JP6178557B2 - Flow control valve - Google Patents

Description

  The present invention relates to a flow control valve used in a refrigerant circulation circuit of an air conditioner such as an air conditioner or a refrigerator.

  Conventionally, the flow control valve has a drive system such as a direct acting type such as an electromagnetic valve, or a gear type such as an electric valve. However, in any type of flow control valve, a needle valve as a valve body is a valve seat. By opening and closing the valve port (orifice) provided in the valve seat, the amount of clearance (valve opening) between the diameter of the needle valve tip and the valve port is adjusted. By doing so, it is configured to control the flow rate.

  As described above, various needle valves and valve seat shapes are employed in the flow rate control valve including the needle valve having the wedge-shaped tip of the valve body and the valve seat constituting the valve port.

  FIG. 4 is a longitudinal sectional view showing an example of such a conventional flow control valve.

  As shown in FIG. 4, the flow control valve 10 is an electric valve and includes a valve body 12, and a valve chamber 14 is formed in the valve body 12. A first piping member 16 and a second piping member 18 are attached so as to communicate with the valve chamber 14.

  In addition, a valve seat 20 is fixed to the valve main body 12 at the upper portion of the first piping member 16, and a valve port 22 is provided in the valve seat 20.

  Further, the female screw member 24 includes a guide member 40, and a fitting portion 24 b that fits to the valve seat 20 is formed at the lower end of the guide member 40, and the fitting portion 24 b of the guide member 40 is provided with the fitting portion 24 b. The female screw member 24 is fixed to the valve seat 20 by being fitted to the valve seat 20. Thereby, the female screw member 24 is fixed in the valve body 12.

  Further, a partition wall 26 is formed above the fitting portion 24 b of the guide member 40 so as to be spaced apart from each other by a certain distance, and the end portion 30 of the partition wall 26 is formed on the inner wall of the valve body 12. The guide member 40 is fixed in the valve main body 12 by fitting.

  Further, the guide member 40 is fixed to the valve body 12 by fitting the fixing bracket 32 to the upper end portion of the valve body 12.

  On the other hand, a main flow path 34 is formed between the fitting portion 24 b of the guide member 40 and the partition wall 26, and an insertion hole 38 through which the needle valve 36 is inserted is formed in the partition wall 26.

  In addition, a substantially cylindrical guide portion 40 a is extended above the partition wall 26, and a female screw 40 b is formed on the inner periphery of the guide portion 40 a of the guide member 40. A male screw 54a of a male screw portion 54 formed at the lower end of the rotor shaft 52 is screwed so as to mesh with the female screw 40b.

  The needle valve 36 is inserted into the needle valve insertion hole 56 formed in the rotor shaft 52, and the needle valve 36 is prevented from falling off by the enlarged diameter portion 36 a formed at the proximal end portion of the needle valve 36. It has become.

  A substantially cylindrical rotor magnet 58 made of a permanent magnet is fitted on the outer periphery of the upper end of the rotor shaft 52 by a fitting portion 58a. A valve opening stopper 60 projects from the lower end of the rotor magnet 58 in the inner circumferential direction, and a valve opening stopper 62 projecting in the outer circumferential direction from the upper end of the guide portion 40a of the guide member 40 is connected to the rotor magnet 58. The valve opening stopper 60 is configured to function as a stopper by abutting when the valve is fully opened.

  Similarly, the valve closing stopper 66 formed at the upper end of the guide portion 40a of the guide member 40 abuts on the valve closing stopper 64 projecting in the outer peripheral direction on the upper end of the rotor shaft 52, thereby contacting the stopper. It is configured to function.

  A spring receiving metal fitting 68 is fitted to the upper end of the rotor shaft 52 at the upper portion of the rotor shaft 52, and above the enlarged diameter portion 36a formed at the proximal end portion of the needle valve 36. 70 is attached. A coil spring 72 in a compressed state is interposed between the spring support fitting 68 and the spring support 70 and is configured to urge the needle valve 36 so as to protrude in the direction of the valve seat 20.

  Furthermore, a bottomed cylindrical case 74 is fixed to the upper portion of the valve body 12 by welding or the like, and inside this case 74 is housed a drive unit 76 composed of these rotor magnets 58, etc. A rotor chamber 28 is formed inside the case 74.

  Further, as shown in FIG. 4, a coil 78 is attached to the outer periphery of the case 74.

  When the flow control valve 10 configured as described above is in a valve open state, the rotor magnet 58 is rotated by generating a feed pulse by the coil 78, and the rotor shaft 52 and the needle valve 36 are rotated together with the rotor magnet 58. Rotating integrally, the male screw 54a of the male screw portion 54 of the rotor shaft 52 and the female screw 40b of the guide portion 40a of the guide member 40 are engaged and guided, and the needle valve 36 moves upward. Thereby, the lower end of the needle valve 36 is separated from the valve port 22 of the valve seat 20 so as to be in the valve open state.

  At this time, as the rotor magnet 58 rotates, the valve opening stopper 60 of the rotor magnet 58 comes into contact with the valve opening stopper 62 projecting outward from the upper end of the guide portion 40a of the guide member 40. As a result, the upper position is regulated.

  From this state, by generating a reverse feed pulse by the coil 78, the rotor magnet 58 rotates in the reverse direction, and together with the rotor magnet 58, the rotor shaft 52 and the needle valve 36 rotate integrally, The male screw 54a of the male screw portion 54 of the rotor shaft 52 and the female screw 40b of the guide portion 40a of the guide member 40 are engaged and guided, and the needle valve 36 moves downward. Thereby, the lower end of the needle valve 36 is in contact with the valve port 22 of the valve seat 20 so that the valve is closed as shown in FIG.

JP-A-6-174129

By the way, in such a flow control valve 10, the intrinsic | native flow characteristic showing the relationship between a valve opening degree and a flow volume is used as the basic characteristic. As such a characteristic flow rate characteristic, it has been conventionally defined in the JIS standard, and as shown in the graph of FIG.
Three types of intrinsic flow characteristics are used: (1) linear characteristics, (2) equal percent characteristics, and (3) quick open characteristics.

  Among these, the linear characteristic (1) is such that the flow rate (%) (Cv value) is proportional to the valve opening, as disclosed in, for example, Patent Document 1 (Japanese Patent Laid-Open No. 6-174129). It is a characteristic flow rate characteristic that changes with time. A flow control valve having such a linear characteristic is used, for example, when the differential pressure of the flow control valve is constant, taking advantage of the characteristic.

  The quick open characteristic (3) is an intrinsic flow characteristic in which the flow rate (%) (Cv value) increases rapidly when the valve starts to open. Such a flow control valve having a quick open characteristic is used, for example, as an on / off flow control valve such as a shutoff valve or an open valve.

  By the way, in recent years, in order to improve the energy saving performance of refrigerators and air conditioners, controllability of the rotational speed of a compressor and the like and improvement of the heat exchange rate of the heat exchanger have become issues. Further, in order to improve the efficiency of the refrigeration cycle, improvement in energy saving performance such as a flow control valve is also required.

Therefore, it is considered that energy saving can be ensured by improving the flow rate control over the conventional flow rate control valve . For this reason, in order to improve the controllability of the flow rate, development of a flow rate control valve capable of controlling a minute flow rate is required.

  However, in the flow control valve 10, the diameter of the needle valve 36, the diameter of the valve port 22, the backlash of the screw feed mechanism including the male screw 54 a of the rotor shaft 52 and the female screw 40 b of the guide member 40, etc. Variations in the flow rate occur due to the influence of the rattling of the stopper positions of the valve opening stopper 62 of 40 and the valve opening stopper 60 of the rotor magnet 58 (hereinafter simply referred to as “variation of valve dimensions and valve opening points”).

  As shown in FIG. 6, in the flow rate control valve having the linear characteristic (1), such a flow rate variation is 100% valve lift (fully opened) (hereinafter simply referred to as “valve lift 100%”). The flow rate variation b2 in FIG. 5 is the same as the flow rate variation b1 of the valve lift 50%, for example, and the flow rate variation is large from the minute flow rate range to the fully open flow rate range.

  Therefore, the flow rate control valve having such a linear characteristic (1) has a large flow rate variation and is used to control the flow rate accurately when used in a control range of a minute flow rate in order to improve the controllability of the flow rate. Unable to do so.

  As a result, it is impossible to provide a flow rate control valve that cannot perform fine flow rate control and that can control minute flow rates.

  On the other hand, the flow rate control valve having the equal percentage characteristic (2) has a characteristic that keeps the flow rate change rate constant as the control valve when energy saving is improved from the control aspect. As shown in FIG. 5, the variation in flow rate in the control region of minute flow rate is small and preferable.

Note that the equal percent characteristic in (2) refers to a characteristic flow characteristic in which an equal increment in relative travel (valve opening) causes an equal ratio increment in a relative capacity coefficient (Cv value = flow rate). It is shown by the following formula.

Here, Ф is a relative capacity coefficient (Cv value = flow rate), Ф ₀ is a relative capacity coefficient (Cv value = flow rate) when h = 0, h is a relative travel (valve opening), and n is This is the slope of the characteristic equal percent characteristic when plotting log _e against h.

  However, in the flow rate control valve having the equal percentage characteristic of (2), as shown in the graph showing the relationship between the valve opening degree and the flow rate in FIG. As the flow rate control valve has a large flow rate variation due to the influence of the open point variation or the like, it is desired to suppress the flow rate variation as much as possible.

  By the way, the most noticeable variation in the flow rate is the state (position) of the valve lift 100% where the flow rate change amount with respect to the change in the valve opening is the largest.

  That is, since the flow rate change amount is large in the vicinity of the valve lift of 100%, the variation in the flow rate due to the variation in the valve dimensions and the valve opening points increases.

  If there is a large variation in the flow rate in a state where the valve lift is 100%, the flow rate is excessive and the flow rate is insufficient (the valve performance is inappropriate).

  In addition, when considering variations in flow rate, it is necessary to increase the valve diameter in order to ensure the flow rate in the fully open state. However, increasing the valve diameter requires high thrust for valve operation. End up.

That is, the state shown by the solid lines in FIGS. 7 and 8 shows a state where there is no variation in valve dimensions and valve opening points (flow rate center). 8 is a partially enlarged cross-sectional view of a portion A in FIG. 4 for explaining the state of the valve lift 100% (fully opened state) in FIG.

  Moreover, the state shown with the dashed-dotted line of FIG. 7, FIG. 8 has shown the state (full open flow upper limit) with the largest fully open flow rate by valve dimension and the variation of a valve open point in 100% of valve lifts. That is, in the valve lift of 100%, the needle valve 36 is located at the uppermost position and is farthest from the valve port 22.

Further, the state shown by the two-dot chain line in FIGS. 7 and 8 shows a state in which the fully open flow rate is the smallest (the fully open flow rate lower limit) due to variations in valve dimensions and valve open points when the valve lift is 100%. That is, in the valve lift of 100%, the needle valve 36 is located in the lowermost position, and shows a state in which is closest from the valve port 22.

  Thus, as shown in FIG. 7, for example, in the state where the valve lift is 50%, the variation in the flow rate of the valve lift 100% in the state of the valve lift 100% rather than the variation B1 in the flow rate of the valve lift 50%. B2 becomes large.

  7 and 8, the valve lift of 100% means that the flow control valve 10 is in a fully opened state (the upper limit position of the operating range of the needle valve 36). That is, in reality, in the mechanical fully open state in which the valve opening stopper 62 of the guide member 40 and the valve opening stopper 60 of the rotor magnet 58 are in contact with each other, the valve opening degree on the right side of the graph of FIG. Located at a large point.

By the way, as shown by hatching in FIG. 8, the valve port area S1 of the valve port 22 and the shortest distance M between the outer periphery of the control part 36c of the needle valve 36 and the valve port 22 in the state of 100% valve lift. The relationship with the valve opening area S2 is valve port area S1> valve opening area S2.

Although the hatching in FIG. 8 schematically shows, as shown in FIG. 9, the valve opening area S2 formed by the outer periphery of the control part 36c of the needle valve 36 and the shortest distance M between the valve port 22 is the upper surface. It is an annular shape in a cross-sectional view as seen from above.

  In this state, the variation in the flow rate depends on the valve opening area S2, and therefore the variation in the flow rate is increased due to the influence of the variation in the valve dimensions and the valve opening points.

The point where the valve port area S1 of the valve port 22 is equal to the valve opening area S2 of the shortest distance M between the outer periphery of the control unit 36c of the needle valve 36 and the valve port 22 is hereinafter referred to as "flow rate saturation point". ).

  In view of such a current situation, the present invention has a small flow rate variation due to variations in valve dimensions and valve opening points, can control a minute flow rate, and can improve the controllability of the flow rate. It aims at providing the flow control valve which can aim at improvement in energy-saving property.

  In addition, the present invention does not cause excessive flow rate or insufficient flow rate (unsuitable valve performance), and it is not necessary to enlarge the valve diameter in order to secure the flow rate in the fully opened state, which is high for valve operation. An object is to provide a compact flow control valve that does not require thrust.

The present invention has been invented in order to achieve the problems and objects in the prior art as described above, and the flow control valve of the present invention comprises:
A flow control valve having a specific flow rate characteristic of equal percentage characteristics, and configured to control the flow rate by opening and closing a valve port provided in the valve seat by separating and contacting the valve body with respect to the valve seat. There,
At a position where the valve lift is 100% or less, the relationship between the valve port area S1 of the valve port and the valve opening area S2 formed by the outer periphery of the control part of the valve body and the shortest distance M of the valve port is:
The valve port area S1 is set to satisfy the valve opening area S2.

  With this configuration, when the valve lift is 100%, the relationship between the valve port area S1 of the valve port and the valve opening area S2 formed by the outer periphery of the valve body and the shortest distance M of the valve port is: Since it is valve opening area S2, a valve body will be located more than a flow rate saturation point with respect to a valve seat (valve port).

  Therefore, in this state, the variation in the flow rate depends on the valve port area S1. That is, the variation in the flow rate when the valve lift is 100% in the fully opened state is affected only by the diameter of the valve port, and the variation in the flow rate can be reduced.

  As a result, there is little variation in flow rate due to variations in valve dimensions and valve opening points, control of minute flow rates is possible, flow rate controllability can be improved, and energy saving performance of refrigerators and air conditioners can be improved. A flow control valve that can be provided can be provided.

In addition, there is no excessive flow rate or insufficient flow rate (inadequate valve capacity), and it is not necessary to enlarge the valve diameter to secure the flow rate in the fully open state, and high thrust is not required for valve operation. A compact flow control valve can be provided.
Further, the flow control valve of the present invention is characterized in that a conical tip portion is provided at the tip of the needle valve of the flow control valve.

The flow control valve according to the present invention is a valve formed by the valve port area S1 of the valve port and the shortest distance M between the outer periphery of the valve body and the valve port at the position of the valve lift of 30% to 100%. The relationship with the opening area S2 is
The valve port area S1 is set to satisfy the valve opening area S2.

  In such a range, if the valve port area S1 ≦ the valve opening area S2, the variation in the flow rate when the valve lift is 100% in the fully opened state is affected only by the diameter of the valve port, and the variation in the flow rate. Can be reduced.

  As a result, the variation in flow rate due to variations in valve dimensions and valve opening points is small, the minute flow rate can be controlled, the flow rate controllability can be improved, and the energy saving performance of the refrigerator and air conditioner can be improved. A flow control valve that can be provided can be provided.

The flow control valve according to the present invention is a valve formed by the valve port area S1 of the valve port and the shortest distance M between the outer periphery of the valve body and the valve port at the position of the valve lift of 50% to 90%. The relationship with the opening area S2 is
The valve port area S1 is set to satisfy the valve opening area S2.

  In such a range, if the valve port area S1 ≦ the valve opening area S2, the variation in the flow rate when the valve lift is 100% in the fully opened state is affected only by the diameter of the valve port, and the variation in the flow rate. Can be reduced.

As a result, the variation in flow rate due to variations in valve dimensions and valve opening points is small, the minute flow rate can be controlled, the flow rate controllability can be improved, and the energy saving performance of the refrigerator and air conditioner can be improved. A flow control valve that can be provided can be provided.
The flow control valve of the present invention is
In the flow control valve, at the position of 50% to 90% of the valve lift, the relationship between the valve port area S1 of the valve port and the valve opening area S2 formed by the outer periphery of the valve body and the shortest distance M of the valve port is:
While setting so that valve port area S1 ≦ valve opening area S2,
The length L of the control portion at the tip of the needle valve of the flow rate control valve is in the range of 40% to 70% with respect to the length L of the control portion in the case of all valve lifts where the valve lift is 100%. It is characterized by setting as follows.

Further, the flow control valve of the present invention is characterized in that the valve lift 100% is in a fully opened state when the flow control valve is used.

With this configuration, when the flow rate control valve is in the fully open state, the flow rate variation at the fully opened valve lift 100% is affected only by the diameter of the valve port, and the flow rate variation. Can be reduced.

  Thereby, in the fully open state in use of the flow rate control valve, the flow rate variation due to variations in valve dimensions and valve open points is small, a minute flow rate can be controlled, and the flow rate controllability can be improved. It is possible to provide a flow control valve capable of improving the energy saving performance of the air conditioner.

  The flow control valve of the present invention is characterized in that the valve lift 100% is in a mechanical full open state in which the valve open stopper is in contact.

  With this configuration, in the mechanical fully open state where the valve opening stopper is in contact, the flow rate variation at 100% of the fully opened valve lift is affected only by the diameter of the valve port. Thus, the flow rate variation can be reduced.

  As a result, in the mechanical full open state where the valve opening stopper is in contact, the flow rate variation due to variations in valve dimensions and valve open points is small, minute flow rate control is possible, and flow rate controllability is improved. Therefore, it is possible to provide a flow control valve capable of improving the energy saving performance of the refrigerator and the air conditioner.

  According to the present invention, at a position where the valve lift is 100% or less, the relationship between the valve port area S1 of the valve port and the valve opening area S2 formed by the outer periphery of the valve body and the shortest distance M of the valve port is the valve port area S1. Since the valve opening area S <b> 2, the valve body is positioned at a flow rate saturation point or higher with respect to the valve seat (valve port).

  Therefore, in this state, the variation in the flow rate depends on the valve port area S1. That is, the variation in the flow rate when the valve lift is 100% in the fully opened state is affected only by the diameter of the valve port, and the variation in the flow rate can be reduced.

  As a result, there is little variation in flow rate due to variations in valve dimensions and valve opening points, control of minute flow rates is possible, flow rate controllability can be improved, and energy saving performance of refrigerators and air conditioners can be improved. A flow control valve that can be provided can be provided.

  In addition, there is no excessive flow rate or insufficient flow rate (inadequate valve capacity), and it is not necessary to enlarge the valve diameter to secure the flow rate in the fully open state, and high thrust is not required for valve operation. A compact flow control valve can be provided.

FIG. 1 is a graph showing the relationship between the valve opening and the flow rate. It is a partial expanded sectional view explaining the state of valve lift 100% (fully opened state). FIG. 3 is a partially enlarged schematic view showing the shape of the needle valve 36. FIG. 4 is a longitudinal sectional view of a conventional flow control valve. FIG. 5 is a graph showing the relationship between the valve opening degree and the flow rate indicating the characteristic flow characteristics of the types. FIG. 6 is a graph showing the relationship between the valve opening degree and flow rate of a flow control valve having linear characteristics. FIG. 7 is a graph showing the relationship between the valve opening degree and the flow rate of the flow rate control valve having equal percent characteristics. 8 is a partially enlarged cross-sectional view of a portion A in FIG. 1 for explaining the state of the valve lift 100% (fully opened state) in FIG. FIG. 9 is a cross-sectional view of the valve opening area S2 formed by the shortest distance M between the outer periphery of the control unit 36c of the needle valve 36 and the valve port 22 as viewed from above.

  Hereinafter, embodiments (examples) of the present invention will be described in more detail with reference to the drawings.

  FIG. 1 is a graph showing the relationship between the valve opening and the flow rate, and FIG. 2 is a partially enlarged cross-sectional view for explaining the state of the valve lift 100% (fully opened state).

  The flow control valve 10 of this embodiment has basically the same configuration as that of the conventional flow control valve 10 shown in FIG. 4, and the same components are denoted by the same reference numerals and the details thereof are described. The detailed explanation is omitted.

  The first piping member 16 may be an inlet joint and the second piping member 18 may be an outlet joint. Conversely, the first piping member 16 may be an outlet joint and the second piping member 18 may be It can also be an inlet joint.

  The flow control valve 10 of this embodiment is a flow control valve having an inherent flow characteristic of equal percent characteristics. That is, the flow control valve 10 having the equal percentage characteristic has a characteristic that keeps the flow rate change rate constant as a control valve when considering energy saving improvement from the control aspect, as shown in FIG. The variation in flow rate in the minute flow rate control range is small.

  In the flow control valve 10 of this embodiment, the state indicated by the solid line in FIG. 1 indicates a state where the valve dimensions and the valve opening points are not varied (flow rate center).

In the flow rate control valve 10 of this embodiment, in the state of the flow rate center, as shown by the solid line in FIG. 1, the position of the valve lift of 100% or less, in this embodiment, the position of the valve lift 90%. In
The relationship between the valve port area S1 of the valve port 22 and the valve opening area S2 formed by the shortest distance M between the outer periphery of the control unit 36c of the needle valve 36 and the valve port 22 is as follows.
The valve port area S1 is set to satisfy the valve opening area S2.

  In the state where the valve lift is 90%, the state indicated by the alternate long and short dash line in FIG. 1 indicates the state where the full open flow rate is the largest (full open flow upper limit) due to variations in valve dimensions and valve open points. In this state, the valve port area S1 <the valve opening area S2.

  On the other hand, in the state where the valve lift is 90%, the state indicated by a two-dot chain line in FIG. 1 indicates a state where the full open flow rate is the smallest (full open flow lower limit) due to variations in valve dimensions and valve open points. In this state, the valve port area S1> the valve opening area S2.

  In the state where the valve lift is 100%, as shown in FIGS. 1 and 2, the valve port area S1 ≦ the valve opening area S2 even in the state where the full open flow rate indicated by the two-dot chain line is the smallest (full open flow lower limit). It is in the state of.

Therefore, in the state where the valve lift is 100%, the valve port area S1 of the valve port 22 and the needle valve 36 which is the valve body of the valve port 22 are in any state of the flow rate center state, the fully open flow rate upper limit state and the fully open flow rate lower limit state. The relationship between the outer periphery of the control unit 36c and the valve opening area S2 formed by the shortest distance M between the valve port 22 is valve port area S1 ≦ valve opening area S2.

  Thereby, the needle valve 36 which is a valve body is located above the flow rate saturation point with respect to the valve seat 20 (valve port 22).

  Therefore, in this state, the variation in the flow rate depends on the valve port area S1. That is, the variation in flow rate when the valve lift is 100% in the fully open state is affected only by the diameter of the valve port 22, and as shown in the graph of FIG. 1, the variation in flow rate when the valve lift is 100%. B3 can be reduced.

  As a result, there is little variation in flow rate due to variations in valve dimensions and valve opening points, control of minute flow rates is possible, flow rate controllability can be improved, and energy saving performance of refrigerators and air conditioners can be improved. A possible flow control valve 10 can be provided.

  In addition, there is no excessive flow rate or insufficient flow rate (inadequate valve capacity), and it is not necessary to enlarge the valve diameter to secure the flow rate in the fully open state, and high thrust is not required for valve operation. A compact flow control valve can be provided.

In this case, the position of the valve lift of 100% or less is set at the position of the valve lift of 90% in the above embodiment, but is not limited in any way, but preferably the valve lift is 30% to 100% or less. It is desirable to set the valve lift at a position of 50% to 90% or less.
That is, if it is below this range, the control resolution of the flow rate control valve 10 is small and unsuitable for practical use, and if it is above this range, the influence of the variation in the flow rate becomes large.

  In such a range, if the valve port area S1 ≦ the valve opening area S2, the variation in the flow rate when the valve lift is 100% in the fully opened state is affected only by the diameter of the valve port 22, and the flow rate Variations can be reduced.

  As a result, the variation in flow rate due to variations in valve dimensions and valve opening points is small, the minute flow rate can be controlled, the flow rate controllability can be improved, and the energy saving performance of the refrigerator and air conditioner can be improved. A possible flow control valve 10 can be provided.

Further, in this case, the valve lift of 100% means that the flow control valve 10 is in a fully opened state (the upper limit position of the operating range of the needle valve 36).

  That is, in actuality, the mechanical opening state where the valve opening stopper 62 of the guide member 40 and the valve opening stopper 60 of the rotor magnet 58 are in contact with each other has a valve opening degree on the right side of the graph of FIG. Located at a large point.

With this configuration, when the flow control valve is used in a fully open state, the variation in the flow rate when the valve lift is 100% in the fully open state is affected only by the diameter of the valve port 22, and the flow rate Variations can be reduced.

  Thereby, in the fully open state in use of the flow rate control valve, the flow rate variation due to variations in valve dimensions and valve open points is small, a minute flow rate can be controlled, and the flow rate controllability can be improved. It is possible to provide the flow control valve 10 that can improve the energy saving performance of the air conditioner.

  In the flow control valve of the present invention, the valve lift 100% may be in a mechanical full open state in which the valve open stopper is in contact.

  With this configuration, in the mechanical fully open state where the valve opening stopper is in contact, the flow rate variation at the fully opened valve lift 100% is affected only by the diameter of the valve port 22. As a result, the variation in flow rate can be reduced.

  As a result, in the mechanical full open state where the valve opening stopper is in contact, the flow rate variation due to variations in valve dimensions and valve open points is small, minute flow rate control is possible, and flow rate controllability is improved. Therefore, it is possible to provide a flow control valve capable of improving the energy saving performance of the refrigerator and the air conditioner.

It should be noted that at a position where the valve lift is 100% or less, the relationship between the valve port area S1 of the valve port 22 and the valve opening area S2 formed by the shortest distance M between the outer periphery of the control unit 36c of the needle valve 36 and the valve port 22 is A method for setting the port area S1 ≦ the valve opening area S2 is not particularly limited, such as changing the shape of the needle valve 36.

  For example, when the valve lift is 50 to 90% or less and the valve port area S1 ≦ the valve opening area S2, the curved shape at the tip of the needle valve 36 of the flow control valve 10 is shown as the hatched portion in FIG. The length L of the control unit 36c is set to 40% to 70% with respect to the length L of the control unit 36c in the case of all valve lifts (valve port area S1 ≦ valve opening area S2) where the valve lift is 100%. What is necessary is just to set so that it may become the range of%.

That is, when the valve lift is 50 to 90% or less and the valve port area S1 ≦ the valve opening area S2, the length L of the controller 36c is the height of the cone of the opening area M (the opening area M of FIG. The height of the hatched portion) is shorter than the length L of the control unit 36c in the case of all valve lifts (valve port area S1 ≦ valve opening area S2) where the valve lift is 100%. Therefore, it is in the range of 40% to 70% with respect to the length L of the control unit 36c in the case of all valve lifts where the valve lift is 100%.

  That is, the part of the control part 36c of the needle valve 36 of the flow control valve 10 is the part that actually affects the flow characteristic of the flow control valve 10, and the part that makes the flow control valve 10 equal percent characteristic by this curved shape. Because.

  As shown in FIG. 3, the tip portion 36 d of the needle valve 36 of the flow control valve 10 is a portion that does not affect the flow characteristics of the flow control valve 10. That is, since the diameter is smaller than the opening area of the valve port 22, it is a portion that does not affect the flow characteristics of the flow control valve 10.

The tip portion 36d of the needle valve 36 prevents the fluid from directly contacting the control unit 36c when the first piping member 16 is an inlet joint and the second piping member 18 is an outlet joint. It also has a function.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to this. For example, in the above embodiment, the valve body is applied to a flow control valve in the shape of a needle valve. The shape of the valve body can be changed as appropriate.

  In the above embodiment, the flow control valve applied to the motor-operated valve has been described. However, the flow control valve can be applied to a flow control valve driven by another actuator such as an electromagnetic valve. Various changes are possible.

  The present invention can be applied to, for example, a flow rate control valve that can be used for a refrigerant circulation circuit of an air conditioner such as an air conditioner or a refrigerator and that can control a minute flow rate.

DESCRIPTION OF SYMBOLS 10 Flow control valve 12 Valve main body 14 Valve chamber 16 1st piping member 18 2nd piping member 20 Valve seat 22 Valve port 24 Female thread member 24b Fitting part 26 Partition 28 Rotor chamber 30 End part 32 Fixing metal fitting 34 Main flow path 36 Needle valve
36a Diameter expansion part
36c Control part 36d Tip part 38 Insertion hole 40 Guide member 40a Guide part 40b Female screw 52 Rotor shaft 54 Male screw part 54a Male screw 56 Needle valve insertion hole 58 Rotor magnet 58a Fitting part 60 Valve opening stopper 62 Valve opening stopper 64 Valve Closing stopper 66 Valve closing stopper 68 Bracket 72 Coil spring 74 Case 76 Drive section 78 Coil B1 Flow rate variation b1 Flow rate variation b2 Flow rate variation B2 Flow rate variation B3 Flow rate variation M Shortest distance S1 Valve port area S2 Valve opening area

Claims (7)

A flow control valve having a specific flow rate characteristic of equal percentage characteristics, and configured to control the flow rate by opening and closing a valve port provided in the valve seat by separating and contacting the valve body with respect to the valve seat. There,
At a position where the valve lift is 100% or less, the relationship between the valve port area S1 of the valve port and the valve opening area S2 formed by the outer periphery of the control part of the valve body and the shortest distance M of the valve port is
A flow rate control valve set so that the valve port area S1 ≦ the valve opening area S2.   The flow control valve according to claim 1, further comprising a conical tip portion at a tip of the needle valve of the flow control valve. In the flow control valve, at the position of the valve lift of 30% to 100%, the relationship between the valve port area S1 of the valve port and the valve opening area S2 formed by the outer periphery of the valve body and the shortest distance M of the valve port is:
3. The flow rate control valve according to claim 1, wherein the flow rate control valve is set so that the valve port area S1 ≦ the valve opening area S2. In the flow control valve, at the position of 50% to 90% of the valve lift, the relationship between the valve port area S1 of the valve port and the valve opening area S2 formed by the outer periphery of the valve body and the shortest distance M of the valve port is:
4. The flow rate control valve according to claim 3, wherein the valve port area S1 is set to satisfy the valve opening area S2. In the flow control valve, at the position of 50% to 90% of the valve lift, the relationship between the valve port area S1 of the valve port and the valve opening area S2 formed by the outer periphery of the valve body and the shortest distance M of the valve port is:
While setting so that valve port area S1 ≦ valve opening area S2,
The length L of the control portion at the tip of the needle valve of the flow rate control valve is in the range of 40% to 70% with respect to the length L of the control portion in the case of all valve lifts where the valve lift is 100%. The flow control valve according to claim 3, wherein the flow control valve is set as follows.   The flow rate control valve according to any one of claims 1 to 5, wherein the valve lift 100% is in a fully opened state when the flow rate control valve is used.   The flow rate control valve according to any one of claims 1 to 5, wherein the valve lift 100% is a mechanically fully opened state in which a valve opening stopper is in contact.

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