US3575540A

US3575540A - Airtight equipment in a rotary pump

Info

Publication number: US3575540A
Application number: US824788A
Authority: US
Inventors: Kazuo Satake
Original assignee: Individual
Current assignee: Individual
Priority date: 1969-05-15
Filing date: 1969-05-15
Publication date: 1971-04-20
Anticipated expiration: 1988-04-20

Abstract

Means for improving the fluid tightness of a rotary pump. A bisected annular plate is provided between each end of the rotor and the casing through which the drive shaft extends, one-half of the plate being on the intake side of the casing and the other half being on the discharge side of the casing. The half of the plate on the intake side is drawn toward the rotor by the reduced pressure at the intake side, while the half of the plate on the discharge side is urged away from the rotor by the pressure.

Description

United States Patent Kazuo Satake No. 77, 2-cho,0htari Minami-Machi, Sakai-shi, Japan May 15, 1969 Apr. 20, 1971 lnventor Appl. No. Filed Patented AIRTIGHT EQUIPMENT IN A ROTARY PUMP 3 Claims, 3 Drawing Figs.

US. Cl 418/133 Int. Cl F010 19/08, F040 27/00 Field 01' Search 103/216, 144, 126,120, 1323;230/152;91/14l;418/103; 418/131-135 References Cited UNITED STATES PATENTS Wilsey l03/l26(S)UX 1,996,875 4/1935 McCann 91/141X 3,184,156 5/1965 Welch et al.... 230/152 3,187,993 6/1965 Rhodes 230/152 3,303,793 2/1967 Morita 103/126(S)UX 3,327,638 6/1967 Scognamillo 103/136 3,479,962 11/ 1969 Pettibone 103/ 136 Primary Examiner-Carlton R. Croyle Assistant Examiner-John .I Vrablik Attorney-Wenderoth, Lind & Ponack ABSTRACT: Means for improving the fluid tightness of a rotary pump. A bisected annular plate is provided between each end of the rotor and the casing through which the drive shaft extends, one-half of the plate being on the intake side of the casing and the other half being on the discharge side of the casing. The half of the plate on the intake side is drawn toward the rotor by the reduced pressure at the intake side, while the half of the plate on the discharge side is urged away from the rotor by the pressure.

PATENIEMm Ian SHEET 1 UF 3 N m a g at INVENT OR Kazuo Satake ATTORNEY PATENTEU APR 20 I97! SHEET 2 0F 3 m, q z.

INVENTOR Kazuo Satake avwxfi) 3M ATTORNEY PATENTED APRZO IHTI SHEET 3 or 3 INVENT OR Kazuo-Satake BYLJMQLSQQW ATTORNEY tllllt'llfirfll'f' EOTJWMENT IN A ROTARY PUMP This invention relates to equipment with which to improve the airtightness between the terminal surface of a rotor and the casing of a rotary pump.

In relation to improvement of the efficiency of a rotary pump the idea which is readily conceivable is to interpose an airtight plate between the rotor and the casing. However, from mere interposition of a single disc-shaped airtight plate between the rotor end and the pump casing no satisfactory airtight effect is obtainable, even when the said airtight plate is pressed to the rotor end with relatively great force.

This is due to the fact that a backward pressure generated on the side of the discharge outlet at the time of the operation of the pump is propagated to the airtight plate inside the casing, giving the said plate an outwardly curved distortion, with the result that a gap arising between the airtight plate and the rotor end deprives the said airtight plate of its satisfactory function.

The object of the invention is to remarkably enhance the efficiency of the pump by eliminating the aforementioned defect and bringing the airtight plate into closer contact with the terminal surface of the rotor during the operation of the pump, so that the airtight function will be maintained as near to perfection as possible.

The foregoing object is attainable by improving the airtight plate, and a preferred embodiment thereof will be illustrated in detail by the description set forth hereinunder and the drawings annexed hereto.

Modifications and changes with regard to the particulars of the construction are to be included in the claims which will appear hereinafter.

1n the drawings:

FlG. l is a longitudinally sectional elevation of a rotary pump provided with the airtight equipment of the invention.

FIG. 2 is a lateral view of a longitudinal section of the rotary pump of HG. ll.

FIG. 3 is a perspective view of a part of the said rotary pump disassembled.

1n the airtight equipment according to the invention the airtight plate to be interposed between the rotor end and the casing is divided into two sections, one for the side of the discharge area and the other for the side of the suction area.

in F105. l to 3 the numeral ll indicates the airtight plates of the invention, two semicircular plates forming a single disc when titted to each other at the straight rims 12 thereof which correspond to the chords of the semicircles.

On the part of the straight rim 12 of each airtight plate is eccentrically formed a semicircular hollow R3, the said hollows 13 when the two airtight plates 111 are fitted together at the respective straight rims 12 thereof constituting a hole through which a rotary shaft penetrates.

Each of the airtight plates 11 is provided with a pair of rotation arresting pins M respectively, which serve to arrest the rotation of the airtight plates 11 by fitting into a plurality of holes 15 formed in the internal surface of each casing cover E5.

The numeral 117 designates a pump casing, on the external periphery thereof a discharge outlet 30 and a suction inlet 31 being provided respectively. On both sides of the casing 17 are fastened the aforementioned covers 15 with bolts, inside the casing 17 being fixed a cylindrical liner 18 having

holes

32, 33 which communicate with the discharge outlet 30 and the suction inlet 51;, sealed packings 19 being interposed between the casing t7 and the cover 15.

The numeral 2% indicates a rotor shaft, which is revolvably fixed to the right and the left covers 15 through bearings 21. The said rotor shaft 2b is fixed in parallel with the cylindrical liner lb inside the casing 17 and in an upwardly eccentric state, the rotor body 22'being fixed concentrically with the rotor shaft 20 at the area where the rotor shaft 241 is located inside the casing l7. Since the rotor body 22 is eccentric against the liner 1%, it is so arrangedthat the rotor body 22 may be freely revolvable inside the liner 118 by making the diameter of the rotor body 22 considerably smaller than the bore of the liner lib.

On the said rotor body 22 a plurality of, say six, deep grooves 23 are formed at regular intervals running from the external periphery toward the center thereof. In each of the said grooves 23 is slidably fitted a vane 24.

There exists some space between both terminal rims of the foregoing vane 24 and the right and the left covers 15 respectively, the aforementioned airtight plates 11 being inserted into the'said space, the rotor shaft 20 penetrating through the hollows 13 of the respective airtight plates 11.

[t is so arranged that both ends of the rotor body 22 be positioned further inside of both terminal rims of each vane 24, the external periphery of a mouth ring 25 which is loosely fitted to the rotor shaft 20 on the outside at both ends of the rotor body 22 being in contact with the inside surface of both ends of the vane 24 respectively, the external rim of the vane 24 being constantly slidable on the internal surface of the liner 1%.

One end of the rotor shaft 20 protrudes outwardly through the central hole of alid 26 which is fastened with bolts to the outside of one of the covers 15, a V-pulley 27 being fixed to the end thereof, the other end of the rotor shaft 20 terminating at the external end of the cover 15 on that side and being covered by a lid 28 which is fastened with bolts to the outside of the cover 15. Oil seals 29 are fitted to the parts where the rotor shaft runs through each cover 15.

Alternatively both ends of the rotor body may be brought in contact with the airtight plates 11 by omitting the mouth ring 25.

The foregoing rotor body 22, the mouth ring 25 and the vanes 24 are given the general name of rotor.

In the rotary pump equipped with an airtight plate 11 which is divided into two sections as described above, if the rotor shaft 21] is revolved by driving the V-pulley 27 by means of an appropriate motor, water or the like fluid sucked through the suction inlet 31 is discharged toward the. discharge outlet 30 by the rotor in the same way as in the case of the ordinary rotary pump.

When the fluid runs as described above, the semicircular airtight plate 11 which faces the rotary chamber located on the side of the discharge outlet from the center where the straight rims 12 of the right and the left airtight plates 11 meet as shown in FIG. 1, that is, which faces the side of the discharge area, is pressed outwardly under the discharging pressure of the fluid, the other semicircular airtight plate 11 which is so provided as to face the suction area on the side of the suction inlet 31 is sucked toward the rotor by the suction inside the rotary chamber on that side.

in the illustrated mechanism, therefore, the airtight plate 11 for the side of the suction area is tightly fitted to the mouth ring 25 and the terminal rims of the vanes 24. Also in the system wherein the mouth ring 25 is omitted, the airtight plate 11 is closely fitted to the rotor body 22 and the terminal rims of the vanes 24. Airtightness being thus maintained, the fluid suction of the suction part is remarkably increased.

In this invention, as described heretofore, it is so arranged that the airtight plate for the side of the discharge area may not affect the airtight plate for the side of the suction area by providing an airtight plate which is divided into two sections, one for the discharge area and other for the suction area respectively. As a result, the airtight plate 11 for the side of the suction area is closely fitted to the rotor without being affected by the pressure on the side of the discharge area, the suction of the rotor being thus remarkably increased. This invention therefore has an advantage in that the efficiency of the pump can be greatly enhanced.

The airtight plate 11, though its revolution together with the rotor is prevented by the rotation arresting pins 14 which are fitted into the fitting holes 16 in the casing covers 15, is freely movable in the axial direction of the rotary shaft, as a result of which the airtight plate fl and the rotor remain in close contact with each other, even when the friction surface of the airtight plate llll and that of the rotor are worn, thus preventing the efficiency of the pump from decreasing.

Furthermore, the airtight plate 11 for the side of the discharge area is of the identical shape as that for the side of the suction area. Therefore, even when the discharge outlet and the suction inlet are reversed, i.e. when the pump is of the reversible type, the airtight plate 11 which happens to be on the side of the suction area comes in close contact with the rotor, maintaining satisfactory suction, with the result that the efficiency of the pump is never impaired by reversing the pumping direction.

Moreover, the airtight plate ll for the side of the discharge area is pressed to the internal surface of the casing cover 15 by the discharging pressure, but neither the casing cover 15 nor the airtight plate 11 pressed thereto is worn out because they are stationary. Therefore, if the airtight plate 11 for the side of the suction area is worn, it can be replaced with the airtight plate 11 for the side of the discharge area, as a result of which a high pumping efficiency is maintainable without the trouble of changing the said worn airtight plate 11 for a new one.

ln the embodiment illustrated, the airtight plate 11 for the side of the discharge area and that for the side of the suction area are separated from each other with the rotary shaft between them, but both plates 11 can be movably connected together with connecting pieces of appropriate flexibility. Besides, it is desirable that both sides of each revolvable vane 24 should be prevented from scratching the straight rims 12 of the airtight plate 11 by giving appropriate roundness to both sides of the said straight rims.

lclaim:

1. In a rotary pump including a casing having a pair of casing covers, a rotor shaft mounted in said covers and extending through the interior of said casing, and a rotor mounted on said shaft within said interior of said casing, said casing having a suction inlet and a discharge outlet extending into and from'said interior, whereby said interior includes a suction area and a discharge area and the path of pumping of said rotor pump is transverse to the axis of said shaft from said suction inlet, into said suction area, then into said discharge area and out said discharge outlet; the improvement comprising a pair of discs surrounding said shaft and positioned between the terminal edges of said rotor and said covers, each of said discs comprising a pair of semicircular plates, the first of said plates of each of said discs being positioned in said suction area, and the second of said plates of each of said discs being positioned in said discharge area.

2. In a rotary pump as claimed in claim 1, wherein said covers have holes therein, and said plates have arresting pins positioned in said holes, thereby preventing rotation of said plates when said shaft rotates.

3. ln a rotary pump as claimed in claim 1, wherein said pair of plates of each of said discs are connected by flexible connecting pieces.

Claims

1. In a rotary pump including a casing having a pair of casing covers, a rotor shaft mounted in said covers and extending through the interior of said casing, and a rotor mounted on said shaft within said interior of said casing, said casing having a suction inlet and a discharge outlet extending into and from said interior, whereby said interior includes a suction area and a discharge area and the path of pumping of said rotor pump is transverse to the axis of said shaft from said suction inlet, into said suction area, then into said discharge area and out said discharge outlet; the improvement comprising a pair of discs surrounding said shaft and positioned between the terminal edges of said rotor and said covers, each of said discs comprising a pair of semicircular plates, the first of said plates of each of said discs being positioned in said suction areA, and the second of said plates of each of said discs being positioned in said discharge area.

3. In a rotary pump as claimed in claim 1, wherein said pair of plates of each of said discs are connected by flexible connecting pieces.