US1531607A - High-pressure rotary pump - Google Patents

Description

March 31, 1925. 1,531,607

' T. W. GREEN HIGH PRESSURE ROTARY PUMP Fild Jan. 24, 1925 a Sheets-Sheet 1 .March 31. 1925. 1,531,607

T. W. GREEN HIGH PRESSURE ROTARY PUMP Filed Jan. 24, 1923 5 Sheets-Sheet 2 25 I F 4 i fl o o .25 O W .O i?

March 31.1925. 1,531,607

T. W. GREEN HIGH PRESSURE ROTARY PUMP Filed Jan. 24, 192:5 3 Shets-Sheet :5

Patented Mar. 31 1925.

UNITED STATES THOMAS w. GREEN, 01E PHILADELPHIA, PENNSYLVANIA.

HIGH-PRESSURE ROTARY PUMP.-

Application filed January 24, 1923. Serial No. 614,507.

To all whom it may concern:

Be it known that I, THOMAS WV. GREEN, a citizen of the United States, residing at Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented a certain new and useful High-Pressure Rotary Pump, of whichv the following is a specification.

My invention relates to multiple stage rotary pumps adapted for use in pumping or compressing fluids and semi-fluids. To indicate the range which it will handle I mention ether, gas, air, water, molasses, oil, grease, paint and tar.

The purpose of my invention is to provide a rotary pump of the character indicated which is at once adapted to meet adeguately the needs of service and to easy an inexpensive manufacture.

A further purpose is to make an improved rotary multi-stage pump upon a single pair of shafts, the individual stages comprising cooperating encased pairs of impellers of the Root type, all upon the same pair of shafts.

A further purpose is to provide a novel form of pump casing and new means for temperature regulation between stages.

Further purposes will appear in the speciiication and in the claims.

I have preferred to illustrate my invention by but one form, selecting a form that is simple and easily accessible, and efficient in operation and which well illustrates the principles involved.

Figures 1, 2 and 3 are respectively a plan view and side and end elevations of the preferred form of my invention. 4 Figure 4 is a sectional end elevation take upon line 4-4 of Figure 5.

Figure 5 is a sectional side elevation taken upon line 55 of Figure 4.

Figures 6 and 7 are respectively front and end elevations of the central supporting member.

Figure 8 is a section upon the line 88 of Figure 6.

Figure 9 is an end elevation of a detail.

Figure 10 is a section on the line 10-10 of Figure 9.

Like numerals refer to like parts in all the drawings.

Describing in illustration and not in l1m1- tation and referring to the drawings Prior to my resent invention, patents have been grants upon single stage pumps vented by me and shown in United States I 'at ent N o. 1,046,77 3.

It is frequently desirable to pump a ainst pressures greater than are readily o tainable by these single stage pumps, and also desirable to progressively regulate the temperature during passage through the pump.

Thus, when used to furnish a supply of compressed air or other gas, the requisite power consumption for compression is materially reduced by progressive cooling during compression; and again when used to pump viscous fluids such as molasses and tar it is desirable to heat the fluid to make it flow more easil and also to have the im eller blades at a iigher temperature than t at of the fluid in order to reduce the extent to which the viscous fluid sticks to the blades.

In the form illustrated, a series of pairs of impellers, 15, 16, 16', 17, 17 and 18, 18, encased to form a series of individual single stage pumps, are mounted upon and spaced along the parallel shafts 19 and 19.

Spaces are provided between the casings or enclosures 20, 21, 22 and 23 Within which the impellers of successive single stage pumps operate. The end walls (transverse to the impeller shafts) of adjoining casings or enclosures form the end walls of these spaces.

These spaces provide for conduit connection between the successive pumps from the inlet 24 of the first pump to the outlet 25 of the last.

Each of the spaces is split up into central and end compartments. The central compartments 26, 27, 28 respectively lie between vertical planes through the shafts and through these central compartments the fluid is pumped. The side or end compartments 29, '30 are shut oil from the central compartments by partition walls 31, 32 so that each compartment :29, between its partition walls and the outside walls 33 may be complete in itself to receive heating or cooling fluid for the regulation of the temperature of the fluid passing through the successive stages of the pump.

This heating or cooling fluid affects the fluid pumped not only during the time the latter is passing through the spaces but 4 while it is being pumped from one space 47 of a casing to another.

In order that impellers and casin and shafts may be very easily accessible or-inspection, removal or replacement, I provide for separation along the axes of the shafts, thus separating the stationary part. of the apparatus into a middleortion 34 between the shafts and removab e semi-cylindrical portions 35 and 36 upon either side of the middle portion.

The outer portions 35 and 36, made removable to provide easy accessibility to any part of the interior, may com rise integral castings each, extendin the ength of the ump structure, but pre erabl are made up in sections, 37, 38, 39 40 an 41 as shown in the form illustrated. Each of the intermediate sections of the outer portions (Fig. 10 includes an inwardly-facing semi-cylindrical shell to complete the operating chamher for one of the impellers and an intermediate fluid compartment for temperature regulation. The end section 37 acts as a shell only for the impeller chamber and the section 41 carries a heating or cooling chamber.

The middle member 34 may also be made either integral or in sections. Usually I prefer to make it an integral casting. This middle member comprises the main sup ort for the whole apparatus, and is widene at the ends 42 and 43 to make the support more stable. The member 34 presents half housings 44 for the bearings 45 of the shafts and as an upper portion 46 and a lower portion for the gears 48.

This mem er also carries the half housings 49 for the glands 50 and the middle ortions of the end casing walls of the diferent pairs of impellers. It forms a series conduit from the inlet of the first pump to the outlet of the last, and, both reservoir and outlet at 51, 52 for the temperature control compartments.

The operation of the individual pumps is well illustrated in Figures 4 and 5. The synchronously rotating impellers seal in front and in rear and radially in part against the respective walls of their caslngs. In the middle they radially seal against one another along strips of babbitt 53 dovetailed along each side of each blade. Successive charges of air, or of other fluid pumped, entrain at 54 between the outer semi-cylindrical walls and successive airs of blades and are thus swept to the delivery side of the pump, at 55, whence they travel across the to s 56 of the partitions, down along the series conduit between the shafts and across the bottoms 57 of the opposite partitions to the inlet of the next pump, and so on from pump to ump with pro gressively greater compression until finally delivered from the out et" of the last pump.

. The babbitt seal ofeach impeller against its mate provides a close in rfitt' and sealing between the impellers of'eac pair permitting high impeller velocities of rotation without material wear. -Such wear as does take place is, moreover, at the intermeshing gears rather than at the. impellers.

The lmpellers are keyed to the shafts at 58 and the-blades are hollowed for the sake of eater lightness.

e removable ortions of the bearing housings are provi ed with usual dowels for greater ease 1n accurate placement and are eld in place by stud bolts.

Leaka e alon the shafts is prevented by the lands 50 e bearings themselves are re erably of the Hyatt type which is well- Known and therefore not here specifically described. The usual caps 59 at the outer ends of the bearings prevent undue loss of oil at the bearings.

In the illustrations the widths of successive pairs of impellers (alon their axes) is made progressively sma ler by reason of progressive compression of the pumped fluid. This is preferably the arrangement when the pumped fluid is air or other gas in that the specific volume of the air or other gas progressively diminishes with successive compressions. Obviously however, when the multistage pump is for use with fluids substantially incompressible such as water or molasses or grease, this progressive reduction in spacing will ordinarily not be given to the pump.

The figures represent a pump for use with air, the inlet opening receiving the air directly from the surrounding room. It is of course evident that when used for other fluids than air suitableprovision is made for connecting to a supply pipe.

Passages 60 communicating with the liquid-receiving heat-treating chambers 29 and 30 in the semi-cylindrical casting to overflow at any convenient place. Where the temperature control medium is steam the pan 51 would be closed at the top but I have not considered'it necessary to illustrate this as it is merely the'obvious means for keeping the steam from escaping into the surrounding air and for maintainin it in intimate contact with the surface of the central casing.

Where the construction of the outer semicylindrical membels and the middle. mem' bar is sectional with flanged sectional castings bolted together, I prefer to locate the lines of division across the corresponding ends of successive pairs of impellers, and to form the gland housings integral with the adjoining end sections. Either or both of the end sections may be provided with semicylindrical compartments'for temperature control.

When used as an air compressor, as in the form illustrated, coolin will usually not be begun until after the rst stage and in the figures no cooling compartments areshown until after the first stage impellers; but when the duty is to be that of furnishing a high pressure supply of viscous liquid such as molasses it may be desirable to have these compartments or temperature control before the first stage as well as after the last.

The successive sections bolt together along radial flanges and bolt to the middle member 34 along longitudinal flanges 66.

Each pair of mating impellers, with its casin may be considered as compr1s1ng a comp ete single stage pump, the impellers of which exactl fit and seal against the inner walls of 1ts lateral semi-cylindrical pocket, against its mate and against the transverse partition walls 67 and 68 across the middle member 34'.

Walls 67 are closed to the floor with easy curves at 69 and Walls 68 closed to the roof with eas curves at 70 to form the series conduit etWeen the outlets and inlets respectively of successive stage impellers.

It will be evident that these easy curves at 69 and 70 result at once in very low frictional resistance from pump to pump and also provide spaces for the transverse passages 52 and 63 and a large bottom area for the reservoir 51.

In operation the shaft 19 is driven in any suitable way, and this in turn by means of the intermeshing gears 41 and 41 main tains these shafts and the mating pairs of impellers in synchronous rotation.

The pumped fluid, as air, progressively travels from the inlet of the first stage to the outlet from the last with progressive increase in pressure at each stage; and while thus progressing through the multi stages its temperature is regulated by surface contact with and surface radiation from the inner walls of the compartments for temperature control, the temperatures being progressively lowered or progressively raised according to existing need by controlling the wall temperature of the compartments through control of the temperature and rate of flow of a suitable fluid through these compartments. 1 7

While I have elected to illustrate but a single form, it will be obvious to those ski led in the art that the preferred form in any installation will vary with conditions of service, as for example with the presence or absence of need for tem erature regulation betweenista-ges'; with t e fluid -medium used (e. g. water or stem'n) for temperature regulation, or with any individual whim or particular need, varying andmodifyingthe structure and I intend to claim all such variations and modifieations in so far as they fall within the. zeasonable spirit and scope of my inven- Having thus described my invention, what I claim as new and desire to secure by Letters Patent is i 1. A multi-stage pump comprising a pair of single stage rotary pumps 'Root type, spaced axially of their parallel shafts to provide a space between them to art. as a channel, walls completing the limits of the channel and establishing communication between opposite extremities of said-channel and the outlet of one pump compartment and the inlet of the other, respectively, and means for heat-treating the fluid as it passes through the pump.

2. A pair of single stage Root type rotary pumps spaced axially of their parallel shafts, having the parts between the shafts in one piece and to provide a space between them as a channel, walls completing the channel and establishing communication from the outlet of one channel to the inlet of the other, said walls forming separate semicircumferential side members for earh of the two pumps, securing rigidity of the unit by the central member and permitting removal of the walls forming the side members for repairs and shaft replacement.

3. A pair of single stage Root type rotary pumps spaced axially of their parallel shafts,to provide a space between them as a channel, walls completing the channel and establishing communication from the out let of one channel to the inlet of the other,

said pumps and walls separating along longitudinal planes passing through the parallel shafts into middle portions and semicylindrical side portions, in combination with walls forming fluid receiving heattreating chambers in the said cylindrical side portions.

4. A pair of single stage Root type pumps spaced axially of their parallel shafts, to provide a space between them as a channel communicating from the outlet of one to the inlet of the other and having the pumps and the walls of the channel se arated along longitudinal planes passing t rough the parallel shafts into middle portions and semicylindrical side portions, in combination with walls forming compartments for heatchannel to affect the fluid pumped during.

- parallel s afts upon which the imellers are its passage from one pump to the next.

5. Two rotary ressure pumps relatively spaced and axial y in line, in combination with an intermediate section, comprising in its central part walls combining with the pumps to provide a passage from the inlet of one pump to the outlet of the other and in its outer arts walls forming a heat-treating section or the liquid pumped.

6. Two rotary pressure pumps, relatively spaced and axially in line, com rising two pairs of synchronously rotating impellers of the Root type within casings and on parallel shafts, in combination with an intervening conduit section included between the pumps and receiving at. one side the discharge of one pump and at an opposite side of the casing and of the conduit feeding the inlet of the other pump, and means included between the pumps for regulating the temperature of the conduit. section.

7. Two rotary pumps, relatively spaced and axially in line, comprising two pairs of synchronously rotating impellers within casings and on parallel shafts and an intervening conduit section included between the pumps, receiving, at one side of the casing and of the conduit the discharge of one pump and at an opposite side of the conduit and of the casing feeding the inlet of the other pump, in combination with compartments included between the pumps for fluid regulation of the temperature of the conduit.

8. A multistage pump, comprising a plurality of spaced pump sections each having a box-like central casing member between two semi-cylindrical side casings, a pair of parallel shafts within the sections and common to the several pumps, mating impellers of the Root type synchronously rotating and sealing against the end walls of the respective central casing member, with each other and with the walls of the semi-cylindrical side casing members, fluid compartments for temperature control carried by the semi-cylindrical side casing members and between adjoining pump sections, and extensions of the end walls between the central casing members of adjoining pump sections closing at one end of each wall and forming between the sectionsa chamber conduit between the outlets and inlets of the respective pump sections.

9. A multi-stage pump having a plurality of pairs of mating impellers of the Root type spaced along one pair of shafts and casing walls for each pair of mating impellers, 1n combination with walls uniting the casing walls of adjoining pairs of impellers to form between the shafts a conduit chamber to receive the discharge of one pair of impellers for delivery to the next pair, and to form outside of each shaft a compartment adapted to fluid regulation of temperature.

10. A air of impellers of the Root type mounted, a casin for the impelers comprising semi-cylin rical side sections-at opposite sides and o en'at one end transverse to the shafts an an intermediate section joinin 'them, in combination with another pair 0 impellers of the Root type mounted on the same shafts and spaced from the first, an impeller easing surrounding the second pair of impellers and havin a straight section between the shafts an semi-cylindrical side sections and each of the latter side sections having a semi-cylindrical fluid compartment for temperature regulation closing the open end of one of the first semicylindrical side casings sections on one side and easing one of the second im ellers upon the other, and closure walls etween the straight casing sections formin conduit connection between the outlet 0 of impellers and the inlet of the other pair of impellers.

11. A air of impellers of the Root type, parallel s rafts upon which the impellers are mounted, a casing for the impellers comprising a straight section between the shafts and semi-cylindrical side sections at opposite sides and each open at one end transverse to the shafts, in combination with a plurality of pairs of impellers of the Root type spaced from the first pair and from one another along the same pair of parallel shafts, a casing for each additional pair having a straight section between the shafts and semi-cylindrical side sections at op 0- site sides, each semi-cylindrical side sectlon having one end transverse to the shafts open and at the other end a semi-cylindrical extension forming a water cooling compartment adapted to case its own impeller upon one side and to close the open end of an adjoining semi-cylindrical casing upon the other, and closure walls joining successive straight sections to form conduit connection between the outlet and inlet of adjoining pairs of impellers.

12. A multi-stage blower comprising a plurality of complete Root type blowers spaced alon and upon the same pair of shafts and dlvided transversely to the shafts along planes at the ends of the impellers providing sections having open and closed ends, considered in directions parallel to the shafts, the open end of one section being closed by the closed end of the next.

13. A semi-cylindrical side casing member for a pump of the Root type comprising a semi-cylindrical casing adapted to fit the revolving blades of one of the impellers, in combination with a fluid compartment for temperature regulation in line with the casing in a direction parallel to the impeller shaft.

14. A semi-cylindrical side casing memone pair her for a pump of the Root type having along the impeller shaft one closed end and one open end, in combination with a second semi-cylindrical side casing member for a second and eo-axial pump of the Root type having along the impeller shaft :1 fluid chamber for temperature regulation form ing one end of its own impeller casing and adapted to close the open end of the first impeller casing.

spective spaced impellers along one of the I common shafts and the intermediate compartment adapted to fluid regulation of temperature.

THOMAS W. GREEN.

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