JP4727400B2 - Expansion valve - Google Patents

Description

  The present invention relates to an expansion valve used for controlling the flow rate of refrigerant supplied to an evaporator of an air conditioner.

  Conventionally, in a refrigeration cycle used in an air conditioner or refrigeration apparatus such as a room air conditioner or a car air conditioner, the evaporator is based on the refrigerant pressure on the outlet side of the evaporator (evaporator) that changes according to the load. The flow rate to is controlled. In this type of expansion valve, flow control is achieved by setting a spring force that urges the valve body in the valve closing direction after the parts are assembled due to the variation in accuracy of the parts that make up the expansion valve. There are two types of expansion valves: an expansion valve that adjusts the position of the valve, and an expansion valve that maintains the expected accuracy when assembling the components by eliminating the variation in the accuracy of the components as much as possible without providing screws for adjusting the springs. Proposed.

  As the latter expansion valve, the present applicant has proposed Japanese Patent Application No. 2004-207257.

  The block-shaped valve body of this type of expansion valve has a bottomed hole with an upper end opening, and the functional parts of the expansion valve (operating rod, orifice, valve body, biasing spring, etc.) have a bottomed hole from the opening end side. To be assembled.

Orifice is integrated with the actuating bar and slidably guided guide member is held by press-fitting the inner wall surface of the bottomed holes, in order to press-fitting holding made reliable, the prior invention However, the structure which caulks a bottomed hole by the upper end part side of the guide member was employ | adopted.

  However, according to this structure, in addition to the guide member having a stepped shape, a caulking allowance is required, and the guide member has a large diameter, which becomes an obstacle in the design or assembly process, and the expansion valve Further slimming and cost reduction were difficult.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an expansion valve that can be easily and reliably positioned in a valve body and is excellent in assembling performance at low cost.

In order to solve the above-described problems, an expansion valve according to the present invention includes a first passage for introducing high-pressure refrigerant condensed by a condenser into a valve chamber, a second passage through which refrigerant from the valve chamber toward the evaporator passes, and a compressor from the evaporator. A block-shaped valve main body having a third passage through which the refrigerant toward the passage passes, an orifice for depressurizing the high-pressure refrigerant introduced into the valve chamber, a valve body disposed opposite to the orifice, and the valve body A spring that biases the orifice toward the orifice, an operating rod that moves the valve body in a direction away from the orifice, and a power element that drives the operating rod based on the temperature and pressure of the refrigerant on the evaporator outlet side And forming the valve chamber with a bottomed hole and forming a thin wall between the bottomed hole and the second passage, In the state in which the orifice is press-fitted into the bottomed hole, the convex portion formed by punching the wall portion from the outlet side of the second passage is engaged with the concave portion formed in the orifice. An orifice is fixed in the bottomed hole .

According to this expansion valve, an orifice, a valve body, and a spring are disposed in a bottomed hole formed in the valve body, and the power element opens and closes the valve body with respect to the orifice via the operating rod. The flow rate through the fluid passage formed in the orifice is controlled. The orifice is press-fitted and retained in the bottomed hole, and in order to reinforce the prevention of slipping , the orifice is formed in the recess formed in the orifice between the bottomed hole and the second passage. The thin wall portion is punched from the outlet side of the second passage to engage the convex portion formed on the valve body to fix the orifice in the bottomed hole . Since the orifice is reinforced in the bottomed hole by the engagement of the concave and convex portions, the prevention of slipping in the valve operating axis direction is reinforced, so positioning is ensured with the orifice assembled in the bottomed hole, and the valve body is used as the orifice. The spring force of the spring that is biased toward the spring is set to a desired magnitude.

  In this expansion valve, the concave portion may be a concave groove formed on the outer periphery of the orifice. Since the concave groove engages with the convex portion, the orifice is reinforced to prevent the orifice from coming off in any direction of the valve operation. Since the engaging concave groove is easily and inexpensively formed by cutting or the like, an increase in cost can be suppressed as much as possible. By engaging the groove formed on the outer periphery of the orifice with the convex portion, the positioning of the orifice is ensured in the bottomed hole.

  In this expansion valve, the concave portion may be a step portion formed on the outer periphery of the orifice. The step portion is formed to engage with the convex portion formed on the valve body side in a direction opposite to the direction of the force of the spring that biases the orifice. Since the engaging stepped portion is easily and inexpensively formed by cutting or the like, an increase in cost can be suppressed as much as possible. By engaging the step portion and the convex portion formed on the outer periphery of the orifice, the prevention of the orifice from coming off is reinforced in the bottomed hole, and the positioning is ensured.

  In the above-described expansion valve, the convex portion can be formed by punching a part of the wall that separates the passage through which the refrigerant passes and the bottomed hole. The wall that separates the passage through which the refrigerant passes and the valved bottom hole can be made thin enough to be easily machined. Can be easily formed. Moreover, when punching such a wall, the machining tool can be advanced to the machining location using a passage through which the refrigerant passes.

  In the expansion valve, a guide member for guiding the operation of the operating rod is disposed in the bottomed hole as an integral structure or a separate structure with the orifice. When the guide member is integrated with the orifice, the number of parts can be reduced and the number of assembly steps can be reduced.

In the expansion valve according to the present invention, as described above, the orifice, the valve body, and the spring are arranged in the bottomed hole formed in the valve body, and the power element moves the valve body to the orifice via the operating rod. By opening and closing, the flow rate through the fluid passage formed in the orifice is controlled. By punching the thin wall portion formed between the bottomed hole and the second passage from the outlet side of the second passage while the orifice is press-fitted and held in the bottomed hole, By engaging the convex portion formed in the main body with the concave portion formed in the orifice, it is possible to reinforce prevention of the orifice that is press-fitted into the bottomed hole and to ensure positioning in the valve operating axis direction. . When the orifice is assembled in the bottomed hole, the spring force of the spring that urges the valve body toward the orifice is set to an intended magnitude depending on the position of the orifice. Therefore, since the spring force that determines the control of the flow rate of the refrigerant passing therethrough is set, it is possible to provide an expansion valve capable of easily and reliably positioning the orifice in the valve body.

  Hereinafter, embodiments of an expansion valve according to the present invention will be described with reference to the accompanying drawings. 1 is a longitudinal sectional view of an embodiment of the expansion valve according to the present invention, FIG. 2 is a right side view of the expansion valve shown in FIG. 1, and FIG. 3 is a left side view of the expansion valve shown in FIG.

  The expansion valve 1 shown in FIG. 1 to FIG. 3 is a first one that sends the high-pressure refrigerant compressed by the compressor 4 sequentially connected by the pipe 11, condensed by the condenser 5, and further recovered by the receiver 6 to the evaporator 8. A passage 20 and a second passage 24 are formed in the lower portion of the valve body 2, and a third passage 26 is formed in the upper portion of the valve body 2 to which the low-pressure refrigerant evaporated from the evaporator (evaporator) 8 is sent to the compressor 4. Has been. A bottomed hole 36 for communicating these passages 20, 24 is formed between the first passage 20 and the second passage 24, and a ball-shaped valve is provided in the bottomed hole 36 for controlling the refrigerant flow rate. A valve including a body 30, a spring 34 for urging the valve body 30 in the closing direction, and an orifice 40 is disposed. Furthermore, in order to operate the valve body 30 in the valve opening direction away from the orifice 40 against the urging force of the spring 34, an operation rod 60 that penetrates the valve body 2 up and down and penetrates the orifice 40, and an operation rod 60 are provided. A power element 70 to be activated is provided. The valve body 30 biased in the direction of the orifice 40 by the spring 34 is opened and closed by the operation of the operating rod 60. The power element 70 operates the operating rod 60 according to the pressure of the working fluid on the output side of the evaporator 8, so that the expansion valve 1 is controlled to open and close according to the magnitude of the load.

  A space at the bottom of the bottomed hole 36 serves as a valve chamber 22 that houses a support member 32 that supports the valve body 30 and a spring 34, and is connected to the passage of the orifice 40. In the space above the bottomed hole 36, a guide member 35 for guiding the operating rod 60 is disposed. Specifically, the guide member 35 is press-fitted into the bottomed hole 36 to guide the vertical movement of the operating rod 60. ing. In this embodiment, the guide member 35 is configured as a separate part from the orifice 40. In the middle region of the bottomed hole 36 formed between the guide member 35 and the orifice 40, the entire width of the bottomed hole 36 is a passage 38 that connects the passage of the orifice 40 to the second passage 24.

  The bottomed hole 36 is not formed by penetrating the valve body 2. That is, the expansion valve 1 is a type in which the compression force of the spring can be adjusted by screwing a screw-adjustable plug into the through-hole, such as an expansion valve of a type in which a through-hole is formed in the valve body 2. is not.

  The orifice 40 has a groove 50 as a recess formed on the outer periphery. In this example, the concave groove 50 is formed in an annular groove. When the orifice 40 is pushed into the bottomed hole 36 and is press-fitted to a predetermined depth, a portion corresponding to the concave groove 50 in the wall 51 forming the bottomed hole 36 is punched to form a bottomed hole. The convex portion 52 that has been struck and deformed inside 36 enters the concave groove 50 and becomes caulked.

  Due to the engagement between the convex portion 52 and the concave portion 50, the orifice 40 is reinforced in the bottomed hole 36 in the vertical direction, that is, in any direction of the operating direction of the operating rod 60. The positioning of the is ensured. Although the pressure of the refrigerant flowing in the first passage 20 and the second passage 24 is high, even if such pressure acts on the orifice 40, it is possible to prevent the orifice 40 from coming out from the bottomed hole 36. The wall 51 is a wall that separates the second passage 24 and the bottomed hole 36, and can be formed thin enough to be punched by design. The punching can be performed using the second passage 24. That is, the wall 51 can be processed by inserting a tool such as a punch from the opening side of the second passage 24.

  Since the expansion valve 1 is not formed with a hole that opens downward and is screwed, when assembling the expansion valve 1, the spring 34, the support member 32, and the valve body 30 are bottomed holes from the upper side in this order. It is configured to drop into 36. The machining accuracy of these parts is determined in advance so that the variation is within a predetermined range. By positioning the orifice 40 in the bottomed hole 36, the desired assembly accuracy including the load of the spring 34 is automatically obtained.

  FIG. 4 is a longitudinal sectional view showing another embodiment of the expansion valve according to the present invention. Since the side view is the same as FIGS. 2 and 3, the illustration is omitted. The expansion valve 1a shown in FIG. 4 is configured as an integral part 41 in which the orifice 40 and the guide member 35 are integrated. A portion corresponding to the passage 38 in the first embodiment is formed as a hole passage 44 formed through the integral part 41 in the radial direction. In this embodiment, it is necessary to pay attention to the orientation of the integral part 41 in the bottomed hole 36 so that the hole passage 44 is aligned with the second passage 24.

  FIG. 5 shows a partial view of another embodiment of the expansion valve according to the present invention. In this example, the concave portion is a concave portion formed by a stepped portion 55 formed on the outer periphery of the orifice 45. The engagement by the deformation of the wall portion of the bottomed hole 36 is the same as in the first embodiment. The convex part 52 struck by the punch engages with the step part 55. The step portion 55 has a structure in which the lower side of the orifice 45 becomes the large diameter portion 56 and the upper side becomes the small diameter portion 57, and the spring force in the direction in which the orifice 45 is urged through the valve body 30 (upward in the drawing). On the other hand, it is formed so that it can be countered by engagement with the convex portion 52.

  In the expansion valve according to the present invention, reliable positioning of the orifices 40 and 45 in the bottomed hole 36 is performed by a concave portion formed in the orifice, and a convex portion formed by simple wall surface deformation of the bottomed hole 36 such as punching. It can be easily obtained by engagement. Further, since the setting strength of the spring at the time of positioning the orifice can be obtained automatically and easily, the expansion valve can be manufactured at a lower cost.

It is a longitudinal cross-sectional view of one Example of the expansion valve by this invention. It is a right view of the expansion valve shown in FIG. It is a left view of the expansion valve shown in FIG. It is a longitudinal cross-sectional view which shows another Example of the expansion valve by this invention. It is a fragmentary figure which shows the other Example of the expansion valve by this invention.

Explanation of symbols

1, 1a Expansion valve 2 Valve body 4 Compressor 5 Condenser 6 Receiver 8 Evaporation 11 Pipe 20 First passage 24 Second passage 26 Third passage 30 Valve body 32 Support member 34 Spring 35 Guide member 36 Bottomed hole 38 Passage 40 Orifice 41 Integral part 44 Hole passage 45 Orifice 50 Concave part 51 Wall part 52 Convex part 55 Step part 56 Large diameter part 57 Small diameter part 60 Actuator 61 Lower end part 62 Shoulder part 70 Power element

Claims (5)

A block-shaped valve having a first passage for introducing high-pressure refrigerant condensed by a condenser into the valve chamber, a second passage through which the refrigerant from the valve chamber to the evaporator passes, and a third passage through which the refrigerant from the evaporator to the compressor passes. A main body, an orifice that depressurizes the high-pressure refrigerant introduced into the valve chamber, a valve body disposed opposite the orifice, a spring that biases the valve body toward the orifice, and the valve body An expansion valve comprising: an operating rod that moves the operating rod away from the orifice; and a power element that drives the operating rod based on the temperature and pressure of the refrigerant on the evaporator outlet side,
The valve chamber is formed by a bottomed hole and a thin wall portion is formed between the bottomed hole and the second passage, and the orifice is press-fitted into the bottomed hole. An expansion valve characterized in that a convex portion formed by punching the wall portion from an outlet side of a passage is engaged with a concave portion formed in the orifice to fix the orifice in the bottomed hole .   The expansion valve according to claim 1, wherein the concave portion is a concave groove formed on an outer periphery of the orifice.   The expansion valve according to claim 1, wherein the concave portion is a stepped portion formed on an outer periphery of the orifice. The expansion valve according to claim 1 , wherein a guide member for guiding the operating rod is provided in the bottomed hole . The expansion valve according to claim 4, wherein the guide member is formed integrally with the orifice .

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