Ejector

Abstract

To provide an ejector that can prevent backflow of working fluid into the gas supply system. [Solution] The ejector 1 has an orifice section 13, a reservoir section 18, and a suction groove 19. Working fluid flows through the orifice section 13. The reservoir section 18 is formed around the orifice section 13 and gas is drawn in through it. The suction groove 19 is formed around the orifice section 13 and supplies the gas from the reservoir section 18 to the orifice section 13. The groove width of the suction groove 19 is set to 100 μm or less.

Description

Technical Field

[0001] The present invention relates to an ejector into which a gas is introduced together with a working fluid.

Background Art

[0002] As an ozone water generator that injects ozone gas as a gas into a flow of a working fluid such as water to generate ozone water as a gas-dissolved liquid, for example, an ejector-type one such as Patent Documents 1 and 2 can be mentioned.

[0003] In an ejector-type ozone water generator, when a negative pressure occurs in an ozone generator connected to the suction port of the ejector, the probability of a decrease in the ozone gas generation ability and a defect in the ozone generator increases. Therefore, the ozone water generator of Patent Document 1 provides an orifice between the ozone generator and the ejector to keep the ozone gas generation unit of the ozone generator at a positive pressure, and supplies ozone gas to the ejector under the same pressure.

[0004] Further, the ozone water supply system of Patent Document 2 includes a supply line of ozone water, a circulation line of ozone water, an ozone concentration sensor, and a controller for the generated ozone concentration of an ozone generator, and controls so that there is no fluctuation in the ozone concentration in the discharge of ozone water to the supply line or the like. The ozone gas as a raw material for ozone water is generated by a discharge-type ozonizer that uses oxygen as a main raw material and generates ozone gas by discharge, and the supply pressure is normal pressure or higher.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] The conventional technology described above generates ozonated water by mixing ozone gas and water using a gas-liquid mixing device such as an ejector. The supply pressure of the ozone gas in this process is considered to be positive pressure.

[0007] On the other hand, some ozonizers, which generate ozone gas, maintain a negative pressure inside the device to suppress the self-decomposition of highly concentrated ozone gas.

[0008] In the conventional ozone water generator described above, if an ozonizer that maintains ozone gas from the ozone supply system under negative pressure is applied, if sufficient suction pressure cannot be obtained due to abnormalities in the supply water temperature or pump, water may flow back from the ozone gas intake of the ejector and back into the ozone gas supply system. This backflowing water may then enter the ozone gas flow meter, valves, etc. in the ozone supply system, potentially causing malfunction or failure of the supply system.

[0009] In view of the above circumstances, the present invention aims to provide an ejector that can prevent backflow of working fluid into a gas supply system. [Means for solving the problem]

[0010] Therefore, one aspect of the present invention is an ejector having an orifice portion through which a working fluid flows, a storage portion formed around the orifice portion and into which gas is drawn in, and a suction groove formed around the orifice portion and having a groove width of 100 μm or less for supplying the gas from the storage portion to the orifice portion.

[0011] One aspect of the present invention is an ejector enclosed in a tank through which a gas is introduced by suction, comprising an orifice portion through which a working fluid flows, and a suction groove formed around the orifice portion, with a groove width of 100 μm or less, for supplying the gas in the tank to the orifice portion.

[0012] In one aspect of the present invention, the ejector is formed such that the suction groove is at an acute angle with respect to the flow direction of the working fluid in the orifice.

[0013] In one aspect of the present invention, the ejector is formed such that a plurality of suction grooves are arranged in the direction of the flow of the working fluid in the orifice portion.

[0014] In one aspect of the present invention, in the ejector, the suction grooves are formed in a plurality of directions radially from the orifice portion in the orifice portion. [Effects of the Invention]

[0015] According to the present invention described above, it is possible to prevent backflow of the working fluid into the gas supply system in the ejector. [Brief explanation of the drawing]

[0016] [Figure 1] (a) A schematic diagram of an ejector according to Embodiment 1, which is one aspect of the present invention, and (b) a cross-sectional view aa of the ejector. [Figure 2] A schematic diagram of an ejector according to Embodiment 2, which is one aspect of the present invention. [Figure 3] A schematic diagram of the ejector according to Embodiment 3, which is one aspect of the present invention. [Modes for carrying out the invention]

[0017] Embodiments of the present invention will be described below with reference to the drawings.

[0018] [Embodiment 1] The ejector 1 of Embodiment 1, shown in Figure 1, which is one aspect of the present invention, in order to generate a gas-dissolved liquid by injecting gas as a gas into the flow of a working fluid, suppresses the backflow of fluid into the gas supply system when sufficient gas suction pressure cannot be obtained, thereby preventing malfunction or failure of the gas supply system.

[0019] In other words, the ejector 1 has an inlet 11, a communication section 12, an orifice section 13, a communication section 14, a flow straightening section 15, a communication section 16, a discharge section 17, a storage section 18, and a suction groove 19.

[0020] The inflow portion 11 is composed of a straight cylindrical flow path into which the working fluid is introduced.

[0021] The communication portion 12 is composed of a tapered flow path with a decreasing inner diameter that connects the inflow portion 11 and the orifice portion 13 having a smaller diameter than the inflow portion 11, and supplies the working fluid from the inflow portion 11 to the orifice portion 13.

[0022] The orifice portion 13 is composed of an extremely thin straight cylindrical flow path that connects the communication portion 12 and the communication portion 14. The working fluid supplied from the inflow portion 11 via the communication portion 12 flows through it, and gas is suction-introduced from the storage portion 18 via the suction groove 19.

[0023] The communication portion 14 is composed of a tapered flow path with an increasing inner diameter that connects the orifice portion 13 and the rectifying portion 15 having a larger diameter than the orifice portion 13, and supplies the gas-dissolved liquid from the orifice portion 13 to the rectifying portion 15.

[0024] The rectifying portion 15 is composed of a straight cylindrical flow path that connects the communication portion 14 and the communication portion 16, rectifies the gas-dissolved liquid supplied from the orifice portion 13 via the communication portion 14, and supplies it to the communication portion 16.

[0025] The communication portion 16 is composed of a tapered flow path with an increasing inner diameter that connects the rectifying portion 15 and the discharge portion 17 having a larger diameter than the rectifying portion 15, and supplies the gas-dissolved liquid from the rectifying portion 15 to the discharge portion 17.

[0026] The discharge portion 17 is composed of a straight cylindrical flow path that discharges the gas-dissolved liquid from the communication portion 16.

[0027] As shown in Fig. (b) of the same figure, the storage portion 18 is formed coaxially with the orifice portion 13 around the orifice portion 13, and stores the gas supplied under reduced pressure from the gas supply system via the suction pipe 10.

[0028] The gas supply system of this embodiment is intended for the suction of gas supplied at a pressure equal to or greater than the pressure generated by the suction force produced by the ejector 1, and encompasses gas supply systems under reduced pressure. Examples of such gas supply systems include gas supply systems below atmospheric pressure. More specifically, examples include well-known ozone gas supply systems that supply ozone gas with an ozone concentration of 50% by volume or more and an oxygen concentration of less than 50% by volume. In this case, the total pressure of the ozone gas becomes a reduced pressure state of, for example, 60 kPa (abs) or less (i.e., a state where the ozone partial pressure is 30 kPa (abs) or less).

[0029] The suction groove 19 is formed around the orifice portion 13 at an acute angle to the flow direction of the working fluid in the orifice portion 13, and consists of an annular slit that supplies the gas stored in the reservoir portion 18 to the orifice portion 13. The groove width of this suction groove 19 is set to 100 μm or less in order to minimize leakage of the working fluid.

[0030] Furthermore, the suction grooves 19 may be formed so that multiple grooves are arranged in the flow direction of the orifice section 13. This makes it possible to increase the amount of gas suction while preventing backflow of the working fluid into the reservoir section 18. In addition, multiple suction grooves 19 may be formed radially from the orifice section 13.

[0031] The effects of the ejector 1 of this embodiment will be explained with reference to Figure 1. Here, the working fluid is water, the gas is the ozone gas, and the dissolved liquid gas is ozonated water. In particular, an example will be described in which ozonated water with an ozone concentration of 200 ppm or higher is stably supplied.

[0032] Water introduced into the inlet 11 of ejector 1 is discharged from the outlet 17 via the communication section 12, orifice section 13, communication section 14, flow straightening section 15, and communication section 16. Here, the water that has flowed through the inlet 11 has its flow path narrowed in the communication section 12, increasing its flow velocity and rapidly decreasing its pressure before being supplied to the orifice section 13. The water introduced into the orifice section 13 has an increased flow velocity, and the flow path of the orifice section 13 becomes negatively pressurized. Furthermore, in the orifice section 13, ozone gas supplied from the outside at reduced pressure is drawn in via the suction pipe 10, storage section 18, and suction groove 19, generating ozonated water which is supplied to the flow straightening section 15 via the communication section 14. The ozonated water straightened in the flow straightening section 15 is then discharged from the outlet 17 via the communication section 16.

[0033] According to the ejector 1 of this embodiment, since a reservoir 18 and a suction groove 19 are formed around the orifice 13, the gas supplied under reduced pressure via the suction pipe 10 can come into contact with and mix with the working fluid from the entire circumference of the orifice 13, allowing a large amount of gas to be dissolved in the working fluid. In particular, by setting the groove width of the suction groove 19 to 100 μm or less, even if the flow velocity of the working fluid decreases or the working fluid stops, the suction groove 19 is sealed by the surface tension of the working fluid, preventing or reducing the intrusion of the working fluid into the suction pipe 10.

[0034] Furthermore, because the suction groove 19 is positioned at an acute angle to the flow direction of the working fluid flowing through the orifice 13, a large contact area with the working fluid can be secured, thereby increasing the gas dissolution efficiency in the working fluid.

[0035] In conventional ejectors as exemplified in Patent Documents 1 and 2, if sufficient suction pressure cannot be obtained due to the temperature of the working fluid or a malfunction of the pump, the working fluid flows back out of the gas intake of the ejector and enters the gas supply system. This transferred working fluid can then enter gas flow meters, valves, etc., which can cause malfunctions or failures.

[0036] In contrast, according to the ejector 1 of this embodiment, since a suction groove 19 is formed around the orifice portion 13, even if the flow velocity of the working fluid decreases or the working fluid stops, it is possible to prevent or reduce the intrusion of the working fluid into the gas supply system including the suction pipe 10.

[0037] Therefore, even if the working fluid velocity becomes insufficient for some reason, causing a decrease in the suction force of the ejector 1 and the working fluid pressure to exceed the gas supply pressure, it is possible to prevent the working fluid from flowing back into the gas supply system from the gas intake of the ejector 1 and causing a malfunction. This prevents malfunctions and failures of the gas supply system.

[0038] [Embodiments 2, 3] The ejector 1 of Embodiment 2 shown in Figure 2 is enclosed within the tank 2, which stores the gas supplied under reduced pressure from the gas supply system, by passing through the tank 2 in an airtight manner.

[0039] The ejector 1 has the same configuration as in Embodiment 1, except that a suction groove 19 with a groove width of 100 μm or less is formed around the orifice portion 13, perpendicular to the flow direction of the working fluid in the orifice portion 13, for supplying the gas in the tank 2 to the orifice portion 13.

[0040] Tank 2 is formed into any shape at the site where the ejector 1 of this embodiment is installed. The arrangement of the ejector 1 in Tank 2 can also be set to a horizontal or vertical arrangement as appropriate to the site.

[0041] Furthermore, an inlet pipe 21 is connected to the top of the tank 2 to introduce gas supplied under reduced pressure from the gas supply system, and a discharge pipe 22 is connected to the bottom of the tank 2 to discharge the working fluid that has flowed back from the suction groove 19 of the ejector 1 as needed. In addition, a valve V is installed in this discharge pipe 22 to discharge the working fluid accumulated in the tank 2 as needed.

[0042] As is clear from the above configuration, the ejector 1 of this embodiment provides the same effects as in Embodiment 1. In particular, in this embodiment, the ejector 1 penetrates the tank 2 and is enclosed within it, so that both ends of the ejector 1 protrude from the tank 2, while the suction portion (suction groove 19) of the ejector 1 is contained within the tank 2. Furthermore, since the suction groove 19 of the ejector 1 is formed to surround the entire circumference of the orifice portion 13, it is possible to draw in gas from all directions within the tank 2, and a large amount of gas can be taken in. Moreover, if the working fluid flows back from the suction groove 19 of the ejector 1, it is stored in the tank 2. The working fluid stored in the tank 2 can then be appropriately discharged from the discharge pipe 22 by operating the valve V and reused as needed.

[0043] Furthermore, the suction groove 19 may be arranged at an acute angle with respect to the flow direction of the working fluid flowing through the orifice portion 13, similar to Embodiment 1, as shown in the ejector 1 of Embodiment 3 in Figure 3. According to this embodiment, a large contact area between the gas and the working fluid can be secured, and in addition to the effects of Embodiment 2, the dissolution efficiency of the gas in the working fluid is increased. [Explanation of Symbols]

[0044] 1... Ejector, 10... Suction tube, 11... Inlet, 12... Connecting section, 13... Orifice section, 14... Connecting section, 15... Flow straightening section, 16... Connecting section, 17... Discharge section, 18... Storage section, 19... Suction groove 2...tank, 21...inlet pipe, 22...discharge pipe, V...valve

Claims

1. The orifice through which the working fluid flows, A reservoir is formed around this orifice, into which gas is drawn in, A suction groove with a groove width of 100 μm or less is formed around the orifice portion and supplies the gas from the storage portion to the orifice portion, An ejector characterized by having the following features.

2. An ejector enclosed in a tank into which a gas is drawn in, The orifice through which the working fluid flows, A suction groove with a groove width of 100 μm or less is formed around this orifice portion and supplies the gas in the tank to the orifice portion, An ejector characterized by having the following features.

3. The ejector according to claim 1 or 2, characterized in that the suction groove is formed at an acute angle with respect to the flow direction of the working fluid in the orifice portion.

4. The ejector according to claim 1 or 2, characterized in that the suction grooves are formed to be arranged in a plurality in the direction of the flow of the working fluid in the orifice portion.

5. The ejector according to claim 1 or 2, characterized in that a plurality of suction grooves are formed radially from the orifice portion.

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