CN112576762A

CN112576762A - Electric valve

Info

Publication number: CN112576762A
Application number: CN201910920623.3A
Authority: CN
Inventors: 不公告发明人
Original assignee: Hangzhou Sanhua Research Institute Co Ltd
Current assignee: Hangzhou Sanhua Research Institute Co Ltd
Priority date: 2019-09-27
Filing date: 2019-09-27
Publication date: 2021-03-30

Abstract

The utility model provides an electrically operated valve, including the valve part, valve body and first gland nut, the valve body has first step portion, the valve part includes sleeve pipe and connecting piece, the sleeve pipe includes the turn-ups, the connecting piece includes first flange portion, turn-ups and first flange portion butt, first flange portion and first step portion butt, sheathed tube radial periphery is located to first gland nut cover, first gland nut and turn-ups butt, first gland nut compresses tightly the turn-ups between first gland nut and first flange portion, like this, the sleeve pipe is fixed with the connecting piece assembly, compare in sleeve pipe and connecting piece welded fastening, one welding process has been reduced, the sheathed tube is connected.

Description

Electric valve

[ technical field ] A method for producing a semiconductor device

The invention relates to the technical field of fluid control components, in particular to an electric valve.

[ background of the invention ]

In an automobile air conditioning system, in order to improve the flow control precision of a working medium, an electric valve is often adopted as a throttling element, the inventor knows that the electric valve comprises a sleeve and a connecting piece, and the sleeve and the connecting piece are fixed by welding, so that the requirement on the material of the connecting piece is high, and how to improve the connection of the sleeve is a technical problem for the electric valve structure known by the inventor.

[ summary of the invention ]

The invention aims to provide an electric valve, which improves the connection problem of a sleeve.

In order to achieve the purpose, the invention adopts the following technical scheme:

the electric valve comprises a control part, a stator assembly, a valve part and a valve body, wherein the control part is connected with the stator assembly, the valve part is connected with the valve body, the stator assembly is positioned on the periphery of the valve part, the stator assembly is connected with the valve body, the valve body is provided with a first step part, the valve part comprises a sleeve and a connecting piece, the sleeve comprises a flanging, the connecting piece comprises a first flange part, the flanging is abutted to the first flange part, the first flange part is abutted to the first step part, the electric valve further comprises a first compression nut, the first compression nut is sleeved on the radial periphery of the sleeve, the first compression nut is abutted to the flanging, and the first compression nut compresses the flanging to enable the valve part to be limited with the valve body.

The invention provides an electric valve which comprises a valve component, a valve body and a first compression nut, wherein the valve body is provided with a first step part, the valve component comprises a sleeve and a connecting piece, the sleeve comprises a flanging, the connecting piece comprises a first flange part, the flanging is abutted against the first flange part, the first flange part is abutted against the first step part, the first compression nut is sleeved on the radial periphery of the sleeve and is abutted against the flanging, and the first compression nut compresses the flanging between the first compression nut and the first flange part.

[ description of the drawings ]

Figure 1 is a cross-sectional view of one embodiment of an electrically operated valve;

FIG. 2 is a cross-sectional view of the stator assembly and control housing of FIG. 1;

FIG. 3 is a schematic cross-sectional view of the cover plate of FIG. 1;

FIG. 4 is a cross-sectional structural view of the valve member of FIG. 1;

FIG. 5 is a cross-sectional structural view of the nut seat of FIG. 1;

FIG. 6 is a perspective view of the valve seat of FIG. 1;

FIG. 7 is a schematic cross-sectional view of the connector of FIG. 1;

FIG. 8 is a cross-sectional structural view of the valve body of FIG. 1;

figure 9 is an enlarged partial cross-sectional view of the electrically operated valve of figure 1;

figure 10 is a schematic cross-sectional view of a second embodiment of an electrically operated valve;

FIG. 11 is a cross-sectional view of the nut holder of FIG. 10 integrally injection molded with the attachment member;

figure 12 is an enlarged partial cross-sectional view of the electrically operated valve of figure 10;

figure 13 is a schematic cross-sectional view of a third embodiment of the electrically operated valve;

figure 14 is a cross-sectional view of the stator assembly and control housing of figure 13.

[ detailed description ] embodiments

The invention will be further described with reference to the following figures and specific examples:

referring to fig. 1, the electric valve 100 may be applied to an automotive air conditioning system, the electric valve 100 includes a control part 1, a stator assembly 2, a valve member 3 and a valve body 4, the control part 1 is connected with the stator assembly 2, the valve member 3 is connected with the valve body 4, the stator assembly 2 is located at the periphery of the valve member 3, the stator assembly 2 is connected with the valve body 4, and the electric valve is electrically connected and/or signal-connected with the outside through the control part 1.

Referring to fig. 1, the control portion 1 includes a circuit board 11, an outer housing 12 and a cover plate 13, the outer housing 12 and the cover plate 13 are respectively formed and fixedly connected in a sealing manner, in this embodiment, the outer housing 12 and the cover plate 13 are fixed by welding, specifically, referring to fig. 2 and 3, the outer housing 12 includes a first abutting portion 122 and a guide rib 123 protruding from the first abutting portion 122 in an axial direction, correspondingly, the cover plate 13 includes a second abutting portion 131 and a guide groove 132, the guide groove 132 is formed in a recessed manner in the axial direction of the cover plate 13, the guide groove 132 is positioned in cooperation with the guide rib 123, a height H of the guide rib 123 is set to be greater than a depth L of the guide groove 132 in the axial direction, so that when the outer housing 12 and the cover plate 13 are assembled, the guide rib 123 is inserted into the guide groove 132 to position the outer housing 12 and the cover plate 13, and then the guide rib 123 is partially, the first abutting portion 122 abuts against the second abutting portion 131 to fix the outer case 12 and the cover plate 13, but as another embodiment, the outer case 12 and the cover plate 13 may be fixed by potting. Referring to fig. 1, the outer housing 12 has a control chamber 121, and the circuit board 11 is located in the control chamber 121; the control part 1 further comprises an interface part 14, the control part 1 is electrically connected and/or signal connected with the outside through the interface part 14, the interface part 14 and the outer shell 12 are integrally formed by injection molding, the interface part 14 comprises a first pin 141, the interface part 14 is provided with a first accommodating cavity 142, the first pin 141 and the outer shell 12 are fixed by injection molding, specifically, the middle part of at least part of the first pin 141 and the outer shell 12 are fixed by injection molding, one end of the first pin 141 is located in the first accommodating cavity 142, the other end of the first pin 141 is located in the control cavity, and is spliced or welded with the circuit board 11 and can be electrically connected and/or signal connected with the circuit board 11.

Referring to fig. 1, the stator assembly 2 includes a cover 21, a coil winding 22 and a second pin 23, the cover 21 is formed by injection molding of the coil winding 22 and the second pin 23 as an injection insert, the cover 21 and the outer housing 12 are formed by injection molding, one end of the second pin 23 is located in the cover 21 and electrically connected and/or signal connected to the coil winding 22, and the other end of the second pin 23 is located outside the cover 21, specifically located in the control cavity 121, and electrically connected and/or signal connected to the circuit board 11 by plugging or welding. The electric valve 100 further comprises a pressure plate 5, the cross-sectional shape of the pressure plate 5 is substantially L-shaped, one part of the pressure plate 5 is fixedly connected with the stator assembly 2, specifically, the cover 21 in the stator assembly 2, and the other part of the pressure plate 5 is fixedly connected with the valve body 4 through screws, so as to fixedly connect the stator assembly 2 and the valve body 4. Referring to fig. 1 and 2, the stator assembly 2 has a first mounting portion 24, the first mounting portion 24 includes a cover portion and a coil winding portion exposed outside the cover 21, the cover portion is located at two ends of the first mounting portion 24, the first mounting portion 24 surrounds to form a first mounting cavity 25, the first mounting cavity 25 is in communication with the control cavity 121, a part of the valve member 3 is located in the first mounting cavity 25, a part of the valve member 3 is located in the control cavity 121, an end of the first mounting portion 24 close to the control cavity 121 is defined as an upper end, an end far from the control cavity 121 is defined as a lower end, an annular first sealing groove 241 is arranged at a position of the first mounting portion 24 close to the lower end, specifically, the first sealing groove 241 is arranged at a cover portion at a lower end of the first mounting portion 24, and the first sealing groove 241 is formed by inward recessing from a side wall of the first mounting portion 24.

Referring to fig. 4, the valve component 3 includes a valve core 31, a rotor assembly 32, a sleeve 33, a connecting member 34, a valve seat 35, a nut seat 36 and a lead screw 37, the connecting member 34 is fixedly connected with the nut seat 36, in this embodiment, the connecting member 34 is injection-molded with the nut seat 36, specifically, the connecting member 34 is an injection-molded insert, the nut seat 36 is integrally injection-molded, the nut seat 36 includes a connecting portion 362, at least a portion of the connecting portion 362 is injection-molded with the connecting member 34, and as another embodiment, the connecting member 34 and the nut seat 36 may also be fixed by fitting or welding. Referring to fig. 5, the nut seat 36 includes a first mounting hole 361 and a first cavity 363, the first mounting hole 361 is disposed to communicate with the first cavity 363, and an internal thread section is disposed on a portion of a sidewall of the first mounting hole 361. Referring to fig. 4, one end of the screw rod 37 is fixedly connected to the rotor assembly 32, the other end of the screw rod 37 passes through the first mounting hole 361 and the first cavity 363 and is connected to the valve core 31, and an external thread section matched with the internal thread section is arranged on the outer peripheral wall of the screw rod 37, so that when the stator assembly 2 generates an excitation magnetic field, the rotor assembly 32 drives the screw rod 37 to rotate together under the action of the excitation magnetic field, and meanwhile, the screw rod 37 and the nut seat 36 are in threaded fit and can drive the valve core 31 to reciprocate in the axial direction. The valve seat 35 is fixedly connected with the connecting member 34, but as another embodiment, the valve seat 35 and the connecting member 34 may also be integrally formed, in this embodiment, referring to fig. 4 and 6, the valve seat 35 includes an engaging portion 351 and a communicating portion 354, the communicating portion 354 is provided with at least one communicating through hole 3541, and the valve seat 35 is in interference fit with the connecting member 34 through the engaging portion 351, so as to fixedly connect the valve seat 35 and the connecting member 34. The valve seat 35 has a balance groove 352, a part of the balance groove 352 is located at the periphery of the matching portion 351, another part of the balance groove 352 is located at the periphery of the communicating portion 354, the balance groove 352 is formed by being recessed inward from the peripheries of the matching portion 351 and the communicating portion 354 along the radial direction of the valve seat 35, one end of the balance groove 352 located at the matching portion 351 is arranged flush with the free end of the matching portion 351 along the axial direction of the valve seat 35, the other end of the balance groove 352 is located at the communicating portion 354 and defines the axial direction of the valve seat 35 as the length direction, the length of the balance groove 352 is larger than that of the matching portion 351, the arrangement of the balance groove 352 is beneficial to balance the pressure of the working medium at the two ends of the valve core 31, specifically, referring to fig. 1, the electric valve 100 includes a second mounting cavity 45, the second mounting cavity 45 is arranged in communication with the valve seat 35 through a through hole 3541, the balance groove 352 is arranged to enable the working medium in the, therefore, the pressure of the working medium between the second mounting cavity 45 and the first cavity 363 is balanced, the influence of the pressure difference of the working medium at two ends of the valve core 31 on the movement of the valve core 31 is reduced, and the valve core 31 moves smoothly. Referring to fig. 4, the valve seat 35 further includes a valve port 353, a through hole 3541 is disposed in communication with the valve port 353, the working medium enters the valve port 353 through the through hole 3541, and the rotor assembly 33 drives the valve core 31 to pass through the valve core to be close to or far from the valve port 353, so that a flow cross-sectional area formed by the working medium at the valve port 353 is changed, and throttling is formed at the valve port 35; of course, as another embodiment, valve port 353 may be formed in valve body 4.

Referring to fig. 4 and 7, the sleeve 33 includes a flange 331, a body side wall 332, and a top 333, the flange 331 being located at one end of the body side wall 332, the top 333 being located at the other end of the body side wall 332, the sleeve 33 being integrally formed; the coupling member 34 includes a first flange portion 341 and a first side portion 342, and the first side portion 342 is provided with an annular second sealing groove 3420, the second sealing groove 3420 being formed by being depressed inward from an outer circumferential surface of the first side portion 342 in a radial direction of the first side portion 342. The partial body sidewall 332 is located at the radial outer periphery of the rotor assembly 32, the partial body sidewall 332 is located at the radial outer periphery of the first side portion 342, the turned-up edge 331 abuts against the first flange portion 341, specifically, the first flange portion 341 includes a first end face 3411 and a second end face 3412, and the turned-up edge 331 abuts against the first end face 3411.

Referring to fig. 8, the valve body 4 includes a first port 41, a second port 42, a second mounting portion 43 and a first channel 44, the second mounting portion 43 has a second mounting cavity 45, the first channel 44 communicates the first port 41 and the second port 42 through the second mounting cavity 45, wherein the first port 41 and the second port 42 are located on different sides of the valve body 4, an opening of the second mounting cavity 45 is located on another side of the valve body 4, and the three sides are different sides of the valve body 4, which is beneficial to avoiding interference and improving the utilization rate of the valve body 4. Of course, as another embodiment, the first port 41 and the second port 42 may be located on the same side of the valve body 4. In this embodiment, first passageway 44 includes first intercommunication section 441, the opening setting of second installation cavity 45 is kept away from to first port 41, first intercommunication section 441 is located between first port 41 and the second installation cavity 45, the one end and the first port 41 intercommunication of first intercommunication section 441, the other end and the second installation cavity 45 intercommunication of first intercommunication section 441, the central axis of first intercommunication section 441 and the central axis of second installation cavity 45 are the angle setting, be favorable to the miniaturization of valve body 4 like this.

Referring to fig. 1, at least a part of the valve member 3 is located in the second mounting cavity 45, and the valve member 3 is fixedly connected with the second mounting part 43, specifically, referring to fig. 8, the second mounting part 43 includes a second side part 431, a first step part 432 and a second step part 433, the second side part 431 is located closer to the opening of the second mounting cavity 45 than the first step part 432, the first step part 432 is located closer to the opening of the second mounting cavity 45 than the second step part 433, and the second side part 431 is formed with an internal thread. Referring to fig. 1, the electric valve 100 further includes a first compression nut 6, an outer peripheral surface of the first compression nut 6 is formed with an external thread that is engaged with the internal thread of the second side portion 431, the first compression nut 6 is fitted over a radial outer periphery of the main body side wall 332 of the sleeve 33, the first compression nut 6 is rotated to abut against the burring 331 of the sleeve 33, the burring 331 abuts against the first end face 3411 of the first flange portion 341, the second end face 3412 of the first flange portion 341 abuts against the first step portion 432, and thus, by rotating the first compression nut 6, the flange 331 is compressed between the first compression nut 6 and the first flange portion 341, the relative fixation of the sleeve 33 and the connecting piece 34 is ensured, at the same time, the first flange 341 is pressed between the first step 432 and the flange 331, and the relative fixation of the valve member 3 and the second mounting portion 43, that is, the relative fixation of the valve member 3 and the valve body 4 is ensured.

Referring to fig. 1 and 9, the electric valve 100 further includes a first sealing ring 7, a second sealing ring 8, and a third sealing ring 9, a portion of the first sealing ring 7 is located in the first sealing groove 241, a portion of the first sealing ring 7 abuts against an outer wall surface of the main body side wall 332 of the sleeve 33, the outer wall surface of the main body side wall 332 enables the first sealing ring 7 to be radially extruded and deformed, the first sealing ring 7 is provided to prevent moisture in the external environment from entering the control cavity 121 through a gap between an outer circumferential surface of the sleeve 33 and the stator assembly 3, so as to prevent the moisture in the external environment from contacting the circuit board 11, and the circuit board 11 is located in the control cavity 121 that is sealed and dried by welding the outer housing 12 and the cover plate 13, so that the risk that the circuit board 11 fails or is corroded due to contact with the moisture in the external environment can be effectively reduced. Part of the second seal ring 8 is located in the second seal groove 3420, part of the second seal ring 8 abuts against the inner wall surface of the main body side wall 332 of the sleeve 33, and the inner wall surface of the main body side wall 332 enables the second seal ring 8 to be radially extruded and deformed, so that the working medium in the sleeve 33 is prevented from leaking through a gap between the connecting piece 34 and the sleeve 33, the seal between the sleeve 33 and the connecting piece 34 is enhanced, the risk of leakage of the working medium is reduced, and the sealing performance of the valve component 3 is improved. The third seal ring 9 is disposed between the second step portion 433 and the second end face 3412 of the first flange portion 341, and by rotating the first compression nut 6, the second step portion 433 and the second end face 3412 compress the third seal ring 9 and generate axial deformation, and the provision of the third seal ring 9 is advantageous for enhancing the seal between the second mounting portion 43 and the valve member 3, and reducing the risk of leakage of the working medium to the outside of the valve body.

Referring to fig. 1, the sleeve 33 is arranged to effectively isolate the stator assembly 2 and the rotor assembly 32, so as to prevent the working medium in the sleeve 33 from leaking to the stator assembly 2, and since the electric valve is mostly applied to an air conditioning system, a certain pressure exists in the working medium such as a refrigerant, which puts forward a certain requirement on the strength of the sleeve 33, and at the same time, the excitation magnetic field generated by the stator assembly 2 needs to act on the rotor assembly 32, so that the material of the sleeve 33 needs to have a requirement on non-magnetic conductivity, so the sleeve 33 is generally made of a non-magnetic conductive metal material, in this embodiment, the sleeve 33 may be made of a stainless steel material, the sleeve 33 and the connecting piece 34 are assembled and fixed through the first gland nut 6, compared with the case that the sleeve 33 and the connecting piece 34 are welded and fixed, in order to facilitate welding, the general connecting piece 34 is also made of the same stainless, the connecting piece 34 can be made of other materials with lower price than stainless steel, which is beneficial to reducing the manufacturing cost of the connecting piece 34, namely the production cost of the electric valve 100, and simultaneously, one welding process is reduced, so that the assembly of the electric valve 100 is simple.

Referring to fig. 10 to 12, the technical solution of the second embodiment is mainly different from that of the first embodiment in that: in the second embodiment, the connecting member 34 and the nut seat 36 are integrally molded, the second sealing ring 8 is disposed between the first flange portion 341 and the flange 331, the sealing between the connecting seat 34 and the sleeve 33 is formed by the axial deformation of the second sealing ring 8, and the provision of the connecting member 34 and the nut seat 36 by integral injection molding is advantageous for reducing the manufacturing cost of the connecting member 34.

Specifically, the connecting member 34 and the nut seat 36 are formed by integral injection molding, the first end face 3411 of the first flange portion 341 is provided with an annular second sealing groove 3420 ', the second sealing groove 3420 ' is formed by being recessed from the first end face 3411 toward the inside of the first flange portion 341 in the axial direction of the first flange portion 341, a part of the second seal ring 8 is located in the second sealing groove 3420 ', a part of the second seal ring 8 abuts against the turned edge 331, and the turned edge 331 enables the axial direction of the second seal ring 8 to be pressed and deformed, thereby facilitating the sealing between the connecting seat 34 and the sleeve 33. Of course, it is conceivable that the second seal ring 8 may be provided between the first flange portion 341 and the bead 331 in the first embodiment; alternatively, in the second embodiment, the second seal ring 8 is provided in the same manner as in the first embodiment, that is, the second embodiment is mainly different from the first embodiment in that: in a second embodiment, the connection piece 34 is an integrally injection-molded piece with the nut seat 36.

Referring to fig. 13 to 14, the technical solution of the third embodiment is mainly different from that of the first embodiment in that: in the third embodiment, the first sealing groove 241' is provided near the upper end of the first mounting portion 24.

Specifically, the first sealing groove 241 'is provided at a cover portion of an upper end of the first mounting portion 24, and the first sealing groove 241' is formed to be recessed inward from a side wall of the first mounting portion 24 in a radial direction of the first mounting cavity 25. Part of the first sealing ring 7 is located in the first sealing groove 241', part of the first sealing ring 7 abuts against the outer wall surface of the main body side wall 332 of the sleeve 33, and the outer wall surface of the main body side wall 332 enables the first sealing ring 7 to be radially extruded and deformed, so that moisture in the external environment is prevented from entering the control cavity 121 through a gap between the outer peripheral surface of the sleeve 33 and the stator assembly 3, and contact between the moisture in the external environment and the circuit board 11 is also prevented.

It should be noted that: although the present invention has been described in detail with reference to the above-mentioned embodiments, it should be understood by those skilled in the art that the present invention may be modified and equivalents may be substituted for those skilled in the art, and all technical solutions and modifications that do not depart from the spirit and scope of the present invention should be covered by the claims of the present invention.

Claims

1. An electrically operated valve comprising a control part, a stator assembly, a valve member and a valve body, wherein the control part is connected with the stator assembly, the valve member is connected with the valve body, the stator assembly is positioned at the periphery of the valve member, the stator assembly is connected with the valve body, and the electrically operated valve is characterized in that: the valve body is provided with a first step portion, the valve component comprises a sleeve and a connecting piece, the sleeve comprises a flanging, the connecting piece comprises a first flange portion, the flanging is abutted against the first flange portion, the first flange portion is abutted against the first step portion, the electric valve further comprises a first compression nut, the first compression nut is sleeved on the radial periphery of the sleeve, the first compression nut is abutted against the flanging, and the first compression nut compresses the flanging to enable the valve component to be limited with the valve body.

2. Electrically operated valve according to claim 1, characterized in that: stator module includes first installation department, first installation department is located sheathed tube radial periphery, first installation department is provided with first sealed slot, the motorised valve still includes first sealing washer, part first sealing washer is located first sealed slot, part first sealing washer with sheathed tube outer wall butt, first sealing washer passes through first sealed slot with the sleeve pipe extrusion produces radial deformation.

3. Electrically operated valve according to claim 2, characterized in that: the connecting piece includes first lateral part, first lateral part is provided with the sealed slot of second, the sleeve pipe is located the radial periphery of first lateral part, motorised valve still includes the second sealing washer, and part the second sealing washer is located the sealed slot of second, and part the second sealing washer with the internal face butt of sleeve pipe, the second sealing washer passes through the sealed slot of second with the sleeve pipe extrusion produces radial deformation.

4. Electrically operated valve according to claim 2, characterized in that: the first flange portion is provided with a second sealing groove, the electric valve further comprises a second sealing ring, the second sealing ring is located between the second sealing groove and the flanging, part of the second sealing ring is located in the second sealing groove, part of the second sealing ring is abutted to the flanging, and the second sealing ring is axially deformed through the second sealing groove and the flanging.

5. Electrically operated valve according to any of claims 1-4, characterized in that: the valve component also comprises a nut seat, the nut seat comprises a connecting part, the connecting part is used as an injection insert, the nut seat is integrally formed by injection molding, and at least part of the connecting part and the connecting part are fixed by injection molding; or, the nut seat and the connecting piece are integrally formed by injection molding.

6. Electrically operated valve according to claim 5, characterized in that: the valve body comprises a first port, a second mounting portion and a first channel, the second mounting portion is provided with a second mounting cavity, part of the valve component is located in the second mounting cavity, the valve component is provided with a valve port, the first channel is communicated with the first port and the second port through the valve port, the first channel comprises a first communicating section, the first port is far away from an opening of the second mounting cavity, one end of the first communicating section is communicated with the first port, the other end of the first communicating section is communicated with the second mounting cavity, and a central line of the first communicating section and a central axis of the second mounting cavity are arranged at an angle.

7. Electrically operated valve according to claim 6, characterized in that: the second installation part comprises a second side part, the second side part is provided with an internal thread, the first compression nut is provided with an external thread, the first compression nut is in threaded fit with the second side part, the first compression nut compresses the flange between the first compression nut and the first flange part, and the first compression nut compresses the first flange between the flange and the first step part.

8. Electrically operated valve according to claim 7, characterized in that: the second mounting portion includes a second step portion, the electric valve further includes a third seal ring, the first gland nut compresses the third seal ring between the second step portion and the first flange portion, and the third seal ring is axially deformed by being pressed by the second step portion and the first flange portion.

9. Electrically operated valve according to any of claims 1-8, characterized in that: the valve component further comprises a valve seat, the valve seat comprises a matching portion and a communicating portion, the valve seat is provided with a balance groove, part of the balance groove is located at the periphery of the matching portion, the other part of the balance groove is located at the periphery of the communicating portion and is located in the radial direction of the valve seat, the balance groove is formed by inwards recessing the periphery of the matching portion and the periphery of the communicating portion, the balance groove is located in the axial direction of the valve seat, one end of the matching portion is flush with the free end of the matching portion, the other end of the balance groove is located in the communicating portion, the length of the balance groove is larger than that of the matching portion, and the valve seat is fixed with the connecting piece in an interference fit mode through the matching portion.