JP2018159447A - Motor valve and refrigeration cycle system using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor valve which inhibits a brazing agent from reaching a seal part and enables a valve seat member to be easily press-fitted, and to provide a refrigeration cycle system using the motor valve.SOLUTION: A step part 7C is formed on an inner peripheral surface of a valve seat member 7 to cause a brazing agent to accumulate in the step part 7C and be inhibited from reaching a seal part 71 even if the brazing agent flows into an inner peripheral surface side of the valve seat member 7 when a joint pipe 23 is brazed to a cylindrical opening 22. Further, a thin part 7B is formed closer to a joint pipe 23 side than a thick part 7A in which the seal part 71 is formed to cause the thin part 7B to easily press-fit in the cylindrical opening.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an electric valve and a refrigeration cycle system using the same.

  In general, an electric valve may be used as an expansion valve in a refrigeration cycle system of an air conditioner such as a packaged air conditioner or a room air conditioner. In such an electric valve, the valve seat member is configured separately from the valve housing, and the joint pipe may be fixed to the valve housing by brazing. At this time, if the molten brazing material flows into the inner peripheral surface side of the valve seat member and reaches the seal portion (portion where the valve body is seated or separated) and solidifies, the port diameter decreases or the valve There was a possibility that the body could not sit normally, resulting in a decrease in flow rate and valve leakage.

  Therefore, as such an electric valve, a valve in which a groove is formed on the inner peripheral surface of a valve seat ring (valve seat member) press-fitted into a cylindrical portion (cylindrical opening) of the valve housing has been proposed ( For example, see Patent Document 1). In the motor-operated valve described in Patent Document 1, the brazing material that has flowed into the inner peripheral surface side of the valve seat ring is accumulated in the groove, so that it is difficult to reach the valve seat (seal portion).

JP 2013-164124 A

  However, in the electric valve described in Patent Document 1, the valve seat ring needs to have a predetermined thickness in order to form a groove, and it is difficult to press-fit into the tubular portion. When the valve seat ring is forcibly press-fitted, deformation and distortion of the press-fitted portion are transmitted to the seal portion, which may reduce the shut-off performance. Thus, it has been difficult to satisfy both the suppression of the brazing material reaching the seal portion and the ease of press-fitting the valve seat member.

  An object of the present invention is to provide an electric valve that can suppress the brazing material from reaching the seal portion and can easily press-fit a valve seat member, and a refrigeration cycle system using the electric valve. It is in.

  In the motor-operated valve of the present invention, a joint pipe is connected to a cylindrical opening of a valve housing, a valve seat member is press-fitted, and a valve body is seated on or separated from a seal portion of the valve seat member. An electric valve that opens and closes, wherein an inner diameter of the seal portion is smaller than an inner diameter of the joint pipe, and the valve seat member includes a thick portion where the seal portion is formed, and the joint than the thick portion. A thin-walled portion formed on the tube side and having an enlarged inner diameter, and a stepped portion formed on an inner peripheral surface between the thin-walled portion and the thick-walled portion.

  According to the present invention, since the step portion is formed on the inner peripheral surface of the valve seat member, the brazing material is connected to the inner periphery of the valve seat member when the joint pipe is brazed to the cylindrical opening. Even if it flows into the surface side, the brazing material accumulates in the step portion, and can reach the seal portion. Further, since the thin portion is formed closer to the joint pipe than the thick portion where the seal portion is formed, the thin portion can be easily press-fitted into the cylindrical opening. The valve seat member may be press-fitted into the entire thin wall portion and the thick wall portion may not be press-fitted, or the entire thin wall portion and a part of the thick wall portion may be press-fitted. Only a part may be press-fitted.

  At this time, in the electric valve according to the present invention, the thick portion is formed between an intermediate inner diameter portion having an inner diameter smaller than the thin portion and larger than the seal portion, and between the intermediate inner diameter portion and the seal portion. And a second step portion formed on the inner peripheral surface.

  According to such a configuration, since the intermediate inner diameter portion is formed in the thick portion, it is possible to suppress a sudden change in inner diameter between the seal portion and the thin portion, and the fluid passes through the valve seat member. When this occurs, turbulence is less likely to occur and noise can be suppressed. At this time, each of the stepped portion between the thick portion and the thin portion and the second stepped portion in the thick portion is a portion where brazing material is accumulated, and compared with the configuration having one step portion. Although the step height of the step portion is small, it is difficult to reduce the total amount of brazing material that can be accumulated.

  In the motor-operated valve of the present invention, it is preferable that the thin portion has an inner diameter such that the inner peripheral surface thereof is smoothly continuous with the inner peripheral surface of the joint pipe. According to such a configuration, turbulent flow is unlikely to occur between the valve seat member and the joint pipe when the fluid passes, and noise can be suppressed.

  In the motor-operated valve of the present invention, it is preferable that the thin portion is inclined so that at least the outer peripheral surface is reduced in diameter toward the joint pipe side. According to such a structure, it is easy to press-fit the thin portion into the cylindrical opening.

  The refrigeration cycle system of the present invention is a refrigeration cycle system including a compressor, a condenser, an expansion valve, and an evaporator, and the electric valve according to any one of the above is used as the expansion valve. It is characterized by being. According to the present invention, the motor-operated valve as described above is used, and the brazing material is suppressed from reaching the seal portion. Further, since the valve seat member can be easily press-fitted and deformation and strain are not easily transmitted to the seal portion, the shut-off property is improved. Accordingly, it is possible to suppress a decrease in operating efficiency of the refrigeration cycle system.

  According to the electric valve of the present invention, the valve seat member has the thin wall portion and the stepped portion, so that the brazing material can be prevented from reaching the seal portion, and the valve seat member can be easily press-fitted. it can.

It is sectional drawing which shows the motor operated valve which concerns on one Embodiment of this invention. It is sectional drawing which expands and shows the principal part of the said motor operated valve. It is a side view which shows the valve seat member of the said motor operated valve. It is sectional drawing which shows a mode that a joint pipe is brazed in the said motor operated valve. It is a schematic block diagram which shows the refrigerating cycle system in which the said motor operated valve is used.

  Hereinafter, each embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, a motor-operated valve 1 according to the present embodiment is used in a refrigeration cycle system for an air conditioner such as a packaged air conditioner or a room air conditioner, and includes a valve housing 2, a valve body 3, and a valve holder. 4, a support member 5, and a stepping motor 6. In the present embodiment, the operation direction of the valve body 3 is defined as a Z direction, and two directions substantially orthogonal to the Z direction are defined as an X direction and a Y direction, respectively.

  The valve housing 2 is formed in a cylindrical shape extending in the Z direction, and accommodates the valve body 3 and the valve holder 4 in the inner valve chamber 2A. In addition, a joint pipe 21 that communicates with the valve chamber 2 </ b> A and extends in the X direction is attached to the side surface of the valve housing 2, and a cylindrical opening 22 is formed at the lower end. An end of a joint pipe 23 extending in the Z direction is inserted and connected to the cylindrical opening 22, and the valve seat member 7 is press-fitted so as to be adjacent to the joint pipe 23. The joint pipe 23 communicates with the valve port 70 of the valve seat member 7.

  The valve body 3 is fixed to the lower end of the valve holder 4 and extends downward, and has a needle valve 31 at the tip. The needle valve 31 is seated or separated from a seal portion 71 (described later) of the valve seat member 7.

  The valve holder 4 is formed in a cylindrical shape extending along the Z direction, and an upper end portion thereof is engaged with a lower end portion of a rotor shaft 61 described later of the stepping motor 6. That is, the valve holder 4 is suspended by the rotor shaft 61 and is rotatable with respect to the rotor shaft 61. Further, a compression coil spring 41 is provided in the valve holder 4, and a downward load is applied to the valve body 3. For convenience of explanation, the compression coil spring 41 is omitted in FIG.

  The support member 5 is fixed to the valve housing 2 at the flange portion 51 so as to close the upper opening of the valve housing 2. The support member 5 accommodates the valve holder 4 and guides it in the Z direction, a female thread portion 53 into which the rotor shaft 61 is screwed, and a guide recess 52 and a stepping motor 6 in a case 62 described later. A communication hole 54 that communicates with the space is formed.

  The stepping motor 6 includes a rotor shaft 61, a case 62, a magnet rotor 63, and a stator coil (not shown). In the case 62, a magnet rotor 63 whose outer periphery is magnetized in multiple poles is rotatably provided, and a rotor shaft 61 is fixed to the magnet rotor 63. A stator coil is disposed on the outer periphery of the case 62, and the stepping motor 6 rotates the magnet rotor 63 according to the number of pulses when a pulse signal is given to the stator coil.

  On the outer peripheral surface of the rotor shaft 61, a male screw portion 611 that is screwed with the female screw portion 53 of the support member 5 is formed. When the stepping motor 6 is driven, the magnet rotor 63 and the rotor shaft 61 are rotated, and the rotor shaft 61 is moved in the Z direction by a screw feed mechanism constituted by the male screw portion 611 and the female screw portion 53. As a result, the valve holder 4 suspended from the rotor shaft 61 moves in the Z direction while being guided by the guide recess 52 of the support member 5, and the needle valve 31 of the valve element 3 is seated or separated from the seal portion 71. The valve port 70 is opened and closed. And the opening degree of the valve port 70 is controlled according to the position (lift amount) of the valve body 3 in the Z direction, and the flow rate of the fluid flowing through the valve port 70 is controlled.

  As shown in FIGS. 2 and 3, the valve seat member 7 is formed separately from the valve housing 2 by a metal member such as SUS or a resin member, for example, and is formed in a cylindrical shape as a whole. The portion is press-fitted into the cylindrical opening 22 of the valve housing 2 so as to abut the upper end of the joint pipe 23. A spiral groove 72 is formed on the outer peripheral surface of the valve seat member 7, and the groove 72 circulates about 1.5 times (about one and a half times) from the lower end to the upper end of the valve seat member 7. ing.

  The valve seat member 7 has a thick portion 7A on the upper half of the cylinder and a thin portion 7B on the lower half. The outer diameter of the valve seat member 7 is substantially constant, and the thin-walled portion 7B is thinner than the thick-walled portion 7A by expanding the inner diameter. The valve seat member 7 is formed with a stepped portion 7C on the inner peripheral surface between the thin portion 7B and the thick portion 7A.

  In the thick portion 7A, a mortar-shaped seal portion 71 on which the needle valve 31 is seated or separated is formed, and the valve port 70 is configured by the seal portion 71. The thick portion 7A is formed on the inner peripheral surface between the intermediate inner diameter portion 73 and the intermediate inner diameter portion 73 and the seal portion 71 having an inner diameter smaller than the thin portion 7B and larger than the seal portion 71. Second stepped portion 7D. The inner diameter of the seal portion 71 is the inner diameter of the portion having the smallest inner diameter (the lower end portion of the mortar) of the seal portion 71 and is equal to the port diameter. The intermediate inner diameter portion 73 has a substantially constant inner diameter and is formed in a cylindrical shape extending along the Z direction.

  The thin-walled portion 7B is inclined so that the outer peripheral surface is reduced in diameter toward the joint pipe 23 side in a state where the valve seat member 7 is not press-fitted into the cylindrical opening 22 of the valve housing 2, and the inner peripheral surface Extends along the Z direction (ie, has a substantially constant inner diameter). When the valve seat member 7 is press-fitted into the cylindrical opening 22, the thin-walled portion 7 </ b> B is deformed, and the inner peripheral surface is inclined so as to be reduced in diameter toward the joint pipe 23 side. Therefore, in a state where the valve seat member 7 is press-fitted into the cylindrical opening 22, the thin-walled portion 7B has an inclined portion 74 whose inner diameter increases toward the seal portion 71 on the inner peripheral surface, and the outer peripheral surface. Furthermore, it has the inclination part 75 from which an outer diameter becomes large as it goes to the seal part 71 side.

  The valve seat member 7 is mainly press-fitted with a thin portion 7 </ b> B into the cylindrical opening 22. At this time, the entire thin part 7B may be press-fitted and the thick part 7A may not be press-fitted, the entire thin part 7B and a part of the thick part 7A may be press-fitted, or the thin part 7B. Only a part of may be press-fitted.

  Here, the relationship between each part in the valve seat member 7 and the inner diameter (diameter) of the joint pipe 23 will be described. First, the inner diameter (port diameter) of the seal portion 71 is set to D1, the inner diameter of the intermediate inner diameter portion 73 is set to D2, the inner diameter of the upper end portion (the end portion on the thick portion 7A side) of the thin portion 7B is set to D3, and the thin portion 7B. The inner diameter of the lower end portion (the end portion on the joint pipe 23 side) is D4, and the inner diameter of the joint pipe 23 is D5. At this time, D1 <D2 <D5≈D4 <D3 holds. In order to increase the flow rate of the motor-operated valve 1 and to secure the step heights of the stepped portions 7C and 7D, the ratio D1 / D5 of the inner diameter D1 of the seal portion 71 to the inner diameter D5 of the joint pipe 23 is 0.61 or more. And it is preferable that it is 0.88 or less. That is, if the inner diameter D1 of the seal portion 71 is too small with respect to the inner diameter D5 of the joint pipe 23, the flow rate of the motor-operated valve 1 decreases, and the inner diameter D1 of the seal portion 71 is too large with respect to the inner diameter D5 of the joint pipe 23. And the step heights of the stepped portions 7C and 7D become low.

  As described above, since the inner diameter D4 of the lower end portion of the thin wall portion 7B and the inner diameter D5 of the joint tube 23 are substantially equal, the inner surface of the thin wall portion 7B is smoothly continuous with the inner surface of the joint tube 23. doing.

  Next, a method for fixing the joint pipe 23 to the cylindrical opening 22 by brazing will be described. First, as shown in FIG. 4, the cylindrical opening 22 is directed upward, and the annular brazing material 100 is placed outside the joint pipe 23 and in the vicinity of the boundary between the joint pipe 23 and the cylindrical opening 22. Place in and melt. The molten brazing material descends due to gravity and capillary action, and penetrates between the outer peripheral surface of the joint tube 23 and the inner peripheral surface of the cylindrical opening 22 as shown by arrows in FIG.

  Furthermore, a part of the molten brazing material passes between the end of the joint pipe 23 and the end of the valve seat member 7, travels inward in the radial direction, and reaches the inner peripheral surface side of the valve seat member 7. Sometimes. The brazing material that has reached the inner peripheral surface side of the valve seat member 7 further descends due to gravity and accumulates in the stepped portion 7C and solidifies. The brazing material further lowered without being accumulated in the stepped portion 7C accumulates in the second stepped portion 7D and solidifies. When all the brazing materials are solidified, fixing of the joint pipe 23 to the cylindrical opening 22 is completed.

  In the refrigeration cycle system described later, the motor-operated valve 1 mainly has a joint pipe 21 connected to the outdoor heat exchanger side and a joint pipe 23 connected to the indoor heat exchanger side. In the motor-operated valve 1, the fluid (refrigerant) flows in from the joint pipe 21 and flows out of the joint pipe 23, and the fluid flows in from the joint pipe 23. It is used for control of two types of flow, that is, the second flow that flows out from the joint pipe 21 (the flow indicated by the broken arrow in FIG. 1).

  The motor-operated valve 1 as described above is used as an expansion valve in a refrigeration cycle system as shown in FIG. 5, for example. In FIG. 5, reference numeral 200 denotes an outdoor heat exchanger mounted on the outdoor unit, 300 denotes an indoor heat exchanger mounted on the indoor unit, 400 denotes a flow path switching valve constituting a four-way valve, and 500 denotes a compressor. The motor-operated valve 1, the outdoor heat exchanger 200, the indoor heat exchanger 300, the flow path switching valve 400, and the compressor 500 are each connected by a conduit as shown in the figure to constitute a heat pump type refrigeration cycle. The accumulator, pressure sensor, temperature sensor, etc. are not shown.

  According to this embodiment, there are the following effects. That is, the stepped portion 7 </ b> C is formed on the inner peripheral surface of the valve seat member 7, so that when the joint pipe 23 is brazed to the cylindrical opening 22, the brazing material is on the inner peripheral surface side of the valve seat member 7. Even if it flows into the brazing material, the brazing material accumulates in the stepped portion 7C and can reach the seal portion 71. Further, since the thin portion 7B is formed closer to the joint pipe 23 than the thick portion 7A where the seal portion 71 is formed, the thin portion 7B can be easily press-fitted into the cylindrical opening.

  Further, since the intermediate inner diameter portion 73 is formed in the thick portion 7A, it is possible to suppress a sudden change in inner diameter between the seal portion 71 and the thin portion 7B, and the fluid passes through the valve seat member 7. In this case, turbulence is less likely to occur, and noise can be suppressed. At this time, both of the stepped portion 7C between the thick portion 7A and the thinned portion 7B and the second stepped portion 7D in the thickened portion A are portions where the brazing material is accumulated, and has a single stepped portion. However, the total amount of brazing material that can be stored is difficult to reduce.

  In addition, since the inner peripheral surface of the thin wall portion 7B is smoothly continuous with the inner peripheral surface of the joint pipe 23, turbulent flow is unlikely to occur between the valve seat member 7 and the joint pipe 23 when the fluid passes, and noise is reduced. Can be suppressed.

  Further, since the outer peripheral surface of the thin wall portion 7B is inclined so as to be reduced in diameter toward the joint pipe 23 side, the thin wall portion 7B can be easily press-fitted into the cylindrical opening portion 22.

  In addition, the motor-operated valve 1 including the valve seat member 7 as described above suppresses the brazing material from reaching the seal portion 71, can easily press-fit the valve seat member 7, Since the strain is difficult to be transmitted, the cut-off property is improved. By using such a motor-operated valve 1 as an expansion valve in the refrigeration cycle system, it is possible to suppress a decrease in operating efficiency of the refrigeration cycle system.

  In addition, this invention is not limited to the said embodiment, Including other structures etc. which can achieve the objective of this invention, the deformation | transformation etc. which are shown below are also contained in this invention.

  For example, in the embodiment, the intermediate inner diameter portion 73 and the second stepped portion 7D are formed in the thick portion 7A, but the difference between the inner diameter D3 of the thin portion 7B and the inner diameter D1 of the seal portion 71 is small. If the step height of the stepped portion 7C is low and noise is unlikely to occur, the intermediate inner diameter portion and the second stepped portion may not be formed.

  Moreover, in the said embodiment, the inner diameter D4 of the lower end part of the thin part 7B and the internal diameter D5 of the joint pipe 23 are substantially equal, and the inner peripheral surface of the thin part 7B continues smoothly with the inner peripheral surface of the joint pipe 23. However, the inner diameter of the thin wall portion may be set to an appropriate size in order to obtain a desired flow rate and a step height of the step portion. For example, when the flow rate is increased by increasing the inner diameter of the seal portion or when the step height of the step portion is ensured, the inner diameter of the thin portion may be larger than the inner diameter of the joint pipe.

  In the above embodiment, the outer peripheral surface of the thin wall portion 7B is inclined so as to be reduced in diameter toward the joint pipe 23 side. However, the thin wall portion has a substantially constant inner diameter and outer diameter. Then, it may be formed in a cylindrical shape. According to such a configuration, it is easy to increase the contact area between the outer peripheral surface of the thin portion and the inner peripheral surface of the cylindrical opening after press-fitting, and the displacement of the valve seat member can be suppressed.

  In addition, the best configuration, method and the like for carrying out the present invention have been disclosed in the above description, but the present invention is not limited to this. That is, the invention has been illustrated and described primarily with respect to particular embodiments, but may be configured for the above-described embodiments without departing from the scope and spirit of the invention. Various modifications can be made by those skilled in the art in terms of materials, quantity, and other detailed configurations. Therefore, the description limiting the shape, material, etc. disclosed above is an example for easy understanding of the present invention, and does not limit the present invention. The description by the name of the member which remove | excluded the limitation of one part or all of such is included in this invention.

DESCRIPTION OF SYMBOLS 1 Motorized valve 2 Valve housing 22 Cylindrical opening 23 Joint pipe 3 Valve body 7 Valve seat member 70 Valve port 71 Sealing part 73 Middle inner diameter part 7A Thick part 7B Thin part 7C Step part 7D 2nd step part

Claims (5)

A motor-operated valve that opens and closes a valve port by connecting a joint pipe to a cylindrical opening of a valve housing, press-fitting a valve seat member, and seating or separating a valve body on a seal portion of the valve seat member. ,
The valve seat member includes a thick portion in which the seal portion having an inner diameter smaller than that of the joint pipe is formed, and a thin portion in which the inner diameter is increased while being formed closer to the joint pipe than the thick portion. A motor-operated valve comprising: a step portion formed on an inner peripheral surface between the thin portion and the thick portion.   The thick portion is an intermediate inner diameter portion having an inner diameter smaller than the thin portion and larger than the seal portion, and a second inner portion formed between the intermediate inner diameter portion and the seal portion. The motor-operated valve according to claim 1, further comprising a step portion.   The motor-operated valve according to claim 1 or 2, wherein the thin portion has an inner diameter such that an inner peripheral surface thereof is smoothly continuous with an inner peripheral surface of the joint pipe.   The motor-operated valve according to any one of claims 1 to 3, wherein the thin portion is inclined so that at least an outer peripheral surface thereof is reduced in diameter toward the joint pipe side.   A refrigeration cycle system including a compressor, a condenser, an expansion valve, and an evaporator, wherein the motor-operated valve according to any one of claims 1 to 4 is used as the expansion valve. A refrigeration cycle system characterized by that.

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