US3746482A - Pump having discharge baffle means - Google Patents

Pump having discharge baffle means Download PDF

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Publication number
US3746482A
US3746482A US00186864A US3746482DA US3746482A US 3746482 A US3746482 A US 3746482A US 00186864 A US00186864 A US 00186864A US 3746482D A US3746482D A US 3746482DA US 3746482 A US3746482 A US 3746482A
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United States
Prior art keywords
rotor
outlet
pockets
rotary direction
pump according
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Expired - Lifetime
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US00186864A
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English (en)
Inventor
O Luthi
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Improved Machinery Inc
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Improved Machinery Inc
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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
    • F04C3/00—Rotary-piston machines or pumps, with non-parallel axes of movement of co-operating members, e.g. of screw type
    • F04C3/02—Rotary-piston machines or pumps, with non-parallel axes of movement of co-operating members, e.g. of screw type the axes being arranged at an angle of 90 degrees
    • F04C3/04—Rotary-piston machines or pumps, with non-parallel axes of movement of co-operating members, e.g. of screw type the axes being arranged at an angle of 90 degrees of intermeshing engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing

Definitions

  • ABSTRACT [52] US. Cl. 418/201, 418/206 P f h l 51 1111.0. FOlc 1/24 F04C 1/14 F040 17/16 e Y compr'smg at east One 1 [58] m ch 418/19! 195 201 vided with peripheral rotor pockets, wherein baffle 0 ar 4!
  • the present invention relates generally to pumps and more particularly to pumps of the type including one or more rotors provided with peripheral rotor pockets.
  • the pump rotor or rotors are normally continuously rotatably driven at a constant, relatively high speed sufficient to accomodate the highest capacities or high capacity surges that the pumps are expected encounter.
  • the operation of conventional pumps of this type at or near their highest capacities generally is satisfactory; however, during operation at normal or other flow rates substantially lower than their highest capacities, these conventional pumps are subject to heavy vibration and the production of loud, hammering-type noise.
  • An object of the present invention is to provide a new and improved pump of the aforedescribed type which is particularly constructed and arranged to substantially minimize the beforementioned vibration and hammering-type noise.
  • Another object of the invention is to provide a new and improved pump of the type set forth which is particularly constructed and arranged to substantially minimize said vibration and noise in a relatively simple and economical, although highly efficient, manner.
  • Another object is to provide a new and improved pump of the type set forth which is particularly constructed and arranged to cause the rotor pockets to initially open to the pumping chamber outlet along only minor parts of their lengths.
  • Another object is to provide a new and improved pump of the type set forth which is particularly constructed and arranged to provide gradual or progressive opening of said pockets to the pumping chamber outlet.
  • Another object is to provide a new and improved pump of the type set forth which is particularly constructed and arranged to delay opening of the rotor pockets to the pumping chamber outlet until displacement of material from the pockets is commenced.
  • a pump may comprise a housing containing a pumping chamber having an inlet and an outlet, rotor means in thepumping chamber provided with a plurality of peripheral rotor pockets and rotatable in a predetermined rotary direction to cause the rotor pockets to be opened to the inlet and the outlet, alternately, and baffle means causing the outlet to,in said predeten'nined rotary direction, include a leading end portion centrally of the rotor pockets dimensioned to open to only a part of the length of each rotor pocket followed by a trailing portion dimenv sioned to open to a longer length of each rotor pocket.
  • FIG. 1 is an elevational sectional view of one form of pump embodying the invention
  • FIG. 2 is an enlarged, elevational sectional view taken on Line 2-2 of FIG. 1, looking in the direction of the arrows, showing the baffle means and pumping chamber outlet of the pump illustrated in FIG. ll;
  • FIG. 3 is a view generally similar to that of FIG. 2, but illustrating a modified form of the baffle means and outlet;
  • FIG. 4 is an elevational sectional view of another form of pump embodying the invention, taken through the center of the baffle means of the pump;
  • FIG. 5 is a fragmentary, elevational sectional view generally similar to FIG. 4, but taken through a side portion of the baffle means;
  • FIG. 6 is an elevational sectional view taken on Line 66 of FIG. 4, looking in the direction of the arrows, showing the baffle means and pumping chamber outlet of the pump of FIGS. 4 and 5; and
  • FIGS. 7 and 8 are views generally similar to FIG. 6, but illustrating modified forms of the baffle means and outlet.
  • FIGS. 1 and 2 illustrate an embodiment of the invention in the form of a pump 10 which, generally considered, is of the character described in my co-pending US. Pat. Application Ser. No. 68,866, filed Sept. 2, 1970, now US. Pat. No. 3,708,249 granted Jan. 2, 1973, and assigned to the assignee of the present invention.
  • the pump 10 comprises a pump housing or casing 12 containing a pump ing chamber 14 having therein a rotor 16 which, throughout the pump operation, is continuously rotatably driven about its longitudinal axis in the rotary direction schematically depicted by the arrow shown thereon in FIG. I.
  • the rotor 16 includes a plurality of identical, peripheral rotor pockets or grooves 18 which extend generally spirally around the rotor longitudinal axis and along their sides are bounded by the side walls 20 of generally spiral land portions 22 of the rotor 16.
  • the rotor pockets l8 longitudinally extend uninterrupted throughout the major portion of the length of the rotor 16 but, as shown in FIG. 2, are at their ends spaced inwardly from the ends of the rotor 16 by annular land portions 24 of the latter.
  • the casing 12 contains a supply-chamber 26 communicating with one side (the left-hand side, as viewed in FIG. 1) of the pumping chamber 14 through the pumping chamber inlet which is designated generally as 28.
  • the inlet 28 extends the full length of the rotor pockets 18 to insure satisfactory feed of material from the supply chamber 26; and throughout the operation of pump 10 the material to be pumped is normally continuously supplied to the supply chamber through the material inlet 30.
  • the supply chamber 26 contains a feed screw 32, constructed such that its rotation causes the material in the supply chamber 26 to be fed through the pumping chamber inlet 28, which during the operation of the pump 10 is rotatably driven to so supply the material.
  • the side of the pumping chamber I4 opposite from the inlet 28 is provided with the pumping cham ber outlet 34 which connects the pumping chamber 14 with a discharge conduit 36, in turn, communicating with conventional piping (not shown) arranged to direct the pumped material to the desired location.
  • the pump also comprises a disc 38 mounted for rotation about an axis which is transverse to the longitudinal axis of the rotor 16 and above the latter axis.
  • the disc 38 includes a plurality of disc lobes 40 which project outwardly from its periphery at spaced locations therearound and are sealingly received in the rotor pockets 18 adjacent to the upper side of the rotor 16 with the generally spiral rotor lands 22 sealingly received in the spaces between the disc lobes 40.
  • the disc 38 is fixedly mounted on a co-axial shaft 42, also carrying the feed screw 32, which is rotatably driven in timed relationship with the rotor 16 by gear means including the gear 44.
  • each rotor pocket 18 received material from the supply chamber 26 through the pumping chamber inlet 28 and contains such received material until the disc lobes 40 discharge it through the pumping chamber outlet 34 to the discharge conduit 36.
  • a baffle means is provided intermediate the pumping chamber 14 and the discharge conduit 36 to cause the rotor pockets 18 to, during the rotation of the rotor 16, each initially open for only a minor part of their length to the discharge conduit 36 and thereafter open for a longer length to the latter.
  • This baffle means moreover, as illustrated, is particularly constructed and arranged to cause each rotor pocket 18 to initially open to the discharge conduit 36 simultaneously with the commencement of the discharge of material from the rotor pocket 18 by the disc lobes 40 and also to cause the open length of the rotor pocket 18 to be gradually or progressively increased.
  • this baffle means comprises an arcuate baffle 48 which also serves as a portion of the wall 46 of the pumping chamber 14 and has an edge 50, non-parallel to the walls bounding the sides of the rotor pockets 18, defining the side of the outlet 34 leading in the rotary direction of the rotor driven rotation.
  • the edge 50 of the baffle 48 cooperates with the side wall 52 of the outlet 34 to cause the end portion 54 of the latter leading in the rotary direction of the rotor rotation to be of length (that is, dimension longitudinally of the rotor pockets 18) only a minor part of the length of each rotor pocket 18.
  • the edge 50 is, moreover, particularly constructed to locate this leading portion 54 of the outlet 34 at a position whereby each rotor pocket opens thereto simultaneously with the initiation of the discharge of material from the rotor pocket 18 by a disc lobe 40.
  • the edge 50 of the baffle 48 throughout its length gradually or progressively slopes away from the outlet side wall 52 in the rotary direction of the rotor rotation to cause the portions 56 of the outlet 34 trailing in such rotary direction to be of progressively increasing length (that is, dimension longitudinally of the rotor pockets l8) and hence longer than the outlet leading portion 54.
  • the employed baffle means does not need to be of the configuration of the aforedescribed baffle 48, but rather may alternatively be of other construction and arrangement suitable to cause the outlet 34 to, in the rotary direction of the rotor rotation, include a leading portion dimensioned to open to only a part of the length of each rotor pocket 18 followed by a trailing portion dimensioned to open to a longer length of each rotor pocket 18.
  • FIG. 3 wherein parts similar to those shown in FIGS.
  • baffle 4811 which is particularly constructed to cause the outlet 34a to extend the full length of the portion of the rotor 16a between the annular lands 24a and has an edge 50a including portions 58,60 of differing slope.
  • suitable baffle means may be readily constructed for the pump 10.
  • the driven rotation of the rotor 16 causes the rotor pockets 18 containing material received through the pumping chamber inlet 28 to be initially opened to the discharge conduit 36 through the outlet 34 for only minor parts of their lengths. Also, material is discharged from the rotor pockets l8 simultaneously with their opening to the outlet leading portion 54. Hence, in this manner the aforementioned vibration and hammering-type noise is substantially minimized; and material commences to be discharged from the rotor pickets l8 simultaneously with their opening to the outlet leading portion 54.
  • FIGS. 4 through 6 illustrate an embodiment of the invention in the form of a pump 62 which, generally considered, is of the character described in US. Pat. No. 3,001,481, issued Sept. 26, I96] and assigned to the assignee of the present invention.
  • the pump 62 comprises a pump housing or casing 64 containing a pumping chamber 66 which, in turn, contains a pair of elon gated rotors 68, 70.
  • One side of the pumping chamber 66 is provided with an inlet 72 communicating through an inlet conduit 74 with a source of the material to be pumped; the opposite side of the pumping chamber 66 is provided with an outlet, designated generally as 76, which is connected to a discharge conduit 78 arranged to convey the pumped materials to the desired location.
  • the rotors 68,70 are throughout the pump operation rotatably driven about their longitudinal axes in the opposite rotary directions schematically depicted by the arrows shown thereon in FIG. 4.
  • the rotors 68,70 are of identical construction and each include a plurality of peripheral rotor pockets 80 along opposite sides bounded by the side walls 82 of the lobes 84 of the rotors 78,70.
  • the pockets 80 longitudinally extend parallel to the axes of the rotors 68,70; and in the conventional manner the lobes 84 of each rotor 68,70 are received in the pockets 80 of the other thereof during an arcuate portion of the rotation of the rotors 68,70.
  • the baffle means employed in this embodiment of the invention is particularly constructed to cause the rotor pockets 80 of both rotors 68,70 to, during rotation of the latter, each initially open for only a minor part of their length to the discharge conduit 78 and thereafter open for a longer length to the latter.
  • this baffle means comprises identical arcuate baffles 86 for each rotor 68,70 both of which baffles 86 serve as portions of the wall 88 of the pumping chamber 66.
  • the baffles 86 each have an edge 90, nonparallel to the walls 82 bounding the sides of the rotor pockets 80, defining the side of the outlet 76 leading in the rotary direction of the driven rotation of the corresponding rotor 68,70.
  • each baffle 86 causes the outlet 76 to include a centrally located end portion 92 (that is, as shown in FIG. 6, an end portion 92 located centrally of the corresponding rotor and its rotor pockets), leading in the rotary direction of the driven rotation of the corresponding rotor, which is of length (that is, dimension longitudinally of the rotor pockets 80 of the rotor 68,70) only a minor part of the length of the rotor pockets 80.
  • each baffle 86 is, moreover, particularly constructed to cause the portions 94 of the outlet 76 trailing such leading portion 92 to be of gradually or progressively increasing length; and intermediate the baffles 86, the outlet 76 includes a portion 96 extending the full length of the rotor pockets 80.
  • the operation of the pump 62 is believed to be apparent in view of the aforegiven description of the operation of the pump 10. More particularly, during the operation of the pump 62 the rotors 68,70 are continuously rotatably driven in the respective rotary directions schematically shown by the arrows in FIG. 4 to alternately connect their rotor pockets 80 with the pumping chamber inlet 72 and outlet 76.
  • the pockets 80 of both rotors 68,70 each initially communicate with the corresponding leading portions 92 of the out let 76, thereby providing the aforedescribed benefits attained by the invention, and subsequently communicate with the outlet trailing and full length portions 94,96 through which material is discharged from the rotor pockets 80.
  • FIG. 7,.wherein parts corresponding to those shown in FllGS. 4 through 6 are designated by the reference character for the aforedescribed similar part followed by the suffix a illustrates one suitable alternative form of baffle means
  • FIG. 8 wherein parts corresponding to those shown in FIGS. 4 through 6 are designated by the reference character for the aforedescribed similar part followed by the suffix b, illustrates another suitable alternative form of baffle means.
  • FIG. 8 wherein parts corresponding to those shown in FIGS. 4 through 6 are designated by the reference character for the aforedescribed similar part
  • baffle means is different from all of the other illustrated baffle means in that the baffles 86b do not cause the outlet to be of gradually or progressively increasing length, and the edges 90b of the baffles 86b include portions parallel to the sides of the rotor pockets. Also, as will be seen from FIGS. 6 and 8, the baffles 86, 86b cause the therein shown outlets to be of cruciform or cross-like configuration.
  • a pump comprising a housing containing a pumping chamber having an inlet and an outlet; a rotor in said pumping chamber provided with a plurality of peripheral rotor pockets and rotatable in a predetermined rotary direction to open said rotorpockets to said inlet and said outlet, alternately; and baffle means operatively associated with said outlet for causing said outlet to, in said predetermined rotary direction, include a leading end portion centrally of said rotor pockets and of dimension longitudinally of said rotor pockets only a minor part of the length of each said rotor pocket followed by a trailing portion of greater dimension longitudinally of said rotor pockets than said leading end portion whereby, during rotation of said rotor means in said predetermined rotary direction, each said rotor pocket opens first to said centrally located leading end portion of said outlet and thereafter to said trailing portion thereof.
  • a pump according to claim ll wherein said outlet progressively increases in dimension longitudinally of said rotor in said predetermined rotor direction.
  • a pump according to claim I wherein said outlet includes a portion which extends the full length of said rotor pockets.
  • a pump according to claim I wherein said outlet progressively increases in dimension longitudinally of said rotor in said predetermined rotary direction, and said outlet includes a portion which extends the full length of said rotor pockets.
  • a pump according to claim I further comprising a second rotor in said pumping chamber; said second rotor being provided with a pluralltiy of peripheral sec ond rotor pockets and being rotatable in a second pre determined rotary direction opposite to said first pre determined rotary direction to open said second rotor pockets to said inlet and said outlet, alternately; and said baffle means causing said outlet to, in said second predetermined rotary direction, include a leading end portion centrally of said rotor pockets and of dimension longitudinally of said rotor pockets only a minor portion of the length of each said second rotor pocket followed by a trailing portion of greater dimension lon gitudinally of said rotor pockets than said leading end portion whereby, during rotation of said second rotor means in said second predetermined rotary direction, each of said second rotor pockets opens first to each centrally located leading end portion of said outlet and thereafter to such trailing portion thereof.
  • a pump according to claim S wherein said outlet is of cruciform configuration.
  • a pump according to claim 5 wherein said outlet progressively increases in dimension longitudinally of said rotor in each said rotary direction, and said outlet intermediate said leading end portions includes a full length portion extending the full length of said rotor pockets.
  • a pump comprising a housing containing a pump ing chamber having an inlet and an outlet; rotor means in said pumping chamber provided with a plurality of peripheral rotor pockets and rotatable in a predetermined rotary direction to cause said rotor pockets to be opened to said inlet and said outlet, alternately; and baffle means causing said outlet to, in said predetermined rotary direction, include a leading end portion centrally of said rotor pockets dimensioned to open to only a minor part of the length of each said rotor pocket followed by a trailing portion dimensioned to open to a longer length of each said rotor pocket.
  • a pump according to claim 10 further comprising second rotor means in said pumping chamber provided with a plurality of peripheral second rotor pockets and rotatable in a predetermined rotary direction to cause said second rotor pockets to be opened to said inlet and said outlet, alternately; said baffle means causing said outlet to, in said predetennined rotary direction of said second rotor means, include a leading end portion centrally of said rotor pockets dimensioned to open to only a part of the length of each said second rotor pocket followed by a trailing portion dimensioned to open to a longer length of each said second rotor 16.
  • said out let intermediate said leading end portions includes a portion extending the full length of said rotor pockets

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Rotary Pumps (AREA)
  • Details And Applications Of Rotary Liquid Pumps (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
  • Eye Examination Apparatus (AREA)
US00186864A 1971-10-06 1971-10-06 Pump having discharge baffle means Expired - Lifetime US3746482A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US18686471A 1971-10-06 1971-10-06

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US3746482A true US3746482A (en) 1973-07-17

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US00186864A Expired - Lifetime US3746482A (en) 1971-10-06 1971-10-06 Pump having discharge baffle means

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US (1) US3746482A (it)
JP (1) JPS4845908A (it)
BR (1) BR7206854D0 (it)
CA (1) CA964933A (it)
DE (1) DE2248490C2 (it)
FI (1) FI54534C (it)
FR (1) FR2155573A5 (it)
GB (1) GB1395385A (it)
IT (1) IT968641B (it)
NO (1) NO137213C (it)
SE (1) SE385315B (it)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5702240A (en) * 1995-05-05 1997-12-30 Tuthill Corporation Rotary positive displacement blower having a diverging outlet part
US20100086402A1 (en) * 2008-10-07 2010-04-08 Eaton Corporation High efficiency supercharger outlet
CN104763639A (zh) * 2014-01-04 2015-07-08 临安创投机械有限公司 一种用于粘稠液抽取的液泵

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1021180A (en) * 1911-01-19 1912-03-26 Archer E Clifton Construction of rotary blowers and pumps.
US1670681A (en) * 1925-03-30 1928-05-22 Haas Rudolf Rotary pump, motor, and meter
DE600971C (de) * 1932-01-20 1934-08-04 Maschf Augsburg Nuernberg Ag Kapselgeblaese mit Geblaesefluegeln, die an ihrem aeusseren Umfang vollkommen abgerundet sind
US2480818A (en) * 1943-05-11 1949-08-30 Joseph E Whitfield Helical rotary fluid handling device
US2531726A (en) * 1946-01-26 1950-11-28 Roper Corp Geo D Positive displacement rotary pump
DE925906C (de) * 1952-04-03 1955-03-31 Daimler Benz Ag Drehkolbengeblaese, insbesondere Rootsgeblaese fuer Brennkraftmaschinen

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT37680B (de) * 1906-11-27 1909-06-25 Bruno Beier Kraftmaschine mit kreisendem Kolben, deren Arbeitsraum durch eine schraubengangförmige Nut der Kolbentrommel gebildet wird.
US2871794A (en) * 1953-06-01 1959-02-03 Roper Ind Inc Gear pump or fluid motor
DE1264958B (de) * 1960-10-08 1968-03-28 Bosch Gmbh Robert Zahnradpumpe oder -motor

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1021180A (en) * 1911-01-19 1912-03-26 Archer E Clifton Construction of rotary blowers and pumps.
US1670681A (en) * 1925-03-30 1928-05-22 Haas Rudolf Rotary pump, motor, and meter
DE600971C (de) * 1932-01-20 1934-08-04 Maschf Augsburg Nuernberg Ag Kapselgeblaese mit Geblaesefluegeln, die an ihrem aeusseren Umfang vollkommen abgerundet sind
US2480818A (en) * 1943-05-11 1949-08-30 Joseph E Whitfield Helical rotary fluid handling device
US2531726A (en) * 1946-01-26 1950-11-28 Roper Corp Geo D Positive displacement rotary pump
DE925906C (de) * 1952-04-03 1955-03-31 Daimler Benz Ag Drehkolbengeblaese, insbesondere Rootsgeblaese fuer Brennkraftmaschinen

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5702240A (en) * 1995-05-05 1997-12-30 Tuthill Corporation Rotary positive displacement blower having a diverging outlet part
US20100086402A1 (en) * 2008-10-07 2010-04-08 Eaton Corporation High efficiency supercharger outlet
US8096288B2 (en) 2008-10-07 2012-01-17 Eaton Corporation High efficiency supercharger outlet
CN104763639A (zh) * 2014-01-04 2015-07-08 临安创投机械有限公司 一种用于粘稠液抽取的液泵

Also Published As

Publication number Publication date
NO137213B (no) 1977-10-10
FI54534B (fi) 1978-08-31
FI54534C (fi) 1978-12-11
FR2155573A5 (it) 1973-05-18
SE385315B (sv) 1976-06-21
CA964933A (en) 1975-03-25
GB1395385A (en) 1975-05-29
JPS4845908A (it) 1973-06-30
IT968641B (it) 1974-03-20
DE2248490A1 (de) 1973-04-12
DE2248490C2 (de) 1984-03-22
BR7206854D0 (pt) 1973-08-21
NO137213C (no) 1978-01-18

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