US20140099226A1 - Simplified roots-type blower - Google Patents

Simplified roots-type blower Download PDF

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Publication number
US20140099226A1
US20140099226A1 US14/094,044 US201314094044A US2014099226A1 US 20140099226 A1 US20140099226 A1 US 20140099226A1 US 201314094044 A US201314094044 A US 201314094044A US 2014099226 A1 US2014099226 A1 US 2014099226A1
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United States
Prior art keywords
rotor
roots
housing
bearing
type blower
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.)
Abandoned
Application number
US14/094,044
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English (en)
Inventor
William Nicholas Eybergen
Kelly Ann WILLIAMS
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Eaton Intelligent Power Ltd
Original Assignee
Eaton Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Eaton Corp filed Critical Eaton Corp
Priority to US14/094,044 priority Critical patent/US20140099226A1/en
Publication of US20140099226A1 publication Critical patent/US20140099226A1/en
Priority to US16/028,097 priority patent/US20190136859A1/en
Assigned to EATON INTELLIGENT POWER LIMITED reassignment EATON INTELLIGENT POWER LIMITED ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: EATON CORPORATION
Abandoned legal-status Critical Current

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C2/00—Rotary-piston machines or pumps
    • F04C2/08—Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing
    • F04C2/12—Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C29/00—Component parts, details or accessories of pumps or pumping installations, not provided for in groups F04C18/00 - F04C28/00
    • F04C29/06—Silencing
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C18/00—Rotary-piston pumps specially adapted for elastic fluids
    • F04C18/08—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
    • F04C18/082—Details specially related to intermeshing engagement type pumps
    • F04C18/086—Carter
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C18/00—Rotary-piston pumps specially adapted for elastic fluids
    • F04C18/08—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
    • F04C18/12—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
    • F04C18/126—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
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C2/00—Rotary-piston machines or pumps
    • F04C2/08—Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C2/00—Rotary-piston machines or pumps
    • F04C2/08—Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing
    • F04C2/12—Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type
    • F04C2/126—Rotary-piston machines or pumps 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
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C2230/00—Manufacture
    • F04C2230/60—Assembly methods
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C29/00—Component parts, details or accessories of pumps or pumping installations, not provided for in groups F04C18/00 - F04C28/00
    • F04C29/0042—Driving elements, brakes, couplings, transmissions specially adapted for pumps
    • F04C29/005—Means for transmitting movement from the prime mover to driven parts of the pump, e.g. clutches, couplings, transmissions
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05C—INDEXING SCHEME RELATING TO MATERIALS, MATERIAL PROPERTIES OR MATERIAL CHARACTERISTICS FOR MACHINES, ENGINES OR PUMPS OTHER THAN NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES
    • F05C2225/00—Synthetic polymers, e.g. plastics; Rubber
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05C—INDEXING SCHEME RELATING TO MATERIALS, MATERIAL PROPERTIES OR MATERIAL CHARACTERISTICS FOR MACHINES, ENGINES OR PUMPS OTHER THAN NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES
    • F05C2253/00—Other material characteristics; Treatment of material
    • F05C2253/04—Composite, e.g. fibre-reinforced
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49229—Prime mover or fluid pump making
    • Y10T29/49236—Fluid pump or compressor making
    • Y10T29/49242—Screw or gear type, e.g., Moineau type

Definitions

  • the present disclosure relates generally to blowers. More particularly, the present disclosure relates to blowers such as roots-type air blowers.
  • Roots-type air blowers are positive displacement pumps that move air through the use of intermeshing rotors.
  • the rotors are mounted within rotor bores defined by a rotor bore housing.
  • the rotors are typically supported within bearings mounted within a bearing plate assembly that attaches to the rotor bore housing.
  • the bearings function to locate the rotors in the bearing plate and are press-fit into pockets machined in the bearing plate.
  • a relatively high degree of precision is needed to ensure that no contact is made between the rotors or between the rotors and the rotor bore housing.
  • the bearing plate assembly and the rotor bore housing are manufactured from metal using tightly controlled assembly and machining operations.
  • One aspect of the present disclosure relates to a simplified roots-type blower having a molded polymeric rotor bore housing with integrally molded bearing pockets. This type of design eliminates the need for machining.
  • a roots-type blower having a molded, polymeric rotor bore housing and rotors designed with sharp edges which cut the housing to an exact size during the run-in period at start up thereby improving volumetric and thermal efficiency.
  • the peripheral edges of the rotors cut away portions of the housing defining the rotor bores such that the inner shapes of the rotor bores match the outer shape defined by the peripheral edges of the rotors as the rotors are rotated about their respective axes.
  • at least portions of the rotor bores are intentionally molded slightly undersized to allow the undersized portions of the rotor bores to be cut away by the rotors during the initial run-in period at startup.
  • a further aspect of the present disclosure relates to a roots-type blower molded or otherwise constructed of a polymeric (e.g., plastic) material having dampening properties that assist in reducing timing gear rattle and limiting the amplification of air pulsation related noise.
  • a polymeric (e.g., plastic) material having dampening properties that assist in reducing timing gear rattle and limiting the amplification of air pulsation related noise.
  • the use of dampening plastic materials combined with a design having bearing pockets and rotor bores integrated into the same housing piece can reduce the pulsation noise and gear rattle typical of conventional roots-type blowers.
  • the use of plastic timing gears or the combination of metal (e.g., steel) and plastic timing gears can have a significant impact on reducing gear rattle.
  • a further aspect of the present disclosure relates to a roots-type blower having an injection molded, single-piece housing that includes rotor bores and bearing pockets integrated therein.
  • bearings are molded within the bearing pockets using an insert molding technique.
  • the polymeric material of the housing is reinforced with reinforcing members such as glass fibers.
  • glass fibers are specifically oriented to enhance part precision and structural integrity.
  • the molded, polymeric housing defining the rotor bores and the bearing pockets connects with an inlet housing having a metal construction.
  • an alignment/pilot interface is provided between the metal, inlet housing and the molded, plastic rotor bore housing. The alignment interface can be configured to assist in improving or maintaining concentricity of the rotor bores.
  • the roots-type blower includes rotor bores, rotors rotationally mounted within the rotor bores, rotor timing gears mounted at one end of the roots-type blower and a rotor drive pulley mounted at an opposite end of the roots-type blower.
  • the rotor bores are positioned between the drive pulley and the rotor timing gears.
  • the inlet of the roots-type blower is positioned generally adjacent the second end of the roots-type blower and the outlet of the roots-type blower is positioned generally adjacent to the first end of the roots-type blower.
  • Still another aspect of the present disclosure relates to a roots-type blower including a rotor bore housing having a molded polymeric construction.
  • the rotor bore housing defines a first rotor bore aligned along a first rotor bore axis and a second rotor bore aligned along a second rotor bore axis.
  • the first and second rotor bore axes are parallel.
  • the rotor bore housing also defines a first bearing pocket co-axially aligned with the first rotor bore axis and a second bearing pocket co-axially aligned with the second rotor bore axis.
  • the rotor bore housing further defines a gear chamber.
  • the roots-type blower also includes a first bearing mounted within the first bearing pocket and a second bearing mounted within a second bearing pocket.
  • the roots-type blower further includes a first roots-type rotor having a first rotor shaft aligned along the first rotor bore axis and a second roots-type rotor having a second rotor shaft aligned along the second rotor bore axis.
  • the first rotor shaft is supported by the first bearing such that the first roots-type rotor is free to rotate relative to the rotor bore housing about the first rotor bore axis.
  • the second rotor shaft is supported by the second bearing such that the second roots-type rotor is free to rotate relative to the rotor bore housing about the second rotor bore axis.
  • the roots-type blower further includes first and second gears positioned within the gear chamber.
  • the first gear is coupled to the first rotor shaft and the second gear is coupled to the second rotor shaft.
  • the first and second gears intermesh with one another and are configured for transferring torque between the first and second rotor shafts.
  • the rotor bore housing defines an outlet of the roots-type blower
  • the roots-type blower further includes a metal inlet housing that attaches to the rotor bore housing.
  • the inlet housing defines an inlet of the roots-type blower.
  • a roots-type blower including a rotor bore housing having a fiber reinforced polymeric construction.
  • the rotor bore housing defines a first rotor bore and a second rotor bore.
  • the rotor bore housing also defines a first bearing pocket corresponding to the first rotor bore and a second bearing pocket corresponding to the second rotor bore.
  • the rotor bore housing further defines a gear chamber.
  • the roots-type blower also includes a first bearing mounted within the first bearing pocket and a second bearing mounted within the second bearing pocket.
  • the roots-type blower further includes a first roots-type rotor having a first rotor shaft and a second roots-type rotor having a second rotor shaft.
  • the first roots-type rotor is positioned within the first rotor bore and the second roots-type rotor is positioned within the second rotor bore.
  • the first and second rotor shafts are rotatable about rotor shaft axes that are positioned such that the first and second root-type rotors intermesh as the first and second roots-type rotors rotate.
  • the first rotor shaft is supported within the first bearing and the second rotor shaft is supported by the second bearing.
  • the roots-type blower further includes first and second gears positioned within the gear chamber. The first gear is coupled to the first rotor shaft and the second gear is coupled to the second rotor shaft.
  • the roots-type blower can also include an inlet housing that attaches to the rotor bore housing.
  • the inlet housing can have a metal construction and can define an inlet of the roots-type blower that is in fluid communication with the first and second rotor bores.
  • the rotor bore housing can define an outlet of the roots-type blower that is in fluid communication with the first and second rotor bores.
  • FIG. 1 is a schematic depiction of a prior art roots-type blower
  • FIG. 2 is a front, top perspective view of a roots-type blower in accordance with the principles of the present disclosure
  • FIG. 3 is a rear, top perspective view of the roots-type blower of FIG. 2 ;
  • FIG. 4 is a rear, bottom perspective view of the roots-type blower of FIG. 2 ;
  • FIG. 5 is a front, bottom view of the roots-type blower of FIG. 2 ;
  • FIG. 6 is a top view of the roots-type blower of FIG. 2 ;
  • FIG. 7 is a rear view of the roots-type blower of FIG. 2 ;
  • FIG. 8 is a front view of the roots-type blower of FIG. 2 ;
  • FIG. 9 is a bottom view of the roots-type blower of FIG. 2 ;
  • FIG. 10 is an elevation view of a first side of the roots-type blower of FIG. 2 ;
  • FIG. 11 is an elevation view of a second side of the roots-type blower of FIG. 2 ;
  • FIG. 12 is a cross-sectional view taken along section line 12 - 12 of FIG. 8 ;
  • FIG. 13 is a cross-sectional view taken along section line 13 - 13 of FIG. 8 ;
  • FIG. 14 is a cross-sectional view taken along section line 14 - 14 of FIG. 8 ;
  • FIG. 15 is a top, front perspective view of the roots-type blower of FIG. 2 with an inlet housing of the roots-type blower removed;
  • FIG. 16 is a bottom, rear perspective view of the roots-type blower of FIG. 2 with a gear chamber cover removed;
  • FIG. 17 is a top, front perspective view of a rotor bore housing of the roots-type blower of FIG. 2 ;
  • FIG. 18 is a bottom, rear perspective view of the rotor bore housing of FIG. 17 ;
  • FIG. 19 is a top view of the rotor bore housing of FIG. 17 ;
  • FIG. 20 is a front view of the rotor bore housing of FIG. 17 ;
  • FIG. 21 is a rear view of the rotor bore housing of FIG. 17 ;
  • FIG. 22 is a bottom view of the rotor bore housing of FIG. 17 ;
  • FIG. 23 is an elevation view of a first side of the rotor bore housing of FIG. 17 ;
  • FIG. 24 is an elevation view of a second side of the rotor bore housing of FIG. 17 ;
  • FIG. 25 is a cross-sectional view of the rotor bore housing of FIG. 17 ;
  • FIG. 26 is another cross-sectional view of the rotor bore housing of FIG. 17 ;
  • FIG. 27 is a top, rear perspective view of an inlet housing of the roots-type blower of FIG. 2 ;
  • FIG. 28 is a bottom, front perspective view of the inlet housing of FIG. 27 ;
  • FIG. 29 is a top view of the inlet housing of FIG. 27 ;
  • FIG. 30 is a bottom view of the inlet housing of FIG. 27 ;
  • FIG. 31 is a rear view of the inlet housing of FIG. 27 ;
  • FIG. 32 is a front view of the inlet housing of FIG. 27 ;
  • FIG. 33 is an elevation view of a first side of the inlet housing of FIG. 27 ;
  • FIG. 34 is an elevation view of a second side of the inlet housing of FIG. 27 ;
  • FIG. 35 is a perspective view of the roots-type blower of FIG. 2 ;
  • FIG. 36 shows a roots-type blower embodiment where a protective shield separates the bearings from the rotor bore housing
  • FIG. 37 is a perspective view of the rotor bore housing of FIG. 17 diagrammatically showing a reinforcing fiber orientation scheme for the housing.
  • the present disclosure relates generally to a roots-type blower having a simplified design adapted for providing an improved noise signature.
  • various sides of the depicted embodiments have been designated as top, bottom, front and rear sides. It will be appreciated that such side designations are for convenience only and are not intended to limit how the device may be used. In this regard, it will be appreciated that embodiments in accordance with the principles of the present disclosure can be used in any orientation.
  • FIG. 1 shows a prior art roots-type blower 20 .
  • roots-type blower means a blower having intermeshing rotors that cooperate to move air circumferentially through rotor bores of a rotor housing. As shown at
  • the roots-type blower 20 includes a rotor housing 22 defining first and second rotor bores 24 a , 24 b .
  • the roots-type blower 20 includes an inlet 26 and an outlet 28 that are in fluid communication with the rotor bores 24 a , 24 b .
  • a first rotor 30 a is positioned within the first rotor bore 24 a and a second rotor 30 b is positioned within the second rotor bore 24 b .
  • the rotors 30 a , 30 b each include projections 32 and pockets 34 .
  • the rotors 30 a , 30 b are rotated about their central axes and intermesh with one another.
  • Rotation of the rotors 30 a , 30 is coordinated such that during rotation the projections 32 of the first rotor 30 a are received within the pockets 34 of the second rotor 30 b and the projections 32 of the second rotor 30 b are received within the pockets 34 of the first rotor 30 a .
  • the rotors 30 a , 30 b rotate air from the inlet 26 moves into the pockets 34 and is displaced circumferentially along the rotor bores 24 a , 24 b to the outlet 28 . As shown at FIG.
  • region 38 corresponds to an air intake region where air moves from the inlet 26 into the rotor bore 24 a
  • region 40 corresponds to a region where air is being moved by the rotor 30 b circumferentially along the rotor bore from the inlet 26 toward the outlet 28
  • region 42 represents a region where air within the rotor bore 24 a is being moved from the rotor bore 24 a to the outlet 28 .
  • FIGS. 2-14 illustrate a roots-type blower 50 in accordance with the principles of the present disclosure.
  • the roots-type blower 50 includes a front side 52 , a rear side 54 , a top side 56 , and a bottom side 58 .
  • the front side 52 of the roots-type blower 50 is defined by an inlet housing 60 defining a blower inlet 62 .
  • the inlet 62 is shown facing upward, but could face in other directions (e.g., laterally) as well.
  • the roots-type blower 50 also includes a rotor bore housing 64 that couples to the inlet housing 62 at an alignment interface 66 (see FIGS. 3 , 13 and 14 ).
  • the inlet housing 66 and the rotor bore housing 64 may be coupled together using fasteners or by another connection technique such as adhesive (e.g., ultraviolet light curable adhesive).
  • the rotor bore housing 64 defines a blower outlet 68 positioned at the bottom side 58 of the roots-type blower 50 .
  • the blower outlet 68 is shown facing in a downward direction, but in alternative embodiments could face in other directions as well (e.g., laterally).
  • the roots-type blower 50 also includes a drive pulley 70 and a bearing cap 72 mounted to the inlet housing 60 at the front side of the roots-type blower 50 .
  • a gear chamber cover 74 (see FIGS. 3 and 4 ) is secured to the rotor bore housing 64 at the rear side 54 of the roots-type blower 50 .
  • the roots-type blower 50 also includes a first roots-type rotor 76 and a second roots-type rotor 78 .
  • the first roots-type rotor 76 includes a first rotor shaft 80 aligned along a first rotor shaft axis 82 .
  • the second roots-type rotor 78 includes a second rotor shaft 84 aligned along a second rotor shaft axis 86 .
  • the first and second rotor shaft axes 80 , 82 are preferably parallel.
  • the first and second roots-type rotors 76 , 78 are respectively positioned within first and second rotor bores 88 , 90 defined by the rotor bore housing 64 .
  • first and second rotor bores 88 , 90 are preferably cylindrical.
  • the first rotor bore 88 includes a first cylindrical portion 92 (see FIGS. 14 and 20 ) having a radius of curvature generally centered on the first rotor shaft axis 82 such that the first cylindrical portion 92 curves about the first rotor shaft axis.
  • the second rotor bore 90 includes a second cylindrical portion 94 (see FIGS. 13 and 20 ) having a radius of curvature generally centered on the second rotor shaft axis 86 such that the second cylindrical portion 94 curves about the second rotor shaft axis 82 .
  • the first and second cylindrical portions 92 , 94 preferably define rotor bore axes that are coextensive with the first and second rotor shaft axes 82 , 86 .
  • the first roots-type rotor 76 is configured to rotate within the first rotor bore 88 and the second roots-type rotor 78 is configured to rotate within the second rotor bore 90 .
  • Intermeshing timing gears 96 , 98 (see FIGS. 12 and 16 ) transfer torque between the first and second rotor shafts 80 , 82 and thereby coordinate rotation between the first and second roots-type rotors 76 , 78 .
  • the first timing gear 96 is connected to the rear end of the first rotor shaft 80 by a torque transmitting connection such as a splined connection.
  • the second timing gear 98 is connected to the rear end of the second rotor shaft 86 by a torque transmitting connection such as a splined connection.
  • the first and second timing gears 96 , 98 are positioned within a gear chamber 100 defined by the rotor bore housing 64 .
  • the gear chamber 100 is separated from the first and second rotor bores 98 , 100 by an intermediate divider wall structure 102 of the rotor bore housing 64 .
  • the gear chamber 100 is enclosed by the gear chamber cover 74 which can be removed to access the timing gears 96 , 98 .
  • the gear chamber 100 can contain lubricating oil or grease. Seals 191 (see FIG. 12 ) can be used to prevent lubricating oil from leaking from the gear chamber 100 into the rotor bores 88 , 90 .
  • Torque for rotating the first and second roots-type rotors 76 , 78 can be provided by the drive pulley 70 .
  • the drive pulley 70 can be rotated by a belt driven by the crankshaft of the engine being supercharged.
  • the drive pulley 70 is coupled to the front end of the second rotor shaft 84 by a torque transmitting connection such as a splined connection.
  • the drive pulley 70 is mounted for rotation relative to the inlet housing 60 by a bearing 104 .
  • the bearing 104 mounts on a bearing mounting stub 106 that projects forwardly from the main body of the inlet housing 60 .
  • the bearing 104 allows the drive pulley 70 to rotate relative to the inlet housing 60 about the second rotor shaft axis 86 .
  • the bearing 104 through the drive pulley 70 , also functions to rotationally support the second rotor shaft 84 thereby allowing the second rotor shaft 84 to rotate relative to the inlet housing 60 about the second rotor shaft axis 86 .
  • the splined connection between the pulley 70 and the second rotor shaft 84 allows for relative sliding movement between the drive pulley 70 and the second rotor shaft 84 .
  • the connection can compensate of differences in thermal growth between the shaft 84 and the housing (e.g., the inlet housing and/or the rotor bore housing). Such compensation can help prevent excessive loading of the bearing 104 and/or the bearing 110 .
  • the drive pulley 70 and the timing gears 96 , 98 are positioned at opposite ends/sides of the roots-type blower 50 with the first and second rotor bores 88 , 90 positioned in a region generally between the drive pulley 70 and the timing gears 96 , 98 .
  • the first and second roots-type rotors 76 , 78 are supported for rotation relative to the inlet housing 60 and the rotor bore housing 64 by a relatively simple bearing configuration.
  • the first and second rotor shafts 80 , 84 are supported adjacent there rearward ends by bearings 108 , 110 (see FIG. 12 ).
  • the bearing 108 is mounted within a first bearing pocket 112 defined by the rotor bore housing 64 and the bearing 110 is mounted within a second bearing pocket 114 defined by the rotor bore housing 64 .
  • the bearings 108 , 110 can be press fit within their respective first and second bearing pockets 112 , 114 (see FIG. 12 ).
  • the bearings 108 , 110 can be molded into the first and second bearing pockets 112 , 114 using an insert molding technique or other molding techniques.
  • the bearings 108 , 110 support the rearward ends of the first and second rotor shafts 80 , 84 to permit the shafts 80 , 84 to rotate about their respective axes 82 , 86 relative to the rotor bore housing 64 .
  • the forward end of the first rotor shaft 80 is rotatably supported by a bearing 116 (see FIG. 12 ) mounted within a bearing pocket 118 (see FIG. 12 ) defined by the inlet housing 60 .
  • the bearing pocket 118 is covered by the bearing cap 72 .
  • the forward end of the first rotor shaft 86 is supported for rotation about the second rotor shaft axis 86 by the bearing 104 on which the drive pulley 70 is mounted.
  • the special arrangement of the blower outlet 68 relative to the bearings 108 , 110 and the timing gears 96 , 98 allows for a relatively compact configuration.
  • the rotor bore housing 64 includes a contoured surface 120 (see FIGS. 13 , 20 , 25 and 26 ) that angles downwardly from the first and second rotor bores 88 , 90 to the blower outlet 68 .
  • the contoured surface 120 extends toward the blower outlet 68 , the contoured surface 120 extends directly beneath the bearings 108 , 110 and also directly beneath portions of the timing gears 96 , 98 .
  • the blower outlet 68 at least partially overlaps with the bearings 108 , 112 and the timing gears 96 , 98 in a front-to-rear orientation so as to allow the overall length of the roots-type blower 50 to be relatively compact.
  • the bearings 108 , 110 and the blower outlet 68 are intersected by a reference plane 122 that is perpendicular relative to the first and second rotor shaft axes 82 , 86 .
  • FIGS. 17-26 depict the rotor bore housing 64 from various views.
  • the rotor bore housing 64 has a polymeric construction and is manufactured using a molding process such as an injection molding process.
  • the polymeric construction includes a polymeric material as a base material, and also includes reinforcing elements (e.g., reinforcing fibers such as glass fibers, aramid yarn, carbon fibers, etc.) that help structurally reinforce of the rotor bore housing 64 .
  • Example polymeric base materials include polyethylene terephthalate (PET) and polyamides/nylons such as polyamide (nylon) 66 (PA66), polyamide (nylon) 46 (PA46) and Polyphthalamide (PPA).
  • the entire rotor bore housing 64 is molded as a single, unitary, seamless piece.
  • the rotor bore housing 64 provides a one-piece, seamless, unitary housing that includes both first and second rotor bores 88 , 90 and the corresponding bearing pockets 112 , 114 .
  • a flange 124 is provided at the end of the blower outlet 68 .
  • the outlet passage defines a bell-like curvature 171 that extends to the flange 124 .
  • the rotor bore housing 64 includes an axial projection 126 that projects forwardly from a main body of the rotor bore housing 64 at the front end of the rotor bore housing 64 .
  • the axial projection 126 includes a first cylindrical portion 128 corresponding to the first rotor bore 88 and a second cylindrical portion 130 corresponding to the second rotor bore 90 .
  • the first and second cylindrical portions 128 , 130 meet at an apex 132 .
  • the first and second cylindrical portions 128 , 130 form a generally triangular mid-portion 134 adjacent to the apex 132 .
  • one or more reinforcing members can be molded within the triangular mid-portion to enhance the structural characteristics of the rotor bore housing 64 and to assist in reducing vibrations and associated noise.
  • a plurality of axial ribs 136 are provided on an exterior surface of the main body of the axial projection 126 .
  • the axial ribs 136 are parallel to one another and extend parallel to the first and second rotor shaft axes 82 , 86 .
  • FIGS. 27-34 depict the inlet housing 60 from various views.
  • the inlet housing 60 is constructed of a metal material such as aluminum.
  • the inlet housing 60 is a cast part manufactured from aluminum or other metal.
  • the inlet housing 60 could have a polymeric construction.
  • the inlet housing 60 can be constructed of a polymeric material with reinforcing inserts such as metal inserts for reinforcing the housing at strategic locations. In one embodiment, such insert can be provide for enhancing the ability of the inlet housing 60 to support a belt load applied to the pulley 70 .
  • the inlet housing 60 can be manufactured according to relatively precise tolerances.
  • the inlet housing 60 is constructed of metal and includes a precisely tolerance (e.g., precision machined) piloting receptacle 140 that is sized to receive the axial projection 126 to provide the alignment interface 66 (see FIG. 13 ). Similar to the axial projection 126 , the piloting receptacle 140 has a first cylindrical portion 142 and a second cylindrical portion 144 configured to be concentric with the rotor shaft axes 82 , 86 when the inlet housing 60 is coupled to the rotor bore housing 64 . The piloting receptacle 140 also has a triangular mid-portion 145 .
  • the piloting receptacle 140 is sized to receive and pilot axial projection 126 .
  • the axial projection 126 mates with the piloting receptacle 140
  • contact between the walls of the receptacle 140 and the axial projection 126 forces the axial projection 126 toward a position where the cylindrical portions 128 , 130 are concentric with respect to the first and second rotor shaft axes 82 , 86 .
  • the receptacle 140 provides a pilot function that assists in ensuring the concentricity of the first and second rotor bores 88 , 90 .
  • the inlet housing 60 also includes a piloting projection 147 (see FIGS.
  • the projection 147 has curved portions (e.g., cylindrical portions 147 a , 147 b ) that match the desired curvatures and concentricity of the rotor bores 88 , 90 .
  • the blower inlet 62 is generally rectangular in shape.
  • a contoured, angled surface 150 within the inlet housing 60 positions flow from the blower inlet 62 to the first and second rotor bores 80 , 90 when the inlet housing 60 is mounted to the rotor bore housing 64 .
  • FIG. 35 shows the second roots-type rotor 78 .
  • the depicted roots-type rotor 78 includes projections 200 that project outwardly from the corresponding rotor shaft 80 , 84 .
  • Pockets 202 are defined between the projections 200 .
  • peripheral edges 204 of the projections 200 are sharp so as to function as cutting blades.
  • the rotors 76 , 78 preferably have a metal construction. It will be appreciated that the first roots-type rotor 76 has a similar projection and pocket configuration. It will also be appreciated that other roots-type rotor configurations can be used as well.
  • the rotor bore housing 64 can be molded with the first and second rotor bores 88 , 90 slightly undersized.
  • the roots-type rotors 76 , 78 are mounted within the rotor bores 88 , 90 .
  • the roots-type rotors 76 , 78 are rotated about their respective axes 82 , 86 . As this occurs, the cutting edges of the rotors 76 , 78 cut away portions of the rotor bore housing 64 defining the rotor bores 88 , 90 .
  • This type of cutting process ensures that the inner surfaces of the rotor bores 88 , 90 have a shape that matches the shapes defined by the peripheral edges 204 of the roots-type rotors 76 , 78 as the roots-type rotors 76 , 78 are revolved about their respective axes 82 , 86 .
  • the sharp edges of the rotors 76 , 78 cut the plastic rotor bores to an exact diameter thereby reducing leakage and improving efficiency.
  • the shaft holes of the rotor housing are sized (e.g., molded or shaped with inserts) to be in close proximity to the shafts of the rotors.
  • the shaft holes are sized smaller than bases/roots of the projections/blades of the rotors 76 , 78 on the rotor bore side.
  • the roots-type blower 50 is relatively small and is adapted for use as a supercharger for relatively small engines.
  • the rotor bores 88 , 90 define a combined volume equal to or less than 250 cubic centimeters and the roots-type blower 50 is adapted for use as a supercharger with an engine having a volume of less than one liter, or in the range of 0.6-1.0 liters.
  • aspects of the present disclosure are applicable to larger sized blowers as well.
  • the design is desirable for the design to be configured for inhibiting leakage between the roots-type rotors 76 , 78 and the cylindrical portions 92 , 94 of the rotor bore housing 64 .
  • the rotor bore housing 64 is connected to the inlet housing 60 by an adhesive such as an ultraviolet light curable adhesive.
  • adhesive such as a ultraviolet light curable adhesive.
  • the blower inlet 62 is defined by a metal part in the form of an inlet housing 60
  • the bearings 108 , 110 , the timing gears 96 , 98 and a majority of each of the roots-type rotors 76 , 80 are provided within the rotor bore housing 64 which is preferably polymeric (e.g., plastic).
  • the blower outlet 68 is provided on the polymeric rotor bore housing 64 .
  • the polymeric construction of the rotor bore housing 64 has improved sound deadening and vibration dampening characteristics as compared to metal.
  • the use of the polymeric rotor bore housing 64 can assist in dampening noise created by air rushing through the blower outlet 68 and can also assist in dampening or otherwise inhibiting noise associated with gear rattling.
  • plastic or metal shields 300 are provided between the bearings 108 , 110 and the rotor bore housing 64 .
  • the shields 300 can be cup-shaped with center holes 302 for receiving the rotor shafts 80 , 84 .
  • the shields 300 are depicted having a stepped configuration.
  • the stepped configuration includes a first, second and third annular rings 304 , 306 and 308 at are spaced from one another by radial steps.
  • the first annular rings engage the outer races of the bearings 108 , 110 .
  • the stepped configuration preferably conforms to the shape of a bore within the interior of the rotor bore housing 64 .
  • the third annular rings 308 can be provided between the rotor bore housing 64 and the rotor shafts 80 , 84 to assist in providing a bore sealing surface at the divider wall between the rotor bores 88 , 90 and the gear chamber 100 .
  • the metal shields 300 Prior to injection molding the rotor bore housing 64 , the metal shields 300 are pressed onto the bearings 108 , 110 to prevent plastic from flowing into and contaminating the bearings 108 , 110 during the injection molding process. As shown at FIG. 36 , the seals are pressed within the annular rings 306 and the bearings 108 , 110 are pressed within the annular rings 304 .
  • the injection molding die closes and seals on first faces/sides of the bearings 108 , 110 while the die also closes and seals on the shields 300 on opposite faces/sides of the bearings 108 , 110 preventing plastic from entering the bearings 108 , 110 during the insert molding process.
  • the radial step between the annular rings 304 , 306 can correspond to a race thickness of the bearings.
  • the annular rings 308 can fit closely about the rotor shafts so as to inhibit air from leaking through the shaft bores during operation of the blower.
  • the rotor bore housing 64 preferably has a polymeric construction.
  • reinforcing fibers e.g., aramid fibers, glass fibers, carbon fibers, etc.
  • the rotor bore housing 64 is preferably injection molded taking into consideration an orientation strategy for the reinforcing fibers.
  • the reinforcing fibers are oriented in a generally circumferential orientation along the bearing pockets 112 and 114 (see arrow 400 ) and are oriented in a generally axial orientation (e.g., an orientation generally parallel to the rotor shaft axes 82 , 86 as shown by arrows 402 ) along the first and second rotor bores 88 , 90 .

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Applications Or Details Of Rotary Compressors (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
US14/094,044 2011-06-02 2013-12-02 Simplified roots-type blower Abandoned US20140099226A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
US14/094,044 US20140099226A1 (en) 2011-06-02 2013-12-02 Simplified roots-type blower
US16/028,097 US20190136859A1 (en) 2011-06-02 2018-07-05 Simplified roots-type blower

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US201161492520P 2011-06-02 2011-06-02
PCT/US2012/040736 WO2012167248A2 (fr) 2011-06-02 2012-06-04 Soufflante roots simplifiée
US14/094,044 US20140099226A1 (en) 2011-06-02 2013-12-02 Simplified roots-type blower

Related Parent Applications (1)

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PCT/US2012/040736 Continuation WO2012167248A2 (fr) 2011-06-02 2012-06-04 Soufflante roots simplifiée

Related Child Applications (1)

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US16/028,097 Continuation US20190136859A1 (en) 2011-06-02 2018-07-05 Simplified roots-type blower

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US20140099226A1 true US20140099226A1 (en) 2014-04-10

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US14/094,044 Abandoned US20140099226A1 (en) 2011-06-02 2013-12-02 Simplified roots-type blower
US16/028,097 Abandoned US20190136859A1 (en) 2011-06-02 2018-07-05 Simplified roots-type blower

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US (2) US20140099226A1 (fr)
EP (1) EP2715137B1 (fr)
JP (1) JP6091497B2 (fr)
KR (1) KR20140031326A (fr)
CN (2) CN202732341U (fr)
WO (1) WO2012167248A2 (fr)

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USD745056S1 (en) * 2012-06-04 2015-12-08 Eaton Corporation Blower housing
US9745978B2 (en) 2013-11-18 2017-08-29 Pfeiffer Vacuum Gmbh Housing for a rotary vane pump
US10591039B2 (en) 2012-07-03 2020-03-17 Eaton Intelligent Power Limited Fiber reinforced plenum for limited-slip differential

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EP2715137B1 (fr) * 2011-06-02 2018-03-28 Eaton Corporation Soufflante roots et methode de fabrication
EP2997243A4 (fr) * 2013-03-15 2016-12-14 Eaton Corp Joint axial pour compresseur de suralimentation du style roots
BR112016016908B1 (pt) 2014-01-24 2022-07-19 Eaton Intelligent Power Limited Sistema de fornecimento de ar para uma máquina agrícola e método para resfriar um escape de motor de uma máquina agrícola
WO2015112593A1 (fr) 2014-01-24 2015-07-30 Eaton Corporation Système de refroidissement et système de distribution d'air pour machine agricole
CN110374872A (zh) * 2019-08-28 2019-10-25 南通晨光石墨设备有限公司 风机

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USD745056S1 (en) * 2012-06-04 2015-12-08 Eaton Corporation Blower housing
US10591039B2 (en) 2012-07-03 2020-03-17 Eaton Intelligent Power Limited Fiber reinforced plenum for limited-slip differential
US9745978B2 (en) 2013-11-18 2017-08-29 Pfeiffer Vacuum Gmbh Housing for a rotary vane pump

Also Published As

Publication number Publication date
JP2014519574A (ja) 2014-08-14
WO2012167248A2 (fr) 2012-12-06
EP2715137A2 (fr) 2014-04-09
JP6091497B2 (ja) 2017-03-08
EP2715137B1 (fr) 2018-03-28
CN202732341U (zh) 2013-02-13
WO2012167248A3 (fr) 2013-07-18
KR20140031326A (ko) 2014-03-12
CN102808767B (zh) 2017-09-01
CN102808767A (zh) 2012-12-05
US20190136859A1 (en) 2019-05-09

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STCB Information on status: application discontinuation

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Effective date: 20171231