JP7699897B2 - Additive mixing device and foamed resin molding manufacturing device - Google Patents

Description

This disclosure relates to an additive mixing device that adds and mixes additives into a liquid, and a foamed resin molding manufacturing device that includes the additive mixing device.

Conventionally, as this type of additive mixing device, a device in which an additive is introduced into a flow path through which a first liquid flows is known (see, for example, Patent Document 1).

JP 2016-50228 A (paragraph [0038] and FIG. 1)

However, there is a need to develop technology that can stabilize the mixture of the first liquid and the additive in the additive mixing device described above.

The additive mixing device according to the invention of aspect 1, which has been made to achieve the above object, is an additive mixing device that uses a supply device to introduce an additive into a communication flow path that connects a first position of a first flow path through which a first liquid flows and a second position downstream of the first position, and mixes the additive into the first liquid, and is equipped with a flow switching device that switches between a first flow state in which the first liquid flows more from the communication flow path to the first flow path from the first position and a second flow state in which the first liquid flows more from the first position to the communication flow path from the first flow path, and a control unit that controls the additive supply device and the flow switching device to repeat a cycle operation of switching from the second flow state to the first flow state, introducing the additive into the communication flow path, and then returning to the second flow state, and a control unit that controls the supply device and the flow switching device to repeat the cycle operation.

FIG. 1 is a schematic diagram showing an apparatus for producing a foamed resin molded product according to an embodiment of the present disclosure. Schematic diagram showing additive mixing device (A) is a side cross-sectional view of a cylinder piston device, and (B) is a cross-sectional view taken along the line A-A. Block diagram of additive mixing device Additive supply program flow chart 1A shows the state of the additive mixer before receiving a start signal from the first concentrate supply device and when switching to the first flow state. FIG. FIG. 1 shows the state of the additive mixer when (A) the downstream valve is closed and the injection valve is open, and (B) the piston is rising. FIG. 1 shows the state of the additive mixer when (A) the piston is rising and (B) the injection valve is closed and the downstream valve is open. FIG. 1 shows the additive mixer when (A) the piston is moving downwards and (B) when switching to the second flow state. FIG. 13 is a side cross-sectional view of a cylinder piston device according to another embodiment;

The foamed resin molded body manufacturing apparatus 10 having the additive mixing device 50 of the present disclosure will be described below with reference to Figures 1 to 9. The foamed resin molded body manufacturing apparatus 10 of this embodiment is a polyurethane foam manufacturing apparatus, and mixes a first liquid, which is a first urethane stock solution mainly composed of polyol, and a second liquid, which is a second urethane stock solution mainly composed of polyisocyanate, which are raw materials for polyurethane foam, on-site, for example, and sprays it onto a construction target to foam-mold. As shown in Figure 1, the foamed resin molded body manufacturing apparatus 10 has a first stock solution supplying device 11 that supplies the first liquid, a second stock solution supplying device 15 that supplies the second liquid, and a mixing and discharging section 70 that mixes and discharges the first liquid and the second liquid. In addition, an additive supplying device 20 is connected to the first stock solution supplying device 11, and an additive is supplied to the first liquid.

Here, the first liquid and the second liquid generate carbon dioxide by mixing, and this carbon dioxide forms a bubble structure in the urethane resin (chemical foaming). In this embodiment, the generation of the bubble structure is further promoted by adding a physical foaming agent as an additive. In this embodiment, liquefied carbon dioxide is used as the physical foaming agent, and foaming is performed by utilizing the vaporization of the liquefied carbon dioxide. In other words, the liquefied carbon dioxide needs to be kept in a pressurized state with suppressed vaporization until the first liquid and the second liquid start to react, and the first liquid also needs to be kept at a pressure equal to or higher than the vapor pressure of the liquefied carbon dioxide. In addition, by using liquefied carbon dioxide as a physical foaming agent, the cell diameter of the polyurethane foam is reduced, and the heat insulating effect is improved. In addition, since the initial foaming characteristics (foaming characteristics) are improved, it is possible to reduce the amount of raw materials used.

The first stock solution supplying device 11 has a first stock solution tank 12 that stores the first liquid, and a first flow path 14 that extends from the first stock solution tank 12 and communicates with the mixing and discharging section 70. The first stock solution supplying device 11 pumps a predetermined amount of the first liquid from the first stock solution tank 12 to the first flow path 14 using a first supply pump 13, and supplies it to the mixing and discharging section 70. The first supply pump 13 maintains the pressure P1 of the first liquid at, for example, 7 MPa. In this embodiment, the length of the first flow path 14 is 60 m to 150 m.

The second stock solution supplying device 15 has a configuration similar to that of the first stock solution supplying device 11, and includes a second stock solution tank 16 for storing the second liquid, and a second flow path 18 extending from the second stock solution tank 16 and communicating with the mixing and discharging section 70. The second stock solution supplying device 15 pumps a predetermined amount of the second liquid from the second stock solution tank 16 to the second flow path 18 by the second feed pump 17, and supplies it to the mixing and discharging section 70. In this embodiment, the second feed pump 17 maintains the pressure of the second liquid at 7 MPa, the same as the first liquid, but the pressure may be different from that of the first liquid.

The mixing and discharging unit 70 is a so-called discharging gun that mixes and discharges the first and second liquids, and has a trigger (not shown). When the trigger is pulled, the first and second liquids are mixed and simultaneously discharged from a nozzle (not shown). At this time, the pressure in the first flow path 14 and the second flow path 18 decreases, and the first feed pump 13 and the second feed pump 17 are operated. When the trigger is released, discharging stops and the first feed pump 13 and the second feed pump 17 are stopped. Since the first and second liquids start reacting when mixed, they are simultaneously discharged and sprayed onto the work target. When the reaction between the first and second liquids is completed, polyurethane foam is formed. The liquefied carbon dioxide added to the first liquid is vaporized by releasing the pressure immediately after discharging, and as described above, contributes to physical foaming. The mixing and discharging unit 70 corresponds to the "third position" in the claims.

Now, as shown in FIG. 1, the first flow path 14 of the first stock solution supply device 11 of this embodiment is provided with a communication flow path 19 that connects the first position 14A and the second position 14B downstream of the first position 14A. As a result, the first liquid delivered from the first stock solution tank 12 flows to the mixing and discharging section 70 through two routes: a route that passes through the communication flow path 19 from the first position 14A and returns to the first flow path 14 at the second position 14B, and a route that passes through the first flow path 14 directly without passing through the communication flow path 19. The additive supply device 20 described above is connected to this communication flow path 19. The additive mixing device 50 according to the present disclosure is composed of the communication flow path 19, the additive supply device 20, and the first flow path 14 between the first position 14A and the second position 14B.

As shown in FIG. 2, the additive supply device 20 has an additive storage section 22 that stores liquefied carbon dioxide, a cylinder piston device 40 that measures and discharges a fixed amount of liquefied carbon dioxide, and an additive introduction passage 23 that connects the additive storage section 22 and the cylinder piston device 40.

The additive storage section 22 includes a pressure vessel 21 for storing liquefied carbon dioxide and an insulated chamber 24 for housing the pressure vessel 21. The pressure vessel 21 maintains the liquefied carbon dioxide in a liquid phase at a preset first pressure. The insulated chamber 24 includes a temperature control device 26 having a cooler and a heater, and an output control unit (not shown) for controlling them. When the pressure detected by a pressure sensor 27P provided in the additive introduction passage 23 described later is less than the first pressure, the output control unit stops the cooler and operates the heater, and when the pressure detected by the pressure sensor 27P is greater than the first pressure, the output control unit stops the heater and operates the cooler, controlling the pressure of the liquefied carbon dioxide to be the first pressure. In this embodiment, the first pressure is 5.6 [MPa], and the temperature of the liquefied carbon dioxide at this time is 20 [°C].

The warming cabinet 24 is equipped with a temperature sensor (not shown), and the output control unit controls the cooler to stop to prevent overcooling when the temperature falls below a set temperature (20°C in this embodiment), and stops the heater to prevent overheating when the temperature exceeds the set temperature. The warming cabinet 24 corresponds to the "box" in the claims.

The heat-retaining chamber 24 is provided with a heat insulating material to maintain heat retention. The heat-retaining chamber 24 is also provided with a door (not shown) for inserting and removing the pressure vessel 21, and the door is provided with, for example, a trim seal to maintain airtightness.

The additive introduction passage 23 is connected to the supply port 21A of the pressure vessel 21, and a manifold 27 that constitutes part of the additive introduction passage 23 is disposed between the supply port 21A and the cylinder piston device 40. The manifold 27 includes branch pipes 23A and 23B that branch off from the additive introduction passage 23, a pressure sensor 27P, and a temperature sensor 27T.

Of the branch pipes 23A and 23B, the upstream branch pipe 23A is connected to a safety valve 28, and the downstream branch pipe 23B is connected to a blow valve 29. When the blow valve 29 is in an open state, it releases the liquefied carbon dioxide in the supply device 22. In this embodiment, the safety valve 28 is set to open at 9 MPa.

In this embodiment, the manifold 27 is provided with a cooling device (not shown). The cooling device cools the manifold 27 to a set temperature based on the temperature detected by the temperature sensor 27T. As described above, in this embodiment, the liquefied carbon dioxide is kept in liquid phase by the heat retention chamber 24, but the cooling device also prevents the liquefied carbon dioxide flowing through the additive introduction path 23 from evaporating before being introduced into the cylinder piston device 40.

Downstream of the manifold 27 in the additive introduction passage 23, an injection drive valve 30 and an injection check valve 31 are provided in this order from the manifold 27 side. The injection drive valve 30 is controlled to open and close by the control unit 60 (see FIG. 4). The injection check valve 31 prevents backflow of the first liquid, liquefied carbon dioxide, and the mixture of the first liquid and liquefied carbon dioxide from the cylinder piston device 40 to the additive storage section 22, and allows only flow from the additive storage section 22 to the cylinder piston device 40.

3(A) and 3(B), the cylinder piston device 40 includes a cylinder 41 and a piston 42 that reciprocates within the cylinder 41. The cylinder 41 includes a first intake port 41A, a second intake port 41B, and an exhaust port 43. The first intake port 41A is connected to the additive introduction passage 23, and the second intake port 41B and the exhaust port 43 are connected to the upstream and downstream sides of the communication flow passage 19 of the first concentrate supply device 11, respectively (see FIG. 2). Specifically, a pressure chamber 40A extending in the axial direction is formed within the cylinder 41, and the first intake port 41A, the second intake port 41B, and the exhaust port 43 communicate with a cross hole 40B that crosses one end of the pressure chamber 40A. The first intake port 41A, the second intake port 41B, and the exhaust port 43 correspond to the "device connection part" in the claims.

The piston 42 is in sliding contact with the inner circumferential surface of the pressure chamber 40A, and the tip of the piston 42 moves linearly between one end and the other end of the pressure chamber 40A. In detail, the piston 42 has a stepped structure in which the tip small diameter portion 45 protrudes from the tip of the large diameter portion 44, and a receiving chamber 46 that receives the large diameter portion 44 and communicates with the other end of the pressure chamber 40A is formed in the cylinder 41. In addition, the tip small diameter portion 45 has a step surface 45M that expands the diameter on the base end side at a position near the base end, and the tip side of the step surface 45M is inserted into a bush 80 fixed in the cylinder 41. The piston 42 is usually positioned at the lower end position (see Figures 3(A) and (B)) where the step surface 45M of the tip small diameter portion 45 abuts against the bush 80. Then, when the piston 42 rises from the lowering end position in a direction away from the cross hole 40B by a preset distance, it is positioned at the upper end position (see FIG. 8(B)).

In the cylinder piston device 40 of this embodiment, as described in detail later, when the piston 42 rises from the lowering end position to the upper end position, a predetermined amount of liquefied carbon dioxide is drawn into the cylinder 41 from the first intake port 41A. The axial lengths of the small diameter tip portion 45 and the pressure chamber 40A are set so that the tip surface 45M of the small diameter tip portion 45 is received in the pressure chamber 40A when the piston 42 is positioned at the upper end position. In this embodiment, an air cylinder is used as the cylinder piston device 40, and the stroke of the air cylinder is adjusted to change the stroke of the piston 42, thereby adjusting the amount of liquefied carbon dioxide added.

Here, in this embodiment, as described above, the second intake port 41B of the cylinder 41 is connected to the upstream side of the communication flow path 19 of the first raw liquid supply device 11, and the first liquid is introduced into the pressure chamber 40A of the cylinder 41 from the first position 14A of the first flow path 14. As a result, when the piston 42 rises from the lowering end position to the upper end position and a predetermined amount of liquefied carbon dioxide is sucked into the cylinder 41 from the first intake port 41A, the first liquid is mixed with the liquefied carbon dioxide in the pressure chamber 40A. Then, when the piston 42 descends from the upper end position to the lowering end position, the mixture in which the liquefied carbon dioxide is added to the first liquid is discharged from the discharge port 43. The mixture in which the liquefied carbon dioxide is added to the first liquid is supplied to the first flow path 14 at the second position 14B through the communication flow path 19 (see FIG. 2).

As shown in FIG. 2, downstream of the discharge port 43 in the communication flow path 19, a downstream check valve 32 and a downstream drive valve 33 are provided in this order from the discharge port 43 side. The downstream drive valve 33 is controlled to open and close by the control unit 60 (see FIG. 4), similar to the above-mentioned injection drive valve 30. The downstream check valve 32 prevents backflow of the first liquid from the first flow path 14 to the cylinder piston device 40 and the mixed liquid in which liquefied carbon dioxide is added to the first liquid, and allows only the flow from the cylinder piston device 40 to the first flow path 14. The downstream drive valve 33 and the downstream check valve 32 correspond to the "flow switching device" in the claims.

Also, as shown in FIG. 2, upstream of the second intake port 41B in the communication flow path 19, an upstream check valve 34 and an upstream drive valve 35 are provided in this order from the second intake port 41B side. The upstream drive valve 35 is controlled to open and close by the control unit 60 (see FIG. 4) in the same manner as the injection drive valve 30 and the downstream drive valve 33 described above. The upstream check valve 34 prevents backflow of the first liquid from the cylinder piston device 40 to the first flow path 14 and the mixed liquid in which liquefied carbon dioxide is added to the first liquid, and allows only the flow from the first flow path 14 to the cylinder piston device 40. The upstream drive valve 35 and the upstream check valve 34 correspond to the "flow switching device" in the claims.

As shown in FIG. 2, a manifold 36 that constitutes a part of the communication flow passage 19 is disposed upstream and downstream of the cylinder piston device 40 in the communication flow passage 19. The manifold 36 is provided with a pressure sensor 36P that detects the pressure downstream of the cylinder piston device 40 in the communication flow passage 19. The upstream check valve 34 and the upstream drive valve 35 are disposed downstream of the manifold 36 in the communication flow passage 19, and the downstream check valve 32 and the downstream drive valve 33 are disposed upstream of the manifold 36 in the communication flow passage 19.

As shown in FIG. 2, a first flow path shutoff valve 37 is provided between the first position 14A and the second position 14B in the first flow path 14. The first flow path shutoff valve 37 is controlled to open and close by the control unit 60 (see FIG. 4), similar to the injection drive valve 30, downstream drive valve 33, and upstream drive valve 35 described above. The first flow path shutoff valve 37 corresponds to the "flow switching device" in the claims.

Figure 4 shows the electrical configuration of the additive mixing device 50. As shown in the figure, the additive mixing device 50 is provided with a control unit 60 having a drive valve control unit 61, a cylinder piston control unit 62, and a receiving unit 63.

The cylinder piston control unit 62 drives and controls the cylinder piston device 40. Specifically, the cylinder piston control unit 62 drives the piston 42 via the drive circuit 66 based on the position of the piston 42 detected by the position sensor 67. The position sensor 67 is disposed in the cylinder piston device 40.

The valve control unit 61 controls the opening and closing of the first flow path shutoff valve 37, the upstream valve 35, the downstream valve 33, and the injection valve 30. Specifically, the valve control unit 61 opens and closes via the drive circuits 64A, 64B, 64C, and 64D based on the pressure signal detected by the pressure sensor 36P, i.e., the pressure P1 of the first liquid, and the position of the piston 42 detected by the position sensor 67.

In this embodiment, the first flow path shutoff valve 37, the upstream drive valve 35, the downstream drive valve 33, and the injection drive valve 30 are single-acting air-driven valves that purify the air supplied from an air supply source (not shown) through an air filter, air regulator, or air filter regulator, adjust the pressure to a predetermined level, and open and close in response to switching between supply and exhaust through an air solenoid valve (not shown). The first flow path shutoff valve 37 is a normally open valve, the upstream drive valve 35 is a normally closed valve, the downstream drive valve 33 is a normally open valve, and the injection drive valve 30 is a normally closed valve. The normally closed valve opens when air is supplied and closes when air is exhausted, and the normally open valve closes when air is supplied and opens when air is exhausted.

In detail, the drive valve control unit 61 controls the upstream drive valve 35 to be in a closed state when the first flow path shutoff valve 37 is in an open state, and controls the upstream drive valve 35 to be in an open state when the first flow path shutoff valve 37 is in a closed state. In other words, the first flow path shutoff valve 37 and the upstream drive valve 35 switch between a first flow state in which the first liquid is blocked from flowing from the first position 14A to the communication flow path 19 and flows through the first flow path 14, and a second flow state in which the first liquid is blocked from flowing from the first position 14A to the first flow path 14 and flows through the communication flow path 19. In this embodiment, the air pipe (not shown) connecting the air supply source and the upstream drive valve 35 branches off and is connected to the first flow path shutoff valve 37.

The valve control unit 61 also controls the downstream valve 33 to be open when the injection valve 30 is closed, and controls the downstream valve 33 to be closed when the injection valve 30 is open. In this embodiment, the air pipe connecting the air supply source and the injection valve 30 branches to connect the downstream valve 33.

The receiving unit 63 receives a permission signal to start supplying liquefied carbon dioxide from the first stock solution supplying device 11, which supplies the first liquid to the first flow path 14. In detail, as described above, pulling the trigger of the mixing and discharging unit 70 activates the first supply pump 13, so the first stock solution supplying device 11 detects the piston position using a sensor provided at the moving end of the piston of the first supply pump 13, and transmits a permission signal to start supplying liquefied carbon dioxide when the piston completes dispensing. The permission signal may be transmitted each time a certain amount of the first liquid is dispensed.

The control unit 60 has a temperature control unit (not shown) and receives an electrical signal corresponding to the temperature detected by the temperature sensor 27T, and controls the cooling device provided in the manifold 27 via a drive circuit (not shown).

Figure 5 shows the additive supply program PG1 executed by the control unit 60 when the additive supply device 20 supplies liquefied carbon dioxide. The additive supply program PG1 is executed when the additive supply device 20 is powered on. As shown in the figure, when the additive supply program PG1 is executed, the control unit 60 first performs an initial setting (S11). In this initial setting (S11), the upstream drive valve 35 is opened and the first flow path shutoff valve 37 is closed to set the flow of the first liquid to the second flow state, the injection drive valve 30 is closed and the downstream drive valve 33 is opened, and the piston 42 is positioned at the downward end position.

At this time, the first liquid flowing through the first flow path 14 flows entirely into the communication flow path 19 from the first position 14A. The first liquid is then introduced into the cylinder 41 from the second intake port 41B, passes through the communication flow path 19 from the exhaust port 43, and is returned to the first flow path 14 at the second position 14B. Note that the initial setting (S11) is executed only once when the power of the additive supply device 20 is turned on.

When the initial setting (S11) is completed, the control unit 60 judges whether or not a permission signal to start supplying liquefied carbon dioxide has been received from the first concentrate supply device 11 (S12). If a permission signal has not been received (No in S12), the control unit 60 makes this judgment (S12) again.

If a start signal has been received (Yes in S12), it is then determined whether the pressure detected by the pressure sensor 36P, i.e., the pressure P1 of the first liquid flowing through the first flow path 14 (e.g., 7 MPa) is higher than the set pressure (S13). Here, the set pressure is set to be the same as the first pressure of the liquefied carbon dioxide stored in the pressure vessel 21 (e.g., 5.6 MPa). If the detected pressure is equal to or lower than the set pressure (No in S13), the process returns to step S12.

If the detected pressure is higher than the set pressure (Yes in S13), the first flow path shutoff valve 37 is opened and then the upstream drive valve 35 is closed (S14) to change the flow of the first liquid from the second flow state to the first flow state. When switching the flow of the first liquid from the second flow state to the first flow state, the control unit 60 first opens the first flow path shutoff valve 37 and then controls the upstream drive valve 35 to the closed state.

Then, the downstream drive valve 33 is closed and the injection drive valve 30 is opened (S15). Next, the piston 42 is raised to the upper end position to perform a suction operation (S16). The distance from the lower end position to the upper end position is set based on the pressure P1 of the first liquid in the first flow path 14 and the pressure P2 of the liquefied carbon dioxide.

When the piston 42 reaches the upper end position, the injection drive valve 30 is closed and then the downstream drive valve 33 is opened (S17), and then the piston 42 is lowered to the lower end position to perform a discharge operation (S18). When the piston 42 reaches the lower end position, the upstream drive valve 35 is opened and then the first flow path shutoff valve 37 is closed (S19), changing the flow of the first liquid from the first flow state to the second flow state, and the process returns to step S12. When switching the flow of the first liquid from the first flow state to the second flow state, the control unit 60 first controls the upstream drive valve 35 to the open state and then controls the first flow path shutoff valve 37 to the closed state.

6 to 9 show the state of the additive mixing device 50 when the control unit 60 is executing the additive supply program PG1. Before the control unit 60 receives an enable signal from the first stock solution supply device 11 (step S11), as shown in FIG. 6 (A), the flow of the first liquid is in a second flow state in which the upstream drive valve 35 is open and the first flow path shutoff valve 37 is closed, and the injection drive valve 30 is closed, the downstream drive valve 33 is open, and the piston 42 is located at the lowering end position. At this time, the internal pressure P of the pressure chamber 40A of the cylinder 41 becomes equal to the pressure P1 (7 [MPa]) of the first liquid in the first flow path 14, and both the upstream check valve 34 and the downstream check valve 32 are in an open state. As a result, the first liquid flowing from the first position 14A of the first flow path 14 to the communication flow path 19 is introduced into the cylinder 41 from the second suction port 41B.

If the internal pressure P of the pressure chamber 40A is lower than the pressure P1 in the first flow path 14, the downstream check valve 32 closes and the upstream check valve 34 opens, so that the internal pressure P in the pressure chamber 40A eventually becomes equal to the pressure P1 in the first flow path 14, and both the upstream check valve 34 and the downstream check valve 32 open. Also, if the internal pressure P of the pressure chamber 40A is higher than the pressure P1 in the first flow path 14, the upstream check valve 34 closes and the downstream check valve 32 opens, so that the internal pressure P in the pressure chamber 40A eventually becomes equal to the pressure P1 in the first flow path 14, and both the upstream check valve 34 and the downstream check valve 32 open.

Then, if the control unit 60 receives an authorization signal from the first stock solution supply device 11 in step S12 of the additive supply program PG1 and the internal pressure P of the pressure chamber 40A is higher than the first pressure (5.6 MPa) (YES in S13), it executes step S14. Then, as shown in FIG. 6B, the flow of the first liquid becomes the first flow state in which the first flow path shutoff valve 37 is open and the upstream drive valve 35 is closed. At this time, the internal pressure P of the pressure chamber 40A remains equal to the pressure P1 in the first flow path 14.

Here, in the first flow state, the downstream drive valve 33 is open, which is a state in which the upstream drive valve 35 and the downstream check valve 32 block the communication flow path 19 from the first flow path 14 so that the first liquid does not flow into the pressure chamber 40A from both the first position 14A and the second position 14B (hereinafter referred to as the "first closed state"), and a state in which only discharge from the pressure chamber 40A to the second position 14B is permitted (hereinafter referred to as the "second closed state").

Next, when the control unit 60 executes step S15 of the additive supply program PG1, the downstream drive valve 33 closes and the injection drive valve 30 opens, as shown in FIG. 7(A). Here, the internal pressure P of the pressure chamber 40A is still equal to the pressure P1 in the first flow path 14, and the pressure P2 of the liquefied carbon dioxide is adjusted to a first pressure lower than the pressure P1 in the first flow path 14 by the temperature adjustment device 26 (see FIG. 2) provided in the additive storage unit 22, so the injection check valve 31 is closed. At this time, since the downstream drive valve 33 is closed, only the first closed state is established, and the second closed state is not established, and discharge from the pressure chamber 40A side to the second position 14B side is not possible.

Next, when the control unit 60 executes step S16 of the additive supply program PG1, as shown in FIG. 7(B), the piston 42 starts to rise, and on the way to the rising end position, the internal pressure P of the pressure chamber 40A decreases, and the internal pressure P of the pressure chamber 40A becomes equal to the pressure P2 of the liquefied carbon dioxide, and an equilibrium state is reached. From there, as shown in FIG. 8(A), the piston 42 continues to rise further, and the injection check valve 31 opens while the piston 42 reaches the rising end position, and liquefied carbon dioxide is sucked into the pressure chamber 40A from the first intake port 41A, and the liquefied carbon dioxide is mixed with the first liquid in the pressure chamber 40A. Then, as shown in FIG. 8(B), when the piston 42 rises to the rising end position, a predetermined amount of liquefied carbon dioxide is sucked into the pressure chamber 40A.

Next, when the control unit 60 executes step S17 of the additive supply program PG1, the injection valve 30 closes and the downstream valve 33 opens, as shown in FIG. 8(B). At this time, the internal pressure P of the pressure chamber 40A is equal to the pressure P2 of the liquefied carbon dioxide, so the downstream check valve 32 remains closed, but the downstream valve 33 is open, so the first closed state and the second closed state are established.

Therefore, when the control unit 60 executes step S18 of the additive supply program PG1, as shown in FIG. 9(A), the piston 42 descends, the internal pressure P of the pressure chamber 40A rises, and when the internal pressure P of the pressure chamber 40A becomes equal to the pressure P1 in the first flow path 14, the downstream check valve 32 opens and the mixture in which liquefied carbon dioxide has been added to the first liquid in the pressure chamber 40A is discharged from the outlet 43.

Then, when the piston 42 descends to the descending end position, as shown in FIG. 9(B), the control unit 60 executes step S19 of the foaming agent program PG1, the upstream drive valve 35 opens, the first flow path shutoff valve 37 closes, and the flow of the first liquid returns from the first flow state to the second flow state. As a result, the first liquid in the communication flow path 19 and the mixed liquid in which liquefied carbon dioxide has been added to the first liquid are pushed out and supplied to the first flow path 14 at the second position 14B.

This concludes the explanation of the configuration of the foamed resin molded body manufacturing apparatus 10 equipped with the additive supply device 20 of this embodiment. Next, the effects of the foamed resin molded body manufacturing apparatus 10 will be explained.

In this embodiment, a communication flow path 19 that connects a first position 14A of the first flow path 14 to a second position 14B downstream of the first position 14A is branched off from the first flow path 14, and liquefied carbon dioxide is introduced into the communication flow path 19 from an additive supply device 20. In this embodiment, the first liquid can be switched between a first flow state in which the first liquid is blocked from flowing from the first position 14A to the communication flow path 19 and flows into the first flow path 14, and a second flow state in which the first liquid is blocked from flowing from the first position 14A to the first flow path 14 and flows into the communication flow path 19. Then, a cycle operation of switching from the second flow state to the first flow state, introducing liquefied carbon dioxide into the communication flow path 19, and then returning to the second flow state is repeated.

Here, in a conventional configuration that does not have a second flow state that blocks the flow from the first position 14A to the first flow path 14, even if the first liquid is introduced into the communication flow path 19 after liquefied carbon dioxide is introduced into the communication flow path 19, a portion of the first liquid branches off at the first position 14A and flows directly into the first flow path 14, so the flow rate and pressure of the first liquid flowing through the communication flow path 19 are not constant. As a result, the flow rate and pressure of the first liquid flowing through the communication flow path 19 change, and the introduced liquefied carbon dioxide remains in the communication flow path 19, which can cause the amount of carbon dioxide supplied to the first flow path 14 to become unstable.

In contrast, in this embodiment, a second flow state is provided, and the flow of the first liquid is changed to the second flow state each time liquefied carbon dioxide is added to the communication flow path 19, so that the added liquefied carbon dioxide can be pushed out of the communication flow path 19 and supplied to the first flow path 14. This prevents liquefied carbon dioxide from remaining in the communication flow path 19 for an extended period of time, and stabilizes the degree of mixing between the first liquid and the liquefied carbon dioxide.

In addition, when the additive supply device 20 supplies liquefied carbon dioxide, in this embodiment, the cylinder piston device 40 is provided and connected to the communication flow path 19 and the additive introduction path 23 that supplies liquefied carbon dioxide, and the first liquid is introduced into the pressure chamber 40A of the cylinder 41 of the cylinder piston device 40 in the second flow state, and then the first flow state is established, and the liquefied carbon dioxide is sucked into the pressure chamber 40A by the suction operation of the cylinder piston device 40, and the liquefied carbon dioxide is discharged from the pressure chamber 40A to the communication flow path 19 together with the first liquid by the discharge operation. Here, in this embodiment, when the internal pressure P of the pressure chamber 40A is higher than the pressure P2 of the liquefied carbon dioxide controlled to the first pressure that suppresses evaporation, the suction operation of the cylinder piston device 40 is established in the first flow state. This makes it possible to bring the internal pressure P of the pressure chamber 40A when the suction operation is performed close to the pressure P2 of the liquefied carbon dioxide, and it is possible to suppress evaporation when the liquefied carbon dioxide is sucked in and stabilize the supply amount of liquefied carbon dioxide. In addition, liquefied carbon dioxide is supplied when the internal pressure P of the pressure chamber 40A is higher than the pressure P2 of the liquefied carbon dioxide, which prevents excessive liquefied carbon dioxide from being drawn into the pressure chamber 40A, thereby stabilizing the amount of liquefied carbon dioxide supplied and stabilizing the degree of mixing between the first liquid and the liquefied carbon dioxide.

In this embodiment, the first flow state and the second flow state are switched by opening and closing the first flow path shutoff valve 37 provided between the first position 14A and the second position 14B of the first flow path 14 and the upstream drive valve 35 provided upstream of the cylinder piston device 40 in the communication flow path 19. When switching to the first flow state, the control unit 60 controls the first flow path shutoff valve 37 to open first and then close the upstream drive valve 35, and when switching to the second flow state, the control unit 60 controls the first flow path shutoff valve 37 to open first and then close the upstream drive valve 35. This prevents both flow paths from being closed and blocking the first flow path 14.

In this embodiment, a downstream check valve 32 that allows only discharge from the pressure chamber 40A to the second position 14B is provided on the downstream side of the cylinder piston device 40 in the communication flow path 19. As a result, when the upstream drive valve 35 is closed in the first flow state, the communication flow path 19 can be switched between a first closed state in which the communication flow path 19 is blocked from the first flow path 14 so that the first liquid and the mixture of the first liquid and liquefied carbon dioxide are not allowed to flow into the pressure chamber 40A from both the first position 14A and the second position 14B, and a second closed state that allows only discharge from the pressure chamber 40A to the second position 14B. The downstream check valve 32 and the upstream drive valve 35 can prevent the first liquid and the mixture of the first liquid and liquefied carbon dioxide from flowing into the pressure chamber 40A from both the first position 14A and the second position 14B when the internal pressure P of the pressure chamber 40A is lowered by the suction operation of the cylinder piston device 40, and can discharge the mixture of the first liquid and liquefied carbon dioxide to the second position 14B when the internal pressure P of the pressure chamber 40A is higher by the discharge operation of the cylinder piston device 40.

Furthermore, in this embodiment, a downstream drive valve 33 is provided downstream of the downstream check valve 32 in the communication flow path 19, and the downstream drive valve 33 is closed during the suction operation of the cylinder piston device 40, and the downstream drive valve 33 is controlled to be open during the discharge operation of the cylinder piston device 40. As a result, during the suction operation of the cylinder piston device 40, only the first closed state is established, and discharge from the pressure chamber 40A side to the second position 14B side is also suppressed. As a result, when the internal pressure P of the pressure chamber 40A becomes lower than the pressure P1 of the first flow path 14, it is possible to prevent the first liquid and the mixed liquid in which liquefied carbon dioxide is added to the first liquid from flowing from the second position 14B side to the pressure chamber 40A side, and when the pressure P1 of the first flow path 14 becomes lower than the internal pressure P of the pressure chamber 40A, it is possible to prevent excess additive from flowing out to the second position 14B side. In other words, when liquefied carbon dioxide is drawn into the pressure chamber 40A, the upstream valve 35 and the downstream valve 33 act as shutoff valves that shut off the communication flow path 19 from the first flow path 14. The upstream valve 35 and the downstream valve 33 correspond to the "communication flow path shutoff valve" in the claims.

Moreover, the additive introduction passage 23 is provided with an injection drive valve 30, which is controlled to be open only during the suction operation of the cylinder piston device 40. This also makes it possible to prevent the liquefied carbon dioxide from flowing out excessively toward the second position 14B. Therefore, in the additive mixing device 50 of this embodiment, liquefied carbon dioxide can be supplied quantitatively by the suction operation of the cylinder piston device 40 without being affected by the pressure P1 of the first flow path 14, and the mixing condition of the first liquid and the liquefied carbon dioxide can be stabilized.

In this embodiment, the pressure vessel 21 for storing the liquefied carbon dioxide is stored in a thermal storage 24 equipped with a temperature control device 26 having a cooler and a heater, and the pressure P2 of the liquefied carbon dioxide is adjusted to the first pressure. Here, the foamed resin molded body manufacturing apparatus 10 of this embodiment is transported to a construction site for use, and the environment in which it is installed varies depending on the region, climate, etc. Moreover, even at the same site, the temperature changes from moment to moment during construction in a day. In particular, the pressure of liquefied carbon dioxide changes widely with respect to temperature, and in order to always manufacture the same polyurethane foam, it is necessary to adjust the stroke of the piston 42 according to the pressure P2 of the liquefied carbon dioxide and vary the supply amount of liquefied carbon dioxide. However, it is difficult to adjust the supply amount of liquefied carbon dioxide to match the actual temperature, and the mixing condition of the first liquid and the liquefied carbon dioxide cannot be stabilized. Conventionally, a regulator was attached to the pressure vessel 21 to adjust the pressure reduction, but it is difficult to adjust due to problems such as the frequency of adjustment and the effect of the supply pressure.

In contrast, in this embodiment, the temperature is controlled to be constant by adjusting the pressure P2 of the liquefied carbon dioxide to the first pressure by controlling the cooler and heater of the temperature adjustment device 26 provided in the thermal storage 24. This makes it possible to suppress changes in the pressure P2 that accompany temperature changes due to the installation environment of the pressure vessel 21, eliminating the need for a regulator and regulator adjustment, and improving operability. Furthermore, by controlling the pressure P2 of the liquefied carbon dioxide supplied to the cylinder piston device 40 to be constant, it is also unnecessary to adjust the stroke of the piston 42, and the degree of mixing of the first liquid and the liquefied carbon dioxide can be stabilized.

[Other embodiments]
(1) In the above embodiment, the first flow path shut-off valve 37 and the upstream drive valve 35 were provided to switch the flow of the first liquid between the first flow state and the second flow state. However, a three-way valve may be provided at the first position 14A, which is the branch point between the first flow path 14 and the communication flow path 19, to switch between the first flow state and the second flow state.

(2) In the above embodiment, the first flow path shutoff valve 37 and the upstream drive valve 35 are provided to switch the flow of the first liquid between the first flow state and the second flow state. Instead of the first flow path shutoff valve 37, a flow control valve may be provided between the first position 14A and the second position 14B in the first flow path 14, and the opening degree of the flow control valve may be adjusted to switch between the first flow state in which more of the first liquid flows from the first position 14A to the first flow path 14 than the communication flow path 19, and the second flow state in which more of the first liquid flows from the first position 14A to the communication flow path 19 than the first flow path 14. This also makes it possible to introduce liquefied carbon dioxide into the communication flow path 19 in the first flow state, and then to push the added liquefied carbon dioxide out of the communication flow path 19 by switching to the second flow state. The flow control valve corresponds to the "first flow path throttle valve" in the claims.

(3) In the above embodiment, the first flow path shutoff valve 37, the upstream valve 35, the downstream valve 33, and the injection valve 30 were air-driven valves, but they may be hydraulically driven valves or solenoid valves.

(4) The downstream drive valve 33 does not have to be provided. Even if the downstream drive valve 33 is not provided, the downstream check valve 32 that only allows discharge from the cylinder piston device 40 to the second position 14B side is provided. Therefore, when the cylinder piston device 40 is in the suction operation, even if the internal pressure P of the pressure chamber 40A becomes low due to the first closed state, the communication flow path 19 can be blocked from the first flow path 14 so that the first liquid and the mixed liquid in which liquefied carbon dioxide has been added to the first liquid do not flow in from the second position 14B side.

(5) In the above embodiment, the liquefied carbon dioxide was adjusted to the first pressure by controlling the temperature adjustment device 26 equipped with both a cooler and a heater. However, the temperature adjustment device 26 may be configured to be equipped with only one of a cooler and a heater.

(6) In the above embodiment, the pressure vessel 21 was stored together with the temperature adjustment device 26 in the heat-retaining cabinet 24, but instead of the heat-retaining cabinet 24, a cover may be provided to cover the pressure vessel 21 and the temperature adjustment device 26.

(7) In the above embodiment, the position sensor 67 is provided in the cylinder piston device 40, and the position sensor 67 detects the position of the piston 42, and the control unit 60 executes steps S14 to S19 of the additive supply program PG1. However, a configuration may be adopted in which the position sensor 67 is not provided, and steps S14 to S19 are executed by program control using a timer. With this configuration, it is possible to avoid the device being stopped or having to be adjusted due to the position sensor 67 being misaligned or disconnected.

(8) In the above embodiment, the configuration was provided with both the injection check valve 31 and the injection drive valve 30, but the configuration may be provided with only the injection drive valve 30.

In addition, in the above embodiment, the configuration includes both the upstream check valve 34 and the upstream drive valve 35, but the configuration may include only the upstream drive valve 35.

In addition, in the above embodiment, the configuration includes both the downstream check valve 32 and the downstream valve 33, but the configuration may include only the downstream valve 33.

(9) In the above embodiment, the manifold 27 is equipped with a cooling device, but it does not have to be equipped with a cooling device.

(10) In the above embodiment, the pressure sensor 36P was configured to detect the pressure downstream of the communication flow path 19, but it may also be configured to detect the pressure upstream of the communication flow path 19.

(11) In the above embodiment, the cylinder 41 is provided with the first intake port 41A, the second intake port 41B, and the exhaust port 43, which are connected to the additive introduction passage 23, the upstream side of the communication flow passage 19, and the downstream side of the communication flow passage 19, respectively, and the liquefied carbon dioxide is sucked into the pressure chamber 40A of the cylinder 41 by the suction action of the cylinder piston device 40. However, the first intake port 41A may be provided in the communication flow passage 19 as shown in FIG. 10, instead of being provided in the cylinder 41, so that when the piston 42 rises and liquefied carbon dioxide is sucked in from the first intake port 41A, it is not sucked into the pressure chamber 40A. With this configuration, the first liquid introduced into the communication flow passage 19 can be mixed with the liquefied carbon dioxide. In FIG. 10, the first intake port 41A is provided upstream of the cylinder piston device 40 in the communication flow path 19, between the upstream check valve 34 and the second intake port 41B, but it may be provided downstream of the cylinder piston device 40 in the communication flow path 19, between the exhaust port 43 and the downstream check valve 32.

(12) In the above embodiment, a sensor may be provided to detect the opening and closing of the injection check valve 31, and when raising the piston 42, the piston 42 may be raised a set distance from when the injection check valve 31 opens.

(13) In the above embodiment, an air cylinder was used as the cylinder piston device 40, but an electric actuator, an electric cylinder, etc. may also be used. In this case, the amount of liquefied carbon dioxide added can be adjusted by numerically controlling the stroke.

(14) In the above embodiment, liquefied carbon dioxide as an additive is mixed into the first liquid, which is a first urethane stock solution mainly composed of polyol. However, it may be mixed into the second liquid, which is a first urethane stock solution mainly composed of polyisocyanate, or it may be mixed into both the first liquid and the second liquid.

(15) In the above embodiment, the foamed resin molding manufacturing apparatus 10 is a two-liquid mixing type urethane foam manufacturing apparatus, but it may be a one-liquid type urethane foam manufacturing apparatus. In this case, the second stock solution tank 16 is not provided, and the first and second liquids may be stored in the first stock solution tank 12.

(16) In the above embodiment, the foamed resin molding manufacturing apparatus 10 was a polyurethane foam manufacturing apparatus, but it is not limited to this and may be, for example, a polyisocyanurate foam, polyester foam, epoxy foam, acrylic foam, phenol foam, melamine formaldehyde foam, etc.

(17) In the above embodiment, liquefied carbon dioxide was used as the additive for the physical foaming agent, but it may also be an inert gas such as fluorocarbon or HFO (hydrofluoroolefin).

(18) In the above embodiment, the additive was a physical foaming agent, but it is not limited thereto and may be a foam stabilizer, a flame retardant, a viscosity reducer, a moisture absorbent, a cross-linking agent, or the like. These may be used alone or in combination of two or more. When the additive is a physical foaming agent, it is necessary to hold the additive at a pressure that suppresses vaporization as in the above embodiment and to pressurize the first liquid into which the additive is added to a pressure higher than the pressure of the additive, but if the additive does not vaporize, pressurization of the first liquid to suppress vaporization is not necessary.

In addition, although this specification and drawings disclose specific examples of the technology included in the scope of the claims, the technology described in the claims is not limited to these specific examples, but includes various modifications and variations of the specific examples, as well as parts of the specific examples taken alone.
<Additional Notes>
The following describes the group of features extracted from the above embodiment, while indicating effects, etc., as necessary. Note that, in the following, for ease of understanding, the corresponding configurations in the above embodiment are appropriately indicated in parentheses, but the present invention is not limited to the specific configurations indicated in parentheses.

For example, the following features 1 to 15 relate to an "additive mixing device for adding and mixing an additive into a first liquid, and a foamed resin molding manufacturing device equipped with the same," and can be considered to have been made in response to the problem that "there is a demand for the development of technology for stabilizing the mixing condition of the first liquid and the additive in the additive mixing device described above," in relation to the background art that "conventionally, as this type of additive mixing device, an additive is added into a flow path through which the first liquid flows (see, for example, JP 2016-50228 A (paragraph [0038] and FIG. 1)."

[Feature 1]
An additive mixing device that uses an additive supply device to introduce an additive into a communication flow path that connects a first position of a first flow path through which a first liquid flows and a second position downstream of the first position, and mixes the additive into the first liquid,
a flow switching device that switches between a first flow state in which the first liquid flows more into the first flow path than into the communication flow path from the first position and a second flow state in which the first liquid flows more into the communication flow path than into the first flow path from the first position;
and a control unit that controls the additive supply device and the flow switching device so as to repeat a cycle of switching from the second flow state to the first flow state, introducing the additive into the communication flow path, and then returning to the second flow state.

In feature 1, a communication flow path is provided in a first flow path through which the first liquid flows, and connects a first position of the first flow path to a second position downstream of the first position, and an additive is introduced from an additive supply device into the communication flow path. In the present disclosure, the flow switching device can switch the first liquid between a first flow state in which more of the first liquid flows into the first flow path than the communication flow path, and a second flow state in which more of the first liquid flows into the communication flow path than the first flow path, and a cycle operation of switching from the second flow state to the first flow state, introducing an additive into the communication flow path, and then returning to the second flow state is repeated. This allows the additive introduced into the communication flow path to be pushed out of the communication flow path and supplied to the first flow path every cycle. Therefore, it is possible to prevent the additive from remaining in the communication flow path for a long time, and to stabilize the mixing state of the first liquid and the additive.
[Feature 2]
The additive is a liquid physical foaming agent, and is injected into the communication flow path by the additive supply device at a pressure that suppresses vaporization,
2. The additive mixing device according to claim 1, wherein the first liquid is caused to flow through the first flow passage and the communication flow passage at a pressure that suppresses vaporization of the additive.

In feature 2, the additive is a liquid physical foaming agent, and is injected into the connecting flow path by the additive supply device at a pressure that suppresses vaporization, while the first liquid is caused to flow through the first flow path and the connecting flow path at a pressure that suppresses vaporization of the additive. This makes it possible to suppress vaporization of the additive when it is injected into the connecting flow path, thereby stabilizing the supply amount of the additive.

[Feature 3]
a pressure vessel capable of storing the additive in a pressurized state in which evaporation of the additive is suppressed and supplying the additive to the communication flow path;
A temperature control device having one or both of a heater and a cooler for heating and cooling the pressure vessel;
a pressure sensor for detecting a pressure of the additive discharged from the pressure vessel;
and an output control unit that controls an output of the temperature adjustment device so that the pressure detected by the pressure sensor becomes a first pressure that is preset as a pressure that suppresses evaporation of the additive.

In feature 3, the pressure vessel storing the additive is heated or cooled based on the value of a pressure sensor for detecting the pressure of the additive, and the pressure of the additive is adjusted to a first pressure that is preset as a pressure that suppresses vaporization. This makes it possible to suppress changes in the pressure of the additive that accompany temperature changes and control it to a constant pressure, suppressing fluctuations in the supply amount of the additive input to the communication flow path and stabilizing the mixing condition of the first liquid and the additive.

[Feature 4]
The additive mixing apparatus according to Feature 3, wherein the temperature control device has a box that houses the pressure vessel and heats or cools the inside of the box.

[Feature 5]
The additive mixing device according to any one of features 1 to 4, wherein the flow switching device includes a communication flow path shutoff valve that shuts off the communication flow path from the first flow path in response to an abnormality in pressure drop in the first flow path or the communication flow path.

In feature 5, the flow switching device includes a communication flow path shutoff valve that shuts off the communication flow path from the first flow path in response to an abnormality in the pressure drop in the first flow path or the communication flow path, thereby preventing the first liquid from flowing into the communication flow path from the first flow path and preventing excess additive from flowing out of the communication flow path into the first flow path, thereby stabilizing the mixing of the first liquid and the additive.

[Feature 6]
The additive is a liquid physical foaming agent,
the additive supply device includes a pressure vessel that stores the additive at a first pressure that is preset as a pressure for suppressing vaporization of the additive, an injection on-off valve that is provided between the pressure vessel and the communication flow path, and a cylinder-piston device that draws in a fixed amount of liquid from the communication flow path and then discharges the liquid into the communication flow path,
the first liquid is caused to flow through the first flow path and the communication flow path at a pressure equal to or greater than the first pressure;
the flow switching device is switchable between a first closed state in which the communication flow path is blocked from the first flow path so that the first liquid does not flow into an apparatus connection part of the communication flow path to which the additive supply device is connected from both sides of the first position and the second position, and a second closed state in which only discharge from the apparatus connection part to the second position is permitted, in the first flow state;
The additive mixing device according to any one of features 1 to 5, wherein the control unit controls the additive supply device and the flow switching device so as to open the injection on-off valve in the first flow state and the first closed state to cause the cylinder piston device to perform a suction operation, and then close the injection on-off valve in the first flow state and the second closed state to cause the cylinder piston device to perform a discharge operation, and then switch to the second flow state.

According to feature 6, when the additive is introduced into the communication flow path by the suction operation of the cylinder piston device of the additive supply device, the first closed state is set so that the first liquid does not flow into the device connection part of the additive supply device from both the first position and the second position, so that even if the pressure of the device connection part is reduced by the suction operation, the first liquid can be prevented from flowing from the first flow path to the device connection part. Then, when the cylinder piston device performs the discharge operation, the second closed state is set so that discharge from the device connection part to the second position side is permitted, so that the mixed liquid in which the additive is added to the first liquid can be discharged to the second position side. Moreover, the injection opening and closing valve provided between the pressure vessel that stores the additive and the communication flow path is in an open state when the suction operation is performed in the first closed state, and in a closed state when the suction operation is performed in the second closed state, so that it is also possible to prevent excess additive from flowing out of the pressure vessel into the first flow path.

[Feature 7]
The additive mixing apparatus according to feature 6, wherein the flow switching device is disposed in the communication flow path upstream of the apparatus connection portion and includes an upstream valve that is driven to open and close in response to a command from the control portion.

In feature 7, an upstream valve that is driven to open and close in response to a command from the control unit is disposed in the communication flow path upstream of the device connection part, so that it is possible to switch between the first flow state and the second flow state by opening and closing the upstream valve. Note that an upstream check valve that allows only flow from the first position to the communication flow path may be provided in the communication flow path between the upstream valve and the device connection part.

[Feature 8]
The additive mixing apparatus according to feature 6 or 7, wherein the flow switching device is disposed in the communication flow path downstream of the device connection portion and includes a downstream check valve that allows only a flow from the communication flow path to the first flow path.

In feature 8, a downstream check valve that allows only flow from the communication flow path to the first flow path is disposed downstream of the device connection part in the communication flow path, making it possible to switch between a first closed state that prevents the first liquid from flowing in from the second position and a second closed state that allows discharge from the device connection part to the second position.

[Feature 9]
The injection on-off valve is an injection drive valve that is driven to open and close in response to a command from the control unit,
9. The additive mixing device according to any one of features 6 to 8, wherein the control unit controls the injection drive valve to an open state only when the cylinder piston device is caused to perform a suction operation.

Feature 9 makes it possible to prevent excess additive from flowing into the first flow path when an abnormality occurs such that the pressure in the first flow path is lower than the pressure in the connecting flow path.

[Feature 10]
the flow switching device is disposed in the communication flow path downstream of the device connection portion, and includes a downstream valve that is driven to open and close in response to a command from the control portion,
10. The additive mixing device according to any one of features 6 to 9, wherein the control unit controls the downstream drive valve to an open state only when the injection on-off valve is in a closed state.

In feature 10, the communication flow path is provided downstream of the device connection part with a downstream valve that is driven to open and close in response to a command from the control part, and is controlled to be open only when the injection on-off valve is closed. Here, for example, if the pressure in the first flow path falls below the pressure in the communication flow path, an excessive amount of additive may flow into the first flow path. However, since the downstream valve is closed when the injection on-off valve is open, the additive is not affected by the pressure in the first flow path and excess additive can be prevented from flowing into the first flow path.

[Feature 11]
The additive mixing device according to any one of features 5 to 9, wherein the flow switching device includes a first flow path shutoff valve that shuts off the flow of the first liquid from the first position to the first flow path in the second flow state.

In feature 11, a first flow path shutoff valve is disposed to shut off the flow of the first liquid from the first position to the first flow path in the second flow state, so that the first flow state and the second flow state can be switched by opening and closing the first flow path shutoff valve. In addition, by providing both the first flow path shutoff valve and the upstream drive valve, for example, when switching from the second flow state in which the first liquid flows through the connecting flow path with the first flow path shutoff valve closed and the upstream drive valve open to the first flow state in which the first liquid flows through the first flow path, by first opening the first flow path shutoff valve and then closing the upstream drive valve, it is possible to prevent both flow paths from being closed and the first flow path being blocked.

[Feature 12]
The additive mixing device according to any one of features 6 to 10, wherein the flow switching device includes a first flow path throttle valve that throttles the flow of the first liquid from the first position to the first flow path when switching from the first flow state to the second flow state.

Feature 12 is provided with a first flow path throttle valve that throttles the flow of the first liquid from the first position to the first flow path when switching from the first flow state to the second flow state, and the first liquid is always flowing through the first flow path. This makes it possible to suppress changes in the pressure of the first liquid at the first and second positions in the first flow path, and to stabilize the mixing of the first liquid and the additive.

[Feature 13]
An additive mixing device according to any one of features 6 to 12;
a second flow path connected to a third position downstream of the second position of the first flow path, through which a second liquid flows,
A foamed resin molded body manufacturing apparatus for producing a foamed resin molded body from the first liquid containing the additive and the second liquid.

[Feature 14]
The foamed resin molded body manufacturing apparatus according to feature 13, wherein one of the first liquid and the second liquid is a first urethane stock solution containing a polyol as a main component, and the other is a second urethane stock solution containing a polyisocyanate as a main component, and a polyurethane foam is produced from the first liquid containing the additive and the second liquid.

[Feature 15]
a first feed pump configured to feed the first liquid to the first flow path;
a second feed pump configured to feed the second liquid to the second flow path;
a discharge gun provided at an end of the first flow path and having a trigger for operating whether or not to discharge a mixed liquid of the first liquid and the second liquid,
the first feed pump and the second feed pump are activated or stopped due to operation of the trigger;
15. The foamed resin molded body manufacturing apparatus according to feature 13 or 14, wherein the control unit controls the additive supply device and the flow switching device to be linked to the first feed pump and the second feed pump.

According to feature 15, when the first delivery pump is actuated by operating the trigger and the first liquid is delivered to the first flow path, it becomes possible to supply the additive.

Note that although specific examples of the technology included in the scope of the claims are disclosed in this specification and drawings, the technology described in the claims is not limited to these specific examples, but includes various modifications and variations of the specific examples, as well as parts of the specific examples taken separately.

REFERENCE SIGNS LIST 10: Apparatus for manufacturing foamed resin molded body 11: First raw liquid supply device 13: First feed pump 14: First flow path 14A: First position 14B: Second position 15: Second raw liquid supply device 17: Second feed pump 18: Second flow path 19: Communication flow path 20: Additive supply device 21: Pressure vessel 24: Thermal insulation chamber (box)
26 Temperature control device 27P Pressure sensor 30 Injection drive valve (injection opening/closing valve)
31 Injection check valve (injection on-off valve)
32 Downstream check valve 33 Downstream drive valve (connection flow passage shutoff valve)
35 Upstream drive valve (connection flow passage shutoff valve)
37: First flow path shutoff valve 40: Cylinder piston device 41A: First intake port (device connection part)
41B Second intake port (device connection part)
43 Outlet (device connection part)
50 Additive mixing device 60 Control unit 70 Mixing and discharging unit (third position)

Claims (14)

An additive mixing device that uses an additive supply device to introduce an additive into a communication flow path that connects a first position of a first flow path through which a first liquid flows and a second position downstream of the first position, and mixes the additive into the first liquid,
a flow switching device that switches between a first flow state in which the first liquid flows more into the first flow path than into the communication flow path from the first position and a second flow state in which the first liquid flows more into the communication flow path than into the first flow path from the first position;
a control unit that controls the additive supply device and the flow switching device so as to repeat a cycle of switching from the second flow state to the first flow state, introducing the additive into the communication flow path, and then returning to the second flow state ;
The flow switching device is
In the first flow state, the communication flow path can be switched between a first closed state in which the communication flow path is blocked from the first flow path so that the first liquid does not flow into an apparatus connection part to which the additive supply device is connected from both the first position and the second position, and a second closed state in which only discharge from the apparatus connection part to the second position is permitted,
The additive mixer blocks flow of the first fluid from the first location to the first flow path in the second flow condition . An additive mixing device that uses an additive supply device to introduce an additive into a communication flow path that connects a first position of a first flow path through which a first liquid flows and a second position downstream of the first position, and mixes the additive into the first liquid,
a flow switching device that switches between a first flow state in which the first liquid flows more into the first flow path than into the communication flow path from the first position and a second flow state in which the first liquid flows more into the communication flow path than into the first flow path from the first position;
a control unit that controls the additive supply device and the flow switching device so as to repeat a cycle of switching from the second flow state to the first flow state, introducing the additive into the communication flow path, and then returning to the second flow state;
The flow switching device is
In the first flow state, the communication flow path can be switched between a first closed state in which the communication flow path is blocked from the first flow path so that the first liquid does not flow into an apparatus connection part to which the additive supply device is connected from both the first position and the second position, and a second closed state in which only discharge from the apparatus connection part to the second position is permitted,
The additive mixer throttles the flow of the first liquid from the first position to the first flow path when switching from the first flow state to the second flow state . The additive is a liquid physical foaming agent, and is injected into the communication flow path by the additive supply device at a pressure that suppresses vaporization,
3. The additive mixing device according to claim 1, wherein the first liquid is caused to flow through the first flow passage and the communication flow passage at a pressure sufficient to suppress vaporization of the additive . a pressure vessel capable of storing the additive in a pressurized state in which evaporation of the additive is suppressed and supplying the additive to the communication flow path;
A temperature control device having one or both of a heater and a cooler for heating and cooling the pressure vessel;
a pressure sensor for detecting a pressure of the additive discharged from the pressure vessel;
4. The additive mixing device according to claim 3, further comprising: an output control unit that controls the output of the temperature adjusting device so that the pressure detected by the pressure sensor becomes a first pressure that is preset as a pressure that suppresses evaporation of the additive. 5. The additive mixing device according to claim 4, wherein the temperature adjusting device has a box that houses the pressure vessel and heats or cools the inside of the box . The additive mixing device according to any one of claims 1 to 5, wherein the flow switching device includes a communication flow path shutoff valve that shuts off the communication flow path from the first flow path in response to an abnormality in pressure drop in the first flow path or the communication flow path. The additive mixing device according to any one of claims 1 to 6, wherein the flow switching device is arranged in the communication flow path upstream of the device connection portion and includes an upstream valve that is driven to open and close in response to a command from the control portion. The additive mixing device according to any one of claims 1 to 7, wherein the flow switching device is arranged in the communication flow path downstream of the device connection portion and includes a downstream check valve that allows only flow from the communication flow path to the first flow path. The additive is a liquid physical foaming agent,
the additive supply device includes a pressure vessel that stores the additive at a first pressure that is preset as a pressure for suppressing vaporization of the additive, an injection on-off valve that is provided between the pressure vessel and the communication flow path, and a cylinder-piston device that draws in a fixed amount of liquid from the communication flow path and then discharges the liquid into the communication flow path,
the first liquid is caused to flow through the first flow path and the communication flow path at a pressure equal to or greater than the first pressure;
The additive mixing device according to any one of claims 1 to 8, wherein the control unit controls the additive supply device and the flow switching device so that, in the first flow state and the first closed state, the injection on-off valve is opened to cause the cylinder piston device to perform a suction operation, and then, in the first flow state and the second closed state, the injection on-off valve is closed to cause the cylinder piston device to perform a discharge operation, and then the additive mixing device is switched to the second flow state . The injection on-off valve is an injection drive valve that is driven to open and close in response to a command from the control unit,
10. The additive mixing device according to claim 9, wherein the control unit controls the injection drive valve to be in an open state only when the cylinder piston device is caused to perform a suction operation . the flow switching device is disposed in the communication flow path downstream of the device connection portion, and includes a downstream valve that is driven to open and close in response to a command from the control portion,
11. The additive mixing device according to claim 9, wherein the control unit controls the downstream drive valve to be in an open state only when the injection on-off valve is in a closed state . An additive mixing device according to any one of claims 1 to 11;
a second flow path connected to a third position downstream of the second position of the first flow path, through which a second liquid flows,
A foamed resin molded body manufacturing apparatus for producing a foamed resin molded body from the first liquid containing the additive and the second liquid. The foamed resin molded body manufacturing apparatus according to claim 12, wherein one of the first liquid and the second liquid is a first urethane stock solution containing a polyol as a main component, and the other is a second urethane stock solution containing a polyisocyanate as a main component, and a polyurethane foam is produced from the first liquid containing the additive and the second liquid . a first feed pump configured to feed the first liquid to the first flow path;
a second feed pump configured to feed the second liquid to the second flow path;
a discharge gun provided at an end of the first flow path and having a trigger for operating whether or not to discharge a mixed liquid of the first liquid and the second liquid,
the first feed pump and the second feed pump are activated or stopped due to operation of the trigger;
The foamed resin molded article manufacturing apparatus according to claim 12 or 13, wherein the control unit controls the additive supply device and the flow switching device to be linked to the first feed pump .

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