WO1991016609A1 - Device for detecting inner pressure conditions in flexible ducts - Google Patents

Device for detecting inner pressure conditions in flexible ducts Download PDF

Info

Publication number
WO1991016609A1
WO1991016609A1 PCT/EP1991/000761 EP9100761W WO9116609A1 WO 1991016609 A1 WO1991016609 A1 WO 1991016609A1 EP 9100761 W EP9100761 W EP 9100761W WO 9116609 A1 WO9116609 A1 WO 9116609A1
Authority
WO
WIPO (PCT)
Prior art keywords
line
pressure
movable plate
detection
pressure sensor
Prior art date
Application number
PCT/EP1991/000761
Other languages
German (de)
French (fr)
Inventor
F. Baldo Veracchi
Original Assignee
Infurex Ag
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to KR1019910701705A priority Critical patent/KR920701861A/en
Application filed by Infurex Ag filed Critical Infurex Ag
Publication of WO1991016609A1 publication Critical patent/WO1991016609A1/en

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L9/00—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means
    • G01L9/0001—Transmitting or indicating the displacement of elastically deformable gauges by electric, electro-mechanical, magnetic or electro-magnetic means
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
    • A61M1/00—Suction or pumping devices for medical purposes; Devices for carrying-off, for treatment of, or for carrying-over, body-liquids; Drainage systems
    • A61M1/36—Other treatment of blood in a by-pass of the natural circulatory system, e.g. temperature adaptation, irradiation ; Extra-corporeal blood circuits
    • A61M1/3621—Extra-corporeal blood circuits
    • A61M1/3639—Blood pressure control, pressure transducers specially adapted therefor
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
    • A61M5/00—Devices for bringing media into the body in a subcutaneous, intra-vascular or intramuscular way; Accessories therefor, e.g. filling or cleaning devices, arm-rests
    • A61M5/14—Infusion devices, e.g. infusing by gravity; Blood infusion; Accessories therefor
    • A61M5/168—Means for controlling media flow to the body or for metering media to the body, e.g. drip meters, counters ; Monitoring media flow to the body
    • A61M5/16831—Monitoring, detecting, signalling or eliminating infusion flow anomalies
    • A61M5/16854—Monitoring, detecting, signalling or eliminating infusion flow anomalies by monitoring line pressure

Definitions

  • the invention relates to a device for detecting the internal pressure conditions in flexible lines, preferably in tubular or pillow-shaped lines or flexible containers of medical technology, according to the preamble of claim 1.
  • a generic device for detecting the internal pressure conditions in flexible lines is known from US-A-33 76 750.
  • the device according to the invention it is possible on the one hand to maintain a high measuring sensitivity, but on the other hand to take into account the residual elasticity of the deformed lines, since the provision of the detection device intercepts the residual elasticity. There is the possibility for this after a short initial phase
  • the restoring force of the comfortable curved edge areas is determined in the transition period between the elastic and plastic deformation. This enables the determination of characteristic curves which reflect a base pressure, on the basis of which the measurement of the internal pressure conditions takes place. In other words, there is the possibility of preventing the internal pressure measurement results from being falsified by the deformation of the line.
  • the movable plate is preferably so light and is guided so smoothly that the weight of the movable plate and the friction losses in the guide are practically negligible.
  • a plunger On the side of the plate facing away from the line, a plunger is preferably attached, which can be provided with a convex support tip, the radius of curvature of which can be adapted depending on the application.
  • the plunger acts on the membrane of a sufficiently sensitive pressure sensor.
  • the above-mentioned curvature of the plunger tip can be used to influence the characteristic curve of the pressure sensor resolution.
  • the device according to the present invention it is in principle also possible for the device according to the present invention to be restricted to a single hose type, the characteristic of which is then stored as the only characteristic in the device.
  • FIG. 1 shows a schematically greatly simplified sectional illustration of the device according to the invention.
  • FIG. 2 shows a diagram to explain the mode of operation of a detection device of the device according to the invention.
  • the device 1 shows an embodiment of a device 1 according to the invention for detecting the internal pressure conditions in flexible lines in a greatly simplified representation. shows.
  • the device 1 according to the invention is particularly suitable for recognizing the internal pressure conditions in the case of hose-like or pillow-shaped flexible lines or containers of medical technology, since it has a very high sensitivity, which is required above all for medical purposes.
  • the device 1 has a pressure sensor 2, which can be designed in a conventional manner and comprises a pressure-receiving surface 3.
  • the device 1 has a transmission device 4, which effectively couples a line 5, the internal pressure conditions of which are to be recorded, to the pressure sensor 2.
  • the transmission device 4 of the device 1 comprises an immovable or stationary plate 6, which can be, for example, the part of a cover which can be folded up and down in a housing of the device 1 which is not shown in detail. Furthermore, the transmission device 4 has a movable plate 7, which is guided with low friction in the housing (not shown in detail) and is made as light as possible.
  • the movable plate 7 is connected to a plunger 8 on its side facing away from the line or container 5.
  • the plunger 8 preferably has a circular cross section and is connected at its free end to a convex contact part or head 9.
  • the curved end face region 10 can vary in its convexity. In any case, it is designed so that there is a point support of the system part 9 on the surface 3 of the pressure sensor 2.
  • the movable plate 7 In order to guide the movable plate 7 with as little friction as possible, it is in the embodiment shown in FIG. 1 guided via their plunger 8 in a sliding guide or sliding bearing 11, which can also be part of the housing.
  • Fig. 1 shows that the line 5 is clamped between the plates 6 and 7. This results in a prestressing of the line 5 in such a way that two wall sections 12 and 13 arranged essentially parallel to one another are formed. This type of prestressing increases the area of attack for the internal pressure of the line 5, so that a pressure transformation results on the sensor 2, since the plunger or its contact part 9 create an at least essentially punctiform support on the pressure sensor 2.
  • FIG. 1 shows that when the internal pressure of the line 5 is increased, the movable plate 7 is moved essentially in a direction which is perpendicular to the wall sections 12 and 13.
  • the device 1 according to the invention can also be provided with a shut-off device, not shown in FIG. 1, which completely blocks the line 5 if necessary.
  • the shut-off device 5 can preferably be connected to the pressure sensor 2 or to an evaluation unit and control device evaluating its signals, so that it is actuated or released by this control device when necessary.
  • the shut-off device may be necessary for safety reasons, for example in the field of medical technology, if it is necessary, for example, to shut off line 5 when certain pressure conditions occur, because this line is an infusion line or the like. represents.
  • the device 1 according to the invention is further provided with a detection device (not shown in detail), the function of which, however, results from the illustration in FIG. 2.
  • a detection device (not shown in detail), the function of which, however, results from the illustration in FIG. 2.
  • 1 are three basic pressure characteristic curves B, B and B are shown by way of example.
  • This base pressure characteristics 1 symbolize under ⁇ Kunststoffliche conductivity types, gene whose characteristics especially on the materials used and abscon ⁇ dimensions.
  • A can be determined, for example, by means of a mathematical model, on the basis of which the detection device, after determining the initial gradient G,
  • FIG. 1 some pressure surges are shown as an example to clarify the internal pressure measurement, which are illustrated as deflections on the basis pressure characteristic curves B to B.
  • the detection device can be provided with a memory which is loaded with experimentally determined characteristic curves of a large number of different lines, hoses or containers, so that a comparison can be made between the recorded geometric function and the stored characteristic curve what type of hose it is.
  • Device (1) for detecting the internal pressure conditions in flexible lines preferably hose-shaped or pillow-shaped flexible lines or containers of medical technology
  • the transmission device (4) having an immovable and a movable plate (6 or 7) between which the line (5) is arranged under prestress, the movable plate (7) effecting the coupling to the pressure sensor (2),
  • a detection device which determines the type of line by determining the restoring force in the transition period from the elastic state to the plastic state.
  • shut-off device can be actuated as a function of the measured pressure.
  • a unit is done. 13.
  • Device according to item 1 or 2 in which, for recognition, a comparator device is carried out for comparison between the determined pressure curve and experimentally determined pressure curves of different line types previously entered in a memory device.

Abstract

A device (1) for detecting inner pressure conditions in flexible ducts (5) has a fixed plate (6) and a movable plate (7) between which the duct (5) is pre-stressed. The inner pressure conditions are transmitted by the movable plate (7), if necessary by a tappet (8), to a pressure sensor (2). This device (1) is highly sensitive and allows inner pressure conditions to be directly measured from outside without any accessory implements.

Description

Vorrichtung zur Erkennung der Innendruckverhältnisse in flexiblen Leitungen Device for detecting the internal pressure conditions in flexible lines
Beschreibungdescription
Die Erfindung betrifft eine Vorrichtung zur Erkennung der Innendruckverhältnisse in flexiblen Leitungen, vorzugsweise in schlauch- oder kissenförmigen Leitungen bzw. flexiblen Containern der Medizin-Technik, nach dem Oberbegriff des An¬ spruches 1.The invention relates to a device for detecting the internal pressure conditions in flexible lines, preferably in tubular or pillow-shaped lines or flexible containers of medical technology, according to the preamble of claim 1.
Eine gattungsgemäße Vorrichtung zur Erkennung der Innen¬ druckverhältnisse in flexiblen Leitungen ist aus der US-A-33 76 750 bekannt.A generic device for detecting the internal pressure conditions in flexible lines is known from US-A-33 76 750.
Diese Vorrichtung ist jedoch zunächst insofern nachteilig, als ihr Aufbau relativ aufwendig ist. Ferner können sich Verfälschungen der Innendruckmeßergebnisse durch die Verformung der Leitung ergeben, die bei der bekannten Vorrichtung durch das Einklemmen der Leitung zwischen zwei Platten hervorgerufen wird.However, this device is initially disadvantageous in that its construction is relatively complex. Furthermore, the internal pressure measurement results can be falsified by the deformation of the line, which is caused in the known device by the line being clamped between two plates.
Es ist daher Aufgabe der vorliegenden Erfindung, eine Vorrichtung zur Erkennung der Innendruckverhältnisse in flexiblen Leitungen nach dem Oberbegriff des Anspruchs 1 zu schaffen, die bei Aufrechterhaltung einer hohen Meßempfindlichkeit durch Verformung der zu untersuchenden Leitung die Vermeidung von Verfälschungen der Innendruckmeßergebnisse ermöglicht. Die Lösung dieser Aufgabe erfolgt durch die Merkmale des Anspruches 1.It is therefore an object of the present invention to provide a device for detecting the internal pressure conditions in flexible lines according to the preamble of claim 1, which, while maintaining a high level of sensitivity by deformation of the line to be examined, makes it possible to avoid falsifications of the internal pressure measurement results. This object is achieved by the features of claim 1.
Mit der erfindungsgemäßen Vorrichtung ist es einerseits möglich, eine hohe Meßempfindlichkeit aufrechtzuerhalten, andererseits jedoch die Restelastizität der verformten Lei¬ tungen zu berücksichtigen, da das Vorsehen der Erkennungs¬ einrichtung die Restelastizität abfängt. Es ergibt sich hierfür die Möglichkeit, nach einer kurzen AnfangsphaseWith the device according to the invention it is possible on the one hand to maintain a high measuring sensitivity, but on the other hand to take into account the residual elasticity of the deformed lines, since the provision of the detection device intercepts the residual elasticity. There is the possibility for this after a short initial phase
die geometrische Funktion, nach der die elastische Verfor¬ mung in eine plastische übergeht, zu ermitteln. Hierzu wird die Rückstellkraft der verfortem gekrümmten Randbereiche in der Übergangszeit zwischen der elastischen und plastischen Verformung ermittelt. Dies ermöglicht die Ermittlung von Kennlinien, die einen Basisdruck widergeben, auf dessen Grundlage die Messung der Innendruckverhältnisse erfolgt. Es ergibt sich mit anderen Worten die Möglichkeit, eine Verfäl¬ schung der Innendruckmeßergebnisse durch die Verformung der Leitung zu verhindern.to determine the geometric function, after which the elastic deformation changes into a plastic one. For this purpose, the restoring force of the comfortable curved edge areas is determined in the transition period between the elastic and plastic deformation. This enables the determination of characteristic curves which reflect a base pressure, on the basis of which the measurement of the internal pressure conditions takes place. In other words, there is the possibility of preventing the internal pressure measurement results from being falsified by the deformation of the line.
In den Unteransprüchen sind vorteilhafte Weiterbildungen der Erfindung angegeben-Advantageous developments of the invention are specified in the subclaims.
Mit der Erfindung wird somit eine Vorrichtung geschaffen, deren bewegliche Platte vorzugsweise so leicht ist und so leichtgängig geführt wird, daß das Gewicht der beweglichen Platte und die Reibungsverluste bei der Führung praktisch vernachlässigbar sind.With the invention, a device is thus created, the movable plate is preferably so light and is guided so smoothly that the weight of the movable plate and the friction losses in the guide are practically negligible.
An der der Leitung abgewandten Seite der Platte ist vorzugs¬ weise ein Stößel angebracht, der mit einer konvexen Auflage¬ spitze versehen sein kann, deren Krümmungsradius je nach An¬ wendungsfall anpaßbar ist. Der Stößel wirkt hierbei auf die Membran eines genügend empfindlichen Drucksensors ein. Durch die Transformation des Flächendruckes, der an der Kontakt¬ stelle zwischen der Leitung, die sich bei Zunahme des Innen¬ druckes nach außen wölbt, und der beweglichen Platte sowie der Punktauflage des konvexen Stößels der Membran des Druck¬ sensors gegenüber entsteht, wird unter Berücksichtigung der Verhältnisse, insbesondere der Leitungscharakteristiken, ausreichend Kraft geschaffen, um den Drucksensor zu betäti¬ gen.On the side of the plate facing away from the line, a plunger is preferably attached, which can be provided with a convex support tip, the radius of curvature of which can be adapted depending on the application. The plunger acts on the membrane of a sufficiently sensitive pressure sensor. By the transformation of the surface pressure that arises at the contact point between the line, which bulges outwards as the internal pressure increases, and the movable plate and the point contact of the convex tappet opposite the membrane of the pressure sensor is taken into account in the Conditions, in particular the line characteristics, created sufficient force to actuate the pressure sensor.
Die zuvor angesprochene Krümmung der Stößelspitze kann hier¬ bei zur Kennlinienbeeinflussung der Drucksensorauflösung herangezogen werden.The above-mentioned curvature of the plunger tip can be used to influence the characteristic curve of the pressure sensor resolution.
Als Alternative zur Bestimmung der elastischen Verformung unterschiedlicher Schlauchtypen ist es jedoch grundsätzlich auch möglich, daß die Vorrichtung gemäß vorliegender Erfin¬ dung auf einen einzigen Schlauchtyp beschränkt wird, dessen Kennlinie dann als einzige Kennlinie in der Vorrichtung ge¬ speichert wird.As an alternative to determining the elastic deformation of different hose types, however, it is in principle also possible for the device according to the present invention to be restricted to a single hose type, the characteristic of which is then stored as the only characteristic in the device.
Weitere Einzelheiten, Merkmale und Vorteile der Erfindung ergeben sich aus nachfolgender Beschreibung eines Ausfüh¬ rungsbeispiels anhand der Zeichnung.Further details, features and advantages of the invention result from the following description of an exemplary embodiment with reference to the drawing.
Es zeigt:It shows:
Fig. 1 eine schematisch stark vereinfachte Schnittdarstel¬ lung der erfindungsgemäßen Vorrichtung, und1 shows a schematically greatly simplified sectional illustration of the device according to the invention, and
Fig. 2 ein Diagramm zur Erläuterung der Wirkungsweise ei¬ ner Erkennungseinrichtung der erfindungsgemäßen Vorrichtung.2 shows a diagram to explain the mode of operation of a detection device of the device according to the invention.
In Fig. 1 ist eine Ausführungsform einer erfindungsgemäßen Vorrichtung 1 zur Erkennung der Innendruckverhältnisse in flexiblen Leitungen in stark vereinfachter Darstellung ge- zeigt. Die erfindungsgemäße Vorrichtung 1 ist insbesondere zur Erkennung der Innendruckverhältnisse bei schlauch- oder kissenförmigen flexiblen Leitungen bzw. Containern der Medi¬ zin-Technik geeignet, da sie eine sehr hohe Empfindlichkeit hat, die vor allem für medizinische Zwecke erforderlich ist.1 shows an embodiment of a device 1 according to the invention for detecting the internal pressure conditions in flexible lines in a greatly simplified representation. shows. The device 1 according to the invention is particularly suitable for recognizing the internal pressure conditions in the case of hose-like or pillow-shaped flexible lines or containers of medical technology, since it has a very high sensitivity, which is required above all for medical purposes.
Die Vorrichtung 1 weist einen Drucksensor 2 auf, der in üb¬ licher Art und Weise ausgebildet sein kann und eine Druck¬ aufnahmefläche 3 umfaßt.The device 1 has a pressure sensor 2, which can be designed in a conventional manner and comprises a pressure-receiving surface 3.
Ferner weist die Vorrichtung 1 eine Übertragungseinrichtung 4 auf, die eine Leitung 5, deren Innendruckverhältnisse zu erfassen sind, wirkungsmäßig mit dem Drucksensor 2 koppelt.Furthermore, the device 1 has a transmission device 4, which effectively couples a line 5, the internal pressure conditions of which are to be recorded, to the pressure sensor 2.
Die Übertragungseinrichtung 4 der erfindungsgemäßen Vorrich¬ tung 1 umfaßt eine unbewegliche bzw. stationäre Platte 6, die beispielsweise der Teil eines auf- und abklappbaren Dek- kels eines nicht näher dargestellten Gehäuses der Vorrich¬ tung 1 sein kann. Ferner weist die Übertragungseinrichtung 4 eine bewegliche Platte 7 auf, die im nicht näher dargestell¬ ten Gehäuse reibungsarm geführt und möglichst leicht ausge¬ bildet ist.The transmission device 4 of the device 1 according to the invention comprises an immovable or stationary plate 6, which can be, for example, the part of a cover which can be folded up and down in a housing of the device 1 which is not shown in detail. Furthermore, the transmission device 4 has a movable plate 7, which is guided with low friction in the housing (not shown in detail) and is made as light as possible.
Bei der dargestellten Ausführungsform ist die bewegliche Platte 7 an ihrer der Leitung bzw. dem Container 5 abgewand¬ ten Seite mit einem Stößel 8 verbunden. Der Stößel 8 weist vorzugsweise kreisförmigen Querschnitt auf und ist an seinem freien Ende mit einem konvexen Anlageteil bzw. Kopf 9 ver¬ bunden. Der gekrümmte Stirnflächenbereich 10 kann in seiner Konvexität variieren. Er wird in jedem Falle so ausgebildet, daß es zu einer Punktauflage des Anlageteiles 9 auf der Flä¬ che 3 des Drucksensors 2 kommt.In the embodiment shown, the movable plate 7 is connected to a plunger 8 on its side facing away from the line or container 5. The plunger 8 preferably has a circular cross section and is connected at its free end to a convex contact part or head 9. The curved end face region 10 can vary in its convexity. In any case, it is designed so that there is a point support of the system part 9 on the surface 3 of the pressure sensor 2.
Zur möglichst reibungsarmen Führung der beweglichen Platte 7 ist diese bei der in Fig. 1 dargestellten Ausführungsform über ihren Stößel 8 in einer Gleitführung bzw. Gleitlagerung 11 geführt, die ebenfalls Teil des Gehäuses sein kann.In order to guide the movable plate 7 with as little friction as possible, it is in the embodiment shown in FIG. 1 guided via their plunger 8 in a sliding guide or sliding bearing 11, which can also be part of the housing.
Fig. 1 zeigt, daß die Leitung 5 zwischen den Platten 6 und 7 eingespannt ist. Hieraus resultiert eine Vorspannung der Leitung 5 der Art, daß zwei im wesentlichen parallel zuein¬ ander angeordnete Wandabschnitte 12 und 13 gebildet werden. Diese Art der Vorspannung vergrößert die Angriffsfläche für den Innendruck der Leitung 5, so daß sich eine Drucktrans¬ formation auf den Sensor 2 ergibt, da der Stößel bzw. dessen Anlageteil 9 eine zumindest im wesentlichen punktförmige Auflage auf dem Drucksensor 2 schaffen.Fig. 1 shows that the line 5 is clamped between the plates 6 and 7. This results in a prestressing of the line 5 in such a way that two wall sections 12 and 13 arranged essentially parallel to one another are formed. This type of prestressing increases the area of attack for the internal pressure of the line 5, so that a pressure transformation results on the sensor 2, since the plunger or its contact part 9 create an at least essentially punctiform support on the pressure sensor 2.
Ferner verdeutlicht die Darstellung der Fig. 1, daß bei Er¬ höhung des Innendruckes der Leitung 5 die bewegliche Platte 7 im wesentlichen in einer Richtung bewegt wird, die senk¬ recht zu den Wandabschnitten 12 und 13 steht.Furthermore, the illustration in FIG. 1 shows that when the internal pressure of the line 5 is increased, the movable plate 7 is moved essentially in a direction which is perpendicular to the wall sections 12 and 13.
Die erfindungsgemäße Vorrichtung 1 kann ferner mit einer in Fig. 1 nicht näher dargestellten Absperreinrichtung versehen sein, die im Bedarfsfalle die Leitung 5 vollständig blok- kiert. Vorzugsweise kann die Absperreinrichtung 5 mit dem Drucksensor 2 bzw. einer dessen Signale auswertenden Auswer¬ teeinheit und Steuereinrichtung verbunden sein, so daß sie von dieser Steuereinrichtung im Bedarfsfalle betätigt bzw. gelöst wird. Die Absperreinrichtung kann beispielsweise im Bereich der Medizin-Technik aus Sicherheitsgründen erforder¬ lich sein, falls es beim Auftreten gewisser Druckverhält¬ nisse beispielsweise erforderlich ist, die Leitung 5 abzu¬ sperren, weil diese eine Infusionsleitung o.a. darstellt.The device 1 according to the invention can also be provided with a shut-off device, not shown in FIG. 1, which completely blocks the line 5 if necessary. The shut-off device 5 can preferably be connected to the pressure sensor 2 or to an evaluation unit and control device evaluating its signals, so that it is actuated or released by this control device when necessary. The shut-off device may be necessary for safety reasons, for example in the field of medical technology, if it is necessary, for example, to shut off line 5 when certain pressure conditions occur, because this line is an infusion line or the like. represents.
Um die Verformung der Leitung bzw. des Containers 5 bei der Innendruckbestimmung zu berücksichtigen, ist die erfindungs¬ gemäße Vorrichtung 1 ferner mit einer nicht näher darge¬ stellten Erkennungseinrichtung versehen, deren Funktion sich jedoch aus der Darstellung der Fig. 2 ergibt. In Fig. 1 sind beispielhaft drei Basisdruck-Kennlinien B , B und B dar- 1 2 3 gestellt. Diese Basisdruck-Kennlinien 1 symbolisieren unter¬ schiedliche Leitungstypen, deren Charakteristiken vor allem von den verwendeten Materialien und den Abmessungen abhän¬ gen. Die Basisdruck-Kennlinien B bis B werden von der Er- y 1 3 kennungseinrichtung der erfindungsgemäßen Vorrichtung 1 durch Bestimmung eines Anfangsgradienten G ermittelt. DieseIn order to take into account the deformation of the line or the container 5 when determining the internal pressure, the device 1 according to the invention is further provided with a detection device (not shown in detail), the function of which, however, results from the illustration in FIG. 2. 1 are three basic pressure characteristic curves B, B and B are shown by way of example. This base pressure characteristics 1 symbolize unter¬ schiedliche conductivity types, gene whose characteristics especially on the materials used and abhän¬ dimensions. The base pressure curves B to B y of the ER- 1 3 of the device 1 according to the invention detection device by determining an initial gradient G determined. This
A Ermittlung kann beispielsweise durch ein mathematisches Mo¬ dell erfolgen, auf dessen Basis die Erkennungseinrichtung nach der Bestimmung des Anfangsgradienten G den Kennlinien-A can be determined, for example, by means of a mathematical model, on the basis of which the detection device, after determining the initial gradient G,
A verlauf bestimmen kann. Da somit die Ausdehnungscharakte¬ ristiken sowie die Restelastizität der verformten Leitungen bestimmbar ist, kann die Innendruckmessung ohne Beeinflus¬ sung durch die Verformung vorgenommen werden. In Fig. 1 sind beispielhaft zur Verdeutlichung der Innendruckmessung einige Druckstöße dargestellt, die als Auslenkungen auf den Basis¬ druck-Kennlinien B bis B verdeutlicht sind.A course can determine. Since the expansion characteristics and the residual elasticity of the deformed lines can thus be determined, the internal pressure measurement can be carried out without being influenced by the deformation. In Fig. 1 some pressure surges are shown as an example to clarify the internal pressure measurement, which are illustrated as deflections on the basis pressure characteristic curves B to B.
1 31 3
Grundsätzlich sind bei dieser Basisdruck-Erkennung zwei Mög¬ lichkeiten gegeben. Im einen Falle kann die Erkennungsein¬ richtung mit einem Speicher versehen sein, der mit experi¬ mentell ermittelten Kennlinien einer Vielzahl von unter¬ schiedlichen Leitungen, Schläuchen oder Containern geladen ist, so daß durch einen Vergleich zwischen aufgenommener geometrischer Funktion und gespeicherter Kennlinie ermittelt werden kann, um welchen Schlauchtyp es sich handelt.Basically, there are two possibilities with this basic pressure detection. In one case, the detection device can be provided with a memory which is loaded with experimentally determined characteristic curves of a large number of different lines, hoses or containers, so that a comparison can be made between the recorded geometric function and the stored characteristic curve what type of hose it is.
Bei einem weiteren Modell ist es möglich, nur durch Bestim¬ mung des Anfangsgradienten die Kennlinie zu extrapolieren, was den Vorteil mit sich bringt, daß eine derartige Erken¬ nungseinrichtung unabhängig vom Schlauchtyp universell an¬ wendbar ist.In another model, it is possible to extrapolate the characteristic curve only by determining the initial gradient, which has the advantage that such a detection device can be used universally regardless of the hose type.
Die Erfindung ist nicht auf die zuvor beschriebenen Auε- führungformen beschränkt. Besonders bevorzugte Ausführungs- formen der erfindungsgemäßen Vorrichtung sind nachfolgend unter den Punkten 1 bis 14 zusammengefaßt:The invention is not restricted to the previously described embodiments. Particularly preferred execution Forms of the device according to the invention are summarized below under points 1 to 14:
1. Vorrichtung (1) zur Erkennung der Innendruckverhältnisse in flexiblen Leitungen, vorzugsweise schlauch- oder kis- senförmige flexiblen Leitungen oder Containern der Me¬ dizin-Technik,1. Device (1) for detecting the internal pressure conditions in flexible lines, preferably hose-shaped or pillow-shaped flexible lines or containers of medical technology,
- mit zumindest einem Drucksensor (2); und- With at least one pressure sensor (2); and
mit zumindest einer Übertragungseinrichtung (4) zur wirkungsmäßigen Kopplung der Leitung (5) und des Drucksensors (2), .wobei die Übertragungseinrichtung (4) eine unbewegliche und eine bewegliche Platte (6 bzw. 7) aufweist, zwischen denen die Leitung (5) unter Vorspannung angeordnet ist, wobei die bewegliche Platte (7) die Kopplung mit dem Drucksensor (2) bewirkt,with at least one transmission device (4) for the effective coupling of the line (5) and the pressure sensor (2), the transmission device (4) having an immovable and a movable plate (6 or 7) between which the line (5) is arranged under prestress, the movable plate (7) effecting the coupling to the pressure sensor (2),
bei derin the
- eine Erkennungseinrichtung vorgesehen ist, die den Leitungstyp durch Ermittlung der Rückstellkraft in der Übergangszeit vom elastischen Zustand in den plastischen Zustand bestimmt.- A detection device is provided which determines the type of line by determining the restoring force in the transition period from the elastic state to the plastic state.
2. Vorrichtung gemäß Punkt 1, bei der die Leitung (5) in vorgespanntem Zustand zwei im wesentlichen parallel lie¬ gende Wandabschnitte (12,13) aufweist.2. Device according to item 1, in which the line (5) has two essentially parallel wall sections (12, 13) in the pretensioned state.
3. Vorrichtung gemäß Punkt 2, bei der die Auslenkung der beweglichen Platte (7) in einer Richtung im wesentlichen senkrecht zum Wandabschnitt (13), an dem die bewegliche Platte (7) anliegt, erfolgt. 4. Vorrichtung gemäß einem der Punkte 1 - 3 , bei der die bewegliche Platte (7) mit einem Stößel (8) versehen ist, der auf der der Leitung (5) abgewandten Plattenseite der beweglichen Platte (7) angeordnet ist.3. Device according to item 2, in which the deflection of the movable plate (7) takes place in a direction substantially perpendicular to the wall section (13) against which the movable plate (7) rests. 4. Device according to one of items 1-3, in which the movable plate (7) is provided with a plunger (8) which is arranged on the plate side of the movable plate (7) facing away from the line (5).
5. Vorrichtung gemäß Punkt 4, bei der der Stößel (8) an seinem freien Ende ein konvexes Anlageteil (9) aufweist, das am Drucksensor (2) anliegt.5. The device according to item 4, in which the plunger (8) has at its free end a convex contact part (9) which bears against the pressure sensor (2).
6. Vorrichtung gemäß Punkt 4 oder 5, bei der der Stößel (8) reibungsarm geführt ist.6. Device according to item 4 or 5, in which the plunger (8) is guided with low friction.
7. Vorrichtung gemäß einem der Punkte 1 - 6, bei der die bewegliche Platte (7) und der Stößel (8) ein niedriges Gewicht im Vergleich zu den auftretenden Auslenkungs¬ kräften haben.7. Device according to one of the items 1-6, in which the movable plate (7) and the plunger (8) have a low weight in comparison to the deflection forces that occur.
8. Vorrichtung gemäß einem der Punkte 1 - 7 , bei der die feste Platte (6) Teil eines auf- und zuschließbaren Ge¬ häusedeckels ist.8. Device according to one of items 1-7, in which the fixed plate (6) is part of a lockable and closable housing cover.
9. Vorrichtung gemäß einem der Punkte 4 - 8 , bei der zur möglichst reibungsarmen Führung der beweglichen Platte (7) der Stößel (8) in einer Lagerung (11) geführt ist.9. Device according to one of the items 4-8, in which the plunger (8) is guided in a bearing (11) in order to guide the movable plate (7) with as little friction as possible.
10. Vorrichtung gemäß einem der Punkte 1 - 9, bei der durch eine Absperreinrichtung, die die Leitung (5) im Bedarfs¬ fall sperrt.10. Device according to one of the items 1-9, in which by a shut-off device which blocks the line (5) in the event of need.
11. Vorrichtung gemäß Punkt 10, bei der die Absperreinrich¬ tung in Abhängigkeit vom gemessenen Druck betätigbar ist.11. The device according to item 10, in which the shut-off device can be actuated as a function of the measured pressure.
12. Vorrichtung gemäß Punkt 1, bei der die Erkennung durch12. Device according to item 1, in which the detection by
Bestimmung eines Anfangsdruckgradienten (G ) pro Zeit-Determination of an initial pressure gradient (G) per time
A einheit erfolgt. 13. Vorrichtung gemäß Punkt 1 oder 2, bei der zur Erkennung eine Vergleichereinrichtung zum Vergleich zwischen dem ermittelten Druckverlauf und zuvor in einer Speicherein¬ richtung eingegebenen experimentell bestimmten Druckver¬ läufen unterschiedlicher Leitungstypen ausgeführt wird.A unit is done. 13. Device according to item 1 or 2, in which, for recognition, a comparator device is carried out for comparison between the determined pressure curve and experimentally determined pressure curves of different line types previously entered in a memory device.
1 . Vorrichtung gemäß Punkt 1 oder 2, bei der zur Erkennung aus dem Anfangsgradienten (G ) der Druckverlauf errech¬ net wird. 1 . Device according to item 1 or 2, in which the pressure curve is calculated for recognition from the initial gradient (G).

Claims

_ -Patentansprüche _ -Patent claims
1. Vorrichtung (1) zur Erkennung der Innendruckverhältnisse in flexiblen Leitungen, vorzugsweise schlauch- oder kis- senförmige flexiblen Leitungen oder Containern der Me¬ dizin-Technik,1. Device (1) for detecting the internal pressure conditions in flexible lines, preferably hose-shaped or pillow-shaped flexible lines or containers of medical technology,
- mit zumindest einem Drucksensor (2); und- With at least one pressure sensor (2); and
- mit zumindest einer Übertragungseinrichtung (4) zur wirkungsmäßigen Kopplung der Leitung (5) und des Drucksensors ( 2 ) , wobei die Übertragungseinrichtung (4) eine unbewegliche und eine bewegliche Platte (6 bzw. 7) aufweist, zwischen denen die Leitung (5) unter Vorspannung angeordnet ist, wobei die bewegliche Platte (7) die Kopplung mit dem Drucksensor (2) bewirkt,- With at least one transmission device (4) for the effective coupling of the line (5) and the pressure sensor (2), the transmission device (4) having an immovable and a movable plate (6 or 7), between which the line (5) is arranged under prestress, the movable plate (7) effecting the coupling to the pressure sensor (2),
gekennzeichnet,featured,
- durch eine Erkennungseinrichtung, die den Leitungstyp durch Ermittlung der Rückstellkraft in der Übergangs¬ zeit vom elastischen Zustand in den plastischen Zustand bestimmt.by a detection device which determines the type of line by determining the restoring force in the transition time from the elastic state to the plastic state.
2. Vorrichtung nach Anspruch 1, dadurch gekennzeichnet, daß der Stößel (8) reibungsarm geführt ist.2. Device according to claim 1, characterized in that the plunger (8) is guided with low friction.
3. Vorrichtung nach einem der Ansprüche 1 oder 2, dadurch gekennzeichne , daß die bewegliche Platte (7) und der Stößel (8) ein niedriges Gewicht im Vergleich zu den auftretenden Auslenkungskräften haben. 3. Device according to one of claims 1 or 2, characterized in that the movable plate (7) and the plunger (8) have a low weight compared to the deflection forces occurring.
4. Vorrichtung nach einem der Ansprüche 1 - 3, dadurch ge- kenzeichnet, daß die feste Platte (6) Teil eines auf- und zuschließbaren Gehäusedeckels ist.4. Device according to one of claims 1-3, characterized in that the fixed plate (6) is part of a lockable housing cover.
5. Vorrichtung nach einem der Ansprüche 1 - 4, dadurch ge¬ kennzeichnet, daß zur möglichst reibungsarmen Führung der beweglichen Platte (7) der Stößel (8) in einer Lage¬ rung (11) geführt ist.5. Device according to one of claims 1-4, characterized ge indicates that the guide (8) is guided in a position (tion) (11) in order to guide the movable plate (7) with as little friction as possible.
6. Vorrichtung nach einem der Ansprüche 1 - 5, gekennzeich¬ net durch eine Absperreinrichtung, die die Leitung (5) im Bedarfsfall sperrt.6. Device according to one of claims 1-5, gekennzeich¬ net by a shut-off device that blocks the line (5) if necessary.
7. Vorrichtung nach Anspruch 6, dadurch gekennzeichnet, daß die Absperreinrichtung in Abhängigkeit vom gemessenen Druck betätigbar ist.7. The device according to claim 6, characterized in that the shut-off device can be actuated as a function of the measured pressure.
8. Vorrichtung nach Anspruch 1, dadurch gekennzeichnet, daß die Erkennung durch Bestimmung eines Anfangsdruck¬ gradienten (G ) pro Zeiteinheit erfolgt.8. The device according to claim 1, characterized in that the detection is carried out by determining an initial pressure gradient (G) per unit time.
9. Vorrichtung nach einem der Ansprüche 1 - 8 , dadurch gekennzeichnet, daß zur Erkennung eine Vergleicherein¬ richtung zum Vergleich zwischen dem ermittelten Druck¬ verlauf und zuvor in einer Speichereinrichtung einge¬ gebenen experimentell bestimmten Druckverläufen unter¬ schiedlicher Leitungstypen ausgeführt wird.9. Device according to one of claims 1-8, characterized in that for the detection a Comparator device for comparison between the determined pressure curve and previously entered in a memory device experimentally determined pressure curves of different line types is carried out.
10. Vorrichtung nach einem der Ansprüche 1 - 8, dadurch gekennzeichnet, daß zur Erkennung aus dem Anfangs¬ gradienten (G ) der Druckverlauf errechnet wird. A 10. Device according to one of claims 1-8, characterized in that the pressure curve is calculated for detection from the initial gradient (G). A
PCT/EP1991/000761 1989-05-30 1991-04-19 Device for detecting inner pressure conditions in flexible ducts WO1991016609A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1019910701705A KR920701861A (en) 1989-05-30 1990-05-11 Ferroelectric liquid crystal display

Applications Claiming Priority (2)

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DEP4013403.2 1990-04-26
DE4013403A DE4013403C2 (en) 1990-04-26 1990-04-26 Device for detecting the internal pressure conditions in flexible lines

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Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1996003168A1 (en) * 1994-07-27 1996-02-08 Sims Deltec, Inc. Occlusion detection system for an infusion pump
US6077055A (en) * 1998-12-03 2000-06-20 Sims Deltec, Inc. Pump system including cassette sensor and occlusion sensor
EP1269145A1 (en) * 2000-02-28 2003-01-02 ALARIS Medical Systems, Inc. Force sensor assembly for an infusion pump
WO2012006656A1 (en) * 2010-07-12 2012-01-19 Custon Fluid Power Pty Ltd Pressure detection device
WO2013115852A1 (en) * 2012-02-01 2013-08-08 Baxter Healthcare S.A. Pressure sensing assembly for an infusion pump
US8858526B2 (en) 2006-08-03 2014-10-14 Smiths Medical Asd, Inc. Interface for medical infusion pump
US8954336B2 (en) 2004-02-23 2015-02-10 Smiths Medical Asd, Inc. Server for medical device
US8952794B2 (en) 2006-08-03 2015-02-10 Smiths Medical Asd, Inc. Interface for medical infusion pump
US8965707B2 (en) 2006-08-03 2015-02-24 Smiths Medical Asd, Inc. Interface for medical infusion pump
EP2603257A4 (en) * 2010-08-11 2017-11-15 Zevex, Inc. Pressure sensor and method of use
US10682460B2 (en) 2013-01-28 2020-06-16 Smiths Medical Asd, Inc. Medication safety devices and methods
US10726100B2 (en) 2008-05-02 2020-07-28 Tandem Diabetes Care, Inc. Display for pump

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
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GB2417052B (en) * 2004-08-12 2009-12-23 Single Use Surgical Ltd Pressure monitor for peristaltic pumps
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JP5594541B2 (en) * 2012-02-09 2014-09-24 Ｓｍｃ株式会社 Pressure detector
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DE102019102432A1 (en) * 2019-01-31 2020-08-06 Technische Universität Dresden Peristaltic pump

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4174637A (en) * 1978-10-19 1979-11-20 International Business Machines Corporation Pressure monitoring system
WO1984004685A1 (en) * 1983-05-23 1984-12-06 Baxter Travenol Lab Differential occlusion sensing method and apparatus
DE8520375U1 (en) * 1984-08-07 1985-10-31 Hospal Ag, Basel Peristaltic pump with a device for measuring pressure
EP0335385A2 (en) * 1988-03-30 1989-10-04 Nikkiso Co., Ltd. Method of and apparatus for detecting an occlusion of liquid transfusion tube
US4882575A (en) * 1987-01-28 1989-11-21 Sharp Kabushiki Kaisha Monitor for blocked condition in tube for fluid infusion pump
DE3838689C1 (en) * 1988-11-15 1990-06-28 Fresenius Ag, 6380 Bad Homburg, De Method for the continuous measurement of the pressure in a flexible fluid line for medical purposes, as well as a device for carrying out the method

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3376750A (en) * 1965-09-29 1968-04-09 R A Ekstrom Co Slack diaphragm fluid gauge
US3418853A (en) * 1966-01-10 1968-12-31 Statham Instrument Inc Blood pressure transducer
CA1081501A (en) * 1977-11-10 1980-07-15 Ronald Price Diesel fuel pipe transducer
GB2072349B (en) * 1980-03-18 1984-02-15 Gaeltec Ltd Conditioning pressure transducer outputs

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4174637A (en) * 1978-10-19 1979-11-20 International Business Machines Corporation Pressure monitoring system
WO1984004685A1 (en) * 1983-05-23 1984-12-06 Baxter Travenol Lab Differential occlusion sensing method and apparatus
DE8520375U1 (en) * 1984-08-07 1985-10-31 Hospal Ag, Basel Peristaltic pump with a device for measuring pressure
US4882575A (en) * 1987-01-28 1989-11-21 Sharp Kabushiki Kaisha Monitor for blocked condition in tube for fluid infusion pump
EP0335385A2 (en) * 1988-03-30 1989-10-04 Nikkiso Co., Ltd. Method of and apparatus for detecting an occlusion of liquid transfusion tube
DE3838689C1 (en) * 1988-11-15 1990-06-28 Fresenius Ag, 6380 Bad Homburg, De Method for the continuous measurement of the pressure in a flexible fluid line for medical purposes, as well as a device for carrying out the method

Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5695473A (en) * 1994-07-27 1997-12-09 Sims Deltec, Inc. Occlusion detection system for an infusion pump
US5935106A (en) * 1994-07-27 1999-08-10 Sims Deltec, Inc. Occlusion detection system for an infusion pump
WO1996003168A1 (en) * 1994-07-27 1996-02-08 Sims Deltec, Inc. Occlusion detection system for an infusion pump
US6077055A (en) * 1998-12-03 2000-06-20 Sims Deltec, Inc. Pump system including cassette sensor and occlusion sensor
EP1269145A1 (en) * 2000-02-28 2003-01-02 ALARIS Medical Systems, Inc. Force sensor assembly for an infusion pump
EP1269145A4 (en) * 2000-02-28 2008-03-12 Cardinal Health 303 Inc Force sensor assembly for an infusion pump
US8954336B2 (en) 2004-02-23 2015-02-10 Smiths Medical Asd, Inc. Server for medical device
US10437963B2 (en) 2006-08-03 2019-10-08 Smiths Medical Asd, Inc. Interface for medical infusion pump
US9740829B2 (en) 2006-08-03 2017-08-22 Smiths Medical Asd, Inc. Interface for medical infusion pump
US8858526B2 (en) 2006-08-03 2014-10-14 Smiths Medical Asd, Inc. Interface for medical infusion pump
US10255408B2 (en) 2006-08-03 2019-04-09 Smiths Medical Asd, Inc. Interface for medical infusion pump
US8952794B2 (en) 2006-08-03 2015-02-10 Smiths Medical Asd, Inc. Interface for medical infusion pump
US8965707B2 (en) 2006-08-03 2015-02-24 Smiths Medical Asd, Inc. Interface for medical infusion pump
US10726100B2 (en) 2008-05-02 2020-07-28 Tandem Diabetes Care, Inc. Display for pump
US11488549B2 (en) 2008-05-02 2022-11-01 Tandem Diabetes Care, Inc. Display for pump
US11580918B2 (en) 2008-05-02 2023-02-14 Tandem Diabetes Care, Inc. Display for pump
US9574952B2 (en) 2010-07-12 2017-02-21 Custom Fluid Power Pty Ltd. Pressure detection device
WO2012006656A1 (en) * 2010-07-12 2012-01-19 Custon Fluid Power Pty Ltd Pressure detection device
EP2603257A4 (en) * 2010-08-11 2017-11-15 Zevex, Inc. Pressure sensor and method of use
GB2514068B (en) * 2012-02-01 2018-08-29 Baxter Healthcare Sa Pressure sensing assembly for an infusion pump
WO2013115852A1 (en) * 2012-02-01 2013-08-08 Baxter Healthcare S.A. Pressure sensing assembly for an infusion pump
GB2514068A (en) * 2012-02-01 2014-11-12 Baxter Healthcare Sa Pressure sensing assembly for an infusion pump
US10682460B2 (en) 2013-01-28 2020-06-16 Smiths Medical Asd, Inc. Medication safety devices and methods
US10881784B2 (en) 2013-01-28 2021-01-05 Smiths Medical Asd, Inc. Medication safety devices and methods

Also Published As

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DE4013403A1 (en) 1991-11-07
DE4013403C2 (en) 1994-06-30

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