CN110848270A - Sealed roller bearing and backing roll supporting mechanism of rolling mill thereof - Google Patents
Sealed roller bearing and backing roll supporting mechanism of rolling mill thereof Download PDFInfo
- Publication number
- CN110848270A CN110848270A CN201911222180.7A CN201911222180A CN110848270A CN 110848270 A CN110848270 A CN 110848270A CN 201911222180 A CN201911222180 A CN 201911222180A CN 110848270 A CN110848270 A CN 110848270A
- Authority
- CN
- China
- Prior art keywords
- bearing
- outer ring
- roller bearing
- ring
- sealed roller
- 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.)
- Withdrawn
Links
- 238000005096 rolling process Methods 0.000 title claims abstract description 28
- 238000007789 sealing Methods 0.000 claims abstract description 47
- 239000012535 impurity Substances 0.000 claims abstract description 12
- 239000002184 metal Substances 0.000 claims description 4
- 239000000110 cooling liquid Substances 0.000 abstract description 7
- 238000009434 installation Methods 0.000 description 7
- 230000000295 complement effect Effects 0.000 description 3
- 239000007788 liquid Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000002826 coolant Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000008676 import Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
- F16C33/72—Sealings
- F16C33/76—Sealings of ball or roller bearings
- F16C33/78—Sealings of ball or roller bearings with a diaphragm, disc, or ring, with or without resilient members
- F16C33/7803—Sealings of ball or roller bearings with a diaphragm, disc, or ring, with or without resilient members suited for particular types of rolling bearings
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B31/00—Rolling stand structures; Mounting, adjusting, or interchanging rolls, roll mountings, or stand frames
- B21B31/07—Adaptation of roll neck bearings
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B31/00—Rolling stand structures; Mounting, adjusting, or interchanging rolls, roll mountings, or stand frames
- B21B31/07—Adaptation of roll neck bearings
- B21B31/078—Sealing devices
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
- F16C33/72—Sealings
- F16C33/76—Sealings of ball or roller bearings
- F16C33/78—Sealings of ball or roller bearings with a diaphragm, disc, or ring, with or without resilient members
- F16C33/7816—Details of the sealing or parts thereof, e.g. geometry, material
- F16C33/782—Details of the sealing or parts thereof, e.g. geometry, material of the sealing region
- F16C33/7823—Details of the sealing or parts thereof, e.g. geometry, material of the sealing region of sealing lips
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C2322/00—Apparatus used in shaping articles
- F16C2322/12—Rolling apparatus, e.g. rolling stands, rolls
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Rolling Contact Bearings (AREA)
Abstract
The invention relates to a sealed roller bearing, which comprises a bearing outer ring, a bearing inner ring, a roller assembly and two retainer rings, wherein the bearing outer ring is arranged on the bearing inner ring; sealing elements are arranged between the outer wall surfaces of the two retaining rings and the inner wall surface of the bearing outer ring, and the sealing elements are arranged on the retaining rings; when positive pressure oil gas exists in the raceway, an exhaust gap is formed between the sealing element and the bearing outer ring; when non-positive pressure oil gas exists in the raceway, an exhaust gap between the sealing element and the bearing outer ring is closed so as to prevent external impurities from entering the pipeline. A back roll support mechanism for a rolling mill is provided, comprising a back roll and side support rolls, wherein 13 sealed roller bearings are arranged on the back roll. So as to prevent the cooling liquid on the rolling mill from entering the rest sealed roller bearings and prolong the service life of the sealed roller bearings on the back lining roller.
Description
Technical Field
The invention relates to a sealed roller bearing and a backing roll supporting mechanism of a rolling mill thereof.
Background
The eighteen-roller rolling mill shown in fig. 1 comprises an upper working roller 51 and a lower working roller 51, wherein each working roller 51 is respectively provided with two side supporting rollers 52 and a middle roller 54, each middle roller 54 is provided with a large supporting roller 55, and each side supporting roller 52 is provided with two backing rollers 53 for supporting, and the traditional supporting structure is as follows: the backing roller 53 is provided with a set of bearings, and the two backing rollers 53 respectively realize rolling support for the single side support roller 52 through two sets of bearings.
Conventionally, 13 roller bearings are generally arranged on a backing roll 53, in order to prevent rolling in the rolling process from entering a roller path of the roller bearing, each roller bearing is communicated with an oil-gas system, oil gas enters the roller bearing from an inner ring 42 of the roller bearing, and the purpose is to keep the air pressure in the roller bearing at positive pressure so as to prevent external impurities from entering the roller bearing, the conventional roller bearing has the problems that as shown in fig. 2, the conventional roller bearing comprises an inner ring 42, an outer ring 41 and a retainer ring 43, two snap springs 44 are arranged between the retainer ring 43 and the inner ring 42, radial moving gaps exist between the retainer ring 43 and the outer ring 41 for the two snap springs 44, during operation, the positive-pressure oil gas in the roller bearing is discharged outwards through the two snap springs 44 so as to prevent external impurity liquid from entering the roller bearing, when a certain roller bearing needs to be replaced, all the oil-gas systems of the roller bearing are stopped, after oil and gas stops, under the condition that the roller bearing is under non-positive pressure, impurities in cooling liquid can enter the roller bearing when the external rolling mill works, and therefore the service life of the roller bearing is affected.
Therefore, as described above, the conventional rolling mill has a relatively low service life for the roller bearing, and has problems in that: when the roller bearing is in an oil-gas non-positive pressure state, impurities in the cooling liquid of the external rolling mill easily enter the roller bearing, and the service life of the roller bearing is influenced.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: the defects of the prior art are overcome, the sealing roller bearing is provided, and the problem that the roller bearing is in a non-positive pressure state, external impurities easily enter the roller bearing, and the service life of the roller bearing is influenced is solved.
The utility model provides a back lining roller supporting mechanism of rolling mill, solves in the past rolling mill, when changing the pipe bearing on the back lining roller, the coolant liquid on the rolling mill easily enters the inside of roller bearing, influences the problem of roller bearing life.
The technical scheme adopted by the invention for solving the technical problems is as follows: a sealed roller bearing comprises a bearing outer ring, a bearing inner ring, a roller assembly and two retainer rings, wherein the bearing inner ring and the two retainer rings are positioned in the bearing outer ring, the two retainer rings are respectively abutted against two sides of the bearing inner ring, a raceway is formed between the bearing inner ring and the bearing outer ring, and the roller assembly is arranged in the raceway;
sealing elements are arranged between the outer wall surfaces of the two retaining rings and the inner wall surface of the bearing outer ring, and the sealing elements are arranged on the retaining rings;
when positive pressure oil gas exists in the raceway, an exhaust gap is formed between the sealing element and the bearing outer ring; when non-positive pressure oil gas exists in the raceway, an exhaust gap between the sealing element and the bearing outer ring is closed so as to prevent external impurities from entering the pipeline.
Further, the sealing member includes supporter and an at least lip seal, the supporter cup joints on the retainer plate, lip seal one end is connected with the supporter, the lip seal other end and bearing inner race inner wall elastic fit are suitable for when malleation oil gas discharges with the formation exhaust clearance.
Further, the sealing lip is arranged obliquely towards the outer side.
Further, the number of the sealing lips is two.
Furthermore, the cross section of the support body is of an L-shaped structure, and an L-shaped metal plate is arranged in the support body.
Furthermore, the outer wall of the retainer ring forms an installation step, a step opening of the installation step is arranged towards the inner side of the pipeline, and the support body of the sealing element is arranged on the installation step.
In yet another aspect, a backup roll support mechanism for a rolling mill is provided comprising a backup roll having 13 sealed roller bearings disposed thereon and side support rolls.
The invention has the beneficial effects that:
the utility model provides a sealed roller bearing, when the raceway has non-malleation oil gas, the exhaust clearance between sealing member and the bearing inner race is closed to block in outside impurity gets into the pipeline, avoid impurity corruption pipe subassembly, promote sealed roller bearing's life.
A backup roll supporting mechanism of a rolling mill is provided, wherein after the above-mentioned sealed roller bearing is adopted, when one sealed roller bearing on the backup roll of the rolling mill is replaced, the sealing lip in the sealed roller bearing can close the exhaust gap to prevent the cooling liquid on the rolling mill from entering the rest sealed roller bearings, thereby prolonging the service life of the sealed roller bearing on the backup roll.
Drawings
The invention is further described below with reference to the accompanying drawings.
FIG. 1 is a schematic view of a rolling mill;
51, a working roll, 52, side supporting rolls, 53, a backing roll, 54, a middle roll, 55 and a large supporting roll;
FIG. 2 is a schematic view of a prior art roller bearing;
41, an outer ring, 42, an inner ring, 43, a retainer ring, 44 and a clamp spring;
FIG. 3 is a schematic view of a sealed roller bearing of the present invention;
FIG. 4 is a schematic view of a seal ring;
FIG. 5 is a support structure between a mill backing roll and side support rolls;
the bearing comprises a full complement roller bearing 2, a bearing outer ring 21, a bearing inner ring 22, a bearing inner ring 23, a retainer ring 3, a sealing element 31, a supporting body 32 and a sealing lip.
Detailed Description
The invention will now be further described with reference to specific examples. These drawings are simplified schematic diagrams only illustrating the basic structure of the present invention in a schematic manner, and thus show only the constitution related to the present invention.
Example one
As shown in fig. 3 and 4, a sealed roller bearing includes a bearing outer ring 21, a bearing inner ring 22, a roller assembly and two retainer rings 23, where the bearing inner ring 22 and the two retainer rings 23 are located in the bearing outer ring 21, the two retainer rings 23 are respectively abutted against two sides of the bearing inner ring 22, a raceway is formed between the bearing inner ring 22 and the bearing outer ring 21, and the roller assembly is disposed in the raceway; sealing elements 3 are arranged between the outer wall surfaces of the two retaining rings 23 and the inner wall surface of the bearing outer ring 21, and the sealing elements 3 are arranged on the retaining rings 23;
when positive pressure oil gas exists in the raceway, an exhaust gap is formed between the sealing element 3 and the bearing outer ring 21; when non-positive pressure oil gas exists in the raceway, an exhaust gap between the sealing element 3 and the bearing outer ring 21 is closed, so that external impurities are prevented from entering the pipeline.
Specifically, in this embodiment, the sealing member 3 includes a supporting body 31 and two sealing lips 32, the supporting body 31 is sleeved on the retainer ring 23, one end of the sealing lip 32 is connected with the supporting body 31, and the other end of the sealing lip 32 is elastically matched with the inner wall of the bearing outer ring 21, so as to form the exhaust gap when positive pressure oil gas is discharged.
Specifically, in the present embodiment, the two sealing lips 32 are disposed to be inclined toward the outside, and the inclined disposition makes it more difficult for foreign matters to enter the raceway through the sealing member.
Specifically, in this embodiment, the cross section of the supporting body 31 is an L-shaped structure, an L-shaped metal plate is disposed in the supporting body 31, the metal plate is used to enhance the supporting strength of the whole supporting member, and the supporting member and the two sealing lips 32 are integrated into a whole.
Specifically, in the present embodiment, the mounting structure between the seal 3 and the retainer ring 23 is: the outer wall of the retainer ring 23 forms an installation step, the step opening of the installation step is arranged towards the inner side of the pipeline, and the support body 31 of the sealing element 3 is arranged on the installation step.
This mounting structure makes the installation of sealing member 3 more convenient, also can be more stable to the mounted position structure of sealing member 3.
In this embodiment, the selected roller bearing is the full complement roller bearing 2, the full complement roller bearing 2 is that the inner roller assembly does not contain a retainer, rollers are arranged in the raceway and do not contain a retainer, the number of rollers is increased, and accordingly, the load capacity of the roller bearing is improved.
In this embodiment, retaining ring 23 of bearing inner race 22 and both sides is fixed setting, bearing inner race 21 is rotatory, sealing member 3 is fixed on retaining ring 23, set up the oil gas import on the bearing inner race 22, oil gas access connection oil gas system, oil gas that oil gas system provided gets into in the raceway, then go out from exhaust gap, oil gas is lubricated inside roller on the one hand, on the other hand is used for making the raceway keep the malleation, prevent that external impurity from getting into, this part of roller bearing belongs to prior art to oil gas system connection, just use this kind of technique on the rolling mill at present.
The sealing structure of the roller bearing is improved, when oil gas in the roller bearing is in non-positive pressure (namely, an oil gas system is closed), the sealing lip 32 can be closed in time, external cooling liquid is prevented from entering a roller path of the roller bearing, and the phenomenon that the cooling liquid corrodes the roller and influences the service life of the roller is avoided.
Example two
As shown in fig. 5, a backing roll supporting mechanism of a rolling mill is an eighteen rolling mill, which comprises two backing rolls and side supporting rolls, wherein 13 sealing roller bearings are arranged on the backing rolls, and the 13 sealing roller bearings are axially locked and fixed on the backing rolls, so that the backing rolls do not rotate during the operation of the rolling mill, therefore, the bearing inner rings 22, the retainer rings 23 and the sealing elements 3 do not rotate, and the bearing outer rings 21 and the side supporting rolls form rolling contact matching to support the side supporting rolls;
in this embodiment, the above-mentioned sealed roller bearings are installed on the backing roll, when one of the sealed roller bearings is damaged and needs to be replaced, the oil-gas system of the rolling mill stops supplying oil gas into the bearing, at this time, because of lack of air pressure in each sealed roller bearing, the two sealing lips 32 in the sealing member 3 will automatically close on the outer ring 21 of the bearing, the exhaust gap is closed, and the cooling liquid of the rolling mill is prevented from entering the sealed roller bearing.
In light of the foregoing description of the preferred embodiment of the present invention, many modifications and variations will be apparent to those skilled in the art without departing from the spirit and scope of the invention. The technical scope of the present invention is not limited to the content of the specification, and must be determined according to the scope of the claims.
Claims (7)
1. A sealed roller bearing is characterized by comprising a bearing outer ring, a bearing inner ring, a roller assembly and two retainer rings, wherein the bearing inner ring and the two retainer rings are positioned in the bearing outer ring, the two retainer rings are respectively abutted against two sides of the bearing inner ring, a raceway is formed between the bearing inner ring and the bearing outer ring, and the roller assembly is arranged in the raceway;
sealing elements are arranged between the outer wall surfaces of the two retaining rings and the inner wall surface of the bearing outer ring, and the sealing elements are arranged on the retaining rings;
when positive pressure oil gas exists in the raceway, an exhaust gap is formed between the sealing element and the bearing outer ring; when non-positive pressure oil gas exists in the raceway, an exhaust gap between the sealing element and the bearing outer ring is closed so as to prevent external impurities from entering the pipeline.
2. The sealed roller bearing of claim 1, wherein the seal comprises a support body and at least one sealing lip, the support body is sleeved on the retainer ring, one end of the sealing lip is connected with the support body, and the other end of the sealing lip is elastically matched with the inner wall of the outer ring of the bearing and is suitable for forming the exhaust gap when positive pressure oil gas is exhausted.
3. The sealed roller bearing of claim 2, wherein said seal lip is disposed obliquely to an outer side.
4. The sealed roller bearing of claim 2, wherein said sealing lips are two in number.
5. The sealed roller bearing of claim 2, wherein said support body is L-shaped in cross-section, and wherein an L-shaped metal plate is disposed within said support body.
6. The sealed roller bearing of claim 1, wherein said retainer ring outer wall defines a mounting step, the step mouth of said mounting step being disposed toward the inside of the tube, said seal support body being disposed on said mounting step.
7. A backup roll support mechanism for a rolling mill comprising a backup roll and side support rolls, said backup roll having a plurality of sealed roller bearings as claimed in any one of claims 1 to 6 disposed thereon.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911222180.7A CN110848270A (en) | 2019-12-03 | 2019-12-03 | Sealed roller bearing and backing roll supporting mechanism of rolling mill thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911222180.7A CN110848270A (en) | 2019-12-03 | 2019-12-03 | Sealed roller bearing and backing roll supporting mechanism of rolling mill thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110848270A true CN110848270A (en) | 2020-02-28 |
Family
ID=69607438
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911222180.7A Withdrawn CN110848270A (en) | 2019-12-03 | 2019-12-03 | Sealed roller bearing and backing roll supporting mechanism of rolling mill thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110848270A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112412986A (en) * | 2020-11-23 | 2021-02-26 | 吕梁学院 | Coal-winning machine walking wheel bearing of convenient maintenance |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203770420U (en) * | 2013-12-27 | 2014-08-13 | 瓦房店轴承集团有限责任公司 | Pressure control thick-wall bearing with double-barb external buckle type sealing check ring |
| CN204025367U (en) * | 2014-06-23 | 2014-12-17 | 奥新（厦门）轴承有限公司 | With the agricultural machinery bearing support of special seal |
| CN107350287A (en) * | 2017-07-21 | 2017-11-17 | 中冶南方工程技术有限公司 | A kind of collateral support arrangement of the working roll of eighteen-high mill |
| CN211082585U (en) * | 2019-12-03 | 2020-07-24 | 常州克劳诺斯特种轴承制造有限公司 | Sealed roller bearing and backing roll supporting mechanism of rolling mill thereof |
-
2019
- 2019-12-03 CN CN201911222180.7A patent/CN110848270A/en not_active Withdrawn
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203770420U (en) * | 2013-12-27 | 2014-08-13 | 瓦房店轴承集团有限责任公司 | Pressure control thick-wall bearing with double-barb external buckle type sealing check ring |
| CN204025367U (en) * | 2014-06-23 | 2014-12-17 | 奥新（厦门）轴承有限公司 | With the agricultural machinery bearing support of special seal |
| CN107350287A (en) * | 2017-07-21 | 2017-11-17 | 中冶南方工程技术有限公司 | A kind of collateral support arrangement of the working roll of eighteen-high mill |
| CN211082585U (en) * | 2019-12-03 | 2020-07-24 | 常州克劳诺斯特种轴承制造有限公司 | Sealed roller bearing and backing roll supporting mechanism of rolling mill thereof |
Non-Patent Citations (1)
| Title |
|---|
| 黄志坚: "《轧机轧辊与轴承使用维修技术》", 31 January 2008, 冶金工业出版社, pages: 64 - 67 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112412986A (en) * | 2020-11-23 | 2021-02-26 | 吕梁学院 | Coal-winning machine walking wheel bearing of convenient maintenance |
| CN112412986B (en) * | 2020-11-23 | 2022-05-03 | 吕梁学院 | Coal-winning machine walking wheel bearing of convenient maintenance |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN201428739Y (en) | Sealing self-aligning roller bearing | |
| US6428212B1 (en) | Lubricating structure of bearing | |
| CN211082585U (en) | Sealed roller bearing and backing roll supporting mechanism of rolling mill thereof | |
| CN110848270A (en) | Sealed roller bearing and backing roll supporting mechanism of rolling mill thereof | |
| CN201916352U (en) | Spring steel skeleton two-row full complement cylinder roller bearing | |
| CN202732690U (en) | Backing bearing | |
| JP2008256160A (en) | Bearing device | |
| CN201347960Y (en) | Double-row cylindrical roller bearing with internal block and external block for rolling mill | |
| CN208474321U (en) | A kind of automobile bearing of low wear rate | |
| CN2597739Y (en) | Hub bearing | |
| CN211218033U (en) | Backing roll and side support roll support structure for rolling mill | |
| CN210715609U (en) | Combined seal for cold rolling mill roller seat | |
| CN102086904A (en) | Integral sealed double-row tapered roller bearing | |
| JP2001090737A (en) | Lubricating structure for bearing | |
| CN111927890A (en) | Novel contact type sealing ring and rolling mill supporting roller bearing applying same | |
| CN221195757U (en) | Corrosion-resistant deep groove ball bearing | |
| CN101769324A (en) | Four-row tapered roller bearing used for non-closed type rolling mills | |
| CN101769323A (en) | Four-row tapered roller bearing provided with oil guiding slots and used for rolling mills | |
| CN201228726Y (en) | Backing bearing | |
| CN101769320A (en) | Double-row tapered roller bearing provided with middle space rings and used for rolling mills | |
| JP2008223883A (en) | Lubricating device and rolling bearing | |
| SU1754244A1 (en) | Bearing assembly of heavy-load rolling roll | |
| CN216241873U (en) | Oil-gas lubricating structure of supporting roll shaft | |
| CN216175334U (en) | Back-up roll device of plate strip cold rolling mill | |
| CN220956805U (en) | Sealing device for spindle of steel cord water tank cone pulley |
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 | ||
| WW01 | Invention patent application withdrawn after publication |
Application publication date: 20200228 |