JPS6219217B2 - - Google Patents

Description

[Detailed Description of the Invention] (Object of the Invention) A siphon is provided in the fall path of liquid and water from a tank to intermittently transfer liquid or water.
This invention relates to a sanitary liquid transfer mechanism.

(Prior Art) Automatic dialysate preparation methods are broadly classified into metering pump type and metering tank type. Among these, the metering tank method has the major advantages of stable concentration of the prepared liquid, quiet operation, and fewer failures.
However, since the dialysate is prepared by repeatedly transferring the liquid accumulated in the tank to another tank using gravity, the time required for water to enter the mixing tank, the time for the dialysate to fall from the mixing tank, etc. Thus, the preparative capacity of this type of device is determined. Therefore, in order to increase the preparation capacity, it is necessary to use a valve with a large diameter to minimize the flow path resistance.

However, such large-diameter valves are not only large, heavy, and expensive, but also have many problems such as failure due to corrosion of the wetted parts and the proliferation of bacteria due to the complicated structure. It is.

(Structure of the Invention) In order to eliminate the above-mentioned drawbacks in the prior art, the present invention forms a siphon by processing a large-diameter pipe instead of a large-diameter valve, and uses a solenoid-type pinch valve to open and close the siphon for starting the siphon. This feature is characterized by the provision of a side road that allows for easy access.

The entire configuration of the dialysate preparation device according to the present invention is described in the first example.
As shown in the figure. P is a stock solution measuring section, which includes a stock solution measuring tank 3 equipped with a float-type level switch 4 that controls a solenoid-type pinch valve 2 that operates in conjunction with a pump 1 for pumping the stock solution, and a stock solution measuring section that measures the stock solution measured in the stock solution measuring tank 3. It consists of a siphon 5 to be derived. Q is the dilution water supply section, and the float type level switch 8
The water supply solenoid valve 9 is controlled by the water supply solenoid valve 9, and the negative pressure generating section 6 is operated by the water supply. From the bottom of the mixing tank 7 to the air backflow prevention tank 2 of the liquid storage tank 12
A siphon 13 (flow path A → D → B → C) is provided, which is made from a large diameter pipe up to 1.
Between B there is a side channel 15 with a solenoid pinch valve 14, thereby transferring the liquid in the mixing tank 7 to the storage tank 12 by forming a siphon.

FIG. 2 shows another embodiment in which, in place of the dilution water supply section Q of FIG. 1, a water storage tank 16 having a float type constant water level valve 22 and a siphon 17 for transferring water are provided. A siphon 17 made of a large diameter pipe is provided between the bottom of the water storage tank 16 and the air backflow prevention tank 21' of the mixing tank 7'.
A side passage 19 having a solenoid type pinch valve 18 for forming a siphon is connected between the passages A' and B' of the siphon 17, and a solenoid type pinch valve 20 for introducing air is connected to the top of the passage D' of the siphon 17. Further, as in the embodiment shown in FIG. 1, a siphon is provided from the mixing tank 7' to the liquid storage tank 122.

At the bottoms of the liquid storage tank 12 and the mixing tank 7' where the outflow ports of the siphons 13 and 17 are located, small-capacity air backflow prevention tanks 21 and 21' are provided.

(Action of the invention) The action of the invention will be explained using an actual dialysate preparation device. In conjunction with the start-up of the pump 1 for pumping in the stock solution, the solenoid type pinch valve 2 opens, and the stock solution flows into the stock solution measuring tank 3. Raw solution measuring tank 3
When the stock solution inside reaches a certain level, the float type level switch 4 operates to stop the stock solution pump 1, and at the same time, the solenoid type pinch valve 2 is activated.
closes, and one measurement of the stock solution is completed.

Next, open the water supply solenoid valve 9 and pour water into the mixing tank 7.
Inject into. At this time, by the action of the negative pressure generator 6, the stock solution in the stock solution measuring tank 3 is sucked and flows into the mixing tank 7 together with water through the siphon 5. When the liquid level in the mixing tank 7 reaches a predetermined position, the float type level switch 8 operates to close the water supply solenoid valve 9 and stop the water injection. Thereupon, the pump 10 is operated to circulate the liquid in the mixing tank 7 through the concentration measuring tank 11 and stir it while checking the concentration. As described above, a dialysate of a required concentration is prepared in the mixing tank 7.

Next, when the solenoid pinch valve 14 is opened, the dialysate in the mixing tank 7 flows into the liquid storage tank 12 through the channels A→B→C. At this time, the flow of the dialysate acts like a piston to push out or draw in the air inside the siphon 13 between the flow path B and C, and the air in the siphon 13 interacts with the outside of the siphon 13, that is, with the siphon 13. The liquid is carried out to the gas phase part of the liquid storage tank 12, where it is isolated. The amount of air within the siphon 13 is therefore reduced. Therefore, according to Boissjar's law, the equation of state p=νRT/
In v (where p is the pressure (degree of vacuum) inside the siphon 13, ν is the number of moles of air inside the siphon 13, R is the gas constant, T is the absolute temperature, and v is the volume of the air inside the siphon 13), Since the amount of air ν decreases with R, T, and v constant, the pressure (degree of vacuum) p of the air inside the siphon 13 decreases. Along with this, the liquid column rises in the direction A→D within the siphon 13 toward pressure equilibrium, and eventually reaches its top, forming a siphon. As a result, the dialysate in the mixing tank 7 passes through the siphon 13 and passes through the liquid storage tank 1.
2 will fall in a short time. This preparation siphon is repeated to replenish the dialysate into the liquid storage tank 12.

The embodiment shown in FIG. 2 utilizes a water storage tank 16 equipped with a float type constant water level valve 22 to supply dilution water to a mixing tank 7'.

When the measurement of the stock solution in the stock solution measuring tank 3 is completed, the solenoid type pinch valve 1 for siphon formation is activated.
8 opens and the water in the water storage tank 16 flows through the flow path A'-B'-
It flows through C' and the pressure drop in C' forms a siphon, causing the water and stock solution to fall all at once into the mixing tank 7'. When the liquid level in the mixing tank 7' reaches a predetermined level, the float type level switch 8 operates to open the solenoid type pinch valve 20 for air introduction and stop the siphon action, thereby interrupting the water supply. do. The subsequent stirring, mixing, transfer to the liquid storage tank 12, etc. are exactly the same as in the embodiment shown in FIG.

(Effects of the invention) Instead of the conventional large-diameter electric ball valve, a siphon made of a large-diameter pipe is used to create a compact,
By cleverly utilizing a lightweight, inexpensive, and sanitary solenoid-type pinch valve, the siphon is controlled and the performance is comparable to that of an electric ball valve.

Furthermore, the mechanism of the present invention does not use any metal that is susceptible to corrosion in the liquid contact parts, has an extremely simple structure, and is easy to clean, compared to conventional systems in terms of hygiene, which is the most important aspect of medical equipment. It has excellent features. This also greatly contributes to reducing failures, extending product life, and improving reliability.

[Brief explanation of the drawing]

Figure 1 is a piping diagram of the embodiment of the present invention, Figure 2 is the same,
It is a piping diagram of another Example. Explanation of symbols of main parts, 2, 14, 18, 20
... Solenoid type pinch valve, 3... Raw solution measuring tank, 4, 8... Float type level switch, 7,
7′...mixing tank, 122...liquid storage tank, 13,
17... Siphon, 15, 19... Side channel, 16... Water storage tank, 21, 21'... Air backflow prevention tank, P... Stock solution measuring section, Q, Q'... Dilution water supply section.

Claims (1)

[Claims] 1. In an apparatus for preparing a solution of a desired concentration by diluting and mixing a certain amount of stock solution with water, a siphon 13 is provided between a mixing tank 7 and a storage tank 12, and a siphon is connected to the siphon. A liquid transfer mechanism formed by connecting a side passage 15 having a forming solenoid type pinch valve 14. 2. A water storage tank 16 having a constant water level valve 22 is provided at the top of the measuring tank type chemical liquid preparation device, and a solenoid type pinch valve 18 for forming a siphon is installed in the siphon 17 provided between the water storage tank 16 and the mixing tank 7'. 2. The liquid transfer mechanism according to claim 1, further comprising a side passage 19 having a side passage 19 and a solenoid type pinch valve 20 for introducing air. 3. The liquid transfer mechanism according to claim 1 or 2, characterized in that a small-capacity air backflow prevention tank is provided at the liquid outlet of the siphon.