JPS5918600B2 - Delivery device for low stability fluids - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus adapted to deliver a low stability fluid from its container and to maintain the fluid within the container in a non-contaminated and non-pressurized condition.

The plastics industry and other industries use catalysts containing fluids of very low stability, such as organic peroxides.

Some fluid catalysts, such as methyl ethyl ketone peroxide, which have been combined with polyester resins to produce plastic articles and/or form plastic coatings on articles, may be subjected to mechanical shock or heat or It has a tendency to react explosively or decompose immediately when exposed to friction. In order to continuously supply such low-stability fluids to manufacturing equipment such as spray guns and injection heads, it is necessary to rely on large-volume, high-volume production techniques to operate economically. Large volumes of fluid must be maintained under pressure.

In conventional technology (or in order to supply the required amount of low stability fluid, for example, 3.78 m
Delivery is made from a pressurized tank containing 5 liters (1 gallon) or more of fluid.

The capacity of a commonly used pressurized tank is 7.570-1.
It is about 8.927 liters (2-5 gallons). However, storing such large quantities of low stability fluids under pressure in one container is potentially dangerous. The reason is that if a disaster were to occur, the entire amount of fluid would react violently and explosively.
Another hazard inherent in pressurized tanks is the potential for contamination of the fluid, which can occur if the fluid container, e.g.
This is because a liter (1 gallon) plastic bottle must be transferred to a pressurized tank under working conditions that are not at least clean and sanitary.

Furthermore, since this fluid comes into contact with and often mixes with the pressurized air, this also causes contamination. Such contamination presents other risks, such as causing the fluid to react explosively due to rapid oxidation of the contaminants, and thereby causing the entire fluid in the tank to explode on its own. This is the original. The object of the present invention is to overcome the above-mentioned drawbacks associated with the prior art by providing a device for delivering low stability fluids from their containers, while maintaining the fluids within the containers in a non-contaminated and non-pressurized state, while delivering small quantities. by providing a device capable of safely delivering low stability fluids one after the other at the required pressures in a continuous manner.

Another object of the present invention is to overcome the above-mentioned drawbacks associated with the prior art.
The process of delivering a low stability fluid from its container,
It is now possible to safely deliver small quantities of said fluid one after the other to its point of use in a substantially continuous and pressurized condition while maintaining the fluid within said container in a non-contaminated and non-pressurized condition. It is to remove it by subjecting it to a process.

According to the invention, therefore, a delivery device adapted to deliver a low stability fluid from its container and to maintain the fluid in said container in a non-contaminated and non-pressurized state, comprising an inlet and an outlet. a small volume pump device and an inlet tube device connecting an inlet of the pump to the fluid in the container, communicating with the fluid through an opening in the container, and substantially closing the opening; an inlet piping arrangement having a closure device for discharging fluid from the container through the inlet piping arrangement and into the pumping arrangement, the motor being operatively connected to the pumping arrangement for operating the pumping arrangement; suctioning and pressurizing the fluid in the pumping device at the pump outlet, such that the fluid is not pressurized in the container and only a small amount of fluid is subsequently pressurized at any time; A delivery device is obtained having a motor.

Still in accordance with the present invention, in the process of delivering a low stability fluid normally supplied by a non-contaminated, non-pressurized container of suitable volume, a suction tube is inserted into said container and the suction tube is closing said container at ambient temperature to maintain said fluid in a non-pressurized and non-contaminated condition; withdrawing a small amount of fluid from said container separately; and applying each small amount of fluid separately. and supplying each of the separately pressurized small quantities of fluid to its point of use, the pressurizing and withdrawing step transferring the first small quantity of fluid from the container to a second. while drawing out a small amount of fluid, and after the pressurized first small amount of fluid is discharged, pressurizing the second small amount of fluid, and the second small amount of fluid is pressurized. withdrawing a third small quantity of fluid from said container at the same time as said container is being used, said steps being carried out one after the other to provide said fluid substantially continuously to the point of use, further causing a disaster. The result is a process that is adapted to quickly relieve the overpressure condition and stop the increase in fluid pressure when the fluid pressure is released.

Next, embodiments of the present invention will be described with reference to the accompanying drawings. 1st
The fluid delivery system of the present invention, designated generally by 10 in the Figures, is particularly adapted to transport a low stability fluid, such as a catalyst, such as methyl ethyl ketone peroxide, into a normally pressurized container 1.
Spray gun 1 through hose 15 from one of 2 and 14.
Suitable for supplying 6.

The spray gun 16 is still supplied with a resin compatible with the catalyst through a hose 18 so that the catalyst and resin are sprayed and simultaneously mixed by the gun operator. In conventional catalyst systems with a small ratio of catalyst to resin, air can be pumped by an air hose 20 into the catalyst tube 15 adjacent to the gun for purposes described below. The delivery device 10 is a foundation 2
2, on which various components of the apparatus are mounted.

The foundation has a central portion 24 and a pair of legs 26 extending downwardly.
, and a pair of outwardly extending horizontal platforms 2γ for supporting a pair of fluid containers 12,14. A feature of the device is that it is configured to use standard containers 12, 14, eliminating the need to transfer fluid to special containers. This feature reduces the risk of contaminating the fluid and avoids unnecessary effort. The foundation can be hung on a wall if desired.
The apparatus 10 features a pair of pump assemblies 27, 28 which, for convenience of explanation, will be referred to as the right and left assemblies, respectively.

The pump assembly 2 as shown in FIGS. 1 and 2
7, 28 have common top and bottom headers and are mounted on foundation 22 as one unit. The two assemblies are partially surrounded by a thin sheet metal shield 29 which has decorative purposes as will be explained below and is adapted to serve as a deflection safety shield. The shield is removably held in place by a spring 31 (FIG. 2) and fits into grooves 32 formed in the upper and lower portions of the pump assembly body. Since the two pump assemblies are of the same construction, only the right assembly 27 will be described.

To clarify the operation of this pump, assembly 528
Although some of the corresponding components have been given different reference numerals, the structure is similar to that described below. Pump assembly 27 includes a single-acting piston pump for delivering the low stability fluid and a reciprocating piston air motor for reciprocating the pump piston. As shown in FIG. 3, the pistons and cylinders for the pump and air motor are housed within a common heat dissipating aluminum body 36.

The body 36 is generally cylindrical and has an inner diameter or cylinder 38 formed at its upper end that extends below one half of the body 36 to define a fluid pumping chamber 40. The fluid pumping chamber of assembly 28 is designated by 41 to facilitate understanding of the operation of the pump. The cylinder 38 is impregnated with polytetrafluoroethylene, such as Teflon 2 or NiTuff, to lubricate the surface and isolate the aluminum from the catalyst. It is closed.

This cylinder head 42 can be made of aluminum coated with polytetrafluoroethylene since it is not subject to the action of catalysts and heat dissipation sources. Said head 42 has a sealing ring 4 positioned in its groove.
4 and sealed to the cylinder 38 by the bolt (
It is held to the cylinder by a suitable fastening device, such as (not shown). A pair of one-way valves 46, 48 are positioned within cylinder head 42, with valve 46 being a fluid inlet valve and valve 48 being a fluid outlet valve. The valves 46, 4
8 is received within a threaded hole 50 in the cylinder head for easy removal and replacement if necessary. A pump piston 52, preferably formed of polyethylene, vinylidene fluoride-chlorotrifluoroethylene copolymer, or other material compatible with the catalyst, is mounted for reciprocating movement within the cylinder 38.

The piston 52 is sealed to the cylinder 38 by a two-piece sealing ring assembly 53 carried within its groove. In order to minimize the risk of fluid action in the pump chamber, the dimensions of the inner diameter 38 and the piston 52 forming this chamber are such that the catalyst
It is designed to fill only 6.7 grams (2 ounces). A tubular skirt 56 is suspended from the piston 52;
The skirt is adapted to be connected to an air motor as described below. The inner diameter of the main body 36 below the chamber 40 is 5
It is enlarged as indicated by 8 to form a cylinder 60 for the piston of a double acting air motor.

The lower end of the cylinder 60 is closed by a cylinder head 62 which is sealed against the cylinder wall by a sealing ring assembly 64 carried in its groove.
and is held to body 36 by a suitable fastening device such as a bolt (not shown).

Said bolt connects both heads 42 and 62 to cylinder body 3.
6. A pair of screw holes 66 and 67 are provided in the head 62 so that a supply/vent connection member 70 and a pilot connection member 72 can be screwed into each other. Air motor pistons 74, formed of a suitable low friction alloy such as Delrin, are reciprocally mounted within both cylinder bores 38,60.

Specifically, the piston has a small diameter upper portion 76 slidably mounted within the pump cylinder 38 and an air motor inner diameter 6.
The large diameter portion 80 is reciprocatably mounted within the 0. The two piston portions are each sealed within a corresponding inner diameter by a sealing ring assembly 82,84. The lower surface 92 of the piston portion 80 drives the piston upwardly by a fluid displacement stroke when compressed air is supplied through the coupling member 70, and its annular upper surface 92
drives the piston downward during the fluid suction stroke. Due to the different areas of the two piston surfaces, compressed air is continuously supplied to the upper motor chamber 86 through the port 88 in the body 36, whereas the lower motor chamber 90 is supplied intermittently through the connecting member 70. be done. To facilitate later explanation of operation, chambers of assembly 28 which are equivalent to chambers 86, 90 of assembly 27 are designated by reference numerals 87, 91, respectively. An elongated recess 94 is provided in the center of the lower portion of the motor piston 74 for receiving a hollow mandrel 96 of the pilot coupling member 72.

In the uppermost part of the stroke of the piston 74, the mandrel 9
6 is a sealing ring 98 carried by a groove in a recess 94;
is sealed against the piston. The upper tip of the mandrel 96 is cut away, as indicated by 100, to allow passage of a small amount of compressed air from the chamber 90 near the end of the upward stroke of the piston 74 for purposes described below. The upper end portion of the air motor piston 74 is formed with an annular recess 109 in which the pump piston 52 is inserted.
The lower end of the skirt 56 is telescopically received and is adapted to cause the pump piston to reciprocate according to the filling and extrusion strokes, respectively, when compressed air is supplied to the chambers 86 (or 87) and 90 (or 91). . In order to avoid damage to the pump chamber 40 (or 41) due to the forceful action of the fluid and to keep the pressure in the pump chamber to a minimum, the connection between the two pistons is open, i.e. pressed. It has become possible to crush it. By connecting the pistons in a collapsible manner, the pump piston 52 is able to move beyond the normal end position of its downward stroke so that the piston 5
When the piston 52 moves downward into the space existing between 2 and 74 and reaches the 2-squeezed position, and the lower surface 102 of the piston 52 comes into contact with the upper surface 104 of the piston 74, the volume of the pump chamber is quickly reduced. can be increased to For this purpose, a plurality of radially extending shear pins 105 are disposed around piston 74 and skirt 56 and engage mating bores in the skirt and piston. The diameter of the holes and the size and number of shear pins provide adequate strength for normal operation of the pump, and when severe fluid action occurs within the pump chamber, the pins are sheared and the skirt 56 is pushed into the recess 109. It is designed so that it can be nested inside. If desired, fewer pins can be inserted to vary the pressure at which the pump piston is crushed into the air motor piston. skirt 5
The openings 111, 113 formed in the recess 109 and the inside of the skirt 56 are for ventilating the interior of the recess 109 and the skirt 56, and to prevent a delay in the downward movement of the piston 52 when crushing is performed. . In addition to the pressure being released by the sudden increase in the volume of the pump chamber 40 as the pin 105 is sheared and the pump piston is crushed into the motor piston, the pressure between the two pistons is A plurality of large-area pressure safety ports 110 are provided in a portion of the main body 36 adjacent to the cavity.

Once the pump piston is crushed, the port 110 immediately opens to release the pressure caused by the explosion to the atmosphere. All of the pressure relief ports 110 are positioned within the deflection protection shield 29 to protect nearby property and personnel. To supply fluid to the pump chambers of the two pump assemblies, their inlet valves 46 are connected to a common pipe or inlet manifold 116, which has a knob T to a manual three-way valve 114 (FIGS. 1 and 4). It has a shape joint.

Also connected to the valve are two suction pipes 112, each of which is connected to a fluid supply container or bottle 12, 14. Said valve has three positions and is adapted to connect the manifold 116 by a corresponding suction pipe 112 to one or the other of the two bottles or to shut off the device. Each suction tube 112 has a vertical outer end portion of sufficient length to extend near the bottom of the bottle or container 12 or 14 to siphon all of the fluid within the container. Pivotally mounted on the vertical portion is a cap 113 adapted for sealing engagement with a conventional screw in the neck of the bottle. Note that each tube 112 has a rotary joint 1 near its inner end.
12' so that a filled bottle can be placed in the operative position and an empty bottle can be removed from that position. To install the bottle in place, unscrew and remove the regular cap on the bottle, then attach the tube 112.
rock forward to allow the vertical part of the tube to be inserted inside the bottle, lift the bottle along said tube and slide it into position on the platform 2r, and then slide the cap 113 on the container. Screw it onto its neck. This task can be done quickly and easily. There is therefore no need to transfer fluid from one container to another. Bottle caps can be removed in seconds, and the small neck diameter reduces the risk of contamination. Once in place, the bottle is resealed to prevent contamination. The fluid can therefore be supplied to the device in its original container in the most hygienic manner and without coming into contact with contaminants. It should be noted that an empty bottle 12 or 14 can be replaced with a filled bottle while the device is drawing suction from another bottle 14 or 12, so that continuous feeding can be achieved. An outlet valve 48 is likewise connected to a common outlet pipe or manifold 118 for discharging fluid from the pump chambers of the two pump assemblies, which manifold has a T to outlet pipe.
The outlet tube has a glyph fitting and extends to a flow meter 120 and further to a catalyst supply hose 15 to the spray gun 16.

Said tubes 116, 118 are designed for convenience and ease of construction, to protect components from damage and human exposure to the catalyst, and to provide an aesthetic appearance. The cast upper protective cover or header 119 for the two pump assemblies can be a simple plastic tube cast in place in an epoxy material.

The selection valve 114 is also cast in place within the cover 119 or is formed in part by the cover, as well as the suction pipe 1.
12 is also pivotally mounted within the cover and connected to the valve by a plastic tube. Note that the tube is a cast cover 11.
9 can be made with holes drilled or cast into the hole. In either case, suitable fittings are used to connect tube 116.
, 118 can be connected to the pump assembly, and the outlet 118 can be connected to a flow meter 120. The flow meter is safely housed within the shield 29 in the gap between the two cylinders. A groove 32 for holding the upper edge of the shield 29 in place is suitably cast into the lower edge of the cover 119. As shown in FIGS. 1 and 4, the delivery device 10 further includes a pneumatic control system to automatically perform the tasks and to adjust the pump assemblies 27, 28 as described below. It's summery.

Compressed air is supplied to pressure gauge 126 and line 123 through manual pressure regulator 124 from a source such as a plant air line. The compressed air flowing out from the pipe 123 is transferred to a pair of pipes 1
Downstroke air inlet of two air motors through 28
8 and through pipe 130 valve device 132, 1
Delivered on 34th. The tube 128 is not connected to a valve, so that compressed air is continuously supplied to the chambers 86, 87 of the air motor, moving said piston downward in its suction stroke. To drive the piston upwards, compressed air is supplied to the three-way push button valve 132 and from there to the push button valve 134. In the normal position of valve 132, air flows through this valve into central air inlet 133 in control valve 134. Preferably a spool type sword?
Valve 134 has an opening to a pair of supply and vent tubes 136 and has a pilot tube 138 at its end.
The two pipes 136 are respectively connected to two air motor air inlet connecting members 70, and the two pipes 138 are respectively connected to two pilot connecting members 72. The control valve 134 is configured such that when air pressure is supplied to one end of the spool from the foot of the pipe 138 and the pilot connection member 72, the spool moves to cut off the supply of compressed air to the inlet connection member 70 of the air motor. and the control valve 134 from the underside of the piston of the motor.
The valve is configured to vent air through the valve as shown on the left side of the valve in FIG.

At the same time, the control valve 134 begins supplying compressed air to the other air motor inlet connections 70, as shown on the right side of the valve in FIG. The above operation is reversed when air pressure is supplied to the other end of the spool from the other pilot tube 138 and connecting member 72. The pilot tube 138 may have a restriction orifice, if necessary, to further ensure valve operation. Depressing the push button valve 132 cuts off the compressed air supplied from the tube 130 and vents the air chamber 90 or 91 below the piston of the air motor which is not vented by the control valve 134 at this time. As mentioned above, for aesthetic purposes and to provide protection, the pushbutton valve 132, control valve 134 and tubes 123, 128, 130, 136, 1
38 are all contained within a monolithic epoxy material forming a bottom cover 140, which still partially includes the lower cylinder heads 62 of the two pump assemblies.
Now that the structure of the assembly has been explained, its operation will now be explained. 4 and 6, compressed air is emitted from its source and a pressure regulator 12 is shown.
4 to the required pressure, e.g. 0.703-7.031 kg/cm2 (10-100 kg/cm2).
If the compressed air is set to
, chambers 90 , 9 through the pedestal valve 134 and the connecting member 70 .
1, then the other one, piston set 5
2. Push down one of 74, then push up the other one. With the selection valve 114 in its open position, neither of the piston sets will draw fluid and the pistons will remain in their highest position. The pistons remain in this highest position even if the same pressure is supplied to chambers 86,87. The reason is that each piston 7
This is because the exposed area of 4 is larger in chambers 90 and 91 than in chambers 86 and 87. The three-way valve 114 is then switched from its open position to one of its on positions, allowing fluid to be drawn from the corresponding one of the containers 12,14.

When pushbutton 132 is held depressed for approximately 15 seconds to begin work as shown in FIGS.
ventilated through. Once the chambers 90, 91 are vented, the compressed air in the chambers 86, 87 will push down both sets of pistons 52, 74 and through the inlet valve 46 both pump chambers 40,
41 to suck the fluid. As shown in FIGS. 4 and 8, upon release of pushbutton 132, valve 134 assumes one of its two final positions such that compressed air is supplied to only one of chambers 90, 91. become.

Thus the piston sets 52, 74 of the assemblies 27, 28
only one of them is biased upward. When the apparatus is started, fluid is supplied through the outlet valve 48 of one pump assembly to fill the empty outlet tube 118 and gun hose 15 (FIG. 1). Once outlet tube 118 and hose 15 are filled and the fluid therein is fully pressurized, pistons 52, 74 cease upward movement and are held in place by the hydraulic locking mechanism. Releasing the hydraulic locking mechanism provides fluid to the gun when the gun is triggered. 4 and 9, assuming that both pump chambers 40, 41 are filled with fluid, when the spray gun 16 is triggered to the open position, one assembly, e.g. ) only one pair of pistons 74, 52 moves upward.

This is because the canopy valve 134 occupies one of its two final positions, thus supplying only one of the chambers, eg 90, with compressed air and venting the other chamber 91. Assembly 2
7's piston 52 rises, it supplies fluid to the gun through its outlet valve as long as the gun is triggered to the open position. Fluid is supplied to the gun at the same pressure as the compressed air within chamber 90. This is because the area of piston 74 in chamber 90 minus the area of the same piston in chamber 86 is equal to the area of pump piston 52. Air regulator 124 can therefore be set to determine the pressure of fluid supplied to the gun. By observing the flow meter 120 and adjusting the air pressure with the regulator, the proper flow rate of fluid to the gun can be easily set. Fluid flow continues until the gun is triggered off, and this flow is automatically resumed when the gun is triggered on.

As piston 74 nears the top of its upward stroke, as shown in FIG.
The upper end of the mandrel 94 is exposed, and compressed air flowing out of the chamber 90 flows into the hollow mandrel and is supplied to the pilot tube 138, causing the spool of the control valve 134 to move to the left;
The compressed air is shut off to the chamber 90 of the assembly 27, and the chamber is ventilated, and at the same time, the supply of compressed air to the chamber 91 of the assembly 28 is started to ventilate the chamber.

The feeding stroke of the pistons 52, 74 of the assembly 28 is therefore initiated. The head of air pressure previously created in chamber 90 causes the piston of assembly 27 to continue its upward movement until the pressure of the fluid supplied by the other assembly 28 is greater than the pressure of assembly 27. continues momentarily. When chamber 90 is subsequently vented, piston 52 of assembly 27;
74 descends due to the air pressure in chamber 86, thereby performing a suction stroke and filling pump chamber 40. As is clear from the explanation on the sphere and FIGS. 9 and 10,
The continuous pumping of one of the assemblies 27, 28 is automatic as long as the gun 16 is triggered open and spraying fluid, and the fluid is delivered at a substantially constant rate and pressure; Moreover, vibrations are kept to a minimum. This is the first
This is evident from the resultant pressure curve shown in FIG. In this figure, the output of pump assembly 2-7 is represented by a dotted line, and the output of pump assembly 28 is represented by a solid line. As shown, assembly 28 is stationary when assembly 27 is delivering fluid at full pressure. As the pistons of assembly 27 then approach their highest position, the pilot stem is exposed and the spool valve is moved to supply air to chamber 91 of assembly 28, which increases the outlet pressure. It occurs quickly and reaches full pressure at the same time that the pressure in assembly 27 begins to drop. The cycle repeats as the piston of assembly 28 nears the top of its stroke. Therefore, the pressure fluctuations when switching from one pump assembly to another of the device are very small. In fact, only a flicker of change was observed in the flow meter, and almost no fluctuation occurred in the spray gun. The fluid supply is therefore practically constant both in its flow rate and in its pressure. If necessary, the air regulator 124 can be connected to the flow meter 12.
It can be adjusted to obtain the desired flow rate as indicated by 0.

Releasing the trigger of the gun automatically stops pumping, and triggering the gun automatically resumes pumping. When the container 12 or 14 that is supplying fluid is near empty, the selector valve 114 can be turned to allow fluid from another container to be delivered to the pump inlet. This emptied container can be quickly and conveniently replaced so that a continuous source of supply can be maintained for the pump. When the system is to be shut down, the selection valve 114 is moved to its closed position and an empty stroke or two is performed to empty the assemblies 27, 28 of fluid. As shown in FIG. 11, if for some reason the fluid in one of the pump chambers acts violently and decomposes or explodes, the following situation will occur.

The high pressure generated within the chamber causes the piston assembly to move downwardly against the air pressure and shear pin 105, thereby releasing piston 52 for downward telescoping movement into piston 74. let This movement immediately relieves the pressure in the chamber by increasing its volume several times. As soon as the piston 52 passes through the safety port 110, the high pressure in the chamber causes the generated gas to pass through the port 110.
It is quickly and safely lowered by draining from 10. Gas exiting from safety port 110 is deflected by shield 29 to prevent the gas and/or catalyst from being sprayed onto the operator. A spring 31 is provided to hold the shield in place so that the shield flexes to absorb forces and redirect the gas and/or fluid, and when the shield is completely It is designed to prevent it from being blown away. The explosive force is therefore absorbed and quickly dissipated, and its negative effects can be minimized. The pump assembly is ruggedly constructed to absorb high pressure and explosive forces.
This, along with its pressure relief properties, is designed to absorb the explosive force and dissipate it safely, thus preventing the propagation of the explosion. Since the initial pressure and shock release occur in the manner described above, and the piston 74 of the assembly 28 is driven downwardly, the residual air within the pilot mandrel 96 and pilot tube 138 is compressed, displacing the spool of the valve 134; Air is thereby delivered to the underside of piston 74 of assembly 27, emptying chamber 40 of fluid.

At this time, the spool of valve 134 moves again, but the assembly 2
Since the upward stroke of piston 74 at 8 is not resisted, this piston is quickly driven to its highest position and the valve spool moves again. Since the piston of assembly 27 then does not have time to return to its lowest position, only a small portion of the normal flow is drawn into the chamber and is immediately expelled by reversing the spool of valve 134. This cycle continues until the pistons of both air motors come to a stop at the top of their stroke due to the air pressure in the air system equalizing. Continuing in a decreasing manner, the stoppage of the piston occurs within a very short time following an explosion or similar reaction. The force generated by the explosion is therefore quickly dissipated, the fluid in the pump chamber is quickly emptied and the pump stops working, reducing the propagation of the explosive reaction. If such an explosion were to occur, the resulting contamination would require replacement of all components exposed to the explosion, and possibly the entire delivery system 10; Can be safely controlled or processed. The cyclical safety effects of the delivery device as described above occur automatically in the event of other failures within the device. For example, if the fluid hose 15 connected to the spray gun breaks, the back pressure at the outlet valve of each piston chamber will be zero and each chamber will immediately evacuate fluid on its pressure or output stroke. The time required to evacuate one chamber is insufficient to completely fill the other chamber, and both pumps reduce the stroke of the piston until it stops at the top of its stroke. It operates while emptying the chamber and balancing the air pressure. In this manner, fluid flow is automatically stopped with virtually no loss of fluid and without creating a substantially hazardous condition. The time required to reach the pump stop condition can be adjusted within certain limits by adjusting the size of the piston chamber vent in valve 134. After repairing and converting the hose 15, or after making other suitable repairs, the pushbutton valve 132 need only be pressed to resume pumping. Another advantage of the present dispensing device is that if you forget to switch to a fluid-filled container before the container 12 or 14 you are using is empty, the pump assembly will shut down and disable it. It is important to inform the staff.

After one of the pump assemblies draws air into its pump chamber, its next pump stroke is completed before the other assembly completes its suction stroke. Such a condition occurs when the air or catalyst intake stroke becomes substantially longer than the air exhaust stroke. This is because air, unlike the catalyst, is compressible and is rapidly expelled into the outlet manifold before the other assemblies have completed their suction strokes, facilitating said automatic shutdown of the pump assembly. . The foregoing construction and mode of operation allow the delivery device of the present invention to handle low stability fluids in substantially complete safety. The possibility of contaminating the fluid is significantly reduced. There is no risk of contamination since the fluid is not exposed to or may mix with compressed air or other motor operating fluids. The fluid is then pressurized in very small quantities. The heat normally generated by the pressurizing action is quickly dissipated by materials having a relatively large mass, especially aluminum, which has a high thermal conductivity and a large exposed area. Mechanical shock to the fluid and misuse of the fluid is also avoided.
The risk of violent reactions, ie explosions, is therefore minimized. Even if an explosion were to occur despite these precautions, the explosion would be small.

The reason for this is that the amount of fluid to be pressurized is very small; the maximum amount of fluid in each chamber is about 56.7 grams (2 ounces), and a large amount of fluid, such as a dozen liters (several gallons), The explosion can then be controlled compared to conventional devices which are pressurized in a common container and therefore can react like a bomb. Furthermore, according to the present invention, means for controlling and dissipating the energy of the explosion can be provided within the device to reduce the energy to a controllable level and prevent injury to personnel and destruction of property. Although preferred embodiments of the present invention have been described above, it should be understood that the present invention can be modified in various ways within the scope of the claims.

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[Brief explanation of drawings]

FIG. 1 is a perspective view of a low stability fluid delivery device according to the present invention coupled to a multi-component spray gun. FIG. 2 is a rear view of the delivery device showing the attachment of the deflection safety shield to the device. FIG. 3 is a vertical cross-sectional view of one pump assembly taken along line 3--3 of FIG. FIG. 4 is a route diagram showing an air control device for the delivery device of FIG. 1. FIG. 5 is a perspective view of the header at the top or pump end of the device, the mouth of which is shown in dotted lines. FIG. 6 is a diagram showing the two pump assemblies in the starting position. FIG. 7 is a diagram showing two pump assemblies initially being filled with fluid. FIG. 8 is a diagram of one pump assembly undergoing a pump stroke. FIG. 9 is a diagram of one pump assembly being filled with fluid while another assembly is undergoing a pump stroke. FIG. 10 is a diagram showing the pump assembly supply pressure as a function of time. FIG. 11 is a diagram illustrating the operation of the pump assembly when an explosion occurs in one of the assemblies. In the figure, 10 is a fluid delivery device, 12 and 14 are containers, 15 is a hose, 16 is a spray gun, 18 is a hose, 20 is an air hose, 22 is a foundation, 24 is a central part, 26 is a leg, 27,
28 is the pump assembly, 2T is the platform, 29 is the shield, 31 is the spring, 32 is the groove, 36 is the main body, 38 is the cylinder, 40, 41 are the pump chambers, 42 is the cylinder head, 44 is the sealing ring, 46 is the inlet Valve, 48 is an outlet valve, 5
0 is a screw hole, 52 is a pump piston, 53 is a sealing ring, 56 is a skirt, 58 is an enlarged part, 60 is a motor cylinder, 62 is a cylinder head, 64 is a sealing ring, 6
6 and 67 are screw holes, 70 and 72 are connecting members, 74 is an air motor piston, 76 is a small diameter upper part, 78 is an upper surface, 80 is a large diameter part, 86 and 87 are upper motor chambers,
88 is a mouth, 90 and 91 are lower motor chambers, 92 is a lower surface, 94 is a recess, 96 is a central shaft, 98 is a sealing ring, 1
00 is the upper tip, 102 is the bottom surface, 104 is the top surface, 105
is a shear pin, 109 is a recess, 110 is a safety opening, 111
．． 113 is a mouth, 112 is a suction pipe, 112' is a rotary joint,
114 is a three-way valve, 116 is an inlet Roman manifold, 118 is an outlet manifold, 119 is a header, 120 is a flow meter, 12
3 is a pipe, 124 is a pressure regulator, 126 is a pressure gauge, 128
, 130 is a tube, 132 is a push button valve, 133 is a central air inlet, 134 is a control valve, 136 is a supply vent tube, 138
140 is a pilot tube, and 140 is a bottom cover.

Claims (1)

Claims: 1. A delivery device for delivering a low stability fluid from a container and maintaining the fluid in the container in a non-pressurized state, comprising: a small volume pump device having an inlet and an outlet;
an inlet tubing arrangement connecting an inlet of the pumping device to fluid in the container; and an inlet tubing device operatively connected to the pumping device to actuate the pumping device to draw fluid from the container into the pumping device and to A motor device and operation of the motor device for pressurizing fluid within the pumping device and at its outlet, such that no fluid in the container is pressurized and only a small amount of fluid is pressurized at any one time in succession. and a control device located between the motor device and the pump device, which prevents damage to either the motor device or the pump device if excessive pressure is generated in the pump device. a releasable connecting member for releasing the connection between the motor and the motor; the device is operatively connected to the piston by the releasable coupling member for reciprocating it within the cavity;
The releasable coupling member adjusts the movement of the piston into the adjacent chamber to reduce the volume of the pump chamber when excessive pressure is generated in the pump chamber and the pump device is uncoupled from the motor device. A delivery device characterized by increasing the pressure and decreasing the pressure therein. 2. The delivery device according to claim 1, wherein the releasable coupling member is a shearable member for disconnecting the motor device and the pump device, and the member is provided with A delivery device that shears to disconnect the pump device and the motor device when pressure is generated. 3. The delivery device according to claim 2, wherein the pump device includes a pair of reciprocating piston pumps, each of which has a cylinder defining a pump chamber of small volume, and a cylinder that defines a small volume pump chamber, and the piston pump. The pump device has a piston that reciprocates in a chamber, and an inlet valve and an outlet valve provided at an inlet and an outlet of the pump device, respectively, and the motor device has a pair of fluid pressure operated motors that can freely reciprocate. each motor includes a cylinder and a piston that reciprocates within the cylinder, defining with the cylinder a pair of fluid pressure chambers on opposite sides of the piston for moving the pistons in opposite directions; This piston of each motor has a
The control device is connected to a piston of each pump to cause the pump piston to reciprocate through a suction stroke and a discharge stroke, and the control device selects pressurized working fluid to a corresponding one of the motors at a time. a first valve arrangement configured to supply fluid pressure to the motor and cause the pump piston to perform a discharge stroke as a function of fluid pressure at the outlet of the pump; and actuating the first valve device when the respective motor piston approaches the end of the discharge stroke of the respective pump piston;
a second valve device configured to cut off the supply of working fluid to the discharge stroke side of each motor piston and to start supplying the working fluid to the discharge stroke side of the piston of the other motor; Thus, by keeping the source of low stability fluid unpressurized and pressurizing only a small amount of low stability fluid at any given time by only one pump piston, the low stability fluid at the outlet of said pump can be compressed. A delivery device that continuously pressurizes a stable fluid and automatically operates the delivery device as a function of the demand for the low stability fluid. 4. The delivery device of claim 3, wherein each of the pump cylinders has a length greater than the pump chamber and defines the adjacent chamber into which the pump piston enters; The chamber has at least one
the releasable coupling member is released when excessive fluid pressure is generated within the pump chamber, and the pump piston enters the adjacent chamber under the action of the pressure; a delivery device adapted to relieve said overpressure by exposing said pumping chamber, thereby increasing the volume of said pumping chamber containing said fluid, and venting said pumping chamber through said vent.