US20040146422A1 - Pump - Google Patents
Pump Download PDFInfo
- Publication number
- US20040146422A1 US20040146422A1 US10/712,210 US71221003A US2004146422A1 US 20040146422 A1 US20040146422 A1 US 20040146422A1 US 71221003 A US71221003 A US 71221003A US 2004146422 A1 US2004146422 A1 US 2004146422A1
- Authority
- US
- United States
- Prior art keywords
- screw
- idler
- edge portion
- longitudinal axis
- land surface
- 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
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C2/00—Rotary-piston machines or pumps
- F04C2/08—Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing
- F04C2/12—Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type
- F04C2/14—Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type with toothed rotary pistons
- F04C2/16—Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type with toothed rotary pistons with helical teeth, e.g. chevron-shaped, screw type
- F04C2/165—Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type with toothed rotary pistons with helical teeth, e.g. chevron-shaped, screw type having more than two rotary pistons with parallel axes
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C2/00—Rotary-piston machines or pumps
- F04C2/08—Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing
- F04C2/082—Details specially related to intermeshing engagement type machines or pumps
- F04C2/084—Toothed wheels
Definitions
- the present invention relates to a pump particularly to a pump including a power screw and at least one idler screw mounted in a housing, the idler screw which meshes with the power screw such that rotation of the power screw causes rotation of the idler screw.
- Such a pump is commonly known as a screw pump, and pumping of fluid within the housing is effected by fluid becoming trapped and pressurised between the meshing screws.
- such pumps typically include one or two cylindrical idler screws. Where two idler screws are provided they are typically mounted on diametrically opposite sides of the power screw.
- the idler screws need not be attached to the housing but may simply be retained within the housing.
- the idler screws may be mounted at an end in a bearing provided in the housing. In both cases, the pressure from the pumped fluid exerts a force on the idler screws which tends to push the idler screws away from the power screw into the housing. As a result, frictional forces between the idler screws and the housing can cause significant energy losses. This is a particular problem when the idler screws are not mounted in a bearing.
- a pump including a power screw and at least one idler screw which meshes with the power screw, the power screw and idler screw being rotatable in a housing, the idler screw having at least one screw form including a generally helical groove and a generally helical land surface, the land surface having a first and a second edge portion, each of which is adjacent to the or a groove, the distance between the land surface and a longitudinal axis of the idler screw varying between the first edge portion and the second edge portion, the distance between the first edge portion and the longitudinal axis of the idler screw being substantially constant over the length of the screw form and the distance between the second edge portion and the longitudinal axis of the idler screw being substantially constant over the length of the screw form.
- the pumped fluid acts as a hydrodynamic bearing, supporting the idler screw and reducing the frictional forces between the idler screw and the housing.
- the distance between the or the at least one land surface and the longitudinal axis increases continuously from the first edge portion to the second edge portion.
- the distance between the or the at least one land surface and the longitudinal axis initially increases from the first edge portion to a position intermediate the first and second edge portions, and then remains generally constant from the intermediate position to the second edge portion.
- the intermediate position may be approximately half way between the first and second portions.
- Such an arrangement may be easier to manufacture and gauge than where the distance increases continuously.
- the hydrodynamic pressure drop between where the second edge portion separates from the adjacent housing wall as the idler screw rotates, and where the next first edge portion engages the housing wall is reduced compared within a continuously ramped arrangement.
- the idler screw is arranged so that the first edge portion leads the second edge portion as the idler screw rotates in use.
- the first and/or second edge portion may be slightly radiussed if desired so as to provide a lead-in to the or an adjacent groove.
- the power screw includes at least one generally helical ridge which engages with the generally helical groove of the or each idler screw.
- each idler screw includes two generally helical grooves of substantially the same pitch and two generally helical land surfaces, each land surface having a first and a second edge portion, each of which is adjacent to a groove, the distance between each land surface and a longitudinal axis of the idler screw varying between the first edge portion and the second edge portion over at least part of the length of the idler screw.
- the power screw includes two generally helical ridges of substantially the same pitch.
- the pump includes two idler screws located at diametrically opposite sides of the power screw.
- the difference in the distance between the longitudinal axis of the idler screw and the land surface at the first edge portion and the second edge portion may be up to 4% of the largest distance between the longitudinal axis of the idler screw and the land surface.
- An end of the or each idler screw may be mounted in a bearing provided in the housing.
- FIG. 1 is an illustration of a power screw and idler screws and a housing of a pump according to the invention
- FIG. 2 is an illustration of a transverse cross-section through the power screw and idler screws of FIG. 1.
- FIG. 2 a is a view similar to FIG. 2 but showing a preferred idler screw form
- FIG. 3 is an illustration of a longitudinal section through a pump according to the invention, in the direction shown by arrow X in FIG. 2.
- FIG. 4 is an illustration of a longitudinal section through a pump according to the invention in the direction shown by arrow Y in FIG. 2.
- a power screw 10 and idler screws 12 of a screw pump the two idler screws 12 located at diametrically opposite sides of the power screw 10 .
- Longitudinal axes A of the idler screws 12 are generally parallel to the longitudinal axis B of the power screw 10 .
- Each idler screw 12 has two screw forms which include first and second generally helical grooves 14 , 14 ′ which each extend along substantially the entire length of the screw 12 .
- the two grooves 14 , 14 ′ are both of substantially the same pitch and sense, and the turns of the grooves 14 , 14 ′ are interposed such that when the screw 12 is viewed in transverse cross-section one groove 14 is diametrically opposite the other 14 ′.
- the grooves 14 , 14 ′ are separated by first and second generally helical land surfaces 16 , 16 ′, each land surface having a first edge portion 16 a , 16 a ′ and second edge portion 16 b , 16 b ′ adjacent to one of the grooves 14 , 14 ′.
- the first edge portion 16 a of the first land surface 16 is adjacent to the second groove 14 ′ and the second edge portion 16 b of the first land surface 16 is adjacent to the first groove 14 .
- the first edge portion 16 a ′ of the second land surface 16 ′ is adjacent to the first groove 14
- the second edge portion 16 b ′ of the second land surface 16 ′ is adjacent to the second groove 14 ′.
- each land surface 16 , 16 ′ and the longitudinal axis A of the idler screw 12 increases continuously from the first edge portion 16 a , 16 a ′ to the second edge portion 16 b , 16 b′.
- the distance between each land surface 16 , 16 ′ and the longitudinal axis A of the idler screw 12 increases from the first edge portion 16 , 16 a ′ continuously to an intermediate position I, I′, which intermediate position I, I′ is in this example, approximately half way between the respective first and second edge portions 16 a , 16 a ′; 16 b , 16 b ′. From the intermediate positions I, I′ to the second edge portions 16 b , 16 b ′, the distance between the land surface 16 , 16 ′ and the longitudinal axis A of the idler screw 12 is generally constant.
- first and/or second edge portions 16 a , 16 a ′; 16 b , 16 b ′ may be slightly radiussed so as to provide a lead-in to the adjacent respective groove 14 , 14 ′.
- the difference in the distance between the first edge portion 16 a , 16 a ′ of each land surface 16 , 16 ′ and the longitudinal axis A and the distance between the second edge portion 16 b , 16 b ′ of each land surface 16 , 16 ′ and the longitudinal axis A is up to 4% of the largest outside diameter of the idler screw 12 , i.e. the distance between the second edge portion 16 b , 16 b ′ of each land surface 16 , 16 ′ and the longitudinal axis A.
- this difference has been exaggerated in FIGS. 2 and 2 a for clarity.
- the power screw 10 and idler screw 12 are both generally cylindrical, however, and thus it will be appreciated that the distance between each first edge portion 16 a , 16 a ′ and the longitudinal axis A of the idler screw 12 is substantially constant over the length of the idler screw 12 , as is the distance between each second edge portion 16 b , 16 b ′ and the longitudinal axis A.
- the power screw 10 is provided with first 18 and second 18 ′ generally helical ridges which each extend along substantially the entire length of the screw 10 .
- the two ridges 18 , 18 ′ are both of substantially the same pitch & sense, and the turns of the ridges 18 , 18 ′ are interposed such that when the screw 10 is viewed in transverse cross-section, one ridge 18 is diametrically opposite the other 18 ′.
- the first ridge 18 meshes with the first groove 14 of each idler screw 12
- the second ridge 18 ′ meshes with the second groove 14 ′ of each idler screw 12 , and thus rotation of the power screw 10 about its longitudinal axis B in the direction indicated by the respective arrow, causes rotation of the idler screws 12 about their longitudinal axes A in the opposite rotational direction as indicated by the respective arrows.
- the power screw 10 and idler screws 12 are mounted in a housing 20 , part of which is illustrated in FIGS. 2 and 2 a , 3 & 4 , which is shaped to provide minimum clearance between the screws 10 , 12 and the housing 20 , whilst permitting rotation of the screws 10 , 12 within the housing 20 .
- the housing 20 thus includes an elongate cavity in which the screws 10 , 12 are housed.
- the cavity includes a central part circular portion 20 a of a larger diameter adapted to house the power screw 10 , and two part circular lobe portions 20 b located on diametrically opposite sides of the central portion of 20 a , which each have a smaller diameter and are adapted to house the idler screws 12 .
- the housing 20 also includes an outlet port 22 and an inlet port 24 , the inlet port 24 being arranged such that fluid enters the cavity adjacent to first ends of the driven and idler screws 10 , 12 and the outlet port 22 being arranged such that fluid leaves the cavity adjacent to second ends of the driven and idler screws 10 , 12 .
- the inlet port 24 is connected to a supply of fluid to be pumped.
- the power screw 10 is connected to a motor (not shown) by means of a drive shaft 26 , the drive shaft 26 being mounted in bearings 28 provided in the housing 20 . Operation of the motor causes the power screw 10 to rotate about its longitudinal axis B in a first sense, and which thus causes the idler screws 12 each to rotate about their longitudinal axes A in an opposite sense to the power screw 10 .
- the screws 10 , 12 are oriented such their rotation causes fluid to be drawn from the inlet port and moved along the length of the screws 10 , 12 to the outlet port.
- Fluid trapped between the ridges 18 , 18 ′ and the grooves 14 , 14 ′ as the screws 10 , 12 mesh becomes pressurised and exerts an outward force on both the idler screws 12 , which tends to push the idler screws 12 towards the housing 20 .
- the idler screws 12 are configured such that the first edge portions 16 a , 16 a ′ of each land surface 16 , 16 ′ lead the second edge portions 16 b , 16 b ′ as the idler screws 12 rotate.
- the resulting change in separation between the land surfaces 16 , 16 ′ and the housing 20 compresses the fluid between the housing 20 and the land surfaces 16 , 16 ′, the resultant local fluid pressures enable the fluid to act as a hydrodynamic bearing, supporting the idler screws 12 , and reducing frictional forces between the housing and the land surfaces 16 , 16 ′ of the idler screws 12 .
- the efficiency of the pump is improved.
- Such a pump advantageously is used to pump fluid for hydraulic systems which may include actuators.
- the idler screws 12 are not connected to the housing 20 , but it is possible to mount the idler screws 12 on bearings connected to the housing 20 .
- each idler screw 12 may be provided with one or more than two grooves 14 , 14 ′, and the power screw 10 provided with a corresponding number of ridges 18 , 18 ′.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Rotary Pumps (AREA)
Abstract
A pump includes a power screw and at least one idler screw which meshes with the power screw, the power screw and idler screw being rotatable in a housing, the idler screw having at least one screw form including a generally helical groove and a generally helical land surface, the land surface having a first, and a second edge portion, each of which is adjacent to the or a groove, the distance between the land surface and a longitudinal axis of the idler screw varying between the first edge portion and the second edge portion, the distance between the first edge portion and the longitudinal axis of the idler screw being substantially constant over the length of the screw form and the distance between the second edge portion and the longitudinal axis of the idler screw being substantially constant over the length of the screw form.
Description
- This application claims priority to United Kingdom Patent Application No. 0226529.6 filed Nov. 14, 2002, the entire disclosure of which is incorporated herein by reference.
- The present invention relates to a pump particularly to a pump including a power screw and at least one idler screw mounted in a housing, the idler screw which meshes with the power screw such that rotation of the power screw causes rotation of the idler screw.
- Such a pump is commonly known as a screw pump, and pumping of fluid within the housing is effected by fluid becoming trapped and pressurised between the meshing screws.
- Typically, such pumps include one or two cylindrical idler screws. Where two idler screws are provided they are typically mounted on diametrically opposite sides of the power screw. The idler screws need not be attached to the housing but may simply be retained within the housing. Alternatively, the idler screws may be mounted at an end in a bearing provided in the housing. In both cases, the pressure from the pumped fluid exerts a force on the idler screws which tends to push the idler screws away from the power screw into the housing. As a result, frictional forces between the idler screws and the housing can cause significant energy losses. This is a particular problem when the idler screws are not mounted in a bearing.
- According to the invention a pump including a power screw and at least one idler screw which meshes with the power screw, the power screw and idler screw being rotatable in a housing, the idler screw having at least one screw form including a generally helical groove and a generally helical land surface, the land surface having a first and a second edge portion, each of which is adjacent to the or a groove, the distance between the land surface and a longitudinal axis of the idler screw varying between the first edge portion and the second edge portion, the distance between the first edge portion and the longitudinal axis of the idler screw being substantially constant over the length of the screw form and the distance between the second edge portion and the longitudinal axis of the idler screw being substantially constant over the length of the screw form.
- By virtue of the shape of the idler screw, the pumped fluid acts as a hydrodynamic bearing, supporting the idler screw and reducing the frictional forces between the idler screw and the housing.
- In one embodiment, the distance between the or the at least one land surface and the longitudinal axis increases continuously from the first edge portion to the second edge portion. In a preferred embodiment, the distance between the or the at least one land surface and the longitudinal axis, initially increases from the first edge portion to a position intermediate the first and second edge portions, and then remains generally constant from the intermediate position to the second edge portion. The intermediate position may be approximately half way between the first and second portions. Such an arrangement may be easier to manufacture and gauge than where the distance increases continuously. Also in use, the hydrodynamic pressure drop between where the second edge portion separates from the adjacent housing wall as the idler screw rotates, and where the next first edge portion engages the housing wall is reduced compared within a continuously ramped arrangement.
- In each case, preferably the idler screw is arranged so that the first edge portion leads the second edge portion as the idler screw rotates in use.
- The first and/or second edge portion may be slightly radiussed if desired so as to provide a lead-in to the or an adjacent groove.
- Preferably the power screw includes at least one generally helical ridge which engages with the generally helical groove of the or each idler screw.
- Preferably, each idler screw includes two generally helical grooves of substantially the same pitch and two generally helical land surfaces, each land surface having a first and a second edge portion, each of which is adjacent to a groove, the distance between each land surface and a longitudinal axis of the idler screw varying between the first edge portion and the second edge portion over at least part of the length of the idler screw. In this case, the power screw includes two generally helical ridges of substantially the same pitch.
- Preferably the pump includes two idler screws located at diametrically opposite sides of the power screw.
- The difference in the distance between the longitudinal axis of the idler screw and the land surface at the first edge portion and the second edge portion may be up to 4% of the largest distance between the longitudinal axis of the idler screw and the land surface.
- An end of the or each idler screw may be mounted in a bearing provided in the housing.
- Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, of which,
- FIG. 1 is an illustration of a power screw and idler screws and a housing of a pump according to the invention,
- FIG. 2 is an illustration of a transverse cross-section through the power screw and idler screws of FIG. 1.
- FIG. 2a is a view similar to FIG. 2 but showing a preferred idler screw form;
- FIG. 3 is an illustration of a longitudinal section through a pump according to the invention, in the direction shown by arrow X in FIG. 2.
- FIG. 4 is an illustration of a longitudinal section through a pump according to the invention in the direction shown by arrow Y in FIG. 2.
- Referring now to the figures, there is shown a
power screw 10 andidler screws 12 of a screw pump, the twoidler screws 12 located at diametrically opposite sides of thepower screw 10. Longitudinal axes A of theidler screws 12 are generally parallel to the longitudinal axis B of thepower screw 10. Eachidler screw 12 has two screw forms which include first and second generallyhelical grooves screw 12. The twogrooves grooves screw 12 is viewed in transverse cross-section onegroove 14 is diametrically opposite the other 14′. - The
grooves helical land surfaces first edge portion second edge portion grooves first edge portion 16 a of thefirst land surface 16 is adjacent to thesecond groove 14′ and thesecond edge portion 16 b of thefirst land surface 16 is adjacent to thefirst groove 14. Thefirst edge portion 16 a′ of thesecond land surface 16′ is adjacent to thefirst groove 14, and thesecond edge portion 16 b′ of thesecond land surface 16′ is adjacent to thesecond groove 14′. - In the FIG. 2 embodiment, the distance between each
land surface idler screw 12 increases continuously from thefirst edge portion second edge portion - In the embodiment of FIG. 2a, on which all like parts to those on FIG. 2 are labelled with the same references, the distance between each
land surface idler screw 12 increases from thefirst edge portion second edge portions second edge portions land surface idler screw 12 is generally constant. - In each example, if desired, the first and/or
second edge portions respective groove - Typically, the difference in the distance between the
first edge portion land surface second edge portion land surface idler screw 12, i.e. the distance between thesecond edge portion land surface - The
power screw 10 andidler screw 12 are both generally cylindrical, however, and thus it will be appreciated that the distance between eachfirst edge portion idler screw 12 is substantially constant over the length of theidler screw 12, as is the distance between eachsecond edge portion - The
power screw 10 is provided with first 18 and second 18′ generally helical ridges which each extend along substantially the entire length of thescrew 10. The tworidges ridges screw 10 is viewed in transverse cross-section, oneridge 18 is diametrically opposite the other 18′. - The
first ridge 18 meshes with thefirst groove 14 of eachidler screw 12, and thesecond ridge 18′ meshes with thesecond groove 14′ of eachidler screw 12, and thus rotation of thepower screw 10 about its longitudinal axis B in the direction indicated by the respective arrow, causes rotation of theidler screws 12 about their longitudinal axes A in the opposite rotational direction as indicated by the respective arrows. - The
power screw 10 andidler screws 12 are mounted in ahousing 20, part of which is illustrated in FIGS. 2 and 2a, 3 & 4, which is shaped to provide minimum clearance between thescrews housing 20, whilst permitting rotation of thescrews housing 20. Thehousing 20 thus includes an elongate cavity in which thescrews circular portion 20 a of a larger diameter adapted to house thepower screw 10, and two partcircular lobe portions 20 b located on diametrically opposite sides of the central portion of 20 a, which each have a smaller diameter and are adapted to house theidler screws 12. - As illustrated in FIGS. 3 & 4, the
housing 20 also includes anoutlet port 22 and aninlet port 24, theinlet port 24 being arranged such that fluid enters the cavity adjacent to first ends of the driven andidler screws outlet port 22 being arranged such that fluid leaves the cavity adjacent to second ends of the driven andidler screws inlet port 24 is connected to a supply of fluid to be pumped. - The
power screw 10 is connected to a motor (not shown) by means of adrive shaft 26, thedrive shaft 26 being mounted inbearings 28 provided in thehousing 20. Operation of the motor causes thepower screw 10 to rotate about its longitudinal axis B in a first sense, and which thus causes theidler screws 12 each to rotate about their longitudinal axes A in an opposite sense to thepower screw 10. Thescrews screws ridges grooves screws idler screws 12, which tends to push theidler screws 12 towards thehousing 20. - The
idler screws 12 are configured such that thefirst edge portions land surface second edge portions idler screws 12 rotate. The resulting change in separation between theland surfaces housing 20 compresses the fluid between thehousing 20 and theland surfaces idler screws 12, and reducing frictional forces between the housing and theland surfaces idler screws 12. Thus, the efficiency of the pump is improved. - Such a pump advantageously is used to pump fluid for hydraulic systems which may include actuators.
- In the examples described, the idler screws12 are not connected to the
housing 20, but it is possible to mount the idler screws 12 on bearings connected to thehousing 20. - It is not necessary to provide each
idler screw 12 with twogrooves power screw 10 with tworidges idler screw 12 may be provided with one or more than twogrooves power screw 10 provided with a corresponding number ofridges
Claims (12)
1. A pump including a power screw and at least one idler screw which meshes with the power screw, the power screw and idler screw being rotatable in a housing, the idler screw having at least one screw form including a generally helical groove and a generally helical land surface, the land surface having a first and a second edge portion, each of which is adjacent to the or a groove, the distance between the land surface and a longitudinal axis of the idler screw varying between the first edge portion and the second edge portion, the distance between the first edge portion and the longitudinal axis of the idler screw being substantially constant over the length of the screw form and the distance between the second edge portion and the longitudinal axis of the idler screw being substantially constant over the length of the screw form.
2. A pump according to claim 1 wherein the distance between the or the at least one land surface and a longitudinal axis increases continuously from the first edge portion to the second edge portion.
3. A pump according to claim 1 wherein the distance between the or at least one land surface and the longitudinal axis initially increases from the first edge portion to a position intermediate the first and second edge portions, and then remains generally constant from the intermediate position to the second edge portion.
4. A pump according to claim 3 wherein the intermediate position is approximately half-way between the first and second edge portions.
5. A pump according to claim 1 wherein the idler screw is arranged so that the first edge portion leads the second edge portion as the idler screw rotates in use.
6. A pump according to claim 1 wherein the first and/or the second edge portions include a radiussed lead-in to the or an adjacent groove.
7. A pump according to claim 1 wherein the power screw includes at least one generally helical ridge which engages with the generally helical groove of the or each idler screw.
8. A pump according to claim 1 wherein each idler screw includes two generally helical grooves of substantially the same pitch and two generally helical land surfaces, each land surface having a first and a second edge portion, each of which is adjacent to a groove, the distance between each land surface and a longitudinal axis of the idler screw varying between the first edge portion and the second edge portion over at least part of the length of the idler screw.
9. A pump according to claim 8 wherein the power screw includes two generally helical ridges of substantially the same pitch.
10. A pump according to claim 1 wherein the pump includes two idler screws located at diametrically opposite sides of the power screw.
11. A pump according to claim 1 wherein the difference in the distance between the longitudinal axis of the idler screw and the land surface at the first edge portion and the second edge portion is up to 4% of the largest distance between the longitudinal axis of the idler screw and the land surface.
12. A pump according to claim 1 wherein an end of the or each idler screw is mounted in a bearing provided in the housing.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB0226529.6 | 2002-11-14 | ||
GBGB0226529.6A GB0226529D0 (en) | 2002-11-14 | 2002-11-14 | Pump |
Publications (1)
Publication Number | Publication Date |
---|---|
US20040146422A1 true US20040146422A1 (en) | 2004-07-29 |
Family
ID=9947786
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/712,210 Abandoned US20040146422A1 (en) | 2002-11-14 | 2003-11-13 | Pump |
Country Status (2)
Country | Link |
---|---|
US (1) | US20040146422A1 (en) |
GB (2) | GB0226529D0 (en) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7152274B2 (en) | 2003-04-17 | 2006-12-26 | The Hoover Company | Handle and latch for a removable dirt separation system |
WO2022225485A2 (en) * | 2021-04-21 | 2022-10-27 | Repg Enerji Sistemleri Sanayi Ve Ticaret Anonim Sirketi | A screwed generator which uses heat transfer method for generating energy |
Citations (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2588888A (en) * | 1949-02-08 | 1952-03-11 | Laval Steam Turbine Co | Pump |
US3247580A (en) * | 1962-05-09 | 1966-04-26 | Laval Turbine | Method of making screw pumps |
US3289600A (en) * | 1964-03-13 | 1966-12-06 | Joseph E Whitfield | Helically threaded rotors for screw type pumps, compressors and similar devices |
US3291061A (en) * | 1963-07-23 | 1966-12-13 | Kosaka Kenkyusho Ltd | Screw pump or hydraulic screw motor |
US4405286A (en) * | 1982-01-21 | 1983-09-20 | The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration | Actively suspended counter-rotating machine |
US5066205A (en) * | 1989-05-19 | 1991-11-19 | Excet Corporation | Screw rotor lobe profile for simplified screw rotor machine capacity control |
US5123821A (en) * | 1990-03-08 | 1992-06-23 | Allweiler Ag | Screw spindle pump with a reduced pulsation effect |
US5911743A (en) * | 1997-02-28 | 1999-06-15 | Shaw; David N. | Expansion/separation compressor system |
US5934891A (en) * | 1995-06-22 | 1999-08-10 | Kone Oy | Constant leakage flow, pulsation free screw pump |
US6019586A (en) * | 1998-01-20 | 2000-02-01 | Sunny King Machinery Co., Ltd. | Gradationally contracted screw compression equipment |
US6139297A (en) * | 1995-12-11 | 2000-10-31 | Ateliers Busch S.A. | Double worm system |
US6158996A (en) * | 1996-09-12 | 2000-12-12 | Ateliers Busch S.A. | Screw rotor set |
US6257854B1 (en) * | 2000-02-02 | 2001-07-10 | Industrial Technology Research Institute | Double screw rotor assembly having means to automatically adjust the clearance by pressure difference |
-
2002
- 2002-11-14 GB GBGB0226529.6A patent/GB0226529D0/en not_active Ceased
-
2003
- 2003-11-12 GB GB0326358A patent/GB2395985A/en not_active Withdrawn
- 2003-11-13 US US10/712,210 patent/US20040146422A1/en not_active Abandoned
Patent Citations (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2588888A (en) * | 1949-02-08 | 1952-03-11 | Laval Steam Turbine Co | Pump |
US3247580A (en) * | 1962-05-09 | 1966-04-26 | Laval Turbine | Method of making screw pumps |
US3291061A (en) * | 1963-07-23 | 1966-12-13 | Kosaka Kenkyusho Ltd | Screw pump or hydraulic screw motor |
US3289600A (en) * | 1964-03-13 | 1966-12-06 | Joseph E Whitfield | Helically threaded rotors for screw type pumps, compressors and similar devices |
US4405286A (en) * | 1982-01-21 | 1983-09-20 | The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration | Actively suspended counter-rotating machine |
US5066205A (en) * | 1989-05-19 | 1991-11-19 | Excet Corporation | Screw rotor lobe profile for simplified screw rotor machine capacity control |
US5123821A (en) * | 1990-03-08 | 1992-06-23 | Allweiler Ag | Screw spindle pump with a reduced pulsation effect |
US5934891A (en) * | 1995-06-22 | 1999-08-10 | Kone Oy | Constant leakage flow, pulsation free screw pump |
US6139297A (en) * | 1995-12-11 | 2000-10-31 | Ateliers Busch S.A. | Double worm system |
US6158996A (en) * | 1996-09-12 | 2000-12-12 | Ateliers Busch S.A. | Screw rotor set |
US5911743A (en) * | 1997-02-28 | 1999-06-15 | Shaw; David N. | Expansion/separation compressor system |
US6019586A (en) * | 1998-01-20 | 2000-02-01 | Sunny King Machinery Co., Ltd. | Gradationally contracted screw compression equipment |
US6257854B1 (en) * | 2000-02-02 | 2001-07-10 | Industrial Technology Research Institute | Double screw rotor assembly having means to automatically adjust the clearance by pressure difference |
Also Published As
Publication number | Publication date |
---|---|
GB0326358D0 (en) | 2003-12-17 |
GB2395985A (en) | 2004-06-09 |
GB0226529D0 (en) | 2002-12-18 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US5171138A (en) | Composite stator construction for downhole drilling motors | |
KR101351667B1 (en) | Vacuum pump | |
US7452194B2 (en) | Screw pump | |
US6716008B1 (en) | Eccentric screw pump with expanded temperature range | |
US6971848B2 (en) | Multistage pump and method of making same | |
EP2610493B1 (en) | Stator seal structure for single-shaft eccentric screw pump | |
US20220205445A1 (en) | Axial Load In Helical Trochoidal Rotary Machines | |
EP0200448A2 (en) | Peristaltic pump | |
JP4779868B2 (en) | Screw pump | |
US7234925B2 (en) | Screw pump | |
JP2009074554A (en) | Multi-stage helical screw rotor | |
JP2002031071A (en) | Vacuum pump | |
US20040146422A1 (en) | Pump | |
RU2214513C1 (en) | Gyration machine | |
RU55050U1 (en) | DEVICE FOR PUMPING GAS-LIQUID MIXTURES DURING TECHNOLOGICAL OPERATIONS IN WELLS | |
EP3114350B1 (en) | Three-gear pump system for low viscosity fluids | |
US7275921B2 (en) | Pumps | |
EP1921318A1 (en) | Uniaxial eccentric screw pump | |
KR100286713B1 (en) | Gear pump | |
EP1130263A2 (en) | Helical gear vacuum pump | |
RU2667562C1 (en) | Stage of a multistage submersible centrifugal pump | |
KR200206918Y1 (en) | Oil pump with discharge flow restriction structure | |
GB2401401A (en) | Three rotor screw pump with smaller central rotor | |
US5018952A (en) | Single screw mechanism with gaterotor housing at intermediate pressure | |
KR200236543Y1 (en) | Pump |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: DANA AUTOMOTIVE LIMITED, UNITED KINGDOM Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:EDSTROM, SOREN;BLACK, DAVID THOMAS;BUTTERY, TIM;REEL/FRAME:015198/0447 Effective date: 20040224 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO PAY ISSUE FEE |