JP2000253763A - Device for feeding prescribed small flow rate liquid from container of constant volume - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a structure capable of adjusting a flow rate widely in a simple device capable of flowing out a small flow rate liquid from a constant volume container to an open atmospheric state stably for a long period of time by controlling in a prescribed flow rate. SOLUTION: This device for feeding a prescribed small flow rate liquid has a container 22 having a constant volume, capable of housing a liquid and arranged with an opening part facing downward, a flowing out hole 14 for the liquid communicating with the opening part and a bubble-generating pipe 16, is provided by arranging an exuding member 15 for reducing the effect of the surface tension of air and water at the flowing out hole and also capable of adjusting the perpendicular distance of the bubble-generating end toward the flowing out hole of the liquid so as to be able to hold a pressure associated with the flowing out of the liquid against the effect of the surface tension of the liquid making a contact with air as a necessary constant value, and further an exchangeable capillary 33 in the tubular passage connected to the bubble- generating pipe for introducing an atmosphere to provide a means for controlling the introduced air flow rate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the technical field of fluid engineering, including horticulture and medical treatment, which needs to control the supply of liquid over a long period of time, such as the supply of water and the supply of nutrients to living organisms.

[0002]

2. Description of the Related Art A plug is attached to an outlet as a drip water supply device using a PET bottle, and a tube for adjusting the air flow rate is crushed by a bubble generating pipe having an inclined end face for air introduction and a plastic tube connected to the plug on the outlet. 2mm for liquid outflow at the bottom of the stopper
There is a simple device for supplying a liquid by providing a small amount of holes.

[0003]

2. Description of the Related Art In the prior art, the influence of surface tension on the end face of bubble generation is not sufficiently considered to be constant or small, and the pressure difference in bubble generation / separation is not constant.
In order to control the air flow rate, the flow rate area changes over time as the ratio is large because the plastic tube is simply squeezed by crushing the plastic tube. Essentially, stable flow rate control cannot be performed over 10 hours. There was a problem. Further, the hole of the liquid outflow is also greatly affected by the surface tension, and there remains a problem that the outflow resistance, that is, the differential pressure changes depending on external conditions.

[0004]

The flow rate of the liquid is set at 0.
An object of the present invention is to realize, with a simple device, a mechanism that can stably and stably control a flow rate as low as about 01 mL / min over a long period of time of 100 hours or more. It is an object of the present invention to provide a device which can keep the influence of tension small and stable and can change the flow rate greatly by adjustment.

[0005]

Means for Solving the Problems Although flow control and pressure are always in a back-to-back relationship, in a flow path having a small shape, the surface tension corresponding to the curvature of the boundary surface where air and liquid come into contact is related to the pressure difference. We have taken measures to keep this effect small and constant. That is, the air bubbles are directed downward or directly upward from the air side so as to arrange the bubble-generating portion almost horizontally as a circular cross section. For example, in the case of water and air, 150 Pa for 2 mm diameter and 75 P for 4 mm diameter
The required increase value of the internal pressure of the bubble a was made substantially constant. Further, in the part where the liquid flows out, the diameter of the flow path to the outflow hole is set to 4 mm or more so that the influence of surface tension can be further reduced. I made it.

As a means for rationally and stably controlling the flow rate using the relationship between the flow rate and the pressure drop, a method using a stainless steel capillary having an inner diameter of 0.3 mm or less as a laminar flow resistance flow path having a proportional relation. It was adopted. At a steady flow rate, it is usually appropriate to control the pressure drop due to the capillary in the range of approximately 50 to 300 Pa. In the entire flow path system, the hydraulic pressure difference from the bubble generation end to the liquid outflow portion, that is, the water head, is used. From this value, the remaining main pressure of the head, taking into account the required pressure based on the surface tension at the bubble generating end and the liquid outlet, is balanced in the capillary in accordance with the flow rate. At this time, if the base water head can be adjusted to some extent, and several types of capillaries are prepared so that they can be easily replaced, precise flow rate adjustment over a wide range becomes possible.

Further, as a water supply device used for horticulture or the like, it is sufficient that the flow rate is constant within one to several hours. As a device corresponding to this, a means for collecting water flowing out at a constant flow rate, providing a separate flow path, and guiding a collective amount at a required position at a time interval is also taken.

In particular, when used for horticulture or the like, it is sometimes desirable to set the water supply interval longer than several hours to about one day. In order to cope with this, the container for storing the water flowing out at a constant flow rate is configured to be appropriately large, and when leading from this container to another container, the height to the top is appropriately selected by using the action of the siphon. In this way, the structure is such that the volume can be set up to about 50 to 500 mL as a united volume from the container.

[0009]

1 and 2 show an embodiment of an apparatus for supplying a constant flow rate of liquid from a constant volume container according to the present invention.
The explanation will be made with reference to the sectional explanatory view of FIG. Container 2 of constant volume in FIG.
The second outlet 23 is arranged downward, and the stopper 11, which is a liquid outlet pipe adapted to the inner surface 24 of the outlet, is securely attached via the O-ring 12 in an airtight manner. The stopper 11 is provided with an air intake hole 13 at a portion immediately below the outlet 23 of the container, and an L-shaped air bubble generating pipe 16 is inserted in an airtight manner. At an appropriate position below the stopper 11, one or more liquid outflow holes 14 having a diameter of about 4 mm or more are provided, and a leaching member 15 made of a wettable material such as a cotton cloth is provided on the outside thereof, if necessary. Is attached to the outside of the stopper 11 in an annular shape to prevent the liquid from temporarily flowing out excessively immediately after the container 22 is inverted and to stabilize the influence of the surface tension at the outlet hole 14. I do. The interior of the container 22 is divided into a liquid part 2 and an air part 5.

The portion of the L-shaped air bubble generating pipe 16 to be inserted into the stopper 11 is bent at a right angle and is directed downward. The bottom of the tube 18 is a bubble generating end 19, where the air bubbles 3 grow until they are released into the liquid.
When the bubble generating end 19 is a horizontal cut surface, the size of the bubble is substantially constant under the influence of the outer diameter thereof. Become. The bubbles 4 grown before leaving the bubble generating end 19 rise in the liquid 2 and enter the air portion 5 at the top of the container 22. At this time, the inner diameter of the bubble generating end 19 is extremely important and needs to be set to an appropriate size of 2 mm or more in order to keep the influence of the surface tension of the liquid small and constant.
Of course, it is usually difficult to make it 4 mm or more due to shape restrictions.

A flexible air introducing pipe 32 such as a vinyl tube is connected to an outer end of the air bubble generating pipe 16, and an air introducing section 30 arranged on the upper outside of the container 22.
Linked to 0.1-0.3 mm for the air inlet 30
A capillary 33 having an appropriate inner diameter and length within the range is connected to the air introduction pipe 32 in a hermetically sealed manner with a holding tube 34, and the outside is covered with a silicone rubber tube 35 in which an air filter 31 is arranged. It is detachably mounted by means of a tape ring 36 affixed at an appropriate position on the outside.

The liquid that has oozed from the leaching part 15 travels along the outer surface of the plug 11 and drops as a drop 7, but is collected in a water reservoir 41 provided annularly at the lower end of the plug 11. Pool 41
A drain pipe 54 having a substantially horizontal end face is disposed close to the bottom surface 42 of the water reservoir 41 and has a top portion 43 of an appropriate height.
Drain pipe end 55 lower than the bottom 42 of the reservoir 41 via
Is configured. When the liquid is accumulated in the sump 41 and the water level becomes higher than the top 43 to a certain extent, the liquid is automatically discharged from the sump 41 by the siphon action and is continuously discharged until the water level becomes close to the bottom surface 42. . The amount of accumulation / discharge at one time is determined by the horizontal area of the water reservoir 41, the height up to the top 43, and the position of the lower end of the discharge pipe 54, and the time interval of discharge is appropriately set. For example, almost 1
Every two hours, 150 mL of water can be drained to the required location.

FIG. 2 illustrates, as a second embodiment, an example in which a bubble generating pipe 46 and a liquid outlet pipe 50 are attached to a bottom surface 45 of the lid using a lid 44 adapted to the container 22 having a fixed volume. The lid 44 is normally screwed onto a screw 25 provided on the outside of the outlet 23 of the container 22 and is easily airtightly attached to the outlet 23. A bubble generating pipe 46 is fixed to the bottom surface 45 of the lid 44 with the bubble generating end 47 facing upward, and the inner diameter of the bubble generating end 47 needs to be kept constant so that the effect of the surface tension of the liquid is 2 to 4 mm small. However, the upwardly directed portion should not have its inner diameter smaller than the end. Moreover, it is desirable that the length of the upward portion is 5 mm or less.

The liquid outlet pipe 50 is, for example, a screw 48 and a nut 4 so that the position thereof can be adjusted vertically with respect to the lid 44.
Attach via 9. The inner diameter of the liquid outflow pipe 50 is 4 mm
The above is appropriate and it is necessary that the liquid in the container 22 is naturally filled inside. A liquid outflow hole 52 with a diameter of about 4 mm or more is provided at an appropriate position, and a leaching portion 53 made of a material that is easily wetted is disposed outside the liquid outflow hole 52, so that the influence of surface tension on the outflow of liquid into the air is small and stable. To be able to

The upstream side of the bubble generating pipe 46 is the same as that shown in FIG. 1, and the air introducing pipe 32 is connected to the air introducing section 3.
Connected to 0.

The liquid that has oozed from the leaching portion 53 travels along the outer surface of the liquid outflow pipe 50 to become a drop 7 and descends. However, the liquid is accumulated in the water reservoir 41 provided annularly at the lower end of the liquid outflow pipe 50. Simply, when the appropriate water level is reached, the drain 5
From 6, it is discharged at a required position via a distribution tube 57 at intervals. In this case, the water level becomes a water level corresponding to the resistance including the gradient on the discharge side and the bubbles in the path,
mm or less.

In the example of FIG. 1, the height difference H0 between the bubble generating end 19 and the liquid outflow hole 14 is shown, and in the example of FIG. 2, the height difference H0 between the bubble generating end 47 and the liquid outflow hole 52 is shown. It is necessary to set the pressure higher than the pressure corresponding to the surface tension in each channel system so that a pressure drop corresponding to the flow rate can be sufficiently obtained by the capillary 33 of the air introduction unit 30. is there. Normal flow range is 1:50 by adjusting H0 and selecting capillary.
The setting can be changed to 0 or more.

[0018]

According to the apparatus for supplying a constant low flow rate liquid from a constant volume container according to the present invention, a very low flow rate liquid of about 0.01 mL / min can be supplied for a long time of 20 days or more by a simple mechanism and structure. It is possible to continue to flow automatically and stably over the whole area. Of course, for a larger flow rate, stable flow rate control is possible more easily.
In particular, there is an effect that water supply of a flower pot or a plant tank for gardening can be realized by a very simple device using a plastic bottle of about 2 L in a period of one week or more. At this time, it is also possible to supply water at appropriate time intervals.

Further, since the flow rate can be precisely controlled for a small flow rate, it can be applied to medical and other wide fields.

[0020]

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of an apparatus using a stopper that fits inside an outlet of a container as one of apparatuses for supplying a constant small flow rate of liquid from a constant volume container according to the present invention.

FIG. 2 is a schematic cross-sectional view of another apparatus for supplying a constant small flow rate of liquid from a constant-volume container according to the present invention, using a lid that fits outside the outlet of the container.

[Explanation of symbols]

 2 Liquid 3 Bubble 4 Bubble 5 Part of air 7 Drop 11 Plug 12 O-ring 13 Air intake hole 14 Outflow hole 15 Leaching member 16 Bubble generation pipe 17 Screw 18 Control tube 19 Bubble generation end 22 Constant volume container 23 Outlet 24 Inner surface 25 Screw 30 Air introduction part 31 Air filter 32 Air introduction tube 33 Capillary 34 Holding tube 35 Silicon tube 36 Ring 41 Water reservoir 42 Bottom surface 43 Top top 44 Cover 45 Bottom surface 46 Bubble generating pipe 47 Bubble generating end 48 Screw 49 Nut 50 Liquid Outflow pipe 52 Outflow hole 53 Leaching member 54 Drain pipe 55 Drain pipe end 56 Drain port 57 Distribution tube

Claims (6)

[Claims] 1. An outlet of a fixed volume container containing water or other liquid is installed facing downward, and an air intake hole is provided on an upper side surface of a closed plug having a pipe-like lower end adapted to the outlet. The outlet end on the liquid side of the L-shaped air bubble generating pipe which is hermetically inserted into this hole is directed downward, and the tip is made to have a structure in which the length can be adjusted. As a bubble generation end that can secure an almost constant value of internal pressure increase of bubbles based on the surface tension of liquid and air, when air with a very small flow rate is introduced, bubbles of air are introduced into the liquid at almost constant time intervals. A mechanism capable of stably generating the air is connected, and a flexible air introduction pipe such as a vinyl tube is connected to the outer end, guided upward, and connected to the air introduction section. On the lower side of the stopper, an appropriate distance from the bubble generation end is 10 to 4
One or more liquid outflow holes with an inner diameter of about 4 mm or more are provided 5 mm below to allow the liquid to flow out, and a leaching part such as a cotton cloth made of a fibrous material or the like that is easily wetted by the liquid is arranged outside the liquid. In order to keep the influence of the surface tension on the outflow of the liquid small and constant, a very small flow rate of the liquid is leached in accordance with the pressure difference with the outside air, and the outside of the stopper is dripped. Has an inner diameter of 0.1-0.
A capillary with an appropriate length of 3 mm is placed and 35 to 350 Pa for an air flow rate of 0.001 to 1 mL / min.
A constant-volume container that allows appropriate flow rate control by generating a differential pressure of, and introduces air into the container as air bubbles in response to a constant flow of liquid flowing out and dripping from a container of constant volume. A device that supplies a constant small flow of liquid from 2. An air bubble generating pipe and a liquid outflow at a bottom surface of the lid in the apparatus for supplying a constant small flow rate of liquid from the constant volume container according to the above item 1, using a lid adapted to an outlet of the container. Install the tube. The bubble generating pipe is attached with a bubble generating end with an inner diameter of 2 to 4 mm facing upward inside the lid, and a flexible air introducing pipe such as a vinyl tube is connected to the outer end to guide the air upward. Connect to the introduction. The liquid outflow pipe has a structure with an inner diameter of about 4 mm or more, with the upper end inside the lid and a screw that can be adjusted vertically to secure airtightness to the lid, so that the liquid can easily enter the inside and fill it. At least one liquid outlet having an inner diameter of about 4 mm or more is provided at a position 10 to 45 mm below the bubble generating end outside the lid to allow the liquid to flow out, and further to the outside of the lid to easily wet the liquid. A leaching part such as a cotton cloth made of a material is placed to keep the influence of surface tension on the outflow of liquid small and constant, and the liquid is leached at a very small flow rate according to the pressure difference with the outside air. The outside of the outflow pipe is configured to be dripped, and the inside diameter of the air introduction section is 0.1 to 0.1 mm.
A capillary having an appropriate length of 3 mm is arranged to generate a differential pressure of 35 to 350 Pa with respect to an air flow rate of 0.01 to 1 mL / min to enable appropriate flow rate control. A device for supplying a constant small flow rate of liquid from a constant volume container in which air is introduced into the container as air bubbles in response to the liquid flowing out and dripping. 3. A device for supplying a fixed flow rate of liquid from a constant volume container according to the above items 1 and 2, wherein the liquid dropped on the outside of the stopper or the liquid outlet pipe is collected and stored in a container whose upper part is opened. An appropriate flexible tube or gutter is attached to the lower part of the container, and a constant volume container is automatically supplied to the required position at an appropriate time interval according to the characteristics such as the gradient of the flow path and the head. A device that supplies a flow of liquid. 4. When the liquid dropped on the outside of the stopper or the liquid outlet pipe of the above item 3 is collected and stored in a container whose upper part is opened, a position close to a lower bottom surface in the container from an appropriate height position of the container. A pipe with an almost horizontal end face is arranged so that the liquid can accumulate in a container more than a certain amount, descend from the top of the pipe, start flowing by the action of the siphon, and flow out to near the lower bottom in a short time. Then, the liquid is stopped from flowing out of the pipeline until the liquid has accumulated in the container more than a certain amount.The horizontal area of the container and the height corresponding to the siphon action of the pipeline are appropriately set, and the A device for supplying a liquid with a constant small flow rate from a constant volume container in which the amount and time interval flowing out over time can be appropriately selected. 5. A constant volume container capable of storing a liquid to be discharged, a liquid outlet tube having a liquid outlet for communicating the liquid with an outlet of the constant volume container, and a liquid outlet, and inside the liquid outlet tube or the constant volume container. An air bubble generating pipe having a bubble generating port having a diameter of 2 to 4 mm inside, and an inner diameter of 0.1 to 0.3 mm which communicates with the air bubble generating pipe and has a function of controlling a flow rate.
An air introduction member provided with a capillary of the type described above, wherein a vertical distance between the bubble generation port and the liquid outlet is 1
An apparatus for supplying a constant small flow rate of liquid from a constant volume container characterized by being variably configured to have a length of 0 mm or more. 6. A container having a constant volume and capable of storing a liquid with an opening facing downward, a liquid outlet and a bubble generating pipe connected to the opening, and a surface of air and liquid at the liquid outlet. A leaching member that reduces the influence of tension is arranged, and the vertical distance of the bubble generation end from the liquid outflow hole can be adjusted so that it is related to the outflow of liquid against the effect of surface tension of the liquid in contact with air. It is possible to keep the pressure constant at the required value, and furthermore, it is possible to control the introduced air flow rate by installing a replaceable capillary connected to the bubble generation pipe and installing a replaceable capillary in the pipe that introduces air. An apparatus for supplying a constant small flow rate of liquid from a constant volume container.