JP3482309B2 - Method and apparatus for foaming high viscosity material - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a device for foaming a high-viscosity material, and is used, for example, for a field-molded gasket, filling voids and the like.

[0002]

2. Description of the Related Art FIG. 10 is a fluid circuit diagram of a conventional high-viscosity material foaming apparatus 90. In FIG. 10, the high-viscosity material stored in the storage can 91 is pressure-fed by the primary pump 92 and fed into the power mixer 94.
The compressed gas filled in the tank 93 is sent to the power mixer 94 after the pressure is adjusted.

The power mixer 94 is rotationally driven by a motor M and agitates the fed high viscosity material and gas under high pressure. The high-viscosity material stirred by the power mixer 94 is discharged from the nozzle 96 via the pipe 95. As the gas, nitrogen gas, carbon dioxide gas, air or the like is used.
Such a foaming device 90 is used as a device for applying a high-viscosity polymer material such as a hot melt adhesive (Japanese Patent Laid-Open No. 63-264327).

The hot melt adhesive contains a thermoplastic polymer which is a solid at room temperature as a component, and melts and flows when heated. On the other hand, when the hot melt adhesive is melted by heating and then cooled to room temperature, it becomes solid, and the adhesive strength and the strength of the lump of the adhesive are exhibited.
Conventional foaming devices for such hot melt adhesives utilize the property of rapidly developing strength after cooling before the gas mixed in the hot melt adhesive is dissipated,
Incorporates gas to form a foam.

[0005]

However, in the above-described conventional foaming apparatus 90, the high-viscosity material and gas must be heated and sent to the power mixer 94 or the upstream thereof at high pressure. For example, when the viscosity of the high-viscosity material is 100,000 cps, the internal pressure of the power mixer 94 is 100 kg / cm.
^Since it is considered that the pressure is ² or more, in order to send the gas to the power mixer 94 at the same time as the high-viscosity material, it is necessary to make the pressure higher than the pressure of the high-viscosity material.

When the gas pressure is high, it is difficult to control the flow rate, and a slight error in the flow rate at high pressure appears as a large error at atmospheric pressure. For example, the error of the flow rate at 50 kg / cm ² becomes 50 times larger at atmospheric pressure. Therefore, a large variation occurs in the mixing ratio of the high-viscosity material and the gas, the foaming state becomes unstable, and it is extremely difficult to obtain uniform foaming.

The present invention has been made in view of the above-mentioned problems, and a gas can be mixed with a high-viscosity material at a low pressure,
The purpose of the present invention is to easily control the flow rate of gas, reduce variations in the mixing ratio of high-viscosity material and gas, stabilize the foaming state, and obtain uniform foaming.

That is, the present invention provides a method and an apparatus capable of easily mixing a gas into a high-viscosity material at a low pressure, especially at a low pressure of about atmospheric pressure, and easily obtaining a foam without using a power mixer. The purpose is to provide.

[0009]

[0010]

[0011]

[0012]

[0013]

[0014]

[0015]

[0016]

[0017]

SUMMARY OF THE INVENTION The method according to the present invention comprises a cylinder of a first piston pump interposed in a conduit for delivering a high viscosity material withdrawn by a first pump, said high viscosity material and gas. Is supplied to mix the gas into the high-viscosity material, and a mixture of the high-viscosity material and the gas delivered from the first step is pressurized by a second pump. The second step, the third step of dispersing the gas in the high-viscosity material by passing the pressurized mixture through the dispersing pipeline, and the passing of the dispersing pipeline. a fourth step of foaming by ejecting mixed-like material, was closed, the first
In the first step, the first piston pump cylinder
Supply the gas to the furnace, then supply the high viscosity material
To do.

According to a second aspect of the present invention, there is provided the method according to the first aspect.
A follower plate pump is used as the pump.

The method according to the invention of claim 3 is the first
The gas and the high-viscosity material are separately supplied to the cylinder of the piston pump of 1, and the gas is mixed into the high-viscosity material.

According to a fourth aspect of the present invention, there is provided the method according to the first aspect.
A plurality of piston pumps are used as the piston pump of. In the method according to the invention of claim 5 , in the first step, the mixing ratio of the gas supplied to the cylinder of the first piston pump and the high-viscosity material is controlled by the ratio of the supply pressures thereof.

A method according to a sixth aspect of the invention is the method of the first aspect.
In the step of, the supply amount of the gas to be supplied to the cylinder of the first piston pump and the supply amount of the high-viscosity material are set to the pressure of the high-viscosity material in the discharge pipe line of the fourth step and The mixing ratio of the high-viscosity material and the gas is controlled by controlling the density according to the density.

The method according to the invention of claim 7 uses carbon dioxide gas as the gas. In the method according to the invention of claim 8 , carbon dioxide gas and nitrogen gas are used together as the gas. In the method according to the invention of claim 9, air is used as the gas.
To use.

The method according to the invention of claim 10 uses a piston pump as the second pump. Claim 11
According to the method of the invention, in any one of the second step, the third step, and the fourth step, a static mixer is used, and the mixture is passed through the static mixer.

In the method according to the invention of claim 12 , in any one of the second step, the third step or the fourth step, a power mixer is used, and the mixed material is the power mixer. Let it pass.

In the method according to the invention of claim 13 , a pressure regulating valve is provided on the downstream side of the dispersion pipe, and the pressure of the mixture in the dispersion pipe is maintained at a predetermined pressure or higher. To do. In the method according to the invention of claim 14, an opening / closing valve is provided in the flow path of the mixture in the fourth step, and the second pump is operated in conjunction with the opening / closing valve to open the opening / closing valve. Sometimes the second pump is operated at a timing earlier than that.

[0026]

[0027]

[0028]

[0029]

The apparatus according to the present invention comprises a first pump for delivering high viscosity material, the high viscosity in order to mix the gas supplied from the gas supply device to the high-viscosity material fed from the first pump A first piston pump connected to the material line and the gas line, and the high viscosity material line.
And the first pipe connected to the gas pipeline.
The gas is supplied to the cylinder of the stone pump and then
For high viscosity materials that are controlled to supply high viscosity materials
Control valve and a control valve for gas, a second piston pump for pressurizing a mixture of the high-viscosity material and the gas delivered from the first piston pump, and the mixture in a pressurized state. It has a dispersion pipeline for dispersing the gas in the high-viscosity material by passing a substance, and a discharge device for discharging the mixed material that has passed through the dispersion pipeline.

In the apparatus according to the sixteenth aspect of the invention, a plurality of piston pumps are used as the first piston pump. The apparatus according to the invention of claim 17 is provided with a pressure adjusting valve for adjusting the pressure of the mixture in the dispersion pipe.

According to a eighteenth aspect of the present invention, there is provided an opening / closing valve which is provided on the downstream side of the dispersion pipe line to open and close the flow path, and the opening / closing valve when the pressurization by the second piston pump is stopped. When the valve is closed and the on-off valve is opened, the second piston pump is operated at a timing earlier than that to maintain the pressure of the mixture in the dispersion pipe in a pressurized state. And a maintenance control unit.

A device according to a nineteenth aspect of the present invention is a supply amount control device for controlling the supply amount of the gas, and a control drive for controlling the supply amount of the high-viscosity material of the first piston pump. Device, a measuring device for measuring the pressure and density of the high-viscosity material in the discharge device, and the high viscosity by giving a command to the supply amount control device and the control drive device based on the measured pressure and density. A foamed state control unit for controlling the foamed state of the material.

High-viscosity materials include adhesives, sealing materials for gap filling, coating materials, gasket materials for in-situ foaming, etc., moisture-curable materials, thermosetting materials, reaction-curable materials, hot-melt materials, etc. Is mentioned. In either case, in the method and apparatus of the present invention, it is desirable that the material be rapidly cured or solidified after discharge foaming, and it is cured or solidified in a state in which a gas is dispersed in a high-viscosity material.

As the gas, carbon dioxide gas, nitrogen gas, air or the like can be used. A uniaxial screw pump, a gear pump, a trochoid pump, a plunger pump, a follower pump, etc. are used as the first pump. A piston pump, a plunger pump, a gear pump, a trochoid pump, or the like is used as the pump or the second pump. A piston pump that can obtain a constant flow rate is used as the piston pump.

A long pipe of, for example, several meters to several tens of meters is used as a dispersing pipe for dispersing gas in a high-viscosity material. Such a pipe is wound, for example, in a straight line shape, an arc shape, or a spiral shape, and is used as a dispersion conduit unit attached to a frame for supporting it. The mixture of the high-viscosity material and the gas passes through the dispersing pipe under pressure, whereby the gas is atomized by the shearing force, and the atomized gas is dispersed in the high-viscosity material.

Carbon dioxide gas (carbon dioxide) is 70 k at 20 ° C.
When carbon dioxide gas is used as the gas, it is liquefied when a pressure of g / cm ² or more is applied. Therefore, by mixing carbon dioxide gas into the high-viscosity material at low pressure and then pressurizing it to high pressure, Carbon dioxide gas liquefies and at the same time dissolves in the highly viscous material. As a result, carbon dioxide gas is dispersed in the high-viscosity material. In addition, the control of the mixing ratio of the high-viscosity material and the gas can be performed accurately.

When carbon dioxide gas and nitrogen gas are used in combination, carbon dioxide gas is easily liquefied and nitrogen gas is difficult to liquefy.
Since the pressure for liquefying is different in this way, when the pressure is released and the pressure is returned to normal pressure, which is the opposite of the pressure applied, the vaporized nitrogen gas will explode uniformly and the nitrogen gas cavity (gas Carbon dioxide that vaporizes toward the nucleus tends to concentrate, and the effect of increasing the firing rate while maintaining the uniform foaming state can be obtained.

[0039]

1 is a circuit diagram of a foaming apparatus 1 according to the present invention, FIG. 2 is a sectional view showing a suction portion of a uniaxial screw pump 42, and FIG. 3 is a sectional view showing a main portion of a piston pump 51. 4 is a sectional view of the pipe unit 61 for dispersion.

The foaming device 1 comprises a compressed gas supply device 11 and a mixing device 1 provided corresponding to the first step of the present invention.
2, a pressure device 13 provided corresponding to the second step, a dispersion device 14 provided corresponding to the third step, a discharge device 15 provided corresponding to the fourth step, and these. It is composed of a control device 19 for controlling the whole.

The compressed gas supply device 11 comprises a tank 31, a pressure adjusting valve 32, a flow rate control device 33, a three-way valve 34, throttle valves 35 and 36, a check valve 37, and a pressure adjusting valve 38.

The tank 31 is filled with high-pressure nitrogen gas or carbon dioxide gas. Pressure adjusting valve 32 is 1 to 10 kg
/ Cm is set in the ² range of about, to maintain the pressure of the gas supplied from the tank 31 at a constant low pressure. When air is used as the gas, a compressor is used instead of the tank 31. The flow rate control device 33 measures the flow rate Qg of the gas, displays the measured value on the display 33a, and controls the flow rate of the gas based on the control signal S5 from the control device 19.

The three-way valve 34 is provided to reduce the control error of the flow rate control device 33 due to the difference in flow rate between when the gas is being supplied to the mixing device 12 and when the gas supply is stopped. The three-way valve 34 switches the flow path between the direction in which the gas is supplied to the mixing device 12 and the direction in which the gas is opened to the atmosphere. When supplying the gas to the mixing device 12, the gas is supplied via the three-way valve 34, and the mixing device 1
When the gas is not supplied to 2, the three-way valve 34 is switched and the gas is opened to the atmosphere. As a result, the differential pressure in the flow rate control device 33 during operation and non-operation of the mixing device 12 is made constant, the operation of the flow rate control device 33 is stabilized, and variations in the mixing ratio are suppressed.

A low pressure gas having a predetermined flow rate and a predetermined pressure is supplied to the mixing device 12 by the compressed gas supply device 11. The mixing device 12 supports a storage can 41 that stores the high-viscosity material MV, a uniaxial screw pump 42 as a first pump, a motor M1 that rotationally drives the uniaxial screw pump 42, the uniaxial screw pump 42, and the motor M1 so as to be vertically movable. In addition, the bottom of the uniaxial screw pump 42 is made of high-viscosity material MV.
It is composed of a cylinder device 43 to be pressed against and a pipe line 44. The high-viscosity material MV is, for example, 30,000 c
ps or more.

In FIG. 2, the uniaxial screw pump 42 has a stator 421, a rotor 422, a plate 423, etc., and a tip of a gas pipe 424 for supplying gas from the compressed gas supply device 11 to the suction port SP1. The portion 425 is open. When the rotor 422 is rotated by the motor M1, the high-viscosity material MV is sucked from the suction port SP1,
At the same time, the gas supplied from the tip portion 425 also enters from the suction port SP1 and is mixed into the high-viscosity material VM. As a result, inside the rotor 422, the high-viscosity material MV and the gas are transferred as a mixed material in a mixed state, and the mixed material is delivered to the pipe line 44. The delivery pressure to the pipeline 44 is 100 kg / cm ² or less, and usually 5
It is performed at 0 to 100 kg / cm ² . Inhalation port SP1
Since the pressure in the vicinity of is as low as about 1 kg / cm ² or less, the gas can be introduced into the uniaxial screw pump 42 at a low pressure. The rotation speed of the motor M1 is controlled by a signal S4 from the control device 19, and the flow rate (suction amount) of the uniaxial screw pump 42 is controlled by this.

In FIG. 3, the pressurizing device 13 includes a piston pump 51 as a second pump, and a piston pump 51.
Motor M2 for driving, on-off valves 52 and 53, pressure gauge 5
4, a pressure sensor 55, and the like.

The piston pump 51 is a cylinder 51
1, a piston 512, a packing 513, and the like. When the piston 512 moves upward while the on-off valve 52 is open and the on-off valve 53 is closed, the mixture of the high-viscosity material MV and the gas sent from the mixing device 12 is sucked into the cylinder 511. When the piston 512 moves downward with the open / close valve 52 closed and the open / close valve 53 open, the mixed material in the cylinder 511 is pushed out to be in a pressurized state. The pressure in the cylinder 511 is detected by the pressure sensor 55 and sent to the control device 19. The extrusion pressure from the piston pump 51 is 150 kg / cm ² or more. The pressure gauge 54 outputs a contact signal when detecting a preset pressure. The motor M2 is connected to the control device 19
The rotation speed is controlled by the signal S3 from the signal S3 from which the suction and the extrusion of the piston pump 51 and the flow rate (extrusion amount) thereof are controlled.

In FIG. 1, the dispersion device 14 comprises a dispersion pipe unit 61, pressure control valves 62 and 63, and a pressure gauge 6.
It is composed of 4, 65A and the like. In FIG. 4, the distribution line unit 61 includes the plates 6 arranged at both ends.
11, 612 are connected and fixed by rods 613, 613 ..., A spirally wound pipe 614 is mounted between the plates 611, 612, and each end of the pipe 611 is connected via a pipe member to the plate 611. , 612 are connected to ports 615 and 616, respectively. The pipe 614 corresponds to the dispersion conduit of the present invention. The pipe unit for dispersion may be a pipe having only a spiral shape.

The pipe 614 is made of steel, for example, and has a total length of, for example, 10 to 5 m when the nominal diameter is 3/8.
When the nominal diameter is 1/4, the total length is, for example, 10 to 2 m. The mixture of the high-viscosity material MV and the gas has, for example, a pressure of 150 kg / cm ² or more, for example, 200 to 250.
By passing through the pipe unit for dispersion 61 at a flow rate of 200 kg / cm ² and a flow rate of 200 cc / min, the gas becomes fine particles having an average diameter of, for example, about 0.01 mm and is dispersed in the high-viscosity material MV.

The phenomenon of gas dispersion is considered as follows. That is, in a conduit such as the pipe 614,
The gas flowing with the high-viscosity material MV is the high-viscosity material M
Since it has a remarkably smaller specific gravity and a lower viscosity than V, it moves toward the pipe wall with a slow flow velocity and is dispersed in the high viscosity material MV by the shearing force generated between the pipe wall and the high viscosity material MV. . Since the volume of gas is reduced by pressurization, the higher the pressure, the greater the dispersion effect. In other words, large bubbles first move towards the tube wall and are sheared into small bubbles. A mixture of highly viscous material MV in which the diameter of the bubbles has been made extremely small is a highly viscous material M
Since the difference in specific gravity and the difference in viscosity with only V become small, the phenomenon of returning to the central portion apart from the pipe wall occurs in the pipe passage. As the pressure in the conduit decreases, the volume of the bubble increases and the bubble moves to the wall of the tube where it is sheared again. This phenomenon is repeated, and the gas is sheared and dispersed in the high-viscosity material MV.

The phenomenon of gas dispersion can be estimated as follows. That is, when the mixture of the gas and the high-viscosity material is passed through the dispersion pipe under pressure, a pressure gradient occurs in the dispersion pipe due to the pressure loss generated toward the atmosphere side. The gas mass expands as the pressure decreases, but at the same time it expands and collapses and splits. In this way, the mass of gas mixed in the high-viscosity material is dispersed into fine bubbles (mass of gas) by continuously causing expansion and disintegration splitting in the dispersion conduit. A foam is obtained by discharging this into the atmosphere.

Therefore, the viscosity characteristic of the high-viscosity material MV,
The pressure inside the pipe 614, the pipe diameter, and the pipe length may be set according to the specific gravity and the required discharge amount. The pressure adjusting valves 62 and 63 are for maintaining the high-viscosity material MV in the pipe unit 61 for dispersion at a high pressure. For example, the pressure adjusting valve 62 has a pressure adjusting valve of 150 to 350 kg / cm ² or more. 63 is set to about 50 to 250 kg / cm ² .

Referring again to FIG. 1, the discharging device 15 is for returning the mixture of the high-viscosity material MV and the gas sent from the dispersing device 14 to the normal pressure and discharging it, thereby foaming. The discharge device 15 includes a discharge pipe 71, a discharge opening / closing valve 72, a nozzle 73, a densitometer 74, a pressure sensor 75, and the like.

The mixture sent from the dispersing device 14 is
By flowing through the discharge pipe 71, the pressure gradually returns to normal pressure, and the gas expands accordingly. Discharge on-off valve 72
When is open, a mixture of the high-viscosity material MV and gas is discharged from the nozzle 73, and foams when discharged.
By moving the nozzle 73 along a predetermined locus, the foamed high-viscosity material MV is applied or molded into a predetermined shape.

The densitometer 74 continuously measures the mass of the circulating high-viscosity material MV online, for example. Measurement signal S1 by the densitometer 74 and pressure sensor 75
The detection signal S2 according to is input to the control device 19.

The controller 19 calculates the expansion ratio A based on the measurement signal S1 and the detection signal S2, outputs the signals S3 to S5 so that the expansion ratio A becomes a predetermined value, and the gas flow rate Qg, and The suction amount of the uniaxial screw pump 42 is controlled. As a result, the entire foaming device 1 is controlled, and a series of processes for discharging the high-viscosity material VM so that the foaming ratio becomes a predetermined value is online-controlled. The expansion ratio A is defined by the following formula.

Expansion ratio A = V ₁ / V ₀ where V _{1 is} the volume per unit mass of the high viscosity material after foaming (when open to the atmosphere) V _{0 is} the volume expansion per unit mass of the high viscosity material before foaming In the apparatus 1, the expansion ratio A can be set within a range of, for example, about 1 to 4, and in the case of an in-situ foam molded gasket, it is usually set to an appropriate value within a range of 2 to 4.

According to the foaming apparatus 1 described above, the tank 31
The uniaxial screw pump 42 for the gas inside is at a low pressure of about atmospheric pressure.
Since it can be supplied to the suction port SP1 and mixed with the high-viscosity material MV, the mixing ratio can be controlled with high precision by controlling the gas flow rate Qg.
The foaming ratio A of V can be accurately controlled to obtain uniform foaming. Since the gas pressure is low, it is also possible to supply low-pressure compressed air, for example, by a compressor without using the high-pressure tank 31.

In the present invention, the mixture can be circulated through the dispersion conduit unit 61 under pressure so that the gas can be made finer and the dispersion efficiency can be improved. Since the pipe unit 61 for dispersion has a simple structure,
Maintenance is easy and cost can be reduced. It should be noted that the dispersion conduit unit 61 and an ordinary mixer such as a power mixer or a static mixer can be used together. These ordinary mixers may be provided in any of the second step, the third step, or the fourth step.

Next, a modification of the foaming device 1 will be described. FIG. 5 is a diagram showing a pressure device 13a, a dispersion device 14a, and a discharge device 15a in another example of the foaming device 1a, and FIG. 6 is a diagram showing operation timing of the foaming device 1a. 5, elements having the same functions as those in FIG. 1 are designated by the same reference numerals. The same applies hereinafter.

In this foaming device 1a, an opening / closing valve 65 is provided between the distribution pipe line unit 61 and the discharge pipe line 71a in place of the pressure adjusting valve 63. That is,
In the foaming device 1 described above, the pipe line unit 61 for dispersion is used.
The pressure adjusting valve 63 is provided to maintain the inside of the container at a predetermined pressure. However, in the foaming device 1a of this example, the discharge conduit 71 is provided.
The diameter of a is reduced to increase the conduit resistance, and the opening / closing timing of the on-off valve 65 is controlled appropriately so that a predetermined pressure is generated and maintained inside the dispersion conduit unit 61. Is.

In FIGS. 5 and 6, the pressure sensor 55
Detects the pushing pressure of the piston pump 51,
Outputs a signal S6 when the detected pressure becomes the set pressure (150~350kg / cm ²⁾ or more, and outputs a danger signal S7 is the case where the maximum allowable pressure 400 kg / cm ² or more devices. The extrusion signal is a signal for instructing the extrusion of the high-viscosity material VM, and while the extrusion signal is on, when the discharge is possible, the on-off valves 65 and 72 are opened to discharge the high-viscosity material MV. Foam. While the high-viscosity material MV is being extruded, pressure is generated by the conduit resistance of the discharge conduit 71a, and a predetermined high pressure is generated inside the dispersion conduit unit 61. Even if the push signal is on, the piston pump 51 automatically switches to the suction process when the bottom dead center signal of the end position in the push process is output by the proximity sensor attached to the piston pump 51. In addition, since the discharge is not possible during the suction process, the open / close valves 65 and 72 are closed. When the signal S7 is output from the pressure sensor 55, it is determined that an abnormality such as clogging of the pipe has occurred, an emergency stop is performed, and an alarm is output. When the push signal turns off,
The open / close valves 53, 65, 72 are closed, the open / close valve 52 is opened, and the piston pump 51 performs the suction process.
With the open / close valves 65 and 72 kept closed, the open / close valve 53 is opened, the open / close valve 52 is closed, and the piston pump 51 performs the extrusion process for a short time. As a result, the high-viscosity material MV is extruded, and the signal S6 of the pressure sensor 55 is output. After that, the on-off valves 52, 53, 65, 72 maintain their previous states, the piston pump 51 is stopped, and the standby state is established. It becomes a state. In the standby state, the inside of the dispersing pipeline unit 61 is maintained at a predetermined pressure state, and when the discharge signal is turned on next and the piston pump 51 performs the extrusion process, the inside of the dispersing pipeline unit 61 is The pressure is maintained continuously without any pressure drop. As a result, the dispersion of the gas by the dispersion conduit unit 61 is always performed normally.

In the foaming apparatus 1a, the pressure adjusting valve 63 is unnecessary, so that the cost can be reduced accordingly. FIG. 7: is a figure which shows the foaming apparatus 1b of another example. In the foaming device 1b, a curing agent supply device 16 is provided to use a two-component curing type high-viscosity material.
The curing agent supply device 16 injects and mixes the curing agent MS into the high-viscosity material MV at the tip portion of the discharge conduit 71b. A manifold 76 having a built-in check valve is connected to the tip of the discharge pipe line 71b. The injected curing agent MS merges with the high-viscosity material MV in the manifold 76, is sufficiently mixed by the power mixer or the static mixer 77, and is discharged.

The hardener supply device 16 is composed of a supply pipe 86, a flow meter, open / close valves 88, 89 and the like. The hardening agent MS in the hardening agent tank 82 flows into the manifold 76 through the supply pipe line 86, and joins with the high-viscosity material MV there. Since the amounts of the high-viscosity material MV and the curing agent MS are determined by the operating states of the piston pump 51 and the curing agent pump 83, respectively, their mixing ratio can be freely set.

According to the foaming device 1b, since the two-component curing type high-viscosity material MV can be used, the curing speed can be increased. Since the curing agent MS is merged at the tip portion of the discharge conduit 71b, the portion to be cleaned can be reduced.

In the foaming apparatus 1b shown in FIG. 7, the high-viscosity material MV which is the main component is foamed.
High-viscosity material MV and hardener MS are replaced with hardener MS
May be foamed. In addition, high viscosity material MV
Both the hardener MS and the hardener MS may be foamed.

Next, the case where carbon dioxide gas is used as the gas will be described. Since carbon dioxide is in a gaseous state under low pressure and easily becomes a liquid under high pressure (20 ° C., 70 kg / cm ² ), when the gas is mixed with a high-viscosity material, it is easy to control the flow rate of the gas. It is possible to accurately control the mixing ratio of the viscous material and the gas, stabilize the foaming state, and obtain a uniform foam.

In the foaming device 1 shown in FIG. 1, the tank 31 of the compressed gas supply device 11 is filled with high-pressure carbon dioxide gas. The pressure adjusting valve 32 is set to a pressure of 10 kg / cm ² or less, for example, about 7 kg / cm ² , and the tank 31
The pressure of carbon dioxide gas supplied from is maintained at a constant low pressure.

The low pressure carbon dioxide gas having a predetermined flow rate and a predetermined pressure is supplied to the mixing device 12 by the compressed gas supply device 11. By the mixing device 12, the high-viscosity material MV and carbon dioxide are mixed and transferred as a mixed state,
It is delivered to the pipeline 44. The delivery pressure to the pipeline 44 is, for example, about 50 kg / cm ² . This mixture is supplied to the pressure device 13.

The mixture is pressurized to a high pressure by the pressure device 13, and carbon dioxide gas in the mixture is liquefied and dissolved in the high-viscosity material MV. Carbon dioxide gas (liquefied gas) dissolved in the high-viscosity material MV easily disperses in a pipe or the like.

The extrusion pressure from the piston pump 51 of the pressurizing device 13 is 100 kg / cm ² or more, for example 150 to
The pressure is set in the range of 300 kg / cm ² . This set pressure is adjusted by, for example, the pressure adjusting valve 62.

The discharging device 15 returns the mixture of the high-viscosity material MV and the gas sent from the pressurizing device 13 to normal pressure and discharges it, and vaporizes the liquefied carbon dioxide gas to obtain a foam. As the gas, carbon dioxide gas that is easily liquefied under high pressure,
When using nitrogen gas, which is in the gaseous state at the pressure of liquefying carbon dioxide, the carbon dioxide gas liquefied under pressure vaporizes and concentrates in the gaseous nitrogen gas dispersed in the high-viscosity material with a slight delay. Since the cells are expanded, the expansion ratio can be increased.

FIG. 8 is a view showing a foaming device 1c of still another example. The foaming device 1c and the foaming method by the foaming device 1c correspond to the present invention. In the foaming device 1c shown in FIG. 8, the pressure device 13 in the second step and the dispersing device 14 in the third process of the foaming device 1 shown in FIG. 1 are not shown.

In the foaming apparatus 1c shown in FIG. 8, a follower plate pump 42A for feeding high-viscosity material is used as the first pump for delivering high-viscosity material, and the high-viscosity material sent from the follower plate pump 42A is used. Two piston pumps 45A and 45B are used as the first piston pump for mixing gas into the material.

The follower plate pump 42A sends the high-viscosity material stored in the storage canister to the pipe 39A by pressure-feeding the high-viscosity material by the plate. The piston pumps 45A and 45B are interposed between the conduit 39A and the conduit 44A, and are connected to the follower plate pump 4
The gas delivered from the tank 31A is mixed with the high-viscosity material delivered from 2A.

The capacity of the cylinder of the piston pump 45A, 45B is determined by the moving distance of the piston. In the suction process of each piston pump 45A, 45B, first, in each cylinder, from the tank 31A, until the gas reaches a predetermined amount corresponding to the capacity of the cylinder, 10 kg /
It is supplied at a pressure of not more than cm ² . Next, the high-viscosity material is supplied into the cylinder filled with gas from the follower plate pump 42A at a predetermined pressure of 10 kg / cm ² or more. At this time, the ratio between the pressure of the gas and the pressure of the high-viscosity material corresponds to the mixing ratio of the gas and the high-viscosity material. Therefore, it is easy to control the mixing ratio of these.

The pressure of the high-viscosity material to be supplied to the piston pumps 45A and 45B is adjusted by a control valve (for example, a piston valve) provided in the conduit 39A while keeping the follower plate pump 42A in a pressure-feeding state.

The pressure of the gas supplied to the piston pumps 45A and 45B is adjusted by the pressure adjusting valve provided in the gas conduit 39B. Especially, the pressure of this gas is piston pumps 45A, 45B even if it is normal pressure without pressurizing.
However, in this embodiment, the pressure is adjusted to a constant pressure of 10 kg / cm ² or less before use.

Gas and high-viscosity material are used for each piston pump 4
After the suction into the cylinders of 5A and 45B is completed, the discharge process is started. In the discharge process of each piston pump 45A, 45B, the mixture of the gas and the high-viscosity material passes through the flow control valve such as the piston valve or the check valve provided in the discharge-side conduit 44A, and the second piston It is sent to a piston pump 51 (see FIG. 1) which is a pump. By keeping the volumes (volumes) of the piston pumps 45A and 45B as small as possible, the amounts of the high-viscosity material MV and the gas delivered in one discharge process are reduced, resulting in a discontinuous and pulsed state. . By doing so, the dispersion in the subsequent dispersion step is performed better.

The mixed material is sent out from the piston pump 51 to the pipe 614 which is a pipe for dispersion, and by passing through the pipe 614, dispersion, that is, gas is dissolved in the high-viscosity material and mixed.

As shown in FIG. 8, by using two piston pumps 45A and 45B as the first piston pump, the discharge amount from the first piston pump can be increased and the continuous fixed amount discharge can be achieved. It can be carried out. Also, three or more piston pumps may be used instead of two. The plurality of piston pumps may be operated alternately or with a time difference. When two piston pumps are used, continuous discharge can be achieved by increasing the operating speed of the suction process with respect to the operating speed of the discharge process.

In the foaming apparatus 1c shown in FIG. 8, there are two operation modes, an alternate operation mode in which the two piston pumps 45A and 45B are alternately operated and an independent operation mode in which only one piston pump is independently operated. It is possible to switch and use these operation modes.

FIG. 9 is a diagram showing the timing of the operating state when the two piston pumps 45A and 45B are used as the first piston pump in the operation mode in which they are alternately operated.

In FIG. 9, piston pumps 45A, 4
The control timing of 5B is linked with the suction signal of the second piston pump for pressurization. In this specification and drawings, the piston pump 45A may be referred to as the pump 1 and the piston pump 45B may be referred to as the pump 2.

During the first discharge process in which the piston of the one piston pump 45A descends, the piston of the other piston pump 45B waits at the top dead center in the state of sucking the gas and the high viscosity material. When the piston of one piston pump 45A reaches the bottom dead center and the discharge is completed, the piston of the other piston pump 45B descends to perform the discharge process.

Next, while the other piston pump 45B is performing the discharging process, the one piston pump 45A sucks the gas and the high-viscosity material and stands by for the next discharging process.

The control valves for supplying the gas and the high-viscosity material to the piston pumps 45A and 45B are opened and closed according to the set time of the timer. For example, while the piston pump 45A is in the suction process and the piston is moving upward, the gas control valve V3 is turned on for the set time. During this time gas is fed into the cylinder. When the set time has elapsed, the control valve V3 is turned off, and the control valve V1 for high viscosity material is
Turns on. When the control valve V1 is turned on, the high viscosity material is supplied to the cylinder.

Similarly, the piston pump 45B is in the suction process, and the control valve V4 for gas is turned on while the piston is moving upward. Control valve V2 for high viscosity materials after gas is fed into the cylinder
Is turned on, and the high viscosity material is supplied to the cylinder.
The set time of the timer is determined according to the viscosity of the high viscosity material.

As described above, one piston pump 45A
When the piston discharge process is completed, the other piston pump 45B starts the discharge process, and thereafter, the discharge process is alternately performed. As a result, the mixed material is continuously discharged from the first piston pump.

In the above foaming devices 1, 1a, 1b, 1c, a gear pump, a trochoid pump, etc. may be used instead of the uniaxial screw pump 42. Piston pump 51
Instead of this, a gear pump, a plunger pump or the like may be used. The conduit unit 61 for dispersion may be used together with a power mixer or a static mixer. Foaming device 1,
The configuration, shape, size, material, quantity, operation timing, etc. of each part or the whole of 1a, 1b, 1c or the dispersion device 14 and the like can be appropriately changed other than those described above in accordance with the gist of the present invention.

[0091]

EXAMPLES Next, experimental examples using the foaming apparatus 1c will be described. (Example 1) As a high-viscosity material MV, a moisture-curable urethane-based sealing material (RD-4 manufactured by Sunstar Giken Co., Ltd.)
161), the viscosity of 200,000 cps was used, carbon dioxide gas and nitrogen gas were used as the gas, and the flow rate Qg of the gas was variously changed and the experiment was conducted. The experimental results are shown in Table 1.

[0092]

[Table 1]

It can be seen from Table 1 that by using carbon dioxide gas as the gas, very uniform foaming was obtained at a high expansion ratio. When the foaming state is evaluated under the same conditions using carbon dioxide gas and nitrogen gas, carbon dioxide gas is easily liquefied at high pressure even if the gas is supplied at low pressure to control the flow rate. It can be dissolved and mixed at a ratio of accuracy, and a high expansion ratio A can be obtained. (Example 2) As the high-viscosity material MV, a thermosetting urethane-based sealing material (manufactured by Sunstar Giken Co., Ltd.) was used,
An experiment was conducted in the same manner as in Example 1 using carbon dioxide gas and nitrogen gas as the gas. Carbon dioxide supply pressure is 7 kg / c
m ² , the gas flow rate Qg was 0.22 NL / min, and the pressurization pressure was 280 kg / cm ² . An experiment was also conducted on an example using a moisture-curable room-temperature-curable urethane as the high-viscosity material MV, which was set as Experimental Example 7. The experimental results are shown in Table 2.

[0094]

[Table 2]

According to Table 2, it is understood that the thermosetting high-viscosity material MV which is rapidly cured at a relatively low temperature gave a stable expansion ratio A. That is, normally, the expansion ratio A
In a high foam, the gas inside escapes to the atmosphere during the curing process of the material, and the expansion ratio A is significantly reduced. Since the gas can be retained by increasing the curing speed, a foam having a high expansion ratio A can be obtained.

[0096]

According to the present invention, the gas can be mixed with the high-viscosity material at a low pressure and with a simple structure, the flow rate of the gas can be easily controlled, and the variation of the mixing ratio of the high-viscosity material and the gas can be achieved. By reducing the amount, it is possible to stabilize the foaming state and obtain uniform and fine foaming. Since the high-viscosity material and the gas are not mixed with the power mixer or the gear pump as in the conventional case, the equipment can be simply configured with a simple and inexpensive device. The high-viscosity material does not generate heat due to frictional heat and adversely affects the foam.

According to the thirteenth and seventeenth aspects of the present invention, the inside of the dispersion pipe can be more reliably maintained at a high pressure, and the gas dispersion becomes more stable.

According to the inventions of claims 16 to 19 , the gas can be dispersed in the high-viscosity material with a simple structure, and the high-viscosity material can be stably foamed.
It

[Brief description of drawings]

FIG. 1 is a circuit diagram of a foaming device according to the present invention.

FIG. 2 is a sectional view showing a suction portion of a uniaxial screw pump.

FIG. 3 is a sectional view showing a main part of a piston pump.

FIG. 4 is a cross-sectional view of a dispersion conduit unit.

FIG. 5 is a circuit diagram of a part of another example of the foaming device.

6 is a diagram showing an operation timing of the foaming device of FIG.

FIG. 7 is a circuit diagram of a part of a foaming device of still another example.

FIG. 8 is a circuit diagram of a part of a foaming device of still another example.

9 is a diagram showing an operation timing in the alternate operation mode of the foaming device of FIG.

FIG. 10 is a fluid circuit diagram of a conventional foaming device.

[Explanation of symbols]

1, 1a, 1b, 1c Foaming device 16 Curing agent supply device 19 Control device (pressure maintenance control unit, foaming state control unit, control drive device) 33 Flow rate control device 39A Pipe line 42 Single screw pump (first pump) 42A Follower Plate pump (first pump) 44, 44A Pipes 45A, 45B Piston pump (first piston pump) 51 Piston pump (pump, second pump, second piston pump) 61 Dispersion pipe unit 63 Pressure Adjustment valve 65 Open / close valve 71, 71a, 71b Discharge pipe line (discharge device) 73 Nozzle (discharge device) 74 Density meter (measurement device) 75 Pressure sensor (measurement device) 76 Manifold (mixing device) 614 Pipe (dispersion pipe) Road) M1 motor (control drive device) VM high viscosity material MS curing agent

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI B05D 3/00 B05D 3/00 D (56) References JP-A-6-198152 (JP, A) JP-A-50-159871 ( JP, A) JP 63-264327 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B05B ⁷ /00-7/32 B05C 5/00 B05D 1/02 B05D 3 / 00

Claims (19)

(57) [Claims] 1. A high-viscosity material and a gas are supplied to a cylinder of a first piston pump interposed in a conduit for delivering a high-viscosity material extracted by a first pump, and the high-viscosity material is supplied to the cylinder. A first step of mixing a gas; a second step of pressurizing a mixture of the high-viscosity material and the gas delivered from the first step by a second pump; A third step of dispersing the gas in the high-viscosity material by passing the mixed material through the dispersing conduit, and foaming by discharging the mixed material that has passed through the dispersing conduit. and fourth step, the possess, in the first step, the first piston pump
Supplying the gas to a cylinder and then the high viscosity material
The method for foaming a high-viscosity material, comprising: 2. A use of follower plate pump as said first pump, foaming process highly viscous material according to claim 1, wherein 3. The gas and the high-viscosity material are separately supplied to a cylinder of the first piston pump,
The method for foaming a high-viscosity material according to claim 1 , wherein the gas is mixed with the high-viscosity material. 4. using a plurality of piston pumps as the first piston pump, foaming method of the high viscosity material according to any one of claims 1 to 3. 5. The mixing ratio of the gas and the high-viscosity material supplied to the cylinder of the first piston pump is controlled in the first step by controlling the mixing ratio thereof. Item 5. A method for foaming a high-viscosity material according to any one of Items 4 . 6. The supply amount of the gas supplied to the cylinder of the first piston pump and the supply amount of the high-viscosity material in the first step in the discharge pipe line of the fourth step. by controlling each in accordance with the pressure and density of the high-viscosity material in the controls the mixing ratio between said gas said high viscosity material, high viscosity material according to any one of claims 1 to 5 Foaming method. 7. using carbon dioxide gas as the gas, the foaming process of highly viscous material according to any one of claims 1 to 6. 8. used in combination carbonic acid gas and nitrogen gas as said gas, the foaming process of highly viscous material according to any one of claims 1 to 7. 9. The high-viscosity material according to claim 1 , wherein air is used as the gas .
Foaming method. 10. use of a piston pump as the second pump, foaming process of a high viscosity material according to any one of claims 1 to 9. 11. The static mixer is used in any one of the second step, the third step, and the fourth step, and the mixed material is allowed to pass through the static mixer. The method for foaming a high-viscosity material according to any one of claims 1 to 10 . 12. A power mixer is used in any one of the second step, the third step, and the fourth step, and the mixture is allowed to pass through the power mixer. The method for foaming a high-viscosity material according to any one of claims 1 to 10 . 13. The pressure regulating valve located downstream of the dispersing pipe, the pressure of the mixed form of dispersing pipe path is maintained to be equal to or greater than the predetermined pressure, claims 1 to 13. The method for foaming a high-viscosity material according to any of 12 . 14. An opening / closing valve is provided in a flow path of the mixed material in the fourth step, the second pump is operated in conjunction with the opening / closing valve, and the opening / closing valve is opened earlier than that. actuating the second pump at the timing, the foaming method of the high viscosity material according to any one of claims 1 to 13. 15. A first pump for delivering a high-viscosity material, and a gas supply for the high-viscosity material delivered from the first pump.
High viscosity material to mix the gas supplied from the equipment
Piston pump connected to the gas pipeline and the gas pipeline, and the high viscosity material pipeline and the gas pipeline, respectively.
Is inserted in front of the cylinder of the first piston pump.
To supply the gas and then the high viscosity material
Control valves for controlled high viscosity materials and controls for gases
A control valve, a second piston pump for pressurizing the mixture of the high-viscosity material and the gas delivered from the first piston pump, and the passage of the mixture under pressurization A foaming apparatus for a high-viscosity material, comprising: a dispersion conduit for dispersing a gas in the high-viscosity material; and a discharge device for discharging the mixture that has passed through the dispersion conduit. 16. The foaming apparatus for high viscosity material according to claim 15 , wherein a plurality of piston pumps are used as the first piston pump. 17. The foaming device for high-viscosity material according to claim 15 or 16 , further comprising a pressure adjusting valve for adjusting the pressure of the mixture in the dispersing pipe. 18. An on-off valve which is provided on the downstream side of the dispersing pipe and which opens and closes a flow path, and which closes the on-off valve when stopping the pressurization by the second piston pump. A pressure maintaining control unit for maintaining the pressure of the mixture in the dispersion pipe line in a pressurized state by operating the second piston pump at an earlier timing when opening. Item 18. A foaming device for a high-viscosity material according to any one of items 15 to 17 . 19. A supply amount control device for controlling the supply amount of the gas; a control drive device for controlling the supply amount of the high-viscosity material of the first piston pump; A measuring device that measures the pressure and density of the high-viscosity material, and a foaming device that gives a command to the supply amount control device and the control drive device based on the measured pressure and density to control the foaming state of the high-viscosity material. foaming device with a high viscosity material according to any one of claims 15 to 18 has a state control unit.