GB1583882A - Apparatus for dispensing fluid or fluidised material - Google Patents

Description

(54) APPARATUS FOR DISPENSING FLUID OR FLUIDIZED MATERIAL (71) We, MUANYAGIPARI KUTATO INTEZET, a body corporate organised under the laws of Hungary, of 114, Hungaria korut, Budapest XIV, Hungary, 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 present invention relates to apparatus for dispensing fluid or fluidised material, for example incorporating a hand-held spray gun.

Hand held guns for dispensing synthetic resins are known. In use they are usually connected through flexible hoses to receptacles from which one or more components to be dispensed are fed to the gun under positive pressure possibly together with an atomizing airstream.

Known guns incorporate a valve or valve system which is usually mechanically oper ated. The operation of the valve permits dispensing of one or more components, which may for example include synthetic resins, a catalyzer or hardener for the resin, a dye stuff, and compressed air to atomize the dispensed liquids. In certain cases, two or more valves may be provided, for example when chopped glass fiber is dispensed in combination with a synthetic resin, in which case valving must be provided for the resin, for the catalyzer, for the atomising air, and for compressed air that actuates the glass fiber chopper.

The valve arrangements in guns known heretofore have substantial drawbacks, since the valves are rather complicated and increase the weight of the guns. In order to be able to reduce weight, it has been proposed to miniaturize the valves; but this decreases the useful life and operational reliability of the gun. Problems are also encountered in connection with the sealing of the valves, due in part to the need to keep the guns small and light in weight. If the valves are unreliable, the dispensed material may contact the skin of the operator, with undesirable results.

Also, when a pigment or pigmented resin is dispensed, a problem arises when it is desired to change the color of the dispensed material. Due to their complicated construction, simple flushing of the valves is impossible. Therefore, when changing to a dyestuff of different color, the whole gun must be disassembled.

Finally, the physical effort of actuating valves on known guns, over long periods of time, can be quite tiring to the operator, particularly when a plurality of valves is involved.

Accordingly, it is an object of the present invention to provide apparatus for dispensing fluid or fluidised material in which the above drawbacks are mitigated or overcome.

According to the present invention we provide aparatus for dispensing fluid or fluidised material comprising; a hand held dispenser, a plurality of valves each having at its inlet side means for connection to a source of material under pressure and connected on its outlet side to a flexible conduit coupled for material transfer to the dispenser, a plurality of orifices on said dispenser that may be selectively opened or closed by the operator, and a plurality of conduits coupled to said dispenser each for interconnecting a respective orifice with a source of air under pressure so that opening or closing an orifice will cause a pressure change in the respective conduit, and means responsive to said pressure changes to actuate said valves, whereby said valves may selectively be actuated for the control of material therethrough by opening or closing selected If desired there can be a separate orifice orifices.

on the dispenser for the control of each component or orifices may be arranged so that one orifice is provided for the control of one or more of the components and one or more orifices is or are provided for the control of a plurality of the components. By "components", as indicated above, is meant gaseous, liquid and solid components, the gaseous component ordinarily being air, the liquid components being, for example, synthetic resin, hardener or catalyst for the same, dyestuffs, flushing solvents, etc., and the solid component often being chopped glass fibre. As indicated above, the orifices can also control the actuation of the chopper for glass fibre, for example by control of a stream of compressed air that operates the chopper.

The orifices can be directly opened or closed by the fingers or hand of the operator; alternatively, they can be indirectly opened or closed by means of keys operated by the fingers or hand of the operator, much in the manner of a wood-wind musical instrument.

Embodiments of the invention are now described by way of example only with reference to the accompanying drawings, in which: Fig. 1 is a schematic view of the apparatus for dispensing a plurality of materials in accordance with the present invention; and Fig. 2 is an enlarged cross-sectional view of a hand held gun which can be used in a dispensing apparatus in accordance with the present invention.

Referring to Fig. 1, this shows an apparatus for dispensing fluid or fluidised material comprising a hand held gun, connected by flexible conduits 18, 19, 20 to the outlet sides of valves 26, 27, and 28, the inlet sides of which valves are connected via suitable lines to vessel 21, 22 and 23 respectively which each hold one of three fluid or fluidised materials to be dispensed, one of said fluid components being, for example, polyester resin. The gun mounts a glass fibre chopper 24 which is actuable by compressed air from a flexible conduit 25, which is connected, via a valve 29, to a source of compressed air. The valves may each comprise a valve chamber and a valve element moveable in the chamber from a position preventing fluid flow from the respective vessel 21, 22, or 23 into respective line 18, 19, 20, to a position permitting such flow. For instance the element may be a piston, moveable in a chamber between a position in which it blocks inlet and outlet holes for the lines into and out of the chamber and a position in which it forms one wall of the sealed chamber through which fluid may flow from one of the holes to the other. Beneath the piston chamber is an auxiliary chamber including a second piston connected to the first piston so that the first piston moves with the second piston. The second piston divides the auxiliary chamber into two parts, in one of which a coil compression spring is located, acting on a wall of the chamber and the piston to urge the piston to a position such that the first piston will close the holes; the other part of the auxiliary chamber is connected via an air line (30', 31', 32', 33') to an actuator (30, 31, 32, or 33) in the valve. Each actuator comprises a chamber with three openings: the first connecting the chamber via an air line (30', 31', 32', 33') to the said other part of the auxiliary chamber; the second opening connecting the chamber via an air line to a source of air under pressure (see arrowed lines), and the third opening connecting the chamber via an air line (34, 35, 36, 37) to an orifice (38, 39, 40, 41) on the handle of the gun.

A spring in each actuator urges a piston to a position in which the opening to line 30', 31', 32' or 33' is closed; the other openings remaining unsealed. The arrangement is such that compressed air from the lines indicated by arrows continuously bleeds through lines 34, 35, 36, or 37 and out of orifices 38, 39, 40, 41 so that the pressure in the actuator chamber does not rise high enough to move the actuator piston against the actuator spring as long as the orifice is open, so that the openings to lines 30', 31', 32', 33' remain closed. When a respective orifice is closed, e.g. by placing a finger over it, the pressure in the line 34, 35, 36, or 37 and thus in the respective actuator builds up, forcing the piston back against the pressure of the spring, until the opening to line 30', 31', 32', 33' is uncovered and the pressure in the chamber is transmitted to the auxiliary chamber. In response to the increase in pressure in the said other part of the auxiliary chamber the second piston is forced against the pressure of the compression spring, thus causing corresponding movement of the first piston to a position in which the aforementioned holes are nncovered, and fluid or fluidised material may flow through the valve to the dispenser.

The flow of each of the aforementioned components is controllable. It will be appreciated that by providing each of conduits 18, 19, 20, and 25 with an individual valve 26, 27, 28, and 29, the flow of each of the three aforementioned components is separately controllable by the at least partial closure of the respective one of the orifices.

Needless to say, the actuators 26-29 could be arranged in reverse configuration, so that the application of pneumatic pressure thereto moves them from the open to the closed position. In that case, of course, dispensing would take place when the orifice or orifices on the gun handle are open and would be terminated by closing the orifice or orifices.

Fig. 2 shows in greater detail a gun for dispensing synthetic resins such as polyester resin and chopped glass fibre, using apparatus similar to that disclosed with respect to Fig. 1. Apart from the conduits and orifices on the handle, the gun is of conventional construction and is provided with passageways for the separate introduction of a stream 42 of polyester resin and a stream 43 of catalyst therefor, into the mixing chamber 44 of the gun, and for the dispensing of the mixed resin and catalyst through a nozzle 45 that is surrounded by a conventional air cap 46 fed by a stream 41 of compressed air.

A stream 48 of solvent can be provided, for flushing out mixing chamber 44 to prevent the buildup therein of mutually reactive materials at the end of dispensing.

A glass fibre chopper 49 is actuated by a stream 50 of compressed air thereby to chop into short lengths glass fibre sliver or roving 51 that is supplied to chopper 49, all in a conventional manner.

In the described apparatus individual streams of compressed air 52, 53 and 54 are bled via individual flexible conduits, as in Fig. 1, to and through small orifices 55, 56 and 57, respectively, in the handle of the gun. However, Fig. 2 illustrates the instance in which some of the orifices are individual to actuators and valves operable to control a single fluid stream while another of the orifices is operatively associated with an actuator and respective valve or valves operable to control a plurality of streams.

Specifically, in the Fig. 2 arrangement, the conduit 52 supplying orifice 55 with compressed air is connected to an actuator for a valve which controls the supply 48 of flushing solvent. The orifice 56 is connected to an actuator for a valve which controls the stream of compressed air 50 that operates glass fiber chopper 49; and the orifice 57 is connected to an actuator for a valve cr valves which control(s) the streams 42, 43 and 41 of resin, catalyst and compressed air, respectively, that flow through the gun.

Thus, by selective individual opening and closing of the orifices 55-57, it is possible selectively to dispense mixed atomized resin and catalyst, with or without chopped glass fiber, and thereafter to flush the mixing chamber with solvent.

In the preferred practice of the present invention the supply of controlled compressed air need be only at very low gauge pressure, for example 0.01-0.1 atmospheres.

Thus, the consumption of compressed air for this purpose is negligible. Moreover, as the actuators 30-33 can be constructed to be quite sensitive, it is not necessary completely to close the orifices on the gun handle: it suffices merely to choke or impede the opening thereby to alter the back pressure of the controlled compressed air to a sufficient degree. As indicated above, this control can be performed directly by the hand or fingers of the operator, or indirectly via keys.

Also, although fully pneumatic systems have been disclosed above, it is to be recognized that electropneumatic variations can also be resorted to.

Using the preferred apparatus in accordance with the present invention it is easy to change colors of the dispensed material.

Thus, if for example various dyestuffs are employed, then it is an easy matter to provide an individual conduit with an individual valve for each individual receptacle of dyestuff or resin containing dyestuff, of a different color. It is thus not necessary to clean the valves, because the valves are always immersed in material of the same color. It suffices merely to flush the mixing chamber and then to start with a new color by the technique of manipulating a different set of orifices.

The preferred apparatus of the present invention is believed to have the following advantages over previously known apparatus: 1. The weight of the spray gun compared to known spray guns and the like, can be greatly reduced, for example, by 40 to 60%.

2. As the valves can be mounted remote from the gun on some fixed portion of the apparatus, it is possible to construct the valves quite strongly and so they operate with greatest safety and reliability.

3. The use of impulse air for operating the valves according to the present invention is much quicker than by manual operation as used in known apparatus.

4. The hand-held gun operates quite reliably, because it need have no moving parts.

5. Operation of the gun is much easer, because the work of manually opening and closing valves is not required.

6. The flexible conduits between the gun and the stationary control valves are not under pressure when the gun is out of operation; and this is quite important for safety purposes and also to ensure long life of the conduits.

7. As indicated above, it is quite easy to change colors quickly and easily.

The use of preferred apparatus in accordance with the present invention will now be described in the following examples.

EXAMPLE I Apparatus as described above with reference to Fig. 2 is used, for dispensing mixed polyester resin and catalyst therefor at a rate of 5 kilograms per minute. The orifices in the handle have a diameter of 1.5 mm; the inside diameter of the small conduits for the impulse or pressure air is 1 mm, and the pressure of the impulse or control air is 15.2 psia, which is 0.5 psig, or about 0.034 atmospheres. The resin and catalyst are delivered to the gun under a pressure of 158 psig, and the pressure of the compressed air both to the gun and to the glass fiber chopper is 100 psig. Flushing solvent is delivered at a pressure of 72 psig. The weight of the gun is about half that of guns known heretofore for similar purposes and of the same capacity.

EXAMPLE 2 Apparatus is provided for spraying from a gun polyester gel resins selectively individually in the colors red, green and yellow, the resin component in each case being pig mented. Thus, there are three storage containers for resins, one for red, one for green, and one for yellow, as well as a storage container for catalyzer and a source of compressed air, as well as a source of solvent under pressure. Four orifices are provided on the gun handle. When one of these orifices is closed, red resin plus catalyzer plus compressed air are dispensed. Closure of the second orifice dispenses yellow resin plus catalyzer plus compressed air; while closure of the third orifice dispenses green resin plus catalyzer plus compressed air. The fourth orifice controls only the solvent flush, and is selectively closed in the interim between closure of two different ones of the other orifices, thereby to flush the mixing chamber when changing colors.

WHAT WE CLAIM IS: 1. Apparatus for dispensing fluid or fluidised material comprising: a hand held dispenser, a plurality of valves each having at its inlet side means for connection to a source of material under pressure and connected on its outlet side to a flexible conduit coupled for material transfer to the dispenser, a plurality of orifices on said dispenser that may be selectively opened or closed bq the operator and a plurality of conduits coupled to said dispenser each for interconnecting a respective orifice with a source of air under pressure so that opening or closing an orifice will cause a pressure change in the respective conduit, and means responsive to said pressure changes to actuate said valves, whereby said valves may selectively be actuated for the control of material therethrough by opening or closing selected orifices.

2. Apparatus according to Claim 1, wherein each valve is connected to the dispenser via a separate flexible conduit.

3. Apparatus according to Claim 1 or 2, wherein the dispenser has an elongate handle and the orifices are arranged in a row on the handle.

4. Apparatus according to any one of the preceding Claims, wherein the actuating means comprises a separate auxiliary valve connected to each said valve, the auxiliary valves being operable upon an increase in pressure in respective conduits to transmit said increase of pressure to said valves to open or close a fluid or fluidised material flow path therethrough.

5. A dispenser according to any one of the preceding Claims, further including a glass fibre chopper mounted on the dispenser, said chopper being actuable by compressed air to chop short lengths of glass fibre sliver or roving and dispense them in a stream of compressed air, the chopper being connected to the outlet side of one of said valves, the inlet side of which valve includes means for connection to a source of compressed air.

6. A dispenser for fluid or fluidised material, substantially as described herein, with reference to Fig. 1 or Fig. 2 of the accompanying drawings.

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

Claims (6)

**WARNING** start of CLMS field may overlap end of DESC **. EXAMPLE 2 Apparatus is provided for spraying from a gun polyester gel resins selectively individually in the colors red, green and yellow, the resin component in each case being pig mented. Thus, there are three storage containers for resins, one for red, one for green, and one for yellow, as well as a storage container for catalyzer and a source of compressed air, as well as a source of solvent under pressure. Four orifices are provided on the gun handle. When one of these orifices is closed, red resin plus catalyzer plus compressed air are dispensed. Closure of the second orifice dispenses yellow resin plus catalyzer plus compressed air; while closure of the third orifice dispenses green resin plus catalyzer plus compressed air. The fourth orifice controls only the solvent flush, and is selectively closed in the interim between closure of two different ones of the other orifices, thereby to flush the mixing chamber when changing colors. WHAT WE CLAIM IS:

1. Apparatus for dispensing fluid or fluidised material comprising: a hand held dispenser, a plurality of valves each having at its inlet side means for connection to a source of material under pressure and connected on its outlet side to a flexible conduit coupled for material transfer to the dispenser, a plurality of orifices on said dispenser that may be selectively opened or closed bq the operator and a plurality of conduits coupled to said dispenser each for interconnecting a respective orifice with a source of air under pressure so that opening or closing an orifice will cause a pressure change in the respective conduit, and means responsive to said pressure changes to actuate said valves, whereby said valves may selectively be actuated for the control of material therethrough by opening or closing selected orifices.

2. Apparatus according to Claim 1, wherein each valve is connected to the dispenser via a separate flexible conduit.

3. Apparatus according to Claim 1 or 2, wherein the dispenser has an elongate handle and the orifices are arranged in a row on the handle.

4. Apparatus according to any one of the preceding Claims, wherein the actuating means comprises a separate auxiliary valve connected to each said valve, the auxiliary valves being operable upon an increase in pressure in respective conduits to transmit said increase of pressure to said valves to open or close a fluid or fluidised material flow path therethrough.

5. A dispenser according to any one of the preceding Claims, further including a glass fibre chopper mounted on the dispenser, said chopper being actuable by compressed air to chop short lengths of glass fibre sliver or roving and dispense them in a stream of compressed air, the chopper being connected to the outlet side of one of said valves, the inlet side of which valve includes means for connection to a source of compressed air.

6. A dispenser for fluid or fluidised material, substantially as described herein, with reference to Fig. 1 or Fig. 2 of the accompanying drawings.