JP2013122356A - Expansion valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an expansion valve capable of reducing force required to open/close an inflow port of a small diameter flow path without cost increase.SOLUTION: An expansion valve 40 adiabatically expands a flow-in refrigerant by making a refrigerant inlet 42a communicate with a refrigerant outlet 42 at a predetermined time period, by applying magnetic force to a valve body 44 at a predetermined duty ratio. The valve body 44 is formed in a rod shape, assumes a standby attitude in a regular state to allow a front end 441 to close an inflow hole port 431a of a small diameter part 431, thus restricting communication between a refrigerant inlet 42a and a refrigerant outlet 42b, and meanwhile assumes a drive attitude if magnetic force acts to itself to allow the front end 441 to open the inflow port 431a of the small diameter flow path 431, thus permitting communication between the refrigerant inlet 42a and the refrigerant outlet 42b through the small diameter flow path 431.

Description

  The present invention relates to an expansion valve, and more particularly to an expansion valve constituting a refrigeration cycle of a vending machine or the like.

  2. Description of the Related Art Conventionally, as an expansion valve constituting a refrigeration cycle, there has been known one in which a refrigerant is adiabatically expanded by opening and closing a solenoid valve at a specific time period (see, for example, Patent Document 1).

  FIG. 6 is a cross-sectional side view showing the configuration of this type of conventional expansion valve. As shown in FIG. 6, the expansion valve 100 forms a refrigerant circuit that constitutes a refrigerant cycle together with a compressor, a condenser, and an evaporator (not shown), and includes a valve body 110, a valve seat 120, and a plunger 130. And is configured.

  The valve body 110 constitutes a refrigerant inlet 110a, and constitutes an inlet port 111 connected to a high-pressure inlet pipe 251 through which a high-pressure refrigerant supplied from a condenser passes, and a refrigerant outlet 110b, and toward the evaporator. And an outlet port 112 connected to a low-pressure outflow pipe through which low-pressure refrigerant to be sent passes.

  The valve seat 120 is provided inside the valve body 110, and has a small-diameter channel 121 having a smaller diameter than the refrigerant inlet 110a and communicating with the refrigerant outlet 110b.

  Plunger 130 is provided inside valve body 110 so as to be capable of moving forward and backward in a manner of approaching and moving away from valve seat 120. The plunger 130 is connected to a lower end portion of a yoke 140 provided in a state where a part thereof is accommodated in the valve body 110 via a compression coil spring 150. In a normal state, the plunger 130 is urged by the compression coil spring 150 and is connected to the valve. By moving forward in a manner close to the seat 120, the lower end of the valve seat 120 serves as a valve body to close the inflow port 121a of the small-diameter channel 121 of the valve seat 120 (see the two-dot chain line in FIG. 6). . On the other hand, when a magnetic force acts on itself by a magnetic circuit formed by the yoke 140 and the electromagnetic coil 160 provided outside the valve body 110, the plunger 130 resists the urging force of the compression coil spring 150. Then, the inlet 121a of the small-diameter channel 121 is opened by moving backward in a manner away from the valve seat 120.

  In the conventional expansion valve 100 shown in FIG. 6, when the energization to the electromagnetic coil 160 is turned off, the plunger 130 is urged by the compression coil spring 150 to move forward, so that the small-diameter channel 121 is moved. When energization to the electromagnetic coil 160 is turned on while the inflow port 121a is closed, the plunger 130 moves backward against the urging force of the compression coil spring 150, so that the inflow port 121a of the small-diameter channel 121 is moved. It will be established.

  Then, the energization of the electromagnetic coil 160 is turned on / off at a predetermined duty ratio, and the inlet 121a of the small-diameter channel 121 is opened and closed by the valve body by the forward / backward movement of the plunger 130, whereby the refrigerant flowing in through the refrigerant inlet 110a It is adiabatically expanded in the passage 121 and flows out through the refrigerant outlet 110b.

Japanese Patent Laid-Open No. 53-1352

  Incidentally, in the conventional expansion valve 100 as described above, since the inlet 121a of the small-diameter channel 121 is opened and closed by the valve body by the forward and backward movement of the plunger 130, the refrigerant flowing in from the refrigerant inlet 110a (high-pressure refrigerant). When the pressure difference between the refrigerant and the refrigerant flowing out from the refrigerant outlet 110b (low pressure refrigerant) is large, the pressure difference applied to the valve body in the plunger 130 is also large, and the plunger 130 for opening the inlet 121a of the small-diameter channel 121 is opened. The power required for retreating will be excessive. Thus, if the force required for the backward movement of the plunger 130 becomes excessive, the electromagnetic coil 160 as an actuator is increased in size, resulting in an increase in cost, which is not preferable. Further, in order to reduce the force required for the backward movement of the plunger 130, it is conceivable to reduce the diameter of the small-diameter channel 121. However, in this case, dust or the like circulating in the refrigerant circuit together with the refrigerant may be clogged in the small-diameter channel 121. Therefore, there is a limit to reducing the diameter of the small-diameter channel 121.

  In view of the above circumstances, an object of the present invention is to provide an expansion valve that can reduce the force required to open and close the inlet of a small-diameter channel without increasing the cost.

  In order to achieve the above object, an expansion valve according to a first aspect of the present invention includes a valve body provided with a refrigerant inlet and a refrigerant outlet, a valve body provided inside the valve body, and having a smaller diameter than the refrigerant inlet. A valve seat having a small-diameter channel communicating with the refrigerant outlet, and provided inside the valve body, wherein the refrigerant inlet and the refrigerant outlet normally communicate with each other through the small-diameter channel. A valve body that allows the refrigerant inlet and the refrigerant outlet to communicate with each other through the small-diameter flow path when a magnetic force acts on the valve body, and controls the valve body at a predetermined duty ratio. The expansion valve that causes the refrigerant inlet and the refrigerant outlet to communicate with each other at a predetermined time period, adiabatically expands the refrigerant flowing through the refrigerant inlet through the small-diameter channel, and flows out through the refrigerant outlet. The valve body has a central portion supported by the valve body via a pin so that a distal end portion approaches and separates from the valve seat and a proximal end portion is close to a yoke provided in the valve body. It is in the form of a rod arranged so as to be swingable around the central axis of the pin in a separated manner. In a normal state, the distal end portion is close to the valve seat and the proximal end portion is separated from the yoke. The leading end closes the inlet of the small-diameter flow path in a separated standby posture, thereby restricting the refrigerant inlet and the refrigerant outlet from communicating with each other through the small-diameter flow path. In the case of action, the base end portion is close to the yoke and the distal end portion is separated from the valve seat so that the distal end portion opens the inlet of the small-diameter flow path, thereby The refrigerant outlet through the small-diameter channel Characterized in that it allows the communicating.

  The expansion valve according to a second aspect of the present invention is the expansion valve according to the first aspect described above, wherein the valve body has a distance from the central portion to the base end portion larger than a distance from the central portion to the distal end portion. And

  The expansion valve according to claim 3 of the present invention is the above-described expansion valve according to claim 1 or 2, wherein the expansion valve is provided in the valve body and communicates with the refrigerant inlet via a hole formed in the bottom. And a convex portion that is provided at a tip portion of the valve body and forms a narrow channel between the concave portion and the refrigerant inlet when the valve body is in a driving posture. Features.

  According to the present invention, the valve body is supported by the valve body through the pin, so that the distal end portion is moved closer to and away from the valve seat and the proximal end portion is closer to the yoke provided on the valve body. It is arranged so as to be able to swing around the central axis of the pin in a state of separating, and in a normal state, the coolant enters the standby position, and the tip portion closes the inlet of the small-diameter flow path, so that the refrigerant inlet and the refrigerant outlet When the magnetic force acts on itself, the refrigerant inlet and the refrigerant outlet are connected to each other through the small diameter channel by opening the small diameter channel inlet. Since it is allowed to communicate, the valve body operates on the “leverage principle” with the pin as a fulcrum. As a result, even if the pressure difference between the front and rear of the valve body is large due to the large pressure difference between the high-pressure refrigerant flowing from the refrigerant inlet and the low-pressure refrigerant flowing out from the refrigerant outlet, the force required to move the valve body can be reduced. it can. Therefore, the force required to move the valve body can be reduced in this way without causing an increase in the size of the actuator, etc., so that the force required to open and close the inlet of the small-diameter channel can be reduced without increasing the cost. There is an effect that it can be realized.

FIG. 1 is an explanatory diagram showing a case where an internal structure of a vending machine to which a refrigerant cycle apparatus having an expansion valve according to an embodiment of the present invention is applied is viewed from the front. FIG. 2 shows the internal structure of the vending machine shown in FIG. 1, and is a cross-sectional side view of the right commodity storage. FIG. 3 is a conceptual diagram conceptually showing a refrigerant cycle device applied to the vending machine shown in FIGS. 1 and 2. FIG. 4 is a cross-sectional side view showing a configuration of the expansion valve shown in FIGS. 2 and 3 and showing a state in which energization is turned off. FIG. 5 is a sectional side view showing a configuration of the expansion valve shown in FIGS. 2 and 3 and showing a state where energization is turned on. FIG. 6 is a cross-sectional side view showing a configuration of a conventional expansion valve.

  Hereinafter, preferred embodiments of an expansion valve according to the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is an explanatory diagram showing a case where an internal structure of a vending machine to which a refrigerant cycle apparatus having an expansion valve according to an embodiment of the present invention is applied is viewed from the front. The vending machine illustrated here includes a main body cabinet 1.

  The main body cabinet 1 has a rectangular shape with an open front surface. The main body cabinet 1 is provided with three independent commodity containers 3 partitioned by, for example, two heat insulating partition plates 2 in a side-by-side manner. This product storage 3 is for storing products such as canned beverages and beverages containing plastic bottles while maintaining a desired temperature, and has a heat insulating structure.

  FIG. 2 shows the internal structure of the vending machine shown in FIG. 1 and is a cross-sectional side view of the right product storage case 3. Here, the internal structure of the right product storage (hereinafter also referred to as right storage) 3a is shown, but the central product storage (hereinafter also referred to as intermediate storage) 3b and the left product storage (hereinafter referred to as right storage) 3a. The internal structure of 3c is also substantially the same as that of the right warehouse 3a. In the present specification, the right side indicates the right side when the vending machine is viewed from the front, and the left side indicates the left side when the vending machine is viewed from the front.

  As shown in FIG. 2, an outer door 4 and an inner door 5 are provided on the front surface of the main body cabinet 1. The outer door 4 is for opening and closing the front opening of the main body cabinet 1, and the inner door 5 is for opening and closing the front surface of the commodity storage 3. The inner door 5 is divided into upper and lower parts, and the upper door 5a opens and closes when a product is replenished.

  The product storage 3 is provided with a product storage rack 6, a payout mechanism 7 and a carry-out shooter 8. The commodity storage rack 6 is for storing commodities in a manner arranged in the vertical direction. The payout mechanism 7 is provided at the lower part of the product storage rack 6 and is used to carry out the products at the lowest level of the product group stored in the product storage rack 6 one by one. The carry-out shooter 8 is for guiding the product delivered from the delivery mechanism 7 to the product outlet 4 a provided in the outer door 4.

  FIG. 3 is a conceptual diagram conceptually showing a refrigerant cycle device applied to the vending machine shown in FIGS. 1 and 2. The refrigerant cycle device shown in FIG. 3 has a refrigerant circuit 10 in which a refrigerant (for example, carbon dioxide) is sealed. The refrigerant circuit 10 includes a main path 20, a high-pressure refrigerant introduction pipe 30, and a return pipe 32. It is configured with.

  The main path 20 is configured by sequentially connecting a compressor 21, an external heat exchanger 22, an auxiliary external heat exchanger 23, and an internal heat exchanger 24 through a refrigerant pipe 25.

  The compressor 21 is disposed in the machine room 9 as shown in FIG. The machine room 9 is a room inside the main body cabinet 1, partitioned from the product storage 3 and below the product storage 3. The compressor 21 sucks the refrigerant through the suction port, compresses the sucked refrigerant to be in a high-temperature and high-pressure state (high-pressure refrigerant), and discharges it from the discharge port.

  The compressor 21 according to the present embodiment is a two-stage compressor 21 that performs a compression operation in two steps. More specifically, the compressor 21 includes a first compression element 211 that performs a first compression operation and a second compression element 212 that performs a second compression operation, and an intermediate portion (not shown) therebetween. A heat exchanger is provided. The intermediate heat exchanger radiates the refrigerant compressed by the first compression operation by the first compression element 211 and sends it to the second compression element 212.

  The external heat exchanger 22 is disposed in the machine room 9 similarly to the compressor 21. When the refrigerant compressed by the compressor 21 passes through its flow path, the external heat exchanger 22 exchanges heat with ambient air to dissipate heat. A three-way valve 26 is provided in the refrigerant pipe 25 that connects the external heat exchanger 22 and the compressor 21. The three-way valve 26 will be described later.

  The auxiliary external heat exchanger 23 is configured integrally with the external heat exchanger 22 in a state where the fin member that is thermally connected to its flow path is shared with the external heat exchanger 22. Yes. The auxiliary external heat exchanger 23 heats the refrigerant passing through the flow path, that is, the refrigerant dissipated by the external heat exchanger 22 by heat exchange with ambient air.

  A plurality (three in the illustrated example) of the internal heat exchangers 24 are provided, and each of the internal heat exchangers 24 is disposed on the front side of the rear duct D in the low internal region of each commodity storage 3. The refrigerant pipe 25 connecting the internal heat exchanger 24 and the auxiliary external heat exchanger 23 is branched into three by a distributor 27 disposed in the middle thereof, and is disposed in the right warehouse 3a. To the internal heat exchanger (hereinafter also referred to as the right internal heat exchanger) 24a, the internal heat exchanger (hereinafter also referred to as the internal internal heat exchanger) 24b disposed in the central warehouse 3b, and the left warehouse 3c It is connected to the inlet side of the arranged internal heat exchanger (hereinafter also referred to as a left internal heat exchanger) 24c.

  In the refrigerant pipe 25, expansion valves 40a, 40b, and 40c (hereinafter collectively referred to as expansion valve 40) are provided on the way from the distributor 27 to the internal heat exchangers 24. The expansion valve 40 has a variable flow rate that can adjust the opening degree according to a command given from a controller (not shown), and can be in a fully closed state. The expansion valve 40 depressurizes the refrigerant passing therethrough and adiabatically expands, and the configuration thereof will be described later.

  The refrigerant pipes 25 connected to the respective outlet sides of the internal heat exchanger 24 are connected to the compressor 21 in such a manner that the refrigerant pipes 25 join at the first first junction P1 and communicate with the suction port of the compressor 21. It is.

  In such a main path 20, reference numerals 28 and 29 in FIG. 3 are a heater and an internal heat exchanger, respectively. The heater 28 is a heating means that is disposed in the inner box 3b and heats the internal air of the inner box 3b when driven and energized. The internal heat exchanger 29 exchanges heat between the high-pressure refrigerant that has passed through the auxiliary external heat exchanger 23 and the refrigerant (low-pressure refrigerant) that has passed through the internal heat exchanger 24.

  One end of the high-pressure refrigerant introduction pipe 30 is connected to the three-way valve 26, and the other end is connected to the inlet side of the heat exchanger 31 for heating provided in the left warehouse 3c. The high-pressure refrigerant introduction pipe 30 is for introducing the high-pressure refrigerant compressed by the compressor 21 into the heat exchanger 31 for heating.

  Here, the three-way valve 26 is selected between a first delivery state in which the high-pressure refrigerant compressed by the compressor 21 is delivered to the external heat exchanger 22 and a second delivery state in which the high-pressure refrigerant is delivered to the heating heat exchanger 31. It is a valve means that can be switched as a single unit. The switching operation of the three-way valve 26 is performed according to a command given from the controller.

  The return pipe 32 has one end connected to the outlet side of the heating heat exchanger 31 and the other end connected to the refrigerant pipe 25 constituting the main path 20, that is, the external heat exchanger 22 and the auxiliary external heat exchanger 23. To the second junction P2 of the refrigerant pipe 25 between the two. The return pipe 32 is for returning the refrigerant that has passed through the heating heat exchanger 31 to the main path 20.

  In such a refrigerant cycle device, the internal temperature of each commodity container 3 is controlled to a desired temperature by controlling the rotational speed of the compressor 21, the opening of the expansion valve 40, or the delivery state of the three-way valve 26 through a controller. The product can be adjusted to the state, and the product stored in the product storage 3 can be cooled or heated as follows. Here, when performing the CCC operation (operation for cooling the internal air of all the product storage boxes 3) and the HCC operation (heating the internal air of the left warehouse 3c and cooling the internal air of the right warehouse 3a and the middle warehouse 3b) The case where the operation is performed will be described as a representative example.

  First, the case where the CCC operation is performed will be described. In this case, the controller causes the three-way valve 26 to be in the first delivery state and adjusts the opening degree of the expansion valve 40.

  Thus, the refrigerant compressed by the compressor 21 passes through the three-way valve 26 in the first delivery state and reaches the external heat exchanger 22. The refrigerant that has reached the external heat exchanger 22 performs heat exchange with ambient air (outside air) while passing through the external heat exchanger 22, and dissipates heat. The refrigerant radiated by the external heat exchanger 22 reaches the auxiliary external heat exchanger 23, and while passing through the auxiliary external heat exchanger 23, exchanges heat with ambient air to further dissipate heat. The refrigerant radiated by the auxiliary heat exchanger 23 reaches the expansion valve 40 through the internal heat exchanger 29, and is adiabatically expanded by the expansion valve 40. The right internal heat exchanger 24a, the internal heat exchanger 24b, and It is sent to the left warehouse heat exchanger 24c.

  The refrigerant (low-pressure refrigerant) sent to each internal heat exchanger 24 passes through a refrigerant flow path (not shown) and exchanges heat with ambient air (internal air) to cool the ambient air. The cooled air circulates in the interior by driving the internal blower fan F1 disposed in the vicinity of each internal heat exchanger 24, whereby the products stored in each product storage 3 are cooled by the circulating air. Is done. The refrigerant that has passed through each internal heat exchanger 24 joins at the first junction P1, and then is sucked into the compressor 21 through the internal heat exchanger 29, is compressed by the compressor 21, and repeats the circulation described above.

  Next, a case where the HCC operation is performed will be described. In this case, the controller causes the three-way valve 26 to be in the second delivery state, causes the expansion valve 40c to be fully closed, and adjusts the openings of the expansion valves 40a and 40b.

  Thus, the refrigerant compressed by the compressor 21 passes through the three-way valve 26 that is in the second delivery state, and is sent to the heating heat exchanger 31 through the high-pressure refrigerant introduction pipe 30.

  The refrigerant (high-pressure refrigerant) sent to the heat exchanger 31 for heating passes through a refrigerant channel (not shown) and exchanges heat with ambient air (internal air) to heat the ambient air. The heated air circulates in the interior by driving the internal blower fan F <b> 1, whereby the products stored in each product storage 3 are heated by the circulating air.

  The refrigerant that has passed through the heating heat exchanger 31 reaches the second junction P2 after passing through the return pipe 32, and enters the main path 20 at the second junction P2. The refrigerant that has entered the main path 20 passes through the auxiliary external heat exchanger 23 and the internal heat exchanger 29 and then reaches the expansion valves 40a and 40b. The refrigerant expands adiabatically by the expansion valves 40a and 40b, and performs heat exchange in the right compartment. It is sent to the container 24a and the internal heat exchanger 24b.

  The refrigerant sent to the right internal heat exchanger 24a and the internal internal heat exchanger 24b passes through the refrigerant flow path and exchanges heat with ambient air (internal air) to cool the ambient air. The cooled air circulates in the interior by driving the internal blower fan F1, whereby the products stored in the right warehouse 3a and the central warehouse 3b are cooled by the circulating air. The refrigerant that has passed through the right internal heat exchanger 24a and the internal internal heat exchanger 24b joins at the first junction P1, and then is sucked into the compressor 21 through the internal heat exchanger 29 and compressed by the compressor 21. The above-described circulation is repeated.

  The structure of the expansion valve 40 will be described with reference to FIGS. 4 and 5 show the configuration of the expansion valve 40 shown in FIGS. 2 and 3, respectively. FIG. 4 is a cross-sectional side view showing a state where the energization is turned off, and FIG. It is a cross-sectional side view which shows the state performed. The expansion valve 40 shown in FIGS. 4 and 5 includes a yoke 41, a case 42, a valve seat 43, and a valve body 44.

  The yoke 41 is fixed by a fixing screw to the lower surface of the outer yoke 47 that forms the housing in such a manner as to penetrate the hollow portion 461 of the bobbin 46 around which the electromagnetic coil 45 is wound. The upper end portion 411 of the yoke 41 projects upward from the upper end of the bobbin 46.

  The case 42 is a valve body having a box shape and is attached to the outer yoke 47. In the case 42, the upper end 411 of the yoke 41 passes through an opening 421 formed in the bottom, and the upper surface of the bottom and the upper end surface of the yoke 41 constitute the same plane. The case 42 has an inlet port 422 and an outlet port 423.

  The inlet port 422 is provided at the top of the case 42. The inlet port 422 is a part connected to the refrigerant pipe 25 (hereinafter also referred to as the high-pressure refrigerant pipe 25) connected to the distributor 27, and constitutes a refrigerant inlet 42a.

  The outlet port 423 is provided at the bottom of the case 42 and below the inlet port 422. The outlet port 423 is a part connected to a refrigerant pipe 25 (hereinafter also referred to as a low-pressure refrigerant pipe 25) connected to the inlet side of the internal heat exchanger 24, and constitutes a refrigerant outlet 42b.

  The valve seat 43 is a columnar member provided in a state of being placed on the bottom inside the case 42, and has a small-diameter channel 431 extending in the vertical direction. The small-diameter channel 431 is a channel having a smaller diameter than the refrigerant inlet 42 a, more specifically, the inner diameter of the high-pressure refrigerant pipe 25, and has openings on the upper surface and the lower surface of the valve seat 43. Here, the opening on the upper surface side of the valve seat 43 is the refrigerant inlet 431a, and the opening on the lower surface side is the refrigerant outlet 431b. Such a small-diameter channel 431 communicates with the refrigerant outlet 42b via the outlet 431b.

  The valve body 44 has a rod-like shape, the distal end portion 441 is located above the valve seat 43, the proximal end portion 442 is located above the upper end surface of the yoke 41, and the central portion 443 is pivotally supported by a pin 425 provided on a support piece 424 erected on the bottom of the case 42. The valve body 44 is provided so as to be swingable around the central axis of the pin 425. More specifically, the valve body 44 is configured such that the distal end portion 441 approaches and separates from the valve seat 43 and the proximal end portion 442 is disposed on the yoke 41. The upper end face is provided so as to be able to swing in a manner of approaching and separating. In such a valve body 44, the distance from the central portion 443 to the base end portion 442 is larger than the distance from the central portion 443 to the distal end portion 441.

  Further, a convex portion 444 having a conical shape, for example, protruding upward is provided at the distal end portion 441 of the valve body 44. The convex portion 444 enters a concave portion 4221 formed in the inlet port 422. The concave portion 4221 communicates with the refrigerant inlet 42a through a hole portion 4222 formed in the bottom portion, and the peripheral surface is formed in a tapered shape so that the cross section gradually expands downward.

  In the expansion valve 40 configured as described above, as shown in FIG. 4, when energization to the electromagnetic coil 45 is turned off, the valve body 44 has the tip 441 of the valve seat 43 by its own weight. It becomes the stand-by posture placed on the upper surface. Thus, when the valve body 44 is in the standby posture, the distal end portion 441 closes the inlet 431a of the small-diameter channel 431. Thereby, the communication state of the refrigerant inlet 42a and the refrigerant outlet 42b is cut off, the expansion valve 40 is fully closed, and the passage of the refrigerant is restricted.

  On the other hand, as shown in FIG. 5, when energization to the electromagnetic coil 45 is turned on by an energization device (not shown), a magnetic circuit formed by the electromagnetic coil 45, the outer yoke 47, the valve body 44, the yoke 41, and the like. Due to this, a magnetic force acts on the valve body 44, whereby the valve body 44 swings in a manner in which the proximal end portion 442 is close to the upper end surface of the yoke 41 and the distal end portion 441 is separated from the valve seat 43. It becomes. When the valve body 44 is in the driving posture in this manner, the distal end portion 441 opens the inlet 431a of the small-diameter channel 431 and becomes smaller in diameter than the refrigerant inlet 42a between the convex portion 444 and the concave portion 4221. A narrow channel 49 is formed, and the refrigerant inlet 42 a and the refrigerant outlet 42 b communicate with each other via the narrow channel 49 and the small diameter channel 431.

  Thus, the high-pressure refrigerant that has flowed into the case 42 from the high-pressure refrigerant pipe 25 through the refrigerant inlet 42a is reduced in pressure by passing through the narrow channel 49, and further reduced in pressure by passing through the small-diameter channel 431. Then, after passing through the small-diameter channel 431, the refrigerant flows out from the refrigerant outlet 42b to the low-pressure refrigerant pipe 25.

  In such an expansion valve 40, when energization of the electromagnetic coil 45 from the energization device is turned on / off at a predetermined time period, that is, when a magnetic force is applied to the valve body 44 at a predetermined duty ratio, the valve body 44 is in a standby posture. The inlet 431a of the small-diameter channel 431 is opened and closed by swinging between the position and the driving posture, and the amount of reduced pressure of the refrigerant that adiabatically expands by passing through itself can be well adjusted. The evaporation temperature can be adjusted to a predetermined temperature.

  As described above, according to the expansion valve 40 according to the present embodiment, the valve body 44 is supported by the case 42 via the pin 425 in the central portion 443 so that the distal end portion 441 approaches and separates from the valve seat 43. In addition, the base end portion 442 is disposed so as to be able to swing around the central axis of the pin 425 in a manner that the base end portion 442 approaches and separates from the yoke 41, and when the energization to the electromagnetic coil 45 is turned off, When the tip 441 closes the inlet 431a of the small-diameter channel 431, the refrigerant inlet 42a and the refrigerant outlet 42b are restricted from communicating through the small-diameter channel 431, while a magnetic force acts on itself. Since the refrigerant inlet 42a and the refrigerant outlet 42b are allowed to communicate with each other through the small-diameter channel 431 by opening the inlet 431a of the small-diameter channel 431 in the driving posture, the valve body 44 is It will operate in "the principle of leverage" the down 425 as a fulcrum. Thereby, even if the pressure difference between the high pressure refrigerant flowing in from the refrigerant inlet 42a and the low pressure refrigerant flowing out of the refrigerant outlet 42b is large and the pressure difference across the valve body 44 is large, the force required to move the valve body 44 is reduced. Can be reduced. Accordingly, the force required to move the valve body 44 can be reduced in this way without incurring an increase in the size of the electromagnetic coil 45, so that the opening / closing of the inlet 431a of the small-diameter channel 431 can be performed without increasing the cost. The force required for the reduction can be reduced.

  As described above, the expansion valve according to the present invention is useful for a refrigerant cycle device such as a vending machine.

40 expansion valve 41 yoke 42 case 42a refrigerant inlet 42b refrigerant outlet 422 inlet port 4221 recess 423 outlet port 424 support piece 425 pin 43 valve seat 431 small diameter channel 431a inlet 431b outlet 44 valve body 441 distal end 443 base end 443 Central part 444 Convex part 45 Electromagnetic coil 46 Bobbin 461 Hollow part 47 Outer yoke 49 Narrow flow path N Fixing screw

Claims (3)

A valve body provided with a refrigerant inlet and a refrigerant outlet;
A valve seat provided inside the valve main body and having a small-diameter flow path having a smaller diameter than the refrigerant inlet and communicating with the refrigerant outlet;
It is provided inside the valve main body, and normally restricts the refrigerant inlet and the refrigerant outlet from communicating with each other through the small-diameter flow path, whereas when the magnetic force acts on itself, the refrigerant inlet and the refrigerant outlet A valve body that allows the refrigerant outlet to communicate with the small-diameter flow path,
By applying a magnetic force to the valve body at a predetermined duty ratio, the refrigerant inlet and the refrigerant outlet are communicated with each other at a predetermined time period, and the refrigerant flowing through the refrigerant inlet is adiabatically expanded in the small diameter channel. In the expansion valve that flows out through the refrigerant outlet,
The central part of the valve body is supported by the valve body via a pin, so that the distal end part approaches and separates from the valve seat and the proximal end part approaches and separates from a yoke provided in the valve body. The rod-shaped configuration is arranged so as to be swingable around the central axis of the pin. In the normal state, the distal end portion is close to the valve seat and the proximal end portion is separated from the yoke. The tip portion closes the inlet of the small-diameter channel by entering a standby posture, thereby restricting the refrigerant inlet and the refrigerant outlet from communicating with each other through the small-diameter channel, while a magnetic force acts on itself. In this case, the refrigerant inlet and the refrigerant are driven by a driving posture in which the proximal end is close to the yoke and the distal end is separated from the valve seat, and the distal end opens the inlet of the small-diameter channel. The outlet communicates with the small-diameter channel. Expansion valve, characterized in that to allow the.   The expansion valve according to claim 1, wherein the valve body has a distance from a central portion to a base end portion larger than a distance from the central portion to a distal end portion. A recess provided in the valve body and communicating with the refrigerant inlet via a hole formed in the bottom;
And a convex portion that is provided at a distal end portion of the valve body and forms a narrow channel between the concave portion and the refrigerant inlet when the valve body is in a driving posture. The expansion valve according to claim 1 or 2.

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