JPH05248350A - Pipe structure and pump - Google Patents

Abstract

PURPOSE:To provide a pipe structure capable of stably discharging trace amounts of fluids by providing an outer peripheral pipe concentric with and around the outer periphery of a flexible center pipe, forming a fluid sealing space between both of the pipes, and sealing a fluid in the space. CONSTITUTION:A pipe structure 10 which is suitably used in the medical field in feeding medical fluids by trace amounts into a human body by means of a computer-controlled accurate pump is formed of a flexible synthetic resin material. The structure includes a center pipe 11 and an outer peripheral pump 12 concentric with each other, and an annular fluid sealing space 13 is formed between both of the pipes 11, 12. A swelling portion 14 serving as a pressure regulation means is formed at one part of the fluid sealing space 13 and the fluid sealing area 13 and the swelling portion 14 are both filled with a fluid 15 so that expansion and contraction do not occur microscopically at the pipe portion. The center pipe 11 is connected to an injection nozzle (or neelde)16 at one end and to a cylinder pump (syringe) 16 at the other end.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a pipe structure, and more particularly to a flexible pipe structure suitable for stably ejecting an extremely small amount of fluid.

[0002]

2. Description of the Related Art In the medical field, for example, an attempt has been made to deliver a very small amount of a drug solution into a human body through a pipe by a precision pump managed by a computer. However, the pipe is required to have flexibility, and the intravascular pressure of the human body fluctuates according to the fluctuating blood pressure. Furthermore, minute pressure fluctuations cannot be avoided on the precision pump side. For this reason, it has been found that it is extremely difficult to strictly stabilize the discharge amount of the ultra-small amount of fluid, because the pipe expands and contracts its cross-sectional area when viewed microscopically, resulting in pulsation.

Further, for example, in various small-sized devices such as computer parts these days, it is widely practiced to bond small parts together with an adhesive. The discharge amount of the adhesive used for this bonding also decreases as the parts become smaller,
Strict control is essential. If the amount is less than the predetermined amount, the adhesion will be incomplete, and if the amount is more than the predetermined amount, the protruding adhesive will adversely affect the assembly and the performance. However, pipes are required to have flexibility in terms of workability,
Due to its flexibility, the expansion and contraction of pipes cannot be avoided from a microscopic perspective. Since there is a minute pressure fluctuation on the pipe side, it is extremely difficult to precisely control the discharge amount of the adhesive.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a pipe structure which has flexibility, but does not or does not easily expand or contract even when viewed microscopically.

[0005]

SUMMARY OF THE INVENTION The pipe structure of the present invention has been completed based on the idea that the expansion and contraction of a flexible pipe is suppressed by fluid pressure, and at least one outer peripheral pipe is concentrically provided on the outer periphery of the central pipe. It is characterized in that a fluid-filled space is formed between both pipes, and a fluid is filled in the fluid-filled space. According to this configuration, by applying an appropriate pressure to the fluid in the fluid-filled space, it is possible to suppress micro expansion / contraction (deformation) of the central pipe. As the liquid to be enclosed, water can be used most simply, and other liquids can be used as appropriate.

The center pipe having one end connected to the discharge nozzle has the other end communicated with the liquid pool, and the outer periphery of the liquid pool is connected to the outer peripheral pipe to form a liquid pool surrounding space with the liquid pool. It is possible to provide a pressing means for arranging the flexible body and further for applying a pressure to deform the surrounding flexible body.

In this structure, when pressure is applied to the surrounding flexible body by the pressurizing means, the fluids in the liquid pool surrounding space and the fluid filled space are simultaneously pressurized. Therefore, expansion / contraction (deformation) of the central pipe is suppressed, and at the same time, pressure is exerted on the liquid pool, so that the fluid in the liquid pool can be sent to the central pipe. That is, since it is possible to simultaneously apply pressure to the fluid to be sent out through the central pipe and the fluid that suppresses the deformation of the central pipe, expansion and contraction of the central liquid passage, and a preferable state in which pulsation resulting from this is reliably suppressed Thus, the fluid in the liquid pool can be sent out. As means for applying pressure to the liquid pool surrounding space, either mechanical means or fluid pressure means can be used. Further, a liquid replenishing passage can be connected to the liquid reservoir via a check valve.

[0008]

The present invention will be described below with reference to the illustrated embodiments.
1 and 2 show an embodiment of the pipe structure 10 of the present invention. The pipe structure 10 includes a concentric center pipe 11 and an outer peripheral pipe 12 made of a flexible synthetic resin material, and a closed fluid-filled space 13 having an annular cross section is formed between the pipes. There is. A bulging portion 1 as a pressure adjusting means is provided in a part of the fluid filled space 13.
4 are formed, and the fluid-filled space 13 and the bulging portion 14 are filled with the fluid 15. One end of the center pipe 11 is connected to a discharge nozzle (or injection needle) 16 made of, for example, a metal material, and the other end is connected to a pump 17. The pump 17 is a cylinder 18 in this embodiment.
And a piston 19 fitted to the cylinder pump (syringe). By sliding the piston 19 toward the pipe structure 10, the fluid in the cylinder 18 (for example, a chemical solution or an adhesive) is a central pipe. It is ejected from 11 through the ejection nozzle 16.

The pressure in the fluid-filled space 13 can be adjusted by adjusting the pressure applied to the outside of the bulging portion 14. Then, in a state where an appropriate pressure is applied to the fluid 15 in the fluid-filled space 13, the deformation of the central pipe 11,
That is, since expansion / contraction is suppressed, it is possible to eject the fluid from the ejection nozzle 16 in an amount that exactly corresponds to the movement amount of the piston 19. That is, the central pipe 11 is the fluid 15
Since the deformation is suppressed so that pulsation does not occur so that the cross-sectional area does not change due to the pressure of, the change in the pressure outside the discharge nozzle 16 is not affected and The discharged fluid can be discharged.

Any means for adjusting the pressure applied to the bulging portion 14 may be used. For example, in addition to applying a mechanical pressing force to the bulging portion 14,
Means such as placing the bulging portion 14 in a pressure vessel and adjusting the pressure in the pressure vessel can be used.

FIG. 3 shows an embodiment of a pump according to the present invention, which uses the above pipe structure. This pump includes a liquid pool 21, a surrounding flexible member 22 surrounding the liquid pool 21, and a pressurizing means 23 for the surrounding flexible member 22 in the pipe structure 10.
It is characterized by the addition of. The liquid pool 21 is connected to the end of the center pipe 11 on the opposite side of the discharge nozzle 16, and the surrounding flexible body 22 is connected to the end of the outer peripheral pipe 12 on the same side. A liquid pool surrounding space 24 is formed between the above and. And this liquid pool surrounding space 2
4 and the fluid-filled space 13 are filled with the fluid 15 as in the previous embodiment.

The pressurizing means 23 comprises a fixed container 26 for accommodating the surrounding flexible member 22 and a pressing member 27 in the fixed container 26 which can be brought into contact with and separated from the surrounding flexible member 22. When the surrounding flexible body 22 is pressed by the pressing body 27, the pressure of the fluid 15 filled in the liquid pool surrounding space 24 and the fluid sealing space 13 rises, and the expansion and contraction of the central pipe 11 is suppressed. At the same time, the pressing body 27 causes the liquid pool 21
Since the fluid inside is pushed out to the central pipe 11, the discharge nozzle 1 discharges an amount of fluid exactly corresponding to the movement amount of the pressing body 27.
6 can be discharged.

A liquid replenishment passage 29 is connected to the liquid pool 21 via a check valve 28 so that the fluid from the pressurized liquid supply source 30 can be appropriately replenished to the liquid pool 21.

FIG. 4 shows an embodiment using a fluid pressurizing means as the pressurizing means 23. The pressurizing means 23 accommodates the surrounding flexible body 22 in an airtight container 31.
Via a pressurized air source 32 and a pressure regulating valve 33,
The air pressure is applied. According to this embodiment, the surrounding flexible body 22 can be pressed by the air pressure, and the same effect as that of the previous embodiment can be obtained.

【The invention's effect】

As described above, according to the pipe structure of the present invention, it is possible to obtain a pipe structure which has flexibility, but does not or does not easily expand or contract even when viewed microscopically. Therefore, an extremely small amount of fluid, for example, a chemical solution or an adhesive can be precisely discharged. According to the second aspect, the pressure of the fluid-filled space can be adjusted according to the properties of the central pipe and the fluid flowing through the central pipe.

According to the pump of claims 3 to 5,
A fluid can be discharged from the pipe at the same time while suppressing a change in cross-sectional area due to expansion and contraction of the central pipe. According to the sixth aspect, the liquid can be easily replenished in the liquid pool.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of a pipe structure according to the present invention.

FIG. 2 is a sectional view taken along the line BB of FIG.

FIG. 3 is a vertical sectional view showing an embodiment of a pump according to the present invention.

FIG. 4 is a vertical cross-sectional view showing another example of the pressurizing means of the pump structure of FIG.

[Explanation of symbols]

 10 pipe structure 11 center pipe 12 outer peripheral pipe 13 fluid filled space 14 bulging portion 15 fluid 16 discharge nozzle 17 pump 18 cylinder 19 piston 21 liquid pool 22 surrounding flexible body 23 pressurizing means 24 liquid pool surrounding space 26 fixed container 27 pressing Body 28 Check valve 29 Liquid supply path 30 Pressurized liquid source 31 Closed container 32 Pressurized air source 33 Pressure regulating valve

Claims (6)

[Claims] 1. A central pipe made of a flexible material is concentrically provided with at least one outer peripheral pipe to form a fluid-filled space between the two pipes, and a fluid is filled in the fluid-filled space. A pipe structure characterized by that. 2. The pipe structure according to claim 1, wherein the outer peripheral pipe is provided with means for adjusting the pressure in the fluid-filled space. 3. The center pipe according to claim 1, wherein one end of the central pipe communicates with a flexible liquid pool, and the outer periphery of the liquid pool is connected to the outer peripheral pipe and surrounds the liquid pool. The surrounding flexible body that forms the space is located,
Further, a pump having a pipe structure provided with a pressurizing means for pressurizing and deforming the surrounding flexible body. 4. The pump according to claim 3, wherein the pressurizing means is a mechanical pressurizing means having a piston body for mechanically pressing the surrounding flexible body. 5. The pump according to claim 3, wherein the pressurizing means comprises a pipe structure which is a fluid pressurizing means for exerting a fluid pressure on the outer circumference of the surrounding flexible body. 6. The pump according to claim 3, wherein the liquid reservoir has a pipe structure in which a liquid supply path is connected via a check valve.