JP2015001318A - Expansion valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an expansion valve capable of taking a countermeasure to a flowing sound with a simple configuration.SOLUTION: An expansion valve 10 leads out a refrigerant introduced from the upstream side of a refrigeration cycle to the downstream side while throttling and expanding the same by making the refrigerant pass through a valve portion 40 in a body 11. The expansion valve 10 includes: an introduction port 13 formed as a bottomed hole opened to a side face of the body 11; a refrigerant passage 17 penetrating through the body 11, connected to a bottom portion of the introduction port 13 at one end side, and provided with the valve portion 40 on its intermediate portion; and a projecting portion 14 integrally formed as a part of the body 11 while projecting to the opening side from a bottom surface 13a of the introduction port 13, and forming a part of the refrigerant passage 17 at its inner side.

Description

  The present invention relates to an expansion valve that squeezes and expands a high-temperature and high-pressure refrigerant introduced from the upstream side to produce a low-temperature and low-pressure refrigerant downstream.

  In general, a refrigeration cycle of an automotive air conditioner is provided with a compressor, a condenser, an expansion valve, and an evaporator. The refrigerant circulating in the refrigeration cycle is compressed by a compressor, and the compressed refrigerant is condensed by a condenser. The condensed refrigerant is squeezed and expanded by an expansion valve and is led out as a mist. The mist refrigerant is evaporated by an evaporator, and the air in the passenger compartment is cooled by the latent heat of evaporation accompanying the evaporation.

  Normally, liquid refrigerant is introduced into the expansion valve. However, depending on operating conditions such as a compressor and temperature conditions such as outside air temperature, a gas-liquid two-phase refrigerant in which bubbles are mixed in the liquid may be introduced. . When such a refrigerant mixed with air bubbles passes through the valve portion of the expansion valve, a flow noise is intermittently generated, so that countermeasures are required.

  Patent Document 1 proposes an expansion valve in which a throttle part is inserted into a pipe inserted into an introduction port. This expansion valve is designed to reduce flow noise by reducing the bubbles in the refrigerant by inserting a throttle part and providing a throttle part.

JP 2004-101082 A

  The present inventor has examined the structure of an expansion valve that can realize a countermeasure against flow noise with a simple configuration, and has come to recognize that there is room for improvement over the conventional structure.

  This invention is made | formed in view of such a subject, and one of the objectives is to provide the expansion valve which can implement | achieve a flow noise countermeasure with a simple structure.

  In order to solve the above-described problem, an aspect of the present invention relates to an expansion valve that expands a refrigerant introduced from the upstream side of a refrigeration cycle by passing through a valve portion in the body and leads the refrigerant to a downstream side. The expansion valve has an introduction port formed as a bottomed hole that opens on the side surface of the body, and is formed so as to penetrate the body. One end side of the expansion valve is connected to the bottom of the introduction port, and a valve portion is provided at an intermediate portion thereof. A refrigerant passage, and a protrusion that protrudes from the bottom surface of the introduction port to the opening side and is integrally formed as a part of the body, and a part of the refrigerant passage is formed inside the refrigerant passage.

  According to an aspect of the present invention, a protrusion having a part of the refrigerant passage formed therein is provided. If the diameter-reduced portion whose inner diameter is smaller than the inner diameter of the introduction tube inserted into the introduction port is formed from the tip side of the projection, it is preferable that the diameter-reduced portion becomes longer by the length of the projection. The flow noise reduction effect can be obtained, and the flow noise countermeasure can be realized with a simple configuration.

  According to the present invention, it is possible to realize a countermeasure against flowing sound with a simple configuration.

It is front sectional drawing which shows the structure of the expansion valve which concerns on 1st Embodiment. It is a left side sectional view showing the composition of the expansion valve concerning a 1st embodiment. It is an enlarged view which shows the state which inserted the introduction pipe | tube in the lower side introduction port of the expansion valve which concerns on 1st Embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description, for the sake of convenience, the positional relationship of each component may be expressed based on the illustrated state.

[First Embodiment]
1 and 2 show a configuration of an expansion valve 10 according to the first embodiment. FIG. 1 is a front sectional view of the expansion valve 10. FIG. 2 is a left side cross-sectional view of the expansion valve 10 and shows a cross-sectional view taken along line AA of FIG. The expansion valve 10 according to the first embodiment is used in a refrigeration cycle 100 of an automotive air conditioner. In addition to the expansion valve 10, the refrigeration cycle 100 includes a compressor 101, a condenser 103, and an evaporator 105. The refrigerant circulating in the refrigeration cycle 100 is compressed by the compressor 101, and the compressed refrigerant is condensed by the condenser 103. The condensed liquid refrigerant is squeezed and expanded by the expansion valve 10 to be discharged as a mist, and the mist refrigerant is evaporated by the evaporator 105, and the air in the passenger compartment is cooled by the latent heat of evaporation accompanying the evaporation. .

  In the first embodiment, the expansion valve 10 senses the temperature and pressure of the refrigerant from the evaporator 105 toward the compressor 101 and operates autonomously, and controls the flow rate of the refrigerant from the condenser 103 toward the evaporator 105. Configured as a mechanical expansion valve to adjust.

  The expansion valve 10 includes a body 11. The body 11 is formed by performing cutting or the like on an intermediate molded product obtained by extrusion molding or the like of a metal material such as an aluminum alloy. The body 11 is formed in a prismatic shape in the first embodiment, and a valve portion 40 that performs throttle expansion of the refrigerant is provided therein. A power element 60 that functions as a temperature sensing unit and a cover 61 that covers the power element 60 from the outside are provided at an end (upper end) in the longitudinal direction of the body 11.

  The expansion valve 10 includes a lower inlet port 13 and a lower outlet port 15 provided on the side of the body 11, and a lower refrigerant passage 17 formed inside the body 11 so as to penetrate the body 11. The lower introduction port 13 is formed as a stepped bottomed hole that opens at a lower portion of the front side surface (right side surface in FIG. 2) of the body 11, and a bottom surface 13a is provided on the back side. The lower lead-out port 15 is formed to open at the lower part of the left side surface (the left side surface in FIG. 1) of the body 11. The lower refrigerant passage 17 connects the bottom portion of the lower introduction port 13 and the lower outlet port 15. That is, the lower refrigerant passage 17 has one end connected to the bottom of the lower introduction port 13 and the other end connected to the lower outlet port 15. Further, the lower refrigerant passage 17 is provided with a valve portion 40 at an intermediate portion thereof.

  The lower introduction port 13 introduces a high-temperature, high-pressure liquid refrigerant from the condenser 103 side. The valve section 40 causes the liquid refrigerant introduced from the lower introduction port 13 to be swelled and expanded into a mist by passing through the valve section 40, and is led out toward the lower outlet port 15. The lower lead-out port 15 guides the low-temperature and low-pressure mist-like refrigerant that has been throttled and expanded by the expansion valve 10 toward the evaporator 105 side.

  The expansion valve 10 includes an upper inlet port 31 and an upper outlet port 33 provided on the side portion of the body 11, and an upper refrigerant passage 35 formed inside the body 11 so as to penetrate the body 11. The upper introduction port 31 is formed to open at the upper part of the left side surface (the left side surface in FIG. 1) of the body 11. The upper outlet port 33 is formed to open at the upper part of the front side surface (the right side surface in FIG. 2) of the body 11. The upper refrigerant passage 35 connects the upper introduction port 31 and the upper outlet port 33. The upper introduction port 31 introduces the refrigerant evaporated by the evaporator 105. The upper outlet port 33 introduces the refrigerant introduced from the upper inlet port 31 and passing through the upper refrigerant passage 35 to the compressor 101 side.

  The valve unit 40 includes a valve hole 41, a valve seat 43, and a valve body 45. The valve hole 41 is formed in an intermediate portion of the lower refrigerant passage 17 of the body 11, and the valve seat 43 is formed by an opening edge on the lower introduction port 13 side of the valve hole 41. The valve body 45 is formed in a ball shape, and is disposed to face the valve seat 43 from the lower introduction port 13 side.

  The expansion valve 10 is formed in the body 11 and includes a lower communication hole 19 that communicates the lower refrigerant passage 17 with the inside and outside. An adjustment screw 51 as an adjustment member is screwed into the body 11 so as to seal the lower communication hole 19. The lower communication hole 19 is formed with a valve chamber 21 that accommodates the valve body 45 by an upper half that is a part of the lower communication hole 19. The valve body 45 is supported from below by a support member 52 accommodated in the valve chamber 21, and a biasing member that biases the valve body 45 in the valve closing direction between the support member 52 and the adjustment screw 51. As a spring 53 is interposed. An O-ring 54 is interposed between the adjustment screw 51 and the body 11 to prevent the refrigerant from leaking to the outside.

  The expansion valve 10 includes a communication channel 23 formed between the valve chamber 21 and the lower introduction port 13 inside the body 11. The communication channel 23 is formed such that one end side opens to the lower introduction port 13 and the other end side opens to the valve chamber 21. The communication channel 23 has an inner diameter smaller than the inner diameter of the lower introduction port 13. The valve chamber 21 communicates with the lower introduction port 13 through the communication flow path 23 on the upstream side, and communicates with the valve hole 41 on the downstream side thereof. The lower refrigerant passage 17 includes the communication passage 23 and the valve chamber 21.

  The expansion valve 10 is formed in the body 11 and includes an upper communication hole 37 that allows the upper refrigerant passage 35 to communicate with the inside and outside. A power element 60 is screwed into the body 11 so as to seal the upper communication hole 37. The power element 60 includes an upper housing 63, a lower housing 65, a diaphragm 67 formed of a thin metal plate or the like sandwiched between them, and a disk 69 disposed on the lower housing 65 side. . A temperature-sensitive gas is enclosed in a sealed space surrounded by the upper housing 63 and the diaphragm 67. An O-ring 71 is interposed between the power element 60 and the body 11 to prevent refrigerant leakage. The pressure and temperature of the refrigerant passing through the upper refrigerant passage 35 are transmitted to the lower surface of the diaphragm 67 through the upper communication hole 37 and a hole (not shown) provided in the disk 69.

  The body 11 is provided with a stepped hole 25 for connecting the lower refrigerant passage 17 and the upper refrigerant passage 35 therein, and a columnar shaft 55 is slidable in a small diameter portion of the stepped hole 25. It is inserted. The shaft 55 is interposed between the disc 69 and the valve body 45. As a result, the driving force associated with the displacement of the diaphragm 67 is transmitted to the valve body 45 via the disk 69 and the shaft 55. An O-ring 56 is disposed in the large diameter portion of the stepped hole 25 so that the shaft 55 is inserted inside, and leakage of the refrigerant between the lower refrigerant passage 17 and the upper refrigerant passage 35 is prevented. The upper portion of the shaft 55 is inserted inside the cylindrical holder 57. A spring 53 that applies a predetermined lateral load to the shaft 55 is interposed between the holder 57 and the shaft 55, and the vibration of the shaft 55 due to a change in refrigerant pressure is suppressed by the lateral load.

  In the expansion valve 10 configured as described above, the refrigerant is introduced from the evaporator 105 through the upper introduction port 31, and the pressure and temperature of the refrigerant are detected by the power element 60, so that the diaphragm 67 is displaced. The displacement of the diaphragm 67 becomes a driving force, which is transmitted to the valve body 45 through the disk 69 and the shaft 55, and the valve portion 40 is opened and closed by the movement of the valve body 45. On the other hand, liquid refrigerant is introduced from the condenser 103 side through the lower introduction port 13 and is squeezed and expanded by passing through the valve portion 40 to become a low-temperature, low-pressure mist refrigerant. The atomized refrigerant is led out toward the evaporator 105 through the lower lead-out port 15. At this time, the opening degree of the valve unit 40 is adjusted by the movement of the valve body 45, and the flow rate of the refrigerant from the condenser 103 toward the evaporator 105 is adjusted.

  FIG. 3 is an enlarged view showing a state in which the introduction pipe 110 is inserted into the lower introduction port 13 of the expansion valve 10 according to the first embodiment. A distal end portion 111 of an introduction pipe 110 for introducing the refrigerant into the lower refrigerant passage 17 can be inserted into the lower introduction port 13. The introduction pipe 110 is caulked in the axial direction to form a flange portion 113 that protrudes radially outward. The introduction pipe 110 is restricted from being further inserted by engaging the flange 113 with the step portion of the lower introduction port 13 as a stepped bottomed hole. When the introduction pipe 110 is inserted into the lower introduction port 13 and the expansion valve 10 is in an insertion restriction position where the insertion is restricted, the distal end surface 111a of the introduction pipe 110 and the bottom face 13a of the lower introduction port 13 are arranged. It is configured to be provided at intervals.

  A plate-like fixing member 120 for fixing the introduction tube 110 is disposed in contact with the side portion of the body 11. The fixing member 120 is formed with a through hole 121 through which the introduction tube 110 is inserted. The introduction pipe 110 is disposed so that the flange portion 113 is sandwiched between the fixing member 120 and the stepped portion of the lower introduction port 13, and is fixed by connecting the fixing member 120 to the body 11 with a screw or the like. The An O-ring 123 is interposed between the introduction pipe 110 and the lower introduction port 13 to prevent leakage of the refrigerant to the outside.

  Here, the expansion valve 10 according to the first embodiment includes a protruding portion 14 that protrudes from the bottom surface 13 a of the lower introduction port 13 toward the opening 13 b and is integrally formed as a part of the body 11. The protrusion 14 is formed in a substantially circular cylindrical shape in the first embodiment.

  A part of the communication channel 23 which is a part of the lower refrigerant passage 17 is formed inside the protrusion 14. This communication flow path 23 is formed as a reduced diameter portion 27 whose inner diameter R2 is smaller than the inner diameter R1 of the introduction pipe 110 in the range from the tip of the protruding portion 14 to the valve chamber 21. Thereby, the bubbles in the liquid refrigerant introduced from the condenser 103 side through the introduction pipe 110 are reduced or refined when passing through the reduced diameter portion 27, and the flow generated when the bubbles pass through the valve portion 40. Sound can be reduced.

  In addition, in the first embodiment, the introduction pipe 110 has an inner diameter and an outer diameter between the flange portion 113 and the distal end portion 111 in order to secure a space in which the O-ring 123 is interposed. A smaller diameter portion 112 having a smaller diameter is provided. In the first embodiment, the reduced diameter portion 27 of the lower refrigerant passage 17 has an inner diameter R2 smaller than the inner diameter R1 of the small diameter portion 112 having the narrowest inner diameter of the introduction pipe 110.

  As the length of the reduced diameter portion 27 is longer, a better flow noise reduction effect is obtained. The inner diameter R2 and the length dimension of the reduced diameter portion 27 can be appropriately set by obtaining, for example, an experiment or an analysis on the conditions for obtaining a desired flow noise reduction effect. As for these dimensions, for example, when the inner diameter R2 is 2.5 to 4.0 mm and the length is 3.0 mm or more, a good flow noise reduction effect can be obtained.

  The range formed as the reduced diameter portion 27 is not limited to the range from the tip of the protruding portion 14 to the valve chamber 21 as in the first embodiment. If the range of the reduced diameter portion 27 is a range including at least the inside of the protruding portion 14 in the range from the front end side to the other end side of the lower refrigerant passage 17, for example, the communication flow path from the front end of the protruding portion 14. The range up to the middle part of 23 may be sufficient.

  The expansion valve 10 includes a bubble storage chamber 28 formed between the outer peripheral surface 14 a of the protruding portion 14 and the inner peripheral surface 13 c of the lower introduction port 13. In the first embodiment, the bubble storage chamber 28 is formed as an annular space surrounding the outer peripheral side of the protrusion 14. The bubble storage chamber 28 is formed on the body 11 by cutting a portion corresponding to the bubble storage chamber 28 while leaving a portion to be the protruding portion 14.

  The protruding portion 14 is formed so that the outer diameter R4 is smaller than the inner diameter R3 of the distal end portion 111 of the introduction tube 110. The projecting portion 14 is configured to be arranged coaxially with respect to the distal end portion 111 of the introduction tube 110 when the introduction tube 110 is inserted into the lower introduction port 13. In the first embodiment, the protruding portion 14 is inserted into the inside of the tip portion 111 of the introduction tube 110, and a range that overlaps with the introduction tube 110 in the axial direction is provided. A gap 29 is formed between the inner peripheral surface 111 b of the distal end portion 111 of the introduction pipe 110 and the outer peripheral face 14 a of the protrusion 14, and the inside of the introduction pipe 110 and the bubble storage chamber 28 are communicated with each other through the gap 29. The Bubbles in the refrigerant passing through the introduction pipe 110 are introduced into the bubble storage chamber 28 through the gap 29. In this way, the expansion valve 10 can introduce bubbles in the refrigerant passing through the introduction pipe 110 into the bubble storage chamber 28 when the introduction pipe 110 is inserted into the lower introduction port 13. Composed. The protruding portion 14 does not need to have a range where the tip end portion is inserted into the inside of the introduction tube 110 and overlaps with the introduction tube 110 in the axial direction.

  By providing the bubble storage chamber 28 in the expansion valve 10, at least part of the bubbles passing through the introduction pipe 110 is introduced into the bubble storage chamber 28 before passing through the lower refrigerant passage 17 including the valve portion 40. And trapped, and the generation of flow noise due to the passage of bubbles through the valve portion 40 is suppressed. The air bubbles introduced into the air bubble storage chamber 28 are temporarily stored in the air bubble storage chamber 28, but are liquefied due to high temperature and high pressure conditions, and are introduced into the lower refrigerant passage 17 as liquid refrigerant.

  As the volume of the bubble storage chamber 28 increases, the amount of bubbles stored increases, and the introduction of the bubbles temporarily stored in the bubble storage chamber 28 into the lower refrigerant passage 17 is suppressed, and the generation of flow noise is generated. It is suppressed. In the expansion valve 10 according to the first embodiment, the distal end surface 111a of the introduction pipe 110 and the bottom surface 13a of the lower introduction port 13 are provided with an interval from the viewpoint of securing the amount of bubbles stored in the bubble storage chamber 28. It is configured to be. The volume of the bubble storage chamber 28 may be adjusted so that the amount of bubbles liquefied in the bubble storage chamber 28 is larger than the amount of bubbles introduced into the bubble storage chamber 28. This dimensional condition can be appropriately set by obtaining it by experiment or analysis.

  According to the expansion valve 10 which concerns on 1st Embodiment, the protrusion part 14 in which a part of lower refrigerant path 17 was formed in the inner side is provided. If the reduced diameter portion 27 is formed from the front end side of the protruding portion 14, the reduced diameter portion 27 becomes longer by the length of the protruding portion 14, so that a good flow noise reduction effect can be obtained and simplified. Flow noise countermeasures can be realized by the configuration. In particular, since the protruding portion 14 is integrally formed as a part of the body 11 and there is no need to use a separate component from the body 11, it is possible to realize a countermeasure against flowing sound while suppressing the number of components and the number of assembly steps.

  Further, the reduced diameter portion 27 can be increased by the length of the protruding portion 14 without changing the dimensions of the body 11 and the valve chamber 21 and the depth dimension of the lower introduction port 13 (the left and right dimensions in FIG. 3). Become. In order to lengthen the reduced diameter portion 27, for example, the width dimension of the body 11 (left and right dimensions in FIG. 3) may be increased to lengthen the communication flow path 23. However, if the width dimension of the body 11 is increased. Material costs increase. On the other hand, according to the expansion valve 10 according to the first embodiment, since it is not necessary to change the dimensions of the body 11 and the like, it is preferable to lengthen the reduced diameter portion 27 without increasing the material cost of the body 11. It is possible to obtain an effective flow noise reduction effect.

  As mentioned above, although this invention was demonstrated based on embodiment, embodiment only shows the principle and application of this invention. In the embodiment, many modifications and arrangements can be made without departing from the spirit of the present invention defined in the claims.

  In the above-described embodiment, the example in which the diaphragm is used as the pressure-sensitive member that senses the pressure and temperature of the refrigerant introduced from the evaporator 105 has been described. As the pressure sensitive member, a member that senses pressure and expands and contracts, such as a bellows, may be used.

  In the above-described embodiment, the mechanical expansion valve that autonomously adjusts the opening degree of the valve unit 40 by driving the power element 60 has been described as the expansion valve 10. However, the valve unit is opened from the outside by electrical control. An electromagnetic expansion valve that adjusts the degree may be used.

DESCRIPTION OF SYMBOLS 10 Expansion valve, 11 Body, 13 Lower introduction port, 13a Bottom surface, 13b Opening, 13c Inner peripheral surface, 14 Protruding part, 14a Outer peripheral surface, 15 Lower deriving port, 17 Lower refrigerant passage, 19 Lower communication hole, 21 valve chamber, 23 communication channel, 28 bubble storage chamber, 29 gap, 40 valve portion, 41 valve hole, 43 valve seat, 45 valve body, 60 power element, 100 refrigeration cycle, 101 compressor, 103 condenser, 105 Evaporator, 110 introduction pipe, 111 tip, 111a tip, 111b inner peripheral surface, 113 flange, 120 fixing member.

Claims (5)

An expansion valve that squeezes and expands the refrigerant introduced from the upstream side of the refrigeration cycle by passing it through the valve part in the body and leads it to the downstream side,
An introduction port formed as a bottomed hole that opens in a side surface of the body;
A refrigerant passage formed so as to penetrate the body, one end side of which is connected to the bottom portion of the introduction port, and the valve portion is provided in an intermediate portion thereof;
An expansion valve comprising: a protruding portion that protrudes from the bottom surface of the introduction port to the opening side and is integrally formed as a part of the body and in which a part of the refrigerant passage is formed. An introduction pipe for introducing a refrigerant into the refrigerant passage can be inserted into the introduction port,
When the introduction pipe is inserted into the introduction port, bubbles in the refrigerant passing through the introduction pipe can be introduced into the bubble storage chamber formed between the outer peripheral surface of the projecting portion and the introduction port. The expansion valve according to claim 1, wherein the expansion valve is configured as follows. An introduction pipe for introducing a refrigerant into the refrigerant passage can be inserted into the introduction port,
The protrusion is formed so that its outer diameter is smaller than the inner diameter of the distal end of the introduction tube, and is coaxial with the distal end of the introduction tube when the introduction tube is inserted into the introduction port. The expansion valve according to claim 1, wherein the expansion valve is configured to be arranged. An introduction pipe for introducing a refrigerant into the refrigerant passage can be inserted into the introduction port,
4. The structure according to claim 1, wherein when the introduction tube is inserted into the introduction port, the leading end surface of the introduction tube and the bottom surface of the introduction port are provided with a space therebetween. An expansion valve according to claim 1. An introduction pipe for introducing a refrigerant into the refrigerant passage can be inserted into the introduction port,
The refrigerant passage is formed such that a range including at least the inside of the projecting portion is formed as a reduced diameter portion whose inner diameter is smaller than the inner diameter of the introduction pipe in a range from the front end side to the other end side. The expansion valve according to any one of claims 1 to 4, characterized in that:

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