JP5255380B2 - Polyurethane foam production equipment - Google Patents

Description

  The present invention relates to a polyurethane foam manufacturing apparatus, and more particularly to a polyurethane foam manufacturing apparatus suitable for foaming polyurethane foam using liquid carbon dioxide (including a supercritical state, a subcritical state, or a liquid state) as a foaming agent.

  Conventionally, polyurethane foam has been widely used as a heat insulating board, a heat insulating material by spraying, a filling agent, and the like. Such a polyurethane foam usually uses a raw material liquid containing a polyisocyanate component, an active hydrogen group-containing compound component, and a foaming agent. It is manufactured by being discharged from and reacting and solidifying while the foaming limited amount of foaming is foamed.

  However, in recent years, many foaming agents such as Freon are being regulated as foaming agents for polyurethane foam due to problems such as ozone layer destruction, and methods using carbon dioxide as the foaming agent are being studied. When carbon dioxide is used as a blowing agent, it is necessary to use liquefied carbon dioxide (hereinafter referred to as liquefied carbon dioxide) and supply a predetermined amount thereof, but liquefied carbon dioxide has a critical point of about 31 ° C., about It is 7 MPa, and tends to be a gas at room temperature. For this reason, when liquefied carbon dioxide is to be metered and pumped from a carbon dioxide storage container such as a cylinder by a pump, there is a problem in that a predetermined amount cannot be pumped because gaseous carbon dioxide is mixed into the liquefied carbon dioxide. In particular, since the pressure tends to decrease on the suction side of the pump, there is a problem that carbon dioxide, which has become even more gaseous, is mixed into the liquefied carbon dioxide and a predetermined amount cannot be pumped.

  For this reason, various ideas for supplying a predetermined amount of liquid carbon dioxide without vaporization have been proposed.

For example, in Patent Document 1, a pressurized gas container is provided, and a pressurized gas is supplied from the pressurized gas container to the liquefied carbon dioxide container and pressurized to hold the liquefied carbon dioxide as a liquid. Patent Document 2 discloses a technique for keeping the temperature of liquefied carbon dioxide low and preventing vaporization of liquefied carbon dioxide introduced into the first liquefied carbon dioxide metering pump and the second liquefied carbon dioxide metering pump. ing. Patent Document 3 discloses that a chiller that adjusts the temperature of the refrigerant includes a refrigerant and a heat transfer tube that cools the refrigerant, and a liquefied carbon dioxide transfer channel is provided in the chiller. .
JP 2006-192720 A Japanese Patent Laid-Open No. 2005-200484 JP 2006-29895 A

  However, all of the urethane foam manufacturing apparatuses disclosed in the above patent documents measure and supply the amount of carbon dioxide supplied using a carbon dioxide metering pump, and a pump for supplying carbon dioxide is essential. And That is, the problem of vaporization of liquefied carbon dioxide is caused by the use of a pump for measuring carbon dioxide. As long as the pump is used, the problem of vaporization of liquefied carbon dioxide occurs. For this reason, in order to solve the problem as much as possible, in the urethane foam manufacturing apparatus disclosed in each of the above patent documents, a heat exchanger such as a chiller and a distribution pipe should be insulated to keep the temperature of liquefied carbon dioxide low. Alternatively, the pressure is increased using a pressurized gas container to prevent vaporization.

  Even if the liquefied state can be maintained in the vicinity of the liquefied carbon dioxide container, as long as the carbon dioxide is metered using the pump, the pressure tends to decrease during the suction process on the suction side of the pump, and the liquefied carbon dioxide is vaporized. It is not a drastic solution to the above problem of being easily converted. In addition, since the number of members such as a pressurized container and a heat exchanger increases, the apparatus becomes large and complicated.

  In view of the above problems, the present applicant has applied for a polyurethane foam manufacturing apparatus that can supply liquefied carbon dioxide without using a pump (Japanese Patent Application Nos. 2007-172295 and 2007-257622). . In this polyurethane foam manufacturing apparatus, liquefied carbon dioxide can be supplied without using a pump, so that the problem of vaporization can be solved. Moreover, in the said apparatus, an on-off valve is used as a supply means of the appropriate quantity of liquefied carbon dioxide, and an exact quantity of carbon dioxide can be supplied by controlling the timing of opening and closing.

  Therefore, in view of the above problems, the technical problem to be solved by the present invention is to solve the problem of vaporization of carbon dioxide by using a pump and to supply a more accurate appropriate amount of liquefied carbon dioxide. An object of the present invention is to provide a polyurethane foam manufacturing apparatus and a manufacturing method thereof.

  In order to solve the above technical problem, the present invention provides a polyurethane foam manufacturing apparatus having the following configuration.

According to the first aspect of the present invention, a polyurethane foam is produced by mixing and discharging the liquid A mainly composed of polyisocyanate, the liquid B, and liquefied carbon dioxide as a blowing agent supplied from a liquefied carbon dioxide container. A device,
A supply pump that sends out a liquid A mainly composed of polyisocyanate and a liquid B mainly composed of polyol so as to have a predetermined discharge pressure;
Liquefied carbon dioxide provided in the middle of a supply pipe for supplying liquefied carbon dioxide as a blowing agent supplied from a liquefied carbon dioxide container to the liquid A and / or liquid B and fed through the supply pipe An on-off valve that switches between feeding and stopping
In order to control the supply amount of the liquefied carbon dioxide, comprising a valve control means for switching the opening and closing of the on-off valve in conjunction with the supply pump so that the on-off valve is opened when the supply pump is driven,
The valve control means includes
A movable member of the supply pump and a detection member provided in a fixed state with respect to the movable portion of the supply pump, and a detection member for detecting a drive of the detected member and transmitting a pump operation signal; ,
An apparatus for manufacturing polyurethane foam, comprising: an operation control unit that switches between opening and closing of the on-off valve according to presence or absence of detection of a pump operation signal transmitted from the detection member.

  According to the second aspect of the present invention, when the operation control unit detects the pump operation signal to change the open / close valve from the closed state to the open state and does not detect the pump operation signal again within a predetermined time. An apparatus for producing a polyurethane foam according to a first aspect, wherein the polyurethane foam manufacturing apparatus is changed from an open state to a closed state, is provided.

According to a third aspect of the present invention, the supply pump includes a piston that sends out the liquid A and the liquid B by reciprocation,
The polyurethane foam manufacturing apparatus according to the first or second aspect is characterized in that the detected members are arranged along an operation direction of the piston.

According to the fourth aspect of the present invention, the detection member is constituted by a switch that transmits the pump operation signal when the detection member is pressed to be pressed.
The said to-be-detected member is comprised by the press member which presses the said switch, The polyurethane foam manufacturing apparatus of any one of the 1st to 3rd aspect characterized by the above-mentioned is provided.

According to a fifth aspect of the present invention, the valve control means is
A timer unit that counts an elapsed time after detecting the pump operation signal;
When the operation control unit detects the pump operation signal when the on-off valve is in the closed state, the operation control unit switches the on-off valve from the closed state to the open state, and when a predetermined time elapses without detecting the pump operation signal again. A polyurethane foam manufacturing apparatus according to a third or fourth aspect is provided, wherein the on-off valve is controlled to be in a closed state.

According to a sixth aspect of the present invention, the operation control unit is
When the pump operation signal is detected when the on-off valve is in the closed state, the on-off valve is switched from the closed state to the open state, and when the pump operation signal is detected again before the predetermined time has elapsed, the on-off valve is maintained in the open state. The polyurethane foam according to the fifth aspect, wherein the count of the timer unit is reset and the on-off valve is changed from the open state to the closed state when the pump operation signal is not detected again before a predetermined time elapses. Providing manufacturing equipment.

According to a seventh aspect of the present invention, the supply pump is
A pressing member holding member that extends in the driving direction of the piston and has a mounting region having the same dimensions as the stroke width of the piston;
The pressing member is arranged with an equal interval in an attachment region of the pressing member holding member,
A polyurethane foam production apparatus according to the first aspect is provided.

  According to an eighth aspect of the present invention, there is provided the polyurethane foam manufacturing apparatus according to any one of the seventh aspect, wherein the attachment region of the pressing member holding member is configured by a long hole.

  According to a ninth aspect of the present invention, the operation control unit sets a time determined based on a time obtained by dividing a half cycle of the piston by the number of the pressing members as the predetermined time. A polyurethane foam production apparatus according to any one of the third to eighth aspects is provided.

  In general, carbon dioxide in a supercritical state is not liquid. In the present invention, liquefied carbon dioxide includes carbon dioxide in a supercritical state, a subcritical state, and a liquid state. Subcritical carbon dioxide is liquid carbon dioxide whose pressure is higher than the critical pressure of carbon dioxide and whose temperature is lower than the critical temperature, or whose pressure is lower than the critical pressure of carbon dioxide and whose temperature is critical. Carbon dioxide in a liquid state at a temperature or higher and a state in which both the temperature and pressure are less than the critical point but close to this, specifically, carbon dioxide having a temperature of 20 ° C. or higher and a pressure of 5 MPa or higher. .

  According to the present invention, a plurality of detected members are used as a configuration for generating a pump operation signal for opening the on-off valve in conjunction with a supply pump that supplies liquid A and liquid B to the discharge device. Therefore, the pump operation signal can be continuously generated in a short time. Therefore, for example, even when the pump operation is slow, the opening / closing control of the opening / closing valve can be controlled in a short cycle in conjunction with the pump operation signal generated at short intervals. Accordingly, an appropriate amount can be supplied without causing excessive supply due to a shift in the stop timing of the supply of liquefied carbon dioxide.

  According to the third aspect of the present invention, the pump operation signal can be continuously generated in a time shorter than one cycle of the piston by the plurality of detected members arranged along the reciprocating direction of the piston. it can. Therefore, the predetermined time for switching the on-off valve to be closed can be set to a time shorter than one cycle of the piston, and deviation of the stop timing of the supply of liquefied carbon dioxide can be reduced. Therefore, an appropriate amount of liquefied carbon dioxide can be supplied.

  In the above configuration, by providing the pressing member with the same dimension as the stroke width of the reciprocating motion of the piston, the pump operation signal can be generated at equal time intervals during the operation of the piston. By attaching the pressing member to the pressing member holding member having a long hole as an attachment region, the number of attachments and the attachment interval can be freely adjusted, and the generation interval and generation timing of the pump operation signal can be adjusted. .

  Hereinafter, a polyurethane foam manufacturing apparatus according to an embodiment of the present invention will be described with reference to the drawings.

(First embodiment)
Drawing 1A is a figure showing typically composition of a polyurethane foam manufacture device concerning a 1st embodiment of the present invention. The polyurethane foam manufacturing apparatus 1 according to the first embodiment shown in FIG. 1A shows an apparatus according to an embodiment in which liquefied carbon dioxide is supplied to the polyol component. The component liquid and the isocyanate component mixed with liquefied carbon dioxide 100 (see FIG. 2) stored in the liquefied carbon dioxide container 20 are transported while being heated using the warmer 3 and the hose heater 4 and sprayed. It is a device that mixes and discharges in the gun 5.

  As shown in FIG. 1A, the polyurethane foam manufacturing apparatus 1 stores a liquefied carbon dioxide container 20, a polyol component storage container 30 storing B liquid mainly containing polyol, and A liquid mainly containing polyisocyanate. A primary piping L11 and a secondary piping L12 that constitute an example of a feeding piping that conveys the liquefied carbon dioxide 100 (the upstream side from the check valve 29 as will be described later). L12a, the downstream side is L12b), a B liquid pipe L13 that is an example of a supply pipe that transports B liquid, and an A liquid pipe L14 that is an example of a supply pipe that transports A liquid are discharge devices. It has a configuration communicating with a certain spray gun 5.

  The starting end of the primary pipe L <b> 11 that conveys the liquefied carbon dioxide 100 is connected to the connector 22 of the liquefied carbon dioxide container 20. A first pressure gauge 25 for measuring the pressure of the filter 23, the blow valve 24, and the primary pipe L11 is provided in the middle of the primary pipe L11. The terminal end of the primary pipe L11 is connected to the secondary pipe L12 via an on-off valve 26 and a needle valve 27 which is an example of a throttle mechanism. The secondary pipe L12 is provided with a second pressure gauge 28 and a check valve 29 for measuring the pressure in the secondary pipe L12, and a mixer 32 provided in the B liquid pipe L13. It is connected to the.

  The B liquid pipe L <b> 13 includes a B liquid supply pump 31 and a mixer 32, and communicates with the spray gun 5. The A liquid pipe L <b> 14 includes the A liquid supply pump 41 and communicates with the spray gun 5. The spray gun 5 mixes the A liquid fed by the A liquid piping L14 and the B liquid piping L13 with the B liquid mixed with the liquefied carbon dioxide 100 by the mixer 32, and discharges it from the discharge port. The A liquid pipe L14 and the B liquid pipe L13 are provided with the heater 3 and the hose heater 4 as described above. Thereby, the reaction condition (resin reaction) can be stabilized by heating the liquid to be fed and keeping the temperature constant, and the reactivity at the time of discharge from the spray gun 5 can be increased. . That is, by heating the liquid flowing through the A liquid pipe L14 and the B liquid pipe L13 by the heater 3 and the hose heater 4, carbon dioxide is easily dispersed in the A liquid and / or the B liquid, and the polyurethane foam Foaming can be promoted. As shown in FIG. 1B, the warmer 3 is composed of two warmers 3a and 3b, and is configured to independently heat the liquid flowing in the liquid A pipe L14 and the liquid B pipe L13. May be. Similarly, the hose heater 4 is composed of two hose heaters 4a and 4b as shown in FIG. 1B, and is configured to independently heat the liquid flowing in the A liquid pipe L14 and the B liquid pipe L13. May be.

  In the example of FIG. 1A, the liquefied carbon dioxide 100 is configured to be mixed with the B liquid, but may be configured to be mixed with both the A liquid and the B liquid. In this case, a mixer 42 (see FIG. 1B) is provided in the A liquid pipe L14, the end side of the secondary pipe L12 is branched, and the branched ends are connected to the mixers 32 and 42, respectively. You can do it. Further, the liquefied oxygen dioxide 100 may be configured to be mixed with the A liquid instead of the B liquid. In this case, the mixer may be provided in the A liquid pipe, and the end of the secondary pipe L12 may be connected to the mixer provided in the A liquid pipe.

  As shown in FIG. 2, the liquefied carbon dioxide container 20 is a container with a siphon tube in which a siphon tube L20 is provided. In addition, a container is not specifically limited, The thing provided generally may be used. For example, a container such as a small gas cylinder that has high pressure resistance and is not thermally insulated may be used as the liquefied carbon dioxide container 20.

  The liquefied carbon dioxide container 20 is provided with a heating member 21 for heating the container. The heating member 21 is for heating the liquefied carbon dioxide 100 stored in the liquefied carbon dioxide container 20 to increase the pressure inside the container. Specific examples of the heating member 21 include an electric heater, a steam heater, and a hot water tank in which a container can be immersed.

  The heating member 21 heats the liquefied carbon dioxide 100 so that the internal pressure of the liquefied carbon dioxide container 20 is about 5 to 8 MPa, preferably 7 to 8 MPa. Hereinafter, the internal pressure set to the said range by heating the liquefied carbon dioxide container 20 is described as a 1st pressure. In addition, although the gas cylinder marketed normally changes with temperature conditions, since an internal pressure is about 3-7 Mpa and does not satisfy the said 1st pressure in winter, it may heat by the heating member 21, In the summer, the first pressure may be reached without being heated. In this case, heating by the heating member 21 is not performed. Note that the heating temperature by the heating member 21 is set to 40 ° C. or lower. The heating member 21 is provided for the purpose of setting the inside of the liquefied carbon dioxide container 20 to the first pressure. For this reason, for example, when the outside air temperature at midsummer is extremely high and the pressure in the container exceeds the range of the first pressure, cooling to cool the liquefied carbon dioxide container 20 so as to adjust to the range of the first pressure. A member may be used instead of the heating member 21.

  The reason why the first pressure is set to the above value is to prevent the liquefied carbon dioxide 100 in the liquefied carbon dioxide container 20 and the primary pipe L11 from being vaporized. For this reason, if the temperature condition is such that the liquefied carbon dioxide 100 does not vaporize, the first pressure can be set near the critical pressure (7.382 MPa (abs)) or higher than the critical pressure.

  The primary pipe L11 is made of, for example, a 6φ stainless steel pipe, and feeds the liquefied carbon dioxide 100 supplied from the liquefied carbon dioxide container 20 while maintaining the first pressure. The filter 23 provided in the primary pipe L11 is for removing foreign matter in the primary pipe L11, and foreign matter is added to the needle valve 27 and the like for narrowing the feeding flow path of the liquefied carbon dioxide 100. Prevent clogging. The first pressure gauge 25 is provided so as to detect the pressure in the primary pipe L11, that is, the internal pressure of the liquefied carbon dioxide container 20. Based on the detection value of the first pressure gauge 25, the heating operation of the heating member 21 is controlled.

  The on-off valve 26 is a member that connects the primary pipe L11 and the secondary pipe L12, and is electrically controlled to open and close by a control unit 10 as an example of a valve control unit described later. The on-off valve 26 has a pressure adjusting function of a primary pressure system on the upstream side and a secondary pressure system on the downstream side thereof. That is, the pressure in the primary pipe L11 and the secondary pipe L12 connected to both ends of the on-off valve 26 is different.

  The needle valve 27 provided in the secondary pipe L12 adjusts the flow amount of the liquefied carbon dioxide 100 sent from the primary pipe L11 to the secondary pipe L12 by adjusting the amount of restriction. The needle valve 27 is configured such that the user can manually adjust the flow rate of the liquefied carbon dioxide 100 that feeds the secondary pipe L12 according to the use environment of the device such as the outside air temperature and the degree of foaming of the polyurethane foam. Has been.

  The check valve 29 provided in the secondary pipe L12 is configured to flow the liquefied carbon dioxide 100 so that the B liquid in the B liquid pipe L13 communicating with the mixer 31 does not flow into the secondary pipe L12. It regulates the direction.

  The secondary pipe L12b has a small diameter smaller than that of the primary pipe L11. In the first embodiment, the secondary pipe L12b is composed of a 3φ stainless steel pipe. Since the flow rate of the liquefied carbon dioxide 100 is different between the upstream side and the downstream side of the needle valve 27, the secondary pipe L12b can have a small diameter to reduce the pressure drop. Since the flow rate of the liquefied carbon dioxide 100 to be fed is reduced, the secondary pipe L12 is in a second pressure state that is lower than the first pressure in the primary pipe L11. The specific value of the second pressure is 4 to 7 MPa, preferably 5 to 6 MPa, and is preferably substantially the same as or slightly higher than the discharge pressure (when stopped) of the spray gun 5.

  The B liquid pipe L <b> 13 and the A liquid pipe L <b> 14 feed the B liquid and the A liquid to the spray gun 5 at a pressure pressurized by the supply pumps 31 and 41, respectively.

  Examples of the polyisocyanate that is the main component of the liquid A include aromatic polyisocyanate, aliphatic diisocyanate, alicyclic diisocyanate, and a part of the isocyanate group of aromatic polyisocyanate, aliphatic diisocyanate, or alicyclic diisocyanate. What modified | denatured to urethane and / or urea may be used, and what modified a part of isocyanate group into burette, allophanate, carbodiimide, oxaziridone, acid, imide, etc. may be used.

  Examples of the polyol which is the main component of the liquid B include ethylene glycol, propanediol, butanediol, diethylene glycol, dipropylene glycol, tetramethylene glycol, hexamethylene glycol, cyclohexanedimethanol, bisphenol A, 3-methyl-1, 5 -At least 1 sort (s) is mentioned among compounds which have active hydrogen, such as pentanediol, glycerin, trimethylol propane, pentaerythritol, sucrose, glucose, fructose sorbitol, methylglycoxide. Further, for example, the other active hydrogen-containing compound includes at least one of amines such as ethylenediamine, propylenediamine, diethylenetriamine, toluenediamine, metaphenylenediamine, diphenylmethanediamine, xylylenediamine, and the like. .

  Furthermore, a polyether polyol may be used as the active hydrogen group-containing compound. As the polyether polyol, for example, a monomer such as alkylene oxide is known by using at least one of the above-exemplified active hydrogen compounds as an initiator. What is obtained by addition polymerization by a method is mentioned. Examples of the monomer used for the addition polymerization reaction include ethylene oxide, propylene oxide, glycidyl ether, methyl glycidyl ether, t-butyl glycidyl ether, and phenyl glycidyl ether.

  Further, a polyester polyol may be used as the active hydrogen group-containing compound. Examples of the polyester polyol include ethylene glycol, propanediol, butanediol, diethylene glycol, dipropylene glycol, trimethylene glycol, tetramethylene glycol, and hexamethylene glycol. , Decamethylene glycol, neopentyl glycol, 3-methyl-1,5-pentanediol, glycerin, trimethylolpropane, pentaerythritol, sorbitol, at least two compounds having a hydroxyl group such as bisphenol A 1 type, for example, adipic acid, malonic acid, succinic acid, tartaric acid, pimelic acid, sebacic acid, oxalic acid, phthalic acid, terephthalic acid, azelaic acid, Use at least one of compounds having at least two carboxyl groups such as merit acid, glutaconic acid, α-hydromuconic acid, β-diethylsuccinic acid, hemimellitic acid, 1,4-cyclohexanedicarboxylic acid, etc. And those produced by known methods.

  Furthermore, in addition to the above polyester polyol, a polyester polyol produced by transesterification of a polyalkylene terephthalate polymer and a low molecular diol can also be used. Examples of the low molecular weight diol include ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, butanediol, glycerol, trimethylolpropane, and cyclohexanedimethanol.

  The catalyst for proceeding the urethanation reaction between the polyisocyanate and the active hydrogen group-containing compound is not particularly limited, and for example, a known catalyst can be used. Further, the foam stabilizer is not particularly limited, and for example, all those used in the production of polyurethane foam can be used. Further, additives such as a catalyst, a foam stabilizer, a flame retardant and the like are usually mixed on the B liquid side. The polyurethane foam of the present invention includes polyisocyanurate foam.

  The pressure in the B liquid pipe L13 and the A liquid pipe L14, that is, the discharge pressure of the spray gun 5 is controlled by the supply pumps 31 and 41 to be a constant pressure (4 to 6 MPa). As the supply pumps 31 and 41, for example, a double-acting proportioning pump that can send liquid to the spray gun 5 at both the up and down strokes of the pump with one piston and one cylinder can be used. The pressure in the B liquid pipe L13 and the A liquid pipe L14 is driven by the supply pumps 31 and 41, because the B liquid and the A liquid pulsate in the B liquid pipe L13 and the A liquid pipe L14. Although it fluctuates, when the supply pumps 31 and 41 are stopped, they are configured to be equal to or higher than a predetermined threshold pressure (for example, about 5 MPa). That is, as shown in FIG. 3A, the supply pumps 31 and 41 are configured so that the piston is moved by a pressure adjusting mechanism 50 such as an air cylinder or a hydraulic cylinder so that the liquid B and the liquid A are always supplied at a constant pressure. It is configured. For example, when the spray gun 5 is operated and the liquid in the B liquid pipe L13 and the A liquid pipe L14 is consumed, the discharge pressure in the B liquid pipe L13 and the A liquid pipe L14 decreases. The supply pumps 31 and 41 are driven to adjust the discharge pressure to be equal to or higher than the threshold pressure (for example, about 5.5 MPa).

  As described above, the internal pressure in the secondary pipe L12 is adjusted by supplying the liquefied carbon dioxide 100 by the on-off valve 26 and adjusting the degree of opening of the needle valve 27 (throttle amount). As a result of the decrease in the flow rate of the liquefied carbon dioxide 100, the pressure is reduced to the second pressure. Therefore, the secondary pressure system in the secondary pipe L12, the B liquid pipe L13, and the A liquid pipe L14 adjusts the pressures of the A liquid and the B liquid by driving the supply pumps 31 and 41, and opens and closes. Liquefied carbon dioxide 100 supplied from the primary pressure system in the primary pipe L11 due to the pressure difference between the primary pressure system and the secondary pressure system by switching between opening and closing by the valve 26 and adjusting the throttle amount of the needle valve 27. The flow rate is adjusted. As a result of adjusting the flow rate of the liquefied carbon dioxide 100, the pressure of the secondary pressure system becomes substantially uniform.

  In the polyurethane foam manufacturing apparatus according to the first embodiment, the adjustment (measurement) of the flow rate of the liquefied carbon dioxide 100 is automated by switching the opening / closing valve 26 in conjunction with the operation of the supply pumps 31, 41. It is configured. More specifically, switching between opening and closing of the on-off valve 26 in conjunction with the operation of the supply pumps 31 and 41 is performed based on an output signal from a switch 51 that is an example of a detection member. Thereby, there is no need to provide a separate pump for adjusting (measuring) the flow rate of the liquefied carbon dioxide 100.

  FIG. 3B shows an enlarged configuration diagram of the switch portion shown in FIG. 3A. As shown in FIGS. 3A and 3B, the switch configuration for switching between opening and closing of the on-off valve 26 includes a plurality of pressing members 53 attached to the frame 35 via the pressing member holding member 52, and the pressing member 53. This is performed by the switch 51 pressed by. The frame 35 is connected to the supply pumps 31 and 41 and is driven in the same manner as both the supply pumps 31 and 41. When the frame 35 is driven, the pressing member holding member 52 and the pressing member 53 reciprocate as indicated by an arrow 90.

  As shown in FIG. 3C, the pressing member holding member 52 is a member in which a long hole 55 extending along the operation direction of the supply pumps 31 and 41 is provided in a member on a flat plate. The elongated hole 55 as an example of the attachment region of the pressing member holding member has a longitudinal dimension L, and the dimension L is substantially equal to the stroke width of the supply pumps 31 and 41 in this embodiment. . As shown in FIG. 3D, a screw having a semicircular head is fixed to the elongated hole 55 with a nut 53 a, and the head portion of the screw functions as the pressing member 53. Thus, by attaching the pressing member 53 with the long hole 55 and the screw, the positioning of the pressing member 53 and the setting change of the number can be facilitated.

  The number of the pressing members 53 attached to the long hole 55 may be plural, and is not particularly limited. In the present embodiment, five pressing members 53 are provided. It is preferable that the pressing members are provided at substantially equal intervals in the vicinity of both ends and the middle portion of the 53 long hole 55.

  The switch 51 is composed of, for example, a micro switch or a limit switch. The switch 51 is provided with an operating portion 54 provided so as to physically contact the pressing member holding member 52 and the pressing member 53. The operating portion 54 is provided with a freely rotatable roller at the tip, and flexibly follows the movement of the pressing member holding member 52 and the pressing member 53 having irregularities.

  When the pressing member holding member 52 and the pressing member 53 reciprocate, the operating portion 54 is pressed by the protrusion of the pressing member 53, and the switch 51 detects the state. The switch 51 outputs a pump operation signal to the control unit 10 when detecting that the operating unit 54 is pressed.

  The configuration for detecting that the supply pumps 31 and 41 are moving is not the configuration for detecting physical contact between the two members as described above, but, for example, a method such as optical or magnetic force detection. It may be.

  FIG. 4 is an enlarged configuration diagram of a modified example of the switch portion. In the example shown in FIG. 4, a plurality of reflection plates 57 are provided on the surface of a plate-like holding member 52 b attached to the frame so as to be arranged at equal intervals along the operation direction of the supply pumps 31 and 41. The pump operation signal may be transmitted when the light S emitted from the light detection unit 51b is reflected by the surface of the reflection plate 57 and enters the light detection unit 51b. Further, instead of the reflection plate 57, a through hole may be provided in the holding member 52b, and light transmission through the through hole may be detected.

  Further, for example, a magnet, for example, a plurality of rod-shaped magnets arranged so that the same poles are opposed to each other is provided in the supply pumps 31 and 41, and the magnetic force detection is arranged so as to face the magnetic force and detects the direction of the magnetic field. The operation of the supply pumps 31 and 41 may be detected by a sensor.

  In each of the above embodiments, a member to be detected such as a pressing member is fixed to the frame as a member that works together with the supply pump, and the detection member that detects the operation of the member to be detected is fixed to the movable part of the supply pump. However, the detection member may be attached to the frame and the detection target member may be fixed to the movable part of the supply pump.

  FIG. 5 is a block diagram of a control unit of the polyurethane foam manufacturing apparatus. The control unit 10 transmits an operation control unit 11, a switch signal receiving unit 12 that detects a pump operation signal transmitted from the switch 51, a timer unit 13 that counts a predetermined time, and a trigger signal that opens and closes the on-off valve 26. And a trigger signal transmission unit 14 for performing the operation.

  When the switch signal receiving unit 12 receives the switch signal of the switch 51, the operation control unit 11 transmits a trigger signal for causing the trigger signal transmitting unit 14 to open the on-off valve 26, and at the same time a predetermined time T of the timer unit 13. Start counting. When the count of the predetermined time T of the timer unit 13 is completed, the operation control unit 11 causes the trigger signal transmission unit 14 to transmit a trigger signal that causes the on-off valve 26 to be closed. As a result, as shown in the graph of FIG. 6A, the opening / closing valve 16 is opened until the predetermined time T elapses after the switch signal receiving unit 12 detects the pump operation signal, and the secondary pressure from the primary pressure system. Liquefied carbon dioxide 100 is supplied to the pressure system.

  When the supply pumps 31 and 41 are continuously driven, the switch signal receiving unit 12 outputs a new pump operation signal before the timer unit 13 finishes counting the predetermined time T as shown in the graph of FIG. 6B. When detected, the operation control unit 11 resets the count of the predetermined time T of the timer unit 13 and performs control so as to start counting of the predetermined time T of the timer unit 13 again. While the supply pumps 31 and 41 are being driven, the pressure of the secondary pressure system is lower than the threshold pressure. Therefore, the control uses the pressure of the secondary pressure system higher than the primary pressure system, The pressure of the primary pressure system can be recovered to the threshold pressure or higher at an early stage.

  If the reception of the next pump operation signal is not confirmed during the predetermined time T of the timer unit 13 that is started by receiving the pump operation signal, the trigger signal transmission unit 14 sets the on-off valve 26 in the closed state. Trigger signal to be sent. That is, since the pump operation signal is continuously transmitted when the supply pump is operating, the open / close valve 26 is maintained open, and the supply pump is stopped and then opened and closed after a predetermined time T has elapsed. The valve 26 switches to the closed state.

  As described above, when the trigger signal for switching between opening and closing of the on-off valve 26 is controlled to be transmitted, the supply pumps 31 and 41 that operate continuously for a predetermined time T counted after receiving the pump operation signal. It is necessary to set it slightly longer than the transmission interval t between two continuous pump operation signals transmitted by the reciprocating operation of the piston. That is, when the predetermined time is shorter than the transmission interval, the predetermined time T elapses before the second and subsequent pump operation signals are transmitted, and the on-off valve 26 is switched to the closed state. In addition, when the predetermined time T is significantly longer than the transmission interval t, the supply pumps 31 and 41 are stopped and only the liquefied carbon dioxide, which is a foaming agent, is supplied even though the liquid A and the liquid B are not supplied. Will be supplied. Therefore, the foaming agent is likely to be excessive.

  Here, since the polyurethane foam manufacturing apparatus according to the present embodiment is provided with a plurality of pressing members that are members to be detected, a plurality of pump operation signals are transmitted during one stroke of the reciprocating piston and are continuously transmitted. The transmission interval t between the two pump operation signals can be shortened. Therefore, the predetermined time T can be shortened, the time required for the on-off valve 26 to be closed after the supply pumps 31 and 41 are stopped can be shortened, and the supply of excessive foaming agent can be suppressed. it can.

  The principle by which the predetermined time can be shortened will be described with reference to FIGS. 7A and 7B. FIG. 7A is a timing chart when there is only one member to be detected and a pump operation signal is transmitted by making physical contact with the switch at the lowest point of the reciprocating motion of the piston. In this case, a pump operation signal is transmitted every cycle (about 2 seconds) which is the reciprocating motion of the piston. Therefore, the predetermined time T needs to be a little over 2 seconds. Therefore, although the pump is stopped and the supply of the liquid A and the liquid B is stopped, the open / close valve 26 is maintained open for about 2 seconds and liquefied carbon dioxide is supplied.

  On the other hand, by providing a plurality (five) of members to be detected as shown in FIG. 7B, 10 pump operation signals are transmitted during one stroke of the piston. Therefore, the predetermined time T can be set to a time slightly longer than 0.2 seconds obtained by dividing the half cycle (about 1 second) that is the forward or backward movement of the piston by the number of the detected members, and the piston stops. After that, the on-off valve 26 can be closed in about 0.2 seconds. Therefore, after the supply of the liquid A and the liquid B is stopped, the supply of the liquefied carbon dioxide can be stopped in a short time.

  In addition, due to the pulsation of the supply pumps 31 and 41, the pressure in the B liquid pipe L13 and the A liquid pipe L14, that is, the discharge pressure of the spray gun 5 is temporarily higher than the second pressure in the secondary pipe L12. Although it may become high, the backflow of the B liquid and / or A liquid in the secondary piping L12 in that case is prevented by the check valve 29.

  Next, the operation of the polyurethane foam manufacturing apparatus according to the first embodiment will be described. First, the preparation procedure performed before manufacturing a polyurethane foam using the polyurethane foam manufacturing apparatus concerning this 1st Embodiment is demonstrated.

  In the first embodiment, first, the liquefied carbon dioxide container 20, the polyol component storage container 30, and the polyisocyanate component storage container 40 that are raw materials are connected using various pipes L <b> 11 to L <b> 14, and then the pipes L <b> 13 and L <b> 14. Are filled with liquid B and liquid A, respectively.

  Next, the liquefied carbon dioxide 100 is filled into the primary pipe L11. In this operation, the liquefied carbon dioxide 100 is fed into the primary pipe L11 with the on-off valve 26 closed. However, since air or the like is present in the primary pipe L11, one end must be opened. In this case, the liquefied carbon dioxide 100 cannot be filled. Therefore, in the polyurethane foam manufacturing apparatus 1 according to the first embodiment, the primary pipe L11 is provided with the blow valve 24 and the primary pipe L11 is filled with the liquefied carbon dioxide 100. For this reason, the position where the blow valve 24 is provided is preferably in the vicinity of the upstream side of the on-off valve 26 of the primary pipe L11. By providing the blow valve 24 in this manner, the trouble at the time of starting up the apparatus can be facilitated, and the liquefied carbon dioxide 100 remaining in the pipe can be discharged when the apparatus is stopped, and the pressure can be released. .

  After the filling, the liquefied carbon dioxide container 20 is heated by the heating member 21 to adjust the pressure in the primary pipe L11 to the first pressure (7 to 8 MPa). The temperature control of the heating member 21 may be configured to be controlled by a computer so as to maintain the first pressure based on the output value of the first pressure gauge 25, for example.

  Thereafter, the on-off valve 26 and the needle valve 27 are opened, the liquefied carbon dioxide 100 is filled in the secondary pipe L12, and the throttle amount (opening degree) of the needle valve 27 is adjusted. The pressure in the secondary pipe L12 naturally decreases due to a decrease in the flow rate of the liquefied carbon dioxide 100, and is almost balanced with the pressure (4 to 6 MPa) in the B liquid pipe L13 and the A liquid pipe L14. The throttle amount of the needle valve 27 may be adjusted according to the outside air temperature when the polyurethane foam manufacturing apparatus 1 is used, for example. The throttle amount of the needle valve 27 is preferably adjusted so that, for example, the flow rate of the liquefied carbon dioxide 100 is increased when the outside air temperature is low, and the flow rate is decreased when the outside temperature is high.

  When the pressure in the secondary pipe L12 becomes the second pressure, the on-off valve 26 is closed. Thereby, the preparatory process for manufacturing a polyurethane foam is completed.

  In addition, adjusting the 1st pressure to 7-8 Mpa as mentioned above is based on the phase state of a carbon dioxide. That is, carbon dioxide has a relationship as shown in the state diagram of FIG. 8, and has a critical point (7.382 MPa (abs), 31.1 ° C.). Therefore, as long as the pressure near the critical point is maintained, carbon dioxide does not become a gas. Therefore, by setting the first pressure to 7 to 8 MPa, the liquid state can be maintained if the temperature in the primary pipe L11 is about room temperature (for example, 20 ° C.).

  In general, it is said that the discharge pressure of the spray gun 5 is 4 to 7 MPa, preferably about 5 to 6 MPa. If the second pressure is set lower than this, the liquefied carbon dioxide 100 is added to the B liquid pipe L13. Can not supply. For this reason, the second pressure is set to a pressure that is substantially the same as or slightly larger than the discharge pressure. In addition, even after the adjustment (measurement) of the flow rate that passes through the needle valve 27 and is supplied to the liquid A and / or the liquid B is completed, even if the liquefied carbon dioxide 100 is vaporized, it is particularly large in the production of polyurethane foam. There is no problem.

  When the preparation step is completed, polyurethane foam is manufactured by the polyurethane foam manufacturing apparatus 1. Hereafter, the manufacturing process of a polyurethane foam is demonstrated. FIG. 9 is a flowchart showing the operation of the control unit 10.

  First, the spray gun 5 shown in FIG. 1A is operated, and the liquid A, liquid B, and liquefied carbon dioxide 100 supplied into the spray gun 5 in the preparation step are mixed while being heated by the heater 3 and the hose heater 4. Then, the liquid mixture is discharged from the spray gun 5. At this time, the liquid mixture discharged from the spray gun 5 vaporizes the liquefied carbon dioxide 100 and reacts and solidifies to form polyurethane foam. At this time, the discharge from the spray gun 5 consumes the A and B liquids in the A liquid pipe L14 and the B liquid pipe L13, and the liquefied carbon dioxide 100 in the secondary pipe L12. The pressure (pressure of the secondary pressure system), that is, the discharge pressure decreases.

  When the discharge pressure becomes lower than a predetermined threshold pressure (for example, about 5 MPa), the supply pumps 31 and 41 are driven to supply the A liquid and the B liquid into the A liquid pipe L14 and the B liquid pipe L13, respectively. . At this time, when the pressing member 53 that moves the piston contacts the switch 51 as shown in FIG. 3A by the driving, the switch 51 transmits a pump operation signal to the control unit 10.

  When the switch signal receiving unit 12 (see FIG. 4) detects the pump operation signal (step S1), the operation control unit 11 transmits a trigger signal that causes the trigger signal transmitting unit 14 to open the on-off valve 26 (see FIG. 4). Along with step S2), the timer section 13 starts counting for a predetermined time T (step S3).

  When the on-off valve 26 is opened by step S2, the liquefied carbon dioxide 100 is sent into the secondary pipe L12. At this time, the flow rate of the liquefied carbon dioxide 100 decreases according to the throttle amount of the needle valve 27, and the pressure is adjusted so that the inside of the secondary pipe L12 becomes the second pressure (for example, 5 to 6 MPa).

  After step S3, the operation control unit 11 determines whether or not the timer 13 has completed counting the predetermined time T (step S4). In step S4, when the counting is completed, the operation control unit 11 causes the trigger signal transmission unit 14 to transmit a trigger signal for closing the on-off valve 26 (step S7). In step S4, when the counting is not completed, that is, the operation control unit 11 determines whether or not the pump operation signal is further detected from the switch signal receiving unit 12 (step S5).

  In step S5, when the switch signal receiving unit 12 does not detect a new switch signal, the operation control unit 11 returns to step S4. In step S5, when the switch signal receiving unit 12 detects a new switch signal (YES in step S5), the operation control unit 11 resets the count of the predetermined time T of the timer unit 13 (step S6). The process proceeds to step S3, and the timer unit 13 starts counting the predetermined time T from the beginning.

  When the pressure of the secondary pressure system becomes equal to or higher than a predetermined threshold pressure by driving the supply pumps 31 and 41 and opening the on-off valve 26, the drive of the supply pumps 31 and 41 is stopped. In this case, since the switch 51 does not transmit a switch signal, the timer unit 13 can complete counting after a predetermined time T has elapsed.

  In step S4, when the counting is completed, the operation control unit 11 causes the trigger signal transmission unit 14 to transmit a trigger signal for closing the on-off valve 26 (step S7).

  With the above operation, the pressure of the secondary pressure system is restored to the second pressure. The operations in steps S1 to S7 may be performed while discharging the mixed liquid by the spray gun 5, or the operation of the spray gun 5 is continued until the reduced secondary pressure system pressure returns to the second pressure. You may make it not accept.

  As described above, according to the polyurethane foam manufacturing apparatus 1 according to the first embodiment, the open / close valve 26 is switched according to the supply operation of the liquid A and the liquid B, whereby the liquefied carbon dioxide container The liquefied carbon dioxide 100 is fed to the secondary pressure system using the pressure difference between the inside 20 and the discharge pressure (pressure difference between the primary pressure system and the secondary pressure system) as the conveying force. Thereby, feeding of the liquefied carbon dioxide 100 can be performed without using a pump, and vaporization of carbon dioxide accompanying use of the pump can be prevented.

  Further, the flow rate of the liquefied carbon dioxide 100 to the secondary pipe L12 is adjusted with high accuracy so that the inside of the secondary pipe L12 is lower than the first pressure by the opening / closing valve 26 and the needle valve 27, The liquefied carbon dioxide 100 can be prevented from being fed into the spray gun 5 without limitation by the high first pressure.

  Moreover, according to the polyurethane foam manufacturing apparatus 1 according to the first embodiment, after detecting the start of driving of the supply pumps 31 and 41, the on-off valve 26 is opened until a predetermined time T elapses, and within the predetermined time T When the drive of the supply pumps 31 and 41 is newly detected, the count for the predetermined time T is reset and the count is started again. Thereby, even if the drive time of the supply pumps 31 and 41 (time for moving the piston) is irregular, the on-off valve can be opened for an appropriate time according to the drive time. Therefore, it is possible to stabilize the discharge pressure by adjusting the flow rate of the liquefied carbon dioxide 100 with high accuracy, and it is possible to eliminate the need to strictly measure carbon dioxide using a pump. In addition, after the operation of the supply pump is stopped, the on-off valve 26 can be switched to a closed state in a short time, and excessive supply of liquefied carbon dioxide can be suppressed.

  Moreover, according to the polyurethane foam manufacturing apparatus 1 concerning this 1st Embodiment, it comprises so that the drive of the supply pumps 31 and 41 may be detected when the supply pumps 31 and 41 and the switch 51 contact physically. Therefore, the configuration is simple and inexpensive. In addition, the structure which detects the drive of supply pumps 31 and 41 is not limited to this, For example, you may comprise so that it may detect with said structure demonstrated in FIG.

  Further, according to the polyurethane foam manufacturing apparatus 1 according to the first embodiment, the first pressure is set to 5 MPa to 8 MPa, and the second pressure and the discharge pressure are set to 4 MPa to 7 MPa, respectively. The liquid state can be maintained. Thereby, since carbon dioxide can be fed to the spray gun 5 in a liquid state (including a supercritical state and a subcritical state), cooling for preventing vaporization of the liquefied carbon dioxide 100 as in the conventional example. There is no need to provide an apparatus, and the apparatus can be reduced in size and cost. For example, when the outside air temperature is high and the pressure in the liquefied carbon dioxide container 20 is the first pressure as in the summer, the liquefied carbon dioxide container 20 can be used as it is, while in the winter. When the outside air temperature is low and the pressure of the liquefied carbon dioxide container 20 is less than the first pressure, the inside of the container can be pressurized to the first pressure using a pressurizing means such as the warmer 3.

(Second Embodiment)
FIG. 1B is a diagram schematically showing a configuration of a polyurethane foam manufacturing apparatus 1A according to the second embodiment of the present invention. The polyurethane foam manufacturing apparatus 1A according to the second embodiment shown in FIG. 1B includes a discharge device 2 and a control unit 10A instead of the spray gun 5 and the control unit 10, and further includes an outside air temperature detection unit 60. It differs from the polyurethane foam manufacturing apparatus 1 concerning one Embodiment. Hereinafter, the differences will be mainly described in detail.

  The polyurethane foam manufacturing apparatus 1A according to the second embodiment includes the warmers 3a and 3b and the hose heaters 4a and 4b instead of the warmer 3 and the hose heater 4, and is mixed with the A liquid pipe L14. Although it differs from the polyurethane foam manufacturing apparatus 1 according to the first embodiment in that the machine 42 is further provided, since these have been described above, redundant description will be omitted.

  The discharge device 2 includes an operation unit 6 in a spray gun 5. The operation unit 6 is disposed in a part of the spray gun 5 so that a user who is using the apparatus can easily operate the operation unit 6. The operation unit 6 is provided with an adjustment button or an adjustment knob (not shown) to which adjustment information on the foaming degree of the polyurethane foam discharged from the spray gun 5 is input. The user can obtain a polyurethane foam having a desired foaming degree by operating the adjustment button or the adjustment knob and inputting desired foaming degree information to the operation unit 6.

  In the second embodiment, the degree of foaming of the polyurethane foam is adjusted by adjusting the throttle amount of the needle valve 27. Here, it is assumed that the aperture value can be adjusted by, for example, switching in 10 steps of 1 to 10. As described above, since the liquefied carbon dioxide 100 is easily affected by the outside air temperature (ambient temperature), an appropriate throttle amount of the needle valve 27 varies depending on the outside temperature. For this reason, in the second embodiment, an outside air temperature detection unit 60 is provided. As described above, after the adjustment (measurement) of the flow rate supplied to the liquid A and / or the liquid B is completed, the outside air temperature detection unit 60 is installed on the polyurethane foam even if the liquefied carbon dioxide 100 is vaporized. It is preferable to be provided in the vicinity of the needle valve 27 because there is no particular problem in manufacturing.

  The control unit 10A is configured to control the throttle amount of the needle valve 27 based on the foaming degree adjustment information input to the operation unit 6 and the outside air temperature information detected by the outside air temperature detecting unit 60. Specifically, as shown in FIG. 10, in addition to the control unit 10, the control unit 10 </ b> A further transmits a foam amount adjustment information receiving unit 15 that receives expansion degree adjustment information, and a throttle amount control signal to the needle valve 27. And a diaphragm amount control signal transmitter 17 for performing the operation.

  The foaming degree adjustment information includes, for example, information for adjusting the reference aperture amount in five stages of -2, -1, 0, +1, and +2. The operation control unit 11 stores a data table as shown in Table 1 below, for example. The data table is data that stores information on the reference throttle amount of the needle valve 27 that is a reference for the outside air temperature in association with each other.

  The control unit 10A determines the optimum throttle amount of the needle valve 27 after adjustment according to the foaming degree adjustment information received by the foaming degree adjustment information receiving unit 15 and the outside air temperature information detected by the outside air temperature detecting unit 60. . For example, when the foaming degree adjustment information is +1 and the outside air temperature information is 10 ° C., the throttle degree is optimally 6 (= 5 + 1).

  The valve control means 10A causes the throttle amount control signal transmitter 17 to transmit a throttle amount control signal for setting the needle valve 27 to the throttle amount (6 in the above example). Thereby, it is possible to automatically switch to the throttle degree of the needle valve 27 in consideration of the outside air temperature and the user's request. In addition, when the outside air temperature changes after the switching, it is preferable to automatically switch to the throttle degree of the needle valve 27 according to the outside air temperature information and the foaming degree adjustment information.

  According to the polyurethane foam manufacturing apparatus 1A according to the second embodiment of the present invention, the opening / closing valve 26 and the throttle degree of the needle valve 27 are controlled by the valve opening / closing means 10A. The adjustment can be performed with higher accuracy, and the need to strictly measure carbon dioxide using a pump can be eliminated.

  Further, according to the polyurethane foam manufacturing apparatus 1A according to the second embodiment of the present invention, the above configuration allows the user to spray without worrying about the difference in the degree of foaming caused by the outside air temperature around the on-off valve 26. By inputting desired foaming degree adjustment information to the operation unit 6 provided in the gun 5, it is possible to automatically switch to the optimum throttle amount of the needle valve 27.

  Moreover, according to the polyurethane foam manufacturing apparatus 1A according to the second embodiment of the present invention, the operation unit 6 for switching the throttle amount of the needle valve 27 is arranged in the spray gun 5, so that the user can switch the throttle amount. There is no need to move close to the needle valve 27. In general, since the liquefied carbon dioxide container 20, the polyol component storage container 30, and the polyisocyanate component storage container 40 are not easy to carry, the length of the A liquid pipe L14 and the B liquid pipe L13 is increased (for example, 100 m). Then, the user carries only the spray gun 5 and uses the apparatus 1A. For this reason, it is possible to drastically reduce the burden on the user by configuring the throttle amount of the needle valve 27 to be automatically controlled as described above.

  In addition, this invention is not limited to the said embodiment, It can implement in another various aspect. For example, in the second embodiment, the throttle degree of the needle valve 27 is automatically adjusted according to the foaming degree adjustment information and the outside air temperature information, but the present invention is not limited to this. For example, the throttle degree of the needle valve 27 may be adjusted according to any one of the foaming degree adjustment information and the outside air temperature information. Even in this case, the flow rate of the liquefied carbon dioxide 100 can be adjusted with higher accuracy than in the past, and the necessity of strictly measuring carbon dioxide using a pump can be eliminated.

In the above description, the needle valve 27 is provided as an example of the throttle mechanism, but the present invention is not limited to this. For example, the on-off valve 26 may be configured to have a throttle mechanism function.
In the above description, the on / off valve 26 is switched between open and closed in conjunction with the driving of the supply pumps 31 and 41. However, the present invention is not limited to this. For example, the opening / closing valve 26 may be switched between open and closed in conjunction with a pressure change in the supply pipes L13 and L14 that triggers the supply pumps 31 and 41 to be driven.

  Since the polyurethane foam production apparatus according to the present invention can solve the problem of vaporization of carbon dioxide due to the use of a pump, liquid (supercritical, subcritical or liquid) carbon dioxide is used as a foaming agent. It is useful as a production apparatus suitable for foaming polyurethane foam to be used.

It is a figure which shows typically the structure of the polyurethane foam manufacturing apparatus concerning 1st Embodiment of this invention. It is a figure which shows typically the structure of the polyurethane foam manufacturing apparatus concerning 2nd Embodiment of this invention. It is a figure which shows the structure of a liquefied carbon dioxide container. It is a partial enlarged view which shows the structure of a supply pump. It is an expanded block diagram of the switch part shown to FIG. 3A. It is a figure which shows the structure of the press member holding member used for the switch part shown to FIG. 3A. It is a figure which shows the attachment structure of the press member holding member and press member of FIG. 3C. It is an enlarged block diagram of the modification of a switch part. It is a block diagram of the control part of the polyurethane foam manufacturing apparatus concerning 1st Embodiment of this invention. It is a timing chart which shows the relationship between the ON / OFF state of a switch, and the open / close state of an open valve. It is a timing chart which shows the relationship between the ON / OFF state of a switch when the drive of a supply pump is continued, and the open / close state of an open valve. It is a timing chart of transmission of a pump operation signal when one member to be detected is provided. It is a timing chart of the transmission of the pump operation signal when five members to be detected are provided. It is a phase diagram of carbon dioxide. It is a flowchart which shows the manufacturing process of the polyurethane foam using the polyurethane foam manufacturing apparatus of FIG. It is a block diagram of the control part of the polyurethane foam manufacturing apparatus concerning 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Polyurethane foam manufacturing apparatus 2 Discharge apparatus 3 Heating machine 4 Hose heater 5 Spray gun 6 Operation part 10 Control part 11 Operation control part 12 Switch signal receiving part 13 Trigger signal transmission part 20 Liquefied carbon dioxide container 21 Heating member 22 Connector 23 Filter 24 Blow valve 25 First pressure gauge 26 On-off valve 27 Needle valve 28 Second pressure gauge 29 Check valve 30 Polyol component storage container 31 B liquid pump 32, 42 Mixer 35 Frame 40 Polyisocyanate component storage container 41 For A liquid Pump 50 Pressure adjusting mechanism 51 Switch 52 Pressing member holding member 53 Pressing member (detected member)
53a Nut 54 Actuator 55 Long hole 60 Outside air temperature detector L11 Primary piping L12, L12a, L12b Secondary piping L13 B liquid piping L14 A liquid piping

Claims (9)

A polyurethane foam manufacturing apparatus that mixes and discharges A liquid mainly composed of polyisocyanate, B liquid mainly composed of polyol, and liquefied carbon dioxide as a blowing agent supplied from a liquefied carbon dioxide container. ,
A supply pump for sending out the A liquid and the B liquid so as to have a predetermined discharge pressure;
Liquefied carbon dioxide as the liquefied carbon dioxide container or al onset foaming agent (excluding carbon dioxide comprising only the gas phase), the A liquid as a conveyance force the pressure difference between the pressure and the discharge pressure of the liquefied carbon dioxide container and An opening / closing valve that is provided in the middle of a supply pipe that supplies liquid B and that switches between supply and stop of liquefied carbon dioxide supplied through the supply pipe;
In order to control the supply amount of the liquid carbon dioxide, and the like the on-off valve at the time of driving the supply pump is in the open state, in conjunction with the feed pump to switch the opening and closing of the on-off valve the valve control means,
With
The valve control means includes
A movable member of the supply pump and a detection member provided in a fixed state with respect to the movable portion of the supply pump, and a detection member for detecting a drive of the detected member and transmitting a pump operation signal; ,
A polyurethane foam manufacturing apparatus, comprising: an operation control unit that switches and controls opening and closing of the on-off valve according to presence or absence of detection of a pump operation signal transmitted from the detection member. The operation control unit detects the pump operation signal to change the open / close valve from the closed state to the open state, and when the pump operation signal is not detected again within a predetermined time , the open / close valve is changed from the open state to the closed state. The apparatus for producing polyurethane foam according to claim 1. The supply pump includes a piston that sends out the liquid A and the liquid B by reciprocation,
The polyurethane foam manufacturing apparatus according to claim 1 or 2, wherein the detected members are arranged along an operation direction of the piston. The detection member is composed of a switch that transmits the pump operation signal when being pressed by being pressed;
The polyurethane foam manufacturing apparatus according to any one of claims 1 to 3, wherein the member to be detected includes a pressing member that presses the switch. The valve control means includes
A timer unit that counts an elapsed time after detecting the pump operation signal;
When the operation control unit detects the pump operation signal when the on-off valve is in the closed state, the operation control unit switches the on-off valve from the closed state to the open state, and when a predetermined time elapses without detecting the pump operation signal again. The polyurethane foam manufacturing apparatus according to claim 3 or 4, wherein the on-off valve is controlled to be in a closed state. The operation controller is
When the pump operation signal is detected when the on-off valve is in the closed state, the on-off valve is switched from the closed state to the open state, and when the pump operation signal is detected again before the predetermined time has elapsed, the on-off valve is maintained in the open state. resets the count of the timer section and, when not detected again the pumping signal before the predetermined time period elapses, which in the closed condition the closing valve from the open state, according to claim 5 Polyurethane foam manufacturing equipment. The detection member is composed of a switch that transmits the pump operation signal when being pressed by being pressed;
The detected member includes a pressing member that presses the switch,
The supply pump is
A piston for sending out the A liquid and the B liquid by reciprocating motion,
A pressing member holding member that extends in the driving direction of the piston and has a mounting region having the same dimensions as the stroke width of the piston;
With
3. The polyurethane foam manufacturing apparatus according to claim 1, wherein the pressing members are arranged at equal intervals in an attachment region of the pressing member holding member.   The polyurethane foam manufacturing apparatus according to claim 7, wherein the attachment region of the pressing member holding member is configured by a long hole. The supply pump includes a piston that sends out the liquid A and the liquid B by reciprocation,
The detected members are arranged along the operation direction of the piston,
The detection member is composed of a switch that transmits the pump operation signal when being pressed by being pressed;
The detected member includes a pressing member that presses the switch,
3. The polyurethane foam manufacturing apparatus according to claim 2 , wherein the operation control unit sets, as the predetermined time, a time determined based on a time obtained by dividing a half cycle of the piston by the number of the pressing members. .

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