JP2011226354A - Diaphragm pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a diaphragm pump highly stabilized in a flow rate, which can cope with various conditions, and having high durability in regard to a pump including a flow passage formed of a cylindrical diaphragm.SOLUTION: A change in thickness of the diaphragm is avoided by using a metal as a material for the cylindrical diaphragm and forming a cross section thereof into an elliptic shape. Concentration of force is prevented by giving orientation to the extension and shrinkage of the diaphragm to complete the restoration. Thereby, a flow rate is stabilized, and pressure resistance and durability are improved.

Description

  The present invention relates to a pump using a diaphragm that isolates a wetted part in contact with a fluid and other parts in a system that generates a fluid having a constant flow rate or high pressure, such as a reciprocating pump.

  Conventionally, pumps have used seal materials such as O-rings to isolate the wetted parts from other parts. However, in any seal material, leakage from the sliding portion is inevitable, and in order to achieve complete leakage-freeness, there is no other way but to use a diaphragm. There are many pumps that use a diaphragm. Generally, the pump chamber in which the fluid flows and the working chamber in which the plunger and the like operate are divided by the diaphragm, and the pressure on the working chamber side is fluctuated, which is transmitted to the diaphragm through the working fluid, As the diaphragm expands and contracts, the structure serves as a pump. (Patent Document 1) In addition, a diaphragm is not used as a simple film, but is used such that a flow path is formed by a cylindrical diaphragm (hereinafter referred to as a tube diaphragm). (Patent Document 2)

Public Utility Sho 55-88088 JP 2009-47090 PR

  However, the conventional diaphragm uses an elastic body such as rubber or a resin as a material, but both are weak against pressure and are compressed under pressure.

  Therefore, as in Patent Document 2, when the tube diaphragm is used as a flow path, the tube diaphragm receives pressure from inside and outside by the working fluid for transmitting the pressure of the carrier fluid and the pressure of the blanker, etc. The internal volume of the flow path is changed by being compressed. As a result, the flow rate easily changes due to pressure fluctuations, etc., so it was not suitable for a metering pump that requires precision.

  In addition, when the shape of the tube diaphragm is a cylinder having a general cross-section, there is a problem in that one point that is weak in structure is deformed by the pressure, so that the pressure is more easily applied and the tube frame is easily broken. It was.

  An object of the present invention is to solve the problems of the conventional diaphragm pump as described above, and to provide a diaphragm pump having higher versatility and a stable flow rate and having high durability.

  In order to solve the above-mentioned problems, the present invention is characterized in that a metal material is used as a material for a tube frame forming a flow path. It is a well-known fact that a metal material is harder to be compressed by pressure than an elastic body such as rubber, so that it can withstand use under high pressure and is not easily affected by pressure fluctuations.

  As the metal material used at this time, a material excellent in corrosion resistance and chemical resistance such as stainless steel is desirable, and an amorphous metal such as metal glass is particularly desirable.

  Amorphous metal is a metal that does not have a crystal structure. Therefore, there are some that have high corrosion resistance and chemical resistance as compared with ordinary metal materials in addition to being supple and having high strength. Therefore, it is very useful as a diaphragm material for a quantitative pump.

  In the present invention, the shape of the tube frame is not a simple cylinder, but is characterized in that the cross section has an elliptical shape and / or has a change in thickness.

  By adopting the structure as described above, it is possible to intentionally create a deformable part such as an elliptical long diameter part or a thin part. By taking such a portion that is easily deformed, it is possible to prevent the pressure applied to the tube frame from concentrating on one pole and to avoid destruction. Further, the portion facing the blanker can be made thick so that it can withstand the load caused by the kinetic energy of the working fluid.

Further, since the difference in thickness is provided, the tube frame has a spring-like property, and even if it is directly pressed by a blanker or the like, its shape can be easily restored by its elasticity. Therefore, the pump can be operated without using a fluid for mediating pressure.

  According to the diaphragm pump of the present invention, a pump that can be used under a wide range of conditions such as pressure and fluid properties, which is impossible with a conventional diaphragm pump, and has high quantitativeness, but does not cause fluid leakage, is provided. can do. Therefore, it can be expected to be used for line mixing and precision coating of various types of liquids that require flow rate accuracy.

  DESCRIPTION OF EMBODIMENTS Embodiments of the present invention will be described below with reference to the accompanying drawings. However, the embodiments are merely examples and do not limit the scope of the present invention.

  FIG. 1 is an internal view showing a schematic configuration around a pump head portion and a tube diaphragm of a diaphragm pump according to the present invention. The pump housing 1 includes a blanker 2, a tube diaphragm fixing portion 3, a fluid outlet portion 4, a fluid introduction portion 5, a working space 6, a tube diaphragm 7, a check valve 8, and other working fluid introduction portions and working fluid lead portions that are not shown. Is provided.

  The working space 6 is filled with a working fluid, and the reciprocating motion of the blanker 2 causes the working fluid and the pressure inside the tube frame 7 to fluctuate therethrough. Thereby, the carrier fluid is drawn into the tube frame from the fluid introduction part 5 as the pressure decreases, and is discharged from the fluid outlet part 4 as the pressure increases.

  Further, in FIG. 1, the structure is such that the plunger and the working fluid are in direct contact, but a diaphragm may be provided between the plunger and the working space. Furthermore, the working space may not be filled with the working fluid, and the flanger may directly press the tube frame.

  The tube frame 7 is fixed at both ends by the tube frame fixing unit 3. An example of the material of the tube frame 7 is a stainless alloy or the like, and it is desirable that the material is as flexible as possible, yet strong against compression, and excellent in corrosion resistance and chemical resistance.

2 is a cross-sectional view taken along line AA in FIG. As shown in the figure, a relatively thick surface 9 and a relatively thin surface 10 exist on the tube frame wall surface. By adopting such a structure, if a pressure is applied during the pump operation, the widely taken thin surface 10 is deformed, and the pressure acting on the tube frame 7 is prevented from being concentrated. In addition, in FIG. 2, although the cross section is made into the shape of an ellipse, various shapes, such as a tear suitable form, can be considered.

It is the figure which showed the pump head part internal structure of the diaphragm pump in this invention. It is an AA line sectional view of Drawing 1 in a first embodiment of the present invention. It is the sectional view on the AA line of FIG. 1 in 2nd embodiment of this invention.

DESCRIPTION OF SYMBOLS 1 Pump housing 2 Blanker 3 Tube frame fixing | fixed part 4 Fluid lead-out part 5 Fluid introducing | transducing part 6 Actuation space 7 Tube frame 8 Check valve 9 Tube frame thick part 10 Tube frame thin part

Claims (4)

In a pump using a diaphragm that isolates the wetted part and other parts that are in contact with fluid, the diaphragm is formed in a cylindrical shape, and the difference in the cross-sectional circumference of the thickness of the cylindrical diaphragm is used as a flow path. A diaphragm pump characterized by being used.
A pump using a diaphragm that isolates the wetted part and other parts that are in contact with fluid, and the diaphragm is formed into a cylindrical shape and the cross section is formed into an elliptical shape. .
The diaphragm pump according to claim 1 or 2, wherein a metal material is used as a material of the cylindrical diaphragm used as the flow path.
The diaphragm pump according to claim 3, wherein the metal material is an amorphous metal.