Patents-Review.com
ClassID:

143584 ⎘

F04C18/126 - CPC Classification

Classification description:

Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type with radially from the rotor body extending elements, not necessarily co-operating with corresponding recesses in the other rotor, e.g. lobes, Roots type

Recent Application in this class:
#1
20260016012
2026-01-15

Vacuum Pump Assembly with Improved Process By-product Holding Capacity

 #2
20250354555
2025-11-20

SUPERCHARGER ROTORS FOR INCREASED ENGINE POWER OUTPUT

 #3
20250297609
2025-09-25

REAR DRIVE EGR PUMP

 #4
20250257730
2025-08-14

OPTIMIZED ENERGY RECOVERY DEVICE

 #5
20250146490
2025-05-08

Parallel connected multiple shaft roots vacuum pump

 #6
20250092873
2025-03-20

LOW COEFFICIENT OF EXPANSION ROTORS FOR VACUUM BOOSTERS

 #7
20250052241
2025-02-13

VACUUM PUMP WITH REDUCED SEAL REQUIREMENTS

 #8
20240384718
2024-11-21

POSITIVE DISPLACEMENT ROOTS BLOWER NOISE SUPPRESSION

 #9
20240376893
2024-11-14

VOLUMETRIC LOBE COMPRESSOR FOR AN EQUIPMENT AND/OR A SUCTION COMPRESSION PLANT OF MATERIAL IN LIQUID, GASEOUS, SOLID, POWDER, OR SLURRY FORM

 #10
20240328417
2024-10-03

Vacuum system having condenser and root vacuum pump set

 #11
20240234758
2024-07-11

RECIRCULATION GAS FLOW CONTROL AND DISTRIBUTION MODULE FOR FUEL CELLS

 #12
20240218877
2024-07-04

STATOR FOR A VACUUM PUMP

 #13
20240209856
2024-06-27

SUPERCHARGER ROTORS FOR INCREASED ENGINE POWER OUTPUT

 #14
20240035472
2024-02-01

METHOD FOR STOPPING A VACUUM PUMP

 #15
20240003319
2024-01-04

EGR pump locking mechanism and method to lock EGR pump rotating group during engine braking

 #16
20230392598
2023-12-07

Screw compressor and screw rotor

 #17
20230374958
2023-11-23

EGR pump system and control method of EGR pump

 #18
20230323878
2023-10-12

DRY VACUUM PUMP AND MANUFACTURING METHOD

 #19
20230304497
2023-09-28

Roots pump containing rotors that capture and discharge a foreign substance

 #20
20230265849
2023-08-24

Low coefficient of expansion rotors for vacuum boosters

 #21
20230258179
2023-08-17

REAR DRIVE EGR PUMP

 #22
20230167822
2023-06-01

VACUUM SYSTEM HAVING CONDENSER AND ROOT VACUUM PUMP SET

 #23
20230143219
2023-05-11

Dry vacuum pump

 #24
20230096279
2023-03-30

VACUUM SYSTEM HAVING CONDENSER AND ROOT VACUUM PUMP SET

 #25
20230076739
2023-03-09

Multiple stage vacuum pump

 #26
20230033204
2023-02-02

DRY VACUUM PUMP

 #27
20230003208
2023-01-05

Redundant pumping system and pumping method by means of this pumping system

 #28
20220412361
2022-12-29

Vacuum pump cooler for cooling a pumped fluid in a multistage vacuum pump

 #29
20220389930
2022-12-08

Multi-stage pump apparatus including sealing member

 #30
20220372981
2022-11-24

SENSOR ASSEMBLY

 #31
20220299030
2022-09-22

Pump unit

 #32
20220213852
2022-07-07

EGR pump system with overhung rotors

 #33
20220186728
2022-06-16

Electric pump

 #34
20220145886
2022-05-12

Dry pump for gas and set of a plurality of dry pumps for gas

 #35
20220145885
2022-05-12

Positive displacement roots blower noise suppression

 #36
20220127962
2022-04-28

Multistage pump body and multistage gas pump

 #37
20220120279
2022-04-21

ROUGH-VACUUM PUMP OF DRY TYPE

 #38
20220074413
2022-03-10

Non-lubricated system with abradable sealing element, corresponding sealing element and method for assembling the system

 #39
20210381509
2021-12-09

Pumping unit including a rough vacuum pump and a roots vacuum pump

 #40
20210372404
2021-12-02

Power saving vacuuming pump system based on complete-bearing-sealing and dry-large-pressure-difference root vacuuming root pumps

 #41
20210340979
2021-11-04

Roots pump having a seal member with first and second projections

 #42
20210301824
2021-09-30

POWER SAVING VACUUM MACHINE FOR IMPROVING VACUUM ABILITY OF CONDENSER OF THERMAL POWER GENERATOR

 #43
20210277900
2021-09-09

Dry vacuum pump and method for controlling a synchronous motor of a vacuum pump

 #44
20210270265
2021-09-02

Low coefficient of expansion rotors for vacuum boosters

 #45
20210108639
2021-04-15

ROOTS ROTOR FOR REMOVING DUST COAGULUM AND DROPLETS

 #46
20210108638
2021-04-15

Dry vacuum pump with a pressure variation reducing expansion device between a pumping side volume and an oil sump

 #47
20210088049
2021-03-25

VACUUM PUMP SYSTEM

 #48
20210088044
2021-03-25

Driving structure of three-axis multi-stage roots pump

 #49
20210079914
2021-03-18

Multi-stage vacuum pump and a method of differentially pumping multiple vacuum chambers

 #50
20210078741
2021-03-18

Large industrial vacuum sealer system

 #51
20210071667
2021-03-11

EGR pump system and control method of EGR pump

 #52
20210071664
2021-03-11

EGR pump system and control method of EGR pump

 #53
20210054843
2021-02-25

Dry vacuum pump with at least one sealing device with a deflector

 #54
20210054841
2021-02-25

Multi-stage dry roots vacuum pump

 #55
20210031382
2021-02-04

Suction hand and industrial robot provided with the same

 #56
20210025388
2021-01-28

Motor-driven roots pump with smooth activation in low-temperature environment

 #57
20210017991
2021-01-21

CARTRIDGE STYLE FRONT COVER AND COUPLING CAVITY SLEEVE FOR AUTOMOTIVE SUPERCHARGER

 #58
20200408139
2020-12-31

Supercharger integral resonator

 #59
20200208635
2020-07-02

Fluid machine

 #60
20200208633
2020-07-02

Volumetric compressor with lubricant collection device

 #61
20200200178
2020-06-25

Vacuum pump with noise attenuating passage

 #62
20200191147
2020-06-18

Pumping unit and use

 #63
20200173444
2020-06-04

Temperature control of a pumped gas flow

 #64
20200173441
2020-06-04

METHOD FOR MONITORING AN OPERATING STATE OF A PUMPING DEVICE

 #65
20200124050
2020-04-23

Twin-shaft pumps with thermal breaks

 #66
20200116148
2020-04-16

TWIN ROTOR DEVICES WITH INTERNAL CLEARANCES REDUCED BY A COATING AFTER ASSEMBLY, A COATING SYSTEM, AND METHODS

 #67
20200102958
2020-04-02

Twin shaft pumps and a method of pumping

 #68
20200080558
2020-03-12

Inlet port configuration for roots-type supercharger

 #69
20200056613
2020-02-20

External Lobe Rotary Compressor, Expander, or Engine

 #70
20200040895
2020-02-06

MULTISTAGE POWER SAVING VACUUM DEVICE WITH ROOT VACUUM PUMP IN FIRST STAGE

 #71
20190383287
2019-12-19

Optimized helix angle rotors for roots-style supercharger

 #72
20190376516
2019-12-12

Offset stator bores for pump sealing

 #73
20190376515
2019-12-12

Multi-stage rotary lobe pump

 #74
20190368487
2019-12-05

Multi-stage vacuum booster pump rotor

 #75
20190368354
2019-12-05

MULTI-STAGE VACUUM BOOSTER PUMP COUPLING

 #76
20190360533
2019-11-28

Elastomer series coupling damper for supercharger

 #77
20190360487
2019-11-28

Multi-stage vacuum booster pump coupling

 #78
20190277286
2019-09-12

STATOR, ROTARY SHAFT, DRY VACUUM PUMP AND ASSOCIATED MANUFACTURING PROCESSES

 #79
20190226480
2019-07-25

Motor-driven roots pump

 #80
20190195225
2019-06-27

ROTARY BLOWER

 #81
20190186493
2019-06-20

DRY-COMPRESSING VACUUM PUMP

 #82
20190136859
2019-05-09

SIMPLIFIED ROOTS-TYPE BLOWER

 #83
20190113036
2019-04-18

Vacuum pump having a silencer

 #84
20190048872
2019-02-14

Rotary piston pump with a piston formed by a plurality of plates filled with polymer material

 #85
20190032660
2019-01-31

Rotor for a positive displacement compressor

 #86
20180306191
2018-10-25

SUPERCHARGER INLET PANELS

 #87
20180306190
2018-10-25

DAMPENER FOR A FLUID ACCELERATOR SUCH AS A PNEUMATIC BLOWER

 #88
20180283378
2018-10-04

HYDROGEN CIRCULATION PUMP FOR FUEL CELL

 #89
20180252153
2018-09-06

Intake air boost system for two-cycle engine having roots blowers

 #90
20180230999
2018-08-16

Volumetric lobe compressor for equipment collecting waste material

 #91
20180202444
2018-07-19

PRESS FIT TIMING GEAR HAVING WEB CONFIGURATION AND INSERT MOLDED COUPLING FOR SUPERCHARGER

 #92
20180171865
2018-06-21

SUPERCHARGER INTEGRAL RESONATOR

 #93
20180149156
2018-05-31

Modularized integrated non-coaxial multiple chamber dry vacuum pump

 #94
20180135627
2018-05-17

Fluid working systems

 #95
20180100544
2018-04-12

BEARING PLATE FOR SUPERCHARGER

 #96
20180100506
2018-04-12

SUPERCHARGER HAVING ROTOR WITH PRESS-FIT STUB SHAFTS

 #97
20180100430
2018-04-12

SUPERCHARGER HAVING CONSTANT LEAD HELIX ANGLE TIMING GEARS

 #98
20180085799
2018-03-29

Exhaust system, semiconductor manufacturing equipment, and method for operating the exhaust system

 #99
20180073508
2018-03-15

Preloaded Bearing

 #100
20180038375
2018-02-08

Adaptor and vacuum pump

 #101
20180023572
2018-01-25

Device for conditioning flow of working fluids

 #102
20170298733
2017-10-19

COMPOSITE MOLDED ROTARY COMPONENT

 #103
20170274728
2017-09-28

MOTOR-DRIVEN COMPRESSOR AND COOLING SYSTEM

 #104
20170260981
2017-09-14

SEGMENTED ROTOR FORM FOR SUPERCHARGERS AND EXPANDERS

 #105
20170254330
2017-09-07

Volumetric compressor

 #106
20170227010
2017-08-10

Cartridge style front cover and coupling cavity sleeve for automotive supercharger

 #107
20170204881
2017-07-20

Supercharger outlet resonator

 #108
20170204860
2017-07-20

Dry pump and exhaust gas treatment method

 #109
20170204859
2017-07-20

VACUUM PUMP

 #110
20170204858
2017-07-20

VACUUM PUMP

 #111
20170167362
2017-06-15

Thermal abatement systems

 #112
20170146012
2017-05-25

Twin rotor devices with internal clearances reduced by a coating after assembly, a coating system, and methods

 #113
20170122319
2017-05-04

Vacuum pump system

 #114
20170101989
2017-04-13

METHODS FOR MAKING A LOW INERTIA LAMINATED ROTOR

 #115
20170089337
2017-03-30

Arrangement for specifying a pressure

 #116
20170067464
2017-03-09

Optimized helix angle rotors for roots-style supercharger

 #117
20170009643
2017-01-12

Supercharger system for motorized vehicles and related transportation

 #118
20160377303
2016-12-29

High efficiency air delivery system and method

 #119
20160369804
2016-12-22

Suction/compression assembly for a waste material aspiration system

 #120
20160369800
2016-12-22

Suction/compression assembly for a waste material intake equipment or system

 #121
20160356318
2016-12-08

Elastomer series coupling damper for supercharger

 #122
20160339825
2016-11-24

Blower drive system for a vacuum truck

 #123
20160327038
2016-11-10

Fluid working systems

 #124
20160319817
2016-11-03

METHOD OF OPTIMIZING SUPERCHARGER PERFORMANCE

 #125
20160265532
2016-09-15

VACUUM PUMP

 #126
20160245287
2016-08-25

NOISE AND SHOCK REDUCTION IN ROTARY POSITIVE DISPLACEMENT BLOWERS

 #127
20160237885
2016-08-18

SUPERCHARGER HAVING PRE-BOOSTING CONFIGURATION

 #128
20160222966
2016-08-04

Supercharger having integrated clutch and torsional damper

 #129
20160097390
2016-04-07

Vacuum pump rotor for a vacuum pump having a roots pumping mechanism

 #130
20160047340
2016-02-18

Thermal abatement systems

 #131
20160003254
2016-01-07

NOISE CANCELLATION BY PHASE-MATCHING COMMUNICATING DUCTS OF ROOTS-TYPE BLOWER AND EXPANDER

 #132
20160003251
2016-01-07

Pump device and method for controlling the same

 #133
20160003250
2016-01-07

AXIAL SEAL FOR ROOTS-STYLE SUPERCHARGER

 #134
20160003249
2016-01-07

Supercharger with air vent pathway to engine

 #135
20160003248
2016-01-07

Low inertia laminated rotor

 #136
20160003129
2016-01-07

BEARING PLATE BLEED PORT FOR ROOTS-TYPE SUPERCHARGERS

 #137
20150374950
2015-12-31

Mechanical ventilation system utilizing bias valve

 #138
20150361982
2015-12-17

Shunt pulsation trap for positive-displacement machinery

 #139
20150308430
2015-10-29

Vacuum pump

 #140
20150285248
2015-10-08

ROTARY LOBE PUMP WITH WIPER BLADES

 #141
20150260188
2015-09-17

SUPERCHARGER WITH ALIGNMENT MECHANISM BETWEEN INPUT AND ROTOR SHAFTS

 #142
20150204332
2015-07-23

Pumping unit and method for controlling such a pumping unit

 #143
20150170938
2015-06-18

Method and device for pumping of a process chamber

 #144
20150139845
2015-05-21

Housing for a rotary vane pump

 #145
20150136246
2015-05-21

Flood water removal system

 #146
20150132171
2015-05-14

Roots-style blower with leakage mechanisms

 #147
20150118086
2015-04-30

Optimized helix angle rotors for roots-style supercharger

 #148
20150114289
2015-04-30

Coating equipment for a composite membrane without a diffusion pump and its thickness gauge for both thick and thin coatings

 #149
20150050091
2015-02-19

Method and apparatus for treating the outlet air of a pneumatic waste conveying system

 #150
20150037187
2015-02-05

Pump

 #151
20150023811
2015-01-22

Compressor

 #152
20140286806
2014-09-25

Multi-stage vacuum pump

 #153
20140205483
2014-07-24

Roots pump connection channels separating adjacent pump stages

 #154
20140112815
2014-04-24

VACUUM PUMP

 #155
20140112814
2014-04-24

VACUUM PUMP

 #156
20140079581
2014-03-20

ROTOR FOR PUMP

 #157
20130294957
2013-11-07

Pump enveloped with thermally conductive material

 #158
20130283595
2013-10-31

Roots-type blower rotor alignment method

 #159
20130280062
2013-10-24

Coupling structure for vacuum exhaust device and vacuum exhaust system

 #160
20130146035
2013-06-13

Air supply system with two-stage roots blower

 #161
20120255445
2012-10-11

Double vacuum pump apparatus, gas purification system provided with double vacuum pump apparatus, and exhaust gas vibration suppressing device in double vacuum pump apparatus

 #162
20120201709
2012-08-09

Compressor having intercooler core

 #163
20120195783
2012-08-02

Noise and shock reduction in rotary positive displacement blowers

 #164
20120177526
2012-07-12

Air compressor

 #165
20120171033
2012-07-05

Pump with corrosion resistant shaft and rotor surfaces

 #166
20120134867
2012-05-31

Positive-displacement dry pump

 #167
20120121442
2012-05-17

Multistage dry vacuum pump

 #168
20120045322
2012-02-23

VACUUM PUMP

 #169
20120014825
2012-01-19

Roots fluid machine with reduced gas leakage

 #170
20110318210
2011-12-29

Multistage roots vacuum pump having different tip radius and meshing clearance from inlet stage to exhaust stage

 #171
20110300014
2011-12-08

Rotary lobe blower (pump) or vacuum pump with a shunt pulsation trap

 #172
20110239995
2011-10-06

BLOWER RETROFIT AND METHOD TO IMPROVE DIESEL LOCOMOTIVE PERFORMANCE

 #173
20110150671
2011-06-23

Supercharger timing gear oil pump

 #174
20110142687
2011-06-16

Flood water removal system

 #175
20110129374
2011-06-02

Vacuum pump in particular roots type pump

 #176
20110088697
2011-04-21

Mechanical ventilation system utilizing bias valve

 #177
20110061538
2011-03-17

Method of altering a fluid-borne contaminant

 #178
20110058974
2011-03-10

Optimized helix angle rotors for roots-style supercharger

 #179
20100269798
2010-10-28

Integral rotor noise attenuators

 #180
20100269797
2010-10-28

Tuning device with combined backflow function

 #181
20100266433
2010-10-21

Multi-stage dry pump

 #182
20100254846
2010-10-07

Roots type fluid machine

 #183
20100239448
2010-09-23

FKM OR FFKM MULTIPLE LAYERS SEAL

 #184
20100226808
2010-09-09

Multi stage, clam shell vacuum pump

 #185
20100209259
2010-08-19

EVACUATION APPARATUS

 #186
20100202912
2010-08-12

Apparatus for cleaning rotation body and vacuum pump having the same

 #187
20100178187
2010-07-15

VACUUM PUMP

 #188
20100172782
2010-07-08

Vacuum pump

 #189
20100158728
2010-06-24

Vacuum pump

 #190
20100150760
2010-06-17

ROTARY VACUUM PUMP

 #191
20100119399
2010-05-13

Vacuum pump

 #192
20100111736
2010-05-06

Roots-type blower rotor alignment apparatus

 #193
20100108040
2010-05-06

Supercharger system for motorized vehicles and related transportation

 #194
20100104464
2010-04-29

Roots pumps

 #195
20100047104
2010-02-25

Fluid machine with divided housing

 #196
20090311113
2009-12-17

Rotor assembly for multi-stage pump

 #197
20090311105
2009-12-17

Rotary meter flexible edge impeller assembly

 #198
20090269231
2009-10-29

Method of Pumping Gas

 #199
20090246040
2009-10-01

Multistage vacuum pump unit and an operation method thereof

 #200
20090232691
2009-09-17

Low-pressure screw compressor

 #201
20090220371
2009-09-03

METHODS FOR DIMENSIONAL RESTORATION OF ROOTS TYPE BLOWER ROTORS, RESTORED ROTORS, AND APPARATUS HAVING RESTORED ROTOR

 #202
20090148331
2009-06-11

Roots type gear compressor with helical lobes having feedback cavity

 #203
20090148330
2009-06-11

Optimized helix angle rotors for Roots-style supercharger

 #204
20090142213
2009-06-04

Roots-type blower reduced acoustic signature method and apparatus

 #205
20090142212
2009-06-04

Rotary blower with noise abatement jacket enclosure

 #206
20090114047
2009-05-07

Gear Assembly

 #207
20090110583
2009-04-30

Rotary blower with super-charged injection cooling

 #208
20090097984
2009-04-16

Operation control device for vacuum pump and method for stopping operation thereof

 #209
20090047163
2009-02-19

Roots type pump and fuel cell system

 #210
20090035151
2009-02-05

Vacuum pump self-diagnosis method, vacuum pump self-diagnosis system, and vacuum pump central monitoring system

 #211
20090004039
2009-01-01

Single stage root type-vacuum pump and vacuum fluid transport system employing the single stage root type-vacuum pump

 #212
20080310987
2008-12-18

Rotary piston machine

 #213
20080304981
2008-12-11

Motor direct drive air pump and related applications thereof

 #214
20080292487
2008-11-27

Tapered rotor assemblies for a supercharger

 #215
20080292486
2008-11-27

Rotary blower with corrosion-resistant abradable coating

 #216
20080292452
2008-11-27

Housing for a supercharger assembly

 #217
20080226485
2008-09-18

Vacuum pump having rotation body cleaning unit with spraying holes on an output surface of the cleaning body surrounding a shaft

 #218
20080181803
2008-07-31

Reflux gas compressor

 #219
20080175739
2008-07-24

SUPERCHARGER WITH HEAT INSULATED GEAR CASE

 #220
20080170958
2008-07-17

ROTOR ASSEMBLY AND METHOD OF FORMING

 #221
20080159889
2008-07-03

FLOOD WATER REMOVAL SYSTEM

 #222
20080149452
2008-06-26

Torsion damping mechanism for a supercharger

 #223
20080131302
2008-06-05

OIL-FREE FLUID MACHINE HAVING TWO OR MORE ROTORS

 #224
20080118383
2008-05-22

Vacuum pump having fluid port and exhaust system

 #225
20080107550
2008-05-08

ELETRIC PUMP

 #226
20080080984
2008-04-03

EVACUATION APPARATUS

 #227
20080080982
2008-04-03

EVACUATION APPARATUS

 #228
20080063536
2008-03-13

Method of controlling the stopping operation of vacuum pump and device therefor

 #229
20080060623
2008-03-13

SUPERCHARGER WITH GEAR CASE COOLING FAN

 #230
20080060622
2008-03-13

Supercharger with housing internal noise attenuation

 #231
20080053438
2008-03-06

Portable ventilator system

 #232
20080044275
2008-02-21

PUMP

 #233
20080025858
2008-01-31

Composite dry vacuum pump having roots and screw rotor

 #234
20070286749
2007-12-13

Drive for vacuum pump

 #235
20070274851
2007-11-29

Lubricating system for a rotary compressor

 #236
20070224065
2007-09-27

Coat Pump Assembly

 #237
20070217939
2007-09-20

GAS-COMPRESSION MODULE FOR A FUEL CELL

 #238
20070177999
2007-08-02

Electric pump for hydrogen circulation

 #239
20070172361
2007-07-26

Cleaning method of a rotary piston vacuum pump

 #240
20070163589
2007-07-19

Portable ventilator system

 #241
20070148030
2007-06-28

Roots type fluid machine

 #242
20070104587
2007-05-10

Evacuation apparatus

 #243
20070048162
2007-03-01

Multistage roots-type vacuum pump

 #244
20070020111
2007-01-25

Fast enclosure pumping with power saving

 #245
20070000490
2007-01-04

Portable ventilator system

 #246
20060263230
2006-11-23

Optimized helix angle rotors for Roots-style supercharger

 #247
20060249153
2006-11-09

Mechanical ventilation system utilizing bias valve

 #248
20060222506
2006-10-05

Rapidly pumping out an enclosure while limiting energy consumption

 #249
20060216186
2006-09-28

Seal assemblies

 #250
20060213518
2006-09-28

Portable ventilator system

 #251
20060198735
2006-09-07

Vacuum pump and method of starting the same

 #252
20060120909
2006-06-08

Rotary piston vacuum pump with washing installation

 #253
20060088427
2006-04-27

Roots compressor

 #254
20060083651
2006-04-20

Composite dry vacuum pump having roots rotor and screw rotor

 #255
20060067835
2006-03-30

Rotary compressor and method of operating a rotary compressor

 #256
20060029510
2006-02-09

Motor-driven Roots compressor

 #257
20050276713
2005-12-15

Twin-shaft vacuum pump and method of forming same

 #258
20050232791
2005-10-20

Dual-shaft vacuum pump

 #259
20050166921
2005-08-04

Method and apparatus for attenuating compressor noise

 #260
20050123414
2005-06-09

Pumping apparatus

 #261
20050118035
2005-06-02

Multistage dry vacuum pump

 #262
20050112013
2005-05-26

Method and apparatus for reducing noise in a roots-type blower

 #263
20050110446
2005-05-26

System and method for starting pump

 #264
20050089424
2005-04-28

Multi-stage vacuum pump

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2005-04-21

Regenerative compressor motor control for a fuel cell power system

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Multistage dry pump

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Portable ventilator system

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Connecting ring of a root vacuum pump

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Rotary lobe blower or vacuum pump with synchronized induction and discharge flows (SIDF)

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Compressor formed by identical rotors with circular arcs

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18197743
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Oil box device of a roots vacuum pump with a crossed cooling water tube set

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17563070
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Complete bearing-sealed root vacuum pump system capable of promoting vacuum ability of condenser of power plant