GB1600096A

GB1600096A - Filler gun for heat insulating material

Info

Publication number: GB1600096A
Application number: GB2074378A
Authority: GB
Original assignee: Shell Internationale Research Maatschappij BV
Current assignee: Shell Internationale Research Maatschappij BV
Priority date: 1977-09-02
Filing date: 1978-05-19
Publication date: 1981-10-14
Also published as: NL182975B; NL7709666A; BE869935A; NL182975C

Description

(54) FILLER GUN FOR HEAT INSULATING MATERIAL (71) We, SHELL INTERNATZONALE RE SEARCH MAATSCHAPPH B.V., a company organised under the laws of The Netherlands, of 30 Carel van Bylandtlaan, The Hague, The Netherlands, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The invention relates to a filler gun for the introduction of heat insulation material, consisting of a mixture of a granular solid and a binder, into an air-filled space between two walls, for instance a wall cavity.

With a view to heat economy, houses fitted with cavity walls are being insulated on a large scale by introducing heat insulating material into the narrow cavity between the walls. The granular material is mixed with a binder in the filler gun and then immediately introduced into the cavity.

At that moment the flow properties of the mixture are still so good that the mixture can move freely. The cavity is filled uniformly. After a short time evaporation of the solvent or the diluent of the binder effects a permanent adhesion and the granules are fixed in their places. This is essential to prevent the outflow of granules from ventilating holes, etc., which could lead in the long run to collapse of the insulating material. Suitable materials are vermiculite, perlite, hard granular foam particles, 1-10 mm in size. Hard foam formed by expanded polystyrene with a specific weight of 10-15 g/l is very suitable.

The binder may be material which under the given conditions changes from a readily flowing substance into a highly adhesive one in about one hour, for instance by evaporation of a diluent. A suitable material is an emulsion of latex in water. By evaporation of water a smooth water-repellent layer forms on the granules, which permanently binds the granules. A synthetic polymeric latex such as a vinyl acetate copolymer has been found to be very suitable.

Besides for the filling of wall cavities, this method can also be used for the introduction of insulating material into any doublewalled system, such as storage vessels, tanks and the like of large dimensions. This method may also be used in the construction of heat insulating building elements, such as blocks, panels, etc.

When heat insulating systems are formed in this way, it is very important to have the disposal of a convenient and effective filler gun. For instance, in the insulation of existing houses and buildings the mixture must be introduced through a small opening in the outer wall by a person standing high up on a ladder. This has to be done in various places. The filler gun must therefore be easy to handle. Further, precautions have to be taken to ensure that the filler gun is not blocked by the sticky mass formed in it. Existing filler guns for such applications do not satisfy the abovementioned requirements and the invention now indicates how these shortcomings can be obviate & The invention therefore relates to a filler gun suitable for the introduction of a mixture of granular solid and a binder into an air-filled space, which comprises a mixing chamber having a tubular exit nozzle whose axis is in common with the axis of the mixing chamber, and inlet ports adapted to receive a supply line for the granular solid and a supply line for the binder, wherein that inlet port adapted to receive granular solid incorporates a rigid riser, which is located beside the mixing chamber and runs substantially perpendicular to the axis thereof and which is connected to the mixing chamber in a backward loop so that it enters the mixing chamber directed towards the nozzle at an angle smaller than 90 , calculated relative to the said axis.

The granular solid is conducted with a transport gas, usually air, through the riser to the mixing chamber, where mixing with the binder takes place; The binder is supplied under pressure. Immediately thereafter the mixture leaves the filler gun through the nozzle. Of course, it is always possible that owing to unforeseen circumstances the outflow through the nozzle stops.

When a wall cavity is filled, this can be due, for instance, to the presence in the cavity of unknown obstacles inadvertently left there during construction. The two streams to the mixing chamber are set manually, independently of each other.

When the outflow stops, the supply of the granular solid will rapidly come to an end.

From the venturi system discussed further on, the granules will be blown through the riser, but the supply of binder goes on so long as it is not shut off. The mixing chamber rapidly fills up then. There is a considerable risk then that binder will also find its way into the supPly line for the granular solid. Since the filTer gun is usually connected by a long flexible supply line, for instance a rubber hose, with a storage vessel for the granular solid standing on the ground, the binder may also find its way into that flexible line, which means that this line cannot be used anymore. Now, by introducing the granular solid into the mixing chamber from the top via a riser and a backwardly curving loop, a kind of buffer space has been made, in which in the event of a stop of the outflow of the mixture the initially continuing supply of binder can be collected. The operator has more time to shut off the supply of binder.

The afore-mentioned angle at which the supply line for the granular solid enters the mixing chamber is preferably 30-50". At such an angle there is a sufficiently smooth flow of the granular solid.

The riser is preferably dimensioned and fitted in such a way that it may serve as handle and, with the gun in the operating position the loopshaped piece is above the mixing chamber. t is a considerable advantage that the downwardly directed force exerted by the long flexible supply line operates in the longitudinal direction of the handle. For this implies that the filler gun will not turn over when being handled.

This handle function can be achieved in a simple manner by combining the loop shaped piece and the metal riser into one rigid whole and by having the riser continue to an appropriate length under the mixing chamber. It may be preferred to make the loop4ormed piece flexible, for instance, to facilitate cleaning or q,uick replacement in case of clogging. In that case the rigid riser will be attached ta the mixing chamber, The section of the mixing chamber near the nozzle is preferably venturi-shaped and equipped with supply channels for a transport gas directed to the nozzle. This causes a reduced pressure in the mixing chamber, as a result of which the granular solid is sucked in. Particularly with very light particles such as expanded polystyrene this system yields excellent results. In most cases the transport gas is air, which is supplied at a gauge pressure of, for instance, 3 bar via a compressor.

The same air pressure may be used to pressurize the vessel in which the binder is present. The supply line for the binder preferably ends as an atomizing head at the inlet of the mixing chamber. A suitable atomizer is one as used for atomizing oil in furnaces. This way of introducing the binder has the considerable advantage over the customary siphon atomization that during atomization there is hardly any drop in temperature or none at all. With siphon atomization this drop may be 10-14"C by evaporation of water. The latex emulsion becomes too cold then for it to spread out sufficiently to form a film around the granules when it meets the granular solid.

With atomization under pressure the adhesive still has nearly the ambient tempera ture when it meets the granular solid.

The invention will now be explained with the aid of two figures, which give views of a filler gun according to the invention.

In the side view of Fig. 1 the mixing chamber is indicated by 1. Supply line 2 for a granular solid consists of a rigid riser 3 and a loop-shaped piece 4. The internal diameter of the riser may be 35 mm. To the bottom end of riser 3 a hose can be connected of sufficient length to supply the granular solid from a storage vessel. This has not been indicated further. Loop 4 is connected here to the mixing chamber 1 at an angle of 45 .

The binder is supplied through supply line 5 which is equipped with valve 6. Tube 7 extends inside to a point just before the mixing chamber and ends in a pressure atomizer 8. 'the pressure can be read on pressure gauge 9.

Through supply line 10, equipped with valve 11, air is supplied under pressure.

The section where supply line 10 opens into the mixing chamber is venturi shaped (12) and is equipped with feed channels 13 directed to nozzle 14. The pumping effect of the air fiow causes the granular solid to be sucked in via supply line 2. The air pressure can be read on pressure gauge 15.

Fig. 2 shows a front view. Parts present in Fig. 1 have been numbered correspondingly. Fig, 2 gives an idea of the way in which riser 3 mry be used as handle.

WHAT WE CLAIM IS:- 1. A filler gun suitable for the introduction of a mixture of granular solid and a binder into an air-filled space, which comprises a mixing chamber having a tubular exit nozzle whose axis is in common with the axis of the mixing chamber. and inlet ports adapted to receive a supply line for the granular solid and a supply line for the binder, wherein that inlet port adapted to

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **.

When a wall cavity is filled, this can be due, for instance, to the presence in the cavity of unknown obstacles inadvertently left there during construction. The two streams to the mixing chamber are set manually, independently of each other.

When the outflow stops, the supply of the granular solid will rapidly come to an end.

From the venturi system discussed further on, the granules will be blown through the riser, but the supply of binder goes on so long as it is not shut off. The mixing chamber rapidly fills up then. There is a considerable risk then that binder will also find its way into the supPly line for the granular solid. Since the filTer gun is usually connected by a long flexible supply line, for instance a rubber hose, with a storage vessel for the granular solid standing on the ground, the binder may also find its way into that flexible line, which means that this line cannot be used anymore. Now, by introducing the granular solid into the mixing chamber from the top via a riser and a backwardly curving loop, a kind of buffer space has been made, in which in the event of a stop of the outflow of the mixture the initially continuing supply of binder can be collected. The operator has more time to shut off the supply of binder.

The afore-mentioned angle at which the supply line for the granular solid enters the mixing chamber is preferably 30-50". At such an angle there is a sufficiently smooth flow of the granular solid.

The riser is preferably dimensioned and fitted in such a way that it may serve as handle and, with the gun in the operating position the loopshaped piece is above the mixing chamber. t is a considerable advantage that the downwardly directed force exerted by the long flexible supply line operates in the longitudinal direction of the handle. For this implies that the filler gun will not turn over when being handled.

This handle function can be achieved in a simple manner by combining the loop shaped piece and the metal riser into one rigid whole and by having the riser continue to an appropriate length under the mixing chamber. It may be preferred to make the loop4ormed piece flexible, for instance, to facilitate cleaning or q,uick replacement in case of clogging. In that case the rigid riser will be attached ta the mixing chamber, The section of the mixing chamber near the nozzle is preferably venturi-shaped and equipped with supply channels for a transport gas directed to the nozzle. This causes a reduced pressure in the mixing chamber, as a result of which the granular solid is sucked in. Particularly with very light particles such as expanded polystyrene this system yields excellent results. In most cases the transport gas is air, which is supplied at a gauge pressure of, for instance, 3 bar via a compressor.

The same air pressure may be used to pressurize the vessel in which the binder is present. The supply line for the binder preferably ends as an atomizing head at the inlet of the mixing chamber. A suitable atomizer is one as used for atomizing oil in furnaces. This way of introducing the binder has the considerable advantage over the customary siphon atomization that during atomization there is hardly any drop in temperature or none at all. With siphon atomization this drop may be 10-14"C by evaporation of water. The latex emulsion becomes too cold then for it to spread out sufficiently to form a film around the granules when it meets the granular solid.

With atomization under pressure the adhesive still has nearly the ambient tempera ture when it meets the granular solid.

The invention will now be explained with the aid of two figures, which give views of a filler gun according to the invention.

In the side view of Fig. 1 the mixing chamber is indicated by 1. Supply line 2 for a granular solid consists of a rigid riser

3 and a loop-shaped piece 4. The internal diameter of the riser may be 35 mm. To the bottom end of riser 3 a hose can be connected of sufficient length to supply the granular solid from a storage vessel. This has not been indicated further. Loop 4 is connected here to the mixing chamber 1 at an angle of 45 .

The binder is supplied through supply line 5 which is equipped with valve 6. Tube 7 extends inside to a point just before the mixing chamber and ends in a pressure atomizer 8. 'the pressure can be read on pressure gauge 9.

Through supply line 10, equipped with valve 11, air is supplied under pressure.

The section where supply line 10 opens into the mixing chamber is venturi shaped (12) and is equipped with feed channels 13 directed to nozzle 14. The pumping effect of the air fiow causes the granular solid to be sucked in via supply line 2. The air pressure can be read on pressure gauge 15.

Fig. 2 shows a front view. Parts present in Fig. 1 have been numbered correspondingly. Fig, 2 gives an idea of the way in which riser 3 mry be used as handle.

WHAT WE CLAIM IS:- 1. A filler gun suitable for the introduction of a mixture of granular solid and a binder into an air-filled space, which comprises a mixing chamber having a tubular exit nozzle whose axis is in common with the axis of the mixing chamber. and inlet ports adapted to receive a supply line for the granular solid and a supply line for the binder, wherein that inlet port adapted to

receive granular solid incorporates a rigid riser which is located beside the mixing chamber and runs substantially perpendicular to the axis thereof, and which is connected to the mixing chamber in a backward loop so that it enters the mixing chamber directed towards the nozzle at an angle smaller than 90 , calculated relative to the said axis.
2. A filler gun according to claim 1, characterized in that the angle at which the supply line for the granular solid enters the mixing chamber is 30-50".
3. A filler gun according to claim 1 or 2, characterized in that the riser is dimensioned and fitted in such a way that it may serve as a handle and with the gun in the operating position, the loop-shaped piece is above the mixing chamber.
4. A filler gun according to any one of claims 1-3, characterized in that under the handle the riser is connected to a flexible supply line for the granular solid.
5. A filler gun according to any one of claims 1-4, characterized in that the section of the mixing chamber near the nozzle is venturi-shaped and equipped with feed channels for a transport gas directed to the nozzle.
6. A filler gun according to any one of claims 1-5, characterized in that the supply line for the binder is connected to a vessel in which the binder is present under pressure, which supply line ends as an atomizing head at the inlet of the mixing chamber.
7. A filler gun according to claim 1 and as described hereinbefore, in particular with reference to the figures.