Assignee
KEYSTONE INT
US·96 granted patents·2,458 citations·filing 1974–1997
Top patents by PatentIndex Score
96 records- 0194US3982725AValve actuatorKEYSTONE INT·Filed 1974·Granted Sep 28, 1976·86 cites·14 claims
- 0292US4169543AAmplitude responsive detectorKEYSTONE INT·Filed 1977·Granted Oct 2, 1979·50 cites·54 claims
- 0391US5036884AMounting means for fluid pressure transmittersKEYSTONE INT·Filed 1990·Granted Aug 6, 1991·67 cites·20 claims
- 0490US5823228AValve manifoldKEYSTONE INT·Filed 1997·Granted Oct 20, 1998·59 cites·9 claims
- 0590US5007330ARotary actuator and seal assembly for use thereinKEYSTONE INT·Filed 1989·Granted Apr 16, 1991·45 cites·23 claims
- 0689US4846212ABleed valve assembly for double block and bleed systemKEYSTONE INT·Filed 1988·Granted Jul 11, 1989·51 cites·20 claims
- 0789US4616803ADeclutchable valve overrideKEYSTONE INT·Filed 1983·Granted Oct 14, 1986·63 cites·12 claims
- 0886US5579800ARotary valve position indicator and methodKEYSTONE INT·Filed 1994·Granted Dec 3, 1996·47 cites·29 claims
- 0985US4079746AValve assembly having adapter meansKEYSTONE INT·Filed 1975·Granted Mar 21, 1978·38 cites·10 claims
- 1084US5590684ADual pilot manifold assembly for a safety relief valveKEYSTONE INT·Filed 1995·Granted Jan 7, 1997·33 cites·27 claims
- 1184US5244183AFugitive emission sealing assemblyKEYSTONE INT·Filed 1991·Granted Sep 14, 1993·55 cites·39 claims
- 1283US5313976ATop entry ball valve and method of assemblyKEYSTONE INT·Filed 1993·Granted May 24, 1994·49 cites·10 claims
- 1382US5469805AHigh visibility valve position indicatorKEYSTONE INT·Filed 1994·Granted Nov 28, 1995·61 cites·18 claims
- 1482US4023432AActuator having universal-type joint assemblyKEYSTONE INT·Filed 1975·Granted May 17, 1977·24 cites·22 claims
- 1581US4399833AValve assemblyKEYSTONE INT·Filed 1982·Granted Aug 23, 1983·35 cites·13 claims
- 1681US4226118ALevel detectorKEYSTONE INT·Filed 1978·Granted Oct 7, 1980·37 cites·42 claims
- 1780US4846225ATransmission assembly for use with double block and bleed systemKEYSTONE INT·Filed 1988·Granted Jul 11, 1989·37 cites·15 claims
- 1880US3985151AValve actuatorKEYSTONE INT·Filed 1975·Granted Oct 12, 1976·51 cites·10 claims
- 1979US5518028AAdjustable magnet carrier for a valve position indicatorKEYSTONE INT·Filed 1994·Granted May 21, 1996·36 cites·26 claims
- 2079US5044257ARotary actuator and method for forming a rotary pistonKEYSTONE INT·Filed 1990·Granted Sep 3, 1991·46 cites·20 claims
- 2178US5054374ARotary actuatorKEYSTONE INT·Filed 1990·Granted Oct 8, 1991·50 cites·9 claims
- 2278US4589281AMaterial level detector and controlKEYSTONE INT·Filed 1984·Granted May 20, 1986·35 cites·43 claims
- 2378US4505290AValve seat assembly and valveKEYSTONE INT·Filed 1983·Granted Mar 19, 1985·31 cites·11 claims
- 2477US5012841APressure reducing and conditioning valvesKEYSTONE INT·Filed 1989·Granted May 7, 1991·46 cites·6 claims
- 2577US4189950AManual control apparatusKEYSTONE INT·Filed 1978·Granted Feb 26, 1980·28 cites·25 claims
- 2676US5494071AMounting system for pressure transmittersKEYSTONE INT·Filed 1994·Granted Feb 27, 1996·30 cites·1 claims
- 2776US5269347AFluid pressure isolator apparatusKEYSTONE INT·Filed 1992·Granted Dec 14, 1993·37 cites·7 claims
- 2876US4570901APositioning assembly for use with rotatable valvesKEYSTONE INT·Filed 1984·Granted Feb 18, 1986·32 cites·14 claims
- 2975US4541612ARotatable shaft assemblyKEYSTONE INT·Filed 1984·Granted Sep 17, 1985·29 cites·9 claims
- 3075US4275867AValve assembly and methodKEYSTONE INT·Filed 1978·Granted Jun 30, 1981·26 cites·15 claims
- 3174USRE34610EMounting means for fluid pressure transmittersKEYSTONE INT·Filed 1992·Granted May 17, 1994·29 cites·20 claims
- 3274US5292155AMethod and apparatus for mounting an instrument assembly on a main flow lineKEYSTONE INT·Filed 1992·Granted Mar 8, 1994·47 cites·11 claims
- 3374US4682758ADisk/stem connection apparatus for butterfly valveKEYSTONE INT·Filed 1986·Granted Jul 28, 1987·30 cites·19 claims
- 3472US4659064AApparatus for fixing the position of a valve element shaft in a boreKEYSTONE INT·Filed 1986·Granted Apr 21, 1987·32 cites·14 claims
- 3571US4280549AApparatus and process for die-castingKEYSTONE INT·Filed 1979·Granted Jul 28, 1981·13 cites·14 claims
- 3670US5005605AConditioning valveKEYSTONE INT·Filed 1989·Granted Apr 9, 1991·31 cites·2 claims
- 3770US4410163AValve seatKEYSTONE INT·Filed 1982·Granted Oct 18, 1983·25 cites·29 claims
- 3870US4222267AMaterial level detector circuitKEYSTONE INT·Filed 1978·Granted Sep 16, 1980·24 cites·47 claims
- 3968US4870989AHigh temperature safety relief systemKEYSTONE INT·Filed 1988·Granted Oct 3, 1989·26 cites·13 claims
- 4068US4711427AApparatus for connecting a valve element to a valve stemKEYSTONE INT·Filed 1986·Granted Dec 8, 1987·25 cites·7 claims
- 4167US4685611AButterfly valve construction having a composite seatKEYSTONE INT·Filed 1986·Granted Aug 11, 1987·32 cites·19 claims
- 4266US4773625ACorrosion-resistant overlay for the edge of butterfly valvesKEYSTONE INT·Filed 1987·Granted Sep 27, 1988·22 cites·21 claims
- 4366US4701938AData systemKEYSTONE INT·Filed 1985·Granted Oct 20, 1987·36 cites·23 claims
- 4465US4457490AHigh temperature valve and seat thereforKEYSTONE INT·Filed 1982·Granted Jul 3, 1984·21 cites·19 claims
- 4565US4080844AManual control apparatusKEYSTONE INT·Filed 1976·Granted Mar 28, 1978·17 cites·18 claims
- 4664US5011116AShock absorbing sealing means for flow control devicesKEYSTONE INT·Filed 1990·Granted Apr 30, 1991·26 cites·30 claims
- 4763US4848397AHigh temperature safety relief systemKEYSTONE INT·Filed 1988·Granted Jul 18, 1989·22 cites·13 claims
- 4863US4413393AMethod of manufacturing a valve assemblyKEYSTONE INT·Filed 1981·Granted Nov 8, 1983·18 cites·13 claims
- 4962US4967783ARecirculation valve with pilot valveKEYSTONE INT·Filed 1990·Granted Nov 6, 1990·29 cites·16 claims
- 5062US4941502ALow pressure recirculation valveKEYSTONE INT·Filed 1989·Granted Jul 17, 1990·33 cites·11 claims
Showing the top 50 of 96 patent records by PatentIndex Score.
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