JPH025093B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a dialysis machine using dialysis technology, such as a so-called artificial kidney, and to measuring the amount of dialysate flowing into the dialyzer and the amount of dialysate flowing out from a permeator. The present invention relates to an ultra-excess measurement mechanism that measures the difference between the amount of liquid and the so-called ultra-excess amount.

[Conventional technology]

FIG. 5 is a block diagram of a conventional ultraviolet amount measuring mechanism disclosed in Japanese Unexamined Patent Publication No. 48-61196. The dialysate is sent from the dialysate supply section 40 to about 2 to 5 dialysate tanks 1 through the valve SV-I.
The dialysate from the tank 1 is supplied to the dialyzer 5 through the heater 2, the bubble remover 3, and the liquid pressure control valve 4 in this order, and the dialysate flowing out from the dialyzer 5 is passed through the flow rate control valve 6 and the circulation pump 7. , the dialysate is returned to the dialysate tank 1 to form a circulation system, and the dialysate is being circulated. Further, if necessary, the dialysate is discarded by operating the valve SV-D, and a new dialysate is supplied from the dialysate supply section 40 to the dialysate tank 1. Blood is passed through the dialyzer 5 through the blood circuit 71, and water that passes through the dialysis membrane 10 in the dialyzer 5 and transfers from the blood to the dialysate increases the amount of dialysate, and the increased amount of fluid is The dialysate overflows from the outlet 8 in the dialysate tank 1, passes through a valve (three-way valve) SV-M, enters the ultraviolet amount measuring device 9, and the ultraviolet amount is measured.

When replacing the circulating dialysate, first move the valve SV-M from the ultra-excess meter 9 to the waste side.
Valve SV-D is kept open and valve SV-I is kept closed, and the dialysate in the dialysate tank 1 is discarded.
When the liquid level in the dialysate tank 1 falls to a predetermined level, valve SV-D is closed and valve SV-I is closed.
is opened and fresh dialysate is supplied to the dialysate tank 1. Thereafter, when the liquid level in the dialysate tank 1 reaches a level at which the dialysate overflows from the outlet 8 (overflow level), that is, a level higher than the outlet 8, the valve SV-I is closed. While this operation is being performed, the dialysate continues to circulate within the circulatory system. The time (usually 30 seconds to 2 minutes) from the time when the supply of dialysate to the dialysate tank 1 is finished, that is, from the time when the valve SV-I is closed until the liquid level in the dialysate tank 1 stabilizes. After the lapse of time, the valve SV-M is automatically switched from the waste side to the measuring device 9 side.

In this way, the dialysate is circulated, and in the dialyzer 5, through the dialysis membrane 10, water moves towards the dialysate together with the desired substances to be removed from the blood, and the volume of the dialysate increases, This increased amount of fluid overflows within the dialysate tank 1 and is led to the ultra-excess meter 9 through the outlet 8. This operation continues until the next dialysate disposal time. During this time, the ultraviolet amount measuring device 9
The amount of fluid introduced is the amount of water that transferred from the blood side to the dialysate side during the time when the valve SV-M was on the measuring device 9 side.

The time at which measurements are taken by the measuring device 9 is determined by the valve
This is within the time when SV-M is on the measuring instrument 9 side,
From the ratio of this time to the time when the valve SV-M is on the waste side and the amount measured by the measuring device 9, the total amount of ultraviolet amount during the entire dialysis time can be calculated.

[Problem that the invention seeks to solve]

In this conventional ultra-overload measuring mechanism, the capacity of the dialysate tank 1 is about 2 to 5, but when the tank has this capacity, its horizontal cross-sectional area is generally quite large. Since the surface tension of the dialysate in the dialysate tank 1 increases in proportion to the horizontal cross-sectional area of the tank, in this conventional device, the flow of dialysate overflowing from the dialysate tank 1 is affected by the surface tension. The disadvantage is that the flow is often intermittent.
For example, the flow of overflowing dialysate from the tank 1 having a cross-sectional area of about 300 cm ² is an intermittent flow, and the amount of outflow at one time is about 130 ml. Therefore, the time it takes for one overflow to occur or the time from one overflow to the next overflow is affected by surface tension, and it takes many tens of minutes, especially when the ultra-large excess amount is small. . For this reason, it is necessary to take a long time in the circulation mode in which the dialysate is circulated. There is a drawback that dialysis efficiency decreases when the time in circulation mode is prolonged.

In addition, the overflow liquid does not flow continuously and stably, and the dialysate level is affected by surface tension, so overflow does not always occur at the outlet 8 in Figure 5; Rather than being constant, overflow actually occurs at a position higher than the position of the outlet 8 in FIG.
Stop at the position. Therefore, compared to detecting the overflow level when the overflow level is always constant, detecting the overflow level in this case has the disadvantage that it is considerably more difficult and involves errors.

For these reasons, the conventional device shown in FIG. 5 could not accurately measure the ultraviolet amount.

The object of the invention is to eliminate the above-mentioned drawbacks in ultra-overmeter measuring mechanisms.

[Means for solving problems]

This invention includes an overflow tank connected to a dialysate tank through a communication pipe and having a smaller horizontal cross-sectional area than the dialysate tank, a measurement unit that accurately measures the dialysate overflowing from the overflow tank, and a circulation system for a dialysis machine. mode, drain mode (mode to discard dialysate from the dialysate tank) and fluid supply mode (mode to supply new dialysate to the dialysate tank), and also calculate the value measured by the above measurement unit in circulation mode. and a calculation control section that calculates the ultra-limit excess amount.

〔Example〕

Configuration of First Embodiment FIG. 1 is a block diagram showing an embodiment of the present invention. The same parts as in the conventional example shown in FIG. 5 are given the same reference numerals. The dialysate supply section 40 is a valve.
It is connected to the dialysate tank 1 via V ₁ . The outflow port of the dialysate tank 1 is connected to a circulation pump 7, a flow rate regulating valve 6, and, if necessary, a flow meter 25 in this order by a flow tube, and then connected to a dialysate input port of the dialyzer 5. The dialysate output port of the dialyzer 5 is connected to the switching means 2.
Connected to port 1 of 2. Port 3 of switching means 22 is connected to a flow line between said valve V ₁ and the input port of dialysate tank 1, optionally via heater 2. This constitutes a circulation path for the dialysate.

On the other hand, an overflow tank 27 having a smaller horizontal cross-sectional area than the dialysate tank 1 is connected to the dialysate tank 1 through a communication pipe 26, and an outlet 8a is provided in the overflow tank 27 above the communication pipe 26.
is provided, and its outlet 8a is connected to the measurement unit 28.
is connected with. This measuring unit 28 includes, for example, a measuring tank 29 supplied with liquid from an overflow tank 27, a full level sensor 30, and a measuring tank 29.
Consists of valve V ₄ for draining the liquid inside.
When the liquid level in the overflow tank 27 becomes higher than the outlet 8a, the liquid in the overflow tank 27 overflows from the outlet 8a, but the flow of the overflowing liquid is not intermittent but uniform. , the horizontal cross-sectional area of the overflow tank 27 is selected to be small.

The dialysate tank 1 is provided with a lower limit level sensor 23 and connected to a drain valve _V3 . The above-described valve V ₁ , switching means 22 (hereinafter referred to as valve V ₂ ), valves V ₃ and V ₄ , and circulation pump 7
and a lower limit level sensor 23, which controls the heater 2;
A calculation control section 24 is provided which receives a signal from the full level sensor 30 and calculates an ultra-limit excess amount.
When the valve V ₂ is switched to the port 2 side, the dialyzer 5 is connected to the drain pipe 72 .

Operation of the first embodiment The operation of the embodiment of FIG. 1 will be explained with reference to the operation flowchart of FIG. 2 and the mode-by-mode operation diagram showing detailed operations of FIG. 3.

First, at the time of startup, mode 1 (initial mode) is set in which the supply of dialysate to the dialysate tank 1 is started, and the dialysate from the dialysate supply unit 40 is opened (ON).
The dialysate is supplied to the dialysate tank ₁ through the valve V1. The other valves V ₂ to V ₄ , pump 7 and heater 2 are OFF. Pump 7 is in non-operating state OFF, operating state is ON, heater is operating state
ON, non-operating state is indicated as OFF. The above-mentioned valves V ₁ to _{V 4} , pump 7, and heater 2 are operated by the calculation control unit 2.
4. The capacity of the dialysate tank 1 is usually about 2 to 10. The level of the dialysate in the dialysate tank 1 reaches the position of the lower limit level sensor 23 provided in the tank, and the level sensor 23
When activated, the mode shifts to mode 2.

In mode 2, the level sensor 23 is connected to the control unit 24.
The detection signal is transmitted, and the control unit 24 controls the circulation pump 7.
turns on and issues a control signal so that heater 2 operates. At this point, the dialyzer 5 is supplied with dialysate. Since fresh dialysate is continuously supplied from the dialysate supply section 40, the level of the dialysate tank 1 gradually rises. This dialysate tank 1 has a communication pipe 26
The dialysate tank 1 is connected to the overflow tank 27 via the dialysate tank 1, and the rise in the liquid level in the dialysate tank 1 is transmitted to the rise in the liquid level in the overflow tank 27 with a slight delay. This overflow tank 27 has a small capacity of, for example, 100 to 200 c.c., and its horizontal cross-sectional area is also small, about 10 to 20 cm ² (when the height is 10 cm), but the cross-sectional area is too small to cause capillary action. Moreover, there is almost no influence of surface tension, and almost continuous overflow is possible. In addition, dialysate tank 1 and overflow tank 2
7 is open to the atmosphere. The occurrence of an overflow in the overflow tank 27 is detected by a measuring unit 28 that measures the overflowing liquid. The drain valve V ₄ of the measurement unit 28 is closed, and the overflow liquid from the overflow tank 27 is stored in the measurement tank 29 . Since the drain valve _V4 is closed, the level of the stored liquid gradually rises, and when the level sensor 30 attached to the measuring tank 29 detects that it is full, it issues a signal.
The mode will now shift to mode 3.

In mode 3, when the control unit 24 receives this full signal, it outputs a control signal so that the valve V ₁ is closed (OFF) and the drain valve V ₄ of the measuring tank 29 is turned ON. As mentioned earlier, the liquid level in the dialysate tank 1 rises slightly faster than the liquid level in the overflow tank 27, so even after turning off the valve V1, the communication pipe ₂₆ from the dialysate tank 1 cannot be connected. The dialysate flows into the overflow tank 27 via the overflow tank 27 .
The time it takes for the levels of the dialysate tank 1 and the overflow tank 27 to stabilize at the overflow level of the overflow tank 27 depends on the capacity of the dialysate tank 1 and the inner diameter of the communication pipe 26.
Usually, it is selected to be about 2 to 5 minutes, and is set in the advance calculation control section 24.

When the time for the liquid level to become stable has elapsed, the mode shifts to circulation mode 4. The control unit 24 closes the drain valve V ₄ of the measurement tank 29 where the dialysate is empty, sets the valve V ₂ to the state where port 1 is connected to the port 3 side (indicated by 1 → 3), and sets the limit Overdose measurement begins. When the measurement tank 29 reaches a full level and the level sensor 30 issues a full signal, circulation mode 5 is activated.
Move to.

In circulation mode 5, when the control unit 24 receives the full signal, it opens the drain valve V ₄ and closes the measuring tank 29.
is drained. The time t _d for which this valve V ₄ is open is determined by the calculation control unit 2 based on experimental data.
It is set to 4. Normally t _d is about 7 seconds.

In the circulation modes 4 and 5, the amount of water that moves from the blood side to the dialysate side in the dialyzer 5 is equal to the amount of fluid that overflows from the overflow tank 27, as explained in the prior art with reference to FIG. easily understood from

Circulation modes 4 and 5 are repeated several times, but the standard time that serves as a guideline for the overall operating time is determined in advance by the calculation control unit 24, and the entire operating time until the nth cycle of circulation mode 5 ends. When exceeds the above-mentioned standard time, the number of repetitions of the circulation mode is stopped at the above-mentioned n, and the mode shifts to drain mode 6.

In drain mode 6, the drain valve V ₃ connected to the dialysate tank 1 is activated by a signal from the control unit 24.
is open, and valve V ₂ connects port 1 side to port 2.
Switched to connect with the side. The drain line leading to the valve _V3 of the dialysate tank 1 has a diameter larger than the diameter of the input port of the dialysate tank 1, and the liquid level in the dialysate tank 1 gradually decreases. The liquid level in the overflow tank 27 similarly decreases. The liquid level of dialysate tank 1 is dialysate tank 1
When the level falls to the level of the lower limit level sensor 23, this level sensor 23 issues a detection signal and shifts to liquid supply mode 7.

In fluid supply mode 7, the drain valve V ₃ connected to the dialysate tank 1 and the drain valve V ₄ of the measuring tank are closed;
Valve _V1 is opened. In liquid supply mode 7,
The same operation as in liquid storage mode 2 is performed. The dialysate level supplied to the dialysate tank 1 rises, an overflow is detected, and the mode shifts to the post-supply mode 8.

The operation in liquid supply mode 8 is similar to that in liquid storage mode 3 described above.

Measurement of ultraviolet excess amount in the first embodiment The overflow liquid amount (corresponding to the ultraviolet amount) in circulation modes 4 and 5 is measured as follows.

The capacity of the measuring tank 29 (including the capacity in the piping up to the drain valve _V4 ) is Vml, the time from when the valve _V4 is closed until the full level is detected by the full level sensor 30 is t _fi minutes, Also, if the time during which the drain valve _V4 is open after detecting the full level is t _d minutes, the ultra-limit overflow rate in one measurement is V/
t _fi ml/min. Further, the ultraviolet amount measured in one measurement is V+(V/t _fi )×t _d =V(1+t _d /t _fi )ml.

These calculations are performed by the calculation control section 24 upon receiving the detection signal from the full level sensor 30 of the measuring tank 29, and the ultra-limit excess amount and the ultra-ultimate excess amount are displayed on the display section 31. The total ultraviolet amount UF _R in the circulation mode repeated n times is UF _R = _o 〓 ⁱ⁼¹ V (1 + t _d /t _fi ), which is similarly determined by the calculation control unit and displayed on the display unit 31. .

The time required for liquid drain mode 6 and liquid supply modes 7 and 8 is accurately measured by the calculation control unit 24,
Correction of the extreme excess amount in these two modes is performed as follows.

If the total time of circulation modes 4 and 5 repeated n times is t _R minutes, then t _R = _o 〓 ⁱ⁼¹ (t _fi + t _d ). Also, if the time in drain mode 6 is t _D minutes, and the total time in liquid supply modes 7 and 8 is t _P minutes, the average ultraviolet flow rate in circulation modes 4 and 5 is UF _R /t _R ml/min. Become. Therefore, the amount to be corrected in drain mode 6 is:
(UF _R /t _R ) × t _D ml, and the amount to be corrected in liquid supply modes 7 and 8 is (UF _R /t _R ) × t _P ml, and one cycle (circulation mode, drain mode, and liquid supply mode) The extreme excess amount in this mode is UF _R + (UF _R /t _R ) × t _D + (UF _R / t _R ) × t _p = UF _R {1 + (t _D + t _P ) / t _R }.

Now, as an important factor in determining the ultraviolet amount,
There is TMP (dialyzer membrane pressure). This TMP is (pressure of blood in dialyzer 5) - (pressure of dialysate in dialyzer 5), but in the case of this invention, what is relevant is:
Dialysate pressure only. If this TMP does not change in the circulation mode, liquid drain mode, and liquid supply mode, it is possible to accurately measure the ultraviolet amount with almost no errors, but in reality, the value will be different in each mode. However, in this invention, the dialysate tank 1 and the overflow tank 27 are open to the atmosphere, and there is almost no difference in dialysate pressure between the circulation mode and the fluid supply mode. To be precise, there is only a difference in the water levels of both tanks 1 and 27 between the circulation mode and the liquid supply mode, and the difference is extremely small, about 2 to 3 mmHg. However, in the drain mode, the dialysate in the dialysate tank 1 is drawn to the drain valve V ₃ , so that the dialysate pressure is e.g.
It decreases by about 30mmHg. The TMP therefore increases and the ultrafluid flow rate increases in this drain mode than in the circulation mode. However, the draining time usually only takes 2 to 3 minutes, and even if the difference in the ultra-overflow rate between the drain mode and the circulation mode is 5 ml/min, the amount of error is only about 10 to 15 ml.

In reality, if the difference between the measured ultraviolet amount and the amount of weight loss after 5 hours of dialysis is within ±200 g (converted), there will be no problem, and if the difference is within ±200 g (converted), there will be no problem. Assuming the cycle is 30 minutes, the amount of error in 5 hours in the above case is estimated to be 15
×2×5=within 150ml, weight equivalent to ±200g
It falls within the following range. By accurately setting the capacity of the measurement tank 29 for measuring the ultraviolet amount in the circulation mode, it is possible to make the measurement error in the circulation mode extremely small, and to reduce the error in the drainage mode. Even taking this into account, it is easy to keep it within ±200g.

Note that the measuring mechanism according to the present invention has a dialysate supply unit (patient monitoring device) 4 as shown in the example shown in FIG.
The present invention is applicable not only to the case where the present invention is installed as an adapter between the dialysis machine 0 and the dialyzer 5, but also to the case where it is incorporated into the dialysate supply unit 40 or a personal dialysis machine.

Second Embodiment FIG. 4 shows another embodiment of the present invention incorporating a microcomputer, with the same numbers assigned to those corresponding to those in FIG. 1. The operation-related diagrams in FIGS. 2 and 3 can be applied to this example as well.

In this example, each sequence of the circulation mode, liquid drain mode, and liquid supply mode and the device operation in each mode are pre-installed in the ROM 51 as a program, and are realized by the CPU 52 sequentially decoding and executing the program.

First, in initial mode 1, immediately after power is turned on, valve V ₁ is ON, valves V ₂ to _{V 4} are OFF, and pump 7 is
OFF, the heater 2 is OFF, and the dialysate supplied from the dialysate supply unit 40 is in the dialysate tank 1.
flows into. A lower limit level sensor 23 is attached to the dialysate tank 1, and when the dialysate reaches the level of this level sensor 23, the level sensor 2
3 detects this, and the detection signal is taken into the CPU 52 via an input section 53 and an input/output section (I/O) 54. In response to this input signal, the CPU 52 sequentially reads out the instructions for the next step from the ROM 51, executes them, and shifts to liquid storage mode 2.

In liquid storage mode 2, the CPU 52 sends control signals to each output device via the I/O 54 and the output device control unit 55 to turn on the valve _V1 , turn on the pump 7, and turn on the heater 2.

The reason why this heater 2 is necessary is that the dialysate supply unit 4
This is because the temperature of the dialysate supplied from 0 to 0 decreases while it is being circulated, but this temperature decrease is 5 to 6
Since the temperature is approximately 100°C, a heater with a small heat capacity is sufficient.

Now, in this mode 2, the circulation pump 7
operates, so dialysate is supplied to the dialyzer 5.

Dialysate tank 1 and overflow tank 27
The liquid level in the overflow tank 2 rises and
When the overflow level of 7 is reached, an overflow occurs, and this overflow liquid is taken into the measuring tank 29.

In this embodiment, the measuring tank 29 has a small capacity of about 6 ml up to the full level sensor 30 (including the capacity of the piping line up to _V4 ), and the overflow liquid will soon reach the full level sensor in this tank. A detection level of 30 is reached. As a result, detection is immediately performed by the level sensor 30, and this detection signal is sent to the CPU via the input section 53 and I/O 54.
52. The CPU 52 reads and executes the program in the ROM 51, thereby transitioning to liquid storage mode 3.

In liquid storage mode 3, valves V ₁ to _{V 3} are OFF, V ₄
is turned on (the pump and heater remain in the same state), and all overflow liquid until the liquid levels in the dialysate tank 1 and overflow tank 27 become stable is drained via the measurement tank 29 and valve _V4 . In sync with this overflow detection,
The timer 56 operates and measures the time (2 to 5 minutes) until the liquid level stabilizes. In that example,
The measurement of the ultraviolet excess amount is started by pressing the measurement start switch 58 of the operation unit 57, but after the time has elapsed for the liquid level to stabilize, the lamp of the measurement start switch 58 turns off to indicate a measurable state. It blinks to prompt input of the start switch 58. When the measurement start switch 58 is pressed, the blinking lamp turns on and the switch ON signal is input to the CPU 52 via the input section 53 and I/O 54. The CPU reads the program in the ROM 51 and executes it, thereby transitioning to circulation mode 4.

In circulation mode 4, the valve V ₄ is turned OFF, and in the dialyzer 5, an amount of dialysate equal to the amount of water transferred from the blood to the dialysate side via the membrane overflows from the overflow tank 27, and the measuring tank 29
to be stored. This overflow liquid is in the measurement tank 29.
When the detection level of the full level sensor 30 is reached, the level sensor 30 operates and generates a detection signal. This signal is taken into the CPU 52 via the input section 53 and I/O 54. CPU is ROM51
By reading and executing the program within, the cycle mode 5 is entered.

In the circulation mode 5, the CPU 52 turns on the valve _V4 and calculates the extreme excess amount using the control signal. This calculation will be discussed later.

Circulation modes 4 and 5 are repeated several times, and in this embodiment, the entire circulation mode time is set within 10 minutes. When this time has elapsed, a signal is given from the timer 56 to the CPU 52, and the CPU 5
2 reads the program in the ROM 51 and executes it, thereby transitioning to the drain mode 6.

In drain mode 6, a control signal is given from the CPU 52 to each output device via the I/O 54 and the output device control section 55, valves V ₂ and V ₃ are turned ON, and the dialysate tank 1 and overflow tank 2 are turned on.
The dialysate in the dialysate tank 7 is drained, and the valve V ₂ is switched to connect port 1 to port 2, so that the dialysate flowing out of the dialyzer 5 is not returned to the dialysate tank 1 but instead flows through the flow tube 72. The liquid is drained through. In drainage mode 6, blood dialysis is continued in the dialyzer, but the ultraviolet amount is not measured and is corrected using the value in circulation mode. This correction will be described later. Now, when the dialysate level in the dialysate tank 1 decreases and the level is detected by the lower limit level sensor 23, this detection signal is taken into the CPU 52 via the input section 53 and I/O 54. The CPU 52 reads the program in the ROM 51 and executes it to set the liquid supply mode 7.
Move to 8.

The operation of liquid supply modes 7 and 8 is the same as that of liquid storage mode 2,
Since it is almost the same as 3, detailed explanation will be omitted.
However, in these liquid supply modes 7 and 8, unlike liquid storage modes 2 and 3, dialysis in the dialyzer continues to be performed. However, no measurement of ultraviolet doses was carried out;
Correct using the value in circulation mode.

Next, the calculation of the extreme excess amount and its correction in the second embodiment will be described.

In circulation mode 4, the full level sensor 30
The detection signal is taken into the CPU 52, and the timer 5
6 measures the time t _fi from closing the drain valve V ₄ of the measuring tank 29 until receiving the detection signal according to a command from the CPU, and the data is taken into the RAM 60 . On the other hand, the capacity V of the measuring tank 29 when it is full and the time of the circulation mode 5, that is, the time _td during which the draining valve _V4 of the measuring tank 29 is open, are stored in the ROM 51 in advance, and the CPU 52 stores these in advance. Based on the data, read the program in ROM51,
By executing the limit excess amount UF _R of the entire circulation mode repeated n times and its corresponding total time t _R
and the average ultraviolet flow rate UF _R /t _R are calculated, and the results are stored in the RAM 60 and displayed on the display unit 31.

Correction of the extreme excess amount in drain mode 6 is performed as follows. When the circulation mode setting time elapsed signal is taken into the CPU 52, the timer 56 starts.
The time t _p of the drain mode 6, that is, the time from when the valves V ₂ to V ₄ are turned ON until the lower limit level sensor 23 is turned OFF is measured according to a command from the CPU, and this data is stored in the RAM 60. CPU52 is RAM6
Using the data of t _p stored in 0 and the average ultra-overflow rate UF _R /t _R in the circulation mode, the correction amount (UF R /t _R
t _R )×t _D is calculated and stored in the RAM 60.

If the total time of liquid supply modes 7 and 8 is t _P , then the correction amount (UF _R /t _R ) x t _P can be calculated in the same way as the extreme excess amount in the liquid supply mode, and RAM
60.

CPU52 is the limit excess amount in circulation mode.
Add UF _R and the correction amount of ultra-overflow in drain mode and liquid supply mode, respectively (UF _R / t _R ) x t _D and (UF _R / t _R ) x t _P , and add this result to RAM60.
and display it on the display unit 31.

In this way, the measurement (including correction) of the ultra-limit excess amount is repeatedly performed with the circulation mode, liquid drain mode, and liquid supply mode as one cycle. To end the measurement, turn on the measurement end switch 59 of the operation section 57 to end the measurement.

The measuring unit 28 is not limited to the above example, and various other types can also be used. The configuration of the dialysate circulation system is not limited to the above example, and it is also possible to change the position of the circulation pump 7, the positions of various valves, the dialysate route, etc. Further, the circulation path is normally shut off, the dialysate from the dialysate supply unit 40 is supplied to the dialyzer 5, and the outflow dialysate from the dialyzer 5 is used as drainage, and the circulation path is periodically configured for a short time. do,
The ultra-limit excess amount may also be measured.

〔Effect of the invention〕

In this invention, the horizontal cross-sectional area of the overflow tank 27 is selected to be small to eliminate the influence of surface tension, so the overflow liquid becomes a stable and continuous flow, and the rise and change of the liquid level in the measuring tank is smooth. is a flat surface rather than a curved surface. Therefore, the measuring unit 28 can accurately detect the amount of overflowing dialysate, making it possible to accurately measure the ultraviolet amount.

When the ultra-large excess amount is small, in the conventional technology, the dialysate tank 1 overflows directly, so the horizontal cross-sectional area of the dialysate tank 1 is large, and the time required for one overflow to occur is shortened due to the influence of surface tension. become longer. Therefore, it is necessary to take a long time in the circulation mode, and as a result, the dialysis efficiency is reduced. The present invention eliminates these conventional drawbacks by choosing the horizontal cross-sectional area of the overflow tank 27 to be sufficiently small.

Furthermore, since the dialysate tank is open to the atmosphere, air bubbles in the dialysate are removed, and the number of air bubbles entering the dialyzer is extremely small compared to a non-circulating type (single pass type).

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of this invention.
2 is an operation flowchart of the embodiment shown in FIGS. 1 and 4, FIG. 3 is an explanatory diagram of the operation by mode of the embodiment shown in FIGS. 1 and 4, and FIG. 4 is another embodiment of the present invention. FIG. 5 is a block diagram showing an example of a conventional ultraviolet amount measuring mechanism. 1: Dialysate tank, 5: Dialyzer, 6: Flow control valve, 7: Circulation pump, 10: Dialysis membrane, 23: Lower limit level sensor, 24: Arithmetic control unit, 26: Communication pipe, 27: Overflow tank, 28 : measurement unit, 29: measurement tank, 30: full level sensor, 40: dialysate supply section, V ₁ to V ₄ : valve.

Claims (1)

[Claims] 1. A dialysate supply section, a dialysate tank, an overflow tank, a measuring unit, a dialyzer, a circulation pump, a first valve, a second valve, and a third valve.
The above-mentioned dialyzer is an ultraviolet excess measurement mechanism consisting of a valve and an arithmetic control unit, and the dialyzer has a blood chamber through which the patient's blood flows in and out and a dialysate chamber through which dialysate flows in and out through a dialysis membrane. The dialysate tank is configured such that water in the blood moves to the dialysate side through the dialysis membrane, and the dialysate tank is a tank that stores the dialysate supplied from the dialysate supply section, and has a lower limit level sensor. The overflow tank is in communication with the dialysate tank and has a horizontal cross-sectional area smaller than that of the dialysate tank, and the measurement unit includes a measurement tank for measuring dialysate overflowing from the overflow tank, and a measurement tank that measures the dialysate overflowing from the overflow tank. It consists of a level sensor and a drainage valve, the first valve is a valve that opens and closes a flow path connecting the dialysate supply section and the inlet of the dialysate tank, and the second valve is a valve that The valve has an inlet and two outlets, and the inlet is selectively connected to one of the outlets, and the third valve is a valve for draining the dialysate from the dialysate tank, and the dialysate between the outlet of the tank and the inlet of the dialysate chamber, between the outlet of the dialysate chamber and the inlet of the second valve, and between one outlet of the second valve and the inlet of the dialysate tank. They are connected by a flow path to form a circulation path for the dialysate, the circulation pump is a pump that is inserted into the circulation path and circulates the dialysate, and the arithmetic control section is configured to third valve,
Controls opening/closing or switching of the valve of the measurement unit, controls on/off of the circulation pump, receives detection signals from the lower limit level sensor and the full level sensor, and sends the dialysate from the dialysate supply section to the circulation path. A storage (supply) mode for storing dialysate, a circulation mode for circulating the stored dialysate, and a drain mode for draining the dialysate are sequentially controlled, and in the circulation mode, the overflow is controlled. The ultra-ultra-over amount measurement mechanism measures the ultra-ultra amount by measuring the dialysate overflowing from the tank using the above-mentioned measurement unit.