Electronic expansion valve capable of preventing impurity jam

Abstract

The present application relates to the technical field of electronic expansion valve, and particularly relates to an electronic expansion valve capable of preventing impurities from being stuck, which comprises a sleeve, a valve base assembly, a valve needle assembly, a nut assembly and a rotor assembly, the sleeve, the valve needle assembly and the nut assembly are all installed on the valve base assembly, the nut assembly is located in the interior of the sleeve, the valve needle assembly is located in the interior of the nut assembly, the rotor assembly is installed on the valve needle assembly, and the bottom of the inner wall of the sleeve is provided with a step; the sleeve seals the interiors of the valve needle assembly, the nut assembly, the rotor assembly and the valve base assembly, the valve needle assembly cooperates with the nut assembly and the rotor assembly to adjust the medium flow in the valve base assembly; the medium flows through the valve base assembly, then passes through the rotor assembly to provide power for the valve needle assembly, is guided by the nut assembly to the valve needle assembly, and moves upward or downward to adjust the flow in the valve base assembly, so that the convenience of the electronic expansion valve in flow control is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electronic expansion valves, and in particular to an electronic expansion valve capable of preventing impurities from causing the valve to jam. BACKGROUND

[0002] The heat exchange efficiency of a refrigerant system mainly depends on the pressure of the refrigerant at the high-pressure end and the outlet temperature of the cooling device in the system. The control of the refrigerant flow is usually determined according to the outlet temperature of the cooling device and the pressure. The flow control is relatively complex, and an electronic expansion valve is generally used to throttle and depressurize the refrigerant from the outlet of the cooling device. The flow of the refrigerant from the cooling device to the evaporating device is adjusted according to the temperature at the outlet of the evaporating device or other temperatures that need to be adjusted, so as to adapt to the changing needs of the refrigeration load.

[0003] However, the existing electronic expansion valves, such as the electronic expansion valve assembly, the electronic expansion valve and the refrigeration equipment disclosed in the patent application with the publication number CN117515193A and the electronic expansion valve disclosed in the patent application with the publication number CN108361393B, can all achieve flow adjustment.

[0004] However, it is found in use that most of the existing electronic expansion valves have a simple structure. Impurities in the medium can enter the electronic expansion valve due to the pressure difference, resulting in an increase in the operating resistance of the valve body and ultimately causing the valve to jam. A small number of electronic expansion valves, such as the electronic expansion valve disclosed in the utility model patent with the publication number CN207848582U, use a filter screen at the valve port to prevent impurities from entering the valve. However, this structure is inconvenient to install, and the presence of the filter screen increases the flow resistance in the system, resulting in poor practicability. Therefore, there is an urgent need for an electronic expansion valve capable of preventing impurities from causing the valve to jam to improve the above problems. SUMMARY

[0005] To solve the above technical problems, the present application provides an electronic expansion valve capable of preventing impurities from causing the valve to jam. Medium flows through a valve base assembly, and then a rotor assembly provides power to a valve needle assembly. The valve needle assembly is guided by a nut assembly, and moves upward or downward to adjust the flow in the valve base assembly, thereby improving the convenience of flow control of the electronic expansion valve.

[0006] The electronic expansion valve capable of preventing impurities from causing the valve to jam comprises a sleeve, a valve base assembly, a valve needle assembly, a nut assembly and a rotor assembly. The sleeve, the valve needle assembly and the nut assembly are all installed on the valve base assembly. The nut assembly is located inside the sleeve, and the valve needle assembly is located inside the nut assembly. The rotor assembly is installed on the valve needle assembly. A step is arranged at the bottom of the inner wall of the sleeve.

[0007] The sleeve seals the inside of the valve needle assembly, the nut assembly, the rotor assembly and the valve base assembly, and the valve needle assembly cooperates with the rotor assembly and the nut assembly to adjust the flow of the medium in the valve base assembly.

[0008] The medium flows through the valve base assembly, and then through the rotor assembly to drive the valve needle assembly, and through the nut assembly to guide the valve needle assembly to move up or down to adjust the flow in the valve base assembly, thereby improving the convenience of the electronic expansion valve in flow control.

[0009] Preferably, the valve base assembly comprises a valve seat and a valve base, the top of the valve base is interference fitted into the bottom of the valve seat, and the outer surface of the valve base is welded to the bottom of the valve seat, the upper part of the valve seat is provided with two groups of first square grooves, the lower part of the valve seat is provided with two groups of circular grooves and a first plane, the first plane is located at the top of the two groups of circular grooves, the inner wall of the valve base is provided with a plurality of waist-shaped grooves, the bottom of the valve base is provided with a plurality of flow-through holes, the number of the plurality of waist-shaped grooves is the same as that of the plurality of flow-through holes, and the plurality of waist-shaped grooves are respectively located directly above the plurality of flow-through holes; the medium passes through the flow-through holes on the valve base, is guided by the valve seat and the valve base, is driven by the magnetic rotor assembly to adjust the flow in the valve base, and passes through the flow-through holes on the valve base, and part of the medium passes through the first square grooves, the circular grooves and the space between the valve needle assembly and the valve base to enter the inside of the electronic expansion valve to adjust the pressure in the electronic expansion valve, thereby improving the convenience of the electronic expansion valve in flow adjustment and the convenience of the electronic expansion valve in internal pressure adjustment.

[0010] Preferably, the valve needle assembly comprises a screw rod, a valve needle sleeve, a valve needle, a valve needle spring, a bearing and a gasket, the valve needle is internally provided with a cavity, and the side end of the valve needle is provided with an opening, the top of the screw rod is inserted into the rotor assembly, the bottom of the screw rod is inserted into the cavity of the valve needle, the middle of the screw rod is screwed into the nut assembly, the valve needle sleeve is sleeved on the screw rod, the screw rod and the valve needle sleeve are in sliding connection, the bottom of the screw rod is larger in diameter than the inner ring of the valve needle sleeve, the bottom of the valve needle sleeve is inserted into the top of the valve needle in interference fit, and the outer surface of the valve needle sleeve is welded with the top end of the valve needle, the valve needle spring, the bearing and the gasket are all installed in the valve needle, and the gasket is below the bearing, the bottom end of the valve needle spring is in contact with the bearing, and the top end of the valve needle spring is in contact with the bottom end of the screw rod; the screw rod is driven to rotate by the rotor assembly, the screw rod is guided by the nut assembly, the valve needle is lowered, and the flow of the medium in the valve base is reduced, when the valve needle completely closes the valve base, the screw rod is rotated downward to press the valve needle spring, at the same time, the bearing ensures the axial fixation of the valve needle spring, and reduces the force when the screw rod rotates, and reduces the wear of each part, the pressure of the bearing on the valve needle is dispersed through the gasket, or the screw rod is driven to rotate in the opposite direction by the rotor assembly, and the bottom of the screw rod is limited by the valve needle sleeve, so that the valve needle rises, the flow of the medium in the valve base is increased, and in the process of adjusting the flow, part of the medium flows through the gap between the valve base and the valve needle into the inside of the electronic expansion valve, so that the pressure in the inside of the electronic expansion valve is balanced, when the particulate impurities enter the gap between the valve needle and the valve base, the valve needle sleeve and the screw rod rotate relatively during the upward movement of the valve needle, the radial rotation driving force on the valve needle becomes larger, the valve needle moves relatively, so that the particulate impurities enter the waist-shaped groove of the valve base, thereby improving the smoothness of the operation of the electronic expansion valve.

[0011] Preferably, the valve needle is provided with a flow guiding position, and the flow guiding position is higher than the lower surface of the waist-shaped groove; the particulate impurities are collected conveniently, and when the valve needle is closed, the gap between the flow guiding position on the valve needle and the valve base is smaller than the gap between the remaining positions on the valve needle and the valve base, so that the particulate impurities are prevented from entering the gap between the remaining positions on the valve needle and the valve base in the closed state, thereby improving the anti-impurity effect of the electronic expansion valve.

[0012] Preferably, the nut assembly comprises a nut, two sets of stop blocks, a spring guide rail and a sliding ring, the middle part of the screw rod is connected with the internal thread of the nut, the bottom of the nut is interference fitted on the top of the valve seat, a certain anti-disengagement force can be provided, and a second flat surface is arranged on the bottom of the nut, the edge of the second flat surface is treated with a parting process, which facilitates the demolding of the nut, the two sets of stop blocks are respectively located in the two sets of first square grooves of the valve seat, and the joint between the nut and the valve seat is welded, two sets of flow guide gaps one are left between the nut and the valve seat, and two flow guide gaps two are left between the nut and the valve base, which facilitates the upward flow of the medium, the spring guide rail and the sliding ring are sleeved on the nut, the bottom of the spring guide rail is clamped on the bottom of the nut, the top of the spring guide rail is provided with a first limiting end, the bottom of the nut is provided with a second limiting end, and one end of the sliding ring is interference fitted on the rotor assembly; by interference fitting the bottom of the nut on the top of the valve seat, a certain anti-disengagement force can be provided, without too much edge pressing, the axial force can be offset, the two sets of stop blocks are limited by the two sets of first square grooves on the valve seat respectively, which prevents the nut from rotating, when the rotor assembly drives the screw rod to rotate, the sliding ring rotates with the rotor assembly, and the spring guide rail guides the sliding ring, so that the sliding ring makes spiral ascending or descending action on the nut, when the sliding ring rises to the top of the nut, the sliding ring is blocked by the first limiting end on the spring guide rail, which limits the sliding ring from rising further, and in turn limits the rotor assembly from rotating further, when the sliding ring descends to the bottom of the nut, the sliding ring is blocked by the second limiting end on the nut, which limits the sliding ring from descending further, and in turn limits the rotor assembly from rotating further, and during the flow adjustment process, the medium flows through the circular groove on the valve seat, the first square groove on the valve seat, and is blocked by the stop block in turn, and due to the increase in space, the flow rate of the medium decreases, so that large particle impurities are left in the first square groove, the medium enters the flow guide gap one, and then the medium passes through the flow guide gap one and enters the upper part of the electronic expansion valve, a small part of the medium passes through the flow guide gap two and enters the upper part of the electronic expansion valve, thereby improving the precision of the electronic expansion valve in flow adjustment and the effect of preventing impurities from being stuck.

[0013] Preferably, the two sets of flow guide gaps one between the nut and the valve seat are distributed at ninety degrees with the two sets of first square grooves on the valve seat; the two sets of stop blocks facilitate the blocking of particle impurities in the medium, and improve the anti-impurity effect of the electronic expansion valve.

[0014] Preferably, the rotor assembly comprises a magnetic ring, a fixed plate and a stop ring, the top of the screw rod is inserted into the middle of the fixed plate, the magnetic ring is located in the sleeve, the fixed plate and the stop ring are both installed in the magnetic ring, and the magnetic ring, the fixed plate and the stop ring are connected together by injection molding, and a plurality of second square grooves are arranged on the inner wall of the stop ring; the one end of the slip ring is limited through the square groove on the inner wall of the stop ring, then when the stator drives the magnetic ring to rotate, the fixed plate drives the screw rod to rotate together, and the stop ring drives the slip ring to rotate together, so that the flow of the valve needle in the valve base is accurately adjusted, and in the process of flow adjustment, the medium flowing to the upper part of the electronic expansion valve enters the top of the electronic expansion valve through the gap between the magnetic ring and the sleeve, so that the smoothness of the operation of the electronic expansion valve is improved.

[0015] Preferably, the top of the fixed plate is provided with a plurality of third square grooves, the cross sections of the plurality of third square grooves are all right-angled trapezoids, and the right angle is located on the outer side of the third square groove; when the pressure in the electronic expansion valve decreases, the impurities in the middle and upper parts of the electronic expansion valve lose the upward power and fall on the first plane in the valve seat and the second plane of the nut bottom, the impurities at the top of the electronic expansion valve fall on the top end of the fixed plate, then with the rotation of the magnetic ring, the impurities at the top of the electronic expansion valve enter the plurality of third square grooves, and the right-angled sides of the third square grooves block the particulate impurities, so that the probability of the electronic expansion valve being stuck is reduced.

[0016] Preferably, the inner diameters of the two groups of circular grooves on the valve seat are greater than the gap between the valve needle and the valve seat; the gap between the nut and the valve seat is greater than the gap between the nut and the valve base; the width of the flow guiding gap between the nut and the valve seat is greater than the gap width between the magnetic ring and the sleeve; the gap between the remaining positions of the valve needle and the valve seat is greater than the gap between the flow guiding position on the valve needle and the valve seat; by limiting the sizes of the gaps, the large particulate impurities are separated from the medium, so that the electronic expansion valve is prevented from being stuck by the large particulate impurities, and the anti-stuck effect of the electronic expansion valve is improved.

[0017] Preferably, the bottom of the valve seat and the bottom of the valve base are both sleeved with O-shaped sealing rings; after the valve seat and the valve base are installed on the pipeline, the gaps between the valve seat and the valve base and the pipeline are sealed through the O-shaped sealing rings on the valve seat and the valve base, so that the sealing effect of the electronic expansion is improved.

[0018] Preferably, the bottom of the inner wall of the sleeve is provided with a step, the step is used as the pressing surface of the sleeve and the nut, so that the gap between the sleeve and the valve seat is left, and the gap width is less than 1 / 2 of the welding spot diameter.

[0019] Compared with the prior art, the present application has the following beneficial effects:

[0020] 1. The medium is guided by setting multiple groups of gaps and guide positions, the gap between the nut and the valve seat is larger than the gap between the nut and the valve base, the impurity medium containing large particles and the impurity medium containing small particles are separated, and the large particle impurities of the medium prevent the internal part of the electronic expansion valve from being stuck;

[0021] 2. The nut is limited by the stop block, the nut is prevented from rotating, and the medium is blocked by the stop block, most of the particle impurities are intercepted;

[0022] 3. The particle impurities are blocked by the third square groove on the fixed plate, and the convenience of collecting the particle impurities is improved;

[0023] 4. The gap between the valve needle and the valve seat is larger than the gap between the guide position on the valve needle and the valve seat, so that in the closed valve state, the impurities cannot enter the gap between the valve needle and the valve seat, and in the open valve state, the valve needle cannot be stuck. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 is a front view structure schematic diagram of the present application;

[0025] Figure 2 is a front view cross-sectional structure schematic diagram of the present application;

[0026] Figure 3 is a right view cross-sectional structure schematic diagram of the present application;

[0027] Figure 4 is an explosion structure schematic diagram of the present application;

[0028] Figure 5 is a front view cross-sectional enlarged structure schematic diagram of the rotor assembly of the present application;

[0029] Figure 6 is an axial enlarged structure schematic diagram of the rotor assembly of the present application;

[0030] Figure 7 is an axial enlarged structure schematic diagram of the nut assembly of the present application;

[0031] Figure 8 is a front view enlarged structure schematic diagram of the valve needle assembly of the present application;

[0032] Figure 9 is a front view cross-sectional enlarged structure schematic diagram of the valve needle assembly of the present application;

[0033] Figure 10 is a first axial enlarged structure schematic diagram of the valve seat of the present application;

[0034] Figure 11 is a second axial enlarged structure schematic diagram of the valve seat of the present application;

[0035] Figure 12 is a schematic view of the valve seat according to the present application in an enlarged cross-sectional view from the front;

[0036] Figure 13 is a schematic view of the valve base according to the present application in an enlarged view from the front;

[0037] Figure 14 is a schematic view of the valve base according to the present application in an enlarged cross-sectional view from the front;

[0038] Figure 15 is a schematic view of the nut and valve base according to the present application in an enlarged isometric view;

[0039] Figure 16 is a schematic view of the A portion according to the present application in an enlarged view; Figure 2

[0040] Figure 17 is a schematic view of the B portion according to the present application in an enlarged view; Figure 3

[0041] Figure 18 is a schematic view of the C portion according to the present application in an enlarged view; Figure 3

[0042] Figure 19 is a schematic view of the D portion according to the present application in an enlarged view. Figure 2 Reference signs in the drawing: 1 - sleeve, 2 - valve seat, 3 - valve base, 4 - first square recess, 5 - circular recess, 6 - waist-shaped recess, 7 - flow-through hole, 8 - screw, 9 - valve needle sleeve, 10 - valve needle, 11 - valve needle spring, 12 - bearing, 13 - gasket, 14 - flow guide position, 15 - nut, 16 - stop block, 17 - spring guide rail, 18 - sliding ring, 19 - flow guide gap 1, 20 - flow guide gap 2, 21 - magnetic ring, 22 - fixing plate, 23 - stop ring, 24 - third square recess, 25 - O-ring, 26 - welded joint of valve seat and valve base, 27 - welded joint of valve needle sleeve and valve needle, 28 - step.

[0043] DETAILED DESCRIPTION

[0044] For the purposes of facilitating the understanding of the present application, a more complete description of the present application will be provided below with reference to the relevant drawings. The present application can be realized in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided in order to make the disclosure of the present application more thorough and complete. EMBODIMENT

[0045] As Figures 1 to 19 ​​​​The utility model discloses an electronic expansion valve of preventing impurity jamming, including sleeve 1, still including valve base assembly, valve needle assembly, nut assembly and rotor assembly, sleeve 1, valve needle assembly and nut assembly are all installed on valve base assembly, and nut assembly is located inside sleeve 1, valve needle assembly is located inside nut assembly, rotor assembly is installed on valve needle assembly, the bottom of sleeve 1 inner wall is provided with step 28,

[0046] Sleeve 1 seals the inside of valve needle assembly, nut assembly, rotor assembly and valve base assembly, and valve needle assembly cooperates with nut assembly and rotor assembly to adjust the medium flow in valve base assembly,

[0047] Valve base assembly includes valve seat 2 and valve base 3, and the top of valve base 3 is inserted into the bottom of valve seat 2 with interference, and the outer surface of valve base 3 is welded with the bottom of valve seat 2, the upper portion in valve seat 2 is provided with two groups of first square grooves 4, the lower portion in valve seat 2 is provided with two groups of circular grooves 5 and first plane, and the first plane is located at the top of two groups of circular grooves 5, the inner wall of valve base 3 is provided with multiple groups of waist grooves 6, the bottom of valve base 3 is provided with multiple groups of flow-through holes 7, and the number of multiple groups of waist grooves 6 is same with that of multiple groups of flow-through holes 7, and multiple groups of waist grooves 6 are respectively located directly above multiple groups of flow-through holes 7,

[0048] Valve needle assembly includes screw rod 8, valve needle sleeve 9, valve needle 10, valve needle spring 11, bearing 12 and gasket 13, the inside of valve needle 10 is provided with cavity, and the side end of valve needle 10 is provided with opening, the top of screw rod 8 is inserted into rotor assembly, the bottom of screw rod 8 is inserted into the cavity of valve needle 10, the middle part of screw rod 8 is screwed into nut assembly, valve needle sleeve 9 is sleeved on screw rod 8, screw rod 8 is connected with valve needle sleeve 9 in sliding mode, the diameter of the bottom of screw rod 8 is greater than that of the inner ring of valve needle sleeve 9, the bottom of valve needle sleeve 9 is inserted into the top of valve needle 10 with interference, and the outer surface of valve needle sleeve 9 is welded with the top end of valve needle 10, valve needle spring 11, bearing 12 and gasket 13 are all installed in valve needle 10, and gasket 13 is located below bearing 12, the bottom end of valve needle spring 11 contacts with bearing 12, and the top end of valve needle spring 11 contacts with the bottom end of screw rod 8,

[0049] Valve needle 10 is provided with flow guide position 14, and flow guide position 14 is higher than the lower surface of waist groove 6,

[0050] The nut assembly comprises a nut 15, two groups of stop blocks 16, a spring guide rail 17 and a sliding ring 18, the middle part of the screw rod 8 is threadedly connected with the inner part of the nut 15, the bottom part of the nut 15 is interference-fitted on the top part of the valve seat 2, and a second plane is arranged on the bottom part of the nut 15, the edge of the second plane is subjected to a draft treatment, the nut is demolded, the two groups of stop blocks 16 are respectively located in the two groups of first square grooves 4 of the valve seat 2, and the joint between the nut 15 and the valve seat 2 is welded, two groups of flow guide gaps one 19 are left between the nut 15 and the valve seat 2, flow guide gaps two 20 are left between the nut 15 and the valve base 3, the medium flows upward, the spring guide rail 17 and the sliding ring 18 are sleeved on the nut 15, the bottom part of the spring guide rail 17 is clamped on the bottom part of the nut 15, the top part of the spring guide rail 17 is provided with a first limiting end, the bottom part of the nut 15 is provided with a second limiting end, and one end of the sliding ring 18 is interference-fitted on the rotor assembly;

[0051] The two groups of flow guide gaps one 19 between the nut 15 and the valve seat 2 are distributed at ninety degrees with the two groups of first square grooves 4 on the valve seat 2;

[0052] The rotor assembly comprises a magnetic ring 21, a fixed plate 22 and a stop ring 23, the top part of the screw rod 8 is interference-fitted on the middle part of the fixed plate 22, the magnetic ring 21 is located in the sleeve 1, the fixed plate 22 and the stop ring 23 are both installed in the magnetic ring 21, and the magnetic ring 21, the fixed plate 22 and the stop ring 23 are connected together in an injection molding manner, a plurality of second square grooves are arranged on the inner wall of the stop ring 23, and the size of the plurality of second square grooves on the stop ring 23 should be greater than [(sliding ring spacing - screw thread pitch) x stroke number of turns];

[0053] The top part of the fixed plate 22 is provided with a plurality of third square grooves 24, the cross sections of the plurality of third square grooves 24 are all right-angled trapezoids, and the right angle is located on the outer side of the third square groove 24;

[0054] The inner diameter of the two groups of circular grooves 5 on the valve seat 2 is greater than the gap between the valve needle 10 and the valve seat 2; the gap between the nut 15 and the valve seat 2 is greater than the gap between the nut 15 and the valve base 3; the width of the flow guide gap one 19 between the nut 15 and the valve seat 2 is greater than the gap width between the magnetic ring 21 and the sleeve 1; the gap between the valve needle 10 and the valve seat 2 at the remaining positions is greater than the gap between the flow guide position 14 on the valve needle 10 and the valve seat 2;

[0055] The bottom part of the valve seat 2 and the valve base 3 are both sleeved with an O-shaped sealing ring 25;

[0056] The bottom part of the inner wall of the sleeve 1 is provided with a step 28, the step 28 is used as a pressing surface of the sleeve 1 and the nut 15, a gap is left between the sleeve 1 and the valve seat 2, and the gap width is less than 1 / 2 of the welding light spot diameter;

[0057] After the valve seat 2 and the valve bottom 3 are installed on the pipeline, the gap between the valve seat 2 and the valve bottom 3 and the pipeline is sealed by the O-shaped sealing ring 25 on the valve seat 2 and the valve bottom 3, and then the flow in the valve bottom 3 is adjusted, the stator driving magnetic ring 21 is rotated, the fixed plate 22 drives the screw rod 8 to rotate, the stop ring 23 drives the sliding ring 18 to rotate, the screw rod 8 is guided by the nut assembly, the screw rod 8 is pressed downward to extrude the valve needle spring 11, the bearing 12 ensures the axial fixation of the valve needle spring 11, reduces the force when the screw rod 8 rotates, reduces the wear of each part, the pressure of the bearing 12 on the valve needle 10 is dispersed by the gasket 13, the valve needle 10 is lowered, the flow of the medium in the valve bottom 3 is reduced, or the screw rod 8 is driven to rotate in the opposite direction by the rotor assembly, the bottom of the screw rod 8 is limited by the valve needle sleeve 9, the valve needle 10 is raised, the flow of the medium in the valve bottom 3 is increased, and in the process of adjusting the flow, the sliding ring 18 rotates with the rotor assembly, the sliding ring 18 is guided by the spring guide rail 17, the sliding ring 18 makes spiral upward or downward movement on the nut 15, when the sliding ring 18 rises to the top of the nut 15, the valve port is opened to the maximum, which is 100, the sliding ring 18 is blocked by the first limiting end on the spring guide rail 17, the sliding ring 18 is limited to continue to rise, and the rotor assembly is limited to continue to rotate, when the sliding ring 18 falls to the bottom of the nut 15, the sliding ring 18 is blocked by the second limiting end on the nut 15, the valve port is closed at this time, which is 0, the sliding ring 18 is limited to continue to fall, and the rotor assembly is limited to continue to rotate, and in the process of adjusting the flow, because the inner diameter of the two groups of circular grooves 5 on the valve bottom 3 is larger than the gap between the valve needle 10 and the valve seat 2, the medium containing large particle impurities enters the first square groove 4 of the valve seat 2 through the circular groove 5 on the valve seat 2, is blocked by the stop block 16, and because the space is enlarged, the flow rate of the medium is reduced, the large particle impurities are left in the first square groove 4, the medium enters the flow guiding gap one 19, then the medium passes through the flow guiding gap one 19 and enters the upper part of the electronic expansion valve, a small part of the medium passes through the flow guiding gap two 20 and enters the upper part of the electronic expansion valve, and part of the medium does not contain large particles, part of the medium flows through the gap between the valve bottom 3 and the valve needle 10 and enters the inside of the electronic expansion valve, when the particle impurities enter the gap between the valve needle 10 and the valve bottom 3 and cause the valve needle 10 to be stuck, the valve needle sleeve 9 and the screw rod 8 rotate relatively during the upward movement of the valve needle, the radial rotary driving force on the valve needle 10 becomes larger, the valve needle 10 moves relatively, the particle impurities enter the waist-shaped groove 6 in the valve bottom 3, then the medium in the upper part of the electronic expansion valve passes through the gap between the magnetic ring 21 and the sleeve 1 and enters the top of the electronic expansion, balances the pressure in the electronic expansion valve, when the pressure in the electronic expansion valve becomes smaller, the impurities in the middle and upper parts of the electronic expansion valve lose the upward power and fall on the first plane in the valve seat 2 and the second plane at the bottom of the nut 15, the impurities in the top of the electronic expansion valve fall on the top end of the fixed plate 22, then with the rotation of the magnetic ring 21,The impurities on the top of the electronic expansion valve enter the third group of rectangular grooves 24 at most, and the right-angle sides of the third group of rectangular grooves 24 block the large-particle impurities, so that the large-particle impurities are prevented from entering the small-gap position, and the electronic expansion valve is prevented from being stuck.

[0058] Because When the inlet pressure P1 and the inlet flow Q of the 03 flow passage are constant, the larger the S is, the smaller the v in the direction is, and according to the Bernoulli equation, When the v 2 decreases, the P 2 in the direction increases, the pressure difference △P with the inlet pressure P 1 decreases, the force generated by the fluid in the direction decreases, the large-particle impurities are not easy to pass through the large-flow-area position, the larger pressure difference force makes the impurities stay near the small-flow-area position, so that the impurities in the large-flow-hole position are prevented from accumulating to cause the function of the balanced flow passage to fail; Q: inlet flow, S: cross-sectional area, v: flow rate.

[0059] The electronic expansion valve for preventing impurities from being stuck of the present application is implemented in a common mechanical manner, as long as the beneficial effects can be achieved; the O-shaped sealing ring 25 of the electronic expansion valve for preventing impurities from being stuck of the present application is purchased on the market, and the technical personnel in the industry only need to install and operate according to the attached instruction manual, without the technical personnel in the field having to pay creative labor.

[0060] The above is only the preferred embodiment of the present application, and it should be pointed out that for ordinary technical personnel in the technical field, several improvements and modifications can be made without departing from the technical principles of the present application, and these improvements and modifications should be regarded as the protection scope of the present application.

Claims

1. An electronic expansion valve against foreign matter seizure, comprising a sleeve (1); characterized in that, Also include valve seat assembly, valve needle assembly, nut assembly and rotor assembly, sleeve (1), valve needle assembly and nut assembly are installed on the valve seat assembly, and the nut assembly is located inside the sleeve (1), the valve needle assembly is located inside the nut assembly, the rotor assembly is installed on the valve needle assembly, the bottom of the inner wall of the sleeve (1) is provided with a step (28); The sleeve (1) seals the inside of the valve needle assembly, the nut assembly, the rotor assembly and the valve seat assembly, and the valve needle assembly cooperates with the rotor assembly and the nut assembly to adjust the medium flow in the valve seat assembly; The valve seat assembly includes a valve seat (2) and a valve base (3), the top of the valve base (3) is inserted into the bottom of the valve seat (2) with interference, and the outer surface of the valve base (3) is welded with the bottom of the valve seat (2), the upper part of the valve seat (2) is provided with two groups of first square grooves (4), the lower part of the valve seat (2) is provided with two groups of circular grooves (5) and a first plane, the first plane is located at the top of the two groups of circular grooves (5), the inner wall of the valve base (3) is provided with a plurality of waist type grooves (6), the bottom of the valve base (3) is provided with a plurality of flow holes (7), and the number of the plurality of waist type grooves (6) is the same as that of the plurality of flow holes (7), and the plurality of waist type grooves (6) are located directly above the plurality of flow holes (7) respectively; The valve needle assembly includes a screw rod (8), a valve needle sleeve (9), a valve needle (10), a valve needle spring (11), a bearing (12) and a gasket (13), the inside of the valve needle (10) is provided with a cavity, and the side end of the valve needle (10) is provided with an opening, the top of the screw rod (8) is inserted into the rotor assembly, the bottom end of the screw rod (8) is inserted into the cavity of the valve needle (10), the middle part of the screw rod (8) is threadedly installed in the nut assembly, the valve needle sleeve (9) is sleeved on the screw rod (8), the screw rod (8) and the valve needle sleeve (9) are in sliding connection, the diameter of the bottom of the screw rod (8) is greater than that of the inner ring of the valve needle sleeve (9), the bottom of the valve needle sleeve (9) is inserted into the top of the valve needle (10) with interference, and the outer surface of the valve needle sleeve (9) is welded with the top end of the valve needle (10), the valve needle spring (11), the bearing (12) and the gasket (13) are installed in the valve needle (10), and the gasket (13) is located below the bearing (12), the bottom end of the valve needle spring (11) contacts the bearing (12), and the top end of the valve needle spring (11) contacts the bottom end of the screw rod (8). The nut assembly comprises a nut (15), two groups of stop blocks (16), a spring guide rail (17) and a sliding ring (18), the middle part of the screw rod (8) is threadedly connected with the inner part of the nut (15), the bottom part of the nut (15) is inserted into the top part of the valve seat (2) in an interference fit, a second plane is arranged on the bottom part of the nut (15), the edge of the second plane is subjected to a draft treatment, the two groups of stop blocks (16) are respectively arranged in the two groups of first square grooves (4) of the valve seat (2), the joint between the nut (15) and the valve seat (2) is welded, two groups of flow guide gaps (19) are left between the nut (15) and the valve seat (2), a flow guide gap (20) is left between the nut (15) and the valve base (3), so that the medium can flow upward, the spring guide rail (17) and the sliding ring (18) are both sleeved on the nut (15), the bottom part of the spring guide rail (17) is clamped on the bottom part of the nut (15), the top part of the spring guide rail (17) is provided with a first limiting end, the bottom part of the nut (15) is provided with a second limiting end, and one end of the sliding ring (18) is inserted into the rotor assembly.

2. The electronic expansion valve according to claim 1, wherein The valve needle (10) is provided with a flow guide position (14), and the flow guide position (14) is higher than the lower surface of the waist-shaped groove (6).

3. The electronic expansion valve according to claim 1, wherein The two groups of flow guide gaps (19) between the nut (15) and the valve seat (2) are distributed at an angle of 90 degrees with the two groups of first square grooves (4) on the valve seat (2).

4. The electronic expansion valve according to claim 1, wherein The rotor assembly comprises a magnetic ring (21), a fixed plate (22) and a stop ring (23), the top part of the screw rod (8) is inserted into the middle part of the fixed plate (22), the magnetic ring (21) is arranged in the sleeve (1), the fixed plate (22) and the stop ring (23) are both arranged in the magnetic ring (21), and the magnetic ring (21), the fixed plate (22) and the stop ring (23) are connected together in an injection molding manner, and a plurality of second square grooves are arranged on the inner wall of the stop ring (23).

5. The electronic expansion valve according to claim 4, wherein The top part of the fixed plate (22) is provided with a plurality of third square grooves (24), the cross sections of the plurality of third square grooves (24) are all right-angled trapezoids, and the right angle is located on the outer side of the third square groove (24).

6. The electronic expansion valve according to claim 4, wherein The inner diameters of the two groups of circular grooves (5) on the valve seat (2) are greater than the gap between the valve needle (10) and the valve seat (2); the gap between the nut (15) and the valve seat (2) is greater than the gap between the nut (15) and the valve base (3); the width of the flow guide gap (19) between the nut (15) and the valve seat (2) is greater than the gap width between the magnetic ring (21) and the sleeve (1); the gap between the valve needle (10) and the valve seat (2) at other positions is greater than the gap between the flow guide position (14) on the valve needle (10) and the valve seat (2).

7. The electronic expansion valve according to claim 1, wherein The bottom parts of the valve seat (2) and the valve base (3) are both sleeved with O-shaped sealing rings (25).

Images