JPS5827560A - Medical pouring apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (1) Technical field This invention optically detects the drip status inside the drip tube and converts it into the magnitude of an electrical signal, and then divides the drip status into three types: no drip, no drip, and continuous flow. The present invention relates to a medical injection device that can monitor and/or control the amount of infusion by making a distinction.

(2) Background Art It is often necessary to deliver therapeutic solutions intravenously to a patient, and it is always important in performing this procedure that the rate of delivery of the fluid is known and controllable. . Particularly when a substance with a physiological effect is administered, it is very dangerous to increase the rate of administration, and the rate of administration must be controllable to a predetermined rate.

Therefore, as shown in FIG. 1, the medical injection device includes an injection bottle 1, an injection tube 3 having a drip tube 2 connected to the injection bottle 1,
A light emitter 4 and a photoreceptor 5 that detect the state of the drip and output it as an electric signal are arranged so as to intersect with the falling path of the drip in the drip tube 2 and face each other, and a drip valve 6 or 5 that opens and closes the injection tube 3 Note: The pump 7, which is a set of rollers or a set of fingers, is used to squeeze the inlet tube 3, and the electrical signal output from the photoreceptor 5 is processed to output a drip amount display signal to the drip amount display 8, and the drip valve 6 or pump 7 is activated. It is equipped with a drip status monitoring circuit 9 that controls the injection speed to the patient to be constant and the drip amount not to exceed a predetermined value, and a mask plate 10 having a slit just in front of the photoreceptor 5.

According to the medical injection device equipped with the drip valve 6,
The drip speed becomes a preselected flow rate under the action of gravity, and when the drip amount exceeds a predetermined value, the drip status monitoring circuit 9 causes the drip valve 6 to slightly throttle the injection tube 3. Further, the medical infusion device including the pump 7 has a pump 7 whose drip speed and drip amount are controlled by the drip status monitoring circuit 9.
is determined by the rotation of

However, in any of the above structures of the injection device,
Slit 1 of mask plate 10 provided immediately in front of photoreceptor 5
1 is a horizontally long rectangle as shown in Figure 2, and therefore the light intensity changes without dripping, with dripping, and continuous flow are shown in Figure 3 (a), (b), and (C), respectively. is not obtained sufficiently, and the output electrical signal of the photoreceptor 5 is
The values shown correspond to Figures (a), (b), and (C), respectively, and since there is almost no difference between the cases with dripping and the case with continuous flow, it is impossible to distinguish between the two. However, it is possible to do this by using a complicated method such as measuring the interval between drops and performing logical processing.

The drip state monitoring circuit 9 in FIG. 1 also includes an amplifier 12, a comparator 13, and a resistor 14 for setting the threshold value of the comparator 13, as specifically shown in FIG.
, a counter 15 , and a control circuit 16 . According to this configuration, if the photoreceptor 5 detects changes in the amount of light received by dividing them into no dripping, dripping, and continuous flow, it can detect the magnitude of voltage or current. Even if it could be output as an electrical signal, it is not configured to be able to read the difference between dripping and continuous flow. Therefore, in the case of continuous flow, comparator 13 and counter 1
5. The control circuit 16 cannot respond accurately, and the rate and volume of infusion into the patient become uncontrollable, putting lives at great risk.

Based on the above, the issues that need to be solved with conventional medical infusion devices are: One is the sensor that detects the state of drip in the drip tube 2 to reliably and accurately distinguish between no drip, drip, and continuous flow. The other is to improve the drip status monitoring circuit so that it can obtain a practical electrical signal that can be used as a drip status monitor. Reliably and accurately determine whether
The object of the present invention is to improve the ability to output control signals to the drip amount indicator 8 and the drip valve 6 or the pump 7 of a rotary set or a finger set.

(3) Disclosure of the Invention This invention maintains the sensor for detecting the state of dripping, which consists of a light emitter and a photoreceptor, as in the past in order to avoid high costs, and the amount of light received by the photoreceptor is determined by whether there is no dripping or if there is dripping. By providing an improved mask plate with a relative ratio that is sufficiently compatible with continuous flow and can be discriminated, a sensor with substantially improved detection capability is obtained, and the cost of conventional drip status monitoring circuitry is eliminated. A medical injection device that maintains a simple circuit configuration by adding to the conventional basic configuration without any particular changes, and that is capable of reliably and accurately determining electrical signals output from sensors and outputting control signals. The primary purpose is to provide the following.

According to the present invention, the purpose of this is to provide a drip status detector that is attached to a drip tube and detects the drip status, converts it into an electrical signal, and outputs it, and monitors the drip status by processing the output signal of this detector. and/or a drip status monitoring circuit for controlling the drip status detector, wherein the drip status detector includes a light emitting body and a light receiving body that face each other and intersect the optical axis in the falling path of the drip in the drip barrel;
In a medical injection device comprising a mask plate having a slit provided immediately in front of the photoreceptor, the slit of the mask plate is sized so that a vertically elongated amount of light that is longer than the vertical dimension of at least one intravenous drop is incident on the photoreceptor. , On the other hand, the above-mentioned drip status monitoring circuit is 2. A medical infusion device characterized by having a discrimination circuit that sets two threshold values and discriminates the output electrical signal obtained by the infusion state detector into whether there is no dripping, there is dripping, or continuous flow depending on the magnitude of the electric signal. achieved by.

In addition to the above-mentioned purpose, this invention also makes it possible to effectively use the king's drip condition of no drip, with drip, and continuous flow even when the drip tube is set at an angle and the drip falls off the center of the tube and falls due to gravity. A second object is to provide a medical injection device equipped with a sensor capable of discrimination and detection.

According to this invention, this second purpose cannot be achieved if the slit of the mask plate is made into a size such that an amount of light that is longer than the vertical dimension of at least one infusion is incident on the photoreceptor, that is, the slit is made into a required vertical rectangle. Since this is not a good idea, we cut the slit horizontal part corresponding to the horizontally long cutout of the slit on the mask plate, the slit vertical part corresponding to the part cut upward from this slit horizontal part, and the intersection of these slit horizontal part and slit vertical part. The shape is made up of a part of the slit, which corresponds to a notch with a large rounded corner, preferably an approximately inverted T-shape or an abbreviated shape, and more preferably each slit is formed in a shape corresponding to the diameter of the infusion. This can be achieved by keeping the size ratio of the sides constant.

(4) Best form for implementing the idea' (4-
1) Structure As shown in FIG. 5, the embodiment of the medical infusion device of this invention includes an infusion tube 3 having an infusion barrel 2 in an infusion bottle (not shown).
is connected to the IV drip tube 2, and the drip status detection sensor that converts the drip status into an electrical signal and outputs it is attached to the drip tube 2.The drip status detection sensor is attached to the drip tube 2 and outputs the drip status by converting the drip status into an electric signal. It consists of a light emitting body 4, a photoreceptor 5 such as a phototransistor, and a mask plate 10 having a slit 11 provided just in front of the photoreceptor 5. Injection tube 3
It is equipped with a pump 7 having a set of loans or a set of fingers for squeezing the drip pulp 6 or the pump 7, which processes the output electric signal of the photoreceptor 5 and outputs a drip amount display signal to the drip amount display 8. The infusion status monitoring circuit 9A controls the infusion rate to the patient to be constant and the infusion σ to not exceed a predetermined value. F
The slit 11 of the mask plate 10 has a size such that an amount of light that is longer than the vertical dimension of at least one drip is incident on the photoreceptor 5, and a preferable size is that the slit 11
As shown in FIG. 6(b), the width W is approximately equal to the diameter d of one infusion, and the vertical width is 1.5 to 3 times the diameter d of one infusion. Also slit 1
The distance between the drip nozzle and the drip nozzle is larger than the diameter of the drip nozzle. The reason why the slit 11 is changed from the conventional horizontal slit to a vertical slit is to make it possible to not only distinguish between no dripping and dripping, but also to effectively distinguish between different drip conditions, such as dripping and continuous flow, without making any mistakes. This is to increase the ratio of

According to experiments, the drip state can be effectively determined without error by making the width W of the slit 11 approximately equal to the diameter d of the drip and making the vertical width 1.5 to 3 times the diameter d of the drip. The ratio of the amount of light received can be obtained. On the other hand, the drip status monitoring circuit 9A is similar to the conventional drip status monitoring circuit 9 shown in FIG.
In comparison, it has a discrimination circuit 17 that sets two threshold values and discriminates the output electric signal obtained from the photoreceptor 5 into whether there is no dripping, there is dripping, or continuous flow depending on the magnitude of the signal. are different. Two-horn comparator (e.g. comparator) 13A.

13B is connected in parallel to the output side of the amplifier 12, and different voltage values vA and VB are set as threshold values by resistors 14'A and 14B, respectively.

Then, NO is detected between one comparator 13A and the measuring device 15.
The T circuit 18 and the AND circuit 19 are connected in series, and the other comparator 13B is also connected to the input side of the AND circuit 19, and the comparator 13B is also connected to a NOR circuit in parallel with the AND circuit 19. Further, the input end on the NOR circuit is connected to one comparator 13A, and the output side is branch-connected to the alarm and the control circuit 16. The comparator 13A is configured to output an output signal of O or 1 when the output signal from the amplifier 12 is higher or lower than a preset threshold value vA. Furthermore, the counter 15 manually inputs the output signal from the AND circuit 19, counts the number of infusions per unit time, outputs a corresponding pulse signal, and resets the previous count. There is. Further, the control circuit 16 inputs the output signal of the counter 15, compares it with a reference value preset in advance so that it can be adjusted as desired, and controls the drip valve according to the deviation value so that the deviation value disappears. The drip valve 6 outputs a control signal for feedback controlling the drip valve 6 or the pump 7, and when the cumulative total of the output signals of the counter 15 reaches a limit value corresponding to the desired drip amount.
The control circuit 16 outputs a control signal to completely close the pump 7 or stop the pump 7, and when the control circuit 16 inputs the output signal on the NOR circuit, it ignores the output signal from the counter 15. , and output a control signal to completely close the drip valve 6 or stop the pump 7 in response to the output signal on the NOR circuit. The drip amount display 8 receives the output signal from the counter 15 and displays the number of drips per unit time, the drip amount, and/or the cumulative drip amount in a digital or analog format.

Figures 6 (a), (b), and (e) are the next diagrams illustrating the ratio of the amount of light received by the photoreceptor 5 that changes in a limited manner due to the slit 11 of the mask plate 10 and the drip that falls across the slit 11, respectively. Figure (a) shows that the light rays limited to the area It shows that the light rays are received by the photoreceptor 5, which is the area X2 obtained by subtracting the area X2 blocked by the drip from the area X1, and the figure (C) shows that the area X of the slit 11 in the state of continuous flow is This shows that the area is almost completely blocked by the continuous drip, and the amount of light received by the photoreceptor 5 is extremely small.

Figures 7(a), (b), and (C) are respectively shown in Figure 6(a).
(t)) This corresponds to (C) and shows the change in the output signal of the photoreceptor 5.

FIG. 8(a) shows an electrical signal processed by the drip status monitoring circuit 9A, and FIG. (b) shows the output signal of comparators 1 and 3 A, and this signal is output when the amount of light received is maximum because there is no dripping.
) shows the output signal of the comparator 13B, which is output when there is no dripping and when there is dripping, and (d) of the same figure shows the output signal of the NOT circuit 18, which signal is output when there is dripping and when there is continuous flow. Figure (e) shows the output signal of the AND circuit 19, which is output when there is a drop, and Figure (f) shows the output signal of the NOR circuit 20, which is output when there is a continuous flow. Output when .

(4-2) Operation Now, the amount to be infused at one time to the patient and the desired drip speed to be controlled must be set in the infusion status monitoring circuit 9A. This setting suffices by presetting two reference values in the control circuit 16. Among the two reference values, one is for setting the total amount of one infusion, and the other is for setting the infusion rate to a desired value depending on the type of infusion. In addition, especially when controlling the injection speed through the injection tube 3 by performing feedback control at a desired time interval of 30 seconds or 1 minute, the counter 15 may be configured to be preset so that the unit counting time can be adjusted. use something

In FIG. 5, the drip falling inside the drip barrel 2 is
intersects the optical axis of the photoreceptor 5, and the mask plate 10
Since the slots and slits 11 are formed to have the required length, the ratio of the amount of light received by the photoreceptor 5 changes as shown in FIGS. b) (C
), it outputs electrical signals corresponding to no dripping, dripping, and continuous flow, respectively.

Then, the output signal of the photoreceptor 5 is amplified by the amplifier 12,
The signal becomes as shown in FIG. 8(a), and then the two comparators 1
Input them in parallel to 3A and 13B respectively.

The comparator 13A outputs a signal of 1 as shown in FIG. 8(b) when there is no dripping, and the NOT circuit 18 outputs a signal of 1 when the output No. 9 of the comparator 13A is O, that is, when there is dripping and continuous flow. A signal of 1 is output for each. As shown in FIG. 8(C), the comparator 13B outputs an output when there is no drop exceeding the threshold value VB and when there is a drop, and the AND circuit 19 outputs the signal from the NOT circuit I8 and the signal from the comparator 13B. 8
As shown in Fig. 8(e), a signal of 1 is output when there is a drop, and when neither of the comparators 13A and 13B of the NOROR circuit is input, that is, as shown in Fig. 8(f). Output during continuous flow. Therefore, in this embodiment, two comparators 13A and 13B with different threshold values are used.
, NOT circuit 18, AND circuit ]9, and NOROR
Depending on the circuit combination, the drip status of no drip, drip, and continuous flow can be effectively determined without malfunction. Then, the counter 15 counts the number of drips per unit time, for example, per minute, and outputs a corresponding signal, and the drip amount display 8 displays the drip amount per unit time and/or the cumulative drip amount. is displayed digitally or analogously. In addition, the control circuit 16 always inputs the pulse signal from the counter 15 and compares it with a reference value preset in itself, and if there is a deviation, outputs a feedback signal according to the deviation so that the deviation disappears. In addition, when the cumulative total of pulse signals from the counter 15 reaches a preset limit value or when the output signal of the NOROR circuit group is input, the control circuit 16 receives this and continues to output the injection tube closing signal. .

Therefore, when the drip valve 6 or the pump 7, which is an automatic dripper, receives a feedback signal from the control circuit 16 every unit time, the valve opening degree or the pump rotation speed is adjusted respectively, and the infusion through the injection tube 3 is adjusted. The volume is controlled at a predetermined speed, and when the injection tube closing signal is input from the control circuit 16, that is, when the drip volume reaches a limit value or when the flow is continuous, the valve is completely closed or the pump rotation is stopped. to make the infusion volume through the injection tube 3 zero. At this time, the intravenous drip inside the drip tube 2 is stopped due to the increase in pressure within the tube.

Further, the alarm device 21 issues an alarm when receiving the output signal from the NOR circuit.

Furthermore, when the automatic drainage system closes due to continuous drip flow and an alarm sounds, the doctor or nurse should distinguish this from the cumulative drip volume reaching the limit value and the alarm sounding. This is determined by monitoring the drip amount indicator 8 and drip tube 2.

(5) Modification (5-1) Modification regarding the slit 11 of the mask plate 10 When the injection bottle is attached to a stand or the like that is far from the patient,
The drip tube may be set at an angle. In such a case, continuous flow cannot be detected because the continuous flow does not intersect with the light ray passing through the vertically long rectangular slit bent at the continuous flow blade changer. For this reason, it is necessary to ensure the safety of the device by detecting continuous flow even if the drip barrel is tilted. FIG. 9 shows a front view of the essential parts of an injection device that ensures such safety. To ensure such safety, a means is provided to notify a doctor or nurse that the IV tube is tilted, and a means is provided to notify the doctor or nurse that the IV tube is tilted. A solution could be modification, but this would increase the cost of the device, so in this invention, the shape of the slit is devised so that continuous flow can be effectively detected even if the drip tube is set at an angle. That is, as shown in FIG. 9, not only the vertical dimension of the slit 11 of the mask plate 10 but also the horizontal dimension are made 1.5 to 3 times the diameter of the drip, and the drip is continuous so that it bends under the action of gravity. The shape of the slit 11 is determined so that the light beam passing through the slit 11 is quickly cut off by the flow.

In FIG. 9, the shape of the slit 11 is approximately an inverted T-shape, but the shape is not limited to this.

FIG. 10 shows the slit 11 included in this invention.
Figure (a) shows a vertically long rectangular slit, the width W of the slit is approximately the same as the diameter of the drip, and the vertical width of the slit is approximately the same as the diameter of the drip. The ratio is 1.5 to 3 times, preferably 2 to 3 times in order to obtain a practically preferable light reception ratio, and the circle indicated by a dotted line with diameter dimension indicates the size of the effective light reception area of the photoreceptor.

As mentioned above, such a vertically long rectangle can detect the following drip conditions: no dripping, dripping, and continuous flow when the drip tube is set vertically correctly, and with dripping when the drip tube is set at an angle. and cannot detect continuous flow. Same figure (b).

(C), (d), and k> respectively show various shapes devised to enable detection with practical changes in light intensity even if the drip tube is set at an angle. As shown in C), a horizontal slit portion 111 corresponding to a horizontally long cutout of the slit 11, a vertical slit portion 112 corresponding to a portion cut upward from the horizontal portion of the slit, and these horizontal portions and the slit. It is preferable that the corner where the vertical portions intersect is formed into a substantially inverted T-shape or an abbreviated-shape, which is a shape consisting of a slit corner portion 113 corresponding to a large rounded notch. When the slit 11 is shaped like an inverted T-shape, it can be used in an infusion device in which the drip tube can be set tilted in any direction, whereas when it is shaped like an abbreviated shape, the drip tube can only be set in one predetermined direction. Can be used in injection devices that are sometimes set at an angle.

Figures 10('b) and 10(c) show slit shapes that can detect the continuous flow of drips even when the drip barrel is set at an angle.

As can be seen from (d) and (e), it is necessary that the slit be edged in a curved line to correspond to the state in which the continuous flow bends due to the action of gravity. Figure 1 () (b), (e),
The bets placed in the slits shown in (d) and (e) are inserted to clarify the slit shape in comparison with the dimensions shown in IJ (a). The dimension L-W shown in FIG. 4B, that is, the vertical side of the vertical part of the slit, is 0.5 to 2 times the diameter of one drip.

In addition, in the case of the slit shapes shown in Figures (b) and (e), the width dimension is larger than that in Figures (d) and (e), respectively, so the distance between the drip nozzle and the slit shown in Figure 5 is This is effective when the distance is made large, but in the case of the slit shapes shown in FIGS.

(5-2) Modified example of the drip status monitoring circuit 9 The drip status monitoring circuit 9 has two threshold values, and the output electric signal obtained from the photoreceptor is outputted depending on the size of the output electric signal: no drip, drip, or continuous flow. It is sufficient that the configuration includes a discriminating circuit that discriminates between the three types, and is not limited to the case where the discriminating circuit 17 shown in FIG. 5 is included. For example, as shown in FIG. 11, a circuit may be used in which the input of the comparator 13B is inverted so that an output is output when the flow is continuous.

(6) Effects As explained above, the medical infusion device of the present invention has a photoelectric drip status detector attached to the drip barrel, and changes in the electrical signal obtained by the detector are calculated by the drip status monitoring circuit. For monitoring and/or controlling the drip volume and drip speed by processing and distinguishing between the following drip conditions: no dripping, dripping, and continuous flow, it is practical to change the slit from the conventional horizontally long rectangle to the required vertically long rectangle. In addition to obtaining a rate of change in the amount of light, the drip state monitoring circuit is also configured to include a discriminating circuit that discriminates among three types: no dripping, dripping, and continuous flow. Therefore, according to the medical infusion device of the present invention, the sensor for detecting the drip state is equipped with a light emitter and a photoreceptor, and the slit of the mask plate is simply improved. It has been possible to distinguish only the two types of drip status, but by adding continuous flow, it can be determined sufficiently and effectively as a practical light reception ratio, and the improvement cost is almost negligible. The circuit also has two threshold values and is simply attached to a conventional circuit with a relatively simple discriminating circuit that can distinguish the electrical signals obtained from the body into the light receiving body, which simplifies the circuit configuration. It is possible to reliably and accurately distinguish between no dripping, dripping, and continuous flow, and the drip status can be monitored and/or controlled using the drip amount display and automatic cleanser, and the desired purpose can be achieved. In addition, as an embodiment of the present invention, not only the vertical width but also the horizontal width of the slit of the mask plate is made 15 to 3 times larger than the diameter of the drip, and the corners of the horizontal part of the slit and the vertical part of the slit are cut out with large roundness. When the shape is approximately an inverted T-shape, an abbreviated shape, etc., the slit shape becomes a shape that can practically change the amount of light received in the relationship between the effective light-receiving area of the photoreceptor and the light-blocking area of the drip, and therefore Practical output electrical signals are obtained, there are no malfunctions, and three types of drips can be effectively distinguished: no drip, drip present, and continuous flow.Especially when the drip tube is set at an angle, the drip falls off the center of the tube and falls by gravity. Kano is an effective discrimination in this case.
As a result, high reliability and high safety of the device are maintained.

[Brief explanation of the drawing]

1 to 4 relate to a conventional example, and FIG. 1 is a conceptual diagram for explaining the overall configuration of a medical injection device, FIG. 2 is a structural perspective view and circuit diagram of main parts, and FIG. ), (b)
, (C) is a front view showing the relationship between the main parts of the mask plate and the dripping state, and FIG. 4(a). (b) and (c) are respectively shown in Figure 3 (a) and (
FIG. 6 is an output diagram showing the magnitude of the output electrical signal of the photoreceptor corresponding to e). 5 to 8 show embodiments of the present invention, and FIG. 5 corresponds to FIG. 2, and is a structural perspective view and circuit diagram of the main parts of the medical injection device, and FIG. 6(a)
, (b) and (e) are front views showing the relationship between the mask plate and the drip state, respectively, and Fig. 7 (a) and (b) (
e) are shown in Figures 6(a), (b), and (e), respectively.
Figure 8 (a), (b), (C), (d) showing the magnitude of the output electrical signal of the photoreceptor corresponding to
, (e) and (f) are output diagrams showing output signals of an amplifier, two comparators, a NOT circuit, an AND circuit, and a NOR circuit, respectively, in the circuit shown in FIG. Fig. 9 is a front view of the main part of a modified example of the present invention for explaining the improved slit shape of the mask plate so that continuous flow can be detected even if the drip tube is set at an angle, and Fig. 10 is a front view of the main part of this modification. FIG. 3 is a front view of a mask plate having various slit shapes included in the invention. FIG. 11 is a circuit diagram for determining the drip state according to a modification of the present invention. 2...Drip barrel, 3...Injection tube, 4...Light emitter, 5
...Photoreceptor, 9A...Drip status monitoring circuit, 1o...
Mask plate, 11...Slit, 111...Slit horizontal part, 112...Slit vertical part, 113...Slit code eleventh part, 17...Discrimination circuit. Patent applicant Terumo Corporation Figure 6 Figure 7

Claims (1)

[Scope of Claims] 1. A drip status detector that is attached to a drip tube to detect the drip status, convert it into an electrical signal, and output it, and monitor and/or control the drip status by processing the output signal of this detector. The drip status detector includes a light emitting body and a photoreceptor facing each other across the optical axis line in the falling path of the drip in the drip tube, and a mask plate having a slit provided just in front of the photoreceptor. In the medical infusion device, the slit of the mask plate has a size such that a vertical light amount longer than the five vertical dimensions of at least one infusion is incident on the photoreceptor, and the infusion status monitoring circuit has two threshold values. A medical injection device characterized by having a discrimination circuit for discriminating the output electric signal obtained from the photoreceptor into whether there is no dripping, there is dripping, or continuous flow depending on the size of the output electric signal obtained by the photoreceptor. 2 The slit in the mask plate has a horizontal part corresponding to a horizontally long notch, a vertical part of the slit corresponding to a part cut upward from the horizontal part of the slit, and a horizontal part of the slit and a slit. 2. The medical injection device according to claim 1, wherein the medical injection device has a shape consisting of a part of a slit corner corresponding to a portion where the corner where the vertical portion intersects is largely rounded. 3. The medical injection device according to claim 2, wherein the slit of the mask plate is formed in a substantially inverted T-shape. 4. The medical injection device according to claim 2, wherein the slit of the mask plate is formed in an abbreviated shape. 5 The vertical side of the horizontal part of the slit is approximately equal to the diameter of one infusion, and the horizontal side is 15 to 3 times the diameter, and the vertical part of the slit is approximately equal to the diameter of one infusion, and the vertical side is 05 times as large. The medical injection device according to any one of claims 2, 3, and 4, characterized in that the injection capacity is doubled.