JP2020008105A - Temperature-sensitive control valve - Google Patents

Abstract

To quickly supply a refrigerant in accordance with temperature change of a heat source, in a temperature-sensitive control valve 100 disposed in refrigerant supply piping of a cooling device for cooling the heat source requiring cooling.SOLUTION: A temperature-sensitive control valve includes a thermoelement 20 for advancing and retracting a piston 23 in a direction of axis L according to volume change of a thermal expansion body expanding and contracting according to temperature change. A valve port 13 through which a refrigerant flows, is opened and closed by a valve element 3. The valve element 3 is energized in a valve closing direction of a coil spring 32 (valve closing spring). A structural portion including the valve element 3 is tightly sealed by a diaphragm 43. An operation portion 4 is disposed to transmit mechanical pressing force in the direction of axis L to the valve element 3 through the diaphragm 43. The diaphragm 43 is constituted to energize tensile force of the diaphragm 43 to the valve element 3 in a valve opening direction, in closing the valve by the valve element 3.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a temperature-responsive control valve that supplies a refrigerant to a cooling device or the like that cools a heat source.

  2. Description of the Related Art Conventionally, for example, in the information processing field, a system that generates a large amount of heat, such as a server, is cooled by a circulating refrigerant. For example, Japanese Unexamined Patent Application Publication No. 2009-224406 (Patent Document 1) discloses a waste heat utilization system in which a cooling device is arranged in a rack of a blade server to cool the inside of the rack. JP-A-2017-67164 (Patent Document 2) discloses a thermoelement and a piston assembly suitable for sensing the temperature of a heat source.

JP 2009-224406 A JP 2017-67164 A

  In the technique of Patent Literature 1, cooling is performed using cooling water (refrigerant). However, in a device such as a server, the amount of heat generated varies greatly depending on the operation state. For this reason, when the heat source reaches the set temperature, it is required to immediately open the valve port, immediately flow the amount of refrigerant required for cooling, and quickly cool the heat source.

  The present invention is a temperature-sensitive control valve that is provided in a refrigerant supply pipe of a cooling device that cools a heat source that requires cooling, and when the heat source reaches a set temperature, opens a valve port widely and can supply the refrigerant quickly. The task is to provide

  A temperature-sensitive control valve according to a first aspect of the present invention provides a thermo-element for moving a piston in an axial direction by a volume change of a thermal expansion body which expands and contracts in response to a temperature change, and a valve port for flowing a refrigerant by a valve closing spring to close the valve. A valve device main body that opens and closes with a valve body biased to the valve body, and a structure including the valve body is hermetically sealed with a diaphragm, and the mechanical pressing force in the axial direction is applied through the diaphragm. A valve device main body having an operating portion for transmitting the valve body in the axial direction, the diaphragm having a height of an operating surface of the diaphragm that urges the pressing force when the valve is closed by the valve body. The diaphragm is configured to be located at a position higher than a working surface of the diaphragm in a natural state.

  The temperature-sensitive control valve according to claim 2 is the temperature-sensitive control valve according to claim 1, wherein the valve device main body has a valve housing, and a valve chamber is formed in the valve housing; A first port through which the refrigerant flows into the valve chamber and a second port through which the refrigerant flows out from the valve chamber are formed on a side wall of the valve housing, and the first port is formed between the valve chamber and the second port in the axial direction. A valve port is formed, the operating section is provided on an upper portion of the valve device main body, and a lower portion of the diaphragm communicates with the second port.

  The temperature-sensitive control valve according to claim 3 is the temperature-sensitive control valve according to claim 1, wherein in the temperature-valve lift characteristics, the height of the working surface of the diaphragm is a height in a natural state. Is a liquid expansion region of the thermal expansion body in the temperature sensing portion of the thermoelement.

  According to the temperature-sensitive control valve of the first to third aspects, in the valve closed state at the time of assembling, the height of the operating surface of the diaphragm of the operating portion in the axial direction of the pressing force is an initial single state before assembling, that is, naturally. Since the height of the diaphragm is higher than the height in the state, the tension of the diaphragm is generated downward, so that the valve element is provided so as to urge the valve body in the valve opening direction, and the piston of the thermoelement is the same as the pressing force acting on the operating portion. Since the diaphragm also urges the valve body in the direction, the characteristics of the valve opening degree become steep with respect to the temperature change, and when the valve is opened, the refrigerant can flow quickly through the valve port, and the heat source Following the temperature change, the refrigerant can be quickly supplied to the cooling device or the like, and the heat source can be rapidly cooled.

  According to the temperature-sensitive control valve of the second aspect, when the refrigerant flows into the valve chamber from the first port and is throttled at the valve port, the refrigerant enters a low pressure state and flows out from the second port. Since the lower part of the diaphragm receives the low pressure of the second port from which the refrigerant flows out, the diaphragm is more easily displaced in the valve opening direction, so that the refrigerant can flow more quickly at a large flow rate.

  According to the temperature-sensitive control valve of the third aspect, in the temperature-lift characteristics, the area where the height of the working surface of the pressure force of the assembled diaphragm becomes the height in the natural state is the heat in the temperature-sensitive portion of the thermoelement. When the solid-liquid mixed expansion region of the expander is used, at a higher temperature, the tension of the diaphragm acts in the valve closing direction, the slope of the temperature-lift characteristic becomes gentler, and a rapid increase in the refrigerant flow rate is not expected. In the case of the liquid expansion region, the reversal of the diaphragm tension in the valve closing direction becomes a high temperature, and the temperature-valve lift characteristic can be steeply maintained at a higher temperature than in the case of the solid-liquid mixed expansion region. The refrigerant can flow at a large flow rate.

It is a longitudinal section of a temperature sensitive control valve of an embodiment of the present invention. FIG. 2 is a top view of the temperature-sensitive control valve according to the embodiment of the present invention. It is a longitudinal section of a thermoelement in a temperature-responsive control valve of an embodiment of the present invention. It is a figure showing the temperature-displacement characteristic of the thermo element in the temperature-responsive control valve of the embodiment of the present invention. It is sectional drawing explaining two states of the diaphragm in the temperature-responsive control valve of embodiment of this invention. It is a figure showing the temperature-valve lift characteristic in the temperature-responsive control valve of an embodiment of the present invention.

  Next, an embodiment of a temperature-sensitive control valve of the present invention will be described with reference to the drawings. 1 is a longitudinal sectional view of the temperature-sensitive control valve of the embodiment, FIG. 2 is a top view of the temperature-sensitive control valve, and FIG. 3 is a longitudinal sectional view of a thermo-element in the temperature-sensitive control valve. Note that the concept of “up and down” in the following description corresponds to the up and down directions in FIGS. 1 and 3. In the following description, the temperature-sensitive control valve according to the embodiment will be appropriately referred to as a “control valve”.

  The control valve 100 of the embodiment includes a valve device main body 10 and a thermoelement 20. The valve device main body 10 has a metal valve housing 1, and a cylindrical valve chamber 1 </ b> A is formed in the center of the valve housing 1. One port 11 is formed, and further, a second port 12 through which the refrigerant flows out is formed. In the valve housing 1, a valve port 13 having an axis L as a center is formed between the valve chamber 1 </ b> A and the second port 12, and the second port is coaxial with the valve port 13 from above the valve housing 1. A guide hole 14 penetrating up to 12 is formed. The guide hole 14 has a cylindrical shape with the axis L of the valve port 13 as a central axis. In some cases, the refrigerant may flow in from the second port 12 and flow out of the first port.

  The valve body 3 is disposed in the valve chamber 1A, the second port 12, and the guide hole 14. The valve body 3 includes a cylindrical rod-shaped valve rod 3a, a substantially conical needle part 3b for opening and closing the valve port 13 from the valve chamber 1A side, and a flange part 3c formed on the outer periphery of the needle part 3b. I have. The valve stem 3a is inserted into the guide hole 14, and a coil spring 32 as a "valve closing spring" is disposed between the flange 3c and the spring receiver 31 at the bottom of the valve chamber 1A. Thereby, the coil spring 32 urges the valve body 3 toward the diaphragm 43 described later.

  An operation section 4 is attached to the valve housing 1 on the side opposite to the valve chamber 1A. The operation unit 4 includes a lower lid 41 fixed to the valve housing 1, an upper case 42 having the same diameter as the lower lid 41, a diaphragm 43 disposed between the lower lid 41 and the upper case 42, and a lower lid 41. And a lower support 44 disposed between the diaphragm 43 and the valve rod 3a of the valve body 3 and a upper support 45 disposed above the diaphragm 43 in the upper case 42. The lower lid 41, the diaphragm 43, and the upper case 42 are welded at the outer peripheral edge and are integrally joined. As shown in the top view of FIG. 2, the valve housing 1 is rectangular, but the upper case 42 (and the lower lid 41, the diaphragm 43) and the thermoelement 20 are rotationally symmetric about the axis L.

  The lower abutment 44 has a larger diameter than the outer diameter of the valve stem 3a. Thus, as described later, when the diaphragm 43 is deformed by the action of the thermoelement 20 to transmit the pressing force to the valve rod 3a, the reaction force received from the valve rod 3a is applied to the diaphragm 43 over a large area of the lower support 44. And the durability of the diaphragm 43 can be improved. Similarly, the upper support 45 has a larger diameter than the outer diameter of the piston 23 described later. Thus, the pressing force can be dispersed and transmitted to the diaphragm 43 over a wider area of the upper support 45 than when the piston 23 directly contacts the diaphragm 43, and the durability of the diaphragm 43 can be improved.

  As a result, the operation unit 4 allows the diaphragm 43 and the lower lid 41 to hermetically seal the structure of the lower arm 44 and the valve stem 3a, and also allows the diaphragm 43 and the lower lid 41 to move from the upper arm 45 in the upper case 42 to the outside of the diaphragm 43. It has a function of transmitting a mechanical pressing force in the direction of the axis L to the valve element 3 (valve rod 3 a) via the diaphragm 43 and the lower support 44. The thermoelement 20 (part thereof) is accommodated in the cylindrical portion 42a of the upper case 42 of the operation unit 4, and the thermosensitive element 21a of the thermoelement 20 projects from the upper end of the upper case 42, and the thermoelement 20 An engagement piece 42a1 at the end of the cylindrical portion 42a is engaged with an end of the temperature-sensing portion-side base 21b on the temperature-sensing portion 21a side.

  The thermoelement 20 is a thermoactuator utilizing expansion and contraction of paraffin or the like due to a temperature change. As shown in FIG. 3, the thermoelement 20 includes a temperature-sensitive case 21, a guide case 22, a piston 23, a diaphragm 24, a rubber piston 25, and a protection plate 26. The temperature sensing case 21 includes a cylindrical temperature sensing portion 21 a having a bottom at an end portion, and a temperature sensing portion side base 21 b covering a part of the guide case 22. The guide case 22 includes a cylindrical guide portion 22a in which the piston 23, the rubber piston 25, and the protection plate 26 are inserted, and a guide side base portion 22b covered by the temperature sensing portion side base portion 21b of the temperature sensing case 21. I have.

  Mainly in the temperature-sensitive portion 21a of the temperature-sensitive case 21, a thermal expansion body 2A made of wax such as paraffin is filled, and a lower end surface of the thermal expansion body 2A is sealed by a diaphragm 24 which is an elastic sealing member. I have. A fluid chamber is provided between the mortar-shaped inner surface 22b1 of the guide-side base 22b of the guide case 22 and the lower side of the diaphragm 24, and the fluid chamber is filled with a fluid 2B. The fluid 2B is a non-compressible fluid that is incompressible and has good fluidity and lubricity. A piston 23 is slidably inserted into a piston sliding hole 22a1 inside the guide portion 22a of the guide case 22 via a rubber piston 25 and a protection plate 26, and the outer end of the piston 23 is It protrudes from the moving hole 22a1.

  When the environmental temperature of the temperature sensing section 21a rises, the thermal expansion body 2A expands and the diaphragm 24 expands, pushing down the fluid 2B sealed in the fluid chamber below the diaphragm 24. As a result, the fluid 2B is deformed and a part of the fluid 2B enters the piston sliding hole 22a1 of the guide portion 22a, and pushes down the piston 23 via the rubber piston 25 and the protection plate 26.

  As shown in FIG. 1, a play hole 45 a, a guide insertion hole 45 b, and a spring receiving hole 45 c are formed coaxially in the upper support 45, and the piston 23 of the thermoelement 20 faces the play hole 45 a, The guide portion 22a is inserted into the guide insertion hole 45b. A fixed spring 46 is provided on the outer periphery of the guide portion 22a. The fixed spring 46 is provided by being compressed between the temperature-sensitive-portion-side base 21b in the cylindrical portion 42a and the bottom of the spring accommodating hole 45c. Have been. That is, as described above, since the end of the temperature sensing portion side base 21b is engaged with the locking piece 42a1 of the cylindrical portion 42a, the thermoelement 20 is fixed to the cylindrical portion 42a by the spring force of the fixed spring 46. ing. Further, the temperature sensing portion 21a of the thermoelement 20 projects in a cylindrical shape, and has a structure that can be easily mounted on a temperature sensing target. The temperature sensing portion 21a is mounted in the mounting hole 50a of the metal plate 50, and heat from the metal plate 50 is transmitted to the temperature sensing portion 21a. The metal plate 50 is in close contact with a heat source (not shown).

  With the above configuration, when the temperature of the temperature sensing portion 21a of the thermoelement 20 rises from the state of FIG. 1 and the piston 23 descends as described above, the piston 23 comes into contact with the upper support 45 (the bottom of the play hole 45a). . Further, when the piston 23 descends, the upper pad 45 descends, the diaphragm 43 is deformed, the lower pad 44 descends, and the valve body 3 in contact with the lower pad 44 descends. As described above, in this embodiment, the moment when the pressing force of the piston 23 starts to be applied to the valve element 3 via the upper pad 45, the diaphragm 43 and the lower pad 44 is the “valve opening point”, and this valve opening point Then, the needle portion 3b of the valve body 3 is separated from the periphery of the valve port 13 to open the valve port 13.

  FIG. 4 is a diagram showing a temperature-displacement characteristic showing a relationship between the temperature of the temperature sensing portion 21a in the thermoelement 20 and the displacement (lift) of the piston 23. The thermal expansion body 2A in the temperature sensing part 21a changes its phase according to the temperature, such as a solid state, a solid-liquid mixed state in which a solid and a liquid are mixed, and a liquid state. Thus, the temperature-displacement characteristics include a “solid expansion region” that expands in a solid state, a “solid-liquid mixed expansion region” that expands in a solid-liquid mixed state, and a “liquid expansion region” that expands in a liquid state. Each has a different slope. Then, the gradient in the solid-liquid mixed expansion region, that is, the temperature expansion coefficient becomes the largest (steep). This temperature-displacement characteristic is known as a characteristic unique to the thermoelement 20, and in this case, the range of the lifts L1 to L3 of the piston 23 corresponds to the "solid-liquid mixed expansion region".

  Here, as described above, the valve opening point in the valve device main body 10 is set so as to be within the range of the “solid-liquid mixed expansion area”. In this embodiment, the valve opening point is set in a state where “valve opening lift = 0” and “thermo element lift = L2” shown in FIG. As described above, since the valve opening point is set within the range of the “solid-liquid mixed expansion area” where the thermal expansion coefficient of the thermal expansion body 2A in the thermoelement 20 is large, when the heat source reaches the set temperature, the valve port 13 can be quickly opened widely. Thereby, the refrigerant can be quickly supplied to the cooling device (not shown) following the temperature change of the heat source, and as a result, the heat source can be rapidly cooled.

  In the thermoelement 20, when the temperature of the temperature sensing portion 21a decreases and the thermal expansion body 2A contracts, a vacuum gap is formed in the thermal expansion body 2A solidified without moving the diaphragm 24, or a fluid is formed. A void may be formed in 2B. Further, the diaphragm 24 may be deformed due to contraction in the thermal expansion body 2A, and the fluid 2B may also change its shape. In such a case, with the piston 23 protruding, the rubber piston 25 and the protection plate 26 are also stopped on the piston 23 side, or only the rubber piston 25 is moved following the fluid 2B. In some cases, the rubber piston 25 and the protection plate 26 may move to follow the moving body 2B. In any case, when the piston 23 protrudes and stops, the piston 23 does not apply a pressing force to the operating portion 4 (or the valve body 3), and is different from the “valve opening point” in the present invention. State.

  Here, in the operation unit 4, when the valve is closed by the valve body 3 as shown in FIGS. 1 and 2, the diaphragm 43 applies the tension of the diaphragm 43 to the valve body 3 (valve rod 3a) via the lower paddle 44. The force in the direction of the axis L due to this tension urges the valve body 3 in the valve opening direction. FIG. 5 is a diagram showing the structure of the diaphragm, and FIG. 5 (A) shows a state where the diaphragm 43 is in an initial single state before being incorporated into the operation unit 4 (natural state), that is, a load is applied to the diaphragm 43. FIG. 5B is a cross-sectional view showing the state of the diaphragm 43 when the valve is closed when the valve 43 is assembled into the operation unit 4, and the two-dot chain line indicates the upper pad 45 and the lower pad. 44 is shown.

  As shown in FIG. 5 (A), the diaphragm 43 is formed of a thin film metal ring and has a flange portion 43b having flat flange surfaces 43b1 and 43b2 at the outer peripheral portion, and a top plate 45 at the center portion. A contact portion 43a having a flat working surface 43a2 and a flat working surface 43a1 abutting on the lower abutment 44 is formed, respectively, between the flange portion 43b of the outer peripheral portion and the contact portion 43a of the central portion. Is formed with a wavy annular portion 43c. The operation surface 43a1 that comes into contact with the lower abutment 44 of the contact portion 43a is an "operation surface" that transmits mechanical pressing force in the axial direction to the valve body 3 via the diaphragm 43.

  Here, in a natural state before the diaphragm 43 is incorporated into the operation unit, the operation surface 43a1 at the center is at a position lower than the flange surface 43b1 at the outer periphery. Next, when the diaphragm 43 is incorporated into the operation unit, the corrugated annular portion 43c is deformed at the valve closed position, as shown in FIG. 5 (B), so that the central working surface 43a1 becomes the outer peripheral flange surface. It is incorporated at a position higher than 43b1. That is, the position of the action surface 43a1 is higher than the position of the natural state in FIG. As a result, a downward tension is generated on the diaphragm 43 when the valve is closed, and this tension acts on the valve body in the valve opening direction. When the force of the piston 23 is not applied from the thermoelement 20, the spring force of the coil spring 32 as the "valve closing spring" is set to maintain the valve closed state against the tension of the diaphragm 43. ing. The shape of the diaphragm 43 is not limited to the embodiment shown in FIGS. 5A and 5B, and may be any structure as long as the diaphragm tension acts in the valve opening direction when the valve is closed.

  Since the diaphragm 43 urges the valve body 3 in the valve opening direction in the assembled state, as shown in FIG. 6, the temperature sensed by the temperature sensing portion 21a of the thermoelement 20 and the valve of the valve body 3 The characteristic with the lift (valve opening) becomes steeper than before. Therefore, when the valve is in the open state, the refrigerant can flow quickly through the valve port 13, and the refrigerant can be quickly supplied to the cooling device, etc., following the temperature change of the heat source, and the heat source can be quickly cooled. Can be. Further, the tension of the diaphragm 43 exerts a force in the same direction as the pressing force of the piston 23 of the thermoelement 20, so that an unnecessary load is not applied to the stroke of the piston 23 of the thermoelement 20, and the durability of the thermoelement 20 is reduced. The performance is also improved.

  Further, in the embodiment, the lower portion of the diaphragm 43, that is, the surface on the lower lid 41 side receives the low pressure of the second port 12 from which the refrigerant flows out, so that the diaphragm 43 is further easily displaced in the valve opening direction. This allows the refrigerant to flow more quickly at a larger flow rate.

  Further, in the embodiment, a case where the height of the working surface of the pressing force of the diaphragm after assembly is the height in the natural state is the liquid expansion area of the thermal expansion body 2A in the temperature sensing part 21a of the thermoelement 20. 4 and FIG. 6, the lift of the inflection point in the temperature-valve lift characteristic between the solid-liquid mixed expansion region and the liquid expansion region of the thermal expansion body 2A (characteristic A in FIGS. 4 and 6). At the position of the lift larger than (temperature), the diaphragm 43 becomes the “position in a natural state” of the diaphragm 43. Even at a temperature after this inflection point, the tension in the valve opening direction of the diaphragm 43 acts. -The valve lift characteristics can be kept steep, and the refrigerant can flow at a large flow rate more quickly.

  On the other hand, in the embodiment, the region where the height of the working surface of the pressing force of the assembled diaphragm becomes the height in the natural state is defined as the solid-liquid mixed expansion of the thermal expansion body 2A in the thermosensitive portion 21a of the thermoelement 20. The temperature-lift characteristic in the case where the diaphragm 43 is located at a lift position smaller than the lift at the inflection point in the temperature-valve lift characteristic as shown in the characteristic B of FIG. , The tension in the valve closing direction of the diaphragm 43 acts at a temperature thereafter, and the slope of the temperature-valve lift characteristic is slightly looser than that of the characteristic A. Better than the characteristics.

  Although the thermoelement in the embodiment includes the rubber piston, the protection plate, and the fluid, these may not be provided. The thermoelement only needs to transmit the volume change of the thermal expansion body to the piston.

  As described above, the embodiments of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to these embodiments, and a design change or the like may be made without departing from the scope of the present invention. The present invention is also included in the present invention.

  For example, the valve body is not limited to the one in which the valve body contacts the valve seat around the valve port and completely closes the valve port.There is a gap or a flow path between the valve body and the valve seat, and there is a slight bleed flow rate. May be the case. That is, in the present invention, the “closed state” of the valve port is a concept including a case where the valve port is completely closed and a case where there is a bleed flow rate.

1 Valve Housing 1A Valve Chamber 11 First Port 12 Second Port 13 Valve Port 14 Guide Hole L Axis 21 Temperature Sensing Case 21a Temperature Sensing Part 21b Temperature Sensing Part Side Base 22 Guide Case 22a Guide Part 22b Guide Side Base 23 Piston 24 Diaphragm 25 Rubber piston 26 Protective plate 2A Thermal expansion body 2B Fluid 3 Valve body 3a Valve rod 3b Needle part 3c Flange part 3a 'Valve rod 31 Spring receiver 32 Coil spring 4 Operating part 41 Lower lid 42 Upper case 42a Cylindrical part 43 Diaphragm 43a1 Working surface (Working surface of pressing force)
44 Lower allowance (valve body allowance)
45 Allowance (Piston side allowance)
46 Fixed spring 47 Coil spring 45a Play hole 45b Guide insertion hole 45c Spring receiving hole 10 Valve device main body 20 Thermoelement 100 Temperature-sensitive control valve

Claims (3)

A thermo element for moving the piston in the axial direction by a volume change of the thermal expansion body which expands and contracts in accordance with a temperature change;
A valve device body that opens and closes a valve port through which a refrigerant flows in a valve body urged in a valve closing direction by a valve closing spring, wherein a structure including the valve body is hermetically sealed by a diaphragm, and A valve device main body having an operating unit for transmitting a mechanical pressing force in the axial direction to the valve body via the diaphragm in the axial direction,
With
The diaphragm is configured such that the height of the working surface of the diaphragm that urges the pressing force when the valve is closed by the valve body is higher than the working surface of the diaphragm in the natural state. Temperature-sensitive control valve. The valve device body has a valve housing, a valve chamber is formed in the valve housing, and a first port through which the refrigerant flows into the valve chamber and a refrigerant from the valve chamber are formed on a side wall of the valve housing. A second port that flows out is formed, and the valve port is formed in the axial direction between the valve chamber and the second port;
The temperature-sensitive control valve according to claim 1, wherein the operation unit is provided on an upper part of the valve device main body, and a lower part of the diaphragm communicates with the second port.   2. The temperature-valve lift characteristic, wherein a region where the height of the working surface of the diaphragm is a height in a natural state is a liquid expansion region of a thermal expansion body in a thermosensitive part of the thermoelement. 2. The temperature-sensitive control valve according to item 1.

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