JP7050347B2 - Flow control valve - Google Patents

Description

The present invention relates to a flow rate adjusting valve including a valve body provided with a valve chamber and a valve port (orifice) and a valve body that changes the flow rate of the fluid flowing through the valve port according to the lift amount. The present invention relates to a flow rate adjusting valve suitable for adjusting a refrigerant flow rate in a heat pump type heating / cooling system or the like.

The relationship between the valve opening (lift amount) and the flow rate in the flow rate adjusting valve, that is, the linear characteristic and the equal percent characteristic are well known as the flow rate characteristics. The linear characteristic refers to a characteristic in which the rate of change in flow rate with respect to a change in valve opening is constant, and the equal percentage characteristic refers to a characteristic in which the rate of change in valve opening is proportional to the flow rate.

FIG. 5 shows the main part of an example of a flow control valve in which equal percent characteristics are obtained. The flow rate adjusting valve 1'in the illustrated example is used for adjusting the flow rate of the refrigerant in a heat pump type heating / cooling system or the like, and has a valve chamber 6, a valve seat 8 made of an inverted conical base surface, and a valve port made of a cylindrical surface. A valve body 5 provided with 15 and a valve body 20 that changes the flow rate of the fluid flowing through the valve port 15 according to the amount of lift from the valve seat 8 are provided, and the valve body 20 is described in, for example, Patent Document 1. As shown in the above, a screw feed type elevating drive mechanism composed of a valve shaft provided with a male thread, a guide stem provided with a female thread, a stepping motor, and the like is used to raise and lower the valve seat 8 so as to be in contact with and separated from the valve seat 8.

The valve body 20 has a contact surface portion 22 that contacts the valve seat 8 and an elliptical curved surface portion 23 that is connected to the lower side of the contact surface portion 22 and is connected to the lower side to obtain an equal percent characteristic as a flow rate characteristic. The curved surface portion 23 has a shape similar to the lower half of the egg, and the outer peripheral surface thereof is gradually bent from the upper end 23a to the lower end 23b (the curvature is large).

In the flow control valve 1'in which the equal percent characteristic is obtained, as shown by the thick arrow in FIG. 5, when the refrigerant flow direction is from the valve chamber 6 to the valve port 15, the refrigerant is the curved surface portion 23. However, there is a problem that sudden pressure fluctuations and refrigerant separation phenomena are likely to occur when passing through the valve port 15, and as a result, vortices and cavitation are likely to occur and grow, and relatively loud noise is generated.

It should be noted that providing the elliptical curved surface portion 23 on the valve body 20 in order to obtain the equal percent characteristic as described above has problems in terms of processing cost, cost effectiveness, etc., and is therefore shown in FIG. , A flow control valve 1'' has been developed so that characteristics close to the equal percent characteristics can be obtained. In the flow rate adjusting valve 1'' of the illustrated example, the valve chamber forming member 6A is fixed, and the valve port 17 is composed of a first valve port 17A formed of a short cylindrical surface and a second valve port 17B formed of a conical base surface. The flow rate of the fluid flowing through the valve port 17 according to the lift amount from the valve seat 8 and the valve body 5 to which the pipe joint 14 to which the conduit is connected is connected to the lower outer periphery of the second valve port portion 17B is provided. It is provided with a valve body 30 to be changed.

The valve body 30 has a seating surface portion 32 seated on the valve seat 8 and a curved surface portion 33 connected to the lower side of the seating surface portion 32 to obtain a characteristic similar to an equal percent characteristic as a flow rate characteristic. The curved surface portion 33 has a plurality of stages (here, 5 stages) in which the control angle (intersection angle between the central axis O of the valve body 30 and the line parallel to the line) is gradually increased as it approaches the tip so as to imitate an elliptical spherical surface. The first control angle θ1 of the uppermost conical tapered surface portion 33A is usually set to 3 ° <θ1 <15 ° (here, 5 °), and the lowermost conical tapered surface portion 33A to 33E is provided. The conical tapered surface portion 33E is a conical surface with a sharp point.

On the other hand, in Patent Document 2, in a flow rate adjusting valve in which a normal linear characteristic can be obtained, the dimensional shape of the valve opening is specified, and as described above, the pressure fluctuation and the refrigerant separation when passing through the valve opening are specified. A device that suppresses noise generated due to a phenomenon or the like is disclosed.

Japanese Unexamined Patent Publication No. 2012-172839 Japanese Patent No. 5696093

However, in the flow rate adjusting valve described in Patent Document 2, since it is necessary to set the valve port length to be considerably long, there is a problem that the pressure loss becomes large and it is difficult to obtain an appropriate flow rate of the refrigerant, and further, the valve. Since the size and shape of the mouth are matched to the valve body for linear characteristics, even if it is applied to the flow control valve having the above-mentioned equal percent characteristics and characteristics similar to it, a sufficient noise reduction effect cannot be obtained. ..

The present invention has been made in view of the above circumstances, and an object of the present invention is to be able to effectively reduce noise generated due to pressure fluctuation and refrigerant separation phenomenon when passing through a valve port, and to reduce pressure loss. The purpose of the present invention is to provide a flow rate adjusting valve that can reduce the amount of noise.

In order to achieve the above object, the flow control valve according to the present invention is basically a valve body provided with a valve chamber and a valve port, a pipe joint connected to the valve port, and a lift amount. A valve body that changes the flow rate of the fluid flowing through the valve port is provided, and the valve port is a first valve port portion of a cylinder having a diameter of D1 and a second valve port of a cylinder having a diameter of D2 in order from the valve chamber side. A portion and a third valve mouth portion of a cylinder of D3 are provided, and D1 <D2 <D3, and the valve body is a valve chamber forming member defining the valve chamber and a member on which the valve opening is formed. The pipe joint is connected to the valve body so that at least the third valve port portion is arranged inside the pipe joint, and the valve port is formed. The member has a groove into which the end portion of the pipe joint on the valve chamber side is inserted, and the third valve opening portion protrudes toward the counter valve chamber side from the outer peripheral portion of the groove, and 1.08 <( It is characterized in that D2 / D1) <1.37 .

In the flow rate adjusting valve according to the present invention, the diameter of the valve opening is sequentially increased in three or more steps from the valve chamber side to the lower end side, so that the refrigerant pressure is gradually recovered when passing through the valve opening, and the pressure fluctuation is suppressed. It is rectified. Further, by setting (D2 / D1) and (D3 / D2) within a specific range, the generation / growth of vortices and cavitation due to pressure fluctuation and refrigerant separation phenomenon can be suppressed. Further, by setting (D2 / D1) <(D3 / D2) <(D4 / D3), the flow becomes smoother. The level can be lowered considerably.

Further, by setting (L2 / D1) and (L4 / D1) in a specific range, the valve opening length L2 is described in Patent Document 2 and the flow rate adjustment having the equal percent characteristic shown in FIG. Since it is shorter than the valve 1', the pressure loss is small and an appropriate refrigerant flow rate can be obtained.

The cross-sectional view of the main part which shows the main part in one Embodiment of the flow rate control valve which concerns on this invention. A list showing actual measurement data of (A) verification valves Nos. 1 to 4 with partially changed specifications and specifications for confirming and proving the operation and effect of the present invention, (B) verification conditions A to A list showing G. (A) A graph showing the measured values of the verification valves Nos. 1 to 4 for each of the verification conditions A to G, with the diameter ratio: D2 / D1 on the horizontal axis and the noise level [dB] on the vertical axis. B) The graph showing the measured values of the verification valves Nos. 1 to 4 for each of the verification conditions A to G, with the diameter ratio: D3 / D2 on the horizontal axis and the noise level [dB] on the vertical axis. (A) A list showing actual measurement data of verification valves Nos. 5 to 8 with partially changed specifications and specifications, (B) Verification condition H, for confirming and proving the operation and effect of the present invention. List showing I, (C) Valve opening length ratio: L4 / D1 is taken on the horizontal axis, sound pressure level [dB] is taken on the vertical axis, and the measured values of the verification valves No. 5 to 8 are the verification conditions. Graph shown for each of H and I. A partial cross-sectional view showing a main part of an example of a flow control valve in which equal percent characteristics are obtained. (A) A partial cross-sectional view when the valve is closed and (B) a partial cross-sectional view when the valve is opened, showing a main part of an example of a flow rate control valve in which characteristics close to the equal percent characteristic can be obtained.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a cross-sectional view of a main part showing a main part in one embodiment of the flow control valve according to the present invention. In addition, in FIG. 1, a common reference numeral is attached to a portion corresponding to each portion of the conventional flow rate adjusting valve 1 ″ shown in FIG. 6 described above.

The flow rate adjusting valve 1 of the illustrated embodiment is the same as the conventional flow rate adjusting valve 1'' shown in FIG. 6 described above, so that characteristics close to the equal percent characteristics can be obtained, and the valve chamber forming member. 6A is fixed, and the flow rate of the fluid flowing through the valve port 10 according to the lift amount from the valve seat 8 and the valve body 5 provided with the valve port 10 (details will be described later), which is a feature of the present invention, is measured. It is provided with a valve body 30 to be changed. The valve body 30 has the same configuration as the conventional flow rate adjusting valve 1'' shown in FIG. 6, and has a seating surface portion 32 seated on the valve seat 8 and an equal percent characteristic as a flow rate characteristic connected to the lower side of the seating surface portion 32. It has a curved surface portion 33 for obtaining a characteristic similar to that of. The curved surface portion 33 has a plurality of stages (here, 5 stages) in which the control angle (intersection angle between the central axis O of the valve body 30 and the line parallel to the line) is gradually increased as it approaches the tip so as to imitate an elliptical spherical surface. The first control angle θ1 of the uppermost conical tapered surface portion 33A is set to 3 ° <θ1 <15 ° (here, 5 °), and the lowermost conical tapered surface portion 33A to 33E is provided. The surface portion 33E is a conical surface with a sharp point.

The valve opening 10 that opens into the valve chamber 6 has a cylindrical first valve opening portion 11 having a diameter of D1 and a cylindrical second valve opening portion 12 having a diameter of D2, in order from the valve chamber 6 side. A cylindrical third valve port portion 13 having a diameter of D3 is provided, and a pipe joint 14 having an inner diameter of D4 to which a conduit is connected is connected to the lower outer periphery of the third valve port portion 13. Here, D1 <D2 <D3 <D4, and the valve port 10 is gradually increased in three stages as the diameter thereof moves away from the valve chamber 6.

Here, in the present embodiment, (diameter ratio: D2 / D1) <(diameter ratio: D3 / D2) <(diameter ratio: D4 / D3) is set, and (D2 / D1) and (D3 / D2). Is set within a specific range, that is, 1.08 <(D2 / D1) <1.37 and 1.05 <(D3 / D2) <1.43, respectively, based on prototype experiments and the like. There is.

Further, a truncated cone-shaped tapered surface portion 16 having a taper angle of θu is formed between the first valve port portion 11 and the second valve port portion 12 (step portion), and the second valve port portion 12 and the third valve port portion 12 and the third. A truncated cone-shaped tapered surface portion 18 having a taper angle of θv is formed between the valve port portion 13 and the step portion.

Further, the valve port length of the first valve port portion 11 (the length in the central axis O direction) is L1, the valve port length of the second valve port portion 12 is L2, and the valve port length of the third valve port portion 13 is L3. The length from the upper end of the second valve opening portion 12 to the lower end of the third valve opening portion 13 is L4, and (valve opening length ratio: L2 / D1) and (valve opening length ratio: L4 / D1) are respectively. Based on a prototype experiment or the like, it is set within a specific range, that is, 1.0 <(L2 / D1) <2.0 and 2.3 <(L4 / D1) <4.0.

In the flow rate adjusting valve according to the present invention having such a configuration, the diameter of the valve port 10 is gradually increased in three stages as the distance from the valve chamber 6 increases, so that the refrigerant pressure gradually recovers when passing through the valve port. , Pressure fluctuation is suppressed and rectification is achieved. Further, by setting (D2 / D1) and (D3 / D2) within a specific range, the generation / growth of vortices and cavitation due to pressure fluctuation and refrigerant separation phenomenon can be surely suppressed. Furthermore, by setting (D2 / D1) <(D3 / D2) <(D4 / D3), the flow becomes smoother. Can be made considerably lower.

Further, by setting (L2 / D1) and (L4 / D1) in a specific range, the flow rate at which L2 (or L1) is described in Patent Document 2 or has the equal percent characteristic shown in FIG. Since it is shorter than the regulating valve 1', the pressure loss is small and an appropriate refrigerant flow rate can be obtained.

[Verification test and results to verify the appropriate range of diameter ratio and valve opening length ratio]
In order to confirm and prove the above-mentioned effects, the present inventors have changed some of the specifications and specifications as shown in the lists of FIGS. 2 (A) and 4 (A). Caliber ratio << (D2 / D1), (D3 / D2) >> verification valves Nos. 1 to 4, and valve opening length ratio << (L4 / D1) >> verification valves Nos. 5 to 8 are prepared. A verification test was conducted under the conditions A to G shown in 2 (B) and the conditions H and I shown in FIG. 4 (B). Diameter ratio << (D2 / D1), (D3 / D2) >> The test results of the verification valves Nos. 1 to 4 are shown in FIGS. 3A and 3B, and the valve opening length ratio << (L4 / D1). >> The test results of the verification valves Nos. 5 to 8 are shown in FIG. 4 (C).

In FIG. 3A, the horizontal axis is the diameter ratio: D2 / D1, the vertical axis is the noise level [dB], and the measured values of the verification valves Nos. 1 to 4 are the verification conditions A to G. In the graphs shown for each, FIG. 3B, the horizontal axis is the diameter ratio: D3 / D2, and the vertical axis is the noise level [dB], and the measured values of the verification valves Nos. 1 to 4 are verified. In the graphs shown for each of the conditions A to G, FIG. 4 (C) shows the valve port length ratio: L4 / D1 on the horizontal axis and the sound pressure level [dB] on the vertical axis, and the verification valve No. 5 It is a graph which showed the measured value of 8 to 8 for each verification condition H, I.

Further, in the graphs of FIGS. 3 (A), 3 (B) and 4 (C), the level 0 (reference) is a flow rate regulating valve 1 having a characteristic similar to the conventional equal percent characteristic shown in FIG. 6 described above. '' (Hereinafter referred to as a conventional product) noise level and sound pressure level are shown.

From the graph of FIG. 3A, the noise level is lower than that of the conventional product when the diameter ratio: (D2 / D1) is 1.05 to 1.45 (nearly the entire range shown in the figure), and in particular, the valve No. Although the noise reduction effect per .3 and valve No. 2 is large, (D2 / D1) is 1.08 (caliber ratio of valve No. 4) to 1.37 (≈ (1.31 + 1.42) / 2, It was confirmed that the noise can be significantly reduced as compared with the conventional product if it is within the range (diameter ratio between valve No. 2 and valve No. 1).

From the graph of FIG. 3B, the noise level is lower than that of the conventional product when the diameter ratio: (D3 / D2) is 1.00 to 1.50 (almost the entire range shown in the figure), and in particular, the valve No. The noise reduction effect per .3 and valve No. 2 is large, but (D3 / D2) is 1.08 to 1.43 (≈ (1.35 + 1.50) / 2, valve No. 3 and valve No. 4). It was confirmed that noise can be significantly reduced compared to the conventional product if it is within the range of the diameter ratio in the middle of the above.

From the graph of FIG. 4C, the sound pressure level is equal to or lower than that of the conventional product when the valve opening length ratio: (L4 / D1) is 2.00 to 4.00 (almost the entire range shown in the figure). In particular, the noise reduction effect per valve No. 6 is large, but (L4 / D1) is 2.30 (larger than the valve opening length ratio of valve No. 5) to 4.00 (valve No. 8). It was confirmed that the noise reduction effect can be obtained as compared with the conventional product (for example, the sound pressure level is 2 dB or more lower than the standard under the condition I) if it is within the range of the valve opening length ratio).

Although not shown, if the valve opening length ratio: (L2 / D1) is in the range of 1.0 to 2.0, the sound pressure level is equal to or lower than that of the conventional product, and the conventional product. It has also been confirmed that a more noise reduction effect can be obtained.

In the above embodiment, the case where the present invention is applied to the flow rate control valve 1 having a characteristic close to the equal percent characteristic has been described, but the present invention is not limited to this, and the present invention is shown in FIG. It can be applied not only to the flow rate adjusting valve 1'having the equal percent characteristic as described above, but also to the flow rate adjusting valve having the linear characteristic described in Patent Documents 1, 2 and the like.

Further, in the above embodiment, the curved surface portion of the valve body is composed of a plurality of conical tapered surface portions in which the control angle is gradually increased toward the tip side, but the present invention is not limited to this, and FIG. The elliptical spherical surface portion as shown, or the lower end portion (elliptical spherical crown portion) of the elliptical spherical surface portion may be cut off, or further, the elliptical spherical surface portion may be combined with one or more conical tapered surface portions. It may be configured.

Further, in the above-described embodiment, the pipe joint 14 having an inner diameter of D4 is connected to the third valve opening portion 13, but the fourth valve having a diameter of D4 is connected to the valve chamber side of the third valve opening portion 13. Needless to say, even if the mouth is formed, the same action and effect as described above can be obtained.

1 Flow control valve 5 Valve body 6 Valve chamber 10 Valve port 11 1st valve port 12 2nd valve port 13 3rd valve port 14 Pipe joint 30 Valve body 33 Curved surface D1 1st valve port diameter D2 No. 2 Diameter of valve port D3 Diameter of third valve port D4 Inner diameter of pipe joint L1 Valve port length of first valve port L2 Valve port length of second valve port L3 Valve port length of third valve port L4 2nd to 3rd valve opening length

Claims (1)

It is provided with a valve body provided with a valve chamber and a valve port, a pipe joint connected to the valve port, and a valve body that changes the flow rate of the fluid flowing through the valve port according to the lift amount.
The valve port is provided with a first valve port portion of a cylinder having a diameter of D1, a second valve port portion of a cylinder of D2, and a third valve port portion of a cylinder of D3, in order from the valve chamber side, and D1. <D2 <D3,
The valve body is configured by fixing a valve chamber forming member that defines the valve chamber and a member on which the valve opening is formed.
The pipe joint is connected to the valve body so that at least the third valve opening portion is arranged inside the pipe joint.
The member on which the valve opening is formed has a groove into which the end portion of the pipe joint on the valve chamber side is inserted.
The third valve opening portion projects toward the valve chamber side from the outer peripheral portion of the groove.
A flow rate adjusting valve characterized in that 1.08 <(D2 / D1) <1.37 .

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