GB2324352A - Device incorporating elastic fluids and viscous damping - Google Patents
Device incorporating elastic fluids and viscous dampingInfo
- Publication number
- GB2324352A GB2324352A GB9812854A GB9812854A GB2324352A GB 2324352 A GB2324352 A GB 2324352A GB 9812854 A GB9812854 A GB 9812854A GB 9812854 A GB9812854 A GB 9812854A GB 2324352 A GB2324352 A GB 2324352A
- Authority
- GB
- United Kingdom
- Prior art keywords
- flexible walled
- device incorporating
- viscous damping
- incorporating elastic
- elastic fluids
- 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.)
- Granted
Links
- 238000013016 damping Methods 0.000 title 1
- 239000012530 fluid Substances 0.000 title 1
- 239000007788 liquid Substances 0.000 abstract 2
- 239000006096 absorbing agent Substances 0.000 abstract 1
- 239000002828 fuel tank Substances 0.000 abstract 1
- 238000004519 manufacturing process Methods 0.000 abstract 1
- 238000000034 method Methods 0.000 abstract 1
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
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F9/00—Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium
- F16F9/30—Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium with solid or semi-solid material, e.g. pasty masses, as damping medium
-
- A—HUMAN NECESSITIES
- A41—WEARING APPAREL
- A41D—OUTERWEAR; PROTECTIVE GARMENTS; ACCESSORIES
- A41D13/00—Professional, industrial or sporting protective garments, e.g. surgeons' gowns or garments protecting against blows or punches
-
- A—HUMAN NECESSITIES
- A43—FOOTWEAR
- A43B—CHARACTERISTIC FEATURES OF FOOTWEAR; PARTS OF FOOTWEAR
- A43B13/00—Soles; Sole-and-heel integral units
- A43B13/14—Soles; Sole-and-heel integral units characterised by the constructive form
- A43B13/18—Resilient soles
- A43B13/187—Resiliency achieved by the features of the material, e.g. foam, non liquid materials
-
- A—HUMAN NECESSITIES
- A43—FOOTWEAR
- A43B—CHARACTERISTIC FEATURES OF FOOTWEAR; PARTS OF FOOTWEAR
- A43B13/00—Soles; Sole-and-heel integral units
- A43B13/14—Soles; Sole-and-heel integral units characterised by the constructive form
- A43B13/18—Resilient soles
- A43B13/189—Resilient soles filled with a non-compressible fluid, e.g. gel, water
-
- A—HUMAN NECESSITIES
- A43—FOOTWEAR
- A43B—CHARACTERISTIC FEATURES OF FOOTWEAR; PARTS OF FOOTWEAR
- A43B3/00—Footwear characterised by the shape or the use
- A43B3/34—Footwear characterised by the shape or the use with electrical or electronic arrangements
-
- A—HUMAN NECESSITIES
- A43—FOOTWEAR
- A43B—CHARACTERISTIC FEATURES OF FOOTWEAR; PARTS OF FOOTWEAR
- A43B7/00—Footwear with health or hygienic arrangements
- A43B7/32—Footwear with health or hygienic arrangements with shock-absorbing means
-
- A—HUMAN NECESSITIES
- A62—LIFE-SAVING; FIRE-FIGHTING
- A62B—DEVICES, APPARATUS OR METHODS FOR LIFE-SAVING
- A62B35/00—Safety belts or body harnesses; Similar equipment for limiting displacement of the human body, especially in case of sudden changes of motion
- A62B35/04—Safety belts or body harnesses; Similar equipment for limiting displacement of the human body, especially in case of sudden changes of motion incorporating energy absorbing means
-
- A—HUMAN NECESSITIES
- A62—LIFE-SAVING; FIRE-FIGHTING
- A62C—FIRE-FIGHTING
- A62C3/00—Fire prevention, containment or extinguishing specially adapted for particular objects or places
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60K—ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
- B60K15/00—Arrangement in connection with fuel supply of combustion engines or other fuel consuming energy converters, e.g. fuel cells; Mounting or construction of fuel tanks
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
- B60R21/00—Arrangements or fittings on vehicles for protecting or preventing injuries to occupants or pedestrians in case of accidents or other traffic risks
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64D—EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT
- B64D25/00—Emergency apparatus or devices, not otherwise provided for
-
- 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
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F5/00—Liquid springs in which the liquid works as a spring by compression, e.g. combined with throttling action; Combinations of devices including liquid springs
-
- 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
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F9/00—Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium
- F16F9/003—Dampers characterised by having pressure absorbing means other than gas, e.g. sponge rubber
-
- 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
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F9/00—Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium
- F16F9/32—Details
- F16F9/53—Means for adjusting damping characteristics by varying fluid viscosity, e.g. electromagnetically
-
- D—TEXTILES; PAPER
- D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
- D06F—LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES
- D06F37/00—Details specific to washing machines covered by groups D06F21/00 - D06F25/00
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Health & Medical Sciences (AREA)
- Business, Economics & Management (AREA)
- General Health & Medical Sciences (AREA)
- Emergency Management (AREA)
- Public Health (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Chemical & Material Sciences (AREA)
- Sustainable Development (AREA)
- Sustainable Energy (AREA)
- Physical Education & Sports Medicine (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Life Sciences & Earth Sciences (AREA)
- Aviation & Aerospace Engineering (AREA)
- Epidemiology (AREA)
- Textile Engineering (AREA)
- Combustion & Propulsion (AREA)
- Transportation (AREA)
- Materials Engineering (AREA)
- Fluid-Damping Devices (AREA)
- Vibration Dampers (AREA)
Abstract
This invention relates to an improved shock-absorber device (6) comprising numerous small hollow flexible walled bodies which are preferably at least paritally gas-filled and are suspended in a liquid or gel medium and confined by a flexible walled vessel (1) or piston and cylinder arrangement. The device reduces the energy of impacts and also exploits the hydraulic properties of liquids to spread the force of an impact over a wider area. Many variations of the device of interest to travel, sports, medical, manufacturing and civil engineering industries are described. It offers a novel solution to the problem of exploding fuel tanks in aircraft and new methods of improving safety and comfort in motor vehicles. A "smart" active version of the device is also proposed.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB9812854A GB2324352B (en) | 1996-01-05 | 1996-12-31 | Device incorporating elastic fluids and viscous damping |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GBGB9600201.9A GB9600201D0 (en) | 1996-01-05 | 1996-01-05 | Tuneable visco-elastic fluids |
GBGB9605622.1A GB9605622D0 (en) | 1996-01-05 | 1996-03-18 | Tuneable visco-elastic fluids |
GB9812854A GB2324352B (en) | 1996-01-05 | 1996-12-31 | Device incorporating elastic fluids and viscous damping |
PCT/GB1996/003243 WO1997025551A2 (en) | 1996-01-05 | 1996-12-31 | Device incorporating elastic fluids and viscous damping |
Publications (3)
Publication Number | Publication Date |
---|---|
GB9812854D0 GB9812854D0 (en) | 1998-08-12 |
GB2324352A true GB2324352A (en) | 1998-10-21 |
GB2324352B GB2324352B (en) | 1999-10-20 |
Family
ID=27268067
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB9812854A Expired - Fee Related GB2324352B (en) | 1996-01-05 | 1996-12-31 | Device incorporating elastic fluids and viscous damping |
Country Status (1)
Country | Link |
---|---|
GB (1) | GB2324352B (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2002021013A1 (en) | 2000-09-06 | 2002-03-14 | William Alexander Courtney | Fluid filled impact absorber |
US9056983B2 (en) | 2011-09-09 | 2015-06-16 | Purdue Research Foundation | Dynamic load-absorbing materials and articles |
US9394959B2 (en) | 2011-09-09 | 2016-07-19 | Purdue Research Foundation | Dynamic load-absorbing material and articles |
US9839250B2 (en) | 2011-09-09 | 2017-12-12 | Purdue Research Foundation | Dynamic load-absorbing materials and articles |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6500173B2 (en) | 1992-01-07 | 2002-12-31 | Ronald A. Underwood | Methods for electrosurgical spine surgery |
Citations (25)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2873963A (en) * | 1954-11-09 | 1959-02-17 | Paul H Taylor | Liquid spring and oleo suspension for aircraft and vehicles |
US3990512A (en) * | 1975-07-10 | 1976-11-09 | Ultrasonic Energy Corporation | Method and system for ultrasonic oil recovery |
US3992002A (en) * | 1975-02-18 | 1976-11-16 | Pitney-Bowes, Inc. | Sheet registering apparatus |
DE2701181A1 (en) * | 1977-01-13 | 1978-07-20 | Picker | Resilient filling material for suspension unit - comprising suspension of fluid and hollow polymer particles with closed elastic casings (NL 17.7.78) |
FR2384996A1 (en) * | 1977-03-22 | 1978-10-20 | Trenkamp & Gehle | SUSPENSION DEVICE, IN PARTICULAR FOR VEHICLE AXLES |
JPS5516546A (en) * | 1978-07-20 | 1980-02-05 | Matsushita Electric Ind Co Ltd | Dynamic loudspeaker |
DE2841995A1 (en) * | 1978-09-27 | 1980-04-10 | Continental Gummi Werke Ag | Hydropneumatic shock absorber - comprises cellular rubber core with solid skin vulcanised onto it |
FR2534998A1 (en) * | 1982-10-25 | 1984-04-27 | Imp Clevite Inc | DRY VISCOUS ELASTIC SHOCK ABSORBER |
FR2534997A1 (en) * | 1982-10-25 | 1984-04-27 | Imp Clevite Inc | FLEXIBLE WALL ELASTIC SHOCK ABSORBER |
US4560042A (en) * | 1984-04-30 | 1985-12-24 | General Motors Corporation | Method of self-pressurizing a damper |
US4566565A (en) * | 1984-04-30 | 1986-01-28 | General Motors Corporation | Self-pressurized damper |
US4607586A (en) * | 1985-03-25 | 1986-08-26 | Taquino Weldon P | Preloaded compression absorber cell for boat bumpers |
JPS621139A (en) * | 1978-03-27 | 1987-01-07 | デイスコビジョン アソシエイツ | Electric signal storage |
US4647258A (en) * | 1984-10-19 | 1987-03-03 | Massarsch Karl R | Arrangement in vibration isolation or vibration damping |
US4751757A (en) * | 1986-05-09 | 1988-06-21 | American Thermo Seal, Inc. | Wave dampening device for use in a water bed |
JPH0288669A (en) * | 1988-09-27 | 1990-03-28 | Asahi Chem Ind Co Ltd | Flame-retardant resin composition |
US4974397A (en) * | 1989-10-16 | 1990-12-04 | Jim Ricken | Anti-stress saddle pad for horses |
US5121962A (en) * | 1989-10-13 | 1992-06-16 | Spenco Medical Corporation | Cushion for absorbing shock damping vibration and distributing pressure |
US5179747A (en) * | 1992-02-14 | 1993-01-19 | Zink Robert C | Pillow radio apparatus |
JPH0724937A (en) * | 1993-07-07 | 1995-01-27 | Asahi Corp | Molding method of shoes having shock-absorbing characteristics |
JPH0732511A (en) * | 1993-07-20 | 1995-02-03 | Asahi Corp | Molding of shock absorbing shoes |
FR2712600A1 (en) * | 1993-11-18 | 1995-05-24 | Rhone Poulenc Chimie | Anhydrous electro-rheological fluid |
JPH07145287A (en) * | 1993-11-25 | 1995-06-06 | Sekisui Chem Co Ltd | Vinyl chloride-based resin composition |
US5452957A (en) * | 1994-11-22 | 1995-09-26 | Dana Corporation | Center bearing assembly including support member containing rheological fluid |
US5564202A (en) * | 1990-05-24 | 1996-10-15 | Hoppenstein; Reuben | Hydropneumatic support system for footwear |
-
1996
- 1996-12-31 GB GB9812854A patent/GB2324352B/en not_active Expired - Fee Related
Patent Citations (26)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2873963A (en) * | 1954-11-09 | 1959-02-17 | Paul H Taylor | Liquid spring and oleo suspension for aircraft and vehicles |
US3992002A (en) * | 1975-02-18 | 1976-11-16 | Pitney-Bowes, Inc. | Sheet registering apparatus |
US3990512A (en) * | 1975-07-10 | 1976-11-09 | Ultrasonic Energy Corporation | Method and system for ultrasonic oil recovery |
DE2701181A1 (en) * | 1977-01-13 | 1978-07-20 | Picker | Resilient filling material for suspension unit - comprising suspension of fluid and hollow polymer particles with closed elastic casings (NL 17.7.78) |
FR2384996A1 (en) * | 1977-03-22 | 1978-10-20 | Trenkamp & Gehle | SUSPENSION DEVICE, IN PARTICULAR FOR VEHICLE AXLES |
JPS621139A (en) * | 1978-03-27 | 1987-01-07 | デイスコビジョン アソシエイツ | Electric signal storage |
JPS5516546A (en) * | 1978-07-20 | 1980-02-05 | Matsushita Electric Ind Co Ltd | Dynamic loudspeaker |
DE2841995A1 (en) * | 1978-09-27 | 1980-04-10 | Continental Gummi Werke Ag | Hydropneumatic shock absorber - comprises cellular rubber core with solid skin vulcanised onto it |
FR2534998A1 (en) * | 1982-10-25 | 1984-04-27 | Imp Clevite Inc | DRY VISCOUS ELASTIC SHOCK ABSORBER |
FR2534997A1 (en) * | 1982-10-25 | 1984-04-27 | Imp Clevite Inc | FLEXIBLE WALL ELASTIC SHOCK ABSORBER |
US4560042A (en) * | 1984-04-30 | 1985-12-24 | General Motors Corporation | Method of self-pressurizing a damper |
US4566565A (en) * | 1984-04-30 | 1986-01-28 | General Motors Corporation | Self-pressurized damper |
US4647258A (en) * | 1984-10-19 | 1987-03-03 | Massarsch Karl R | Arrangement in vibration isolation or vibration damping |
US4607586A (en) * | 1985-03-25 | 1986-08-26 | Taquino Weldon P | Preloaded compression absorber cell for boat bumpers |
US4751757A (en) * | 1986-05-09 | 1988-06-21 | American Thermo Seal, Inc. | Wave dampening device for use in a water bed |
JPH0288669A (en) * | 1988-09-27 | 1990-03-28 | Asahi Chem Ind Co Ltd | Flame-retardant resin composition |
US5330249A (en) * | 1989-10-13 | 1994-07-19 | Spenco Medical Corporation | Cushion for absorbing shock, damping vibration and distributing pressure |
US5121962A (en) * | 1989-10-13 | 1992-06-16 | Spenco Medical Corporation | Cushion for absorbing shock damping vibration and distributing pressure |
US4974397A (en) * | 1989-10-16 | 1990-12-04 | Jim Ricken | Anti-stress saddle pad for horses |
US5564202A (en) * | 1990-05-24 | 1996-10-15 | Hoppenstein; Reuben | Hydropneumatic support system for footwear |
US5179747A (en) * | 1992-02-14 | 1993-01-19 | Zink Robert C | Pillow radio apparatus |
JPH0724937A (en) * | 1993-07-07 | 1995-01-27 | Asahi Corp | Molding method of shoes having shock-absorbing characteristics |
JPH0732511A (en) * | 1993-07-20 | 1995-02-03 | Asahi Corp | Molding of shock absorbing shoes |
FR2712600A1 (en) * | 1993-11-18 | 1995-05-24 | Rhone Poulenc Chimie | Anhydrous electro-rheological fluid |
JPH07145287A (en) * | 1993-11-25 | 1995-06-06 | Sekisui Chem Co Ltd | Vinyl chloride-based resin composition |
US5452957A (en) * | 1994-11-22 | 1995-09-26 | Dana Corporation | Center bearing assembly including support member containing rheological fluid |
Non-Patent Citations (6)
Title |
---|
PATENT ABS OF JAP vol 014 no 284(C-0730)20 JUN 90 & JP 02 088 669 A(ASAHI CHEM IND CO LTD) 28 MARCH 90 * |
PATENT ABS OF JAP vol 095 no 004 31 MAY 95 & JP 07 024 937 A (ASAHI CORP) 27 JANUARY 1995 * |
PATENT ABS OF JAP vol 095 no 005 30 JUN 95 & JP 07 032 511 A (ASAHI CORP) 3 FEBRUARY 1995 * |
PATENT ABS OF JAP vol.011 no 333 (M-637)30 OCT 87 & JP 62 001 139 A(CHUGOKU RUBBER KOGYO KK ) 25 MAY 87 * |
PATENT ABS OF JAP vol.095 no 009 31 OCT 95 & JP 07 145 287 A (SEKISUI CHEM CO LTD) 6 JUNE 1995 * |
PATENT ABS OF JAP vol004 no 044(E-005) 5 APR 80 & JP 55 016 546 A (MATSUSHITA ELECTRIC IND CO LTD)5 FEB 80 * |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2002021013A1 (en) | 2000-09-06 | 2002-03-14 | William Alexander Courtney | Fluid filled impact absorber |
US9056983B2 (en) | 2011-09-09 | 2015-06-16 | Purdue Research Foundation | Dynamic load-absorbing materials and articles |
US9394959B2 (en) | 2011-09-09 | 2016-07-19 | Purdue Research Foundation | Dynamic load-absorbing material and articles |
US9839250B2 (en) | 2011-09-09 | 2017-12-12 | Purdue Research Foundation | Dynamic load-absorbing materials and articles |
US10183423B2 (en) | 2011-09-09 | 2019-01-22 | Purdue Research Foundation | Method of making a blast or shock wave mitigating material |
Also Published As
Publication number | Publication date |
---|---|
GB2324352B (en) | 1999-10-20 |
GB9812854D0 (en) | 1998-08-12 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
WO1997025551A3 (en) | Device incorporating elastic fluids and viscous damping | |
AU761074B2 (en) | Damper with high dissipating power | |
Wu et al. | A semi-active control policy to reduce the occurrence and severity of end-stop impacts in a suspension seat with an electrorheological fluid damper | |
KR950002557B1 (en) | Air spring | |
KR920703355A (en) | Car suspension | |
PL320113A1 (en) | Shock absorbing device employing hydrostatic compression of elastomer | |
KR880007269A (en) | Dampers for fluid suspension springs and vehicle suspension systems | |
GB2242957A (en) | Hydraulic damping bushing | |
AP2001002336A0 (en) | A combination of a chamber and a piston, a pump, a motor, a shock absorber and a transducer incorporating the combination. | |
ES2179705A1 (en) | Controllable vibration damper for motor vehicles | |
US20070137415A1 (en) | Vibration-Cushioned Vehicle Steering Wheel | |
GB2324352A (en) | Device incorporating elastic fluids and viscous damping | |
CN100422590C (en) | Booster to adapt air spring pressure for FDD shock absorber | |
US5083756A (en) | Load support vibration isolation mount | |
EP0819866A3 (en) | Vibration damper having oscillating force generating means | |
ATE171253T1 (en) | SHOCK ABSORBER | |
ES2120821A1 (en) | Hydraulically damping elastic bearing | |
GB1424772A (en) | Energy absorber | |
SE9601636L (en) | wave energy converters | |
SE8304636L (en) | HYDRAULIC DUMP, ELASTIC STOCK, SPECIAL FOR DRIVER ENGINE IN MOTOR VEHICLE | |
DK0979190T3 (en) | Motorbogie for traction vehicles | |
EP1092891A3 (en) | A brace bush | |
ES2059248A2 (en) | Telescopic hydropneumatic suspension element particularly for a motor vehicle | |
RU2309307C1 (en) | Method for absorbing of impact energy using heterogeneous system | |
KR960004141A (en) | Shock Absorber of Automotive Steering System |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 20121231 |