CN112620887A - Subway door framework welding process - Google Patents
Subway door framework welding process Download PDFInfo
- Publication number
- CN112620887A CN112620887A CN202011573886.0A CN202011573886A CN112620887A CN 112620887 A CN112620887 A CN 112620887A CN 202011573886 A CN202011573886 A CN 202011573886A CN 112620887 A CN112620887 A CN 112620887A
- Authority
- CN
- China
- Prior art keywords
- welding
- frame
- reinforcing rib
- workpiece
- subway door
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K9/00—Arc welding or cutting
- B23K9/16—Arc welding or cutting making use of shielding gas
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K9/00—Arc welding or cutting
- B23K9/0026—Arc welding or cutting specially adapted for particular articles or work
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K9/00—Arc welding or cutting
- B23K9/235—Preliminary treatment
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Plasma & Fusion (AREA)
- Mechanical Engineering (AREA)
- Butt Welding And Welding Of Specific Article (AREA)
Abstract
The invention discloses a subway door frame welding process, the subway door frame comprises a frame, a window frame, reinforcing ribs and a middle bent beam, the frame comprises an upper frame, a lower frame, a left frame and a right frame, the reinforcing ribs comprise a reinforcing rib I, a reinforcing rib II and a reinforcing rib III, the welding is performed by adopting alternating current pulse argon arc welding, the argon purity is 99.90 percent, the aperture of a nozzle selected by the alternating current pulse argon arc welding is 13mm, the argon flow is 8-10 L.min, the distance between the nozzle and a workpiece is 8-12mm, the frame welding, the reinforcing ribs welding, the middle bent beam welding and the window frame welding are sequentially performed in a forward mounting mode, the subway door frame is reversely mounted and welded according to the sequence and welding parameters of the forward mounting welding after the forward mounting welding is completed, the deformation of a welding piece is reduced by adopting a method for controlling the temperature of the welding piece, the reasonable welding sequence is matched, the deformation of the subway door frame, the welding quality is good.
Description
Technical Field
The invention relates to the technical field of metro door framework welding, in particular to a metro door framework welding process.
Background
The subway is a rapid, large-traffic and electric traction rail transit built in cities, a subway door framework adopts a thin aluminum alloy section, the aluminum alloy section has good casting performance and plastic processing performance, and also has good electric conduction, heat conduction, corrosion resistance and weldability, and the problems of large welding deformation, poor welding quality and the like of the subway door framework exist in the existing welding processing process of the subway framework.
Disclosure of Invention
The invention aims to overcome the defects in the prior art, provides the welding process of the metro door framework, has small welding deformation of the metro door framework and good welding quality, and can effectively solve the problems in the background technology.
In order to achieve the purpose, the invention provides the following technical scheme: the utility model provides a subway door skeleton welding process, subway door skeleton include frame, window frame, strengthening rib and middle camber beam, the frame includes frame, lower frame, left frame and right frame, the strengthening rib includes strengthening rib one, strengthening rib two and strengthening rib three, adopts the pulse argon arc welding of exchanging to weld, and argon gas purity 99.90%, concrete welding step is as follows:
A. frame welding: fixing an upper frame, a lower frame, a left frame and a right frame on a clamp, welding current of 160-180A, welding voltage of 18-20V and welding speed of 2-2.5mm & s, firstly welding the upper frame and the left frame, secondly welding the lower frame and the right frame, then welding the upper frame and the right frame, and finally welding the lower frame and the left frame;
B. welding the reinforcing ribs: fixing a first reinforcing rib between a left frame and a right frame through a clamp, welding current of 160-180A, welding voltage of 18-20V and welding speed of 2-2.5 mm.s, firstly, respectively welding the left end and the right end of the first reinforcing rib with the left frame and the right frame, fixing a third reinforcing rib between the first reinforcing rib and the lower frame through the clamp, respectively welding the top end and the tail end of the third reinforcing rib with the first reinforcing rib and the right frame, fixing a second reinforcing rib between the left frame and the right frame through the clamp, positioning the two reinforcing ribs at the upper end of the third reinforcing rib, welding current of 140-170A, welding voltage of 16-18V and welding speed of 1.5-2 mm.s, welding a second reinforcing rib at the upper end of the third reinforcing rib, after welding, welding current of 160-180A, welding voltage of 18-20V and welding speed of 2-2.5 mm.s, welding two ends of the second reinforcing rib with the left frame and the right frame respectively;
C. welding a middle bent beam: fixing the middle bent beam between the left frame and the right frame through a clamp, wherein the middle bent beam is positioned at the upper end of the third reinforcing rib, welding current is 140-170A, welding voltage is 16-18V, welding speed is 1.5-2mm · s, and two ends of the middle bent beam are respectively welded with the left frame and the right frame;
D. welding a window frame: fixing the window frame among the left frame, the right frame and the upper frame through a clamp, welding current 160-180A, welding voltage 18-20V, welding speed 2-2.5mm & s, wherein the left end and the right end of the top end of the window frame are provided with two welding points, one corner of the top end of the window frame is welded with the upper frame, the other corner of the top end of the window frame is welded with the upper frame, the left side wall and the right side wall of the window frame are symmetrically provided with six welding points, the left side wall and the right side wall of the window frame are sequentially subjected to left-right diagonal electric welding, the left end and the right end of the bottom end of the window frame are provided with two welding points, one corner of the bottom end of the window frame is welded with a reinforcing rib I, and the;
E. and (4) reversely installing the metro door framework, and reversely installing and welding the metro door framework according to the sequence of the normal installation welding and the welding parameters.
Furthermore, the diameter of a nozzle used for alternating current pulse argon arc welding is 13mm, the argon flow is 8-10 L.min, and the distance between the nozzle and the workpiece is 8-12 mm.
Further, the workpiece is subjected to surface treatment before welding in the steps A, B, C, D and E, the surface of the workpiece is wiped by acetone, and then metal is directly ground by a copper wire brush with the diameter of 0.16-0.18 mm.
Further, the surface treatment is carried out on the workpiece before welding in the step A, the step B, the step C, the step D and the step E, and the preheating treatment is carried out on the metro door framework workpiece before welding, wherein the preheating temperature is 80-120 ℃.
Further, after the welding in the steps A, B, C, D and E, the surface of the welding position of the workpiece is treated, and the welding position is polished by using a copper wire brush with the diameter of 0.16-0.18 mm.
Further, during welding in the steps A, B, C, D and E, measuring the temperature of the welded workpiece by an infrared temperature measuring instrument, stopping welding when the temperature of the welded workpiece exceeds 80 ℃, and continuing welding after the temperature of the welded workpiece is reduced.
Compared with the prior art, the invention has the beneficial effects that: local iron gate skeleton welding process wipes the stain of getting rid of workpiece surface through acetone to workpiece surface, polish the work piece through the steel brush, brush until brushing the work piece and spill metallic luster, remove the oxide film, preheat and to make the weldment reduce the deformation, reduce defects such as gas pocket, special cooperation through nozzle aperture and argon gas flow makes the gas protection effect best, effective guard space is the biggest, the deflection of weldment has been reduced through the method that adopts control weldment temperature, cooperate reasonable welding order, the deformation of iron gate skeleton is little, welding quality is good.
Drawings
FIG. 1 is a schematic structural diagram of a metro door framework of the present invention;
in the figure: 11 upper frame, 12 lower frame, 21 left frame, 22 right frame, 3 window frames, 4 reinforcing ribs I, 5 reinforcing ribs II, 6 reinforcing ribs III and 7 middle camber beam.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example one
Referring to fig. 1, the present invention provides a technical solution: the utility model provides a subway door skeleton welding process, subway door skeleton include frame, window frame, strengthening rib and middle camber beam 7, the frame includes frame 11, lower frame 12, left side frame 21 and right frame 22, the strengthening rib includes strengthening rib one 4, two 5 and three 6 of strengthening rib, adopts the welding of alternating current pulse argon arc welding, and argon gas purity 99.90%, the nozzle aperture that alternating current pulse argon arc welding chooseed for use is 13mm, and the argon gas flow is 8-10 L.min, and the distance of nozzle and work piece is 8-12mm, and concrete welding step is as follows:
A. frame welding: wiping the surfaces of the upper frame 11, the lower frame 12, the left frame 21 and the right frame 22 by using acetone to remove stains on the surfaces of workpieces, polishing the upper frame 11, the lower frame 12, the left frame 21 and the right frame 22 by using copper wire brushes with the diameters of 0.16-0.18mm, preheating the upper frame 11, the lower frame 12, the left frame 21 and the right frame 22 after polishing, fixing the upper frame 11, the lower frame 12, the left frame 21 and the right frame 22 on a clamp, welding current of 180A, welding voltage of 18-20V and welding speed of 2-2.5mm & s, firstly welding the upper frame 11 and the left frame 21, secondly welding the lower frame 12 and the right frame 22, secondly welding the upper frame 12 and the right frame 21, and finally welding the lower frame 12 and the left frame 11, measuring the temperature of the workpieces when being welded by an infrared thermometer, stopping welding when the temperature of the welded workpieces exceeds 80 ℃, continuing welding after the temperature of the weldment is reduced to room temperature, and polishing the welding positions of the upper frame 11, the lower frame 12, the left frame 21 and the right frame 22 by using a copper wire brush with the diameter of 0.16-0.18mm after the welding is finished;
B. welding the reinforcing ribs: wiping the surfaces of the first reinforcing rib 4, the second reinforcing rib 5 and the third reinforcing rib 6 by using acetone to remove stains on the surfaces of workpieces, polishing the first reinforcing rib 4, the second reinforcing rib 5 and the third reinforcing rib 6 by using a copper wire brush with the diameter of 0.16-0.18mm, preheating the first reinforcing rib 4, the second reinforcing rib 5 and the third reinforcing rib 6 after polishing, fixing the first reinforcing rib 4 between the left frame 21 and the right frame 22 through a clamp, welding current 160 and 180A, welding voltage 18-20V and welding speed 2-2.5mm & s, firstly welding the left end and the right end of the first reinforcing rib 4 with the left frame 21 and the right frame 22 respectively, fixing the third reinforcing rib 6 between the first reinforcing rib 4 and the lower frame 12 through the clamp, welding the top end and the tail end of the third reinforcing rib 6 with the first reinforcing rib 4 and the right frame 12 respectively, fixing the second reinforcing rib 5 between the left frame 21 and the right frame 22 through the clamp, the second reinforcing rib 5 is positioned at the upper end of the third reinforcing rib 6, welding current is 140-170A, welding voltage is 16-18V, welding speed is 1.5-2 mm.s, the second reinforcing rib 5 is welded at the upper end of the third reinforcing rib 6, after welding is finished, welding current is 160-180A, welding voltage is 18-20V, welding speed is 2-2.5 mm.s, two ends of the second reinforcing rib 5 are respectively welded with the left frame 21 and the right frame 22, temperature measurement is carried out on a workpiece during welding through an infrared thermometer, welding is stopped when the temperature of the workpiece exceeds 80 ℃, welding is continued after the temperature of the workpiece is reduced to room temperature, and the welding positions of the first reinforcing rib 4, the second reinforcing rib 5 and the third reinforcing rib 6 are ground by using a copper wire brush with the diameter of 0.16-0.18mm after welding is finished;
C. welding the middle bent beam 7: wiping the surface of the middle camber beam 7 by using acetone to remove stains on the surface of a workpiece, polishing the middle camber beam 7 by using a copper wire brush with the diameter of 0.16-0.18mm, preheating the middle camber beam 7 after polishing, fixing the middle camber beam 7 between the left frame 21 and the right frame 22 by using a clamp, wherein the middle camber beam 7 is positioned at the upper end of the three reinforcing ribs 6, welding current is 140-;
D. welding a window frame 3: wiping the surface of a window frame 3 by using acetone to remove stains on the surface of a workpiece, polishing the window frame 3 by using a copper wire brush with the diameter of 0.16-0.18mm, preheating the window frame 3 after polishing, fixing the window frame 3 between a left frame 21, a right frame 22 and an upper frame 11 by using a clamp, welding current of 160-180A, welding voltage of 18-20V, welding speed of 2-2.5 mm.s, arranging two welding points at the left end and the right end of the top end of the window frame 3, welding one corner of the top end of the window frame 3 with the upper frame 11, welding the other corner of the top end of the window frame 3 with the upper frame 11, symmetrically dividing the left side wall and the right side wall of the window frame 3 into six welding points, sequentially carrying out left-right diagonal electric welding on the left side wall and the right side wall of the window frame 3, the left end and the right end of the bottom end of the window frame 3, welding one corner of the bottom end of the window, welding the other corner of the bottom end of the window frame 3 and the reinforcing rib I4 together, measuring the temperature of a workpiece during welding by an infrared thermometer in the welding process, stopping welding when the temperature of the weldment exceeds 80 ℃, continuing welding after the temperature of the weldment is reduced to room temperature, and polishing the welding position of the window frame 3 by using a copper wire brush with the diameter of 0.16-0.18mm after welding is finished;
E. and (4) reversely assembling the metro door framework, and reversely assembling and welding the metro door framework according to the sequence, the method and the welding parameters of the forward assembling and welding.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (6)
1. The subway door framework welding process is characterized by comprising the following steps of: subway door skeleton includes frame, window frame, strengthening rib and middle camber beam, the frame includes frame, lower frame, left side frame and right frame, the strengthening rib includes strengthening rib one, strengthening rib two and strengthening rib three, adopts to exchange pulse argon arc to weld, and argon gas purity 99.90%, concrete welding step is as follows:
A. frame welding: fixing an upper frame, a lower frame, a left frame and a right frame on a clamp, welding current of 160-180A, welding voltage of 18-20V and welding speed of 2-2.5mm & s, firstly welding the upper frame and the left frame, secondly welding the lower frame and the right frame, then welding the upper frame and the right frame, and finally welding the lower frame and the left frame;
B. welding the reinforcing ribs: fixing a first reinforcing rib between a left frame and a right frame through a clamp, welding current of 160-180A, welding voltage of 18-20V and welding speed of 2-2.5 mm.s, firstly, respectively welding the left end and the right end of the first reinforcing rib with the left frame and the right frame, fixing a third reinforcing rib between the first reinforcing rib and the lower frame through the clamp, respectively welding the top end and the tail end of the third reinforcing rib with the first reinforcing rib and the right frame, fixing a second reinforcing rib between the left frame and the right frame through the clamp, positioning the two reinforcing ribs at the upper end of the third reinforcing rib, welding current of 140-170A, welding voltage of 16-18V and welding speed of 1.5-2 mm.s, welding a second reinforcing rib at the upper end of the third reinforcing rib, after welding, welding current of 160-180A, welding voltage of 18-20V and welding speed of 2-2.5 mm.s, welding two ends of the second reinforcing rib with the left frame and the right frame respectively;
C. welding a middle bent beam: fixing the middle bent beam between the left frame and the right frame through a clamp, wherein the middle bent beam is positioned at the upper end of the third reinforcing rib, welding current is 140-170A, welding voltage is 16-18V, welding speed is 1.5-2mm · s, and two ends of the middle bent beam are respectively welded with the left frame and the right frame;
D. welding a window frame: fixing the window frame among the left frame, the right frame and the upper frame through a clamp, welding current 160-180A, welding voltage 18-20V, welding speed 2-2.5mm & s, wherein the left end and the right end of the top end of the window frame are provided with two welding points, one corner of the top end of the window frame is welded with the upper frame, the other corner of the top end of the window frame is welded with the upper frame, the left side wall and the right side wall of the window frame are symmetrically provided with six welding points, the left side wall and the right side wall of the window frame are sequentially subjected to left-right diagonal electric welding, the left end and the right end of the bottom end of the window frame are provided with two welding points, one corner of the bottom end of the window frame is welded with a reinforcing rib I, and the;
E. and (4) reversely installing the metro door framework, and reversely installing and welding the metro door framework according to the sequence of the normal installation welding and the welding parameters.
2. The subway door framework welding process as claimed in claim 1, wherein: the diameter of a nozzle used for alternating current pulse argon arc welding is 13mm, the argon flow is 8-10 L.min, and the distance between the nozzle and a workpiece is 8-12 mm.
3. The subway door framework welding process as claimed in claim 1, wherein: and B, performing surface treatment on the workpiece before welding in the steps A, B, C, D and E, wiping the surface of the workpiece by using acetone, and then directly polishing the metal by using a copper wire brush with the diameter of 0.16-0.18 mm.
4. The subway door framework welding process as claimed in claim 1, wherein: and B, performing surface treatment on the workpiece before welding in the step A, the step B, the step C, the step D and the step E, and performing pre-heating treatment on the metro door frame workpiece before welding, wherein the pre-heating temperature is 80-120 ℃.
5. The subway door framework welding process as claimed in claim 1, wherein: and C, performing surface treatment on the welding position of the workpiece after welding in the steps A, B, C, D and E, and polishing the welding position by using a copper wire brush with the diameter of 0.16-0.18 mm.
6. The subway door framework welding process as claimed in claim 1, wherein: and C, during welding in the step A, the step B, the step C, the step D and the step E, measuring the temperature of the welded workpiece through an infrared temperature measuring instrument, stopping welding when the temperature of the welded workpiece exceeds 80 ℃, and continuing welding after the temperature of the welded workpiece is reduced.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011573886.0A CN112620887A (en) | 2020-12-28 | 2020-12-28 | Subway door framework welding process |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011573886.0A CN112620887A (en) | 2020-12-28 | 2020-12-28 | Subway door framework welding process |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112620887A true CN112620887A (en) | 2021-04-09 |
Family
ID=75326018
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011573886.0A Pending CN112620887A (en) | 2020-12-28 | 2020-12-28 | Subway door framework welding process |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112620887A (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4103817A (en) * | 1975-07-03 | 1978-08-01 | The Chesapeake And Ohio Railway Company | Railway hopper car door frame assembly |
| CN104625344A (en) * | 2014-12-30 | 2015-05-20 | 辽宁忠旺集团有限公司 | Welding technology for blocking aluminum alloy side wall of subway compartment |
| CN206382784U (en) * | 2017-01-21 | 2017-08-08 | 青岛东创机械工程有限公司 | A kind of subway door leaf welding tooling |
| CN109822251A (en) * | 2019-03-27 | 2019-05-31 | 辽宁忠旺铝合金精深加工有限公司 | A kind of skeleton welding procedure of built-in subway passenger door |
-
2020
- 2020-12-28 CN CN202011573886.0A patent/CN112620887A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4103817A (en) * | 1975-07-03 | 1978-08-01 | The Chesapeake And Ohio Railway Company | Railway hopper car door frame assembly |
| CN104625344A (en) * | 2014-12-30 | 2015-05-20 | 辽宁忠旺集团有限公司 | Welding technology for blocking aluminum alloy side wall of subway compartment |
| CN206382784U (en) * | 2017-01-21 | 2017-08-08 | 青岛东创机械工程有限公司 | A kind of subway door leaf welding tooling |
| CN109822251A (en) * | 2019-03-27 | 2019-05-31 | 辽宁忠旺铝合金精深加工有限公司 | A kind of skeleton welding procedure of built-in subway passenger door |
Non-Patent Citations (1)
| Title |
|---|
| 马青梅: "铝合金地铁门骨架焊接变形控制工艺", 《金属加工（热加工）》 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103381518B (en) | A kind of aluminum alloy doors and windows welding procedure | |
| CN103357991A (en) | Horizontal fixed welding technology for aluminium process pipeline | |
| CN103464873B (en) | Electric-arc welding process for Ti alloy and nickel-base high-temperature alloy | |
| CN108857127B (en) | Welding method of frame type aluminum alloy car body top cover | |
| CN103551750A (en) | Welded pipe and manufacturing method thereof | |
| CN111037088A (en) | Welding process of friction stir welding | |
| CN105598596A (en) | Non-preheating combined welding method of 1200MPa high-strength steel | |
| CN112620887A (en) | Subway door framework welding process | |
| CN112247355A (en) | High-strength beta titanium alloy laser welding method | |
| CN104476141A (en) | Door window welding process | |
| CN214722191U (en) | Device for preparing copper-clad aluminum wire by laser welding | |
| CN110293276A (en) | A kind of Al alloy parts welding method | |
| CN110666294A (en) | Welding method for complex cross structure of weather-resistant steel sleeper beam of railway passenger car | |
| CN105033581A (en) | Method for compounding copper and aluminum dissimilar metal of zinc electrolysis cathode conductive head | |
| CN108015421A (en) | A kind of welding procedure of electrical switchgear aluminium alloy box | |
| CN101388583B (en) | Machining method for magnetic pole winding of four-angle welding motor | |
| CN111702302A (en) | Welding process of lightweight aluminum alloy vehicle door | |
| CN106271412A (en) | The bridge manufacture method of aluminium alloy deflector | |
| CN105195858A (en) | Flat-angle welding method for hull structural steel | |
| CN1323007C (en) | Production process of magnesium alloy bicycle frame | |
| CN107931789A (en) | A kind of door and window welding procedure | |
| CN213103425U (en) | Slag removal device for outer welding seam of longitudinal submerged arc welded pipe | |
| CN104240839A (en) | Method and system for manufacturing copper clad steel wire | |
| CN109940301B (en) | Automatic welding process for vehicle body side beam assembly | |
| CN105382381A (en) | Welding method of resistance strip of electrothermal furnace |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| CB02 | Change of applicant information |
Address after: No.18, middle section of Renmin Road, Yima City, Sanmenxia City, Henan Province Applicant after: HENAN ZHONGCHE HEAVY EQUIPMENT Co.,Ltd. Address before: No.18, middle section of Renmin Road, Yima City, Zhumadian City, Henan Province, 472300 Applicant before: HENAN ZHONGCHE HEAVY EQUIPMENT Co.,Ltd. |
|
| CB02 | Change of applicant information | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20210409 |
|
| WD01 | Invention patent application deemed withdrawn after publication |