US2963981A - Variable discharge rotary pump - Google Patents
Variable discharge rotary pump Download PDFInfo
- Publication number
- US2963981A US2963981A US645107A US64510757A US2963981A US 2963981 A US2963981 A US 2963981A US 645107 A US645107 A US 645107A US 64510757 A US64510757 A US 64510757A US 2963981 A US2963981 A US 2963981A
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- United States
- Prior art keywords
- rotor
- switching cylinder
- shaft
- casing
- rotary pump
- 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.)
- Expired - Lifetime
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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
- F04C2/30—Rotary-piston machines or pumps having the characteristics covered by two or more groups F04C2/02, F04C2/08, F04C2/22, F04C2/24 or having the characteristics covered by one of these groups together with some other type of movement between co-operating members
- F04C2/36—Rotary-piston machines or pumps having the characteristics covered by two or more groups F04C2/02, F04C2/08, F04C2/22, F04C2/24 or having the characteristics covered by one of these groups together with some other type of movement between co-operating members having both the movements defined in groups F04C2/22 and F04C2/24
Definitions
- the present invention relates to the variable discharge rotary pump having a rotor with a pair of vanes of semicircular cross section projecting a diametrically opposite side of the rotor and a switching cylinder having a semicircular recess to fit the said vane, the peripheries of the rotor and the vane being arranged rotatably maintaining close contact between them, fitting the rotor and the switching cylinder ino the casing forming an annular pumping chamber between the rotor and the casing, one side of said annular chamber being in communication to the suction and the other side of the delivery, the shaft of the regulating member slidably fit in the annular chamber and the shaft of the switching cylinder being kept in engagement with each other by means of gearing and mounted on the movable bearings rotatably and slidably with said movable bearings, the packing means being provided at the forward and backward ends of the switching cylinder and the chief object of the invention is to obtain a
- the other feature of the present invention is that the semicircular vane is formed of a circular rod fit in the similar groove cut axially on the surface of the rotor, thus facilitating the manufacture with high accuracy without skilled art.
- Another feature of this invention is that the centre of the circular rod forming the vane is located somewhat inside the circular periphery of the rotor in order to minimize the clearance between the vane and the switching cylinder, thus reducing the leakage and promoting the efficiency of the pump.
- the movable bearing is fit in the casing slidably but liquid-proof, said bearing being adjustable by a lever outside the casing, and the dial is provided to indicate the amount of discharge, facilitating the regulation of the pump.
- FIG. 1 is a longitudinal section of one aspect of the invention
- Fig. 5 a longitudinal section of the packing means on one side of the switching cylinder
- Fig. 10 a partial detail showing the relation of the rotor and the vane, and Fig. 11, shows another embodiment of the invention.
- 1 is a rotor
- 2 are rotor vanes of semicircular section arranged diametrically on opposite sides of the rotor 1.
- the top lines of the vanes are in close contact with the inner periphery of the casing 3 and the rotor 1 with the vanes 2 is driven by the shaft 4.
- 5 is a switching cylinder arranged in close contact with the underside of the casing 3 and a semicircular recess 6 is formed for engaging with the vane 2.
- an annular space is formed between the rotor 1 and the inner side of the casing 3 and the space is communicated to the suction port 7 on one side and to the delivery port 8 on the other side.
- Regulating member 10 is mounted on the shaft 9 rotatably and slidably with respect to the shaft which is kept in alignment with and extends opposite to the shaft 4.
- This regulating member is provided with a sleeveshaped part 11 fitting to the annular space formed between the inner surface of the casing 3 and the periphery of the rotor 1 with the vanes 2.
- a spur wheel 13 is fixed to the boss 12 of the regulating member.
- the boss 12 is supported by a movable bearing 14 which is mounted movably along the casing by means of a handle 15 through the screw gearing consisting of a screw rod 16 and a transfer member 17 attached to the hearing.
- the shalt 18 of the switching cylinder 5 is supported by the bearing 19 fixed to the movable bearing 14 so that the bearing 19 is moved simultaneously with the movable bearing 14.
- a spur wheel 20 is fixed to the shaft 18 and kept in engagement with the spur wheel 13.
- the packing sleeve 2.5 is loosely mounted on the shaft 18 between the switching cylinder 5' and the spur wheel 20 so that the upper curved recess 24 of the packing sleeve 23 is in close contact with the outer surface of the regulating member 10. 'lhus, the spaces in both ends of the switching cylinder is closed completely.
- the sleeve-shaped part 11 of the regulating member 10 is brought into engagement with the annular space of the rotor 1 as shown in big. 1, and the packing arm 22 comes in engagement with the forward end of the recess 6 of the switching cylinder 5 and the driving shaft 4 is rotated, then the rotor 1 is driven with the regulating member 10 and the gear 13 and the switching cylinder 5 is also rotated through the engagement of the gears 13 and 20.
- Fig. 9 illustrates the pumping action of the rotor 1 and the switching cylinder 5 in which, Fig. A shows the end of the suction on one side and the beginning of the delivery on the other side, and Fig. B, Fig. C and Fig.
- the discharge of the pump may easily be regulated by means of a handle 15 outside the casing even when the pump is running. Namely, turning the handle 15, the transfer member 17 is transferred by the engagement with the screw rod 16, with the result that the bearings 14 and 19 are moved so that the sleeve-shaped part 11 of the regulating member 16 is moved into or out of the annular space between the periphery of the rotor 1 and the inner wall of the casing 3 to vary the volume of the pumping chamber.
- the recess 6 of the switching cylinder 5 may be moved freely along the packing arm 22 of the packing member 21 always maintaining close contact with the arm and the packing member rotates with the shaft 18. Accordingly, the running of the pump is not interrupted during the regulating operation.
- the vane 2 is formed of a finished circular rod fixed on'the rotor 1, fitting the rod into the semicircular groove which may be cut accurately and simultaneously with the groove on the sleeve-shaped part 11 of the regulating member.
- the difficulty of manufacturing is reduced considerably and the accuracy of the fitting is far better than similar pumps.
- the centre C of the vane 2 is selected somewhat inside of the rotor periphery as shown in Fig. 10, to effect the complete cut ofi the suction and the delivery sides.
- the result of the experiment of a rotary pump, according to this invention whose rotor diameter is 133 mm., dia. of the switching cylinder 66.5 mm., dia. of vane'43 mm., and the centre to centre distance of the rotor and the switching cylinder is as follows:
- the driving shaft 4 is extended lengthwise instead of the shaft 9 already described, on which the regulating member 10 is mounted slidably and rotatably.
- the casing 3 is closed by the cover 25 and the movable bearings 14 and 19, the gears 13 and being located outside the said movable bearings and fixed to the boss 12 of the regulating" member 10 and to the shaft 18 respectively.
- a rotary collar '26 is mounted loosely on theboss 12 and is pivoted to the yoke 27 fixed to the shaft 28.
- the regulating lever 29 is fixed to the shaft 28 and is provided with an indicator needle 30 at its free end. This lever may be controlled by a handle 31.
- a pump comprising a casing, arotor rotatable in said casing and defining an annular chamber therewith, said rotor defining a peripheral axially disposed groove, and a rod fixed in said groove and extending outwardly thereof into said annular chamber, said rod having a cross-section corresponding to the cross-section of said groove, said rod having a center adjacent but within the periphery of the rotor, the rod having less than half its periphery in engagement with the rotor.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Rotary Pumps (AREA)
Description
Dec. 1960 TADASHI HANATSUKA 2,963,981
VARIABLE DISCHARGE ROTARY PUMP 2 Sheets-Sheet 1 Filed March 11, 1957 F/EZH F/HE Dec. 13, 1960 I TADASHI HANATSUKA 2,963,981
VARIABLE DISCHARGE ROTARY PUMP Filed March 11, 1957 2 Sheets-Sheet 2 United States Patent VARIABLE DISCHARGE ROTARY PUMP Tadashi Hanatsuka, 180 Ichinosawa-cho, Utsunomiya Shi, Tochigi-ken, Japan Filed Mar. 11, 1957, Ser. No. 645,107
1 Claim. (Cl. 103125) The present invention relates to the variable discharge rotary pump having a rotor with a pair of vanes of semicircular cross section projecting a diametrically opposite side of the rotor and a switching cylinder having a semicircular recess to fit the said vane, the peripheries of the rotor and the vane being arranged rotatably maintaining close contact between them, fitting the rotor and the switching cylinder ino the casing forming an annular pumping chamber between the rotor and the casing, one side of said annular chamber being in communication to the suction and the other side of the delivery, the shaft of the regulating member slidably fit in the annular chamber and the shaft of the switching cylinder being kept in engagement with each other by means of gearing and mounted on the movable bearings rotatably and slidably with said movable bearings, the packing means being provided at the forward and backward ends of the switching cylinder and the chief object of the invention is to obtain a rotary pump of high efiiciency and compact design at comparatively low cost.
The other feature of the present invention is that the semicircular vane is formed of a circular rod fit in the similar groove cut axially on the surface of the rotor, thus facilitating the manufacture with high accuracy without skilled art.
Another feature of this invention is that the centre of the circular rod forming the vane is located somewhat inside the circular periphery of the rotor in order to minimize the clearance between the vane and the switching cylinder, thus reducing the leakage and promoting the efficiency of the pump.
Another feature of this invention is that the movable bearing is fit in the casing slidably but liquid-proof, said bearing being adjustable by a lever outside the casing, and the dial is provided to indicate the amount of discharge, facilitating the regulation of the pump.
The annexed drawings show several embodiments of the invention, in which Fig. 1 is a longitudinal section of one aspect of the invention,
Fig. 2, cross section on the line II-II of Fig. 1,
Fig. 3, a longitudinal section of the regulating means, Fig. 4, the end view of the same,
Fig. 5, a longitudinal section of the packing means on one side of the switching cylinder,
Fig. 6, the end view of the same,
Fig. 7, the side view of the packing means on the other side of the switching cylinder,
Fig. 8, the end view of the same,
Fig. 9, the skeleton drawing illustrating the operation of the pump,
Fig. 10, a partial detail showing the relation of the rotor and the vane, and Fig. 11, shows another embodiment of the invention.
Referring to the drawings, 1 is a rotor, 2 are rotor vanes of semicircular section arranged diametrically on opposite sides of the rotor 1. The top lines of the vanes are in close contact with the inner periphery of the casing 3 and the rotor 1 with the vanes 2 is driven by the shaft 4. 5 is a switching cylinder arranged in close contact with the underside of the casing 3 and a semicircular recess 6 is formed for engaging with the vane 2. Thus, an annular space is formed between the rotor 1 and the inner side of the casing 3 and the space is communicated to the suction port 7 on one side and to the delivery port 8 on the other side.
Regulating member 10 is mounted on the shaft 9 rotatably and slidably with respect to the shaft which is kept in alignment with and extends opposite to the shaft 4. This regulating member is provided with a sleeveshaped part 11 fitting to the annular space formed between the inner surface of the casing 3 and the periphery of the rotor 1 with the vanes 2. A spur wheel 13 is fixed to the boss 12 of the regulating member. The boss 12 is supported by a movable bearing 14 which is mounted movably along the casing by means of a handle 15 through the screw gearing consisting of a screw rod 16 and a transfer member 17 attached to the hearing.
The shalt 18 of the switching cylinder 5 is supported by the bearing 19 fixed to the movable bearing 14 so that the bearing 19 is moved simultaneously with the movable bearing 14. On the shaft 18, near its front end a packing member 21 is fixed, whose packing arm 22 is clcsely engaged with the recess 6 of the switching cylinder 5. A spur wheel 20 is fixed to the shaft 18 and kept in engagement with the spur wheel 13. The packing sleeve 2.5 is loosely mounted on the shaft 18 between the switching cylinder 5' and the spur wheel 20 so that the upper curved recess 24 of the packing sleeve 23 is in close contact with the outer surface of the regulating member 10. 'lhus, the spaces in both ends of the switching cylinder is closed completely.
According to the present invention, the sleeve-shaped part 11 of the regulating member 10 is brought into engagement with the annular space of the rotor 1 as shown in big. 1, and the packing arm 22 comes in engagement with the forward end of the recess 6 of the switching cylinder 5 and the driving shaft 4 is rotated, then the rotor 1 is driven with the regulating member 10 and the gear 13 and the switching cylinder 5 is also rotated through the engagement of the gears 13 and 20. Fig. 9 illustrates the pumping action of the rotor 1 and the switching cylinder 5 in which, Fig. A shows the end of the suction on one side and the beginning of the delivery on the other side, and Fig. B, Fig. C and Fig. D show the position of the rotor rotated 20, 45 and respectively from the position shown in Fig. A. Thus, in each case, the back surface with respect to the direction of rotation of the vanes 2 serves to draw the liquid in and the forward surface to deliver it out of the annular chamber and the switching cylinder 5 comes always in contact with the rotor 1 to cut off the suction and delivery side and the continuous pumping action is eflfected during the rotation of the rotor.
The discharge of the pump, according to the present invention, may easily be regulated by means of a handle 15 outside the casing even when the pump is running. Namely, turning the handle 15, the transfer member 17 is transferred by the engagement with the screw rod 16, with the result that the bearings 14 and 19 are moved so that the sleeve-shaped part 11 of the regulating member 16 is moved into or out of the annular space between the periphery of the rotor 1 and the inner wall of the casing 3 to vary the volume of the pumping chamber.
In this case, the recess 6 of the switching cylinder 5 may be moved freely along the packing arm 22 of the packing member 21 always maintaining close contact with the arm and the packing member rotates with the shaft 18. Accordingly, the running of the pump is not interrupted during the regulating operation.
According to this invention, the vane 2 is formed of a finished circular rod fixed on'the rotor 1, fitting the rod into the semicircular groove which may be cut accurately and simultaneously with the groove on the sleeve-shaped part 11 of the regulating member. Thus, the difficulty of manufacturing is reduced considerably and the accuracy of the fitting is far better than similar pumps.
The centre C of the vane 2 is selected somewhat inside of the rotor periphery as shown in Fig. 10, to effect the complete cut ofi the suction and the delivery sides. The
contact line of the vane 2 and the switching cylinder 5 is always kept in contact forming little clearance between them notwithstanding the contact line changes from time to time, and the suction side is completely shut out of the delivery side of the pump throughout the revolution.
For example, the result of the experiment of a rotary pump, according to this invention, whose rotor diameter is 133 mm., dia. of the switching cylinder 66.5 mm., dia. of vane'43 mm., and the centre to centre distance of the rotor and the switching cylinder is as follows:
In a modified embodiment shown in Fig. 11, the driving shaft 4 is extended lengthwise instead of the shaft 9 already described, on which the regulating member 10 is mounted slidably and rotatably. The casing 3 is closed by the cover 25 and the movable bearings 14 and 19, the gears 13 and being located outside the said movable bearings and fixed to the boss 12 of the regulating" member 10 and to the shaft 18 respectively. A rotary collar '26 is mounted loosely on theboss 12 and is pivoted to the yoke 27 fixed to the shaft 28. The regulating lever 29 is fixed to the shaft 28 and is provided with an indicator needle 30 at its free end. This lever may be controlled by a handle 31.
When the handle 31 is rotated; the lever 29 swings up or down, thereby causing the regulating member 10 to slide from or into the annular pumping chamber by means of the yoke 27 and the collar 26, varying the discharge of the pump as described; The amount of discharge is indicated by the indicator needle 30 and the graduation 32.
I claim:
A pump comprising a casing, arotor rotatable in said casing and defining an annular chamber therewith, said rotor defining a peripheral axially disposed groove, and a rod fixed in said groove and extending outwardly thereof into said annular chamber, said rod having a cross-section corresponding to the cross-section of said groove, said rod having a center adjacent but within the periphery of the rotor, the rod having less than half its periphery in engagement with the rotor.
References Cited in the file of this patent UNITED STATES PATENTS 137,055 Chapman Mar. 25, 1873 137,058 Chapman Mar. 25, 1873 214,699 Phinney et al. ....a Apr. 22, 1879 788,848 Riegel May 2, 1905 1,276,372 Johnson Aug. 20, 1918 1,944,018 Thompson Jan. 16, 1934 2,258,504 Booth Oct. 7, 1 941 2,442,130 Johnson May 25, 1948 2,483,705 Levetus et al. Oct. 4, 1949 2,728,299 Johnson Dec. 27, 1955 2,776,086 Selden Jan. 1, 1957 FOREIGN PATENTS 448,952 Great Britain June 18, 1936 665,963 Germany Oct. 6, 1938
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US645107A US2963981A (en) | 1957-03-11 | 1957-03-11 | Variable discharge rotary pump |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US645107A US2963981A (en) | 1957-03-11 | 1957-03-11 | Variable discharge rotary pump |
Publications (1)
Publication Number | Publication Date |
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US2963981A true US2963981A (en) | 1960-12-13 |
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ID=24587663
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US645107A Expired - Lifetime US2963981A (en) | 1957-03-11 | 1957-03-11 | Variable discharge rotary pump |
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US (1) | US2963981A (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3417915A (en) * | 1966-10-10 | 1968-12-24 | Albert J. Granberg | Rotary blower and timing adjustment mechanism |
US3584984A (en) * | 1968-02-03 | 1971-06-15 | Zaklady Mechanizzne Tarrow | Rotary device |
US3592569A (en) * | 1969-08-22 | 1971-07-13 | Doyle V Rowland | Variable displacement fluid device |
US4872536A (en) * | 1986-09-24 | 1989-10-10 | Zheng Yue | Hydraulic pumps or motors and hydrostatic transmitting systems |
US5246358A (en) * | 1992-01-16 | 1993-09-21 | Inhoy Gu | Cam-gear pump-compressor apparatus |
Citations (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US137058A (en) * | 1873-03-25 | Improvement in rotary pumps | ||
US137055A (en) * | 1873-03-25 | Improvement in rotary pumps | ||
US214699A (en) * | 1879-04-22 | Improvement in rotary pump and blower | ||
US788848A (en) * | 1904-09-21 | 1905-05-02 | John Clinton Riegel | Variable-speed hydraulic-power-transmission mechanism. |
US1276372A (en) * | 1916-06-21 | 1918-08-20 | Walter C Shultz | Rotary pump. |
US1944018A (en) * | 1931-06-29 | 1934-01-16 | Harry A Thompson | Fluid operated gearing |
GB448952A (en) * | 1935-02-04 | 1936-06-18 | Francis Benjamin Levetus | Improvements in or relating to rotary pumps and the like |
DE665963C (en) * | 1933-10-06 | 1938-10-06 | Gerhard Schimkat | Rotary lobe pump with rod-shaped delivery pistons and a control piston rotating in an annular space |
US2258504A (en) * | 1937-06-04 | 1941-10-07 | Keelavite Co Ltd | Rotary fluid pressure engine and the like |
US2442130A (en) * | 1943-06-10 | 1948-05-25 | Keelavite Co Ltd | Rotary fluid pressure motor, pump, and the like |
US2483705A (en) * | 1941-09-16 | 1949-10-04 | Keelavite Co Ltd | Rotary engine, pump, and the like |
US2728299A (en) * | 1951-11-21 | 1955-12-27 | Keelavite Co Ltd | Variable capacity rotary hydraulic pump or motor |
US2776086A (en) * | 1952-03-18 | 1957-01-01 | Irving H Selden | Fluid compressor or pump |
-
1957
- 1957-03-11 US US645107A patent/US2963981A/en not_active Expired - Lifetime
Patent Citations (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US137055A (en) * | 1873-03-25 | Improvement in rotary pumps | ||
US214699A (en) * | 1879-04-22 | Improvement in rotary pump and blower | ||
US137058A (en) * | 1873-03-25 | Improvement in rotary pumps | ||
US788848A (en) * | 1904-09-21 | 1905-05-02 | John Clinton Riegel | Variable-speed hydraulic-power-transmission mechanism. |
US1276372A (en) * | 1916-06-21 | 1918-08-20 | Walter C Shultz | Rotary pump. |
US1944018A (en) * | 1931-06-29 | 1934-01-16 | Harry A Thompson | Fluid operated gearing |
DE665963C (en) * | 1933-10-06 | 1938-10-06 | Gerhard Schimkat | Rotary lobe pump with rod-shaped delivery pistons and a control piston rotating in an annular space |
GB448952A (en) * | 1935-02-04 | 1936-06-18 | Francis Benjamin Levetus | Improvements in or relating to rotary pumps and the like |
US2258504A (en) * | 1937-06-04 | 1941-10-07 | Keelavite Co Ltd | Rotary fluid pressure engine and the like |
US2483705A (en) * | 1941-09-16 | 1949-10-04 | Keelavite Co Ltd | Rotary engine, pump, and the like |
US2442130A (en) * | 1943-06-10 | 1948-05-25 | Keelavite Co Ltd | Rotary fluid pressure motor, pump, and the like |
US2728299A (en) * | 1951-11-21 | 1955-12-27 | Keelavite Co Ltd | Variable capacity rotary hydraulic pump or motor |
US2776086A (en) * | 1952-03-18 | 1957-01-01 | Irving H Selden | Fluid compressor or pump |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3417915A (en) * | 1966-10-10 | 1968-12-24 | Albert J. Granberg | Rotary blower and timing adjustment mechanism |
US3584984A (en) * | 1968-02-03 | 1971-06-15 | Zaklady Mechanizzne Tarrow | Rotary device |
US3592569A (en) * | 1969-08-22 | 1971-07-13 | Doyle V Rowland | Variable displacement fluid device |
US4872536A (en) * | 1986-09-24 | 1989-10-10 | Zheng Yue | Hydraulic pumps or motors and hydrostatic transmitting systems |
US5246358A (en) * | 1992-01-16 | 1993-09-21 | Inhoy Gu | Cam-gear pump-compressor apparatus |
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