CN111578818B - Thrust bearing thrust gap measuring device and gap measuring method - Google Patents
Thrust bearing thrust gap measuring device and gap measuring method Download PDFInfo
- Publication number
- CN111578818B CN111578818B CN202010277036.XA CN202010277036A CN111578818B CN 111578818 B CN111578818 B CN 111578818B CN 202010277036 A CN202010277036 A CN 202010277036A CN 111578818 B CN111578818 B CN 111578818B
- Authority
- CN
- China
- Prior art keywords
- standard disc
- thrust
- standard
- disc
- bearing bush
- 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.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B5/00—Measuring arrangements characterised by the use of mechanical techniques
- G01B5/14—Measuring arrangements characterised by the use of mechanical techniques for measuring distance or clearance between spaced objects or spaced apertures
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- A Measuring Device Byusing Mechanical Method (AREA)
Abstract
The invention provides a thrust bearing thrust clearance measuring device and a clearance measuring method, which belong to the field of turbine machinery, are used for measuring the thrust clearance of a sliding thrust bearing with a first bearing bush and a second bearing bush, and comprise a first standard disc, a second standard disc, a pre-tightening assembly and a top support piece; a test space for mounting a rotor thrust disc is arranged between the first bearing bush and the second bearing bush, the first standard disc is arranged on one side of the test space close to the first bearing bush, and the second standard disc is arranged on one side of the test space close to the second bearing bush; one end of the telescopic top support piece acts on the first standard disc, and the other end of the telescopic top support piece acts on the second standard disc; the pre-tightening assembly comprises a screw and an elastic piece, and the screw comprises a rod part and a head part; the rod part penetrates through the second standard disc to be connected with the first standard disc, one end of the elastic part acts on the head part, and the other end of the elastic part acts on the second standard disc, so that the second standard disc always has a motion trend close to the first standard disc. Simple structure, easy operation, the precision is higher.
Description
Technical Field
The invention relates to the field of turbine machinery, in particular to a thrust bearing thrust clearance measuring device and a clearance measuring method.
Background
At present, the sliding thrust bearing is widely applied to large-scale power generation equipment such as thermal power, nuclear power, gas turbines and the like due to the excellent characteristics of the sliding thrust bearing. In the field maintenance process of the bearing, the thrust clearance is important to check as a necessary item, but under the field condition, the field measurement can be carried out only by a method of pushing the rotor forwards and backwards at present, but with the method, along with the improvement of the unit power, the shaft system is lengthened and weighted, when the rotor is pushed, a small jack is used for pushing the rotor to not move, when a large jack is used, the rotor is deformed due to larger force in the moving process, the measured data has larger errors and even wrong phenomena, and great difficulty is caused to the field. The invention provides a thrust bearing thrust clearance measuring device which does not need to push a rotor and is simple to operate.
Disclosure of Invention
The invention provides a thrust bearing thrust clearance measuring device and a clearance measuring method, and aims to solve the problems of the thrust bearing thrust clearance measuring device and the clearance measuring method in the prior art.
The invention is realized by the following steps:
a thrust bearing thrust clearance measuring device is used for measuring the thrust clearance of a sliding thrust bearing with a first bearing bush and a second bearing bush and is characterized by comprising a first standard disc, a second standard disc, a pre-tightening assembly and a top support piece;
a test space for mounting a rotor thrust disc is arranged between the first bearing bush and the second bearing bush, the first standard disc is arranged on one side, close to the first bearing bush, of the test space, and the second standard disc is arranged on one side, close to the second bearing bush, of the test space;
one end of the telescopic top support piece acts on the first standard disc, and the other end of the telescopic top support piece acts on the second standard disc;
the pre-tightening assembly comprises a screw and an elastic piece, and the screw comprises a rod part and a head part;
the rod part penetrates through the second standard disc to be connected with the first standard disc, one end of the elastic piece acts on the head part, and the other end of the elastic piece acts on the second standard disc, so that the second standard disc always has a movement trend close to the first standard disc.
In one embodiment of the invention, the multifunctional electric heating cooker further comprises a first dial gauge, wherein the first dial gauge comprises a first frame body and a first side rod;
the first support body is fixed on the first bearing bush, and the first side rod acts on the first standard disc.
In one embodiment of the invention, the rack further comprises a second dial indicator, wherein the second dial indicator comprises a second rack body and a second side rod;
the second frame body is fixed on the second bearing bush, and the second side rod acts on the second standard disc.
In one embodiment of the present invention, the elastic member is a compression spring.
In one embodiment of the invention, the top support is a jack.
The clearance measuring method using the thrust clearance measuring device of the thrust bearing comprises the following steps:
the first standard disc and the second standard disc are spliced, and the pre-tightening assembly is adjusted, so that when the first standard disc and the second standard disc are attached, the elasticity of the elastic part is smaller than 2N;
measuring the total thickness of the first standard disk and the second standard disk as LC;
Measuring the actual size L of a rotor thrust disc;
installing the first standard disk and the second standard disk in the test space, and installing the first dial indicator and the second dial indicator;
the jacking piece applies preset thrust to push the first standard disc and the second standard disc away to obtain a reading A of the first dial indicator and a reading B of the second dial indicator;
by the formula K ═ LC+ A + B-L to obtain a thrust gap K.
The invention has the beneficial effects that: the thrust bearing thrust clearance measuring device provided by the invention has the advantages of simple structure, simplicity and convenience in operation, and higher precision, and the rotor does not need to be pushed when the thrust clearance is measured.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.
FIG. 1 is a cross-sectional view of a thrust bearing thrust gap measurement apparatus provided by an embodiment of the present invention;
icon: 010-a first bearing shell; 030-second bearing shoes; 100-a first standard disc; 200-a second standard disc; 300-pre-tightening assembly; 400-top stay; 500-first dial indicator; 600-a second dial indicator; 310-a screw; 330-elastic member.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings of the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention. Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.
In the description of the present invention, it is to be understood that the terms indicating an orientation or positional relationship are based on the orientation or positional relationship shown in the drawings only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.
In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
In the present invention, unless otherwise expressly stated or limited, the first feature may be present on or under the second feature in direct contact with the first and second feature, or may be present in the first and second feature not in direct contact but in contact with another feature between them. Also, the first feature being above, on or above the second feature includes the first feature being directly above and obliquely above the second feature, or merely means that the first feature is at a higher level than the second feature. A first feature that underlies, and underlies a second feature includes a first feature that is directly under and obliquely under a second feature, or simply means that the first feature is at a lesser level than the second feature.
Example one
Referring to fig. 1, the thrust bearing thrust gap measuring device for measuring the thrust gap of a sliding thrust bearing having a first bearing shoe 010 and a second bearing shoe 030 includes a first standard disk 100, a second standard disk 200, a preload assembly 300, and a top support 400.
Be provided with the test space that is used for installing rotor thrust disc between first axle bush 010 and the second axle bush 030, when using thrust bearing thrust clearance measuring device to measure, first standard dish 100 sets up in the one side that the test space is close to first axle bush 010, and second standard dish 200 sets up in the one side that the test space is close to second axle bush 030.
The telescopic top support 400 formed by the jack acts on the first standard plate 100 at one end and acts on the second standard plate 200 at the other end; the first standard disk 100 and the second standard disk 200 can be moved away from each other by a specified force by applying a force through a jack.
The pretensioning assembly 300 comprises a screw 310 and an elastic member 330, wherein the screw 310 comprises a shaft part and a head part; the shaft of the screw 310 passes through the second standard disk 200 and is connected to the first standard disk 100, and specifically, the shaft of the screw 310 passes through the first standard disk 100 after passing through the second standard disk 200, and a nut is provided at a portion extending from the first standard disk 100.
An elastic part 330 formed by a pressure spring is sleeved outside the rod part, one end of the elastic part 330 acts on the head part, and the other end acts on the second standard disc 200, so that the second standard disc 200 always has a movement trend close to the first standard disc 100.
The thrust bearing thrust clearance measuring device further comprises a first dial indicator 500 and a second dial indicator 600, and the first dial indicator 500 and the second dial indicator 600 are used for measuring the tiny displacement in the test process.
The first dial gauge 500 comprises a first frame body and a first side rod; the first frame is fixed on the first bearing bush 010, and the first side bar acts on the first standard disc 100. The second dial indicator 600 comprises a second frame body and a second side rod; the second frame is fixed to the second shoe 030 and the second side bar acts on the second standard plate 200.
That is, the first dial indicator 500 is used for measuring the displacement of the first standard disc 100 relative to the first bearing shell 010 after the jack applies force, and the second dial indicator 600 is used for measuring the displacement of the second standard disc 200 relative to the second bearing shell 030 after the jack applies force.
The thrust bearing thrust clearance measuring device provided by the invention has the advantages of simple structure, simplicity and convenience in operation, and higher precision, and the rotor does not need to be pushed when the thrust clearance is measured.
Example two
The embodiment provides a gap measurement method, which uses the thrust bearing thrust gap measurement device provided in the first embodiment to measure the thrust gap, and includes the steps of:
the first standard disc 100 and the second standard disc 200 are spliced, and the pre-tightening assembly 300 is adjusted, so that when the first standard disc 100 and the second standard disc 200 are attached, the elasticity of the elastic part 330 is less than 2N;
the total thickness of the first and second standard disks 100 and 200 was measured to be LC;
Measuring the actual size L of a rotor thrust disc;
installing the first standard disc 100 and the second standard disc 200 in the test space, and installing the first dial indicator 500 and the second dial indicator 600;
the jacking piece 400 applies a preset pushing force to push the first standard disc 100 and the second standard disc 200 apart to obtain a reading A of the first dial indicator 500 and a reading B of the second dial indicator 600;
by the formula K ═ LC+ A + B-L to obtain a thrust gap K.
The clearance measuring method provided by the invention is simple and convenient to operate and implement, and has higher precision because the rotor does not need to be pushed when the thrust clearance is measured.
The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes may be made to the present invention by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (4)
1. A thrust bearing thrust clearance measuring device is used for measuring the thrust clearance of a sliding thrust bearing with a first bearing bush and a second bearing bush and is characterized by comprising a first standard disc, a second standard disc, a pre-tightening assembly and a top support piece;
a test space for mounting a rotor thrust disc is arranged between the first bearing bush and the second bearing bush, the first standard disc is arranged on one side, close to the first bearing bush, of the test space, and the second standard disc is arranged on one side, close to the second bearing bush, of the test space;
one end of the telescopic top support piece acts on the first standard disc, and the other end of the telescopic top support piece acts on the second standard disc;
the pre-tightening assembly comprises a screw and an elastic piece, and the screw comprises a rod part and a head part;
the rod part penetrates through the second standard disc to be connected with the first standard disc, one end of the elastic piece acts on the head part, and the other end of the elastic piece acts on the second standard disc, so that the second standard disc always has a movement trend close to the first standard disc;
the first dial indicator comprises a first frame body and a first side rod;
the first frame body is fixed on the first bearing bush, and the first side rod acts on the first standard disc;
the second dial indicator comprises a second frame body and a second side rod;
the second frame body is fixed on the second bearing bush, and the second side rod acts on the second standard disc.
2. The thrust bearing thrust gap measurement device of claim 1, wherein the top brace is a jack.
3. The thrust bearing thrust gap measurement device of claim 1, wherein the resilient member is a compression spring.
4. A clearance measuring method using the thrust bearing thrust clearance measuring device according to claim 1, comprising the steps of:
the first standard disc and the second standard disc are spliced, and the pre-tightening assembly is adjusted, so that when the first standard disc and the second standard disc are attached, the elasticity of the elastic part is smaller than 2N;
measuring the total thickness of the first standard disk and the second standard disk as LC;
Measuring the actual size L of a rotor thrust disc;
installing the first standard disk and the second standard disk in the test space, and installing the first dial indicator and the second dial indicator;
the jacking piece applies preset thrust to push the first standard disc and the second standard disc away to obtain a reading A of the first dial indicator and a reading B of the second dial indicator;
by the formula K ═ LC+ A + B-L to obtain a thrust gap K.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202010277036.XA CN111578818B (en) | 2020-04-10 | 2020-04-10 | Thrust bearing thrust gap measuring device and gap measuring method |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202010277036.XA CN111578818B (en) | 2020-04-10 | 2020-04-10 | Thrust bearing thrust gap measuring device and gap measuring method |
Publications (2)
Publication Number | Publication Date |
---|---|
CN111578818A CN111578818A (en) | 2020-08-25 |
CN111578818B true CN111578818B (en) | 2021-12-21 |
Family
ID=72111530
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202010277036.XA Active CN111578818B (en) | 2020-04-10 | 2020-04-10 | Thrust bearing thrust gap measuring device and gap measuring method |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN111578818B (en) |
Citations (19)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6222039A (en) * | 1985-07-22 | 1987-01-30 | Mitsubishi Electric Corp | Detection device for thrust load on rotating machine |
CN101498577A (en) * | 2008-03-26 | 2009-08-05 | 中国计量科学研究院 | Accurate phase shift generating apparatus, accurate length measurement system and method thereof |
CN202083322U (en) * | 2011-05-13 | 2011-12-21 | 宝山钢铁股份有限公司 | Measurement device for thrust bearing clearances of phosphorus removal pump |
CN202433195U (en) * | 2011-12-31 | 2012-09-12 | 东方电气集团东方汽轮机有限公司 | Detection tool for contact status of bearing bush body and tile sleeve cooperation spherical surface |
CN202582449U (en) * | 2012-05-23 | 2012-12-05 | 广州飞机维修工程有限公司 | Axial gap measuring device of thrust bearing |
WO2013064942A1 (en) * | 2011-11-03 | 2013-05-10 | Rte Technologie Gmbh | Measuring device |
WO2014204942A1 (en) * | 2013-06-17 | 2014-12-24 | Seagate Technology Llc | Bearing gap determined depth and width |
CN104265651A (en) * | 2014-07-24 | 2015-01-07 | 扬州大学 | Turning measurement device and method of swing degree of upper operating oil pipe of hydraulic blade all-adjustable water pump |
JP5985055B2 (en) * | 2013-06-13 | 2016-09-06 | 三菱電機株式会社 | End play measuring device |
CN205835082U (en) * | 2016-04-28 | 2016-12-28 | 安徽电力股份有限公司淮南田家庵发电厂 | Non-load side bearing play measures special fixture |
CN106969687A (en) * | 2017-04-06 | 2017-07-21 | 苏州瑞美科材料科技有限公司 | A kind of slide clearance test device |
CN206905685U (en) * | 2017-04-01 | 2018-01-19 | 广州市巨安人防工程有限公司 | A kind of latch shaft axle sleeve detecting tool |
CN107717405A (en) * | 2017-10-12 | 2018-02-23 | 重庆齿轮箱有限责任公司 | A kind of thrust slide bearing gap and contact (area) pattern adjusting apparatus and method |
CN207703136U (en) * | 2018-01-11 | 2018-08-07 | 莱芜钢铁集团有限公司 | Plain bearing bush gap measuring apparatus |
CN207816155U (en) * | 2018-01-18 | 2018-09-04 | 北京丰荣航空科技股份有限公司 | Aircraft attachment axial gap measuring device |
CN208419829U (en) * | 2018-06-26 | 2019-01-22 | 宿迁正禾精密机械有限公司 | A kind of detection device for bearing end-play |
CN109405714A (en) * | 2018-12-13 | 2019-03-01 | 哈尔滨电气动力装备有限公司 | Reactor coolant pump thrust disc measurement of fit clearance device |
CN208833147U (en) * | 2018-10-24 | 2019-05-07 | 宁波益明轴承有限公司 | It is a kind of for detecting the cubing in bearing ball pocket gap |
CN209783492U (en) * | 2019-05-28 | 2019-12-13 | 宜宾天工机械股份有限公司 | Radial internal clearance detection device for needle bearing rocker arm |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NL123424C (en) * | 1960-06-08 | 1900-01-01 | ||
CN108458639B (en) * | 2018-01-18 | 2024-04-02 | 北京丰荣航空科技股份有限公司 | Device and method for measuring axial clearance of aircraft accessory |
-
2020
- 2020-04-10 CN CN202010277036.XA patent/CN111578818B/en active Active
Patent Citations (19)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6222039A (en) * | 1985-07-22 | 1987-01-30 | Mitsubishi Electric Corp | Detection device for thrust load on rotating machine |
CN101498577A (en) * | 2008-03-26 | 2009-08-05 | 中国计量科学研究院 | Accurate phase shift generating apparatus, accurate length measurement system and method thereof |
CN202083322U (en) * | 2011-05-13 | 2011-12-21 | 宝山钢铁股份有限公司 | Measurement device for thrust bearing clearances of phosphorus removal pump |
WO2013064942A1 (en) * | 2011-11-03 | 2013-05-10 | Rte Technologie Gmbh | Measuring device |
CN202433195U (en) * | 2011-12-31 | 2012-09-12 | 东方电气集团东方汽轮机有限公司 | Detection tool for contact status of bearing bush body and tile sleeve cooperation spherical surface |
CN202582449U (en) * | 2012-05-23 | 2012-12-05 | 广州飞机维修工程有限公司 | Axial gap measuring device of thrust bearing |
JP5985055B2 (en) * | 2013-06-13 | 2016-09-06 | 三菱電機株式会社 | End play measuring device |
WO2014204942A1 (en) * | 2013-06-17 | 2014-12-24 | Seagate Technology Llc | Bearing gap determined depth and width |
CN104265651A (en) * | 2014-07-24 | 2015-01-07 | 扬州大学 | Turning measurement device and method of swing degree of upper operating oil pipe of hydraulic blade all-adjustable water pump |
CN205835082U (en) * | 2016-04-28 | 2016-12-28 | 安徽电力股份有限公司淮南田家庵发电厂 | Non-load side bearing play measures special fixture |
CN206905685U (en) * | 2017-04-01 | 2018-01-19 | 广州市巨安人防工程有限公司 | A kind of latch shaft axle sleeve detecting tool |
CN106969687A (en) * | 2017-04-06 | 2017-07-21 | 苏州瑞美科材料科技有限公司 | A kind of slide clearance test device |
CN107717405A (en) * | 2017-10-12 | 2018-02-23 | 重庆齿轮箱有限责任公司 | A kind of thrust slide bearing gap and contact (area) pattern adjusting apparatus and method |
CN207703136U (en) * | 2018-01-11 | 2018-08-07 | 莱芜钢铁集团有限公司 | Plain bearing bush gap measuring apparatus |
CN207816155U (en) * | 2018-01-18 | 2018-09-04 | 北京丰荣航空科技股份有限公司 | Aircraft attachment axial gap measuring device |
CN208419829U (en) * | 2018-06-26 | 2019-01-22 | 宿迁正禾精密机械有限公司 | A kind of detection device for bearing end-play |
CN208833147U (en) * | 2018-10-24 | 2019-05-07 | 宁波益明轴承有限公司 | It is a kind of for detecting the cubing in bearing ball pocket gap |
CN109405714A (en) * | 2018-12-13 | 2019-03-01 | 哈尔滨电气动力装备有限公司 | Reactor coolant pump thrust disc measurement of fit clearance device |
CN209783492U (en) * | 2019-05-28 | 2019-12-13 | 宜宾天工机械股份有限公司 | Radial internal clearance detection device for needle bearing rocker arm |
Non-Patent Citations (3)
Title |
---|
Thrust actuator with passive restoration force for wide gap magnetic bearings;Royo-Silvestre;《JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS》;20190415;第342-348页 * |
刚性转子现场动平衡理论分析及实验研究;孙延添;《中国优秀博硕士学位论文全文数据库 (硕士)工程科技Ⅱ辑》;20060815(第08期);第C029-9页 * |
浅谈汽轮机安装检修中的间隙测量与调整;张立祥;《中国设备工程》;20190910;第24-25页 * |
Also Published As
Publication number | Publication date |
---|---|
CN111578818A (en) | 2020-08-25 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN103376192A (en) | Spring detection device | |
CN111578818B (en) | Thrust bearing thrust gap measuring device and gap measuring method | |
CN102998254A (en) | Micro friction force measuring device | |
CN102519798B (en) | Device and method for measuring stiffness of canted coil spring | |
CN113340804A (en) | Test device for accurately measuring static friction coefficient | |
CN219996138U (en) | Mechanical sensing type hydropower station spindle swing degree detection device | |
CN213090999U (en) | Fixing support for high-precision temperature measurement type temperature sensor | |
CN116164873B (en) | Temperature compensation method and device for six-dimensional force sensor | |
CN210863973U (en) | Stator performance detection equipment | |
CN214372116U (en) | Detection tool for measuring gear shaft diameter installation position | |
CN103398805B (en) | Three-dimensional nanometer measurement head elastically supported by spiral leaf spring | |
CN216160160U (en) | Coupling torque measuring machine | |
CN214309058U (en) | Vehicle-mounted dynamic weighing module | |
WO2018185483A1 (en) | Preload force tool | |
CN109374521B (en) | Device for testing friction energy consumption performance of metal rubber and working method thereof | |
CN216791085U (en) | Measuring device for mounting eccentricity of cartridge receiver | |
CN218765181U (en) | Displacement sensor | |
CN219103934U (en) | Floating height detection device | |
CN111707398B (en) | Automatic loading device for upper friction pair | |
CN218326913U (en) | High-frequency resonance-free vibration-damping compression spring device | |
CN220251060U (en) | Anti-drop's instrument and meter detection device | |
CN211452278U (en) | Bearing play detection device | |
CN218787792U (en) | Bearing radial play detection device | |
CN219284225U (en) | Gap measuring device of recirculating ball electric steering device | |
CN210533584U (en) | Torque testing device |
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 | ||
GR01 | Patent grant | ||
GR01 | Patent grant |