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Publication numberUS1572738 A
Publication typeGrant
Publication dateFeb 9, 1926
Filing dateOct 27, 1924
Priority dateOct 27, 1924
Publication numberUS 1572738 A, US 1572738A, US-A-1572738, US1572738 A, US1572738A
InventorsSamuel Maroger
Original AssigneeSamuel Maroger
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Rotary pump for liquids or gases
US 1572738 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

Feb. 9 1926. y




Application filed October 27, 1924. Serial No. 746,106.

To all 'whom it lmay concern:

Be it known that I, SAMUEL MAnoonk, a citizen of the Republic ot' France, residing at 2G Rue Dhuoda, Nimes, Gard, France, have inventnd new and useful Improvements in Rotary Pumps l'or Liquids or Gases, of which the following is a specilication.

Rotary pumps, of the screw type usually comprise a screw rotating in a cylinder and a special device (star or toot-hed wheel) which prevents the liquid which iills the pump from taking part in the rotary movement of the screw, so that the liquid moves in accordance with the generatrices ot' the cylinder which forms the body ot' the pump and it remains constantly imprisoned between the threads of the screw.

Such an arrangement is subject to the drawback that it complicates the internal mechanism of the apparatus owing to the fact that special means must be provided tol prevent the liquid from participating in the movement ot the screw.

This invention relates to a pump of the type referred to which does not comprise any special means for the purpose mentioned, apart from the body of the pump itself and the screw, the screw being arranged in such a manner that the helicoidal entrainment ot' the iuid (liquid or gas) cannot take place. The device presents the further advantages, owing to the uses to which it can be put, of enabling large outputs to be obtained as well as of being capable ot' running at approximately the same speeds as the motor to which the pump is coupled, the same arrangement being applicable for the purpose of obtaining high vacua or pressures.

The invention consists in mounting, in the body ot the pump, a drum ot' smaller diameter which constitutes the body of the driving screw and in placing this drum eccentrically relative to the pump body in such a manner that they are tangential to each other, the said drum having a helicoidal groove in which is fitted a helix ot corresponding pitch, but of the same diameter as the pump body, the helix being fitted in its groove with a certain amount of clearance in order to enable it to move therein and to take up easily any wear which may arise.

In order to avoid leakage and to ensure tightness of the pump, it is necessary that the thread ot the helix shall make a number of revolutions or fractions ot revolutions such that the same thread touches the pumpbody at least twice. In the case of a pump having a single thread, two revolutions are therefore necessary and the pump-body 'must be made sufficiently long. It, however, two threads are provided, one and one half revolutions will be suilicient to ensure tightness, and by this means the length of the pump body necessary for a given output can be diminished.

The invention contemplates the formation of the body of the screw of a series of discs, placed side by side, and mounted upon the same shaft, which is eccentric to the pumpbody, these discs having straight grooves of suitable inclination and corresponding to that of the thread of the screw which it is' desired to obtain, and also the mounting of straight blades in these grooves in such a manner that they can move therein independently of each other, the entire device, while presenting the general aspect of a screw and oii'ering the advantage that its manufacture and erection are simple, while its operation is consistent.

In the drawing, Fig. 1 is a transverse seetion of a rotary pump constructed according to the present invention. l

Figs. 2 and 8 are detail views showing, respectively, one of the discs shown in Fig. 1 and one of the blades intended to be mounted in this disc.

In the examples shown in Figs. 1 to 3, the pump-body 1 is provided at its extremities with admission and discharge nozzles 2 and 3 and has bearings 4 for the reception of the shaft of the rotary member of the pump, these bearings being formed eccentrically relative to the pump-body 1. The rotary member comprises a series of disks l0 of smaller diameter than the interior of the body of `he pump and placed side by side on the shaft 6 and, owing to the eccentrieity of the shaft 6, which can rotate in the bearings 4, the disks l0 are tangent to the bore of the body of the pump only along one of their generatriees. A thrust-bearing is formed at one of the extremities of the shaft 6, while the other extremity rotates in a stuffing box 7 which ensures a fluid ti ht fit Upon the discs 10 there are ormed obliquely straight grooves 12, the sequence of which represents substantially the aspect of a helicoidal groove formed of broken lines; and, iu the ease of two threads, these grooves will be disposed inversely relative to the two extremities of a diameter of each of the `ment of the helix.

discs, in such a manner that each of the extremities of' thegrooves of one of them coincides with the extremity of a groove of the adjacent disc. The blades 11 can be mounted in the grooves 12 and can move in the latter, the face 13 of each'of said blades being formed in such a manner that it can bear exactly upon the bore of the body of the pump. The blades are constantly pressed against the bore of the body of the; pump by centrifugal force, so that any wear is automatically compensated. The shaft 6 of the drum, being driven by the motor, the disks 10 comprising the rotary member and the blades 11 carried thereby are caused to rotate. The fluid (gas or liquid) which fills the pump, cannot take part in the rotary movement of the helix formed by the blades 1l since there is no room for the passage of such fluid at the line of tangency between the disks 10 and the body '1 of' the pump, so that it can only follow the advancing move- The result is that the fluid taken in at the admission nozzle 2 is forced out through the discharge vnozzle 3.

It is evident that certain modifications could be made in this arrangement of rotary pump or that other systems of mounting the screw could be devised without departing from the spirit of the invention.

I claim:

1. A rotary pump comprising in combination a pump-body, a drum mounted eccentrically in said pump-body, said drum having a helical groove, and a helix fitted in said groove, said helix being made in sections for the purpose set forth.

2. A rotary pump comprising in combination a pump-body, a drum mounted eccentrically in said body so as to contact therewith along one generatrix alone, said drum having a plurality of helicoidal grooves, and a helix formed in sections fitted in each of said grooves.

3. A rotary pump comprising in combination a pump-body, a plurality ofi' discs mounted eccentrically in said body and contacting therewith along a generati-ix, said discs having grooves, and blades fitted in said grooves and adapted to contact with the inner wall of said pump body.

4. A rotary pump comprising in combination a pump-body, a plurality of discs mounted eccentrically in said body and contacting therewith along a generatrix, said discs having straight grooves arranged obliquely, and blades fitted in said grooves and contacting with the inner Wall of said pump body.

5. A rotary pump comprising in combination a pump-body, a shaft mounted eccentrically in said pump-body, a plurality of discs mounted concentrically upon said shaft and of such diameter as to contact with said pump-body along one generatrix only, said discs having straight grooves'arranged in such relativeformation as to form substantially a helicoidal line, and blades fitted in said grooves.


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2527536 *May 15, 1945Oct 31, 1950Engberg Ralph ERotary screw pump
US3609071 *Dec 10, 1969Sep 28, 1971United Hydraulics IncVanes for fluid power converter
US4561837 *May 15, 1980Dec 31, 1985Leybold-HeraeusMethod of producing a rotor for rotary slide-vane vacuum pumps, and a rotor produced by said method
US4997352 *Jan 24, 1990Mar 5, 1991Kabushiki Kaisha ToshibaRotary fluid compressor having a spiral blade with an enlarging section
EP0381061A2 *Jan 25, 1990Aug 8, 1990Kabushiki Kaisha ToshibaFluid compressor
U.S. Classification418/270
International ClassificationF04D3/00
Cooperative ClassificationF04D3/00
European ClassificationF04D3/00