WO2021054148A1

WO2021054148A1 - Check valve, cassette having check valve, and method of manufacturing check valve

Info

Publication number: WO2021054148A1
Application number: PCT/JP2020/033596
Authority: WO
Inventors: Kaoru HOSOE; Masatsugu Igarashi
Original assignee: Terumo Kabushiki Kaisha
Priority date: 2019-09-18
Filing date: 2020-09-04
Publication date: 2021-03-25

Abstract

A check valve (10) includes a cover member (40) constituted by flexible cover member side resin sheets (42) and including an accommodation space (41), and a main body member (50) constituted by flexible main body member side resin sheets (54) and disposed in the accommodation space (41). The main body member (50) includes, on the inner side thereof, a communication space (51), and an opening/closing port member (52) capable of switching between a communicating state in which the communication space (51) and the accommodation space (41) are in communication, and a blocked state in which communication between the communication space (51) and the accommodation space (41) is blocked. The main body member (50) is directly or indirectly fixed to the cover member (40), whereas at least a side thereof at a location where the opening/closing port member (52) is formed is separated from the cover member (40).

Description

CHECK VALVE, CASSETTE HAVING CHECK VALVE, AND METHOD OF MANUFACTURING CHECK VALVE

The present invention relates to a check valve, a cassette having a check valve, and a method of manufacturing a check valve, in which the check valve allows flow of a fluid in one direction while blocking the fluid from flowing in a reverse direction to the one direction.

In the medical field, a fluid path is constructed by using a plurality of tubes and the like, and liquids containing biological components (blood, a cell fluid, etc.), medicinal solutions, and other substances are made to flow through the fluid path, whereby an appropriate treatment is performed. In such a fluid path, the flow direction of the fluid can be regulated by disposing a check valve therein.

As this type of check valve, for example, as disclosed in European Patent Application Publication No. 0168156, a check valve is used in which a valve is accommodated inside a housing. The valve is a duck bill valve made of an elastic resin material. On the other hand, the housing is made of a material that is harder than the valve, and the housing has an upstream flow path and a downstream flow path that are capable of communicating with the interior of the valve, and is formed in a shape that enables the valve to be firmly fixed therein.

Incidentally, in a check valve such as the one disclosed in European Patent Application Publication No. 0168156, manufacturing costs are high due to the need for molding the housing which has a rigid and complicated structure, and further, there is an inconvenience in that the check valve is easily damaged when it comes into contact with other members.

The present invention has been devised with the aim of solving the aforementioned problems, and has the object of providing a check valve, a cassette having such a check valve, and a method of manufacturing the check valve, which enable the check valve to be easily molded, and are capable of significantly reducing manufacturing costs.

In order to achieve the aforementioned object, a first aspect of the present invention is characterized by a check valve that allows flow of a fluid from a first end to a second end, while blocking the fluid from flowing from the second end to the first end, the check valve comprising a cover member constituted by a flexible resin sheet and including an accommodation space, and a main body member constituted by a flexible resin sheet and disposed in the accommodation space, wherein the main body member includes, on an inner side thereof, a communication space in which the fluid is capable of flowing, and an opening/closing port member communicating with the communication space and configured to be capable of switching between a communicating state in which the communication space and the accommodation space are in communication, and a blocked state in which communication between the communication space and the accommodation space is blocked, and the main body member is directly or indirectly fixed to the cover member on a side of the first end, whereas at least a side of the main body member at a location where the opening/closing port member is formed is separated from the cover member.

Further, in order to achieve the aforementioned object, a second aspect of the present invention is characterized by a sheet-shaped cassette including, in an interior thereof, a flow path for a fluid by joining together a pair of flexible resin sheets for the cassette, the cassette comprising, in a predetermined position in the flow path, a check valve configured to allow flow of the fluid from a first end to a second end, while blocking the fluid from flowing from the second end to the first end, and the check valve comprising a cover member constituted by the resin sheets for the cassette and including an accommodation space, and a main body member constituted by a flexible main body member side resin sheet and disposed in the accommodation space, wherein the main body member includes, on an inner side thereof, a communication space in which the fluid is capable of flowing, and an opening/closing port member communicating with the communication space and configured to be capable of switching between a communicating state in which the communication space and the accommodation space are in communication, and a blocked state in which communication between the communication space and the accommodation space is blocked, and the main body member is directly or indirectly fixed to the cover member on a side of the first end, whereas at least a side of the main body member at a location where the opening/closing port member is formed is separated from the cover member.

Furthermore, in order to achieve the aforementioned object, a third aspect of the present invention is characterized by a method of manufacturing a check valve that allows flow of a fluid from a first end to a second end, while blocking the fluid from flowing from the second end to the first end, the check valve comprising a cover member constituted by a flexible cover member side resin sheet and including an accommodation space, and a main body member constituted by a flexible main body member side resin sheet and disposed in the accommodation space, wherein the main body member includes, on an inner side thereof, a communication space in which the fluid is capable of flowing, and an opening/closing port member communicating with the communication space and configured to be capable of switching between a communicating state in which the communication space and the accommodation space are in communication, and a blocked state in which communication between the communication space and the accommodation space is blocked, and the main body member is directly or indirectly fixed to the cover member on a side of the first end, whereas at least a side of the main body member at a location where the opening/closing port member is formed is separated from the cover member, the method comprising a first manufacturing step of manufacturing the main body member from a base material that constitutes the main body member side resin sheet, and a second manufacturing step of manufacturing the cover member, in a state in which the main body member manufactured by the first manufacturing step is placed on a base material that constitutes the cover member side resin sheet.

The above-described check valve, the cassette having such a check valve, and the method of manufacturing the check valve enable the check valve to be easily molded, and are capable of significantly reducing manufacturing costs.

FIG. 1 is a perspective view of a check valve according to a first embodiment of the present invention; FIG. 2A is an explanatory diagram showing an example of a fluid path to which the check valve of FIG. 1 is applied;FIG. 2B is an explanatory diagram showing another example of a fluid path to which the check valve of FIG. 1 is applied; FIG. 3A is a plan view of the check valve shown in FIG. 1;FIG. 3B is a plan view of a check valve having another main body member; FIG. 4 is a side cross-sectional view of the check valve shown in FIG. 1; FIG. 5A is a first explanatory diagram showing a process of a main body member manufacturing step;FIG. 5B is a second explanatory diagram showing the process of the main body member manufacturing step;FIG. 5C is a third explanatory diagram showing the process of the main body member manufacturing step; FIG. 6A is a first explanatory diagram showing a process of a cover member manufacturing step;FIG. 6B is a second explanatory diagram showing the process of the cover member manufacturing step;FIG. 6C is a third explanatory diagram showing the process of the cover member manufacturing step;FIG. 6D is a fourth explanatory diagram showing the process of the cover member manufacturing step; FIG. 7A is a side cross-sectional view showing a forward flow of a fluid at a time when the check valve is used;FIG. 7B is a side cross-sectional view showing a flow of a fluid in a reverse direction at a time when the check valve is used; FIG. 8 is a perspective view showing a cassette having a check valve according to a second embodiment of the present invention; FIG. 9A is a first explanatory diagram showing a process of a cover member manufacturing step of manufacturing the cassette shown in FIG. 8; andFIG. 9B is a second explanatory diagram showing the process of the cover member manufacturing step of manufacturing the cassette shown in FIG. 8.

Preferred embodiments of the present invention will be presented and described in detail below with reference to the accompanying drawings.

(First Embodiment)
As shown in FIG. 1, a check valve 10 according to a first embodiment of the present invention is connected to a medical device such as tubes 12 or the like for medical use, and serves to regulate a flow direction of a fluid (a liquid or a gas) during a medical treatment. More specifically, the check valve 10 includes a space for the fluid in the interior thereof, and allows the fluid to flow in one direction (hereinafter, referred to as a forward direction), while blocking the fluid from flowing in a reverse direction to the forward direction. In particular, the check valve 10 according to the present embodiment is manufactured in a sheet-like shape having a predetermined thickness by using flexible resin sheets. More specifically, the check valve 10 is configured so as to have flexibility as a whole, and by being appropriately deformed, for example, when another member is placed in contact with the check valve 10, is capable of releasing a contact pressure.

As shown in FIGS. 2A and 2B, the check valve 10 is provided at an appropriate position in a fluid path 14 through which the fluid flows at the time of a medical treatment. The fluid path 14 is made up from a plurality of tubes 12 and a branch connector 16 or the like, and supplies a fluid of a medicinal solution or blood from one medical bag 18 to a patient (or another medical bag 18, or a treatment unit that performs a treatment on the fluid, or the like). More specifically, a fluid path 14A shown in FIG. 2A includes a first path 20, a second path 22, and a third path 24 which are connected to each other via the branch connector 16, and the check valve 10 is installed midway along the first path 20, and further, a filter member 26 is installed midway along the second path 22. The filter member 26 removes foreign matter or a specific substance (component) in the fluid that flows through the second path 22.

In this case, the fluid path 14 allows a medicinal solution (first fluid) in the medical bag 18 to flow through the first path 20, the branch connector 16, and the third path 24, and further, a medicinal solution (second solution) different from the medicinal solution in the medical bag 18 is allowed to flow through the second path 22, the branch connector 16, and the third path 24. The check valve 10 provided in the first path 20, while allowing the medicinal solution to flow out from the medical bag 18, regulates the intrusion of another medicinal solution, air, or the like into the medical bag 18. Moreover, various liquids and gases may be applied to the first and second fluids.

The check valve 10 provided in the first path 20 has a first end 30 which is one end in the longitudinal direction and to which a first tube 12a (first medical device) is connected, and a second end 34 which is another end in the longitudinal direction and to which a second tube 12b (second medical device) is connected. Moreover, the check valve 10 is not limited to a configuration serving as a relay between the two tubes 12, and for example, the first end 30 may be directly connected to a port of the medical bag 18, or alternatively, the second end 34 may be directly connected to the branch connector 16.

Further, as shown in FIG. 2B, in a medical bag system (fluid path 14B) including a plurality of medical bags 18 and a plurality of tubes 12 connecting the respective medical bags 18, the check valve 10 may be connected to a vent member 28 that removes air from inside the fluid path 14B. The vent member 28 includes a filter 28a in the interior thereof that allows permeation of gas while blocking permeation of liquid, and the check valve 10 is attached to an air outlet side of the vent member 28. Consequently, the check valve 10 allows outflowing of air from the fluid path 14B, while preventing air from entering the fluid path 14B.

In essence, the medical device to which the check valve 10 is applied is not particularly limited, and the check valve 10 can be satisfactorily applied to a case in which it is desired to regulate the flow of a fluid in one direction in the fluid path 14, and a case in which it is desired to block the flow of a fluid from another direction in the fluid path 14.

As shown in FIGS. 1, 3A, and 4, the check valve 10 is formed in a substantially rectangular shape as viewed in plan, and is formed in a shape in which portions thereof on inner sides of respective lateral sides of the rectangular shape bulge in the thickness direction. The check valve 10 is equipped with a cover member 40 having an accommodation space 41, and a main body member 50 disposed in the accommodation space 41, and the cover member 40 makes up the main external appearance of the check valve 10.

A first connector 32 for connection to a first medical device is attached to the first end 30 of the check valve 10. A second connector 36 for connection to a second medical device is attached to the second end 34 of the check valve 10. In the present embodiment, for the first and

second connectors

32 and 36 of the check valve 10, cylindrical bodies, which include

hollow parts

32a and 36a at axial centers thereof and in which the outer surfaces of exposed portions are formed in a tapered shape, are applied. However, the present invention is not limited to this feature, and the first and

second connectors

32 and 36 may be formed in an appropriate shape in accordance with the medical devices to which they are attached. For example, the first and

second connectors

32 and 36 may be formed in a male screw shape or a female screw shape, or may have female screw portions for locking provided on outer side tubes of the cylindrical bodies. For the first and

second connectors

32 and 36, there may be adopted connectors having the same shape as each other, or there may be adopted connectors having shapes that differ from each other.

As viewed in plan, the cover member 40 of the check valve 10 includes the accommodation space 41 having a rectangular shape. The check valve 10 is of a form in which the main body member 50 is fixed to the first end 30 side of the cover member 40, whereas the main body member 50 is separated from the second end 34 side of the cover member 40. By forming the accommodation space 41 having a certain volume on the outer side of the main body member 50, the cover member 40 is capable of temporarily storing the fluid, and further, when the fluid flows into the accommodation space 41 from the second end 34, the internal pressure on the outer side of the main body member 50 is increased, thereby preventing the fluid from flowing in reverse to the main body member 50.

Further, as shown in FIGS. 3A and 4, the cover member 40 is configured by joining together a pair of flexible cover member side resin sheets 42. Therefore, the cover member 40 includes a cover member side joined portion 44 formed by joining (sealing) together the pair of cover member side resin sheets 42 so as to surround the periphery of the accommodation space 41. More specifically, the cover member side joined portion 44 includes a cover member first end side 44a constituting the first end 30, a cover member second end side 44b constituting the second end 34, and both sides in the widthwise direction (a pair of cover member lateral sides 44c) of the cover member 40. In addition, the cover member first end side 44a is joined to a main body member first end side 56a, to be described later, which is formed on the main body member 50.

A resin material that is softer than the first and

second connectors

32 and 36 may be applied to the pair of cover member side resin sheets 42. As the material of the cover member side resin sheets 42, for example, there may be cited a material containing at least one selected from among polyvinyl chloride resin, polyurethane resin, and ethylene-vinyl acetate copolymer resin (EVA) as a primary component. In the case that such materials are applied, high frequency welding using a high frequency can be adopted as a joining means for joining the pair of cover member side resin sheets 42, and molding of the main body member 50 by the pair of cover member side resin sheets 42 can be facilitated.

The first connector 32 is joined (sealed) to a central portion in the widthwise direction of the cover member first end side 44a, whereas the second connector 36 is joined (sealed) to a central portion in the widthwise direction of the cover member second end side 44b. The means for fixing the pair of cover member side resin sheets 42 to the first and

second connectors

32 and 36 is not particularly limited, and in addition to the aforementioned high frequency welding, adhesion, other type of welding or the like can be applied.

Further, the shape of the cover member 40 is not limited to being a rectangular shape as viewed in plan, and various shapes may be adopted. For example, the cover member 40 may be formed in a circular shape (a perfect circular shape, an elliptical shape), or may be formed in another polygonal shape as viewed in plan. Further, the cover member 40 may exhibit a more three-dimensional shape (a cylindrical shape, a conical shape, a spherical shape, a box-like shape, a rod shape, or the like) by being formed so as to have a large bulge between the resin sheets. Conversely, the cover member 40 may be formed in a flat shape without having a bulge therein. The shape of the main body member 50 may also adopt an appropriate shape depending on the shape of the cover member 40.

As shown in FIGS. 1, 3A, and 4, the main body member 50 of the check valve 10 includes, on the inner side thereof, a communication space 51 in which the fluid is capable of flowing, and further includes an opening/closing port member 52 that communicates with the communication space 51 and is capable of switching between a communicating state in which the communication space 51 and the accommodation space 41 are in communication, and a blocked state in which communication between the communication space 51 and the accommodation space 41 is blocked. Consequently, the main body member 50 plays a role in actually carrying out switching between flowing of the fluid and blocking the flow of the fluid in the check valve 10. The main body member 50 is configured by joining together a pair of flexible main body member side resin sheets 54.

More specifically, the main body member 50 extends longitudinally in a direction from the first end 30 to the second end 34 of the check valve 10, and the communication space 51 is formed between the pair of main body member side resin sheets 54 along the direction of extension. The communication space 51 communicates with the hollow part 32a of the first connector 32, and communicates with the opening/closing port member 52 on an opposite side therefrom (in proximity to the second end 34 of the check valve 10).

The material that constitutes the pair of main body member side resin sheets 54 is not particularly limited, and can be appropriately selected from among the materials mentioned for the cover member side resin sheets 42. For the cover member side resin sheets 42 and the main body member side resin sheets 54, the same resin material may be applied thereto in order to enhance the joining ability between both members, or different resin materials may be applied thereto if a change in the physical properties thereof is given precedence.

The main body member 50 according to the present embodiment is formed in a rectangular shape as viewed in plan. A hollow cylindrical body 33a, which serves as a member of the first connector 32, is joined to the main body member 50 on the side of the first end 30. More specifically, the first connector 32 of the check valve 10 is constituted by two members, namely, the cylindrical body 33a, and a connector main body 33b having the above-described outer shape for connection to the medical device, and the two members each include the hollow part 32a of the same cross-sectional shape on the central axis thereof. The cylindrical body 33a and the connector main body 33b are fixed together in series in an aligned fashion at the time of manufacturing, whereby the hollow part 32a is made continuous. It should be noted that the second connector 36 is constituted by one individual member.

On the first end 30 side of the main body member 50, the main body member first end side 56a is formed having a portion that makes up a joining port member 55 that is joined to the cylindrical body 33a, and a portion where the pair of main body member side resin sheets 54 are joined to each other on the side of the joining port member 55. The pair of main body member side resin sheets 54 are not joined to each other at a location in proximity to the second end 34 in the main body member 50, whereby the opening/closing port member 52 is formed. The pair of main body member side resin sheets 54 are joined to each other on both sides in the lateral direction (widthwise direction) perpendicular to the longitudinal direction (direction of extension) of the main body member 50, whereby a pair of main body member lateral sides 56b are formed. The main body member first end side 56a and the main body member lateral sides 56b make up a main body member side joined portion 56.

Further, at the time of manufacturing, the pair of main body member side resin sheets 54 are shaped so as to be in close proximity to each other from the joining port member 55 (the first end 30) toward the opening/closing port member 52. In greater detail, in a side cross-sectional view taken along a thickness direction of the main body member 50 shown in FIG. 4, the main body member 50 includes a first extending portion 58, a transitioning portion 60, and a second extending portion 62, provided sequentially in this order from the main body member first end side 56a toward the second end 34. In the first extending portion 58, the pair of main body member side resin sheets 54 extend mutually in parallel to each other from the first end 30 toward the second end 34 at an interval corresponding substantially to the diameter of the cylindrical body 33a. In the second extending portion 62, the pair of main body member side resin sheets 54 are in contact with each other and extend mutually in parallel in a state in which the fluid is not flowing. Also in a state where the fluid is flowing, the pair of main body member side resin sheets 54 in the second extending portion 62 extend in parallel on a more inward side than the pair of main body member side resin sheets 54 in the first extending portion 58.

As shown in FIGS. 3A and 4, the dimension L1 of the first extending portion 58 along the longitudinal direction (direction of extension) of the main body member 50 is longer than the dimension L2 of the second extending portion 62 along the longitudinal direction. The dimension L1 of the first extending portion 58 is not particularly limited, but may be set within a range of from 7 mm to 30 mm, for example. Similarly, the dimension L2 of the second extending portion 62 is not particularly limited, but may be set within a range of from 2 mm to 15 mm, for example.

Further, in the second extending portion 62, the inner surfaces that constitute the communication space 51 (opposing surfaces of the pair of main body member side resin sheets 54) are formed into smooth surfaces 62a having no fine unevenness. Consequently, in a state in which the fluid is not flowing, it is made easier for the inner surfaces of the second extending portion 62 to adhere to each other, and it becomes easier to maintain the closed state of the opening/closing port member 52. Moreover, in the case that the pair of main body member side resin sheets 54 are made of a material that is easy to adhere, they may have fine unevenness without being formed into smooth surfaces 62a, or conversely, a hydrophilic coating or the like may be applied thereto. Further, the inner surfaces of the first extending portion 58 and the transitioning portion 60 may be formed into smooth surfaces 62a or may be provided with fine unevenness.

Meanwhile, the transitioning portion 60 has an arcuate shape (rounded shape) at each of the locations where the transitioning portion 60 is respectively connected to the first extending portion 58 and the second extending portion 62, and further, the transitioning portion 60 is inclined in a direction in which the main body member side resin sheets 54 mutually approach toward the second extending portion 62. Stated otherwise, the transitioning portion 60 causes the inner surfaces constituting the communication space 51 to smoothly change. The dimension of the transitioning portion 60 along the longitudinal direction of the main body member 50 is shorter than the dimensions of the first extending portion 58 and the second extending portion 62.

Further, as shown in FIG. 3B, a main body member 50A may be formed in a shape in which the width W2 of the second extending portion 62 is shorter than the width W1 of the first extending portion 58 as viewed in plan. More specifically, in the main body member 50A, the pair of main body member lateral sides 56b in the first extending portion 58 extend in parallel to each other from the first end 30. In addition, the pair of main body member lateral sides 56b in the transitioning portion 60 are inclined so that the interval therebetween gradually decreases from the first extending portion 58 toward the second extending portion 62. Further, the pair of main body member lateral sides 56b in the second extending portion 62 extend in parallel to each other with an interval shorter than that in the first extending portion 58.

It is preferable that the dimension L1 in the direction of extension of the first extending portion 58 and the width W1, as well as the dimension L2 in the direction of extension of the second extending portion 62 and the width W2 be appropriately determined based on, for example, the material of the pair of main body member side resin sheets 54. For example, if the material of the main body member side resin sheets 54 is such that they are weakly adhered to each other, it is possible to make it more difficult for the fluid to leak by lengthening the dimension L2 of the second extending portion 62 and shortening the width W2. On the other hand, if the material of the main body member side resin sheets 54 is such that they are strongly adhered to each other, the fluid can be made to flow more easily by shortening the dimension L2 of the second extending portion 62 and lengthening the width W2. In particular, depending on the material of the main body member side resin sheets 54, the main body member 50A may be constituted by the first extending portion 58 and the transitioning portion 60, with the dimension L2 set to zero (by eliminating the second extending portion 62).

In this instance, a case will be exemplified in which ethylene-vinyl acetate copolymer resin (EVA) is applied as the material of the main body member side resin sheets 54, and the

main body members

50 and 50A are manufactured. In this case, in the main body member side resin sheets 54, the surface roughness on the side of the inner surfaces that make up the communication space 51 can be set to less than or equal to 0.10 micrometers. Further, in the case that the thickness of the pair of main body member side resin sheets 54 is 0.37 mm, the dimension L1 of the first extending portion 58 may be set to 22.6 mm, the width W1 may be set to 15 mm, the dimension L2 of the second extending portion 62 may be set to 0 mm (in other words, the second extending portion 62 is eliminated), and the width W2 at the distal end of the transitioning portion 60 may be set to 7.0 mm.

As shown in FIGS. 1, 3A, and 4, in the check valve 10, the interval between the pair of main body member lateral sides 56b of the main body member 50 is smaller than the interval between the pair of cover member lateral sides 44c. Therefore, a gap 46 (a portion of the accommodation space 41) exists between the cover member 40 and the sides (side periphery) of the main body member 50, and liquid is capable of flowing into the gap 46.

Accordingly, the main body member 50 is separated from the cover member 40 at least on the side of the location where the opening/closing port member 52 is formed. Owing to this feature, when the fluid flows from the second connector 36 (the second end 34) into the accommodation space 41, by the fluid moving into the gap 46 (the sides in the vicinity of the opening/closing port member 52), opening of the opening/closing port member 52 is inhibited, and it is possible to prevent the fluid from entering the communication space 51.

Next, a method of manufacturing the above-described check valve 10 will be described in detail with reference to FIGS. 5A to 6D.

In the method of manufacturing the check valve 10, a main body member manufacturing step (first manufacturing step) for manufacturing the main body member 50 that forms the inner side portion of the check valve 10 is executed, and next, a cover member manufacturing step (second manufacturing step) for manufacturing the cover member 40 while accommodating the main body member 50 therein is executed.

In the main body member manufacturing step, as shown in FIG. 5A, initially, two main body member base material sheets 64 that make up the main body member side resin sheets 54, and the cylindrical body 33a are prepared, and a main body member positioning step of positioning the respective members is carried out. More specifically, one of the two main body member base material sheets 64 is laid on a first mold of a non-illustrated main body member manufacturing device, the cylindrical body 33a is arranged at a predetermined position on the main body member base material sheet 64, and in a state in which the cylindrical body 33a is arranged thereon, the other one of the main body member base material sheets 64 is covered thereon.

Next, as shown in FIG. 5B, a main body member sealing step of sealing the two main body member base material sheets 64 and the cylindrical body 33a is performed by the main body member manufacturing device. At this time, the main body member manufacturing device presses a second mold from an opposite side of the main body member base material sheets 64 that are arranged in the first mold, and high frequency welding is carried out between the first mold and the second mold. The first and second molds include a cavity (a shape corresponding to the first extending portion 58, the transitioning portion 60, and the second extending portion 62) for the communication space 51 that is intended to be formed. In the main body member manufacturing device, while high frequency welding is carried out around the periphery of the cavity (the cylindrical body 33a, the main body member first end side 56a, and the main body member lateral sides 56b), air is introduced between the two main body member base material sheets 64 that are positioned in the cavity. Consequently, the two main body member base material sheets 64 and the cylindrical body 33a are sealed in a manner so as to include the communication space 51 of a predetermined shape.

Finally, as shown in FIG. 5C, on the main body member base material sheets 64 after having been subjected to sealing, a main body member cutting step of forming the main body member 50 is performed by cutting (trimming) the periphery around the communication space 51. For example, the main body manufacturing device cuts the main body member base material sheets 64 by advancing a cutter matching the shape of the main body member 50 in the main body member base material sheets 64 that have been sealed and are arranged on the first mold after completion of high frequency welding. Consequently, in the main body member manufacturing step, the main body member 50 in which the pair of main body member side resin sheets 54 are sealed and the cylindrical body 33a is joined thereto is suitably manufactured.

In addition, in the cover member manufacturing step, as shown in FIG. 6A, initially, using the main body member 50 that was manufactured in the above-described main body member manufacturing step, and two cover member base material sheets 48 that make up the cover member side resin sheets 42, a cover member positioning step of positioning the respective members is carried out. More specifically, one of the two cover member base material sheets 48 is laid on a first mold of a non-illustrated cover member manufacturing device, the main body member 50 is arranged at a predetermined position on the cover member base material sheet 48, and in a state in which the main body member 50 is arranged thereon, the other one of the cover member base material sheets 48 is covered thereon.

Next, as shown in FIG. 6B, a cover member sealing step of sealing the two cover member base material sheets 48 and the main body member 50 is performed by the cover member manufacturing device. In this case as well, the cover member manufacturing device presses a second mold from an opposite side of the cover member base material sheets 48 that are arranged in the first mold, and high frequency welding is carried out between the first mold and the second mold. The first and second molds of the cover member manufacturing device include a cavity corresponding to the accommodation space 41 of the cover member 40 that is intended to be formed. In a state in which the main body member 50 is positioned in the cavity, in the cover member manufacturing device, while high frequency welding is carried out around the periphery (the cover member first end side 44a, the cover member second end side 44b, and the cover member lateral sides 44c) thereof, air is introduced between the two cover member base material sheets 48 that are positioned in the cavity. Consequently, the two cover member base material sheets 48 and the main body member 50 are sealed in a manner so as to include the accommodation space 41. Moreover, during the high frequency welding, air need not necessarily be introduced between the two cover member base material sheets 48. In the cover member sealing step, a state is established in which sealing is not carried out on locations corresponding to the connector main body 33b and the second connector 36, but the periphery around such members is sealed.

Next, as shown in FIG. 6C, a cover member cutting step of forming the cover member 40 is performed by cutting (trimming) the periphery around the sealed accommodation space 41. Consequently, the pair of cover member side resin sheets 42, which include the main body member 50 in the interior of the accommodation space 41, are formed.

Furthermore, in the cover member manufacturing step, as shown in FIG. 6D, a connector joining step is carried out for joining the connector main body 33b of the first connector 32 and the second connector 36 to the pair of cover member side resin sheets 42 that were formed in the cover member cutting step. More specifically, as described above, the pair of cover member side resin sheets 42 are not sealed at locations corresponding to the connectors, and in the connector joining step, the connector main body 33b and the second connector 36 are inserted respectively into such non-sealed portions, and the portions in which the members were inserted are sealed. Consequently, the check valve 10 shown in FIG. 3A is suitably manufactured.

The check valve 10 according to the present embodiment is basically configured in the manner described above. Next, a description will be given below concerning operations thereof.

The check valve 10 is used when a medical staff person such as a doctor or the like constructs the fluid path 14. For example, as shown in FIG. 2A, the check valve 10 is arranged between the first tube 12a and the second tube 12b of the fluid path 14A (the first path 20). Since the check valve 10 is configured in the shape of a flexible sheet, the check valve 10 can be easily deformed even if it comes into contact with another member at the time that the fluid path 14 is constructed or used. Accordingly, damage or the like to the check valve 10 is suppressed.

Further, as shown in FIG. 7A, when the fluid flows therein from the first tube 12a, the check valve 10 allows the fluid to smoothly flow in the forward direction, and to flow out into the second tube 12b. More specifically, the fluid, which has flowed into the check valve 10 from the first tube 12a, flows into the communication space 51 of the main body member 50 through the hollow part 32a of the first connector 32. The fluid flows stably in the longitudinal direction in the first extending portion 58 in which the pair of main body member side resin sheets 54 extend in parallel. At the transitioning portion 60 of the main body member 50, the pair of main body member side resin sheets 54 approach inwardly in a smooth fashion, and the pair of main body member side resin sheets 54 in the second extending portion 62 disposed on the side in the forward direction are made to separate on the basis of the fluid flow pressure. Consequently, the opening/closing port member 52 of the second extending portion 62 smoothly opens. Therefore, the fluid flows smoothly through the communication space 51, and flows out from the opening/closing port member 52.

The fluid that has flowed out of the opening/closing port member 52 into the accommodation space 41 of the cover member 40 temporarily passes through the accommodation space 41 and flows toward the second end 34. The fluid flows into the hollow part 36a of the second connector 36 that protrudes into the accommodation space 41, and flows out into the second tube 12b of the check valve 10 via the hollow part 36a.

On the other hand, as shown in FIG. 7B, when the fluid flows therein from the second tube 12b, the check valve 10 blocks the flow of the fluid in the reverse direction. More specifically, the fluid, which has flowed into the check valve 10 from the second tube 12b, flows into the accommodation space 41 of the cover member 40 through the hollow part 36a of the second connector 36. By the fluid flowing into the gap 46 on the outer side of the main body member 50, the fluid presses the outer surfaces of the main body member 50 inwardly (in a direction in which the pair of main body member side resin sheets 54 come into contact with each other). Consequently, the opening/closing port member 52 of the main body member 50 is satisfactorily closed. As a result, the fluid, which has flowed into the check valve 10 from the second tube 12b, does not flow into the communication space 51 of the main body member 50, and is prevented from flowing in a reverse direction.

Moreover, it should be noted that the present invention is not limited to the above-described embodiment, and various modifications can be adopted in accordance with the essence and gist of the present invention. For example, the main body member 50 is not limited to being molded by joining together the pair of (two) main body member side resin sheets 54, and may be molded by a single main body member side resin sheet 54, or may be molded by three or more of the main body member side resin sheets 54. Similarly, the cover member 40 is not limited to being molded by joining together the pair of cover member side resin sheets 42, and may be molded by a single cover member side resin sheet 42, or may be molded by three or more of the cover member side resin sheets 42.

Further, the check valve 10 may be configured without being equipped with the first connector 32 and the second connector 36. Furthermore, in the present embodiment, the first connector 32 is constituted by two members (the cylindrical body 33a and the connector main body 33b), however, the first connector 32 is not limited to this feature, and may be constituted by one individual member.

Still further, the check valve 10 according to the present embodiment is of a configuration in which the first end 30 side of the main body member 50 (the main body member first end side 56a) is directly joined and fixed to the cover member 40 (the cover member first end side 44a). However, the check valve 10 may be configured in a manner so that the main body member 50 is indirectly fixed to the cover member 40. For example, the main body member 50 may be joined to the first connector 32, and the cover member 40 is also joined to the first connector 32, whereby a configuration can be provided in which the main body member 50 and the cover member 40 are not directly joined to (in contact with) each other.

(Second Embodiment)
A check valve 10A according to a second embodiment of the present invention will be described below with reference to Fig. 8. In the following description, constituent elements having the same configuration or the same function as those of the above-described embodiment will be designated by the same reference numerals, and detailed description of such features will be omitted.

The check valve 10A according to the second embodiment differs from the check valve 10 according to the first embodiment, in that, in a sheet-shaped cassette 70 having a fluid flow path 72 in the interior thereof, the check valve 10A is disposed at an intermediate position of the flow path 72. More specifically, the check valve 10A is provided in the cassette 70 in order to regulate flow of the fluid in one direction (a forward direction), and to block the fluid from flowing in the reverse direction.

For example, the sheet-shaped cassette 70 is provided for the purpose of aggregating together a plurality of paths in a biological component kit 74 which is capable of transferring a liquid in which a biological component is contained. The biological component kit 74 is set in a non-illustrated biological component treatment device, and the liquid inside the biological component kit 74 is subjected to a treatment under operation of the biological component treatment device. Hereinafter, a configuration in which the biological component kit 74 and the biological component treatment device are included is referred to as a biological component treatment system 76.

In the present embodiment, the biological component treatment system 76 is constituted as a cell proliferation system in which, by a biological component treatment device (cell proliferation device), a liquid such as a liquid (cell fluid) containing cells of a living body, a culture medium, and a cleaning solution, etc., is caused to flow inside the biological component kit 74 (cell proliferation kit), a bioreactor (treatment unit) is seeded with the cells, and the culture medium is supplied thereto, whereby the cells are proliferated. Moreover, the biological component treatment system 76 (the biological component kit 74) to which the cassette 70 is applied is not limited to being used for proliferation of cells, and can be applied to a system in which various types of biological components (blood, a lymph fluid, etc.) are treated.

The cassette 70 is formed so as to exhibit a sheet-like shape as a whole, by using a pair of flexible resin sheets 78 for the cassette, and joining them together so as to include the flow path 72 of a predetermined shape therebetween. The flow path 72 of the cassette 70 is configured in a manner so as to have a predetermined flow path cross-sectional area, by the pair of resin sheets 78 for the cassette bulging in hemispherical shapes in opposite directions. In addition to the flow path 72 and the check valve 10A, as a configuration for communicating with the flow path 72, the cassette 70 includes a pressure detection unit 80 which is capable of detecting pressure, a liquid level detection unit 82 which is capable of detecting a liquid level, and a flow path opening/closing unit 84 which is capable of opening and closing the flow path 72, etc.

In the cassette 70, the check valve 10A is disposed between the flow path 72 (a first flow path 72a) that communicates with the liquid level detection unit 82, and the flow path 72 (a second flow path 72b) that is joined to a flow path for discharging the fluid. The check valve 10A enables air to be discharged from the liquid level detection unit 82, and blocks the inflow of the fluid from the second flow path 72b into the liquid level detection unit 82.

The check valve 10A includes the cover member 40 which is formed of the pair of resin sheets 78 for the cassette (in other words, the resin sheets 78 for the cassette serve as the cover member side resin sheets 42), and is configured so as to be equipped with the main body member 50 on the inner side of the cover member 40. The configuration of the main body member 50 of the check valve 10A is the same as that of the above-described check valve 10. Consequently, without being equipped with the first and

second connectors

32 and 36 in the interior of the cassette 70, the check valve 10A includes the first end 30 which is connected to the first flow path 72a, and the second end 34 which is connected to the second flow path 72b. In addition, the communication space 51 of the main body member 50 communicates with the first flow path 72a, and the accommodation space 41 of the cover member 40 communicates with the second flow path 72b. Moreover, the cylindrical body 33a is joined to the first end 30 side of the main body member 50 (the pair of main body member side resin sheets 54) according to the present embodiment, and the first flow path 72a and the second flow path 72b communicate with each other via the hollow part 32a of the cylindrical body 33a. The cylindrical body 33a may be omitted, as long as it is possible to maintain the open state of the main body member 50 on the side of the first end 30.

In the case that the check valve 10A described above is molded in the cassette 70, the manufacturing method therefor involves executing the main body member manufacturing step shown in FIGS. 5A to 5C to manufacture the main body member 50, and then executing the cover member manufacturing step as shown in FIGS. 9A and 9B, in the same manner as the above-described check valve 10. In the cover member manufacturing step, initially, a cover member positioning step of positioning the main body member 50 and the resin sheets 78 for the cassette is performed. More specifically, one of the two resin sheets 78 for the cassette is laid on a first mold of a non-illustrated cassette manufacturing device, the main body member 50 is arranged at a predetermined position on the resin sheet 78 for the cassette, and in a state in which the main body member 50 is arranged thereon, the other one of the resin sheets 78 for the cassette is covered thereon.

Next, a cover member sealing step of sealing the two resin sheets 78 for the cassette and the main body member 50 is performed by the cassette manufacturing device. The cassette manufacturing device presses a second mold from an opposite side of the resin sheets 78 for the cassette that are arranged in the first mold, and high frequency welding is carried out between the first mold and the second mold. The first and second molds of the cassette manufacturing device include a cavity corresponding to the flow path 72 (including the accommodation space 41 of the check valve 10A) that is intended to be formed. In a state in which the main body member 50 is positioned, in the cassette manufacturing device, while high frequency welding is carried out around the periphery of the flow path 72 that is intended to be formed, air is introduced between the two resin sheets 78 for the cassette that are positioned in the cavity. Consequently, the two resin sheets 78 for the cassette are sealed to thereby form the cassette 70 having the flow path 72.

At this time, on the first end 30 side of the check valve 10A, the resin sheets 78 for the cassette and the main body member side resin sheets 54 (the main body member first end side 56a) are joined together in a state in which the cylindrical body 33a places the first flow path 72a and the communication space 51 in communication with each other. On the second end 34 side of the check valve 10A, by the pair of resin sheets 78 for the cassette being joined at a position separated from the main body member 50, a state is brought about in which the accommodation space 41 and the second flow path 72b are placed in communication.

In the foregoing manner, the check valve 10A can be easily disposed in the sheet-shaped cassette 70. In addition, in the flow path 72 inside the sheet-shaped cassette 70, the check valve 10A allows the fluid to flow in the forward direction (from the first flow path 72a to the second flow path 72b), while blocking the fluid from flowing in the reverse direction (from the second flow path 72b to the first flow path 72a).

Even in the case that the check valve 10A is provided in the cassette 70, various configurations can be adopted. For example, according to the present embodiment, although a configuration is provided in which the cylindrical body 33a is provided only at a boundary between the check valve 10A and the first flow path 72a, a configuration may also be provided in which the same cylindrical body 33a is provided in the check valve 10A and the second flow path 72b.

Technical concepts and effects that can be grasped from the above-described embodiments will be described below.

The first aspect of the present invention is characterized by the check valve 10 or 10A that allows flow of the fluid from the first end 30 to the second end 34, while blocking the fluid from flowing from the second end 34 to the first end 30, the check valve 10 or 10A comprising the cover member 40 constituted by the flexible resin sheets (the cover member side resin sheets 42) and including the accommodation space 41, and the main body member 50 constituted by the flexible resin sheets (the main body member side resin sheets 54) and disposed in the accommodation space 41, wherein the main body member 50 includes, on the inner side thereof, the communication space 51 in which the fluid is capable of flowing, and the opening/closing port member 52 that communicates with the communication space 51 and is capable of switching between a communicating state in which the communication space 51 and the accommodation space 41 are in communication, and a blocked state in which communication between the communication space 51 and the accommodation space 41 is blocked, and the main body member 50 is directly or indirectly fixed to the cover member 40 on the side of the first end 30, whereas at least a side of the main body member 50 at a location where the opening/closing port member 52 is formed is separated from the cover member 40.

By including the cover member 40, which is constituted by the cover member side resin sheets 42, and the main body member 50, which is constituted by the main body member side resin sheets 54, the

check valve

10 or 10A which is configured in the above-described manner can be easily molded, and further, manufacturing costs can be significantly reduced. In particular, since the

check valve

10 or 10A has flexibility, it can be easily deformed even when another member is placed in contact therewith, and is capable of releasing the contact pressure and suppressing damage. In addition, in the

check valve

10 or 10A, since the side of the location where the main body member 50 is formed is separated from the cover member 40, the fluid that has flowed into the accommodation space 41 presses the main body member 50 to thereby suitably block the opening/closing port member 52, and even a slight amount of leakage of the fluid is capable of being suppressed.

Further, the main body member 50 is made up from the pair of resin sheets (the main body member side resin sheets 54), and both lateral sides thereof are joined from the first end 30 to the opening/closing port member 52. In accordance with this feature, at a time of manufacturing of the

check valve

10 or 10A, by joining both lateral sides of the pair of main body member side resin sheets 54, the main body member 50 having the communication space 51 and the opening/closing port member 52 can be easily molded.

Further, in a side cross-sectional view taken along a thickness direction of the main body member 50, the main body member 50 includes the first extending portion 58 provided on the side of the first end 30, and the second extending portion 62 provided on the side of the second end 34, and the pair of resin sheets (the main body member side resin sheets 54) positioned on the second extending portion 62 extend in parallel on a more inward side than the pair of resin sheets positioned on the first extending portion 58. In accordance with this feature, the

check valve

10 or 10A is capable of allowing the fluid to smoothly flow in the forward direction, and further, when the fluid flows in the reverse direction, contact between the pair of main body member side resin sheets 54 in the second extending portion 62 is suitably maintained, and the flow of the fluid can be reliably blocked.

Further, the transitioning portion 60 in which the distance between the pair of resin sheets (the main body member side resin sheets 54) smoothly changes is disposed between the first extending portion 58 and the second extending portion 62. In accordance with this feature, when the fluid flows in the forward direction, the

check valve

10 or 10A is capable of allowing the fluid to flow smoothly, by causing the pair of main body member side resin sheets 54 in the second extending portion 62 to be easily separated.

Further, the opposing surfaces of the pair of resin sheets (the main body member side resin sheets 54) in the second extending portion 62 are formed into smooth surfaces 62a having no unevenness. In accordance with this feature, in the

check valve

10 or 10A, the pair of main body member side resin sheets 54 easily adhere to each other at the second extending portion 62, and the closed state of the opening/closing port member 52 can be intensified.

Further, at the first end 30, the main body member 50 is joined to a connector (the first connector 32) which includes the hollow part 32a communicating with the communication space 51, and is harder than the main body member 50. In accordance with this feature, in the

check valve

10 or 10A, an open state of the communication space 51 can be maintained at the first end 30, and the fluid can be made to smoothly flow into the communication space 51 from the outer side of the first end 30.

Further, at the second end 34, the cover member 40 is joined to a connector (the second connector 36) that is harder than the cover member 40. In accordance with this feature, in the

check valve

10 or 10A, an open state of the accommodation space 41 can be maintained at the second end 34, and the fluid can be made to smoothly flow out from the accommodation space 41 to the outer side of the second end 34.

Further, the cover member 40 is made up from the pair of resin sheets (the cover member side resin sheets 42), and by cutting a joined location of the pair of resin sheets peripherally around the accommodation space 41, includes the cover member side joined portion 44 which is narrower than the accommodation space 41, and the cover member side joined portion 44 is joined to the main body member 50 at the first end 30, while being separated from the lateral sides of the main body member 50. In accordance with this feature, the check valve 10 is capable of temporarily storing the fluid in the accommodation space 41 of the cover member 40, and can more reliably close the main body member 50 when the fluid flows into the accommodation space 41 from the second end 34.

Further, the resin sheets (the cover member side resin sheets 42 and the main body member side resin sheets 54) are formed of at least one selected from among polyvinyl chloride resin, polyurethane resin, and ethylene-vinyl acetate copolymer resin as a primary component. In accordance with this feature, at a time of manufacturing of the

check valve

10 or 10A, the cover member 40 can be suitably molded by carrying out high frequency welding on the cover member side resin sheets 42, and similarly, the main body member 50 can be suitably molded by carrying out high frequency welding on the main body member side resin sheets 54.

Further, the second aspect of the present invention is characterized by the sheet-shaped cassette 70 including, in the interior thereof, the flow path 72 for the fluid by joining together the pair of flexible resin sheets 78 for the cassette, the cassette 70 comprising, in a predetermined position in the flow path 72, the check valve 10A that allows flow of the fluid from the first end 30 to the second end 34, while blocking the fluid from flowing from the second end 34 to the first end 30, and the check valve 10A comprising the cover member 40 constituted by the resin sheets 78 for the cassette and including the accommodation space 41, and the main body member 50 constituted by the flexible main body member side resin sheets 54 and disposed in the accommodation space 41, wherein the main body member 50 includes, on the inner side thereof, the communication space 51 in which the fluid is capable of flowing, and the opening/closing port member 52 that communicates with the communication space 51 and is capable of switching between a communicating state in which the communication space 51 and the accommodation space 41 are in communication, and a blocked state in which communication between the communication space 51 and the accommodation space 41 is blocked, and the main body member 50 is directly or indirectly fixed to the cover member 40 on the side of the first end 30, whereas at least a side of the main body member 50 at a location where the opening/closing port member 52 is formed is separated from the cover member 40. In accordance with this feature, in the cassette 70, by being equipped with the check valve 10A in the interior thereof, the flow direction of the fluid in the flow path 72 can be regulated inside the cassette 70. In addition, the sheet-shaped cassette 70 is capable of being easily molded, manufacturing costs therefor can be significantly reduced, and damage or the like can be suppressed.

Further, the third aspect of the present invention is characterized by the method of manufacturing the check valve 10 or 10A that allows flow of the fluid from the first end 30 to the second end 34, while blocking the fluid from flowing from the second end 34 to the first end 30, the check valve 10 or 10A comprising the cover member 40 constituted by the flexible cover member side resin sheets 42 and including the accommodation space 41, and the main body member 50 constituted by the flexible main body member side resin sheets 54 and disposed in the accommodation space 41, wherein the main body member 50 includes, on the inner side thereof, the communication space 51 in which the fluid is capable of flowing, and the opening/closing port member 52 that communicates with the communication space 51 and is capable of switching between a communicating state in which the communication space 51 and the accommodation space 41 are in communication, and a blocked state in which communication between the communication space 51 and the accommodation space 41 is blocked, and the main body member 50 is directly or indirectly fixed to the cover member 40 on the side of the first end 30, whereas at least a side of the main body member 50 at a location where the opening/closing port member 52 is formed is separated from the cover member 40, the method comprising the first manufacturing step of manufacturing the main body member 50 from a base material (the main body member base material sheets 64) that constitutes the main body member side resin sheets 54, and the second manufacturing step of manufacturing the cover member 40, in a state in which the main body member 50 manufactured by the first manufacturing step is placed on a base material (the cover member base material sheets 48) that constitutes the cover member side resin sheets 42. According to the above-described manufacturing method, the sheet-shaped

check valve

10 or 10A can be easily molded, and manufacturing costs therefor can be significantly reduced.

Claims

A check valve that allows flow of a fluid from a first end to a second end, while blocking the fluid from flowing from the second end to the first end, the check valve comprising:
a cover member constituted by a flexible resin sheet and including an accommodation space; and
a main body member constituted by a flexible resin sheet and disposed in the accommodation space,
wherein the main body member includes, on an inner side thereof, a communication space in which the fluid is capable of flowing, and an opening/closing port member communicating with the communication space and configured to be capable of switching between a communicating state in which the communication space and the accommodation space are in communication, and a blocked state in which communication between the communication space and the accommodation space is blocked, and
the main body member is directly or indirectly fixed to the cover member on a side of the first end, whereas at least a side of the main body member at a location where the opening/closing port member is formed is separated from the cover member.
The check valve according to claim 1, wherein the main body member is made up from a pair of the resin sheets, and both lateral sides thereof are joined from the first end to the opening/closing port member.
The check valve according to claim 2, wherein:
in a side cross-sectional view taken along a thickness direction of the main body member, the main body member includes a first extending portion provided on the side of the first end, and a second extending portion provided on a side of the second end; and
the pair of resin sheets positioned on the second extending portion extend in parallel on a more inward side than the pair of resin sheets positioned on the first extending portion.
The check valve according to claim 3, wherein a transitioning portion in which a distance between the pair of resin sheets smoothly changes is disposed between the first extending portion and the second extending portion.
The check valve according to claim 3 or 4, wherein opposing surfaces of the pair of resin sheets in the second extending portion are formed into smooth surfaces having no unevenness.
The check valve according to any one of claims 1 to 5, wherein, at the first end, the main body member is joined to a connector which includes a hollow part communicating with the communication space, and is harder than the main body member.
The check valve according to any one of claims 1 to 6, wherein, at the second end, the cover member is joined to a connector that is harder than the cover member.
The check valve according to any one of claims 1 to 7, wherein:
the cover member is made up from a pair of the resin sheets, and by cutting a joined location of the pair of resin sheets peripherally around the accommodation space, includes a cover member side joined portion which is narrower than the accommodation space; and
the cover member side joined portion is joined to the main body member at the first end, while being separated from lateral sides of the main body member.
The check valve according to any one of claims 1 to 8, wherein the resin sheets are formed of at least one selected from among polyvinyl chloride resin, polyurethane resin, and ethylene-vinyl acetate copolymer resin as a primary component.
A sheet-shaped cassette including, in an interior thereof, a flow path for a fluid by joining together a pair of flexible resin sheets for the cassette,
the cassette comprising, in a predetermined position in the flow path, a check valve configured to allow flow of the fluid from a first end to a second end, while blocking the fluid from flowing from the second end to the first end, and
the check valve comprising:
a cover member constituted by the resin sheets for the cassette and including an accommodation space; and
a main body member constituted by a flexible main body member side resin sheet and disposed in the accommodation space,
wherein the main body member includes, on an inner side thereof, a communication space in which the fluid is capable of flowing, and an opening/closing port member communicating with the communication space and configured to be capable of switching between a communicating state in which the communication space and the accommodation space are in communication, and a blocked state in which communication between the communication space and the accommodation space is blocked, and
the main body member is directly or indirectly fixed to the cover member on a side of the first end, whereas at least a side of the main body member at a location where the opening/closing port member is formed is separated from the cover member.
A method of manufacturing a check valve that allows flow of a fluid from a first end to a second end, while blocking the fluid from flowing from the second end to the first end,
the check valve comprising a cover member constituted by a flexible cover member side resin sheet and including an accommodation space, and a main body member constituted by a flexible main body member side resin sheet and disposed in the accommodation space;
wherein the main body member includes, on an inner side thereof, a communication space in which the fluid is capable of flowing, and an opening/closing port member communicating with the communication space and configured to be capable of switching between a communicating state in which the communication space and the accommodation space are in communication, and a blocked state in which communication between the communication space and the accommodation space is blocked, and
the main body member is directly or indirectly fixed to the cover member on a side of the first end, whereas at least a side of the main body member at a location where the opening/closing port member is formed is separated from the cover member,
the method comprising:
a first manufacturing step of manufacturing the main body member from a base material that constitutes the main body member side resin sheet; and
a second manufacturing step of manufacturing the cover member, in a state in which the main body member manufactured by the first manufacturing step is placed on a base material that constitutes the cover member side resin sheet.