seeks to provide an alternative to the existing techniques and apparatus.

According to a first aspect of the invention there is provided a hand held device for ••applying fluent material to a surface including a stationary housing, a motor attached to said housing for driving a rotatable attachment, said rotatable attachment having a shaft driven by said motor, a handle fixed to said housing for guidance, means for supplying power to said motor, and means for supplying fluent material to said rotatable attachment, said rotatable attachment having means for applying said fluent material to a surface as said rotatable attachment rotates. Preferably, the motor is powered hydraulically and is controlled by a fluid switch or valve and said shaft is *•go accommodated in a bush of said stationary housing.

According to a second aspect of the invention there is provided a portable power unit for powering a remote device, the portable power unit including a fluidic power source, a fluidic reservoir for supplying the fluidic power source with fluid including an outlet from the reservoir and a fluid return means for returning fluid to the reservoir, means for supplying a moisturising agent from a moisturising agent reservoir and electric power supply means, including switch means, for powering said fluidic power source and said moisturising agent supplying means, said portable power unit having at least one fluidic power outlet and at least one moisturising agent outlet for supply of said fluid and said moisturising agent respectively to a remote location. Preferably, the at least one fluidic power outlet and the at least one moisturising agent outlet are directly connected to a remote hand held device where the fluidic source operates a fluidic motor to produce for example rotational motion of at least a portion of said hand held device, while said moisturising agent source is applied to a surface being treated through an outlet on the hand held device.

Preferably, the portable power unit is an hydraulic power unit and said moisturising agent means is a pressurised water supply for spraying onto the fluent material, for example, cement render or plaster as the fluent material is applied to, or treated after being applied to, a wall or other surface.

According to a third aspect of the invention there is provided a hand held device for applying fluent material to or working fluent material on a surface including a 10 housing, a motor attached to said housing for driving a detachable head portion, a hub .driven by said motor to which said detachable head portion is attached, a handle for holding said device for guidance, means for supplying power to said motor, and means for supplying a moisturising agent to the region of said detachable head portion. In some forms of the invention the means for spraying a moisturising agent may be omitted. Preferably, the motor is an hydraulic motor and the moisturising agent supply is a pressurised water piping extending to near the rim of said detachable head portion.

The hand held device has interchangeable attachments, (detachable head portions) for 20 spraying the wall with a first bonding layer, or for applying the fluent material, for S" example, cement render or plaster to the surface or for spreading and smoothing the fluent material, for example cement render or plaster once on the surface.

According to a fourth aspect of the invention there is provided a portable apparatus including a portable power unit as stated above and a hand held device as stated above wherein said means for supplying power to said motor of said hand held device includes conduit means connected from said hand held device to said fluidic power outlet of said portable power unit and said means for supplying a moisturising agent to the region of said detachable head portion includes conduit means connected from said hand held device to said moisturising agent outlet.

According to a further aspect of the invention there is provided an apparatus for mixing and pumping fluent material to a remote location, said location including a hand held device or a work site for use of the fluent material, said apparatus including mixing means for mixing dry and wet ingredients together on demand to form a fluent material, means to deliver said fluent material to pumping means for pumping said fluent material, said pumping means including first means for maintaining said fluent material in motion whether said fluent material is or is not on demand and second means, connecting to said first means, for pumping said fluent material through an outlet when a demand for said fluent material is made; power means for supplying 10 power to said mixing means and to said pumping means; and controlling means for controlling said power means to supply power selectively to said mixing means and to said first means and/or said second means of said pumping means as a function of at Sleast said demand.

S 15 The fluidic power unit may supply power sufficient to run one or many hand held devices whereby several hand held devices may be connected in parallel to the power unit using valve means to allow connection or disconnection for this purpose without o •o loss of pressurised fluid or moisturising agent.

20 While the fluidic power unit to be described with respect to the preferred S -embodiments is an hydraulic unit, a pneumatic unit is also contemplated. The fluidic power unit can be a separate portable unit according to the invention and the unit can also be used to power other fluidically powered tools such as concrete or cement drills, cutters or abrasive tools where the moisturising agent outlet of the unit can be used to provide wetting of the workpiece or the tool to cool and/or lubricate them while the tool is working. The moisturising agent can in this case be water, oil or a mixture of water and oil.

According to yet another aspect of the invention there is provided a method for treating fluent material including the steps of: mixing dry ingredients in given proportions, adding a wetting and/or setting agent to form a material in a fluent state, pumping said fluent material to a remote location, spreading said fluent material using a hand held unit having a plurality of detachable head elements at said remote location and smoothing said material after spreading using at least one other detachable head element with said hand held unit.

Preferred embodiments of the invention will now be described with respect to the drawings in which: Figure 1 shows schematically a first form of hand held device according to the invention; Figures 2, 2a, 2b show schematically a second form of hand held device according to the invention; -Figures 3, 3a show schematically a third form of hand held device according to the invention; Figure 4 shows schematically a fourth form of hand held device according to the invention; Figure 5 shows schematically an apparatus according to another aspect of the invention for mixing and delivering the fluent material to a hand held device or work site; Figure 6 shows schematically another aspect of the invention being apparatus for use with the apparatus of Figure 20 Figure 7 shows schematically a portable fluidic power unit according to the o invention; and Figures 8-11 show schematically a further form of a hand held device according to the invention.

Figures 1-4 show various forms of devices for use with the hand held unit according to the invention. The basic unit is (as shown in figure 1) made up of a central longitudinal housing 10 which houses an hydraulic motor 12 supplied with hydraulic fluid under pressure through the hydraulic line 14 which is connected either directly or via a distribution panel to an hydraulic power unit to be described below. The hydraulic motor 12 rotates the hub 16 about the axis 18. To the hub 16 is removably attached a circular plate 20 to which in this unit is fixed an attachment 22 made of a foam or sponge like material. For "floating" a plastic or wooden or MDF material can be used for the attachment. The foam material 22 is detachably fixed to the plate for example by a number of velcro (registered tm) strips (not shown). The plate 20 is attached to the hub 16 by screws 21 or other removable fasteners.

The foam or sponge like material 22 may be of a right circular cylindrical shape, as shown, or may be of a truncated conical shape having a wider diameter away from the plate 20. The latter shape allows easier working at or adjacent to corners due to the chamfered edge.

10 To aid centring of the foam attachment 22 on the plate 20, the plate 20 may include radially extending flanges (for example, four spokes set at right angles to one another). The foam attachment 22 in this case would have corresponding slots or apertures, the foam then fits over the flanges to thereby locate the attachment 22 with respect thereto. The foam attachment 22 is then attached by velcro fasteners to the 15 plate A handle 24 extends from one side of housing 10 to the other in a preferably circular path. Two arcuate arms extend from the housing 10 to the circular handle 24 to allow the unit to be gripped by either hand of a user and for accommodating left or right 20 handed users. Either handle is made in an arc for this purpose. A supply of water S •under pressure is supplied via tubing 30 which extends through the flexible connector 32 and the housing 10 and exits from the housing 10 by way of the tubing 34 at jet orifice 36. The tubing 34 is partly supported by the handle 24 and provides ajet of water from the orifice 36 to assist in treating the material which has already been applied to the wall for example by a hand held device which will be described below with respect to figure 2 or 3.

Referring to figure 2, the hand held device in this drawing is for applying stucco or plaster to the wall. In this version the plate and foam covering 20, 22 are removed and replaced by plate 46. Plate 46 includes toothed wheel 40 co-axial with the hydraulic motor 12 of housing 10 and driving, by means of a chain or belt drive 42, the toothed wheel 44 attached to the centre of cover plate 46. The toothed wheel 44 rotates the shaft 48 and hence the cover plate 46 about the axis of shaft 48. The rate of rotation of the cover plate 46 will depend upon the type of fluent material which is being used.

Fluent material is supplied to the housing 50 through the supply line 52 (shown in the broken lines). The cover plate 46 may have 2,4,6,8 or other number of fluent material outlets 53 and associated blades 58 (as best shown in figure 2a) attached to the plate 46. In the embodiment shown in figure 2, the plate 46 has 4 blades 58 each with outlets 53 (although only three connections are shown in fig 2 and only one blade 58 is shown in fig 2a for simplicity) each supplied by its respective pipe 54 from the central housing 50. Each pipe 54 extends through a hole 56 in the cover plate 46 to 10 the rear of the blade 58 (see fig 2a). A flexible coupling is used. The fluent material enters the housing 50 via the supply pipe 52 and is distributed through each of the lines to the rear of the blade. The outlet 53 in the blade 58 allows the fluent material 59 to flow out whereby with the rotational motion of the cover plate 46 about the shaft 48 the fluent material 59 is spread against the surface 60. The blade 58 is made of a flexible construction and is preferably arranged at an angle of between 250 and 450 to S the plate 46. The blade 58 is fixed securely to the plate 46 at one end 62 with the rest of the blade trailing and flexible enough to allow a sealing of the blade 58 to the surface. The elements of the hand held unit are otherwise the same as shown in figure 9 I1 namely the housing 10, the hydraulic motor 12 the connector 32 and the inlets and 14 for respectively water and hydraulic fluid.

Fig 2(b) shows in schematic form how the shaft 48 rotates while the housing remains stationary. The fluent material 59 enters the cavity 67 via conduit 52 and enters the hollow bore of shaft 48 through openings 69 therein as the shaft rotates as indicated by arrow 71. The shaft 48 is sealed to the housing 50 by O-rings 70. The fluent material 59 then exits from shaft 48 to flow into the respective conduits 54 as described above through a mainfold (not shown).

Normally when spreading the fluent material a spray of water from jet orifice 36 is used as it is generally necessary to keep the render or the stucco plaster moist. The spray from the water jet 36 is normally applicable to each of the attachments which will be described with respect to figures 1-4. In any instance where this is not the case a cover may be attached to the outlet or a switch may be supplied in the hand held unit for turning off the water supply in that unit.

The toothed wheels 40 and 44 and the chain drive 42 provide for a speed reduction of the cover plate 46 and thus of the blades 58 in this embodiment.

The exit orifice 53 for the fluent material 59 is chosen to allow an even distribution of the fluent material 59 about the area of the cover plate 46. For example, in a four bladed arrangement such as shown in figure 2 the exit orifices 53 in each blade may 0 be arranged at increasingly greater or lesser radial distances from the centre of the cover plate 46 in each blade successively as one moves in the direction of rotation of the cover plate 46. Other arrangements are also contemplated.

Referring to figures 3 and 3a, a third embodiment for the hand held device is shown.

In this embodiment attached to the hub 16 is a housing 80. The housing 80 includes a base plate 82 enclosed by a cylindrical box 84 which is stationary and spaced from the base plate 82 and sealed with respect thereto by a flexible sealing member 86. The box 84 is fixed to the housing 10. Attached to the base plate 82, for example by ooo* welding or by being molded in situ, are a pair of blades 88, 90. The blades 88, 90 as best shown in figure 3a are made in two segments 92, 94 to provide a scooping action on material which is placed into the housing 80 via the piping 96. This material may be deposited in a single spot or in a line so that the action of the blades or sweeper arms 88, 90 acts to gather up the material and to move it along the blades or arms 88, towards the outer perimeter where as the base plate 82 rotates, the material is forced to exit through the aperture 100 provided in the housing 80. For example, cement supplied by piping 96 can be flung onto the walls using this hand held device..

The rotation of the plate 82 is such as to provide for an upward directed path for the fluent material (cement) as it leaves the aperture 100.

A second form of hand held device is shown in figures 8-11. The device (see Fig. 8) includes an upper housing 500 which is fitted over detachable rotary section 520, as shown in figure 9.

As shown separately in figure 10 the upper housing 500 has a circular plate 502 with a central bush 504 which accommodates the hollow drive shaft 522 of the rotary component 520.

A handle 506 is fixed to the plate 502 by a support forming a pair of wing shaped braces 508, 509 welded along the edge 510. The handle 506 has a pair ofarcuate hands 512, 514 curving about the sides of the plate 502. To each hand is affixed respective gripping portions 516, 518 which meet at apex 519. The handle 506 is 10 further supported on the plate 502 by being braced to the central bush 504 by arms 505, 507. Braces 508, 509 and bracing arms 505, 507 are formed with apertures 511 to reduce weight. Buttons or switches 513 are provided on each brace 508, 509 to regulate the flow of fluent material to the rotary section 520 of the device.

Referring to Figure 9, the rotary section 520 comprises a hollow drive shaft 522 S.having an entry aperture (not shown) for feeding fluent material to the interior of the drive shaft and thence to blades 530. Fittings (not shown) on the upper housing 500 deliver fluent material, i.e. plaster to the drive shaft through a rotary mechanism such as described above with respect to Fig. 2b. Bearings support the hollow drive spindle 522 for rotation about its axis.

The blades 530 are fixed to respective arms 532 which are arranged in a twisted cruciform pattern about the central hollow drive shaft 522. Each arm 532 is formed as an L-shaped element with a short base 533 extending radially from the hollow shaft 522 and joined at a right angle to a longer distributor tube 535 to which the blade 530 is attached. Four such arms arranged at 900 intervals about the shaft form the twisted cross arrangement. An alternative form (not shown) provides each of the 4 arms as a tube extending radially from the shaft to form an X-shaped array. However it is considered that the twisted cruciform arrangement provides for a better distribution of the fluent material. The fluent material, for example plaster, enters through the aperture in the hollow drive shaft 522 flowing down the hollow central bore of the shaft 522, enters each of the hollow arms 532 and flows therealong to the orifice 534 in each arm 532. As shown each aperture 534 is located at a different distance from the shaft 522 in order to better distribute the fluent material throughout the footprint of the device. Each blade 530 is set at an angle to aid the distribution of the fluent material as the rotary section 520 rotates.

Detail at the aperture 534 of the blades 530 is shown in Figure 11 which shows a cross section at that region. Each blade 530 includes a front spreader portion 550 joined to a fixing portion 554. The blade 530 is set at preferably 200 to the horizontal. This angle may be between 20-600. The spreader portion 550 has an aperture 552 therein 10 through which the plaster (or other fluent material) exits. The fixing portion 554 is fixed to the hollow arm 532 by a screw 554 tapping into lug 533 fitted inside the hollow arm 532 which may be flattened for better securement in the area of the fixture. A rear housing 558 acts as a manifold for each blade 530 to join the exit "i orifice 534 in the arm 32 to the discharge aperture 552. The path of the fluent material is shown by arrow 553. A resilient gasket 557 is fitted between rear housing 558 and the spreader portion 550 to provide a flexible seal for the action of the blade 530 when the device is pressed against the surface 560. When the device is not in contact with •surface 560 the blade rests at an angle determined by the angle of the fixing portion 554. When the blade 530 is pressed against the surface the blade which is resilient, for example being made of spring steel, in combination with the resilience of the gasket allows the spreader portion 550 to bend and adjust to an angle of approximately 5-100 with respect to the surface 560 as shown in Fig. 11. This provides a sealing action of the blade 530 against the surface 560 and a smoothing action on the fluent material as the blade 530 rotates.

An annular plate 526 supports the arms 532. A further set of four blades 531 is provided on the annular plate 526 arranged at approximately 900 with respect to each other and approximately 450 with respect to the adjacent spreading blade 530 of the twisted cruciform array (or the alternate X-shaped array). Each of the blades 531 extends at an angle of substantially 100 with respect to the horizontal and trails a spreading blade 530 thereby aiding smoothing of the material being spread from the blade 530 especially at the periphery. It is considered that the twisted cruciform array 11 is better suited to provide a smooth spreading of plaster particularly in the centre of the device, an X-shaped array tending to form a crease or ridge in that region. The annular plate 526 is fixed to each of the arms 532 by fixtures 527. This enables replacement, repair or cleaning of the arms as required. Other numbers of radial arms 532, for example 2, 6, 8 are also contemplated.

The rotary section 520 is driven by the hydraulic motor 540 via a toothed belt drive 542 engaging the toothed gear wheel 544. A smaller diameter toothed wheel 546 is driven by the hydraulic motor 540 to produce a speed reduction between the hydraulic 10 motor 540 and the hollow drive shaft 522.

*6oS oe Before applying cement render to a wall, the wall is normally treated with a coating to *5pe .oaid retention of the cement once applied, that is, the adhesion of the cement render to the wall. An attachment for this purpose for the hand held device of figure 1 is shown 15 schematically in figure 4. A housing 110 similar to that as shown with respect to S..o figure 3 but of a more elongate form accommodates a pair of interdigitated turbines too.

112, 114. Each turbine 112, 114 may be a wheel made up of comb-like spokes, each o lturbine having teeth of differing separation. Alternatively, each turbine 112, 114 may be composed of spoked wheels separated apart by spacers of the desired thickness.

The lower and slower turbine 112 is immersed in a bath 115 of the material 117 which *gS° is to be distributed through the orifice 116 of the housing 110. This material is in a more fluid state than either cement render or plaster. The upper turbine 114 turns at a greater RPM its blades 120 interdigitating with the blades 122 of the turbine 112.

Material transported from the bath 115 is delivered to the turbine 114 and is flung from turbine 114 through the aperture 116 by centrifugal action. As the turbine 114, turning in the direction shown by arrow 130, progresses towards the aperture 116, material is flung against the inner wall of the housing 110 reducing the quantity of material 117 which can exit through the aperture 116. To increase that quantity, the housingl 10 is shaped, for example by cavities 132, 134 so that material flung from the turbine 114 is returned to the turbine 114 further along in its path as it advances towards the aperture 116. In this way some of the material flung from the turbine 114 12 is redistributed and returned to the blades 120 of turbine 114 to be available for spraying through the aperture 116.

Referring now to figure 5, apparatus is described for mixing and transferring the fluent material to the location where the material is to be used. The material may be used in the usual manner or by a hand held device as described above. The hand held device shown with respect to figure 3 can be used with regard to the application of cement render to a surface.

Cement render can be supplied to the location by a mixer and pump which will now be described with respect to figure 5. The output from such a device is then supplied to the hand held device via the piping 96 of the device of figure 3, or alternatively may be supplied to another apparatus at the location, which will be described with respect o• to figure 6, for manual application of the fluent material to the surface being treated.

The apparatus is made in ;wo stages the first stage is the mixing section 200 and the S .second stage is the pumping section 202. In the mixing section 200 hoppers 206, 208 (only two are shown but more may be used) are fed with the dry material to be mixed, for example sand and cement, and/or lime. The hoppers 206, 208 are vibrated by the motor 210 to facilitate the discharge of the material from the hoppers 206, 208 into their respective metering screws. Only one of these screws is shown as integer 212 for simplicity. Each metering screw is driven by a wheel (toothed, gear or pulley) 214, 216. A motor 213 drives a series of wheels including the wheels 214, 216 which drive their respective metering screws 212. A water pump 218 can also be driven from the same drive.

The metering screws 212 are sized and rotated so as to provide the required measured quantity of sand or cement or lime as required into the chute 222. The hoppers 206, 208 are sized to accommodate a given quantity of dry materials. In addition, the metering screws 212 can be replaced by other metering screws or the speed of the screws can be varied by varying the size of the wheels 214;,216 to provide a given ratio of materials. The ratio of sand to cement and/or lime can be varied depending 13 upon the mixture required for the particular application. Therefore the instant invention can be used to prepare these separate mixtures by making these alterations.

The dry ingredients progress along their respective screws to exit therefrom and to fall down the chute 222 into the inclined rotary mixer 224. Water is sprayed via pipe 226 at a rate provided by the water pump 218. The ingredients tumble along the longitudinal axis of the mixer 224. Projections or teeth 228 on the inside of the mixer 224 aid in the mixing and tumbling action of the wet and dry ingredients as the motor 230 rotates the mixer 224. The length of the mixer 224, its angle of inclination and the rate of turning of the mixer 224 provided by the motor 230 are regulated to provide the required mixing of the wet and dry ingredients.

a The mixture of wet and dry materials form a fluent material and exit from the mixer 224 through the end 232 and into the pumping section 202 through the opening 240.

The pumping section 202 in turn is made into sections 242, 244. The first section 242 is of a larger diameter than the following section 244 and is connected thereto by a conical tapered section 246 to provide adequate pressure differential between the two sections 242, 244. The first section 242 is a priming section of the pump 202 and the screw 262 therein is kept rotating even when there is no current demand for the fluent material. At this time in the absence of demand for fluent material the screw 273 in •"the section 244 is kept stationary. In order to do this the sections 242 and 244 are driven by separate motors 248 and 250 respectively driving co-axial shafts 252 and 254 via respective belt or chain drives. The co-axial shafts 252, 254 are able to rotate freely with respect to one another, for example by using an insert between the shafts made of a bronze material and greased. The turns 260 of the pump priming screw 262 are arranged at a given separation and inclination to advance the material from the mixer 224 along the longitudinal axis of the shaft 252 towards the truncated conical joining section 246.

Holes 264 are provided in the turns 260 of the screw 262. The holes 264 allow the material to flow back along the priming section 242. As the material is added from the mixer 224 through the opening 240 the mixed material accumulates at the waisted joining section 246 where a sensor 270 is located for sensing the pressure of the mixing material at that point. Once a set pressure has been reached the sensor 270 switches off the supply of power to the screw motor 213 and the vibratory motor 210 stopping addition of the dry ingredients to the mixer 224. As stated, the screw 262 of the priming section 242 continues to rotate maintaining the ingredients moving and mixed together. At that time the first turn of the screw 273 in the pumping section 244 is stationery and acts as a barrier preventing advance of the fluent material into the forward or pumping section 244. When the fluent material is required, the shaft 254 is rotated by applying power to the motor 250. The turns 272 of the screw 273 are arranged at a lesser angle and are more closely spaced than the turns 260 of the screw 262 of the priming section 242. As the shaft 254 rotates the fluent material S• from the priming section 242 advances along the pumping section 244 into the waisted joining section 280 to then exit from the outlet 282. The outlet 282 has a pipe S'.i 15 (not shown) connecting the outlet 282 to the remote location or point at which it is to be used, for example connecting the pump section 202 to a hand held device as shown with respect to figure 3 or to the table as shown with respect to figure 6.

When there has been no demand for a given time 2 minutes) the priming section 20 and hence shaft 262 may be stopped and then re-started after a further delay minutes) or upon demand. This better maintains the quality of the material.

eeol In another enhancement, the section 242 of the mixer 202 near the opening 240 may include a number of turns 260 of the screw 262 with blades which provide both a mixing and an advancing or pumping action. This aids in addition to the action of the slots 264 the creation of a uniform mixture even when the pump is not discharging material.

As material advances from the priming section 242 into the pumping section 244 the pressure measured by the sensor 270 decreases whereby the switch 271 closes resupplying power to the motors 210 and 220. Once again dry ingredients are added to the screws such as 212 providing more material to the mixer 224 via the chute 222.

The motors 210 2'20, 230, 248. and 250 may be electrical motors or alternatively may be hydraulic motors driven from the fluidic power unit which will be described with respect to figure 7. The power unit may be co-located with or remote from the mixing and pumping unit as desired.

Further control of the motion of the pumping section 244 may be provided at the remote location to which the fluent material is delivered via the outlet 282 with switches to control the on or off status of the motor 250 allowing the fluent material to be delivered as required to the remote location.

It is also contemplated that the apparatus of figure 5 can be used with suitable alterations for mixing and pumping concrete. The apparatus could be located on a truck to be powered locally and moved from site to site.

Referring to figure 6, rather than the fluent material flowing to the hand held device the fluent material may also be deposited on a table 290 to be picked up manually and .o employed in the usual manner by workmen rendering a wall with cement. A flexible hose 292 connects to the pumping outlet 282 of the apparatus shown with respect to figure 5 and fluent material (for example, cement) 296 flows out of the orifice 294 in the table 290 for use by the workmen. The fluent material 296 on the table 290, or on i"•'"the surface being treated, can be kept wet by a moistening agent (for example, water) sprayed from hose 293 which can be controlled with valve 291. The moisturising agent may be supplied from the portable power unit which will be described below with respect to fig.7. When sufficient fluent material 296 (cement, plaster) has been delivered to the table 290 the workman can stop the flow by crimping or closing the hose 292 by activating a switch 298 on or near the table 290. The switch 298 may be a manually, hydraulically, pneumatically or electrically operated device where, for example, a plunger 297 having a particularly shaped head 295. (for example, hemispherical) presses the hose 292 into a cavity 299 of complimentary shape to shut off the hose 292. A similar switch may be applied at the hand held device for example as shown with respect to figure 2 or figure 3.

16 The mixing and pumping sections of the apparatus are made of sufficient size to provide the supply of the material in the required quantity as well as allowing the machine to be readily moveable from site to site within a building, namely of sufficient width and height to be accommodated through a doorway. The mechanism, for example as shown in figure 5, can be provided within a housing which is supported with a wheeled under carriage and the housing may be pushed about the building site by a handle affixed to the housing.

The fluidic power unit is shown schematically in figure 7. Inside a housing 300 an electric power supply 310 provides power to an electric motor 320. This motor 320 may be a DC electric motor supplied through a transformer or may be an AC unit such as used in various domestic appliances. The electric motor 320 either directly or °oo• through appropriate gearing drives an hydraulic pump 330 which pressurises an 15 hydraulic fluid which is to be used to drive the hand held device of figs 1-4 or the mixing and pumping unit of figure 5. The hydraulic pump 330 is provided with a "reservoir 340 from which the hydraulic fluid is withdrawn and to which excess hydraulic fluid is returned via the return valve 350. In addition, a water reservoir 360 is provided which feeds a water pump 370 which pressurises the water to approximately 4 Bar to be used to spray from the hand helddevice as described above with respect to figures 1-4. An electrically or hydraulically driven unit can be provided for this purpose. Switches 380 on the power unit or at the hand held device (not shown) or mixer-pump can be used to turn the power supply on or off as the requirement arises. Where more than one device is operated by a single power unit provision can be made so that the respective device can be operated by the single power unit independently of any other device. For example, a hand held device can stop working while the mixer and priming portions of the mixer-pumping device continues to work. The housing 300 may accommodate meters for measuring the hydraulic fluid pressure (385), the quantity (390) of hydraulic fluid remaining in the tank 340 as well as the water pressure (395) and the water quantity (400) in the water tank 360 as well as metering other quantities (410) such as the power consumption, voltage or current of the electric motor(s) 320, 370 used. Indicators 412, 414, 416 show respectively the operating status of the hydraulic, water and power supply of the unit.

The electric motor(s) is(are) cooled by a cooling fan 420 and preferably also by an upward draft of air in part driven by the thermal current generated by the heat from the motor(s). The apparatus, as shown in figure7, can be provided with a wheeled under carriage 440 and may be pushed about the building site by handles 430 affixed to the housing 300.

One pressurised hydraulic fluid outlet 450 and return 460 for the power unit is shown, although it is contemplated that several such outlets may be provided to operate a number of devices. Equally a single pressurised water outlet 470 is shown but a number may be provided. The water tank 360 may be topped up through inlet 480.

Similarly an inlet is provided to fill the hydraulic fluid tank 340.

o• Most hand tools are of an electrically powered variety. By providing hand tools with an hydraulic motor the present invention provides for a more efficient, versatile lighter •and quieter unit at the work surface. For example, the noise of the electric motor, which is often a distracting factor in hand tools or the risk of electrocution (especially in the present environment where a water spray is used) can be reduced in the instant invention respectively by adequate sound insulation in the housing or isolation and •insulation of the electrical power supply at the remote unit.

Although the invention has been described above with respect to several embodiments thereof variations are possible within the knowledge of a person skilled in the art. For example, a pneumatic power supply may be used in place of the hydraulic power unit described above. When, for example, the unit described above with respect to Figure is mounted on a truck, the power supply therefor may be hydraulic with power taken from the motor of the truck

Claims (20)

1. A hand held device for applying fluent material to a surface including a stationary housing, a motor attached to said housing for driving a rotatable attachment, said rotatable attachment having a shaft driven by said motor, a handle fixed to said housing for guidance, means for supplying power to said motor, and means for supplying fluent material to said rotatable attachment, said rotatable attachment having means for applying said fluent material to a surface as said rotatable attachment rotates.

2. A hand held device as claimed in claim 1 wherein said rotary attachment includes an annular plate forming a periphery thereof, said shaft being a hollow shaft forming the centre thereof, a plurality of hollow arms extending from said shaft to said annular plate, the interior of each of said hollow arms being in communication with the interior of said shaft, each arm having an opening therein at a point therealong, and each said arm having fixed thereto a flexible blade with an aperture therein joining to 15 said opening in its associated arm.

3. A hand held device as claimed in claim 2 wherein each said point for said opening S, is different for each arm, each said blade is set at a given angle with respect to the horizontal, each blade having a front spreading plate with said aperture therein, a manifold joining said aperture to said opening and a flexible resilient gasket between said manifold and said front spreading plate.

4. A hand held device as claimed in claim 3 wherein there are four said arms arranged a twisted cruciform array with said blades attached to an outermost part of each said arm. A hand held device as claimed in claim 3 wherein there are four said arms arranged in an X-shaped array.

6. A hand held device as claimed in claim 3, claim 4 or claim 5 wherein said annular plate further includes a plurality of secondary blades fixed thereto at positions which are intermediate where said blades are fixed to said arms.

7. A hand held device for applying fluent material to or working fluent material on a surface including a housing, a motor attached to said housing for driving a detachable head portion, a hub driven by said motor to which said detachable head portion is attached, a handle for holding said device for guidance, means for supplying power to said motor, and means for supplying a moisturising agent to the region of said detachable head portion.

8. A hand held device as claimed in claim 7 wherein said detachable head portion includes a circular plate with an attachment for applying fluent material to or for working fluent material on said surface removably fixed to said plate.

9. A hand held device as claimed in claim 8 wherein said detachable head portion includes a plate having a toothed wheel co-axial with said motor and attached to the centre of said plate, said motor driving said wheel via a chain or belt. A hand held device as claimed in claim 7 wherein said detachable head portion includes a hollow drive shaft means supported by bearing means for rotation within said hub and having a toothed gear wheel means fixed thereto, a plurality of hollow see radial tubular arm means extending from said shaft means, the interior of each said °arm communicating with the interior of said hollow shaft means, apertures in each ~said arm means arranged at a radial distance from said shaft varying from arm to .o.o 15 adjacent arm, and blades fixed to each said arm means for spreading said fluent material.

11. A portable power unit for powering a remote device, the portable power unit including a fluidic power source, a fluidic reservoir for supplying the fluidic power source with fluid including an outlet from the reservoir and a fluid return means for seoe 20 returning fluid to the reservoir, means for supplying a moisturising agent from a *oO° moisturising agent reservoir and electric power supply means, including switch "•means, for powering said fluidic power source and said moisturising agent supplying "o means, said portable power unit having at least one fluidic power outlet and at least one moisturising agent outlet for supply of said fluid and said moisturising agent respectively to a remote location.

12. A portable power unit as claimed in claim 11 wherein said fluidic power source is hydraulic and said moisturising agent is water.

13. A portable power unit as claimed in claim 11 wherein said fluidic power source is hydraulic and said moisturising agent is oil.

14. A system for applying fluent material to or working fluent material on a surface including a portable power unit as claimed in any one of claims 11-13 wherein said remote device is a hand held device as claimed in any one of the claims 1-6. A system for applying fluent material to or working fluent material on a surface including a portable power unit as claimed in any one of claims 11-13 wherein said remote device is a hand held device as claimed in any one of the claims 7-10.

16. A system for applying fluent material to or working fluent material on a surface substantially as hereinbefore described with reference to the accompanying drawings.

17. A hand held device for applying fluent material to or working fluent material on a surface substantially as herein before described with reference to Fig 1, Fig 3, or Fig 4 of the accompanying drawings.

18. A hand held device for applying fluent material to or working fluent material on a surface substantially as herein before described with reference to Fig 2, 2a, 2b, or Figs 8-11 of the accompanying drawings.

19. A portable power unit substantially as herein before described with reference to Figure 7 of the accompanying drawings.

20. An apparatus for preparing fluent material for use mixing and pumping fluent material to a remote location, said location including a hand held device or a work site for use of the fluent material, said apparatus including mixing means for mixing dry and wet ingredients together on demand to form a fluent material, means to deliver said fluent material to pumping means for pumping said fluent material, said pumping means including first means for maintaining said fluent material in motion whether said fluent material is or is not on demand and second means, connecting to said first o means, for pumping said fluent material through an outlet when a demand for said fluent material is made; power means for supplying power to said mixing means and to said pumping means; and controlling means for controlling said power means to supply power selectively to said mixing means and to said first means and/or said second means of said pumping means as a function of at least said demand including

21. An apparatus for preparing fluent material for use substantially as herein before described with reference to Figure 5 of the accompanying drawings.

22. A table for use with fluent material including a working surface having an opening therein through which delivery of fluent material is made, fluent material supply means connectable to said opening including means for terminating said delivery, and means for supplying a moisturising agent at or near said opening to wet said fluent material including means for controlling the supply of said moisturising agent.

23. A table for use with fluent material substantially as hereinbefore described with reference to figure 6 of the accompanying drawings. Dated this 7 th day of April 2000 DANIELE COSTANTIN e