JP2021517948A - Electronic expansion valve - Google Patents

Abstract

An electronic expansion valve includes a screw (6), a nut (8) fitted on the outside of the screw (6), a stopper (12) installed on an upper outer ring of the nut (8), and a nut. A magnetic rotor (7) fitted to the outer ring of (8) is included, and at least one first bonding surface (84) is installed on the outer peripheral wall of the nut (8), and the inside of the magnetic rotor (7) is provided. At least one second bonding surface (73) that engages with and limits the first bonding surface (84) is installed on the peripheral wall, and the first bonding surface (84) and the second bonding surface (84) are bonded. The surfaces of the mating surfaces (73) are laminated and the nut (8) and magnetic rotor (7) are mounted and positioned using the engagement of the first laminating surface (84) and the second laminating surface (73). By facilitating the process, the assembly process is simplified, the production efficiency is improved, and the production cost is reduced. [Selection diagram] Fig. 2

Description

The present invention relates to the technical field of valves, and particularly to electronic expansion valves.

As a new control component, the electronic expansion valve has already gone beyond the concept of the throttle mechanism, is an important part of the intelligent refrigeration system, and is also an important means and guarantee to truly realize the optimization of the refrigeration system. It is also a symbol of the mechanical and electrical integration of the refrigeration system, and is being applied in more and more fields.

The electronic expansion valve for adjusting the flow rate of the refrigerant in a refrigerating system such as an air conditioner includes a valve body member and a coil, and the flow rate of the refrigerant in the refrigerating system is large depending on the degree of opening and closing of the spindle in the valve body member driven by the coil. Adjust the temperature to achieve the effect of temperature control.

A Chinese patent application (Application No. 20101051523.4.1) discloses an electronic expansion valve (FIG. 1) composed of a valve seat assembly, a nut assembly, a spindle screw rod assembly and a rotor assembly. In the implementation process, the intake pipe 14 is fitted into the side hole of the valve seat 12, the exhaust pipe 13 is press-fitted into the protruding side of the valve seat core 11, and then the production is completed by furnace welding so as to be integrated. In the process of manufacturing the nut assembly, the connecting plate 31 is first injection molded into the nut by an injection molding machine, then the stopper spring 33 and the stopper ring 34 are attached, and finally laser welding is performed on the valve seat. The spindle screw rod assembly is composed of six parts, a spindle 21, a spring 25, a bush 24, a pressing sleeve 22, a steel ball and a screw rod 23, and is assembled and integrated by two laser welding. After the magnetic rotor 41 and the guide plate 42 are tightly fitted, they are integrated by laser welding, then assembled into the spindle screw rod assembly, laser welded again, and finally the sleeve and valve seat are welded by laser welding. And the valve body production is completed. In the entire implementation process, there are many assembly processes, many quality control points, and there are as many as six places where laser welding is used, which is disadvantageous for product quality control and high manufacturing costs.

An object of the present invention is to provide an electronic expansion valve that simplifies the assembly process, reduces the use of parts, has fewer quality control points, has fewer steps, improves fabrication efficiency, and reduces costs.

In order to solve the above problems, the present invention is one aspect of the present invention.
With the screw assembly including the screw,
The outer wall of the nut includes at least one first, including a nut fitted on the outside of the screw, a stopper installed on the upper outer ring of the nut, and a rotor assembly containing a magnetic rotor fitted on the outer ring of the nut. On the inner peripheral wall of the magnetic rotor, at least one second bonding surface that engages with and limits the first bonding surface is installed, and the first bonding surface and the first bonding surface are installed. By providing an electronic expansion valve in which the surfaces of the two bonded surfaces are bonded together, the engagement of the first bonded surface and the second bonded surface facilitates the mounting and positioning of the nut and the magnetic rotor. The assembly process is simplified, manufacturing efficiency is improved and production cost is reduced.

The present invention, as another aspect,
A valve seat assembly including a valve seat and a first connecting pipe connected to one side of the valve seat and a second connecting pipe connected to the lower part of the valve seat.
A screw assembly including a screw attached to the valve seat,
Including the spindle assembly including the spindle installed in the screw,
Inside the valve seat assembly, a valve chamber that communicates with the first connecting pipe and the second connecting pipe is installed, and the first valve opening is located where the valve chamber and the second connecting pipe communicate with each other. In the valve chamber, a pilot spool having a second valve opening is installed, the pilot spool is mounted on the spindle and the spindle is used as a guide, and in the first state, the spindle is a pilot spool. Is brought into contact with the first valve port, and the second valve port is conducted so that the first connecting pipe is conducted to the second connecting pipe via the second valve port, and the second valve port is conducted. In the second state, the spindle closes the second valve port and provides an electronic expansion valve that guides the pilot spool to separate it from the first valve port, switching the flow rate of the two flow paths by the pilot spool. The check valve function can be realized without installing multiple expansion valves, the control of the system is simplified, the use of parts is reduced, the assembly process is simplified, the number of steps is reduced, and the production is completed. Improve efficiency and reduce costs.

The present invention, as yet another aspect,
With the screw assembly including the screw,
Includes a nut fitted on the outside of the screw, a stopper installed on the upper outer ring of the nut, and a rotor assembly containing a magnetic rotor fitted on the outer ring of the nut, and the nut and / or screw includes the nut and screw. A limiting member is provided to prevent the relative movement of the nut in the circumferential direction, and the blocking action of the limiting member can make it difficult to rotate the relative displacement between the nut and the screw, resulting in electronic expansion. Improves the reliability of valve operation, simplifies the assembly process, improves fabrication efficiency and reduces production costs.

It is a structural conceptual diagram which roughly showed the electronic expansion valve by a conventional form. It is a cross-sectional structure conceptual diagram which roughly showed the electronic expansion valve by embodiment of this invention. It is sectional drawing which showed the rotor assembly of the electronic expansion valve according to embodiment of this invention schematic. It is sectional drawing which showed the nut inner hole of the electronic expansion valve by embodiment of this invention schematicly. It is a structural conceptual diagram which roughly showed the nut of the electronic expansion valve by embodiment of this invention. It is a structural conceptual diagram which roughly showed the screw of the electronic expansion valve by embodiment of this invention. It is a structural conceptual diagram before injection molding which schematically shows the screw of the electronic expansion valve by embodiment of this invention. It is sectional drawing which showed the magnetic rotor of the electronic expansion valve according to the embodiment of this invention schematically. It is a structural conceptual diagram which roughly showed the stopper of the electronic expansion valve by embodiment of this invention. It is a structural conceptual diagram which generally showed the magnetic rotor of the electronic expansion valve by embodiment of this invention. It is a structural conceptual diagram which roughly showed the magnetic rotor of another electronic expansion valve by embodiment of this invention. It is an enlarged view which showed the part A of FIG. 11 schematicly. It is sectional drawing which showed the other electronic expansion valve according to the embodiment of this invention schematic. It is a partially enlarged view which shows the part A of FIG. 13 schematicly. It is a structural conceptual diagram which roughly showed the pilot spool in another electronic expansion valve by embodiment of this invention. It is sectional drawing which showed the pilot spool in another electronic expansion valve according to the embodiment of this invention schematically. It is a structural conceptual diagram which roughly showed the screw assembly in another electronic expansion valve by embodiment of this invention. It is a cross-sectional structure conceptual diagram which roughly showed the ventilation from the 1st connection pipe to the 2nd connection pipe in another electronic expansion valve by embodiment of this invention. It is sectional drawing which showed the ventilation from the 2nd connection pipe to the 1st connection pipe in another electronic expansion valve by embodiment of this invention schematicly.

Hereinafter, examples of the present invention will be described in detail, but the present invention can be carried out in various forms limited and covered by the claims.

As shown in FIGS. 2 to 12, according to the embodiment of the present invention, the electronic expansion valve is:
A screw assembly 6 including a screw and a screw assembly 6
The nut 8 includes a nut 8 fitted on the outside of the screw, a stopper 12 installed on the upper outer ring of the nut 8, and a rotor assembly including a magnetic rotor 7 fitted on the outer ring of the nut 8, and the nut 8 is injected with engineering plastic. Molding is possible, the outer peripheral wall of the nut 8 is provided with at least one first bonding surface 84, and the inner peripheral wall of the magnetic rotor 7 is engaged with the first bonding surface 84. At least one second bonding surface 73 is installed, the surfaces of the first bonding surface 84 and the second bonding surface 73 are bonded, and the first bonding surface 84 and the second bonding surface 84 are bonded. The number of mating surfaces 73 may be the same, and the contact between the surfaces facilitates positioning during mounting, simplifies the assembly process, improves manufacturing efficiency, and reduces production costs.

By matching the shapes of the first bonding surface 84 and the second bonding surface 73, better bonding becomes possible, and the second bonding surface 73 located on the convex rib 71 is a flat surface or A curved surface can be adopted, and the corresponding first bonding surface 84 is also a flat surface or a curved surface. For example, when a concave surface is adopted for the second bonding surface 73, the first bonding surface 84 corresponds. A convex surface is adopted, and a gap fitting, an intermediate fitting, or a tightening fitting is adopted between the first bonding surface 84 and the second bonding surface 73, and the present invention is not limited thereto.

As shown with reference to FIGS. 9, 10 and 11, the first bonding surface 84 and the second bonding surface 73 are less likely to be displaced from each other. The mating surface 84 is provided with a rod-shaped protrusion 85 along the vertical direction, and the operation of engaging the rod-shaped protrusion 85 with the second laminating surface 73 can serve as a guide and a limiting function, and the first When the surfaces of the bonding surface 84 and the second bonding surface 73 are bonded together, the rod-shaped protrusion 85 is housed in the groove 72, and when assembling, the nut 8 is first mounted in the magnetic rotor 7 and then inside the magnetic rotor 7. By engaging the second bonding surface 73 provided in the above and the first bonding surface 84 provided outside the nut 8, the circumferential direction of the magnetic rotor 7 is fixed, and the rod-shaped protrusion 85 and the concave groove are formed. By engaging with the 72, the positioning accuracy of the assembly can be improved, and further, the manufacturing accuracy of the first bonded surface 84 and the second bonded surface 73 can be lowered, and the feasibility of the process can be improved. can.

The length dimension of the rod-shaped protrusions 85 for each of the first bonding surfaces 84 may be different, may be paired, and the engagement relationship between the rod-shaped protrusions 85 having a large dimension and the groove 72 may be different. Is a tight fit, but the engagement relationship between the rod-shaped protrusion 85 and the groove 72 having a small size may be a gap fit, and is not limited thereto.

The stopper 12 employs a metal sheet, a plastic sheet, or a rubber sheet and can be flexibly selected, and the stopper 12 is not limited thereto.

As shown with reference to FIGS. 4, 5 and 9, a lock diameter portion 83 and an enlarged portion 81 are provided at the tip of the nut 8, and the diameter of the lock diameter portion 83 is larger than the diameter of the enlarged portion 81. The stopper 12 includes a disc-shaped portion 121 and a warp member 122, the disc-shaped portion 121 is in contact with the end face 75 of the magnetic rotor 7, and the warp member 122 is fitted to the lock diameter portion 83. When the outer warp member 122 is fastened, an elastic deformation urging force is generated and is locked to the lock diameter portion 83, and the presence of the enlarged portion 81 can prevent the stopper 12 from falling off from the lock diameter portion 83, via the stopper 12. The axial movement of the magnetic rotor 7 can be restricted, and in particular, the downward movement can be restricted, thereby realizing the fixing effect of the magnetic rotor 7.

As for the structure of the outer warp member 122, a cylindrical shape may be adopted, or at least two bent portions may be adopted, and the lock diameter portion 83 may be clamped at the bent portions. The four bent portions are adopted and installed symmetrically around the central hole of the disc-shaped portion 121, and the central hole is used to facilitate the penetration of the lock diameter portion 83 and the enlarged portion 81.

As shown with reference to FIGS. 4 and 5, the nut 8 in the embodiment of the present invention has an inner hole for attaching the screw 6, and the screw guide portion 810, the female screw portion 89, and the preload spring attachment are provided in the inner hole. A portion 88 and a spindle guide portion 82 are provided in order, and here, an inner diameter D1 of the screw guide portion, a small diameter D2 of the female screw portion 89, an inner diameter D3 of the preload spring mounting portion 88, and an inner diameter D4 of the spindle guide portion 82 are provided. D1> D2> D3> D4 are satisfied, but in this embodiment, D4 can be selected from 2.09 mm, D3 can be selected from 4.30 mm, D2 can be selected from 4.36 mm, D1 can be selected from 5.18 mm, and the spindle guide portion 82 has a small nut. Corresponding to the holes, the screw 6 penetrates the nut holes and employs a stepped structure of inner diameter dimensions to facilitate limiting and mounting.

As shown with reference to FIG. 7, correspondingly, the screw 6 is provided with a screw portion 61, a smoothing guide portion 62, an injection molding joint portion 64, a positioning portion 65, and a guide portion 66 in this order. An annular groove 63 is provided in the molding joint portion 64 along the circumferential direction, and the strength of the injection molding portion is increased by facilitating adhesion by injection molding through the annular groove 63.

As shown with reference to FIG. 7, a D port 67 is provided on the side surface of the injection molding joint portion 64, and a notch having a shape other than the shape of the D port 67 (for example, a deformed notch or an asymmetric notch) is provided. Etc.), the stop block 15 is injection-molded to the screw 6 via the injection-molded joint portion 64, and the adoption of the D port 67 also enhances the adhesion by injection-molding and increases the strength of the injection-molded part. The structure of the annular groove 63 and the D port 67 may be used at the same time or may be adopted separately, but the structure is not limited thereto.

As shown with reference to FIG. 8, the nut 8 further has a stepped surface 86, which can be installed at the bottom of the nut 8, and the stepped surface 86 abuts on the end face 75 of the convex rib 71. Further, the stop block 15 is provided with a cam 151 on the side surface in the axial direction, and a stop cam 87 is provided on the bottom of the outer periphery of the nut 8, and the cam 151 is stopped when the electronic expansion valve is fully closed. It comes into contact with the 87 and realizes a stopping action.

Further, as shown with reference to FIGS. 9, 10 and 11, the height of the convex rib 71 is lower than the height of the magnetic rotor 7, and the convex rib 71 has both ends along the central portion of the magnetic rotor 7. Specifically, there are four convex ribs 71, and they are installed at equal intervals on the inner peripheral wall of the magnetic rotor 7, and there are four first bonding surfaces 84. And it is evenly distributed on the outer peripheral wall of the nut 8.

At the time of implementation, after the sleeve holder 5 and the valve seat are tightened and fitted, the welding ring is attached, then the first connecting pipe 1 and the second connecting pipe 2 are attached, and welding is completed by the tunnel furnace, and the screw assembly is completed. Consists of a screw 6 and a stop block 15 injection-molded therein. At the time of implementation, the screw assembly is tightened and fitted into the inner chamber of the valve seat to realize fixing, and the nut 8 is mounted in the magnetic rotor 7. Then, the second bonding surface 73 of the four convex ribs 71 provided in the magnetic rotor 7 and the four first bonding surfaces 84 provided outside the nut 8 are engaged with each other to cause magnetism. After fixing the circumferential direction of the rotor 7 and assembling, the positioning accuracy of the assembly can be improved by the engaging action of the rod-shaped protrusion 85 and the concave groove 72, and at the same time, the first bonding surface 84 and the second bonding surface 73 can be improved. Reduces the fabrication accuracy of the process and increases the feasibility of the process. Then, the stopper 12 is attached, and while the bent portion of the stopper 12 abuts on the lock diameter portion 83, the bent portion generates an elastic deformation urging force and is locked to the lock diameter portion 83, so that the enlarged portion 81 By preventing the stopper 12 from falling off, the downward movement of the magnetic rotor 7 in the axial direction can be restricted, and the magnetic rotor 7 can be further fixed. Next, the spindle, the preload spring 14, the gasket 13, and the rotor assembly can be fixed. The solids are assembled in order, and the stop block 15 installed on the nut 8 is replaced by the cam 151 on the stop block 15 installed on the screw assembly by the engaging action of the screw portion installed in the inner chamber of the nut 8 and the screw screw portion. The rotor assembly is screwed clockwise until it hits, and then rotated counterclockwise at the set angle of the rotor assembly. This process is called the pre-expansion valve initialization process, and the position of the rotor assembly remains unchanged. While holding, the stop block 9 is assembled, the stop block 9 and the spindle are gap-fitted, the spindle penetrates the nut small hole, and the stop block 9 and the end face 75 of the nut small hole are bonded to each other by laser welding. After fixing the stop block 9 and the spindle, then assembling the return spring 10, and press-fitting the sleeve 11, the sleeve 11 and the sleeve holder 5 are tightly fitted, and then connected by continuous laser welding to provide sealing performance. To secure.

As shown with reference to FIG. 13, specifically, the electronic expansion valve according to another embodiment of the present invention is
The valve seat 3, the first connecting pipe 1 connected to one side of the valve seat 3, the second connecting pipe 2 connected to the lower part of the valve seat 3, and the sleeve holder 5 installed on the valve seat 3. It is a valve seat assembly including, and specifically, after the sleeve holder 5 and the valve seat 3 are tightened and fitted, the welding ring is attached, and then the first connecting pipe 1 and the second connecting pipe 2 are attached. Install and complete the welding by the tunnel furnace, with the valve seat assembly,
A spindle assembly including a spindle 4 attached to the screw 6 and a preload spring 14 attached to the spindle 4.
A sleeve assembly including a stop block 9 attached to the top of the screw 6, a return spring 10 attached to the stop block 9, and a sleeve 11 externally fitted to the rotor assembly and connected to the sleeve holder 5.
A screw assembly including a screw 6 press-fitted into the valve seat and a stop block 15 attached to the screw 6, and the stop block 15 is installed on the screw 6 by injection molding, and at the time of implementation, the inside of the valve seat 5 Includes a screw assembly that is tightly fitted into the chamber to achieve fixation.

Inside the valve seat assembly, a valve chamber 55 communicating with the first connecting pipe 1 and the second connecting pipe 2 is installed, and the valve chamber 55 and the second connecting pipe 2 are communicated with each other. A first valve port 23 is provided, and a pilot spool 25 having a second valve port 51 is installed in the valve chamber 55, and the pilot spool 25 is mounted on the spindle 26 and guides the spindle 26. In the first state, the spindle 26 guides the pilot spool 25 to abut the first valve port 23, and the first connecting pipe 1 passes through the second valve port 51 and is second. The second valve port is conducted so as to be conducted to the connecting pipe 2, and in the second state, the spindle 26 closes the second valve port 51 and guides the pilot spool 25 to the first valve. Separated from the mouth, the pilot spool 25 realizes control of switching the flow rate of the two flow paths, the check valve function can be realized without installing multiple expansion valves, the control of the system is simplified, and the parts It reduces use, simplifies the assembly process, reduces steps, improves fabrication efficiency and reduces costs.

As shown in FIGS. 13, 14, 15 and 16, the pilot spool 25 is further installed on the side wall of the pilot spool 25 to communicate the first connecting pipe 1 and the second valve port 51. Further including at least one flow path hole 52 and a guide portion 53 installed at the other end of the pilot spool 25 and fitted to the spindle 26 to use the spindle 5 as a guide, the second valve port is a second valve port. Used to communicate with the connecting pipe, the guide portion 53 is mounted on the spindle 26 to use the spindle 26 as a guide, the flow path hole 52 is installed in the side wall of the pilot spool 25, and the first connecting pipe 1 and the first Used to communicate with the valve port 51 of 2, the pilot spool 25 is installed so as to surround one end of the pilot spool 25, is used to abut the first valve port 23, and has an outer end surface. The second valve port 51 and the flow path hole 52 form a connecting passage, including the taper 54 having a tapered structure.

As shown in FIG. 15, the number of flow path holes 52 may be a plurality, and in this embodiment, there are four flow path holes 52, and the four flow path holes 52 are the side walls of the pilot spool 25. Is evenly distributed in.

As shown with reference to FIGS. 13 and 14, a spindle taper 54 for contacting the second valve port 51 is provided at one end of the spindle 26, and the spindle taper 54 and the second valve are provided. A sealing action on the second valve opening is realized after the mouth 51 is brought into contact with the port 51.

As shown with reference to FIG. 16, the inner diameter D2 of the valve chamber 55 and the inner diameter D1 of the guide portion need to satisfy the relationship of D2> D1 in order to secure the distribution capacity.

As shown in FIGS. 13 and 17, a mounting cavity 91 for accommodating the spindle 26 and the guide portion 53 is provided at the lower end of the screw 6, and the guide portion 53 can reciprocate in the mounting cavity. ..

As shown in FIG. 17, the screw 6 is provided with a stop block 15, a stop cam is provided at the lower end of the nut 8, and the stop cam engages with the stop block 15 to limit the screw 6. , It is possible to prevent the preload spring 14 from being excessively compressed when the valve body is fully closed.

The screw 6 is provided with a screw portion, a smoothing guide portion, an injection molding joint portion, a positioning portion and a guide portion in this order, and a D port is provided on the side surface of the injection molding joint portion along the circumferential direction. An annular groove is provided, and the stop block 15 is injection molded into the screw 6 via an injection molding joint.

The limiter 13 and the spindle 26 are integrated by welding, and when the rotor assembly rotates counterclockwise, the rotor assembly is lifted upward by the screw transmission operation of the screw 6 and the nut 8 due to the valve opening operation, and the limiter The spindle 26 is also lifted upward by the 13 and separated from the valve opening.

As shown in FIG. 18, by installing a taper whose outer end surface has a tapered structure in the pilot spool 25, the pilot spool 25 spindles in the process of ventilation from the first connecting pipe 1 to the second connecting pipe 2. It is abutted and sealed with the first valve port 23 via the taper 54 under the guide of the gas, and the gas enters the second connecting pipe 2 after passing through the flow path hole 52, the cavity and the second valve port 51. Further, by adjusting the pitch between the taper of the spindle 26 and the second valve port 51, the position of the spindle 26 can be set by the coil as needed, and the spindle is raised or lowered depending on the screw transmission operation. In such an operating state, the pilot spool 25 is sealed by contacting the first valve port 23 due to its own weight and high pressure side pressure, and the flow rate is the second. It is possible to flow through only the valve port 51 of the above, and the spindle 26 realizes that the flow rate of the one-way connecting passage is controlled, thereby realizing the effect of controlling the flow rate in one direction.

As shown in FIG. 19, in the process of ventilation from the second connecting pipe 2 to the first connecting pipe 1, the spindle 26 is first opened, the pilot spool is pushed open by the action of the air flow, and the entire pilot spool 25 is opened. The taper 54 is separated from the first valve port 23, the second valve port and the taper 61 of the spindle 26 are in contact with each other and sealed, and the first valve port 23 and the first connecting pipe 1 are directly connected to each other. The airflow enters the first connecting pipe 1 from the second connecting pipe 2 and the first valve port 23, and at this time, it is not necessary to control the flow rate by the pilot spool 25.

The present invention is attached to a valve seat and a valve seat assembly that includes a valve seat, a first connecting pipe connected to one side of the valve seat, and a second connecting pipe connected to the bottom of the valve seat. A screw assembly including a screw and a spindle assembly including a spindle installed in the screw, and a valve communicating with a first connecting pipe and a second connecting pipe inside the valve seat assembly. A chamber is installed, a first valve port is provided at a place where the valve chamber and the second connecting pipe are communicated, and a pilot spool having a second valve port is installed in the valve chamber, and a pilot. The spool is mounted on the spindle and is guided by the spindle. In the first state, the spool guides the pilot spool to abut the first valve port, and the first connecting pipe is the second valve. The second valve port is conducted so as to be conducted to the second connecting pipe through the port, and in the second state, the spindle closes the second valve port and guides the pilot spool to the second valve port. An electronic expansion valve that separates from the valve port of 1 is provided, and the structure of the present invention realizes control of switching the flow rate of two flow paths by a pilot spool, and a check valve function without installing a plurality of expansion valves. By realizing the above, the control of the system is simplified, the use of parts is reduced, the assembly process is simplified, the number of steps is reduced, the manufacturing efficiency is improved, and the cost is reduced.

Further, in one embodiment of the electronic expansion valve further provided in the present invention, the nut 8 and / or the magnetic rotor 7 is provided with a limiting member for preventing the relative circumferential movement of the nut 8 and the screw 6. It is provided, and the blocking action of the limiting member can make it difficult to rotate the relative displacement between the nut 8 and the screw 6, improve the reliability of the operation of the electronic expansion valve, and position it during installation. By facilitating the process, the assembly process is simplified, the production efficiency is improved, and the production cost is reduced.

As shown with reference to FIGS. 5 and 6, specifically, the limiting member includes a stop cam 87 installed at the bottom of the outer periphery of the nut 8 and a cam 151 installed on the screw 7. The 151 is installed on the axial side surface of the stop block 15, and when the electronic expansion valve is fully closed, the cam 151 is brought into contact with the stop cam 87 to realize a stop action, and is generated between the nut 8 and the magnetic rotor 7. Limit the relative movement in the circumferential direction.

As mentioned above, the engagement of the first bonded surface and the second bonded surface facilitates the mounting and positioning of the nut and magnetic rotor, simplifying the assembly process, reducing the number of parts and reducing the process. Fewer, fewer quality control points, improved manufacturing efficiency and reduced costs. The blocking action of the limiting member can make the relative displacement rotation between the nut and the magnetic rotor difficult, improve the reliability of the operation of the electronic expansion valve, simplify the assembly process and improve the fabrication efficiency. Improve and reduce production costs.

The above are merely preferred embodiments of the present invention and are not intended to limit the present invention, and for those skilled in the art, the present invention can be modified and modified in various ways. Any modifications, equivalent replacements, improvements, etc. made within the scope of the gist and principle of the present invention are included in the scope of protection of the present invention.

Reference numerals in the figure: first connecting pipe 1, second connecting pipe 2, valve seat 3, spindle 4, sleeve holder 5, second valve port 51, flow path hole 52, guide portion 53, taper 54, valve. Chamber 55, screw 6, screw portion 61, smoothing guide portion 62, annular groove 63, injection molding joint portion 64, positioning portion 65, guide portion 66, D port 67, magnetic rotor 7, convex rib 71, groove 72, first 2 bonded surface 73, end surface 75, nut 8, enlarged portion 81, spindle guide portion 82, lock diameter portion 83, first bonded surface 84, rod-shaped protrusion 85, stepped surface 86, stop cam 87, preload spring mounting Part 88, female screw part 89, screw guide part 810, stop block 9, return spring 10, sleeve 11, stopper 12, disc-shaped part 121, outward warp member 122, gasket 13, preload spring 14, stop block, 15, cam , 151, first valve port 23, valve seat 24, pilot spool 25, spindle 26, spindle taper 261 and mounting cavity 91.

Claims (20)

With the screw assembly including the screw,
A nut fitted to the outside of the screw, a stopper installed on the upper outer ring of the nut, and a rotor assembly including a magnetic rotor fitted to the outer ring of the nut are included, and at least the outer peripheral wall of the nut includes at least. One first bonded surface is installed, and at least one second bonded surface that engages with and limits the first bonded surface is installed on the inner peripheral wall of the magnetic rotor. An electronic expansion valve in which the bonding surface of 1 and the surface of the second bonding surface are bonded together. The nut has an inner hole for mounting the screw, and the inner hole is provided with a screw guide portion, a female screw portion, a preload spring mounting portion, and a spindle guide portion in this order. The electronic expansion valve according to claim 1, wherein the inner diameter D1, the small diameter D2 of the female screw portion, the inner diameter D3 of the preload spring mounting portion, and the inner diameter D4 of the spindle guide portion satisfy D1> D2> D3> D4. The magnetic rotor is cylindrical, and the inner peripheral wall is provided with the same number of convex ribs as the number of the second bonded surfaces, and the second bonded surfaces are installed on the convex ribs. The electronic expansion valve according to claim 1. The first bonding surface is provided with rod-shaped protrusions along the vertical direction, and the second bonding surface is provided with grooves along the vertical direction, and the first bonding surface is provided. The electronic expansion valve according to claim 3, wherein the rod-shaped protrusion is accommodated in the groove when the surfaces of the second bonding surface are bonded to each other. The electronic expansion valve according to claim 2, wherein the bonding method of the first bonding surface and the second bonding adopts gap fitting, intermediate fitting, or tightening fitting. A lock diameter portion and an enlarged portion are provided at the tip of the nut, the stop block is locked in the lock diameter portion, and the diameter of the lock diameter portion is smaller than the diameter of the enlarged portion.
The stopper includes a disc-shaped portion and a warp member, and the warp member is fitted and fastened to the lock diameter portion, and the disc-shaped portion is brought into contact with the end face of the magnetic rotor. Item 1. The electronic expansion valve according to item 1. The electronic expansion valve according to claim 3, wherein the height of the convex rib is smaller than the height of the magnetic rotor. The screw is provided with a screw portion, a smoothing guide portion, an injection molding joint portion, a positioning portion and a guide portion in this order, and a D port is provided on the side surface of the injection molding joint portion along the circumferential direction. The electronic expansion valve according to claim 1, wherein an annular groove is provided. The electronic expansion valve according to claim 8, wherein the screw assembly further includes a stop block attached to the screw, and the stop block is injection-molded into the screw via an injection-molded joint. The convex ribs are four and are provided on the inner peripheral wall of the magnetic rotor at equal intervals, the first bonding surface is four, and the nuts are evenly distributed on the outer peripheral wall. The electronic expansion valve according to claim 2. The electronic expansion valve according to claim 1, wherein the nut and / or the screw is provided with a limiting member for preventing a relative movement of the nut and the screw in the circumferential direction. The limiting member includes a stop cam installed at the bottom of the outer circumference of the nut and a cam installed on the screw, and the cam is brought into contact with the stop cam when the electronic expansion valve is fully closed. The electronic expansion valve according to claim 11. The screw assembly further includes a stop block attached to the screw, the stop block is injection molded into the screw by the injection molding joint, and the cam is installed on the axial side surface of the stop block. The electronic expansion valve according to claim 12. The electronic expansion valve according to claim 13, wherein the warp member has at least two bent portions, and the bent portion clamps the lock diameter portion. A valve seat assembly including a valve seat for mounting the screw, a first connecting pipe connected to one side of the valve seat, and a second connecting pipe connected to the lower part of the valve seat.
Further including a spindle assembly including a spindle installed in the screw,
Inside the valve seat assembly, a valve chamber that communicates with the first connecting pipe and the second connecting pipe is installed, and at a location where the valve chamber and the second connecting pipe are communicated with each other. A first valve port is provided, and a pilot spool having a second valve port is installed in the valve chamber. The pilot spool is mounted on the spindle and uses the spindle as a guide. In the state of, the spindle guides the pilot spool to abut the first valve port, and the first connecting pipe is connected to the second connecting pipe via the second valve port. The second valve port is conducted so as to be conductive, and in the second state, the spindle closes the second valve port and guides the pilot spool from the first valve port. The electronic expansion valve according to claim 1, which is separated. The pilot spool is installed so as to surround one end of the pilot spool, is used for contacting the first valve port, and has a tapered outer end surface.
A guide portion installed at the other end of the pilot spool and fitted to the spindle to guide the spindle, and a first connecting pipe and a second valve port installed on the side wall of the pilot spool. The electronic expansion valve according to claim 15, further comprising at least one flow path hole for communication, and the second valve port and the flow path hole forming a connection passage. The electronic expansion valve according to claim 16, wherein the inner diameter of the valve chamber is larger than the inner diameter of the guide portion. The electronic expansion valve according to claim 16, wherein the flow path holes are four and are evenly distributed on the side wall of the pilot spool. The electronic expansion valve according to claim 16, wherein a spindle taper is provided at one end of the spindle so as to come into contact with the second valve port. The electronic expansion valve according to claim 16, wherein a spindle taper is provided at one end of the spindle so as to come into contact with the second valve port.

Images