JP4588656B2 - Expansion valve with integrated solenoid valve - Google Patents

Description

  The present invention relates to an electromagnetic valve-integrated expansion valve, and is suitable for use in, for example, a vehicle air conditioner in which a refrigeration cycle is provided on the front side and rear side of a vehicle interior.

2. Description of the Related Art Conventionally, as this type of solenoid valve-integrated expansion valve, for example, the one described in Patent Document 1 below is known. This expansion valve integrated with a solenoid valve includes a throttle channel that decompresses and expands the high-pressure side refrigerant, a valve body that adjusts the opening of the throttle channel, and a valve body operating mechanism (power element) that displaces the valve body. An outlet refrigerant flow path for supplying the refrigerant decompressed and expanded in the throttle flow path to the evaporator, the outlet refrigerant flow path is opened and closed by the valve body of the electromagnetic valve, and the valve body of the electromagnetic valve is closed In some cases, the valve body of the throttle channel is closed by a diaphragm operating mechanism that operates the valve body based on the refrigerant pressure between the valve body of the electromagnetic valve and the throttle channel.
Japanese Patent Application Laid-Open No. 11-182983

In the above-mentioned patent document, when the solenoid valve is closed, the space between the valve body of the solenoid valve and the valve body of the throttle passage of the expansion valve becomes a sealed space, and this sealed space is filled with the liquid refrigerant. In this case, there is a possibility that this sealed space may become abnormally high pressure as the temperature of the atmosphere rises, and in order to avoid this, a minute communication path that connects the upstream side of the solenoid valve and the upstream side of the expansion valve is provided. Is. However, since this minute communication path is for escaping a small amount of refrigerant, it is required to have a very small diameter, and its processing becomes extremely difficult.
Accordingly, an object of the present invention is to provide an electromagnetic valve-integrated expansion valve that allows a required small amount of refrigerant to escape while maintaining a minute communication path having a diameter that can be easily processed.

The expansion valve integrated with an electromagnetic valve according to the present invention includes, as basic means, a valve chamber into which a high-pressure side refrigerant is introduced , a throttle passage communicating with the valve chamber , and a refrigerant decompressed and expanded in the throttle passage. A valve body having an outlet refrigerant flow path for supplying to the valve body, a valve body arranged in the valve chamber for opening and closing the throttle flow path, a power element for displacing the valve body , the valve chamber and the outlet refrigerant flow path , a bypass passage of the refrigerant provided between the an electromagnetic valve for opening and closing the bypass passage, and a micro communication passage provided so as to communicate between the bypass passage and the valve chamber, the micro communication passage, A micro orifice provided on the bypass passage side, and a valve body insertion portion that is provided between the micro orifice and the valve chamber and inserts a check valve body having a diameter larger than that of the micro orifice, The refrigerant pressure in the valve chamber In a state higher than the refrigerant pressure in the passage, the check valve body seals the micro-orifice to block the flow of refrigerant from the valve chamber to the bypass passage, and the refrigerant pressure in the bypass passage is reduced to the valve. in higher than the refrigerant pressure in the chamber Ru allowed to flow into the refrigerant of the bypass passage and the check valve body opening the small orifice into the valve chamber.

Further, the check valve body has an uneven to form a passage extending axially between the inner wall and the outer wall surface of the check valve of the micro communication passage, also be a rectangular column or cylinder it can.
Furthermore, the check valve body may be formed of a soft material such as rubber. In this case, the check valve body may be a cylindrical body having a bag-like hollow portion that opens to the valve chamber side. is there.
It is also possible to urge the check valve body toward the minute orifice through a spring.
Further, a large-diameter portion that accommodates the check valve body is formed on the valve chamber side of the minute communication path, and the check valve is held by a stopper piece that is generated by crimping the end portion of the large-diameter portion. By doing so, the check valve body can be held without increasing the number of parts.
Furthermore, the effective length dimension of the micro communication path in which the stopper piece is formed can be larger than the length dimension of the check valve body.
Further, the check valve body is movable in the axial direction of the minute communication path and can be biased toward the minute orifice via a spring.
Furthermore, the check valve body can include a tapered portion that contacts the minute orifice and a rectangular column portion that is continuous with the tapered portion.

  According to the present invention, when the solenoid valve is closed, it is possible to appropriately achieve the escape of the minute amount of the refrigerant while keeping the minute communication path for allowing the refrigerant to escape from the valve chamber to the solenoid valve side by an appropriate small diameter. . Therefore, processing becomes easy, and generation of refrigerant flow noise can be effectively suppressed.

FIG. 1 is a sectional view showing an embodiment of an expansion valve integrated with a solenoid valve according to the present invention, and FIG. 2 is an enlarged view of a main part.
An expansion valve integrated with an electromagnetic valve denoted as a whole by reference numeral 1 has a substantially prismatic valve body 10. The lower part of the valve body 10 has an inlet refrigerant passage (not shown) to which high-pressure refrigerant from the compressor side of the refrigeration cycle is supplied, and the inlet refrigerant passage communicates with a valve chamber 12 formed inside the valve body 10. Is done. A ball-shaped valve element 30 is supported in the valve chamber 12 by a spring 34 via a support member 32.

A nut member 40 is screwed into the opening of the valve chamber 12 and sealed. By screwing the nut member 40, the spring 34 is preloaded and the valve body 30 is supported via the support member 32 with a predetermined spring force. A seal member is attached to the nut member 40 to seal the valve chamber 12.
The refrigerant in the valve chamber 12 is decompressed and expanded through the throttle passage 14 between the valve body 30 and the valve seat, and flows out to the outlet refrigerant passage. The refrigerant from the outlet refrigerant channel is sent to an evaporator (not shown).

The refrigerant returned from the evaporator passes through a passage 18 provided in the upper part of the valve body 10 and is returned to a compressor (not shown). The refrigerant temperature in the passage 18 is transmitted via a temperature sensing rod 70 to a power element 50 that is a diaphragm operating mechanism that serves as a valve operating mechanism that drives a valve attached to the upper portion of the valve body 10.
The power element 50 has a housing 52 that is attached to the valve body 10 with a screw portion 54. Furthermore, it has the diaphragm 60 inserted | pinched and welded by the housing 52, and the upper chamber 62a and the lower chamber 62b are divided by the diaphragm 60. FIG. A working fluid is sealed in the upper chamber 62a, and the plug body 64 is sealed.

The diaphragm 60 is supported by a temperature sensitive rod 70. The temperature sensing rod 70 has a passage 72 through which refrigerant is introduced at the center.
The displacement of the temperature sensing rod 70 is transmitted to the valve body 30 via the valve rod 80.

  Since the expansion valve 1 is configured as described above, the temperature sensing rod 70 is driven by the operating position of the diaphragm 60 set according to the pressure and temperature of the refrigerant that flows out of the evaporator and passes through the passage 18. Thus, the gap of the throttle channel 14 between the valve body 30 and the valve seat is adjusted.

  Therefore, when the heat load of the evaporator is large, the gap between the valve body 30 and the valve seat is large, a large amount of refrigerant is supplied to the evaporator, and conversely, when the heat load is small, the flow rate of the refrigerant is small.

A solenoid valve 100 is attached to the side surface of the valve body 10.
The electromagnetic valve 100 includes a casing 110 and an attachment member 160 connected to the casing 110, and the attachment member 160 is attached to a bottomed opening formed in the valve body 10 via a screw portion.

The solenoid valve 100 has a coil 120 in a casing 110 and is supplied with power via a cord 122. A cylinder 124 is disposed at the center of the casing 110, and the plunger 140 is slidably inserted therein. A suction element 130 is fixed to the outside of the cylinder 124 with screws 132. A spring 142 provided between the suction element 130 and the plunger 140 urges the plunger 140 in a direction away from the suction element 130.
A pilot valve body 150 is slidably disposed at the tip of the plunger 140. The pilot valve body 150 has a valve hole 152 at the center.

  In the solenoid valve 100 configured as described above, when the coil 120 of the solenoid valve 100 is energized, the plunger 140 is pulled back to the attractor 130 side by the magnetic force of the coil 120. When the distal end portion 144 of the plunger 140 is separated from the valve hole 152 of the pilot valve body 150, the valve hole 152 is opened, and the refrigerant in the back pressure chamber 20a passes through the valve hole 152 and is introduced into the passage 25 of the conduit 24. The difference is reduced. Thereby, the pilot valve body 150 is separated from the tip of the conduit 24, the electromagnetic valve 100 is opened, and the refrigerant in the back pressure chamber 20a flows to the outlet refrigerant flow path side.

  The refrigerant in the valve chamber 12 is charged into the back pressure chamber 20a of the bottomed hole 20 to which the electromagnetic valve 100 is attached through the throttle passage 14 between the valve body 30 and the valve seat and through the bypass passage 21.

  On the contrary, the power supply to the coil 120 is cut off, and the distal end portion 144 of the plunger 140 is seated in the valve hole 152 of the pilot valve body 150 by the spring force of the spring 142 and the valve hole 152 is closed. Then, the refrigerant is introduced into the back pressure chamber 20a through the bypass passage 21 through the throttle channel 14 between the valve body 30 and the valve seat. Therefore, the distal end portion 144 of the plunger 140 is seated on the valve hole 152 to close the valve hole 152, and the pilot valve body 150 is seated on the end surface of the conduit 24 to close the passage 25. Thereby, the solenoid valve 100 returns to the closed state.

  2 and 3 show details of the check valve body disposed in the minute communication passage 22 that communicates with the bypass passage 21 via the minute orifice 23.

The check valve body 200 is made into a prismatic shape using a soft material such as rubber. Then, insert this check valve body 200 in a cylindrical bore shape of micro communication passage 22, it is fixed by the caulking portion K _1. A stepped hole 22 ′ is formed in the opening on the valve chamber 12 side of the minute communication passage 22, and a machining allowance for the crimping portion K ₁ is prepared.

  The upper surface of the soft check valve body 200 has a surface area that closes the micro orifice 23. When the pressure of the refrigerant is applied from the valve chamber 12 side, the check valve body 200 has a check valve function that closes the micro orifice to stop the flow of the refrigerant.

As shown in FIG. 4, when the pressure P ₁ of the refrigerant of the bypass passage 21 side communicating with the solenoid valve becomes excessive, the check valve body 200 of the soft is compressed and deformed in the axial direction to form a gap G _1. Due to this deformation, the micro orifice 23 is opened, and the refrigerant on the bypass passage 21 side passes between the micro communication passage 22 and the prismatic check valve body 200 and escapes to the valve chamber 12 side to prevent problems.

  Thus, the check valve body has a columnar shape having an end face for opening and closing the micro-orifice 23, and is formed so as to expand and contract in the axial direction by the pressure acting on the end face. For example, in addition to a prismatic shape, it can be a polygonal column such as a hexagon or a cylinder having a flat surface in part, and a flow path extending in the axial direction is formed between the inner wall surface of the micro communication path 22.

FIG. 5 is a cross-sectional view showing still another embodiment of the expansion valve integrated with a solenoid valve of the present invention, and FIG. 6 is a cross-sectional view of the main part.
The solenoid valve-integrated expansion valve, generally denoted by reference numeral 1A, differs from the solenoid valve-integrated expansion valve described in FIGS. 1 and 2 in the configuration of the minute communication passage 22a, the minute orifice 23a, and the check valve body 300. However, the configuration of other members is the same. Therefore, the same reference numerals are assigned to similar members, and detailed description thereof is omitted.

FIG. 7 is an explanatory view showing the structure of the minute communication passage 22a and the minute orifice 23a and the configuration of the check valve body 300 provided in the minute communication passage 22a.
Micro communication passage 22a is a cylindrical bore having an inner diameter D _1, it communicates with the bypass passage 21 through the small orifice 23a. A conical surface 23b may be provided at the opening of the minute orifice 23a on the minute communication path 22a side.

The check valve body 300 disposed in the minute communication path 22a is formed of a cylindrical body having an outer diameter dimension D ₁ and a length dimension H ₂ . A rubber member or the like is appropriate as the material of the cylindrical body, but other soft polymer materials such as silicon resin may be used. The opening on the valve chamber 12 side of the minute communication passage 22a is formed in a large-diameter hole 22b. After inserting the check valve body 300 into the micro communication passage 22a, it is subjected to caulking K _1, to form a stopper S _1, to hold the check valve member 300. In the this embodiment, although four stopper S ₁ is provided, the shape and number of the stopper piece S ₁ is selected appropriately.
Effective length of the micro communication passage 22a after stopper S ₁ is formed is next to H _1, the dimension H ₁ is set to a larger size than the length of H ₂ check valve body 300.

FIG. 7 shows a state in which the refrigerant pressure on the valve chamber 12 side is higher than the refrigerant pressure on the bypass passage 21 side. The reverse valve body 300 is pressed toward the micro orifice 23a by the pressure P ₂ on the valve chamber 12 side. The valve closing position is such that the orifice 23a is closed. Since the reverse valve body 300 is made of a soft material such as a rubber material, it has flexibility and reliably closes the micro orifice 23a.

FIG. 8 shows a state in which the refrigerant pressure on the bypass passage 21 side is higher than the refrigerant pressure on the valve chamber 12 side.
The check valve body 300 away from the small orifice 23a moves within micro communication passage 22a, falls onto the stopper pieces _{S 1.} Since the outer diameter D ₂ of the check valve body 300 has a smaller dimension than the inner diameter D ₁ of the micro communication passage 22a, passes through the refrigerant therebetween gaps G ₁ toward the side into the valve chamber from the bypass passage 21 side moves To do. The refrigerant passes through the gap G ₂ between the four stopper pieces S ₁ and goes to the valve chamber 12.

In the present embodiment, the check valve body 300 is a cylindrical body made of a rubber material or a soft material and can be manufactured very easily. Also, the minute communication passage 22a, the minute orifice 23a, the conical surface 23b, the large diameter portion 22b, and the like can be processed into the valve chamber in one direction from the side. Further, since the caulking K ₁ also valve body 10 to form the stopper S ₁ is made of a soft metal such as aluminum alloy, it can be easily processed.

FIG. 9 is a cross-sectional view showing still another embodiment of the expansion valve integrated with a solenoid valve of the present invention, and FIG. 10 is a cross-sectional view of a main part.
The solenoid valve-integrated expansion valve shown as a whole by reference numeral 1B differs from the solenoid valve-integrated expansion valve described in FIGS. 1 and 2 in the configuration of the minute communication passage 22e, the minute orifice 23e, and the check valve body 400. However, the configuration of other members is the same. Therefore, the same reference numerals are assigned to similar members, and detailed description thereof is omitted.

FIG. 10 is an explanatory diagram showing the structure of the minute communication passage 22e and the minute orifice 23e and the configuration of the check valve body 400 provided in the minute communication passage 22e.
The minute communication passage 22e is a cylindrical hole and communicates with the bypass passage 21 through the minute orifice 23e.
In this embodiment, the micro orifice 23e communicating with the bypass passage 21 opens on the side wall of the cylindrical hole-shaped micro communication passage 22e. A conical surface 23f may be provided at the connecting portion between the bypass passage 21 and the minute orifice 23e.

The check valve body 400 disposed in the minute communication path 22e is a cylindrical body having an outer diameter corresponding to the inner diameter of the minute communication path 22e. The cylindrical member is suitably a rubber member or the like, but may be another soft polymer material such as a resin. The opening on the valve chamber 12 side of the minute communication passage 22e is formed in a large-diameter hole 22f. After inserting the check valve body 400 into the micro communication passage 22e, subjected to Pirukashime machining K _2, to form a stopper S _2, it holds the check valve body 400.
In the this embodiment, although two stopper S ₂ is provided, the shape and number of the stopper piece S ₂ is selected as appropriate.

10, in the refrigerant pressure P ₂ of the valve chamber 12 side to the high state with respect to the refrigerant pressure P ₁ of the bypass passage 21 side, check valve body 400 is subjected to compressive forces in the axial direction. Upon receiving this compressive force, the check valve body 400 expands in the radial direction, and its outer peripheral portion 400a is in close contact with the minute orifice 23e to seal the minute orifice 23e.
When the refrigerant pressure P ₁ of the bypass passage 21 side becomes higher than the pressure P ₂ of the valve chamber 12 side, the refrigerant of the small orifice 23e causes the outer peripheral portion 400a of the check valve member 400 is elastically deformed inward, the high-pressure refrigerant Escape to the valve chamber 12 side.

FIG. 11 shows a modified example of the check valve body applied to the solenoid valve-integrated expansion valve described in the embodiment of FIGS.
The check valve body 500 is made of a soft material such as rubber or resin, and a bag-like hollow portion 510 having a cylindrical shape opens to the valve chamber 12 side. Since the check valve body 500 has a hollow portion, it receives pressure from the valve chamber side and easily expands in the radial direction to seal the minute orifice 23e. Further, since the elasticity in the radial direction is improved, it can be easily deformed by the refrigerant pressure on the micro orifice 23e side, and the high pressure can be released to the valve chamber side.

FIG. 12 is a sectional view showing still another embodiment of the expansion valve integrated with a solenoid valve according to the present invention, and FIG. 13 is an enlarged view of a main part.
The solenoid valve-integrated expansion valve shown as a whole by reference numeral 1C is different from the solenoid valve-integrated expansion valve described in FIGS. It is. Therefore, the same reference numerals are assigned to similar members, and detailed description thereof is omitted.

FIGS. 13 and 14 show details of the check valve body provided in the minute communication passage 22 that communicates with the bypass passage 21 through the minute orifice 23.
The check valve body 700 is made of resin, for example, and has a cylindrical body and a tapered portion 702 at the tip. The check valve body 700 opens and closes the micro-orifice 23 at the tapered portion 702 and functions as a check valve. A cut-off flat surface 704 is formed on the peripheral surface of the taper portion 702 to form a refrigerant passage space.

A support plate 720 is inserted on the valve chamber 12 side of the valve body 10 and is fixed by a crimping portion K ₁ formed in the opening of the chamber 22. The support plate 720 has a hole 722 in the center and allows the refrigerant to pass therethrough. A spring 710 is provided between the support plate 720 and the chamber 22.

When the pressure of the refrigerant passage 21 communicating with the solenoid valve is higher than the refrigerant pressure on the valve chamber 12 side when the solenoid valve of the solenoid valve-integrated expansion valve is closed, the check valve body 700 is minute. The pressure difference is eliminated away from the orifice 23. After the pressure difference is eliminated, the check valve body 700 is closed and functions as a normal expansion valve that does not have a minute communication path. In the case of this embodiment structure, the check valve body 700 may be a hard material.
With the above configuration, when there is a large pressure difference, the micro orifice 23 of the micro communication path 22 is closed by the check valve body 700, so that excessive refrigerant leakage from the micro communication path 22 can be prevented. Energy loss can be prevented.

FIG. 15 is an explanatory view showing another embodiment of the check valve body of the present invention.
The check valve body 800 includes a prismatic main body having four flat surfaces 804 and a tapered cone-shaped tapered surface 802 formed on the upper portion of the main body. The tapered surface 802 constitutes a check valve mechanism between the micro orifices 23. A semicircular groove 806 is provided at the bottom of the check valve body 800.

The check valve body 800 is inserted into the micro communication passage 22, falling off is prevented by the caulking portion K _1. The check valve body 800 is a resin-made small and lightweight member.
Therefore, in the state where the refrigerant pressure in the valve chamber 12 is higher than the pressure on the passage 21 side, the check valve body 800 is pressed by the minute orifice 23 to prevent the refrigerant from passing therethrough.
In a state where the pressure on the bypass passage 21 side is high, the micro orifice 23 is opened and the refrigerant flows to the valve chamber 12 side.

  In the solenoid valve-integrated expansion valve of the present invention, when the solenoid valve is operating (closed), the amount of refrigerant leaking from the minute communication path even when the refrigerant pressure on the valve chamber 12 side becomes high Can be minimized and energy loss can be prevented.

Sectional drawing which shows one Embodiment of the solenoid valve integrated expansion valve of this invention. Sectional drawing of the principal part. Explanatory drawing of the attachment structure of the non-return valve body of this invention. Explanatory drawing which shows the effect | action of this invention. Sectional drawing which shows other embodiment of this invention. Sectional drawing of the principal part of FIG. Explanatory drawing of a non-return valve body. Check valve body explanatory drawing. Sectional drawing which shows other embodiment of this invention. Sectional drawing of the principal part of FIG. Explanatory drawing which shows the modification of the non-return valve body applied to the solenoid valve integrated expansion valve demonstrated by embodiment of FIG. 9, FIG. Sectional drawing which shows other embodiment of the solenoid valve integrated expansion valve of this invention. Sectional drawing of the principal part of FIG. Explanatory drawing of a check valve structure. Explanatory drawing which shows other embodiment of a non-return valve body.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Expansion valve 10 Valve body 12 Valve chamber 14 Restriction flow path 16 Outlet refrigerant flow path 20 Bottomed hole 20a Back pressure chamber 21 Bypass path 22 Micro communication path 23 Micro orifice 24 Pipe 30 Valve body 50 Power element 60 Diaphragm 70 Temperature sensing rod 80 Valve Rod 100 Solenoid Valve 120 Coil 130 Suction Element 140 Plunger 150 Pilot Valve Body 200 Check Valve Body

Claims (9)

A valve body having a valve chamber into which the high-pressure side refrigerant is introduced , a throttle channel communicating with the valve chamber , an outlet refrigerant channel for supplying the refrigerant decompressed and expanded in the throttle channel to the evaporator, and the valve chamber a valve body disposed to open and close the throttle channel, to open and close a power element for displacing the valve body, the bypass passage of the refrigerant is provided between said valve chamber said outlet refrigerant flow path, the bypass path wherein an electromagnetic valve, a micro communication passage provided so as to communicate between the bypass passage and the valve chamber, the micro communication passage, and the minute orifice provided in the bypass passage side, a fine small orifice A valve body insertion portion that is provided between the valve chamber and inserts a check valve body having a diameter larger than that of the minute orifice, and the refrigerant pressure in the valve chamber is higher than the refrigerant pressure in the bypass passage Then, the check valve body is The fine orifice is sealed to block the flow of the refrigerant from the valve chamber to the bypass passage, and the check valve body is in the state where the refrigerant pressure in the bypass passage is higher than the refrigerant pressure in the valve chamber. solenoid valve integral expansion valve, wherein isosamples opening the small orifice to flow into the refrigerant in the bypass passage to the valve chamber. The check valve body, the solenoid valve according to claim 1, characterized in that it has an uneven to form a passage extending axially between the inner wall and the outer wall surface of the check valve body of the micro communication passage Integrated expansion valve. The check valve body, the solenoid valve integral expansion valve according to claim 1, characterized in that the prismatic body, or cylinder.   The solenoid valve-integrated expansion valve according to any one of claims 1 to 3, wherein the check valve body is formed of a soft material such as rubber. The solenoid valve-integrated expansion valve according to claim 4, wherein the check valve body is a cylindrical body having a bag-shaped hollow portion that opens to the valve chamber side. Wherein the valve chamber side of the opening of the micro communication passage is formed in the large diameter portion, the large diameter portion to the crimping process the check valve by a stopper piece formed by body held in the micro communication passage Item 6. The solenoid valve-integrated expansion valve according to any one of Items 1 to 5.   The solenoid valve-integrated expansion valve according to claim 6, wherein an effective length dimension of the minute communication path in which the stopper piece is formed is larger than a length dimension of the check valve body. The solenoid valve-integrated expansion valve according to claim 1, wherein the check valve body is movable in the axial direction of the minute communication path and is biased toward the minute orifice via a spring.   The solenoid valve-integrated expansion valve according to claim 8, wherein the check valve body includes a tapered portion that abuts on the minute orifice and a rectangular column portion that is continuous with the tapered portion.

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