US20200271127A1 - Centrifugal Pump - Google Patents
Centrifugal Pump Download PDFInfo
- Publication number
- US20200271127A1 US20200271127A1 US16/790,893 US202016790893A US2020271127A1 US 20200271127 A1 US20200271127 A1 US 20200271127A1 US 202016790893 A US202016790893 A US 202016790893A US 2020271127 A1 US2020271127 A1 US 2020271127A1
- Authority
- US
- United States
- Prior art keywords
- main plate
- radially
- impeller
- outer blade
- radially outer
- 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
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/40—Casings; Connections of working fluid
- F04D29/42—Casings; Connections of working fluid for radial or helico-centrifugal pumps
- F04D29/4206—Casings; Connections of working fluid for radial or helico-centrifugal pumps especially adapted for elastic fluid pumps
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/18—Rotors
- F04D29/22—Rotors specially for centrifugal pumps
- F04D29/24—Vanes
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/18—Rotors
- F04D29/22—Rotors specially for centrifugal pumps
- F04D29/24—Vanes
- F04D29/242—Geometry, shape
- F04D29/245—Geometry, shape for special effects
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/26—Rotors specially for elastic fluids
- F04D29/28—Rotors specially for elastic fluids for centrifugal or helico-centrifugal pumps for radial-flow or helico-centrifugal pumps
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/66—Combating cavitation, whirls, noise, vibration or the like; Balancing
- F04D29/669—Combating cavitation, whirls, noise, vibration or the like; Balancing especially adapted for liquid pumps
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D7/00—Pumps adapted for handling specific fluids, e.g. by selection of specific materials for pumps or pump parts
- F04D7/02—Pumps adapted for handling specific fluids, e.g. by selection of specific materials for pumps or pump parts of centrifugal type
Definitions
- This disclosure relates generally to centrifugal pumps.
- One type of conventional centrifugal pump includes an impeller rotated by a motor, and a housing defining a pump chamber therein.
- the impeller is housed in the pump chamber and has a main plate with a circular shape and a plurality of blades radially extending on a top surface of the main plate.
- the housing includes an inlet port and an outlet port in fluid communication with the pump chamber.
- the inlet port is formed such that fluid flows into the pump chamber toward a central portion of the top surface of the impeller in a direction perpendicular to the top surface of the main plate of the impeller.
- the outlet port is formed such that the fluid is discharged from the pump chamber by rotation of the impeller in a tangential direction.
- the housing of the centrifugal pump includes a partition wall that divides the pump chamber from a flow passage in the outlet port.
- a centrifugal pump in one aspect of this disclosure, includes an impeller rotated by a motor in a rotational direction about a central axis and a housing defining a pump chamber therein.
- the impeller is housed in the pump chamber and includes a main plate having a circular shape and a first surface extending perpendicular to the central axis.
- the impeller also includes a plurality of blades projecting axially from the first surface of the main plate and extending radially along the first surface.
- the housing has an inlet port configured to supply fluid into the pump chamber axially toward a center of the first surface of the main plate.
- the housing also has an outlet port configured to discharge the fluid by rotation of the impeller in a tangential direction relative to the central axis.
- Each of the blades includes a radially inner blade part and a radially outer blade part that extends radially outward from the radially inner blade part.
- the radially outer blade part of each blade has a leading surface relative to the rotational direction that extends from the main plate obliquely either frontward or rearward relative to the rotational direction.
- each radially outer blade part extends from the main plate obliquely either frontward or rearward in the rotational direction. Due to this configuration, as each of the radially outer blade parts comes close to the outlet port, the radially outer blade part gradually decreases an opening area defined by the outlet port. Thus, a drastic increase in pressure can be suppressed, thereby offering the potential to decrease vibration and noise caused by pressure pulsations in the centrifugal pump.
- FIG. 1 is a partial cross-sectional view of a first embodiment of an embodiment of a centrifugal pump in accordance with the principles described herein.
- FIG. 2 is a cross-sectional view of the centrifugal pump of FIG. 1 taken along line II-II in FIG. 1 .
- FIG. 3 is a perspective view of the impeller of FIG. 1 .
- FIG. 4 is a plan view of the impeller of FIG. 1 .
- FIG. 5 is a cross-sectional view of the impeller of FIG. 4 taken along line V-V in FIG. 4 .
- FIG. 6 is a cross-sectional view of the impeller of FIG. 4 taken along line VI-VI in FIG. 4 .
- FIG. 7 is a cross-sectional view of the impeller of FIG. 4 taken along line VII-VII in FIG. 4 .
- FIG. 8 is a partial cross-sectional view of a second embodiment of a centrifugal pump in accordance with the principles described herein.
- FIG. 9 is a cross-sectional view of the centrifugal pump of FIG. 8 taken along line IX-IX in FIG. 8 .
- FIG. 10 is a perspective view of the impeller in FIG. 8 .
- FIG. 11 is a plan view of the impeller of FIG. 8 .
- FIG. 12 is a cross-sectional view of the impeller of FIG. 11 taken along line MI-MI in FIG. 11 .
- FIG. 13 is a cross-sectional view of the impeller of FIG. 11 taken along line in FIG. 11 .
- FIG. 14 is a cross-sectional view of the impeller of FIG. 11 taken along line XIV-XIV in FIG. 11 .
- FIG. 15 is a cross-sectional view of a radially outer blade part of an embodiment of an impeller in accordance with principles described herein.
- FIG. 16 is a cross-sectional view of a radially outer blade part of an embodiment of an impeller in accordance with principles described herein.
- centrifugal pump includes blades extending linearly in both a radial direction and an axial direction relative to the central axis of rotation of the impeller.
- the centrifugal pump includes blades extending linearly in both a radial direction and an axial direction relative to the central axis of rotation of the impeller.
- a centrifugal pump 10 is used as a purge pump mounted on a vehicle, such as an automobile.
- the purge pump is configured to compensate for a shortage of purge gas flowing from a canister to an air intake passage of an internal combustion engine.
- Exemplary coordinate axes are shown in FIGS. 1 and 2 for purposes of further explanation and clarity. However, these coordinate axes do not limit the orientation or the mounting direction of the centrifugal pump 10 on the vehicle.
- the centrifugal pump 10 of the first embodiment includes a housing 11 having a substantially a hollow cylindrical shape.
- the centrifugal pump 10 also includes a pump section 12 at an upper portion of the housing 11 and a motor section 14 positioned below the pump section 12 .
- the motor section 14 includes a brushless motor and a rotational shaft 15 extending in the vertical direction.
- the rotational shaft 15 has a central axis (also extending in the vertical direction) that defines a rotational axis of an impeller 30 of centrifugal pump 10 .
- the motor section 14 may also be referred to herein as a “motor.”
- the housing 11 defines a pump chamber 17 in an upper portion thereof.
- the pump chamber 17 may have a hollow short cylindrical shape and be coaxially aligned with the rotational shaft 15 of the motor section 14 .
- the housing 11 is divided in the axial direction into an upper housing member 11 a and a lower housing member 11 b .
- the pump chamber 17 is formed by the upper housing member 11 a and the lower housing member 11 b being coupled together.
- the pump chamber 17 has a volute part 17 a formed at an outer circumference thereof.
- the rotational shaft 15 of the motor section 14 penetrates the lower housing member 11 b and protrudes axially into the pump chamber 17 .
- the upper housing member 11 a includes an inlet port 20 that may have a hollow cylindrical shape extending upward from a top surface of the upper housing member 11 a .
- the inlet port 20 is coaxially aligned with the pump chamber 17 and the rotational shaft 15 .
- the inlet port 20 defines an inflow passage 20 a therein.
- the inflow passage 20 a provides fluid communication between the inside and the outside of the pump chamber 17 .
- the upper housing member 11 a of the housing 11 includes an outlet port 22 that may have a hollow cylindrical shape extending leftward in FIGS. 1 and 2 from a front portion of the upper housing member 11 a .
- the outlet port 22 extends tangentially from the radially outer perimeter of the pump chamber 17 .
- the outlet port 22 defines an outflow passage 22 a therein.
- the outflow passage 22 a provides fluid communication between the inside and the outside of the pump chamber 17 .
- the upper housing member 11 a of the housing 11 includes a partition wall 24 separating and dividing the outflow passage 22 a from the volute part 17 a of the pump chamber 17 .
- the outlet port 22 includes an upstream open end 22 b positioned at or proximal the volute part 17 a of the pump chamber 17 .
- the upstream open end 22 b has an elliptical shape with a major axis extending in the horizontal direction.
- the upstream open end 22 b may have another shape, such as a rectangular shape.
- the impeller 30 is rotatably disposed in the pump chamber 17 .
- the impeller 30 is coaxially aligned with the rotational shaft 15 and is fixably mounted to an upper end of the rotational shaft 15 of the motor section 14 .
- rotational direction R is in a clockwise direction.
- the impeller 30 may be made from a resin material.
- the inlet port 20 generally faces a central portion of a blade side of the impeller 30 (i.e. a central portion of the top surface side of the impeller 30 in this embodiment).
- the impeller 30 When the motor section 14 is driven using electricity supplied from an external power source, the impeller 30 is rotated together with the rotational shaft 15 , so that fluid, in this embodiment purge gas, is suctioned into the pump chamber 17 via the inflow passage 20 a of the inlet port 20 .
- the purge gas is pressurized and then discharged into the outflow passage 22 a via the upstream open end 22 b of the outlet port 22 due to the rotation of the impeller 30 .
- the centrifugal pump 10 pumps the purge gas.
- a radially outer end of at least one of the blades 36 of the impeller 30 passes close to the partition wall 24 .
- the impeller 30 includes a main plate 32 , a boss 34 , and a plurality of blades 36 mounted to main plate 32 .
- the main plate 32 has substantially a circular plate shape extending perpendicular to the rotational shaft 15 and the central axis thereof.
- the main plate 32 includes a convex part 32 a on an upper surface thereof.
- the convex part 32 a has a truncated cone shape surrounding the boss 34 .
- the upper surface of the main plate 32 may also be referred to herein as “a first surface” of the main plate 32 .
- the boss 34 is formed in a hollow cylindrical shape having a closed top and an open bottom.
- the boss 34 is coaxially disposed at a central portion of the upper surface of the main plate 32 .
- the rotational shaft 15 of the motor section 14 is fixedly inserted into the boss 34 .
- each of the blades 36 protrudes axially upward from the upper surface of the main plate 32 and extends radially along the upper surface of the main plate 32 .
- Each of the blades generally has an elongated, generally rectangular plate shape oriented in the radial direction.
- all of the blades 36 may have the same shape as each other. Accordingly, only one of the blades 36 will be described for convenience of explanation with the understanding the other blades 36 are the same.
- a radially inner end of the blade 36 is coupled to the boss 34 and deviates forward from a virtual line, which extends between a radially outer end of the blade 36 and a rotational center 30 c of the impeller 30 defined by the rotational axis of shaft 15 .
- an upper edge of the blade 36 gently curves rearward relative to the rotational direction of the impeller 30 from the radially inner end toward the radially outer end of the blade 36 .
- a lower edge of the blade 36 may also be referred to herein as “a main plate side part” of the blade 26 , and the upper edge of the blade 36 may also be referred to herein as “an opposite side part” of the blade 26 .
- the plan view illustrated by FIG. 4 corresponds to “a plan view of the impeller” in this disclosure.
- the blade 36 is divided into a radially inner blade part 37 and a radially outer blade part 38 .
- the radially inner blade part 37 extends radially from the boss 34 to the corresponding radially outer blade part 38
- the radially outer blade part 38 extends radially outward from the radially inner blade part 37 .
- a radial vector N of the main plate 32 passes through both the rotation center 30 c of the impeller 30 and a connection part between the inner blade part 37 and the outer blade part 38 .
- the inner blade part 37 is positioned in front of the radial vector N relative to the rotational direction R of the impeller 30 .
- a radially outer end of the inner blade part 37 is contiguous with and coupled to a radially inner end of the outer blade part 38 .
- the blade 36 includes a front surface facing forward relative to the direction of rotation R and a rear surface facing rearward relative to the direction of rotational R.
- the radial vector N may pass through the front surface of the blade 36 at the radially inner end of the outer blade part 38 .
- the inner blade part 37 of the blade 36 includes a front surface 37 a and a rear surface 37 b , each of which extends perpendicular to the upper surface of the main plate 32 (i.e., axially relative to the rotational axis).
- perpendicular includes both perpendicular and substantially perpendicular.
- a front surface 38 a of the outer blade part 38 of the blade 36 extends from the upper surface of the main plate 32 obliquely rearward relative to the rotational direction of the impeller 30 .
- an angle formed between the upper surface of the main plate 32 and a lower end of the front surface 38 a of the outer blade part 38 may be oblique.
- the front surface 37 a of the inner blade part 37 and the front surface 38 a of the outer blade part 38 are contiguous with each other. As shown in FIGS.
- the front surface 38 a extends linearly between its upper end and a lower end in this embodiment.
- the front surface 38 a may be gently curved in a concave or convex manner in some embodiments.
- the front surface 38 a of the outer blade part 38 defines an included angle 380 with a straight line L that extending perpendicular to the upper surface of the main plate 32 and passing through the upper end of the front surface 38 a . That is, the included angle 380 is formed by the front surface 38 a and the straight line L and is acute. The included angle 380 between the front surface 38 a and the straight line L gradually increases from the radially inner end toward the radially outer end of the outer blade part 38 .
- the direction along which the straight line L is disposed may also be referred to herein as an “axis disposed in the first direction.”.
- a lower half of the front surface 38 a of the radially outer end of the outer blade part 38 is positioned in front of the radial vector N relative to the rotational direction R, and an upper half of this portion of the front surface 38 a is positioned rearward of the radial vector N relative to the rotational direction R.
- a dashed line N′ shows a straight line extending vertically and perpendicular to the radial vector N.
- a radially outer end surface of the outer blade part 38 is flush with an outer periphery of the main plate 32 .
- a lower half of the front surface 38 a may also be referred to herein as “a main plate side part.”, and the upper half of the front surface 38 a may also be referred to herein as “an opposite side part”.
- the direction along which the radial vector N is disposed may also be referred to herein as a “normal axis.”
- a thickness 38 t of the outer blade part 38 in the rotational direction R gradually increases from the upper end toward the lower end of the outer blade part 38 .
- the rear surface 38 b of the outer blade part 38 extends perpendicular to the upper surface of the main plate 32 .
- the rear surface 38 b of the outer blade part 38 is contiguous with the rear surface 37 b of the inner blade part 37 .
- a thickness 37 t of the inner blade part 37 in the rotational direction R is constant between an upper end and a lower end of the inner blade part 37 .
- the term “constant” includes both constant and substantially constant.
- the front surface 38 a of the outer blade part 38 of each blade 36 extends from the upper surface of the main plate 32 obliquely rearward relative to the rotational direction R
- the radially outer end of each outer blade part 38 comes close to the partition wall 24 , the radially outer end gradually decreases the opening area of the upstream open end 22 b of the outlet port 22 . Accordingly, a drastic increase in pressure can be suppressed, so that vibration and noise caused by pressure pulsations in the centrifugal pump 10 can be decreased.
- the included angle 380 between the front surface 38 a and the straight line L gradually increases from the radially inner end toward the radially outer end of the outer blade part 38 .
- Such configuration of the front surface 38 a can smoothen the fluid flow outward in the radial direction of the impeller 30 .
- the lower half of the front surface 38 a of the radially outer end of each outer blade part 38 is positioned in front of the radial vector N in the rotational direction R.
- the pressurizing performance of the centrifugal pump 10 is increased, so that the number of revolution required for achieving a predetermined pressure can be decreased.
- the upper half of the front surface 38 a of the radially outer end of each outer blade part 38 is positioned rearward of the radial vector N relative to the rotational direction R.
- Such configuration can smoothen the fluid flow outward in the radial direction of the impeller 30 so as to decrease a load torque on the impeller 30 . Accordingly, a decrease in both the number of revolution of the centrifugal pump 10 and the load torque on the impeller 30 is achieved, thereby improving pump efficiency.
- each outer blade part 38 gradually increases from the upper end toward the lower end of the outer blade part 38 .
- the rigidity of the outer blade part 38 can be improved, thereby further reducing vibration and noise.
- each outer blade part 38 extends upward from the main plate 32 in a direction perpendicular to the upper surface of the main plate 32 . So, when the impeller 30 is made from a resin material using molds, at least one of the molds, which shapes the corresponding rear surface 38 b , can be removed in the axial direction of the impeller 30 . Accordingly, the molds can be simplified, thereby improving manufacturing of the impeller 30 .
- a second embodiment will be described with reference to FIGS. 8 to 14 .
- the second embodiment is substantially the same as the first embodiment described above with some differences regarding the outer blade parts 38 of the impeller 30 .
- the differences will be described, similar configurations will not be described in the interest of conciseness.
- each of the blades 36 includes a radially outer blade part 138 extending radially outward from the radial outer end of the inner blade part 37 .
- all of the outer blade parts 138 have substantially the same shape as each other. Accordingly, only one radially outer blade part 138 will be described with the understanding the other radially outer blade parts 138 are the same.
- the outer blade part 138 includes a front surface 138 a extending from the main plate 32 of the impeller 30 obliquely frontward relative to the rotational direction R of the impeller 30 .
- the inner blade part 37 of the second embodiment has the same shape as that of the first embodiment.
- an included angle 1380 of the front surface 138 a which is defined by the front surface 138 a and a straight line L that extends perpendicular to the upper surface of the main plate 32 and passes through the upper end of the front surface 138 a , is acute.
- the included angle 1380 formed between the front surface 138 a and the straight line L gradually increases from the radially inner end toward the radially outer end of the outer blade part 138 .
- FIG. 11 one radial vector N of the boss 34 is shown.
- the radial vector N passes through both the rotation center 30 c of the impeller 30 and a connection part between the inner blade part 37 and the outer blade part 138 .
- an upper half of the front surface 138 a of the radially outer end of the outer blade part 138 is positioned in front of the radial vector N relative to the rotational direction R of the impeller 30
- a lower half of the front surface 138 a of the radially outer end of the outer blade part 138 is positioned rearward of the radial vector N relative to the rotational direction R.
- the thickness 138 t of the outer blade part 138 is constant between an upper end and a lower end of the outer blade part 138 .
- the thickness 138 t is constant between the radially inner end and the radially outer end of the outer blade part 138 , i.e. over the longitudinal whole length of the outer blade part 138 .
- an outer periphery of the main plate 32 is concave and curved radially inward between each pair of adjacent blades 36 , such that the radial length of the main plate 32 gradually decreases from a front of each blade 36 toward the adjacent blade 36 in a direction opposite to the rotational direction R. Due to this configuration, the main plate 32 defines a plurality of circumferentially-spaced openings 140 along the outer periphery thereof such that each of the front surfaces 138 a of the outer blade part 138 faces a corresponding opening 140 .
- the front surface 138 a of the outer blade part 138 of each blade 36 of the impeller 30 extends from the upper surface of the main plate 32 obliquely frontward relative to the rotational direction R of the impeller 30 .
- the radially outer end of each outer blade part 138 comes close to the partition wall 24 of the housing 11 , which is illustrated in FIGS. 8 and 9 , the radially outer end gradually decreases the opening area of the upstream open end 22 b of the outlet port 22 . Accordingly, a drastic increase in pressure can be prevented, thereby decreasing vibration and noise caused by pressure pulsations of the centrifugal pump 10 .
- the included angle 1380 formed between the front surface 138 a and the straight line L gradually increases from the radially inner end toward the radially outer end of the outer blade part 138 .
- Such configuration of the outer blade part 138 can smoothen the fluid flow outward in the radial direction of the impeller 30 .
- the upper half of the front surface 138 a of the radially outer end of each outer blade part 138 is positioned in front of the radial vector N in the rotational direction R.
- pressurizing performance of the centrifugal pump 10 is increased, so that the number of revolution required for achieving a predetermined pressure can be decreased.
- the lower half of the front surface 138 a of the radially outer end of each outer blade part 138 is positioned rearward of the radial vector N in the rotational direction R.
- Such configuration can smoothen the fluid flow outward in the radial direction of the impeller 30 so as to decrease a load torque on the impeller 30 . Accordingly, a decrease in both the number of revolution of the centrifugal pump 10 and the load torque on the impeller 30 is achieved, thereby improving pump efficiency.
- the main plate 32 defines the openings 140 that the front surfaces 138 a of the outer blade parts 138 face. So, when the impeller 30 is made from a resin material using molds, at least one of the molds, shaping the corresponding front surface 138 a , can be removed in the axial direction of the impeller 30 . Accordingly, the mold can be simplified, thereby improving manufacturing of the impeller 30 .
- a third embodiment will be described with reference to FIG. 15 .
- the third embodiment is substantially the same as the second embodiment described above with some modifications regarding the outer blade parts 138 of the impeller 30 .
- the differences will be described, similar configurations will not be described in the interest of conciseness.
- a radially outer blade part 238 of each blade 36 includes a front surface 238 a formed with a similar configuration as the front surface 138 a of the second embodiment.
- the outer blade part 238 is also shaped such that its thickness 238 f in the rotational direction R gradually increases from the upper end toward the lower end of the outer blade part 238 .
- the rigidity of the outer blade parts 238 can be increased, thereby reducing vibration and breakage of the outer blade parts 238 .
- a fourth embodiment will be described with reference to FIG. 16 .
- the fourth embodiment is substantially the same as the first embodiment described above with some modifications regarding the outer blade parts 38 of the impeller 30 .
- the differences will be described, similar configurations will not be described in the interest of conciseness.
- each radially outer blade part 338 of the impeller 30 includes a front surface 338 a formed with a similar configuration as the front surface 38 a of the first embodiment.
- the thickness 338 t of the outer blade part 338 is constant between an upper end and a lower end of the outer blade part 338 . That is, a rear surface 338 a of each outer blade part 338 faces obliquely downward relative to the rotational direction R.
- an outer periphery of a main plate 332 is concave and curved radially inward between each pair of circumferentially adjacent blades 36 , such that the radial length of the main plate 332 gradually increases from a front of one blade 36 toward an adjacent blade 36 .
- the main plate 332 of the impeller 30 defines a plurality of circumferentially-spaced openings 340 along the outer periphery thereof, such that each of the rear surfaces 338 b of the outer blade part 338 faces the corresponding opening 340 .
- the impeller 30 when the impeller 30 is made from a resin material using molds, at least one of the molds, shaping the corresponding rear surface 338 b , can be removed in the axial direction of the impeller 30 . Accordingly, the molds can be simplified, thereby improving manufacturing of the impeller 30 .
- the centrifugal pump 10 may be used for pumping various fluid, such as air, other than a purge gas.
- the brushless motor of the motor section 14 may be replaced with a brushed motor.
- the centrifugal pump 10 may be comprised of the motor section 14 only such that the rotational shaft 15 is rotated by a driving source that is provided outside the centrifugal pump 10 .
- the impeller 30 may be made from a metal material.
Abstract
A centrifugal pump includes an impeller rotated about a rotational axis in a rotational direction by a motor and a housing defining a pump chamber therein. The impeller is housed in the pump chamber. The impeller includes a main plate having substantially circular shape and a first surface extending perpendicular to the rotational axis. The main plate is provided with a plurality of blades projecting axially from the first surface and extending radially along the first surface. Each of the blades has a radially inner blade part and a radially outer blade part extending radially outward from the radially inner blade part. Each of the outer blade parts has a front surface that extends from the main plate obliquely either frontward or rearward relative to the rotational direction.
Description
- This application claims priority to Japanese patent application serial number 2019-029401, filed Feb. 21, 2019, which is incorporated herein by reference in its entirety for all purposes.
- Not applicable.
- This disclosure relates generally to centrifugal pumps.
- One type of conventional centrifugal pump includes an impeller rotated by a motor, and a housing defining a pump chamber therein. The impeller is housed in the pump chamber and has a main plate with a circular shape and a plurality of blades radially extending on a top surface of the main plate. The housing includes an inlet port and an outlet port in fluid communication with the pump chamber. The inlet port is formed such that fluid flows into the pump chamber toward a central portion of the top surface of the impeller in a direction perpendicular to the top surface of the main plate of the impeller. The outlet port is formed such that the fluid is discharged from the pump chamber by rotation of the impeller in a tangential direction. The housing of the centrifugal pump includes a partition wall that divides the pump chamber from a flow passage in the outlet port.
- In one aspect of this disclosure, a centrifugal pump includes an impeller rotated by a motor in a rotational direction about a central axis and a housing defining a pump chamber therein. The impeller is housed in the pump chamber and includes a main plate having a circular shape and a first surface extending perpendicular to the central axis. The impeller also includes a plurality of blades projecting axially from the first surface of the main plate and extending radially along the first surface. The housing has an inlet port configured to supply fluid into the pump chamber axially toward a center of the first surface of the main plate. The housing also has an outlet port configured to discharge the fluid by rotation of the impeller in a tangential direction relative to the central axis. Each of the blades includes a radially inner blade part and a radially outer blade part that extends radially outward from the radially inner blade part. The radially outer blade part of each blade has a leading surface relative to the rotational direction that extends from the main plate obliquely either frontward or rearward relative to the rotational direction.
- In accordance with this aspect, the leading surface of each radially outer blade part extends from the main plate obliquely either frontward or rearward in the rotational direction. Due to this configuration, as each of the radially outer blade parts comes close to the outlet port, the radially outer blade part gradually decreases an opening area defined by the outlet port. Thus, a drastic increase in pressure can be suppressed, thereby offering the potential to decrease vibration and noise caused by pressure pulsations in the centrifugal pump.
- For a detailed description of the preferred embodiments of the present teaching, reference will now be made to the accompanying drawings.
-
FIG. 1 is a partial cross-sectional view of a first embodiment of an embodiment of a centrifugal pump in accordance with the principles described herein. -
FIG. 2 is a cross-sectional view of the centrifugal pump ofFIG. 1 taken along line II-II inFIG. 1 . -
FIG. 3 is a perspective view of the impeller ofFIG. 1 . -
FIG. 4 is a plan view of the impeller ofFIG. 1 . -
FIG. 5 is a cross-sectional view of the impeller ofFIG. 4 taken along line V-V inFIG. 4 . -
FIG. 6 is a cross-sectional view of the impeller ofFIG. 4 taken along line VI-VI inFIG. 4 . -
FIG. 7 is a cross-sectional view of the impeller ofFIG. 4 taken along line VII-VII inFIG. 4 . -
FIG. 8 is a partial cross-sectional view of a second embodiment of a centrifugal pump in accordance with the principles described herein. -
FIG. 9 is a cross-sectional view of the centrifugal pump ofFIG. 8 taken along line IX-IX inFIG. 8 . -
FIG. 10 is a perspective view of the impeller inFIG. 8 . -
FIG. 11 is a plan view of the impeller ofFIG. 8 . -
FIG. 12 is a cross-sectional view of the impeller ofFIG. 11 taken along line MI-MI inFIG. 11 . -
FIG. 13 is a cross-sectional view of the impeller ofFIG. 11 taken along line inFIG. 11 . -
FIG. 14 is a cross-sectional view of the impeller ofFIG. 11 taken along line XIV-XIV inFIG. 11 . -
FIG. 15 is a cross-sectional view of a radially outer blade part of an embodiment of an impeller in accordance with principles described herein. -
FIG. 16 is a cross-sectional view of a radially outer blade part of an embodiment of an impeller in accordance with principles described herein. - One conventional centrifugal pump is disclosed in Japanese Laid-Open Patent Publication No. 2008-82268. The centrifugal pump includes blades extending linearly in both a radial direction and an axial direction relative to the central axis of rotation of the impeller. Thus, when each blade comes close to the partition wall dividing the pump chamber from the flow passage in the outlet port, the pressure of fluid therebetween drastically increases. And, just after the blade passes near the partition wall, the pressure of fluid therebetween drastically decreases. Such cyclical pressure changes may generate pressure pulsations, causing vibration and/or noise. Therefore, there has been a need for an improved centrifugal pump.
- The following discussion is directed to various exemplary embodiments. However, one skilled in the art will understand that the examples disclosed herein have broad application, and that the discussion of any embodiment is meant only to be exemplary of that embodiment, and not intended to suggest that the scope of the disclosure, including the claims, is limited to that embodiment.
- A first embodiment will be described with reference to
FIGS. 1 to 7 . In the first embodiment, acentrifugal pump 10 is used as a purge pump mounted on a vehicle, such as an automobile. The purge pump is configured to compensate for a shortage of purge gas flowing from a canister to an air intake passage of an internal combustion engine. Exemplary coordinate axes are shown inFIGS. 1 and 2 for purposes of further explanation and clarity. However, these coordinate axes do not limit the orientation or the mounting direction of thecentrifugal pump 10 on the vehicle. - As shown in
FIG. 1 , thecentrifugal pump 10 of the first embodiment includes ahousing 11 having a substantially a hollow cylindrical shape. Thecentrifugal pump 10 also includes apump section 12 at an upper portion of thehousing 11 and amotor section 14 positioned below thepump section 12. - The
motor section 14 includes a brushless motor and arotational shaft 15 extending in the vertical direction. As will be described in more detail below, therotational shaft 15 has a central axis (also extending in the vertical direction) that defines a rotational axis of animpeller 30 ofcentrifugal pump 10. Themotor section 14 may also be referred to herein as a “motor.” - The
housing 11 defines apump chamber 17 in an upper portion thereof. Thepump chamber 17 may have a hollow short cylindrical shape and be coaxially aligned with therotational shaft 15 of themotor section 14. Thehousing 11 is divided in the axial direction into anupper housing member 11 a and alower housing member 11 b. Thepump chamber 17 is formed by theupper housing member 11 a and thelower housing member 11 b being coupled together. Thepump chamber 17 has avolute part 17 a formed at an outer circumference thereof. Therotational shaft 15 of themotor section 14 penetrates thelower housing member 11 b and protrudes axially into thepump chamber 17. - The
upper housing member 11 a includes aninlet port 20 that may have a hollow cylindrical shape extending upward from a top surface of theupper housing member 11 a. Theinlet port 20 is coaxially aligned with thepump chamber 17 and therotational shaft 15. Theinlet port 20 defines aninflow passage 20 a therein. Theinflow passage 20 a provides fluid communication between the inside and the outside of thepump chamber 17. - As shown in
FIG. 2 , theupper housing member 11 a of thehousing 11 includes anoutlet port 22 that may have a hollow cylindrical shape extending leftward inFIGS. 1 and 2 from a front portion of theupper housing member 11 a. In the plan view, theoutlet port 22 extends tangentially from the radially outer perimeter of thepump chamber 17. Theoutlet port 22 defines anoutflow passage 22 a therein. Theoutflow passage 22 a provides fluid communication between the inside and the outside of thepump chamber 17. Theupper housing member 11 a of thehousing 11 includes apartition wall 24 separating and dividing theoutflow passage 22 a from thevolute part 17 a of thepump chamber 17. - The
outlet port 22 includes an upstreamopen end 22 b positioned at or proximal thevolute part 17 a of thepump chamber 17. As shown inFIG. 1 , in this embodiment, the upstreamopen end 22 b has an elliptical shape with a major axis extending in the horizontal direction. However, in other embodiments, the upstreamopen end 22 b may have another shape, such as a rectangular shape. - The
impeller 30 is rotatably disposed in thepump chamber 17. Theimpeller 30 is coaxially aligned with therotational shaft 15 and is fixably mounted to an upper end of therotational shaft 15 of themotor section 14. Thus, when therotational shaft 15 rotates about its central, rotational axis, theimpeller 30 simultaneously rotates in a rotational direction R about the central, rotational axis of theshaft 15. InFIG. 2 , rotational direction R is in a clockwise direction. Theimpeller 30 may be made from a resin material. As shown inFIG. 1 , theinlet port 20 generally faces a central portion of a blade side of the impeller 30 (i.e. a central portion of the top surface side of theimpeller 30 in this embodiment). - When the
motor section 14 is driven using electricity supplied from an external power source, theimpeller 30 is rotated together with therotational shaft 15, so that fluid, in this embodiment purge gas, is suctioned into thepump chamber 17 via theinflow passage 20 a of theinlet port 20. The purge gas is pressurized and then discharged into theoutflow passage 22 a via the upstreamopen end 22 b of theoutlet port 22 due to the rotation of theimpeller 30. In this manner, thecentrifugal pump 10 pumps the purge gas. When the purge gas is discharged into the upstreamopen end 22 b of theoutlet port 22 via rotation of theimpeller 30, a radially outer end of at least one of theblades 36 of theimpeller 30 passes close to thepartition wall 24. - As shown in
FIG. 3 , theimpeller 30 includes amain plate 32, aboss 34, and a plurality ofblades 36 mounted tomain plate 32. In this embodiment, twelveblades 36 are provided. Themain plate 32 has substantially a circular plate shape extending perpendicular to therotational shaft 15 and the central axis thereof. Themain plate 32 includes aconvex part 32 a on an upper surface thereof. Theconvex part 32 a has a truncated cone shape surrounding theboss 34. The upper surface of themain plate 32 may also be referred to herein as “a first surface” of themain plate 32. Theboss 34 is formed in a hollow cylindrical shape having a closed top and an open bottom. Theboss 34 is coaxially disposed at a central portion of the upper surface of themain plate 32. As shown inFIG. 2 , therotational shaft 15 of themotor section 14 is fixedly inserted into theboss 34. As shown inFIG. 3 , each of theblades 36 protrudes axially upward from the upper surface of themain plate 32 and extends radially along the upper surface of themain plate 32. Each of the blades generally has an elongated, generally rectangular plate shape oriented in the radial direction. - In this embodiment, all of the
blades 36 may have the same shape as each other. Accordingly, only one of theblades 36 will be described for convenience of explanation with the understanding theother blades 36 are the same. As shown inFIG. 4 , a radially inner end of theblade 36 is coupled to theboss 34 and deviates forward from a virtual line, which extends between a radially outer end of theblade 36 and arotational center 30 c of theimpeller 30 defined by the rotational axis ofshaft 15. In the plan view of theimpeller 30, an upper edge of theblade 36 gently curves rearward relative to the rotational direction of theimpeller 30 from the radially inner end toward the radially outer end of theblade 36. A lower edge of theblade 36 may also be referred to herein as “a main plate side part” of the blade 26, and the upper edge of theblade 36 may also be referred to herein as “an opposite side part” of the blade 26. The plan view illustrated byFIG. 4 corresponds to “a plan view of the impeller” in this disclosure. - The
blade 36 is divided into a radiallyinner blade part 37 and a radiallyouter blade part 38. The radiallyinner blade part 37 extends radially from theboss 34 to the corresponding radiallyouter blade part 38, and the radiallyouter blade part 38 extends radially outward from the radiallyinner blade part 37. InFIG. 4 depicting a plan view of theimpeller 30, a radial vector N of themain plate 32 passes through both therotation center 30 c of theimpeller 30 and a connection part between theinner blade part 37 and theouter blade part 38. Theinner blade part 37 is positioned in front of the radial vector N relative to the rotational direction R of theimpeller 30. A radially outer end of theinner blade part 37 is contiguous with and coupled to a radially inner end of theouter blade part 38. Theblade 36 includes a front surface facing forward relative to the direction of rotation R and a rear surface facing rearward relative to the direction of rotational R. The radial vector N may pass through the front surface of theblade 36 at the radially inner end of theouter blade part 38. - As shown in
FIG. 5 , theinner blade part 37 of theblade 36 includes afront surface 37 a and arear surface 37 b, each of which extends perpendicular to the upper surface of the main plate 32 (i.e., axially relative to the rotational axis). In this disclosure, the term “perpendicular” includes both perpendicular and substantially perpendicular. - As shown in
FIGS. 6 and 7 , afront surface 38 a of theouter blade part 38 of theblade 36 extends from the upper surface of themain plate 32 obliquely rearward relative to the rotational direction of theimpeller 30. For instance, an angle formed between the upper surface of themain plate 32 and a lower end of thefront surface 38 a of theouter blade part 38 may be oblique. As shown inFIGS. 3 and 4 , thefront surface 37 a of theinner blade part 37 and thefront surface 38 a of theouter blade part 38 are contiguous with each other. As shown inFIGS. 6 and 7 , in the cross-sectional view perpendicular to a longitudinal direction of theouter blade part 38, thefront surface 38 a extends linearly between its upper end and a lower end in this embodiment. However, in other embodiments, thefront surface 38 a may be gently curved in a concave or convex manner in some embodiments. - In the cross-sectional view perpendicular to the longitudinal direction of the
outer blade part 38, thefront surface 38 a of theouter blade part 38 defines an includedangle 380 with a straight line L that extending perpendicular to the upper surface of themain plate 32 and passing through the upper end of thefront surface 38 a. That is, the includedangle 380 is formed by thefront surface 38 a and the straight line L and is acute. The includedangle 380 between thefront surface 38 a and the straight line L gradually increases from the radially inner end toward the radially outer end of theouter blade part 38. The direction along which the straight line L is disposed may also be referred to herein as an “axis disposed in the first direction.”. - As shown in
FIG. 4 , in the plan view of theimpeller 30, a lower half of thefront surface 38 a of the radially outer end of theouter blade part 38 is positioned in front of the radial vector N relative to the rotational direction R, and an upper half of this portion of thefront surface 38 a is positioned rearward of the radial vector N relative to the rotational direction R. Such a configuration is also illustrated inFIGS. 6 and 7 , in which a dashed line N′ shows a straight line extending vertically and perpendicular to the radial vector N. As shown inFIGS. 3 and 4 , a radially outer end surface of theouter blade part 38 is flush with an outer periphery of themain plate 32. A lower half of thefront surface 38 a may also be referred to herein as “a main plate side part.”, and the upper half of thefront surface 38 a may also be referred to herein as “an opposite side part”. The direction along which the radial vector N is disposed may also be referred to herein as a “normal axis.” - As shown in
FIGS. 6 and 7 , athickness 38 t of theouter blade part 38 in the rotational direction R gradually increases from the upper end toward the lower end of theouter blade part 38. Therear surface 38 b of theouter blade part 38 extends perpendicular to the upper surface of themain plate 32. As shown inFIG. 3 , therear surface 38 b of theouter blade part 38 is contiguous with therear surface 37 b of theinner blade part 37. As shown inFIG. 5 , athickness 37 t of theinner blade part 37 in the rotational direction R is constant between an upper end and a lower end of theinner blade part 37. In this disclosure, the term “constant” includes both constant and substantially constant. - In accordance with the first embodiment, the
front surface 38 a of theouter blade part 38 of eachblade 36 extends from the upper surface of themain plate 32 obliquely rearward relative to the rotational direction R Thus, as the radially outer end of eachouter blade part 38 comes close to thepartition wall 24, the radially outer end gradually decreases the opening area of the upstreamopen end 22 b of theoutlet port 22. Accordingly, a drastic increase in pressure can be suppressed, so that vibration and noise caused by pressure pulsations in thecentrifugal pump 10 can be decreased. - The included
angle 380 between thefront surface 38 a and the straight line L gradually increases from the radially inner end toward the radially outer end of theouter blade part 38. Such configuration of thefront surface 38 a can smoothen the fluid flow outward in the radial direction of theimpeller 30. - As shown in
FIG. 4 , in the plane view of theimpeller 30, the lower half of thefront surface 38 a of the radially outer end of eachouter blade part 38 is positioned in front of the radial vector N in the rotational direction R. Thus, the pressurizing performance of thecentrifugal pump 10 is increased, so that the number of revolution required for achieving a predetermined pressure can be decreased. In addition, the upper half of thefront surface 38 a of the radially outer end of eachouter blade part 38 is positioned rearward of the radial vector N relative to the rotational direction R. Such configuration can smoothen the fluid flow outward in the radial direction of theimpeller 30 so as to decrease a load torque on theimpeller 30. Accordingly, a decrease in both the number of revolution of thecentrifugal pump 10 and the load torque on theimpeller 30 is achieved, thereby improving pump efficiency. - The
thickness 38 t of eachouter blade part 38 gradually increases from the upper end toward the lower end of theouter blade part 38. Thus, the rigidity of theouter blade part 38 can be improved, thereby further reducing vibration and noise. - The
rear surface 38 b of eachouter blade part 38 extends upward from themain plate 32 in a direction perpendicular to the upper surface of themain plate 32. So, when theimpeller 30 is made from a resin material using molds, at least one of the molds, which shapes the correspondingrear surface 38 b, can be removed in the axial direction of theimpeller 30. Accordingly, the molds can be simplified, thereby improving manufacturing of theimpeller 30. - A second embodiment will be described with reference to
FIGS. 8 to 14 . The second embodiment is substantially the same as the first embodiment described above with some differences regarding theouter blade parts 38 of theimpeller 30. Thus, while the differences will be described, similar configurations will not be described in the interest of conciseness. - As shown in
FIGS. 9, 10, and 11 , each of theblades 36 includes a radiallyouter blade part 138 extending radially outward from the radial outer end of theinner blade part 37. In this embodiment, all of theouter blade parts 138 have substantially the same shape as each other. Accordingly, only one radiallyouter blade part 138 will be described with the understanding the other radiallyouter blade parts 138 are the same. Theouter blade part 138 includes afront surface 138 a extending from themain plate 32 of theimpeller 30 obliquely frontward relative to the rotational direction R of theimpeller 30. As shown inFIG. 12 , theinner blade part 37 of the second embodiment has the same shape as that of the first embodiment. - As shown in
FIGS. 13 and 14 , in the cross-sectional view perpendicular to the longitudinal direction of theouter blade part 138, an includedangle 1380 of thefront surface 138 a, which is defined by thefront surface 138 a and a straight line L that extends perpendicular to the upper surface of themain plate 32 and passes through the upper end of thefront surface 138 a, is acute. The includedangle 1380 formed between thefront surface 138 a and the straight line L gradually increases from the radially inner end toward the radially outer end of theouter blade part 138. - In
FIG. 11 , one radial vector N of theboss 34 is shown. The radial vector N passes through both therotation center 30 c of theimpeller 30 and a connection part between theinner blade part 37 and theouter blade part 138. In the plan view of theimpeller 30, an upper half of thefront surface 138 a of the radially outer end of theouter blade part 138 is positioned in front of the radial vector N relative to the rotational direction R of theimpeller 30, and a lower half of thefront surface 138 a of the radially outer end of theouter blade part 138 is positioned rearward of the radial vector N relative to the rotational direction R. - As shown in
FIGS. 13 and 14 , thethickness 138 t of theouter blade part 138 is constant between an upper end and a lower end of theouter blade part 138. In addition, thethickness 138 t is constant between the radially inner end and the radially outer end of theouter blade part 138, i.e. over the longitudinal whole length of theouter blade part 138. - As shown in
FIGS. 10 and 11 , an outer periphery of themain plate 32 is concave and curved radially inward between each pair ofadjacent blades 36, such that the radial length of themain plate 32 gradually decreases from a front of eachblade 36 toward theadjacent blade 36 in a direction opposite to the rotational direction R. Due to this configuration, themain plate 32 defines a plurality of circumferentially-spacedopenings 140 along the outer periphery thereof such that each of thefront surfaces 138 a of theouter blade part 138 faces acorresponding opening 140. - In accordance with the second embodiment, the
front surface 138 a of theouter blade part 138 of eachblade 36 of theimpeller 30 extends from the upper surface of themain plate 32 obliquely frontward relative to the rotational direction R of theimpeller 30. Thus, as the radially outer end of eachouter blade part 138 comes close to thepartition wall 24 of thehousing 11, which is illustrated inFIGS. 8 and 9 , the radially outer end gradually decreases the opening area of the upstreamopen end 22 b of theoutlet port 22. Accordingly, a drastic increase in pressure can be prevented, thereby decreasing vibration and noise caused by pressure pulsations of thecentrifugal pump 10. - The included
angle 1380 formed between thefront surface 138 a and the straight line L gradually increases from the radially inner end toward the radially outer end of theouter blade part 138. Such configuration of theouter blade part 138 can smoothen the fluid flow outward in the radial direction of theimpeller 30. - In the plan view of the
impeller 30, the upper half of thefront surface 138 a of the radially outer end of eachouter blade part 138 is positioned in front of the radial vector N in the rotational direction R. Thus, pressurizing performance of thecentrifugal pump 10 is increased, so that the number of revolution required for achieving a predetermined pressure can be decreased. In addition, the lower half of thefront surface 138 a of the radially outer end of eachouter blade part 138 is positioned rearward of the radial vector N in the rotational direction R. Such configuration can smoothen the fluid flow outward in the radial direction of theimpeller 30 so as to decrease a load torque on theimpeller 30. Accordingly, a decrease in both the number of revolution of thecentrifugal pump 10 and the load torque on theimpeller 30 is achieved, thereby improving pump efficiency. - The
main plate 32 defines theopenings 140 that thefront surfaces 138 a of theouter blade parts 138 face. So, when theimpeller 30 is made from a resin material using molds, at least one of the molds, shaping the correspondingfront surface 138 a, can be removed in the axial direction of theimpeller 30. Accordingly, the mold can be simplified, thereby improving manufacturing of theimpeller 30. - A third embodiment will be described with reference to
FIG. 15 . The third embodiment is substantially the same as the second embodiment described above with some modifications regarding theouter blade parts 138 of theimpeller 30. Thus, while the differences will be described, similar configurations will not be described in the interest of conciseness. - As shown in
FIG. 15 , a radiallyouter blade part 238 of eachblade 36 includes afront surface 238 a formed with a similar configuration as thefront surface 138 a of the second embodiment. However, theouter blade part 238 is also shaped such that its thickness 238 f in the rotational direction R gradually increases from the upper end toward the lower end of theouter blade part 238. Thus, the rigidity of theouter blade parts 238 can be increased, thereby reducing vibration and breakage of theouter blade parts 238. - A fourth embodiment will be described with reference to
FIG. 16 . The fourth embodiment is substantially the same as the first embodiment described above with some modifications regarding theouter blade parts 38 of theimpeller 30. Thus, while the differences will be described, similar configurations will not be described in the interest of conciseness. - As shown in
FIG. 16 , each radiallyouter blade part 338 of theimpeller 30 includes afront surface 338 a formed with a similar configuration as thefront surface 38 a of the first embodiment. However, thethickness 338 t of theouter blade part 338 is constant between an upper end and a lower end of theouter blade part 338. That is, arear surface 338 a of eachouter blade part 338 faces obliquely downward relative to the rotational direction R. - Although not shown in the drawings, an outer periphery of a
main plate 332 is concave and curved radially inward between each pair of circumferentiallyadjacent blades 36, such that the radial length of themain plate 332 gradually increases from a front of oneblade 36 toward anadjacent blade 36. Due to this configuration, themain plate 332 of theimpeller 30 defines a plurality of circumferentially-spacedopenings 340 along the outer periphery thereof, such that each of therear surfaces 338 b of theouter blade part 338 faces thecorresponding opening 340. Thus, when theimpeller 30 is made from a resin material using molds, at least one of the molds, shaping the correspondingrear surface 338 b, can be removed in the axial direction of theimpeller 30. Accordingly, the molds can be simplified, thereby improving manufacturing of theimpeller 30. - As mentioned above, the apparatus and methods disclosed in this application are not limited to the above-described embodiments. For example, the
centrifugal pump 10 may be used for pumping various fluid, such as air, other than a purge gas. The brushless motor of themotor section 14 may be replaced with a brushed motor. Thecentrifugal pump 10 may be comprised of themotor section 14 only such that therotational shaft 15 is rotated by a driving source that is provided outside thecentrifugal pump 10. Theimpeller 30 may be made from a metal material.
Claims (10)
1. A centrifugal pump, comprising:
an impeller configured to be rotated in a rotational direction about a rotational axis by a motor, wherein the impeller includes a main plate and a plurality of blades, wherein the main plate has a substantially circular shape and a first surface, wherein each of the blades extends axially from the first surface of the main plate and radially along the first surface of the main plate; and
a housing defining a pump chamber that houses the impeller therein, wherein the housing includes an inlet port configured to supply a fluid into the pump chamber axially toward a center of the first surface of the main plate and an outlet port configured to discharge the fluid in a tangential direction from the pump chamber, wherein:
each of the blades has a radially inner blade part and a radially outer blade part extending radially outward from the radially inner blade part, and
each of the radially outer blade parts has a front surface that extends from the main plate obliquely rearward relative to the rotational direction.
2. The centrifugal pump of claim 1 , wherein:
an angle of the front surface of one of the radially outer blade parts relative to a straight line extending in parallel with the rotational axis is acute and continuously increases moving radially outward.
3. The centrifugal pump of claim 1 , wherein:
one of the radially outer blade parts includes a radially outer end that is divided into a main plate side part adjacent to the main plate and an opposite side part positioned away from the main plate,
a reference line passes radially through both the rotational axis of the impeller and a radially inner end of the one of the radially outer blade parts,
the main plate side part is positioned in front of the reference line relative to the rotational direction, and
the opposite side part is positioned rearward of the reference line relative to the rotational direction.
4. The centrifugal pump of claim 1 , wherein:
a thickness in the rotational direction of each of the radially outer blade parts continuously increases moving axially toward the first surface.
5. The centrifugal pump of claim 4 , wherein:
each of the radially outer blade parts has a rear surface extending perpendicular to the main plate or extends obliquely rearward relative to the rotational direction.
6. A centrifugal pump, comprising:
an impeller configured to be rotated about a rotational axis in a rotational direction by a motor, wherein the impeller includes a main plate and a plurality of blades, wherein the main plate has a substantially circular shape and a first surface, wherein each of the blades projects axially from the first surface of the main plate and extends radially along the first surface of the main plate; and
a housing defining a pump chamber that houses the impeller therein, wherein the housing includes an inlet port configured to supply a fluid into the pump chamber axially toward a center of the first surface of the main plate and an outlet port configured to discharge the fluid from the pump chamber in a tangential direction, wherein:
each of the blades has a radially inner blade part and a radially outer blade part that extends radially outward from the radially inner blade part, and
each of the radially outer blade parts has a front surface that extends from the main plate obliquely frontward relative to the rotational direction.
7. The centrifugal pump of claim 6 , wherein:
an angle of the front surface of one of the radially outer blade parts relative to a straight line extending in parallel with the rotational axis is acute and continuously increases moving radially outward.
8. The centrifugal pump of claim 6 , wherein:
one of the radially outer blade parts includes a radially outer end having a main plate side part adjacent to the main plate and an opposite side part positioned away from the main plate,
a reference line passes radially through both the rotational axis of the impeller and a radially inner end of the one of the radially outer blade parts,
the main plate side part is positioned rearward of the reference line relative to the rotational direction, and
the opposite side part is positioned in front of the reference line relative to the rotational direction.
9. The centrifugal pump of claim 6 , wherein:
a thickness in the rotational direction of each of the radially outer blade parts continuously increases moving axially toward the first surface.
10. The centrifugal pump of claim 9 , wherein:
an outer periphery of the main plate is curved radially inward between a pair of circumferentially adjacent blades to define an opening along the outer periphery of the main plate, and
the front surface of the radially outer blade part of a rear one of the pair of circumferentially adjacent blades relative to the rotational direction faces the opening.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2019029401A JP2020133534A (en) | 2019-02-21 | 2019-02-21 | Centrifugal pump |
JP2019-029401 | 2019-02-21 |
Publications (1)
Publication Number | Publication Date |
---|---|
US20200271127A1 true US20200271127A1 (en) | 2020-08-27 |
Family
ID=72142859
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US16/790,893 Abandoned US20200271127A1 (en) | 2019-02-21 | 2020-02-14 | Centrifugal Pump |
Country Status (3)
Country | Link |
---|---|
US (1) | US20200271127A1 (en) |
JP (1) | JP2020133534A (en) |
CN (1) | CN111594483A (en) |
Family Cites Families (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3482668B2 (en) * | 1993-10-18 | 2003-12-22 | 株式会社日立製作所 | Centrifugal fluid machine |
CN2213877Y (en) * | 1994-09-24 | 1995-11-29 | 孙敏超 | Back bend impeller |
FR2802579B1 (en) * | 1999-12-21 | 2002-06-14 | Jeumont Ind | BLADE OF A CENTRIFUGAL MACHINE AND METHOD FOR ADJUSTING BLADE PERFORMANCE |
CN1189666C (en) * | 2002-06-06 | 2005-02-16 | 孙敏超 | Efficient propeller with blades curled backward for centrifugal propeller machinery |
JP2005282500A (en) * | 2004-03-30 | 2005-10-13 | Toshiba Corp | Fluid pump, cooling device and electric apparatus |
JP4540379B2 (en) * | 2004-03-31 | 2010-09-08 | 米原技研有限会社 | Pressurized centrifugal pump |
JP2006257978A (en) * | 2005-03-17 | 2006-09-28 | Aisin Seiki Co Ltd | Fluid pump |
CN101865145B (en) * | 2009-04-20 | 2012-09-19 | 日立空调·家用电器株式会社 | Electric blower, electric dust collector carrying the same and manufacturing method thereof |
JP5879103B2 (en) * | 2011-11-17 | 2016-03-08 | 株式会社日立製作所 | Centrifugal fluid machine |
CN202732465U (en) * | 2012-06-14 | 2013-02-13 | 浙江超越实业有限公司 | Fan flywheel for gasoline engine |
JP5705945B1 (en) * | 2013-10-28 | 2015-04-22 | ミネベア株式会社 | Centrifugal fan |
JP2016084751A (en) * | 2014-10-27 | 2016-05-19 | 三菱重工業株式会社 | Impeller, centrifugal fluid machine and fluid device |
JP2018105268A (en) * | 2016-12-28 | 2018-07-05 | 日本電産株式会社 | Blowing device and cleaner equipped with the same |
CN206636828U (en) * | 2017-02-23 | 2017-11-14 | 苏州工业园区星德胜电机有限公司 | A kind of small size mixed-flow impeller |
-
2019
- 2019-02-21 JP JP2019029401A patent/JP2020133534A/en active Pending
-
2020
- 2020-02-14 US US16/790,893 patent/US20200271127A1/en not_active Abandoned
- 2020-02-21 CN CN202010108596.2A patent/CN111594483A/en not_active Withdrawn
Also Published As
Publication number | Publication date |
---|---|
CN111594483A (en) | 2020-08-28 |
JP2020133534A (en) | 2020-08-31 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US7500825B2 (en) | Centrifugal blower | |
JP6067095B2 (en) | Centrifugal compressor | |
TWI460352B (en) | Electric blower and equipped with its electric vacuum cleaner | |
KR940015292A (en) | Regeneration Pump and Impeller Manufacturing Method | |
US10605264B2 (en) | Diffuser, airflow generating apparatus, and electrical device | |
HU218759B (en) | Pump, especially fuel pump, and pumpshell for such pumps | |
JPH07197896A (en) | Fuel pump for automobile | |
US20180258959A1 (en) | Vaned Diffuser and Blower, Fluid Machine, or Electric Blower Provided with Same | |
US7241114B2 (en) | Rotor for a centrifugal pump | |
JP2004353655A (en) | Radial impeller | |
US20210102551A1 (en) | Electric compressor | |
US20200271127A1 (en) | Centrifugal Pump | |
KR101177293B1 (en) | Turbine fuel pump for vehicle | |
TW201542155A (en) | Centrifugal blower and electric vacuum cleaner | |
US6942447B2 (en) | Impeller pumps | |
US20200291954A1 (en) | Centrifugal Pump | |
US20200291956A1 (en) | Centrifugal Pump | |
US5364238A (en) | Divergent inlet for an automotive fuel pump | |
JP2008542612A (en) | Pumping unit | |
JP6687108B2 (en) | Turbine housing and supercharger | |
KR101222017B1 (en) | Impeller of fuel pump for vehicle | |
US6302639B1 (en) | Feed pump | |
JP6635255B2 (en) | Inlet guide vane, compressor, method of mounting inlet guide vane, and method of manufacturing centrifugal compressor | |
US9903388B2 (en) | Centrifugal pump | |
JP6138009B2 (en) | Centrifugal turbomachine |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: AISAN KOGYO KABUSHIKI KAISHA, JAPAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:HONDA, YOSHIHIKO;SUZUKI, HIRONORI;REEL/FRAME:051819/0503 Effective date: 20200204 |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: APPLICATION DISPATCHED FROM PREEXAM, NOT YET DOCKETED |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: DOCKETED NEW CASE - READY FOR EXAMINATION |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: NON FINAL ACTION MAILED |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |