HK1079131B - Fluid control device - Google Patents

Description

Fluid control device

Technical Field

The present invention relates to a fluid control device for medical use, particularly a fluid control device for infusion therapy, a valve structure of the fluid control device, and a blood pressure measurement system including the fluid control device.

Background

In general, a liquid medicine therapy is performed by introducing a medicine into a blood vessel of a patient or the like via an infusion circuit by means of a container containing the medicine, such as an infusion bag or a syringe filled with the liquid medicine. In this infusion therapy, as shown in fig. 6, the blood pressure of a patient may be measured and monitored simultaneously with the administration of a drug. That is, the conventional infusion circuit is constituted by a syringe 41 filled with a medicine, a syringe pump 4 (medicine supply unit) for pushing out the medicine from the syringe 41, a hose member 7 for carrying the medicine, and a puncture needle 9 provided at the distal end thereof for puncturing a blood vessel of a patient and inputting the medicine. In addition, a mixing and injecting section 8 capable of collecting blood during a treatment process is provided in the middle of the tube member 7 in the infusion circuit. In this infusion circuit, a sensor 5(transducer) is provided in a branch circuit in the middle of a tube member 7 for supplying a drug solution to a human body, and the pressure in the infusion circuit is converted into an electric signal and outputted to a pressure value display device 6. Thus, the medical staff can monitor the blood pressure of the patient at all times by means of the pressure value display device 6 while administering the medicine. However, this blood pressure measurement system has a drawback that when a drug is administered in actual use, the pressure inside the hose member is affected by the pressure fluctuation of the syringe pump 4, and thus the blood pressure cannot be accurately monitored. To overcome this drawback, it is therefore proposed to provide a fluid control device on the way of the sensor 5 and the syringe pump 4 of the circuit. For example, Japanese patent application laid-open No. Hei 1-171527 or Japanese patent application laid-open No. Hei 5-23308 disclose a fluid control device characterized by the following configuration: the fluid supply device has a fluid inlet passage and a fluid outlet passage, and communicates the inlet passage and the outlet passage via a connecting passage having a cross-sectional area smaller than that of each passage, an elastic body is disposed at an end portion of the connecting passage on the outlet passage side, the end portion on the outlet passage side is closed by the elastic body, and when a fluid introduced from the inlet passage reaches a predetermined pressure, the elastic body is pressed to open the end portion on the outlet passage side, and the fluid flows from the inlet passage to the outlet passage.

More specifically, the fluid control device includes a 1 st tubular member having the inlet passage formed therein and a bulging portion at a distal end portion thereof; a 2 nd tubular member fitted around the periphery of the bulging portion to the 1 st tubular member and defining the outlet passage with the bulging portion; the connection path formed on the bulging portion; and a sealing member made of an elastic material covering the bulging portion.

As a fluid control device, a control device used in an X-ray of the infusion circuit shown in fig. 7 is known. The fluid control device used in the X-ray of fig. 7 is integrated with a sensor. The fluid control device is provided with a passage for allowing fluid to flow therethrough, and a control lever capable of changing the size of the passage. The fluid control device is configured such that, in response to the operation of the control lever, the passage diameter of the fluid control device is extremely small during normal use, and the passage diameter is increased during a return operation, thereby increasing the size of the passage used.

In the infusion circuit, blood is taken from a mixing and injecting unit 8 provided in the circuit during the treatment and is examined. In this case, blood remains in the tube member 7 between the patient and the mixed infusion part 8, and blood coagulation is caused even when left, so that blood needs to be returned to the patient. In this blood return operation (generally referred to as a reflux operation), the syringe pump 4 is driven to increase the flow rate of the drug, and the remaining blood is transferred to the patient. In this reflux operation, the pressure in the circuit is once increased by the driving of the syringe pump 4 and is reflected on the pressure value display device 6. Since the medical staff monitors the pressure value display device 6, it is necessary to quickly reduce the blood pressure of the patient to a pressure value that accurately reflects the blood pressure at the end of the reflux operation. However, the fluid control devices described in the above publications take time to resolve the increase in the pressure in the circuit due to the reflux operation, and it is difficult for medical staff to grasp the accurate blood pressure state of the patient. In the fluid control device disclosed in the above publication, the seal member having the cylindrical skirt portion is provided in an extended state so that the connection passage is in close contact with the outer peripheral surface of the bulging portion opened to the outer peripheral surface thereof, and therefore, it is difficult to secure a flow rate in a low pressure range and to secure a flow rate even when the pressure is increased.

In the fluid control device used on the X-ray of fig. 7, since the diameter of the passage is changed by the operation of the lever, the pressure value of the blood pressure of the patient is greatly affected, and it is difficult to obtain an accurate pressure value, for example, because it is a suspicion that the burden is increased on the infant-like patient.

Disclosure of Invention

In view of the above, the fluid control device of the present invention can measure the pressure more accurately and safely, and can quickly measure the pressure value accurately reflecting the blood pressure of the patient and ensure the flow rate in the lower pressure range when the return operation of the infusion circuit or the like is completed. More specifically, the present invention relates to a fluid control device that can be opened by a predetermined fluid pressure, can accurately follow the applied fluid pressure to perform fluid flow, and can ensure a flow rate in a low pressure range without substantially affecting the fluid pressure on the fluid inflow side (outlet side) in accordance with the fluid flow through the device opening.

That is, the present invention provides a fluid control device in which a fluid from a 1 st fluid flow path can flow at a predetermined hydraulic pressure or more, the fluid control device comprising: a hollow 1 st fluid flow path and a 2 nd fluid flow path; a housing portion having a hollow portion with a cross-sectional area larger than that of the two fluid flow paths formed between the 1 st fluid flow path and the 2 nd fluid flow path; and a valve member made of an elastic material, which is attached to an opening portion connecting the first fluid flow path and the hollow portion, and which has a main body and a protruding portion satisfying the following requirements (1) and (2),

(1) the valve member has a main body formed of a tubular member insertable into the 1 st fluid flow path, the tubular member having at least one communicating portion on a side portion thereof for allowing the liquid to flow from the 1 st fluid flow path to the hollow portion,

(2) the protrusion is formed at a distal end portion of the tubular member on the side of the hollow portion, extends toward the inner wall surface of the case portion, and has a cavity portion having a cavity connected to the communication portion on the inner side of the body side, and at least a part of an outer edge portion of the cavity portion is located on the inner wall surface of the case portion, and closes a flow of fluid flowing from the 1 st fluid flow path to the hollow portion at or below a predetermined fluid pressure, but the flow of fluid is allowed to flow when the predetermined fluid pressure is exceeded.

According to the above configuration, the fluid supplied from the 1 st fluid channel 21 flows through the communication portion 313 formed in the concave portion 311 of the main body portion 32 of the valve member 3, and reaches the chamber portion 312. The valve member 3 is pressed toward the hollow portion 13 by the pressure of the flowing liquid. At this time, if the pressure reaches a predetermined pressure, the valve member 3 deforms in the direction of the hollow portion 13, and a gap is formed between the edge end portion of the protruding portion 32 of the valve member 3 and the hollow portion base portion 133. The gap allows the 1 st fluid channel 21 to communicate with the hollow portion 13, thereby enabling fluid flow. Then, if the fluid pressure from the 1 st fluid flow path decreases, the edge end portion 34 of the protrusion 32 and the hollow portion base portion 133 are again brought into close contact by the elastic action of the valve member 3 itself, and the 1 st fluid flow path 21 and the hollow portion 13 are closed. On the other hand, in the fluid control device of the present invention, even when the fluid pressure in the hollow portion 13 increases, no fluid flows through the 1 st fluid flow path side. That is, since the protrusion 32 is provided in the hollow portion 13 and the edge end portion 34 of the protrusion 13 is provided on the hollow portion base portion 133, when the pressure in the hollow portion 13 is high, the protrusion 32 is pressed at the same time, and the adhesion force between the edge end portion 34 of the protrusion 13 and the hollow portion base portion 133 is further increased, so that the sealing property between the hollow portion 13 and the 1 st fluid channel 21 is further ensured.

In the fluid control device, when the fluid flowing through the 1 st fluid flow path reaches a predetermined pressure, since the valve member provided in the fluid control device is pressed, a communication portion through which the fluid can pass from the 1 st fluid flow path to the hollow portion is formed between the valve member and the wall surface of the hollow portion, and, even if the liquid pressure from the 2 nd fluid flow path to the hollow part is increased, the valve member is not opened by the pressure from the 2 nd fluid flow path side, and the interference of the pressure in the hose member connected to the 2 nd fluid flow path is not caused, so that the pressure in the 2 nd fluid flow path can be accurately measured, further, the pressure of the fluid supplied from the drug supply device such as a syringe pump is buffered by the valve member inserted in the 1 st fluid flow path, therefore, the pressure fluctuation of the fluid flowing to the 2 nd fluid flow path side is hardly affected.

The specific structure of the fluid control device of the present invention is described in further detail below.

As shown in fig. 1, the fluid control device of the present invention includes, for example, a fluid control device including a first fluid passage 21 on an upstream side connected to a fluid supply device; a 2 nd fluid flow path 22 on the downstream side; a housing part 1 located between the 1 st and 2 nd fluid flow paths and forming a hollow part 13 larger than the cross-sectional areas of the two fluid flow paths; a body part 31 provided in the 1 st fluid flow path 21 and a protrusion part 32 protruding into the hollow part 13 are formed, and the valve member 3 substantially closes a portion where the 1 st fluid flow path 21 and the hollow part 13 are connected by the protrusion part 32. As described above, the main body portion 31 of the valve member 3 is provided in the 1 st fluid flow path 21 in order to buffer the fluid pressure and effectively reduce the fluid pressure by allowing the fluid flowing from the 1 st fluid flow path 21 to flow through the communication portion 313 having a smaller cross-sectional area. Further, since the protrusion 32 is provided so as to protrude toward the hollow portion 3 in order to properly ensure the directionality of the fluid control device (one-way type), even if the fluid pressure in the hollow portion 13 rises, the protrusion 32 is not pressed against the hollow portion base 133 by the pressure, and the attachment of the edge end portion 34 of the protrusion 32 and the hollow portion base 133, which ensures the sealing property, is released.

Since the outer edge of the protrusion 32 is expanded toward the inner wall surface of the case 1, the entire protrusion edge 34 forming the opening is expanded, and thus a sufficient liquid flow rate through the communication portion can be ensured.

The projecting portion 32 of the valve member 3 provided at the connecting portion between the 1 st fluid channel 21 and the hollow portion 3 has a hollow cavity 312 formed on the main body portion side thereof, so that the fluid pressure transmitted from the 1 st fluid channel 21 to the valve member 3 through the communicating portion 313 can be sufficiently and smoothly applied.

Further, the hollow portion 13 provided in the case 1 has a cross section larger than any of the cross sections of the 1 st and 2 nd fluid flow paths to efficiently perform the exhausting operation (priming operation) in the circuit. Further, the hollow portion 13 is formed in a substantially cylindrical shape on the side of connection with the 1 st fluid channel 21, but the hollow portion 13 on the side of connection with the 2 nd fluid channel is preferably formed in a substantially conical shape with the cavity diameter thereof gradually reduced toward the 2 nd fluid channel 22. Since the shape of the hollow portion 13 on the side connected to the 2 nd fluid flow path 22 is formed in a substantially conical shape, air and air bubbles do not remain even at a portion where the fluid does not stay when the fluid passes.

In the assembly of the fluid control device of the present invention, since the cross-sectional areas of the 1 st and 2 nd fluid flow paths are small, it is preferable to dispose the valve member 3 in the 1 st casing part 11 and then fit the 2 nd casing part 12 in the manufacturing process.

The material of the 1 st shell portion 11 is a soft material having a higher flexibility or a material having a higher heat shrinkage than the material of the 2 nd shell portion. In this way, when connecting the tubular members, the tubular member having high flexibility of the material of the outer member is put on the tubular member having high hardness, and the bonding force between the two members is strong. The material of the 1 st shell portion 11 may be, for example, a polypropylene resin, and the material of the 2 nd shell portion 12 may be, for example, a polycarbonate resin. In particular, the combination of polypropylene as the material for the 1 st shell portion 11 and polycarbonate as the material for the 2 nd shell portion 12 can ensure the leak resistance and pressure resistance of the shell portion 1. Such medical instruments are generally used after sterilization. Upon sterilization thereof, the medical appliance will be subjected to some thermal load. In the above-described structure, particularly, if the material of the 1 st shell portion member has higher flexibility than the material of the 2 nd shell portion, the material of the 1 st shell portion member fitted over the outer surface can obtain stronger bonding force by heat shrinkage through a heat treatment operation such as a sterilization operation, which is very advantageous.

As described above, the fluid control device of the present invention can control the direction (unidirectional) of fluid flow by the valve member, and can arbitrarily select the fluid pressure required for opening the valve member when the fluid is caused to flow in one direction by the directional control (unidirectional). Further, since the opening necessary for the fluid to flow can be obtained even in a low pressure range, and the opening necessary for the fluid to flow formed by the valve member can be formed in a large shape, a sufficient flow rate can be secured in any opening pressure range including the low pressure range.

The fluid control device of the present invention comprises a drug supply device, a sensor for measuring the pressure in a tubular member extending from the drug supply device, and a pressure value display device for displaying a signal output from the sensor as a pressure value, and can accurately measure the pressure, that is, the blood pressure by using a medical circuit, such as an infusion circuit, for measuring and controlling the blood pressure of a patient while administering a drug.

The fluid control function of the fluid control device of the present invention was applied to an animal (dog) 83, and an experiment was performed using a chemical liquid supply circuit as shown in fig. 7.

As shown in fig. 7, one arterial pressure monitoring line is divided into 3 branches, and 1 branch line (X-ray) is provided with a heparin-saline bag (pressurized at 300 mmHg) 80 and a fluid control device 82 (a device for regulating the flow rate of a flow path by operating a lever) integrated with the above sensor. The other two lines (Y and Z lines) are provided with a syringe pump 85, a fluid control device (umbrella-shaped article a)86 of the present invention, and a sensor.

In addition, the test uses two lines of Y and Z lines, and the purpose of the test can be achieved even if any 1 line is used.

The syringe size of the syringe pump 85 was 20mL, and the flow rate was 0.5 mL/h. The waveform change at the time of blood return was observed, and the line Y and Z provided with the umbrella-shaped article a86 were used to perform rapid transport of the infusion pump 85 and the line X provided with the flow control device 82 were used to perform backflow (flush), and the blood pressure waveforms generated by the rapid transport of the infusion pump 85 and the backflow of the backflow device 82 were compared, and the waveforms were compared with each other based on an image indicated by a test viewer (Lab VIEW) 84.

In the chemical liquid supply circuit, the pressure buffering action of the pressure buffering action due to the load of the returned blood was tested by using the fluid control device (umbrella-shaped article a) of the present invention. As a result of the test, in the system using the umbrella-shaped article a shown in line 2 of fig. 8, the pressure was not changed during rapid transport for blood return, but the pressure was greatly changed by the pressure bag in the conventional method.

From the above test results, it can be considered that: the system using the umbrella-shaped article A of the fluid control device of the present invention, as shown by line 1 in FIG. 8, can not only accurately measure the blood pressure of a patient and give a small load to the patient, but also is particularly suitable for use as a fluid control device for infants.

Drawings

Fig. 1 is a longitudinal sectional view of a fluid control device of the present invention. Fig. 1(a) is a longitudinal sectional view along a concave portion of a valve member provided in a fluid control device. Fig. 1(B) is a vertical cross-sectional view taken 90 ° from the cross-sectional direction of fig. (a). Fig. 2(a) is a front view of a valve member of the fluid control device of the present invention, and fig. 2(B) is a bottom view of the valve member as viewed from the main body side thereof. The valve member 3 is composed of a substantially cylindrical body 31 and a substantially hemispherical projection 32, and the valve member 3 is formed in an umbrella shape as a whole. Fig. 3(a) is an enlarged front view of a valve member of the fluid control device of the present invention, fig. 3(B) is an enlarged sectional view of the 1 st shell portion, and fig. 4 is a schematic view of a blood pressure measurement system to which the fluid control device of the present invention is attached. Fig. 5 is a graph showing a change in flow rate due to a pressure load in the fluid control device of the present invention. Fig. 6 is a schematic diagram of a conventional blood pressure measurement system. Fig. 7 is a circuit diagram showing chemical liquid supply for a fluid control function test in the fluid control device according to the present invention. Fig. 8 is a graph showing the results of a fluid control function test using the chemical liquid supply circuit of fig. 7.

The numbers in the above figures are respectively indicated as: 1 shell part, 11 st shell part, 111 tabling part, 12 nd shell part, 2 nd shell part, 121 tabling part, 13 hollow part, 131 cylindrical part, 132 slightly conical part, 133 hollow part base part, 21 st fluid flow path, 1 st fluid flow path, 211 fixing part, 22 nd fluid flow path, 2 nd fluid flow path, 3 valve part, 31 main body part, 311 concave part, 312 cavity part, 313 communication part, 32 protruding part, 33 fixing part, 34 protruding part edge end part, 4 injection pump, 41 syringe, 5 sensor, 6 pressure value display device, 7 hose part, 8 mixing injection part, 9 puncture needle, 10 fluid control device, 80 heparin and physiological saline bag, 82 flow control device which is integrated with the sensor and adjusts the flow path by operating the control lever, 83 animal (dog) for experiment, 84 experiment observation instrument, 85 injection pump, 86 fluid control device (umbrella-shaped object A) of the invention, 87 sensor.

Detailed Description

Embodiment mode 1

As shown in FIG. 1, the tubular body constituting the 1 st fluid channel 21 has its end portion bulged to form the 1 st shell portion 11, and the tubular body constituting the 2 nd fluid channel has its end portion bulged to form the 2 nd shell portion 12. The shell portion 1 is formed by fitting the 2 nd shell portion 12 in the 1 st shell portion 11, and the material of the 1 st shell portion 11 is polypropylene resin and the material of the 2 nd shell portion 12 is polycarbonate resin.

Further, the 1 st casing portion 11 and the 2 nd casing portion 12 are formed with concave-convex fitting portions 111 and 121, respectively, and these fitting portions are fitted to each other, so that the two casing portions are not separated from each other, and the airtightness and pressure resistance in the fluid control device are ensured.

The body 31 of the valve member 3 is formed of a cylindrical member inserted into the 1 st fluid flow path, and on the outer peripheral surface of the cylindrical member, substantially semicircular recesses 311 are provided at two opposing positions across the entire longitudinal direction of the body. The concave portion 311 forms a communication portion 313 through which the fluid from the 1 st fluid channel 21 flows. At the same time, a hollow cavity 312 connected to the communication portion 313 is formed inside the protruding portion 32 of the valve member 3. In addition, although this embodiment shows an embodiment in which the concave portions 311 are provided at two locations, the present invention is not limited to this embodiment. For example, the effect of the present invention can be sufficiently achieved by providing the recess 311 at one location or at two or more locations.

The fluid, that is, the liquid from the 1 st fluid channel 21 reaches the chamber 312 through the communication portion 313. At this time, fluid pressure is applied to the cavity 312, and the protruding portion 32 of the valve member 3 is pressed toward the hollow portion, and due to this pressing, a gap is generated between the edge end portion 34 of the protruding portion 32 and the hollow portion base portion 133, which ensure sealing, of the opening portion provided on the hollow portion 32 side of the 1 st fluid flow path 21, so that the opening portion is formed, and the fluid flows toward the hollow portion 32 side.

Since the cavity 312 having a substantially hemispherical hollow shape is formed on the main body portion side of the valve member 3, the area to which the fluid pressure is applied from the 1 st fluid flow path 21 to the valve member 3 through the communicating portion 313 is increased, and the liquid introduced into the communicating portion can be easily guided to the opening portion through which the liquid flows.

The length (b in fig. 1) from the edge end of the protruding portion provided at the portion connected to the hollow portion 13 of the 1 st fluid flow path 21 to the inner wall surface of the housing portion 1 is preferably 1.5mm to 5 mm. When the length is less than 1.5mm, the volume in the hollow portion 13 becomes small, and it is difficult to efficiently discharge air or air bubbles in the operation (priming operation) for filling the drug and removing air in the circuit before the use of the infusion path using the fluid control device of the present invention. On the other hand, if the distance b exceeds 5mm, the volume of the hollow portion 13 increases, which not only increases the size of the entire apparatus but also increases the amount of liquid to be introduced unnecessarily.

Further, in the valve member 3 of the present embodiment, as shown in fig. 1, since the edge end portion 34 is seated on the hollow portion base portion 133 constituting the 1 st fluid flow path bulging portion, the 1 st fluid flow path 21 and the hollow portion 13 are kept sealed against the flow of liquid at a predetermined liquid pressure or lower.

Further, since the shape of the projection 32 of the valve member 3 is a structure having an arc-shaped substantially semicircular spherical shape toward the 2 nd fluid flow path side, the liquid flowing from the 1 st fluid flow path through the hollow portion to the 2 nd fluid flow path can be smoothly and sufficiently guided to the vicinity of the opening portion through which the liquid passes.

According to the function of the valve member 3 described above, the fluid control device of the present invention can open and close accurately following a predetermined fluid pressure applied thereto, and can obtain an open/close control mechanism through which a fluid flow can pass even in response to a low-pressure fluid pressure from the 1 st fluid flow path 21.

The valve member 3 has a fixing portion 33 formed at an end opposite to the protruding portion 32 of the body 31. And a fixing portion 211 which can be joined to the fixing portion 33 is formed in the 1 st fluid channel 21.

Further, since the two fixing portions are joined, not only is it easy to attach and detach the valve member 3 to and from the housing 1, but also the fixing structure can adjust the force of fitting and setting the valve member 3 to the hollow portion base 133, and therefore, the liquid flow sealing property of the valve member 3 can be ensured reliably.

That is, as shown in fig. 3, the length (c) of the body 31 and the length (d) from the fixed portion of the 1 st fluid channel 21 to the hollow portion base 133 are (c) < (d). By satisfying the main condition (c) < (d), the valve member 3 is attached to the hollow portion base 133, and the valve member 3 is disposed in the longitudinal direction of the 1 st case portion 11, so that the sealing property can be more reliably ensured.

The relationship between the length (c) and the length (d) may be appropriately selected depending on the application. For example, the smaller the difference between the length (c) and the length (d), the lower the adhesion force of the valve member 3 and the lower the pressure required to form the opening between the valve member 3 and the hollow portion base 133, and conversely, the larger the difference between the length (c) and the length (d), the stronger the adhesion force of the valve member 3 and the larger the pressure required to form the opening between the valve member 3 and the hollow portion base 133.

In particular, the above-mentioned relationship between (c) and (d) is preferably 1: 1 to 1: 1.25 for (c) to (d), or 1.45mm for (c) and 1.45 to 1.8mm for (d). Satisfying such a condition, the fluid pressure can be made less than 0.2Kgf/cm²And a fluid control device capable of flowing the fluid flowing from the 1 st fluid channel to the 2 nd fluid channel while exerting a buffer action without affecting the pressure in the 2 nd fluid channel.

And the valve member 3 is preferably an elastic member. Such as:

it is preferable that the rubber composition is composed of various rubber materials such as natural rubber, isoprene rubber, butadiene rubber, styrene-butadiene rubber, nitrile rubber, chloroprene rubber, butyl rubber, acrylic rubber, ethylene-propylene rubber, alcohol (hydrin) rubber, urethane rubber, silicone rubber, and fluororubber, and various thermoplastic elastic rubbers such as styrene, polyolefin, polyvinyl chloride, polyurethane, polyester, polyamide, polybutadiene, trans-polyisoprene, fluororubber, and chlorinated polyethylene.

In particular, the valve member 3 is preferably made of silicone rubber. Silicone rubber is sufficiently elastic to obtain the required resilience of the valve member, and silicone is also very resistant to medication.

In medical devices, if an adhesive organic solvent is used, it may be dissolved into the drug, and safety may not be ensured, which makes it inconvenient to use. However, the fluid control device of the present embodiment is configured by only fitting the 1 st case member 11 and the 2 nd case member 12 without using an adhesive. The fluid control device is ideal in that it does not use an adhesive.

Embodiment mode 2

Fig. 4 is a schematic diagram of a blood pressure measurement system in which the fluid control device of the present invention is installed, and measures blood pressure while performing infusion therapy. As follows: by installing the fluid control device of the present invention on an infusion therapy circuit, the pressure in the circuit is not changed by installing the fluid control device, and the pressure of the fluid flowing through the circuit can be measured more accurately, and the return operation can be completed in a short time, so that any alarm setting level of an alarm device installed on the circuit can be easily dealt with.

The medication delivered from the syringe 41 by driving the syringe pump 4 is injected into a blood vessel or the like of the patient via the hose member 7 and a puncture needle provided at the tip thereof. At this time, a branch line is provided midway in the hose member 7, and the sensor 5 is provided on the branch line to measure the fluid pressure. The pressure signal detected by the sensor 5 can be observed as a waveform of the pressure value on a pressure value display device 6 connected thereto, and can be monitored by a medical worker. The fluid control device 10 is provided in a circuit upstream of the sensor 5 (with respect to the syringe pump 4). By providing the fluid control device 10, the pressure can be measured more accurately. That is, the fluid control device 10 can alleviate the pressure rise caused by the syringe pump type medicine supply device located on the upstream side of the circuit, and does not substantially affect the pressure of the fluid on the downstream side (the circuit side where the sensor 5 is provided), and the fluid control device 10 is characterized in that the fluid flows only in one direction, so that the fluid pressure in the circuit where the fluid control device 10 is provided is not disturbed by the fluid control device, and pressure fluctuation is not generated.

On the other hand, during the treatment, blood may be collected from the mixing and injecting unit 8 provided in the circuit for examination. At this time, blood remains in the tube member 7 between the puncture needle 9 and the mixed injection part 8, and blood needs to be returned to the patient side regardless of the coagulation caused by the placement. This blood return operation (generally referred to as a reflux operation) returns residual blood to the patient by driving the syringe pump 4 at a relatively high flow rate (a rapid-sending operation). The syringe pump 4 is usually operated at 0.3Kgf/cm for a rapid operation²The fluid control device 10 can ensure a large flow rate, and therefore the reflux can be performedThe operation is completed in a short time, and thus is very advantageous. That is, FIG. 5 shows a flow rate change table due to the pressure load of the fluid control apparatus of the present invention, but 0.3Kgf/cm is generated by the rapid operation of the syringe pump 4²The fluid control device of the present invention can secure a flow rate of 80ml/min or more in pressure. However, if the pressure generated by the quick feed operation of the syringe pump 4 is reduced to the pressure at the time of normal use after the completion of the reflux operation, the flow rate can be rapidly reduced by the fluid control device of the present invention, and therefore, the pressure fluctuation on the downstream side is hardly affected. Further, since the backflow operation has an advantage that it can be completed in a short time, the time for the downstream side to rise due to the backflow operation is also completed in a short time, which is very advantageous for medical staff to accurately monitor the pressure change.

As a detection device for detecting the occurrence of a blockage in the flow path of the injection pump during normal use, there is a mechanism for issuing an alarm when a predetermined pressure is reached. The pressure setting detected by a general syringe pump is variable, and the minimum value of the alarm setting level of a commonly used syringe pump is 0.2Kgf/cm²On the other hand, if the water pressure of the fluid control device exceeds 0.2Kgf/cm²An alarm is issued, which is not good. However, even if the alarm set pressure is required to be less than the above-mentioned 0.2Kgf/cm²When the pressure is low, the pressure is lower than 0.2Kgf/cm²When the pressure is low, the valve member of the fluid control device is opened to allow a sufficient amount of fluid to flow before the alarm is issued, and therefore, the sufficient amount of fluid can be circulated without issuing the alarm as described above, and the occurrence of an abnormal state can be reliably detected by the mechanism for issuing the alarm, so that the safety therapy (the infusion therapy in the present embodiment) can be effectively performed. However, the water pressure of the fluid control device of the present invention is even higher than 0.2Kgf/cm²Either a low level of water pressure or a high level of water pressure. For example, the amount of the inorganic filler may be about 0.1 to 0.5Kgf/cm²Left and right pressure.

The present embodiment has been described with reference to infusion therapy as an ideal embodiment. The fluid control devices of the present invention may also work equally well in circuits for other therapies.

Possibility of industrial utilization

The fluid control device of the invention can be opened under a specified pressure to circulate the fluid, and the fluid pressure required by the opening can be easily set. Further, the fluid control device of the present invention can ensure a flow rate even if the applied pressure is a low pressure, and the fluid can flow while following the applied pressure accurately, so that the flow rate can be controlled in a low pressure range, and the fluid pressure on the fluid inflow side (outlet side) is not substantially affected by the fluid flow with the device opened. Further, the fluid control device of the present invention can provide a fluid control device that measures pressure more accurately and safely, or a blood pressure measurement system using the fluid control device.

Claims (9)

1. A fluid control device, characterized by comprising:

a hollow 1 st fluid flow path and a 2 nd fluid flow path;

a shell portion formed between the 1 st fluid flow path and the 2 nd fluid flow path, and having a hollow portion with a cross-sectional area larger than that of the two fluid flow paths; and

a valve member made of an elastic material, and satisfying the following requirements (1) to (4) so that the liquid from the 1 st fluid flow path can be made to flow to the casing at a predetermined liquid pressure or higher,

(1) the valve member includes a main body portion insertable into an upper opening portion side of the 1 st fluid flow path, and a protrusion portion connected to the main body portion and provided in the casing portion,

(2) the main body portion is formed of a tubular member having a communicating portion formed of at least one recess portion at a side portion thereof, the communicating portion being capable of allowing a liquid to flow from the 1 st fluid flow path to the shell portion,

(3) the protrusion is disposed in a direction facing a fluid flow from the 1 st fluid flow path, and is directed toward the 2 nd fluid flow path connected to the communication portion on the main body side of the protrusion, and has a semi-spherical cavity portion, and at least a part of an outer edge portion of the protrusion is located on an inner wall bottom surface of the case portion, and closes a flow of the fluid flowing from the 1 st fluid flow path to the hollow portion when a predetermined fluid pressure is not higher than a predetermined fluid pressure, but deforms the outer edge portion seated on the case portion by the fluid pressure when the predetermined fluid pressure is exceeded, and allows the fluid flow to flow therethrough,

(4) a fixing portion is formed at an end portion of the valve member on the opposite side to the projecting portion, and a fixing portion engageable with a fixing portion formed at an end portion of the valve member main body on the opposite side to the projecting portion is formed in the 1 st fluid flow path.

2. The fluid control device according to claim 1, wherein the valve member main body portion is provided to be stretched in a longitudinal direction of the 1 st fluid flow path.

3. The fluid control device according to claim 1, wherein the fluid pressure F is less than 0.2Kgf/cm²The valve member is opened, the 1 st fluid flow path and the hollow portion can flow.

4. The fluid control device according to claim 1 or 2, wherein the cavity of the hollow portion on the 2 nd fluid flow path side has a substantially conical shape whose inner diameter is gradually reduced from the 1 st fluid flow path side to the 2 nd fluid flow path side.

5. The fluid control device according to claim 4, wherein the case member is constituted by a 1 st case member in which a distal end of the 1 st fluid flow path is formed bulging, and a 2 nd case member in which a distal end of the 2 nd fluid flow path is formed bulging, and the two case members are constituted not by using an adhesive but by fitting.

6. The fluid control device according to claim 5, wherein the bulge portion of the 2 nd fluid flow path is embedded in the bulge portion of the 1 st fluid flow path to constitute the shell portion.

7. The fluid control device according to claim 6, wherein the material of the 1 st shell member has a greater thermal shrinkage than the material of the 2 nd shell member.

8. A medicine supply circuit comprising at least: a medicine supply device; a tubular member through which the medicine delivered from the medicine supply device flows; a drug administration device for administering a drug to a human body via the tubular member; a sensor for determining a pressure within the tubular member; pressure value display means for displaying a signal output from the sensor as a pressure value,

the chemical supply circuit uses the fluid control device according to any one of claims 1 to 7 as a fluid control device.

9. The medication supply circuit of claim 8 wherein the medication supply circuit is an infusion circuit and the pressure value display device is a blood pressure value display device.