JP2912801B2 - Hemodialysis machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hemodialysis apparatus used for treating renal failure patients, and more particularly, to a valve for controlling a flow rate of a dialysate.

[0002]

2. Description of the Related Art Dialysis therapy not only removes waste products in the blood but also plays a so-called water-removing role of removing water consumed by a dialysis patient who does not produce urine. Incorrect control of water removal may endanger the patient's life, and hemodialysis apparatuses are required to have strict water removal control performance.

[0003] Therefore, in this type of conventional apparatus, the flow rate of the dialysate supplied and drained to the equal volume meter is controlled by opening and closing a valve, and the dialyser is kept constant from the equal volume meter. A volume of dialysate is being supplied.

That is, as shown in FIG. 3, an equal volume meter 32 is provided on a path of a dialysate supply pipe 30 and a dialysate discharge pipe 31 connected to a dialyzer. A valve 33 is interposed at a connection point between each of the pipes 30 and 31 and the equal-capacity measuring device 32, and the opening and closing operation of the valve 33 controls the flow of dialysate into and out of the equal-capacity measuring device. As shown in FIG. 4, the valve 33 has three ports, and is provided with flow paths a, b, c branched in three directions and a piston 34. Then, by switching the piston 34 in the direction indicated by the arrow in the same figure, the piston 34 is switched to the flow path between the flow paths a and b or the flow path between the flow paths bc, and always forms a bifurcated flow path. .

[0005]

However, in the valve 33 used in this conventional hemodialysis apparatus, when the piston 34 moves to a position shown by a two-dot chain line in FIG. It is circulated to form a three-branch flow path. For this reason, a channel a-c that should not be formed is formed,
Every time the valve is opened and closed, a flow rate error of the dialysate with respect to the equal volume meter 32 occurs. The flow rate error every time the valve 33 is opened and closed is very small and can be ignored. However, as hemodialysis is performed for a long time, the number of times the valve 33 is opened and closed increases, resulting in a non-negligible flow rate error. As a result, when performing hemodialysis for a long time, there was a possibility that accurate water removal could not be performed.

[0006] The present invention has been made in view of the problems existing in such conventional technology, and an object of the present invention is to remove water even if hemodialysis is performed for a long time. It is an object of the present invention to provide a hemodialysis apparatus capable of surely preventing the occurrence of dialysis.

[0007]

SUMMARY OF THE INVENTION To solve the above problems, the present invention provides a dialyzer for contacting blood with a dialysate through a permeable membrane to remove waste and water from the blood, Displaceable partition separates liquid supply chamber and drain chamber
And both chambers are connected to the dialyzer,
Dialysate before dialysis treatment flowing out of the chamber to the dialyzer,
Dialysate after dialysis treatment flowing into the drainage chamber from the dialyzer
An equal-volume meter that flows in and out of the same volume;
Pipes connected to the dialyzer in each chamber of the vessel
A first two-way valve for opening and closing each pipe line,
Supply dialysate before dialysis to the liquid metering chamber
The dialysis process is carried out from
Installed in each of the conduits from which the dialysate after treatment is discharged.
And a second two-way valve for opening and closing each pipeline, and the first two-way valve
Valve control means capable of independently opening and closing the valve and the second two-way valve
And any one of the first two-way valve or the second two-way valve
When one of the valves is closed, a control means for opening and controlling the other valve after a lapse of a closing operation response time from the start of closing to the completion of closing is provided.

[0008]

Therefore, the first two-way valve is closed by the above means.
With the second two-way valve open, place the dialysis treatment
Dialysate is supplied and drained by the amount supplied
The dialysate after the dialysis treatment is discharged from the chamber. And the first
With the two-way valve open and the second two-way valve closed
Dialysate is supplied to the dialyzer from the chamber before dialysis
And dialysis treatment from dialyzer by the amount supplied
Later dialysate flows into the drainage chamber. Repeat these operations
Thus, a dialysis treatment is performed. Where the first two
Either the valve or the second two-way valve is open
When closing the valve, the valve control means and the control means
Closing operation response from the start of closing of one valve to the completion of closing
The other valve opens after a certain time
You. For this reason, both two-way valves are opened at the same time.
Flow rate error for equal volume meter
It becomes possible to reduce.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, a dialyzer 1 for purifying blood is separated into a blood chamber 2 and a dialysate chamber 3 by a semipermeable membrane. A blood pipe 4 is connected between the blood chamber 2 and the human body 5, and blood from the human body 5 is circulated through the blood chamber 2. The dialysate chamber 3 is connected with a dialysate supply pipe 6 and a dialysate discharge pipe 7 as pipes. The dialysate before use is connected with the dialysate used through the dialysate supply pipe 6 through the dialysate chamber 3. Dialysate discharge pipe 7
Is discharged to

On the path of the dialysate supply pipe 6 and the dialysate discharge pipe 7, there are provided a buffer container 8 and an equal volume container 9 as equal volume measuring devices. A substantially hemispherical diaphragm 10 made of an elastic rubber material is provided in the buffer container 8 so as to be displaceable.
And a drainage chamber 12. And the diaphragm 10
The dialysate corresponding to the displacement volume is sent to the dialysate chamber 3 of the dialyzer 1 by the displacement of
Is to be pulled out of.

Since the equivalent container 9 has the same structure as the buffer container 8, its description is omitted. However, as will be described below for distinguishing the buffer container 8 from the buffer container 8, another reference numeral is given. That is, the equivalent volume container 9 is provided with a diaphragm 13 corresponding to the diaphragm 10, and is separated by the diaphragm 13 into a liquid supply chamber 14 and a drainage chamber 15.

A metering pump 16 is provided on the downstream side of the dialysate supply pipe 6, and a liquid supply pump 17 is provided on the upstream side. A drainage pump 18 is provided on the path of the dialysate discharge pipe 7 between the buffer container 8 and the equal volume container 9. Each pump 16
To 18 are connected to a controller 23 as first and second control means, and the controller 23
By controlling the rotation of 6, the flow rate of the dialysate flowing through both pipes 6, 7 is adjusted.

On the path of the dialysate supply pipe 6, electromagnetic valves 19 and 20 as first or second valves are provided. On the path of the dialysate discharge pipe 7, electromagnetic valves 21 and 22 as first or second valves are provided. The opening response time from the start of opening to the completion of opening of each of the solenoid valves 19 to 22 or the closing response time from the start of closing to the completion of closing is the same.

The solenoid valves 19 to 22 are connected to a controller 23.
And a ROM (not shown) provided in the controller 23 stores a closing response time from the open state to the completion of closing of the solenoid valves 19 to 22. In this embodiment, the closing response time is set to 50 msec.

The controller 23 includes a solenoid valve 19,
At the time of closing of 21, after the closing response time elapses, the other solenoid valves 20 and 22 are controlled to start opening. Also,
When the solenoid valves 20 and 22 are closed, the controller 23 controls the other solenoid valves 19 and 21 to open after the closing response time elapses.

A flow sensor 24, 25 capable of detecting whether the flow of dialysate has stopped is provided on the dialysate supply pipe 6.
Are provided, and the flow sensors 24 and 25 are connected to the controller 23. Based on the detection signal from the flow sensor 24, the controller 23 detects the full liquid state of the buffer vessel 8 and an equal amount container 9.

Next, a series of operations and effects in the dialysis apparatus configured as described above will be described. In the initial state before the start of dialysis, the solenoid valves 20 and 22 are open and the solenoid valves 19 and 21 are closed. A discharge chambers 12 dialysate spent liquid supply chamber 14 is fully liquid state and the buffer vessel 8 dialysate equal volume container 9 (hereinafter, referred dialysate spent with "dialysis effluent" The dialysate before use is referred to as “dialysate”). That is, the liquid supply chamber 11 of the drainage chamber 15 and the buffer vessel 8 equal dose containers 9 to be put into a minimum volume.

In the initial state, the flow sensor 2
When the buffer container 8 and the equal-capacity container 9 are detected to be in the full state at 4 and 25, the controller 23 sets the solenoid valve 2
Close 0,22. Subsequently, after the closing response time of the solenoid valves 20 and 22 has elapsed, the controller 23 controls the solenoid valves 19 and 21.
To release. At this time, since the solenoid valves 19 and 21 are opened after the solenoid valves 20 and 22 are completely closed, the dialysate supply pipe 6 and the dialysate discharge pipe 7 are in communication with each other via the equivalent container 9. There is no.

Next, the controller 23 controls the drainage pump 18
Is operated, and the dialysis drainage in the drainage chamber 12 of the buffer container 8 is discharged.
Send to drainage chamber 15 equal dose containers 9, equal amounts vessel 9 by the pressure
The dialysate in the liquid supply chamber 14 is sent downstream of the liquid supply pipe 6.

At this time, the metering pump 16 is connected to the drainage pump 1
If the flow rate is set to be smaller than 8, a part of the dialysate sent downstream from the liquid supply chamber 14 of the equal volume container 9 is directly sent to the dialyzer 1, and the rest is supplied to the liquid supply chamber 11 of the buffer container 8. Will remain. The drainage chamber 15 of the equivalent container 9 has a dialyzer 1
The liquid supply chamber 14 of the equivalent volume container 9 is reduced while the liquid supply chamber 14 is expanded by the drainage from the container, and the displacement of the diaphragm 13 reaches the limit.

Then, it is detected by the flow sensors 24 and 25 that the drainage chamber 15 of the equivalent container 9 is full. The controller 23 closes the solenoid valves 19 and 21 based on the detection signals from the flow sensors 24 and 25.
Subsequently, the controller 23 opens the solenoid valves 20, 22 after the opening response time of the solenoid valves 19, 21 has elapsed. At this time, after the solenoid valves 19 and 21 are completely closed,
Since 0 and 22 are opened, the dialysate supply pipe 6 and the dialysate discharge pipe 7 do not communicate with each other via the equivalent container 9.

The controller 23 controls the liquid supply pump 1
Activating the 7, the dialysate is fed into the fluid chamber 14 of equal amounts vessel 9, the diaphragm 13 is displaced to the discharge liquid chamber 15 side of the equal volume containers 9. Then, the liquid supply chamber 14 of the equal volume container 9 is filled with the new dialysate, and the dialysate in the drainage chamber 15 of the equal volume container 9 is drained to the outside.

In the buffer container 8, the metering pump 16
Removes the dialysate remaining in the liquid supply chamber 11 from the dialyzer 1.
The liquid is sent to the drainage chamber 12 of the buffer container 8 via the. After a lapse of a predetermined time, the diaphragm 10 of the buffer container 8 is displaced toward the liquid supply chamber 11 and reaches the limit.

Then, the flow sensors 24 and 25 detect that the drain chamber 12 of the buffer container 8 is full. Based on the detection signals of the flow sensors 24 and 25,
The controller 23 closes the solenoid valves 20 and 22 and opens the solenoid valves 19 and 21 after the closing response time elapses, and repeats the above operation.

Therefore, after one of the solenoid valves 20, 22 is completely closed, the other solenoid valve 19, 21 is opened,
Further, after one of the solenoid valves 19 and 21 is completely closed, the other solenoid valves 20 and 21 are opened, so that the discharge side and the supply side of the dialysate supply pipe 6 and the dialysate discharge pipe 7 communicate with each other. Never in a state. For this reason, every time the solenoid valves 19 to 22 are opened and closed, a flow rate error of the dialysate or the dialysis drainage with respect to the buffer container 8 or the equivalent container 9 can be eliminated. As a result, even if hemodialysis is performed for a long time, it is possible to prevent a water removal error from occurring.

The present invention is not limited to the above embodiment, but may be made as follows without departing from the spirit of the present invention. (1) As shown in FIG. 2, a container having a piston 26 may be used instead of the equivalent container 9. According to this configuration, the motor 27 is connected to the controller 23 via a drive circuit (not shown). The motor 2 has a mechanism 2
The piston 26 may be reciprocated by being connected to the piston 26 via the controller 8 and driving the motor 27 by the controller 23.

(2) Although the solenoid valves 19 to 22 are used in the above embodiment, other valves such as an electric type, an electro-hydraulic type, a hydraulic type, a hydraulic type or a vacuum type may be used. (3) In the above embodiment, the opening response time and closing response time of each of the solenoid valves 19 to 22 are set to 50 msec, but may be set to values longer than that.

[0028]

As described above in detail, according to the present invention, there is an excellent effect that a water removal error can be reliably prevented even if hemodialysis is performed for a long time.

[Brief description of the drawings]

FIG. 1 is a circuit diagram of a hemodialysis apparatus embodying the present invention.

FIG. 2 is a circuit diagram of a hemodialysis apparatus showing another embodiment.

FIG. 3 is a partial circuit diagram of a hemodialysis apparatus showing a conventional technique.

FIG. 4 is a cross-sectional view of a valve showing a conventional technique.

[Explanation of symbols]

1 dialyzer, 6 dialysate supply pipe (pipe), 7
... dialysate discharge pipe (line), 9 ... equal volume container (equal volume meter)
Meter), 13: diaphragm, 14: liquid supply chamber, 15: drainage chamber, 1
9, 21 ... solenoid valve (first two-way valve), 20, 22 ... solenoid
Valve (second two-way valve), 23 ... Controller (valve control hand)
Stage, control means).

Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) A61M 1/14 511

Claims (1)

(57) [Claims] 1. A dialyzer for removing waste and water from blood by bringing blood and dialysate into contact with each other through a permeable membrane, and a liquid supply chamber and a drainage chamber divided by a displaceable partition, Both rooms
Connected to the dialyzer,
The dialysate before dialysis flowing out to the
Equal volume with the dialysate after dialysis treatment that flows into the drainage chamber from the
Equal volume meter that flows in and out, and is connected to the dialyzer in each chamber of the equal volume meter.
The first two are provided in each of the pipelines, and open and close each pipeline.
And-way valve, the dialysate before being dialyzed into fluid chamber of said equal volume meter
From the drain line for supplying
Installed in each of the pipelines where the dialysate after dialysis is discharged
The second two-way valve that opens and closes each pipeline, and the first two-way valve and the second two-way valve can be opened and closed independently.
Valve control means, and either one of the first two-way valve or the second two-way valve
A control means for controlling the opening of the other valve after the elapse of a closing operation response time from the start of closing to the completion of closing when closing one of the valves.