JP3563595B2 - Electric valve and its assembly method - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electronically controlled expansion valve used during a refrigeration cycle used for an air conditioner.
[0002]
[Prior art]
Conventionally, this type of motor-operated valve has been considered to have a configuration as disclosed in JP-A-7-310844.
[0003]
Hereinafter, the configuration will be described with reference to FIG. A coil 113 fixed inside the cylindrical case 101 and a ball 11 at the center of the lower end provided inside the coil 113
7, a valve body 119 via a compression coil spring 118, a screw 129 on the outer periphery, a rotor 114 on the upper half outer periphery, and a vertically moving rotation while rotating by energizing the coil 113. A shaft 115, a chamber 133 provided at a central portion provided at a lower end portion of the case 101, a female screw 128 screwable with the male screw 129 at an upper opening thereof, and a valve seat 125 and a valve provided at a lower portion of the chamber 133. A valve body 123 having an opening 126 and an opening 132 on the side of the chamber 133. The external thread 129 of the rotary shaft 115 is screwed into an internal thread 128 of the valve body 123, and the valve element 119 is connected to the valve. In the motor-operated valve provided corresponding to the seat 125, a bracket 107 is provided at an upper end of the coil 113 and the rotation of the bracket 107 is performed. A shaft 108 having a length slightly below the intermediate portion of the coil 113 is fixed to a central portion corresponding to the axis of the shaft 115 in a drooping manner, while a deep hole 134 is provided in the center of the upper half of the rotating shaft 115. The deep hole 134 is rotatably inserted into the hanging shaft 108.
[0004]
With the above configuration, the vertical movable range of the valve element 119 is limited by the valve element 119 contacting the valve seat 125 at the lower limit and the shaft 108 contacting the spring 116 at the upper limit. Further, since the rotation shaft 115 is supported by the shaft 108 having a one-sided support structure, the rotation shaft 115 has a certain degree of flexibility against misalignment between the female screw 128 and the shaft 108.
[0005]
[Problems to be solved by the invention]
First, such a conventional motor-operated valve has a problem in that the distance between the valve seat and the shaft, which limits the vertical movable range of the valve body, is determined via the plate, the coil, and the bracket, and thus varies.
[0006]
Second, there is a problem that a stable rotation torque cannot be obtained when the axis of the rotation shaft and the axis of the coil are shifted.
[0007]
Third, there is a problem that the number of parts is large and assembly is difficult. An object of the present invention is to solve such a conventional problem, and an object of the present invention is to provide a motor-operated valve capable of performing a vertical movement range with little variation, a stable rotation torque and simple assembly, and a method of assembling the same. .
[0008]
[Means for Solving the Problems]
In order to achieve the above object of the present invention, an upper cover of a cylindrical case, a coil fixed inside the case, a valve portion and a male thread portion inside the coil, and an upper half rotor are integrally formed. A shaft that moves up and down while rotating by energizing the coil, and a female screw at the lower end of the case that has a chamber at the center and that can be screwed to the male screw at the upper opening. And a valve body having a valve seat and a valve port at the lower part of the chamber and having an opening at a side of the chamber, and the male screw of the shaft is screwed into the female screw of the valve body. In the electric valve provided with the valve portion corresponding to the valve seat, the valve body is provided with a coil cover portion that supports the coil from the outer periphery by processing coaxially with the chamber and the valve port, and the shaft is provided from outside. A shaft bearing portion to be held and a bearing provided coaxially with the shaft bearing portion and provided with a cutout portion that can be fitted to the coil cover portion of the valve body are provided, and the upper limit of the vertical movement range is limited on the shaft. A stopper portion is provided.
[0009]
Another means is to integrate the valve body and the case.
[0010]
Another means is to center and fix the coil with reference to both or one of the chamber and the coil cover of the valve body.
[0011]
Another means is to form a plurality of holes in the insertion surface of the jig for centering, and to allow air to be blown out of the holes, thereby forming a gap between the insertion surface of the jig, the coil, and the valve body. It keeps them evenly.
[0012]
As described above, according to the present invention, it is possible to obtain a motor-operated valve and a method for assembling the same, which enable a vertically movable range with little variation, a stable rotational torque, and simple assembly.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
The present invention has an upper cover of a cylindrical case, a coil fixed inside the case, a valve portion and a male screw portion inside the coil, and an upper half rotor integrally provided, and A shaft that moves up and down while rotating by energization, and a receiving portion having a chamber at a central portion thereof and having an internal thread that can be screwed into the male screw at an upper opening thereof at a lower end of the case, and a lower portion of the chamber. A valve body having a valve seat and a valve port, and having an opening on a side of the chamber, wherein an external thread of the shaft is screwed into an internal thread of the valve body, and the valve section is made to correspond to the valve seat. In the electric valve provided, a coil cover portion that supports the coil from the outer periphery by processing the valve body coaxially with the chamber and the valve port, and a shaft bearing portion that supports the shaft from outside, By providing a bearing provided with a cutout part that can be fitted to the coil cover part of the valve body, which is machined coaxially with the shaft bearing part, and by providing the shaft with a stopper part that limits the upper limit of the vertical movement range, By directly fixing the bearing and the valve body, a variation factor of the distance between the stopper portion and the valve seat is reduced, and the chamber and the coil cover portion are coaxially processed to be inserted and fixed in the coil cover portion. This has the effect of reducing the cause of axial misalignment between the coil shaft and the shaft shaft and facilitating assembly.
[0014]
In addition, the valve body and the case are integrated, which has the effect of reducing welding locations and facilitating assembly.
[0015]
Further, by centering and fixing the coil with reference to both or one of the chamber of the valve body and the coil cover portion, it is possible to correct the misalignment of the axis between the outer circumference and the inner circumference of the coil.
[0016]
In addition, a plurality of holes are formed in the insertion surface of the jig for centering, and the air is blown out from the holes, thereby preventing the jig from hitting the coil and the reference surface. Having.
[0017]
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0018]
【Example】
( Reference Example 1)
As shown in FIGS. 1 and 2, an upper cover 2 is welded to an upper end of a cylindrical case 1 and a valve body 7 is welded to a lower end, and a terminal 3 is fixed to the upper cover 2 by bonding or crimping. Have been. Inside the case 1, a coil 13 formed by a magnetic pole plate 11 and a bobbin 12 is fixed, and a coil cover part 14 fitted to the valve body 7, a valve part 15 and a male thread part 16 are provided. A shaft bearing portion 17 for supporting an outer peripheral portion of an upper end of the shaft 5 which moves up and down while rotating by energizing the coil 13 and a stopper portion which limits the upper limit of the vertical movement range of the shaft 5 The bearing 4 comprises a bearing 18.
[0019]
The valve body 7 has a chamber 19 at the center and a receiving portion 8 having a female thread portion 21 which can be screwed into the male thread portion 16 is inserted into an upper opening thereof, and a valve seat is provided at a lower portion of the chamber 19. The chamber 19 has an opening 24 on the side thereof. The pipe a9 is welded to the opening 24 and the pipe b10 is welded to the valve port 23, so that the flow rate and pressure of the fluid flowing from the pipe a9 or the pipe b10 change the opening area of the valve port 23. Control.
[0020]
Here, the shapes of the bearing 4 and the valve body 7 and an assembling method will be described in detail with reference to FIG.
[0021]
The bearing 4 is formed by coaxially processing the shaft bearing portion 17 and the coil cover portion 14 so that the coil 13 is inserted and fixed by a means such as adhesion, so that the processing tolerance of the inner and outer diameters of the coil 13 is improved. Thus, centering can be performed within the range of the clearance between the outer diameters of the coil cover portion 14 and the coil 13. Further, the valve body 7 has a cutout portion 25 into which the coil cover portion 14 of the bearing 4 can be fitted so as to be coaxial with the chamber 19 and the valve port 23.
[0022]
With the above configuration, the axis of the shaft bearing portion 17 of the bearing 4 and the axes of the chamber 19 and the valve port 23 can be centered within the clearance range of the fitting portion. Further, the dimensions of the lower end surface of the coil cover portion 14 from the stopper portion 18 of the bearing 4 and the contact surface of the notch portion 25 of the valve body 7 with the lower end surface of the coil cover portion 14 determine the valve seat 22. And the vertical movable range of the shaft 5 can be managed in a tolerance range of three dimensions of the length of the shaft 5.
[0023]
( Reference Example 2)
The same reference numerals are given to the same parts as in Reference Example 1, and the description is omitted.
[0024]
Further, in Reference Example 2 of the present invention will be described differences from the reference example 1. As shown in FIG. 3, a notch is provided in the shaft 29 as a stopper 26 that limits the upper limit of the vertical movement range of the shaft 29. The bearing 27 includes a coil cover 14 for fixing the coil 13 and fitting to the valve body 7, and a shaft bearing 28 for supporting an outer peripheral portion of an upper end of the shaft 29.
[0025]
With the above configuration, the dimensions from the lower end surface of the shaft bearing portion 28 of the bearing 27 to the lower end surface of the coil cover portion 14 and the contact surface of the notch portion 25 of the valve body 7 with the lower end surface of the coil cover portion 14 are used. Variations in the vertical movable range of the shaft 29 can be managed within a tolerance range of three dimensions of the size of the seat 22 and the size of the valve portion 15 to the stopper portion 26 of the shaft 29.
[0026]
( Reference Example 3)
The same parts as in Reference Examples 1 and 2 are denoted by the same reference numerals, and description thereof is omitted.
[0027]
Further, in Reference Example 3 of the present invention will be described with reference to Reference Example 2 part becomes same in Reference Example 1.
[0028]
As shown in FIG. 4, when the coil 13 is inserted into the coil cover portion 14 of the bearing 27 and fixed by means such as bonding, a centering process for centering the inner diameter of the coil 13 with the coil cover portion 14 as a reference plane. By inserting the tool 30, centering within the range of the clearance between the jig 30 and the coil 13 and the clearance between the coil cover portion 14 becomes possible.
[0029]
(Example 1 )
The same parts as in Reference Examples 1 and 2 are denoted by the same reference numerals, and description thereof is omitted.
[0030]
In Example 1 of the present invention will be described Differences from Example 2. As shown in FIG. 5, the valve body 31 is formed by processing a coil cover 32 for fixing the coil 13 coaxially with the chamber 19 and the valve port 23, and a notch portion into which the coil cover 32 can be fitted. 33 is provided on the bearing 34 by processing coaxially with the shaft bearing portion 28.
[0031]
With the above configuration, the centering within the processing tolerance of the inner and outer diameters of the coil 13 and the clearance between the outer diameter of the coil 13 and the coil cover 32 can be performed. In addition, the shaft of the shaft bearing portion 28 of the bearing 34 and the shaft of the chamber 19 and the valve port 23 can be centered within the clearance range of the fitting portion. Further, the dimension of the contact surface between the lower end surface of the shaft bearing portion 28 of the bearing 34 and the upper end surface of the coil cover portion 32 of the notch portion 33 and the valve from the upper end surface of the coil cover portion 32 of the valve body 31 Variations in the vertical movable range of the shaft 29 can be managed within a tolerance range of three dimensions of the size of the seat 22 and the size of the valve portion 15 to the stopper portion 26 of the shaft 29.
[0032]
(Example 2 )
The same parts as in Reference Examples 1 and 2 and Example 1 are denoted by the same reference numerals, and description thereof is omitted.
[0033]
In the second embodiment of the present invention, differences from the first embodiment will be described. As shown in FIG. 6, the valve body 35 is shaped so that the groove 36 for releasing the lead wire of the coil 13 and the upper cover 2 to which the terminal 3 is adhered can be welded to the upper end.
[0034]
According to the above configuration, the number of components and the number of welding points can be reduced.
[0035]
(Example 3 )
The same parts as in Reference Examples 1 and 2 and Embodiments 1 and 2 are denoted by the same reference numerals, and description thereof is omitted.
[0036]
In the third embodiment of the present invention, description will be made using the components of the first embodiment, but the same applies to the second embodiment.
[0037]
As shown in FIG. 7, when the coil 13 is inserted into the coil cover portion 32 of the valve body 31 and fixed by means such as bonding, the centering of the inner diameter of the coil 13 is performed using the side surface of the chamber 19 as a reference surface. By inserting the tool 37, centering within the range of the clearance between the jig 37 and the inner diameter of the coil 13 and the side surface of the chamber 19 becomes possible.
[0038]
The same effect can be obtained by using the coil cover 32 as a reference plane.
[0039]
(Example 4 )
The same parts as in Reference Examples 1 and 2 and Embodiments 1 and 2 are denoted by the same reference numerals, and description thereof is omitted.
[0040]
In Example 4 of the present invention will be described with reference to components of Example 3 the same Reference Example 3.
[0041]
As shown in FIG. 8, when the coil 13 is inserted into the coil cover 32 of the valve body 31 and fixed by means such as bonding, a centering process of the inner diameter of the coil 13 is performed with the side surface of the chamber 19 as a reference surface. The tool 38 is inserted. The jig 38 has a hollow inside, and when compressed air is sent into the inside, air blows out from the plurality of holes 39.
[0042]
With the above configuration, it is possible to reduce the amount of misalignment due to the inner diameter of the jig 38 and the coil 13 and the side contact of the side surface of the chamber 19, and more accurate centering becomes possible.
[0043]
【The invention's effect】
As is clear from the above embodiments, according to the present invention, it is possible to provide a motor-operated valve capable of assembling the motor-operated valve in which the vertical movable range with little variation, stable rotational torque, and simple assembly are possible.
[Brief description of the drawings]
Motorized Figure 1 Reference sectional view of an electric valve of Example 1 assembled view of FIG. 2 the electric valve cross-sectional view of an electric valve of Figure 3 the reference example 2 [4] the Example 3 of the present invention FIG. 5 is a sectional view of a motor-operated valve according to the first embodiment. FIG. 6 is a cross-sectional view of a motor-operated valve according to the second embodiment. FIG. 7 is an assembly diagram of a motor-operated valve part according to the third embodiment. 8: Assembly drawing of the motor-operated valve part of Embodiment 4 [FIG. 9] Cross-sectional view of conventional motor-operated valve
DESCRIPTION OF SYMBOLS 1 Case 2 Top cover 3 Terminal 4 Bearing 5 Shaft 6 Rotor 7 Valve main body 8 Receiving part 9 Tube a
10 tubes b
DESCRIPTION OF SYMBOLS 11 Magnetic pole plate 12 Bobbin 13 Coil 14 Coil cover part 15 Valve part 16 Male thread part 17 Shaft bearing part 18 Stopper part 19 Chamber 21 Female thread part 22 Valve seat 23 Valve port 24 Opening 25 Notch part 26 Stopper part 27 Bearing 28 Shaft Bearing 29 Shaft 30 Jig 31 Valve body 32 Coil cover 33 Notch 34 Bearing 35 Valve body 36 Groove 37 Jig 38 Jig 39 Hole

Claims (4)

An upper cover of a cylindrical case, a coil fixed inside the case, a valve portion and a male thread portion inside the coil, an upper half rotor integrally provided, and rotated by energizing the coil. A shaft that moves up and down, and a lower end of the case, a receiving portion having a chamber at the center and having a female screw that can be screwed with the male screw in an upper opening thereof, and a valve seat at a lower portion of the chamber. An electric motor comprising a valve body having a valve port and having an opening on a side portion of the chamber, wherein an external thread of the shaft is screwed into an internal thread of the valve body, and the valve section is provided corresponding to a valve seat. In the valve, the valve body is provided with a coil cover portion for supporting the coil from the outer periphery by processing coaxially with the chamber and the valve port, and a shaft bearing portion for supporting the shaft from the outside; The bearing is provided coaxially with the portion and provided with a notch portion that can be fitted with the coil cover portion of the valve body, and the shaft is provided with a stopper portion that limits an upper limit of a vertical movement range. valve. Electric valve according to claim 1, wherein the integrated valve body and casing. As both or either reference one of the chambers and the coil cover portion of the valve body, the assembling method of claims 1 and 2 an electric valve according to, characterized in that fixed to the centering of the coil. 4. The method according to claim 3 , wherein a plurality of holes are formed in the insertion surface of the jig for centering, and air is blown out of the holes.

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