JPH0729035B2 - Pressure balancer - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a pressure balancer, and more particularly to a zero pressure difference between two gases, which is suitable for achieving long-term stability of the mixing ratio of a gas mixing device. It relates to a pressure balancer that keeps

[Conventional technology]

In a blood gas analyzer, it is necessary to produce two or more kinds of calibration standard solutions from a known aqueous solution by utilizing the partial pressures of carbon dioxide and an enzyme inside the apparatus. For this, a mixed gas of carbon dioxide gas, carbon and nitrogen of known composition, which is generally filled in a cylinder, is saturated with an aqueous solution and used. U.S. Patent No. 34
No. 64434 (hereinafter referred to as known example A) improves this point and discloses a gas mixing device in which carbon dioxide is supplied from a cylinder in a pure gas state and oxygen and nitrogen are mixed gas using air. There is. The feature of the known example A is that a relief type differential pressure control valve is used, and the pressure of air higher than carbon dioxide gas is released to the atmosphere through a relief port to make both pressures equal. Especially.
Another feature is that the relief port is realized with a relatively simple structure by supplying the air pressure at a pressure of about 0.1 kgf / cm ² .

Next, there is Japanese Patent Application Laid-Open No. 59-110968 (hereinafter referred to as a known example B) as a conventional technique which is not a function but an approximation as a configuration. In this known example B, two fluids are mixed so that they do not mix with each other.
It is characterized by having one or more seals between the fluids and returning the fluid from the escape channel to the supply tank for reuse.

[Problems to be solved by the invention]

In the above-mentioned publicly known example A, no consideration is given to the point of gas loss, and in order to maintain the pressure equilibrium between air and carbon dioxide, air is extracted from the relief port. Therefore, it is necessary to supply more air than necessary, and it is necessary to increase the capacity of the pump and the air filter by that amount. Further, no consideration has been given to the input pressure of the gas mixer for air and carbon dioxide gas, and there is a problem that the air side operates only when the input pressure is higher than the carbon dioxide gas side.

In the known example B, one or more sealing bodies that separate the two fluids are used so that the two fluids do not mix with each other, but no consideration is given to the point of friction resistance, and the sealing body has a cylindrical shape. Due to the frictional resistance when sliding in the hole, there is a problem that it does not operate with a slight differential pressure. Further, no consideration has been given to the point of fluid loss, and there has been a problem that a large amount of fluid is wasted from the escape passage in order to reach pressure equilibrium.

The object of the present invention is to solve the above-mentioned problems, and it is possible to achieve a pressure balance with a very simple structure without loss of fluid and whichever of the two flow paths has a higher pressure. In addition, it is to provide a pressure balancer that operates even with an extremely small differential pressure.

[Means for solving problems]

In order to achieve the above object, the present invention configures a pressure balancer as follows. The reference numerals given to the components of the invention described below are the reference numerals of the embodiments shown in FIGS. 1 and 2 for the sake of easy understanding of the invention.

That is, the present invention corresponds to the two independent gas flow paths 50 and 51, and the first gas chamber 1 and the second gas chamber 1 for adjusting the pressure of the gas flowing out to the first gas flow path 50 among them. Two chambers, a second gas chamber 11 and a second gas chamber 11 for adjusting the pressure of the gas flowing out to the flow path 51, are airtightly arranged adjacent to each other inside the one casing 60 via the diaphragm 20, and the first and second gas chambers are arranged. A structure in which the diaphragm 20 responds to the differential pressure of 1,11 is configured, and the first gas chamber 1 includes a gas inflow port 4 for introducing a gas to be pressure-controlled on one side and the first gas flow path. The second gas chamber 11 has a gas outlet 6 connected to 50, and is connected to the other gas inlet 14 for introducing the gas whose pressure is to be adjusted and the second gas passage 51. And a gas outlet port 16 of each of the first and second gas chambers 1 and 11 is located at the center of the diaphragm 20. A spindle-shaped fluid resistance element 3, which is arranged on the axis and is oriented to be located at each of the gas inlets 4 and 14 of the first and second gas chambers 1 and 11 on both sides of the center of the diaphragm 20, The rods 2 and 12 with 13 are fixedly arranged, and the gas inlets 4 and 14 of the first and second gas chambers 1 and 11 are fixed.
When the fluid resistance elements 3 and 13 are interlocked with the differential pressure response of the diaphragm 20, the fluid resistance elements 3 and 13 are
Of the first gas chamber 1 is provided with annular convex portions 5 and 15 having surfaces that change the fluid resistance values of the gas inlets 4 and 14 themselves in cooperation with the displacement of the second gas. When the pressure becomes higher than the pressure in the chamber 11, the convex portion 15 of the gas inflow port 14 of the second gas chamber 11 responds to the movement of the diaphragm 20 toward the second gas chamber 11 side due to the differential pressure at that time. Of the second gas chamber 11 reduces the fluid resistance value of the gas inflow port 14 of the second gas chamber 11, and the convex portion 5 of the gas inflow port 4 of the first gas chamber 1 and the corresponding The fluid resistance value of the gas inlet 4 of the first gas chamber 1 is increased by narrowing the space between the fluid resistance element 3 and the fluid resistance element 3, and conversely, the pressure of the second gas chamber 11 is equal to that of the first gas chamber 1. When the pressure becomes higher than the pressure, the gas inlet of the first gas chamber 1 accompanies the reaction of the diaphragm 20 to the first gas chamber 1 side due to the differential pressure at that time. The corresponding fluid resistance element 3 is moved away from the convex portion 5 to reduce the fluid resistance value of the gas inlet port 4 of the first gas chamber 1 and to reduce the fluid resistance value of the gas inlet port 14 of the second gas chamber 11. The gas inlet of the second gas chamber 11 is narrowed by narrowing the gap between the convex portion 15 and the fluid resistance element 13 corresponding thereto.
The fluid resistance values of 14 are set to be large, and the first and second gas chambers 1 and 11 are automatically adjusted by these fluid resistance values.
It is characterized in that the gas pressures from the above to the first and second gas flow paths 50 and 51 are set to the same pressure.

[Action]

This pressure balancer operates as follows. When the pressures of the two chambers (the first gas chamber 1 and the second gas chamber 11) are equal, no tension acts on the diaphragm 20 in equilibrium, and the fluid resistance elements 3 and 13 and the gas inlets 4 and 14 are in equilibrium. The distance between the convex portions 5 and 15 and the fluid resistance is the same for both gases.

Here, due to the fluctuation of the gas pressure, the pressure of the first gas (the gas flowing in the first gas flow passage 50) is higher than the pressure of the second gas (the gas flowing in the second gas flow passage 51). Assuming that the pressure in the first gas chamber 1 becomes higher than the pressure in the second gas chamber 11, the diaphragm 20 is
Is displaced toward. Along with this, the fluid resistance elements 3 and 13 fixedly arranged on both sides of the diaphragm 20 are displaced (moved) toward the second gas chamber 11. The fluid resistance elements 3 and 13 are spindle-shaped, and here, due to the above displacement, the fluid resistance element 13 moves away from the convex portion 15 of the second gas inlet port 14 and the convex portion 15 corresponding to the fluid resistance element 13 is formed. And the fluid resistance value of the second gas inlet port 14 decreases, while the fluid resistance element 3 approaches the convex portion 5 of the first gull inlet port 4 and the first gas inlet port 4 The fluid resistance value of becomes large.

As a result, the pressure in the first gas chamber 1 drops, while the second gas chamber 1
Pressure in the gas chamber 11 rises, and the gas pressures in these two chambers 1 and 11 converge so as to be the same pressure, and the diaphragm 20 also moves to the first position.
Returning to the gas chamber 1, the first gas chamber 1 and the second gas chamber 11
As a result, the pressure equilibrium of the first and second gas flow paths 50 and 51 is maintained.

The same operation is performed when the pressure of the second gas becomes higher than the pressure of the first gas (in this case, the diaphragm 20
The fluid resistance elements 3 and 13 operate in the opposite manner to the operation when the first gas pressure becomes higher than the second gas pressure, but the operating principle is the same), and the pressure balance is maintained.

〔Example〕

Hereinafter, an embodiment of the present invention will be described in detail with reference to FIGS.

FIG. 1 is a sectional view showing an embodiment of the pressure balancer of the present invention.

The pressure balancer includes a first gas chamber (hereinafter,
A first gas chamber) 1, a second gas chamber (hereinafter, simply referred to as a second chamber) 11, fluid resistance element supporting portions (rods) 2, 12, a spindle-shaped portion 3 serving as a fluid resistance element , 13, a first gas inlet 4, a second gas inlet 14, an annular protrusion 5 of the inlet 4, an annular protrusion 15 of the inlet 14, a first gas outlet 6, It comprises a second gas outlet 16, a diaphragm 20, a connecting portion 21 between the diaphragm 20 and the fluid resistance elements 3 and 13, case elements 7 and 17 which form a casing 60, and the like.

More specifically, the diaphragm 20 is sandwiched between the case elements 7 and 17 that form one casing 60, and these case elements 7 and 17 are coupled by a set screw 22, so that
Corresponding to the two independent gas flow passages 50 and 51 (see FIG. 2), a first chamber 1 and a second gas flow passage for adjusting the pressure of the gas flowing into the first gas flow passage 50 among them. Two chambers, a second chamber 11 and a second chamber 11 for adjusting the pressure of the gas flowing to 51, are airtightly adjacent to each other inside a casing 60 via a diaphragm 20, and the difference between the first and second chambers 1 and 11 is provided. A mechanism in which the diaphragm 20 responds to pressure is constructed.

The first chamber 1 has a gas inflow port 4 and a gas outflow port 6, and the gas inflow port 4 is connected to a gas inflow pipe 51 '(see FIG. 2) for introducing the first gas to be pressure-controlled. The gas outlet 6 is connected to the first gas flow path 50 whose pressure is to be adjusted. The second chamber 11 has a gas inflow port 14 and a gas outflow port 16, and the gas inflow port 14 is a gas inflow pipe for introducing the second gas to be pressure-controlled.
51 '(see FIG. 2), and the gas outlet 16 is connected to the second gas flow path 51 to be pressure-controlled. Gas inlet 4,
14 are symmetrically arranged via the diaphragm 20 on the same axis as the center of the diaphragm 20.

The supporting portions 2 and 12 of the fluid resistance elements 3 and 13 are firmly and airtightly fixed to both sides of the center of the diaphragm 20 via the joint portion 21.

The fluid resistance element (spindle-shaped portion) 3, 13 gradually increases in outer diameter as it moves away from the diaphragm 20, and the convex portion 5, 15 provided on the gas inlet 4, 14 side at the maximum diameter portion.
Is designed to be larger than the inner diameter of the fluid resistance element 3, the fluid resistance element 3 being oriented at the gas inlet 4, and the fluid resistance element 13 being oriented at the gas inlet 14.

In this way, each fluid resistance element 3, 13 is connected to the diaphragm 20.
These fluid resistance elements 3, when interlocked with the differential pressure response of
The displacement of 13 and the convex portions 5 and 15 cooperate to change the fluid resistance value of each gas inlet port 4 and 14 itself.

The surfaces of the convex portions 5 and 15 and the spindle-shaped portions 3 and 13 are processed very smoothly, and the fluid resistance element, that is, the spindle-shaped portions 3 and 13 and the supporting portions 2 and 12 are made of light metal or plastic. O-rings or the like are used for the convex portions 5 and 15. Further, the diaphragm 20 is airtightly attached to the main bodies 7, 17 with a set screw 22. The diaphragm 20 may be a flat diaphragm or a grooved diaphragm.

The operation of this pressure balancer is located at the center of the main bodies 7 and 17, as shown in the figure, because the diaphragm 20 is not tensioned if the pressures in the first chamber 1 and the second chamber 11 are equal. Here, if the pressure of the first gas is higher than the pressure of the second gas, the pressure of the first chamber 1 is equal to that of the second chamber 11.
Therefore, the diaphragm 20 is displaced to the right in the figure (close to the second chamber 11). Along with this, the distance between the spindle-shaped portion 3 and the convex portion 5 is narrowed, and the fluid resistance value is increased. On the contrary, the distance between the spindle-shaped portion 13 and the convex portion 15 is widened, and the fluid resistance value is reduced. That is, the pressure in the first chamber 1 decreases, the pressure in the second chamber 11 increases, and the pressures in the two chambers 1 and 11 are made equal. On the contrary, when the pressure of the second gas becomes higher than that of the first gas, the diaphragm
20 is displaced in the left direction (close to the first chamber 1) in the figure, and the pressure in the two chambers 1 and 11 becomes equal due to the change in the fluid resistance value accompanying the displacement.

FIG. 2 is a schematic view showing an embodiment in which the pressure balancer according to the present invention is installed in a gas mixer for mixing two gases.
The gas mixer includes a first gas supply port 30, a second gas supply port 31, a pressure reducing valve 32 provided in the first gas inflow pipe 50 ', a second gas supply port 50'.
Pressure reducing valve 33 provided in the gas inflow pipe 51 ′ of the same, a pressure balancer 34 having the same configuration as in FIG. 1, and a flow diverter branched from the first gas flow path 50.
35, 36, flow dividers 37, 38 branched from the second gas flow path 51, one mixed gas outlet 39, and the other mixed gas outlet 40 are connected as shown. Here, the gases of the flow divider 35 and the flow divider 37 are mixed, and the gases of the flow divider 36 and the flow divider 38 are mixed. That is, after the first and second chambers 1 and 11,
A gas mixing section for mixing the gases in the first and second gas flow paths 50, 51 is arranged. The pressure reducing valves 32 and 33 are set so that their secondary pressures are constant, but they do not always become equal pressure due to variations in the primary pressure. Therefore, as shown in the figure, a pressure balancer 34 is installed between the secondary pressures, and the former stage of the flow dividers 35, 36, 37, 38, that is, the first gas flow path 50 and the first chamber 1, Second
If the pressures of the gas flow path 51 and the second chamber 11 are made equal, the accuracy of the gas components at the mixed gas outlets 39, 40 is significantly improved.

FIG. 3 is a recording diagram in which the secondary pressures of the two pressure reducing valves 32, 33 of the gas mixer are simultaneously measured. FIG. 3 (a) shows a pressure balancer 34.
Before installation, (b) is an example of recording after installation of the pressure balancer. The gas is for mixing air and carbon dioxide, and the pressure reducing valve 32,3
For both 3, the secondary pressure is set to 0.2 kg / cm ² . Since air is supplied from the air compressor to the gas mixer,
ON is the time when the power of the compressor is turned on and the air pressure rises. Since air is used to manufacture the mixed gas, the air pressure gradually decreases after the compressor is turned on. Considering the pen difference of the recorder, in (a), the air pressure and carbon dioxide gas pressure fluctuate separately, but in the case of (b) after setting the pressure balancer 34, both gas pressures are changed. Is always kept at the same pressure. As a result, as shown in Table 1, the carbon dioxide concentration of the mixed gas is about a coefficient of variation CV when the pressure balancer 34 is installed.
The accuracy is significantly improved to 1/6.

[Effects of the Invention] As described above, according to the present invention, it is possible to equalize the pressure with two independent gas flow paths to be pressure-controlled by the action of the fluid resistance element interlocked with the diaphragm. It has a very simple structure, there is no loss of fluid, and pressure balance can be achieved regardless of which pressure of the two flow paths is high.
Moreover, it has the effect of operating even with a very small differential pressure.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the pressure balancer of the present invention,
FIG. 2 is a schematic view showing an embodiment in which the pressure balancer according to the present invention is installed in a gas mixer that mixes two gases, and FIG. 3 is a recording diagram in which secondary pressures of two pressure reducing valves of the gas mixer are simultaneously measured. Is. 1,11 …… Room, 2,12 …… Support part of fluid resistance element, 3,13 ……
Spindle-shaped part of fluid resistance element, 4,14 …… Inlet, 5,15 ……
Convex part, 6,16 …… Outlet, 20 …… Diaphragm, 21 …… Coupling part.

Claims (2)

[Claims] 1. A gas flowing out to a first gas chamber and a gas flowing out to a second gas flow passage for adjusting the pressure of the gas flowing out to the first gas flow passage corresponding to two independent gas flow passages. Two chambers, a second gas chamber and a second gas chamber for adjusting the pressure, are airtightly adjacent to each other inside a casing through a diaphragm,
The first gas chamber constitutes a mechanism in which the diaphragm responds to the pressure difference between the first gas chamber and the second gas chamber, and the first gas chamber includes a gas inlet for introducing the gas to be pressure-controlled on one side and the first gas flow. A gas outlet connected to a channel, and the second gas chamber has a gas inlet for introducing another gas whose pressure is to be adjusted and a gas outlet connected to the second gas passage. And the gas inlets of the first and second gas chambers are respectively arranged on the same axis as the center of the diaphragm, and both sides of the center of the diaphragm include the gas chambers of the first and second gas chambers. A rod with a spindle-shaped fluid resistance element oriented so as to be positioned at each gas inlet is fixedly arranged, and each fluid resistance element is provided at each gas inlet of the first and second gas chambers. The displacement of these fluid resistance elements is coordinated with the differential pressure response of Then, an annular convex portion having a surface that changes the fluid resistance value of each gas inlet is provided, and when the pressure of the first gas chamber becomes higher than the pressure of the second gas chamber, the difference in pressure at that time causes Along with the reaction of the diaphragm toward the second gas chamber, the fluid resistance element corresponding to the convex portion of the gas inlet of the second gas chamber moves away from the convex portion of the gas inlet of the second gas chamber. The fluid resistance value is reduced, and the convex portion of the gas inflow port of the first gas chamber and the fluid resistance element corresponding thereto are narrowed to reduce the fluid resistance value of the gas inflow port of the first gas chamber. When the pressure in the second gas chamber becomes higher than the pressure in the first gas chamber, conversely, when the pressure in the second gas chamber becomes higher than the pressure in the first gas chamber, the differential pressure at that time causes the first gas chamber to react with the first gas chamber. When the fluid resistance element corresponding to the convex portion of the gas inlet of the gas chamber moves away from the convex portion, Of the second gas chamber, the fluid resistance value of the gas inlet of the second gas chamber is reduced, and the gap between the convex portion of the gas inlet of the second gas chamber and the corresponding fluid resistance element is narrowed. The fluid resistance value at the gas inlet is set to be large, and the fluid resistance values are automatically adjusted from the first and second gas chambers to the first and second gas chambers.
A pressure balancer characterized in that the gas pressures up to the second gas flow path are set to be equal to each other. 2. A gas pressure reducing valve is connected to a front stage of the first and second gas chambers via first and second gas inflow pipes connected to the gas inlets, respectively. 2. The pressure balancer according to claim 1, wherein a gas mixing section for mixing the gases in the first and second gas passages is arranged at the subsequent stage of the first and second gas chambers.