JP2011133157A - Expansion valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce noise of an expansion valve for reducing a pressure of a refrigerant in a refrigerating cycle and controlling a flow rate of the refrigerant. <P>SOLUTION: A valve body 30 is provided with an inlet port 321 for introducing the refrigerant of high pressure condensed by a condenser, a valve chest 35 communicated with the inlet port, a valve hole 32a formed on the valve chest and an outlet port 331 for leading out the refrigerant expanded in the valve hole toward the external. One end 37c of an actuating bar 37 supported by the valve body slidably in the axial direction, is inserted to the valve hole, and kept into contact with a valve member 32b disposed in the valve chest. A valve member driving device 36 disposed at an upper end side of the valve body drives the valve member through the actuating bar to control an opening of the valve hole. As an inner diameter of the valve hole is determined to be 2.0-3.6 mm, and a diameter of one end of the actuating bar inserted to the valve hole is determined to be 0.6-1.4 mm, the resistance in allowing the refrigerant to pass through the valve hole is reduced, and noise can be reduced. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a temperature sensing mechanism built-in type expansion valve used in a refrigeration cycle.

  Conventionally, for a refrigeration cycle used in an air conditioner or the like mounted in an automobile, a temperature expansion valve with a built-in temperature sensing mechanism that adjusts the passage of refrigerant according to the temperature is used to omit installation space and wiring. ing.

  FIG. 3 is a cross-sectional view showing an example of a conventional temperature sensing mechanism built-in type expansion valve. The valve body 30 having a prismatic shape has a high pressure liquid refrigerant condensed by the condenser 5 and passed through the receiver 6. A first passage 32 serving as a passage and a second passage 34 through which the gas phase refrigerant supplied from the refrigerant outlet of the evaporator 8 to the refrigerant inlet of the compressor 4 flows are formed apart from each other in the vertical direction. . In addition, 11 is piping.

  The inlet passage 32 has an inlet port 321 for introducing liquid refrigerant, a valve chamber 35 communicating with the inlet port 321, a valve hole 32 a provided in the valve chamber 35, and refrigerant expanded in the valve hole 32 a. An outlet port 331 leading out is provided. A valve seat is formed at the inlet of the valve hole 32a, and a valve member 32b is disposed opposite to the valve seat. The valve member 32b is urged toward the valve seat by a compression coil spring 32c. . Reference numeral 32d denotes a support member that supports the valve member 32b. A vibration-proof spring 32 e that prevents vibration of the support member 32 d is fixed to the support member 32 d and is in sliding contact with the inner surface of the valve chamber 35. The lower end of the valve chamber 35 opens to the bottom surface of the valve body 30 and is sealed by a plug 38 screwed to the valve body 30.

  A valve member driving device 36 for driving the valve member 32 b is attached to the upper end of the valve body 30. The valve member driving device 36 has a pressure operating housing 36d in which the inner space is partitioned into two upper and lower pressure operating chambers 36b and 36c by a diaphragm 36a. The pressure actuating housing 36d communicates with the second passage 34 via a pressure equalizing hole 36e formed concentrically with the center line of the valve hole 32a.

  In the valve main body 30, an operating rod 37 extending from the lower surface side of the diaphragm 36a to the valve hole 32a is disposed. The operating rod 37 is slidably guided in a vertical direction by a sliding guide hole provided in a partition wall between the first passage 32 and the second passage 34 in the valve main body 30, and has a lower end at the valve member 32b. It is in contact. Note that a sealing member 36g for preventing the refrigerant from leaking between the first passage 32 and the second passage 34 is attached to the partition wall.

  The pressure working chamber 36b above the pressure working housing 36d is filled with a known diaphragm driving fluid, and the diaphragm driving fluid contains the working rod 37 and the pressure rod 37 located in the second passage 34 and the pressure equalizing hole 36e. Heat of the gas-phase refrigerant flowing through the second passage 34 is transmitted through the diaphragm 36a. The diaphragm driving fluid in the upper pressure working chamber 36b is gasified in response to the transmitted heat, and the gas pressure acts on the upper surface of the diaphragm 36a. The diaphragm 36a is displaced up and down in accordance with the difference between the pressure of the diaphragm driving fluid acting on the upper surface of the diaphragm 36a and the pressure applied to the lower surface of the diaphragm 36a. The vertical displacement of the central portion of the diaphragm 36a is transmitted to the valve member 32b via the receiving member 36h and the operating rod 37, and causes the valve member 32b to approach or separate from the valve seat of the valve hole 32a. As a result, the refrigerant flow rate toward the evaporator 8 is controlled. This type of expansion valve is disclosed, for example, in Patent Document 1 below.

JP 2004-138292 A

In this type of expansion valve, the inner diameter of the valve hole 32a is set according to the refrigerant flow rate required in the refrigeration cycle in which the expansion valve is incorporated, and is generally set between 2.0 and 3.6 mm. The Conventionally, there has been a problem that annoying noise is generated due to resistance generated between the operating rod 37 and the refrigerant passing through the valve hole 32a.
The objective of this invention is providing the expansion valve which eliminates the malfunction mentioned above.

  In order to achieve the above object, an expansion valve according to the present invention includes an inlet port for introducing a high-pressure refrigerant condensed by a condenser, a valve chamber communicating with the inlet port, a valve hole provided in the valve chamber, and the valve A valve body having an outlet port for leading the refrigerant expanded in the hole toward the outside, a valve member disposed in the valve chamber for opening and closing the valve hole, and supported by the valve body so as to be slidable in the axial direction. An expansion valve comprising: an operating rod having one end inserted into the valve hole; and a valve member driving device disposed on the other end side of the operating rod and driving the valve member via the operating rod. The inner diameter of the valve hole is set to 2.0 to 3.6 mm, and the diameter of one end of the operating rod is set to a range of 0.6 to 1.4 mm.

  According to the expansion valve of the present invention, since the resistance when the refrigerant passes through the valve hole is reduced, the refrigerant passing sound is reduced.

Front sectional view showing an embodiment of the present invention 1 is an enlarged view of the main part of FIG. Explanatory drawing of schematic structure of conventional expansion valve

  FIG. 1 is a front sectional view of an expansion valve according to an embodiment of the present invention, and FIG. 2 is an enlarged view of a main part of FIG. In the present embodiment, portions corresponding to those of the conventional example described above are denoted by the same reference numerals, and redundant description is omitted.

  In the present embodiment, the lower end of the actuating rod 37 is formed so as to reduce the diameter in two steps downward. The actuating rod 37 is made of SUS material, and as shown in FIG. 2, a base portion 37a having a diameter D1 extending from the upper end to the vicinity of the central axis of the outlet port 331, and a diameter D2 (D2 <D1) connected to the lower end. It has a first reduced diameter portion 37b and a second reduced diameter portion 37c having a diameter D3 (D3 <D2) connected to the lower end thereof and inserted into the valve hole 32a. In this embodiment, D1 = 2.4 mm, D2 = 1.6 mm, and D3 = 1.0 mm. The inner diameter d of the valve hole 32e is 3.1 mm.

  According to such a configuration, the width of the annular gap formed between the inner peripheral surface of the valve hole 32a and the outer peripheral surface of the second reduced diameter portion 37c of the operating rod 37 is the same as that of the conventional expansion valve (operating rod). The diameter of the portion inserted into the valve hole in the case is larger than 1.6 mm), and the resistance during passage of the refrigerant is reduced, so that noise is reduced.

  In addition, the diameter of parts other than this part can be enlarged by reducing the diameter (the 2nd diameter reducing part 37c) inserted in the valve hole 32a in the operating rod 37 like this embodiment. Therefore, the actuating rod 37 is less likely to buckle and the reliability is improved.

  Further, in this embodiment, the portions of the operating rod 37 where the diameter changes are tapered inclined surfaces 37d and 37e that are inclined with respect to the axis of the operating rod 37, and enter the outlet port 33 from the valve hole 32a. A part of the refrigerant flowing in is guided in a direction inclined with respect to the axis of the operating rod 37 along the inclined surfaces 37d and 37e. Since the outlet port 33 is formed in a direction orthogonal to the axis of the operating rod 37, the refrigerant flowing into the outlet port 33 from the valve hole 32a is less likely to collide with the wall surface of the outlet port 33, and noise is reduced.

  In addition, this invention is not limited to the said embodiment, A various change can be given to said embodiment in the range which does not deviate from the summary of this invention.

  For example, the inner diameter of the valve hole can be appropriately set within a range of 2.0 to 3.6 mm, and the diameter of the portion inserted into the valve hole of the operating rod can be set within a range of 0.6 to 1.4 mm.

  Further, in the above embodiment, the operating rod is reduced in diameter in two steps to form the tapered inclined surface at two locations in the axial direction, but such inclined surfaces may be formed at three or more locations, One place may be sufficient.

  In addition, various modifications can be made to the above-described embodiment without departing from the gist of the present invention.

30 Valve body 32 First passage 32a Valve hole 32b Valve member 321 Inlet port 331 Outlet port 34 Second passage 35 Valve chamber 36 Valve member driving device 37 Actuating rod 37a Base portion 37b First reduced diameter portion 37c Second reduced portion Diameter part 37d Inclined surface 37e Inclined surface

Claims (4)

  An inlet port for introducing a high-pressure refrigerant condensed by a condenser, a valve chamber communicating with the inlet port, a valve hole provided in the valve chamber, and an outlet port for leading the refrigerant expanded in the valve hole to the outside A valve body, a valve member disposed in the valve chamber, for opening and closing the valve hole, an operating rod that is supported by the valve body so as to be slidable in the axial direction, and one end of which is inserted into the valve hole; An expansion valve provided on the other end side of the rod and provided with a valve member driving device for driving the valve member via the operating rod, wherein the valve hole has an inner diameter of 2.0 to 3.6 mm, An expansion valve characterized in that the diameter of one end of the operating rod is set within a range of 0.6 to 1.4 mm.   The expansion valve according to claim 1, wherein one end of the operating rod has a reduced diameter.   The outlet port is formed in a direction orthogonal to the axis of the actuating rod, and a portion where the diameter of the actuating rod changes is located in the outlet port and is an inclined surface inclined with respect to the axis of the actuating rod. The expansion valve according to claim 2, wherein:   4. The expansion valve according to claim 3, wherein the operating rod is reduced in diameter in a multistage manner in the outlet port, and the inclined surfaces are formed at a plurality of locations in the axial direction of the operating rod.

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