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Publication numberUS2142773 A
Publication typeGrant
Publication dateJan 3, 1939
Filing dateJul 30, 1938
Priority dateJul 30, 1938
Publication numberUS 2142773 A, US 2142773A, US-A-2142773, US2142773 A, US2142773A
InventorsIsaac H Athey
Original AssigneeIsaac H Athey
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Pump
US 2142773 A
Abstract  available in
Images(2)
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Claims  available in
Description  (OCR text may contain errors)

l. H. ATH EY Jan. 3, 1939.'

PUMP

Filed July 30, 1938 2 Sheets-Sheet l IIE llll Jan. 3, 1939.

I. H. ATHEY PUMP Filed July 30, 1938 2 Sheets-Sheet 2 retenus Janes, 193s i My' invention relates to pumps particularly A UNITED STATES PATENT oFFIcE mais applicatliscrul; gssio zzaovv 14 claims. (cl. ros- 51) adapted for use in deep oil wells and for similar purposes and has for a general object the provisionj of a. novel and improved pumpmechanism whose operation is automatic and is effected by -a continuous supply of compressed air or other gas at a constant high pressure.

Another object of my invention is to provide apump having means for positively discharging oil or other liquid from a pump chamber and additional means for aiding .the rise oi the liquid to the surface of the ground by lighteniuzigl the column of oil or other liquid.

v Another object of my invention is to provide an eiiicient pump of simple and. economical construction in which a maximum of work is accomplished for any given size of pump.

Another Vobject is. to provide a pump having y improved and simplied valve mechanism for controlling the operation of the pump.

The invention disclosed herein is an improvement on that disclosed in my prior application Serial No. 85,626 illed June 13, 1936. The instant application is a continuationinpart of my said prior application and contains all claims common to the two disclosures.

Other objects of my invention will appear as they are hereinafter disclosed and claimed and as set `forth in the accompanying drawings wherein Figure lA is a longitudinal cross-section of the pump mechanism showing the parts in the positions vvhicli they assume when the ,pump is discharging liquid from the pump cylinder;

Figure 1B is a longitudinal cross-section oi the structure forming a continuation of the upper end of Figul'elA;

Fig-ure 2' is a longitudinal crossf-secticn of the pump mechanism showing the parts in the posltions they assume during the intake stroke of the pump piston;

. l'lgure 3 is a transverse section through the valve mechanism and is taken on the irregular line 3 3 of Figure 1A;

Figure 4 is a vertical section through the air inlet valve and is taken on the irregular linev Figure 5 is a vertical section through the air discharge -valve and is taken on the irregular line 5 5 of Figure 3;

Figure 6 is a transverse section of a gas intake and is taken rou the line 6 5 of Figure 1B; land Figure 7 isa vertical section on the irregular line lof Figure 6 showing the gas intake.

In the drawings, the small broken arrows in,- dicate the ow of air, the small solid arrows indicate the ow of oil, andthe large solid ar. j rows indicate the direction of travel of thepiston.'

Referring to the drawings, I have indicated E; the pumping mechanism as being located in the well casing which is designated generally by reference numeral l0. It will he understood that when oil is iirst'struck, the pressure on the oil is usually sufficientl to raise this oil to the surface 1o of the ground in sucient quantities without the addition of any pumping mechanism. With the passage of time the pressure in the well becomes reduced and it is necessary to insert a pump in Y the casing of the weil 'tu bring the ou to the 1s' surface of the ground with the desired rapidity of ilow. When the pumping mechanism is rst inserted in the well casing, the natural level 'of the oil 'may be substantially the surface of the ground and as oil is continually withdrawn from 2o the well, the natural level o the oil recedes so that at suitable intervals the pumping mechansm must be lowered farther and farther down the casing of the well. As a general rule I preferably locate the pumping cylinder about a hun- 25 dredfeet below the natural level of the oil in the well, although it is to be understood that this. may be varied within any desired limits to conform to particular conditions or personal ideas with respect to the proper location oi the 3o pump cylinder, as my improved pump may loe located either immediately adjacent the surface oi the oil or any suitable distance therebelovr.

My novel pump comprises a pump cylinder it having an inlet check valve it adjacent its lower 35 end, the check valve heing'composed of a, hall l@ and seat it, the upper surface of the seat Vseing so inclined that the ball will roll by gravity into position to close the opening through the seat i3. The upper end of the cylinder l2 is o closed by a head 2d which contains the inlet and f discharge valves for the air or other operating uid.'

A piston 22 is reciprocably located in the pump cylinder l2 and carries a. reciprocable discharge s tube 2li through which the oil is discharged from the pump cylinder l2. This discharge tube has rigidly attached thereto, by threading or other suitable means, a second piston $5 o! smaller diameter than the piston 22 and-'located in an 50 air cylinder 2t which is threaded or otherwise attached to the ,head Ztl.

, The upper end of the reciprocable discharge tube 2B is in sealed telescopic relationship` with. a stationary discharge tube 3B which leads to the 65 surface o! the ground and through which the oil is discharged. The lower end of this discharge tube isthreaded or otherwise secured to a second head 82 which is'also in sealed engagement with the upper end of the air cylinder 28. The

stationary discharge tube 38 is provided with a valve seat 84 located at a' point just above the uppermostposltion reached by the upper end -of the reciprocable discharge tube 24. A gravityby threading or any other suitable means. The l air tube 38 surrounds and is of larger diameter than the discharge tube so that a space is yprovided therebetween through whioh the compressed air passes to the pumping mechanism. At suitable intervals in its length the stationary discharge tube 88 is provided with gas intakes indicated generally by reference character 40. Each gas intake comprises a valve member 42 suitably secured to the discharge tube 30 as by screws 4.4 and provided with a tapered end 46 forming the valve proper andnormally adapted to close the opening 48 in the discharge tube 30.

The valve member 42 is normally so biased that its tapered end 48 tends to move outwardly to uncover the opening 48 but this tapered end is normally held in closing position by the pressure of-the compressed air acting ony the outersurface of the tapered endof the valve member 42. The biasing of the valve member 42 can be set for any desired degree of bias by means of the adjusting screw 80. When the weight oi! the column of oil in the discharge tube 30 becomes great enough to exert a force on the inner surface of the tapered end 48 of valve member 42 to nearly balance the air pressure Aacting on the outer surface of this tapered end,

the valve member 48 moves away from its seat and permits compressed air to ow into the discharge tube 38. The air thus admitted to the thereto.

discharge tube 30 forms air bubbles in the oil above the opening 48, thus lightening the column of oil there-above and reducing the force which must be exerted by the pump piston 22 to raise vthe oil to the surface of the ground.

On each side of the gas intake valve 42 I preferably locate spacer members 52. These spacer members'52 provide sufficient local clearance between the discharge tube 3|) and the air tube 38 to permit the necessary movement of the tapered end 48 of valve member 42. It will-be understood that the gas intakes 40 are located at suitable intervals along the discharge tube 3! and that the number of such gas intakes increases as the pump is lowered in the well.

The compressed air or other gas forced down the air tube 38 passes through suitable openings 54 in the head 32 to the annular space 56 provided between the air cylinder 28 and a sleeve 58 which surrounds this air cylinder in spaced relationship municates with the yoke-shaped ports ,88 which cooperate with the'inlet valve 62 for controlling admission of air to the upper end of pump cylinder I2 and to the air cylinder 28.

As best shown in.l Figure 4., the yoke-shaped ports have lower outlets 84 adapted to communicate with vertical passage 86 when the inlet The lower end of this space 56 com-4 valve 82 is in the position shown in Figure 4. When the valve 82 is shifted to its other extreme position, the central rectangular portion o! the valve cuts oi! communication between outlets 84 and the passage 88 and simultaneously opens i communication between the upper outlets 88 and passage l0 leading to the lower end of air cylinder 28.

The extreme positions of the valve member 82 are'determined by washers 12 vand 14 which are held in place by nuts 18 and 18 respectively. The passages 88 and 'I0 are rectangular 4in cross-section so that the washers 1.2 and l'4 overlie the sides of these passages and contactrespectively with the lower and upper sides oi the head 28. The valve member 82 is held in either of its two extreme positions by the differential air pressures acting on opposite sides thereof. I shall presently describe the means for shifting the valve member between its extreme positions.

When the air inlet valve 82 is in the position shown in Figures 1 and 4, the compressed air is admitted to the upper end of the pump cylinder i2 above the piston22. This drives the piston 22 and discharge tube 24 downwardly as indicated by the large arrow in Figure l. The check valve i4 at the lower end of thepump cylinder is closed and the oil beneath the piston 22 is forced upwardly through discharge tube 24, check valve. 34, and rigid discharge tube 80, as indicated by the small solid arrows in Figures 1A and 1B.

At the same time, the smaller piston 28 is moving downwardly and discharging the air therebeneath through the air discharge valve mechanism located in the head 28 and into the annular space 80 between the well casing |50 and the outside of the pump cylinder l2, head 20 and sleeve 58, this annular space preferably averaging about a quarter of an inch. l

As best shown in Figures 3 and 5, the air discharge valve mechanism comprises a reciprocable valve member 82 having rectangular passage closing portions 84 and 88. During the discharge stroke of the pump the valve portion 84 is clear of the upper end of the vertical passage 88, thus permitting air to ow from the lower end of the air cylinder 28 into this passage and thence through lateral ,ports 90 to the annular space 80. At the same time the lower valve portion 88 closes ,communication between the lower end of the passage 88 and the upper end of the pump cylinder l2. The force of the air beneath the lower end of the valve member 82 holds the annular Washer 92 in engagement with the lower side of the head 2li where this washer overlaps the sides of the rectangularpassage 88. The washer 92 is secured to the valve member 82 by nut 94. The upper end of the valve member S2 is similarly provided with an annular washer 96 and nut @B which limit the downward movement of the valve member when shifted in a manner to be presently described;

When the piston 26S approaches the lower end of its stroke, the nuts attached to the upllci ends of the valve members 62 and iii?. are'engaged by the coil spring Hill which functions 'to shift these valve members to their other cxtreme positions as the piston reaches the downward limit of its stroke. The spring teil is formed of a at strip of spring metal and is suitably secured to the air piston 28' for recinrocation therewith.

After the air valve members 82 and 82 have been thus shifted, they assume the position shown in Figure 2. lin this position of these valves, compressed air is adniitted to the lower and of air cylinder 28 where it acts on the underside of piston 26 to raise this pistou,y the reciprocable discharge tube 24 and piston 22 thereby sucking oil into the pump cylinder I2 through the oil inlet valve l as indicated in Figure 2.. It will he noted that air cylinder 28 and piston 2o are of smaller diameter than pump cylinder l2 and piston 22 so that a smaller quantity of air sulllces 'to operate the pistons on the oil intake stroke.

This ,results in a material saving since less power is needed to operate the pumping mechanism on this stroke.

During the'upward stroke of pistons 22 and 25 the air in the upper end of the pump cylinder l2 is discharged through passages 858 and @il into the annular space 3B surrounding the pump cylinder and sleeve 58. During the upward stroke of the pistons the air in the space 92 between the air piston 26 and the head $2 is compressed. This space 6&2 is made of such length that in the normal operation of the mechanism the air in-this space expands and contracts as the piston E@ falls and-rises.. The passage los which liti 'lli

connects'tlie upper end of the space iElZ with the annular space to@ between the Well casing and the air tuhe de is provided with a check valve having a relatively strong spring which normally maintains this check valve in closed position during both strokes of the piston 26. The

solo purpose-oi the check valve idd is to act as a relief valve to prevent the pump from becomingl locked due' to leakage of air past the piston tic. n case sufficient lechage oi' air occurs past the piston 2d to raise the pressure in the space: E522 apprcciahly alcove that normally existing therein when the piston 2S? isat the upper limit of its stroke, the valve idd will open as indicated in ligme 2 to release this excessive pressure.

the pistons 22 land 2li approach the upper end of their stroke, the spring i tit engages the lower ends ci. valve members S2 and d2 and raises these valve members to their entre-me upward positions, as shown in Figure i, whereupon the direction of tre-.voi ci the pistons is reversed. fis previously explained, the valve members di* and @t are so arranged with respect to their cooperating ports, that these valve meschers are held in either of their extreme positions by the dierential pressures acting thereon,

The operation of my improved pumping mecheinem is entirely automatic. Aitil that is necessary is to hun on the comprmsed air, whereupon the pump will continue to operate until the compressed air is again out cfr?. Bue to vthe simplicity and ruggedness ci the parts, my improved pump is extremely durahie and requires a minimuni of attention. My pump also has the advantage of being extremely economical in its utilisation oi the compressed air or other opergss. Y

When the parts are in the. positions shown in Figures is and iE and' the compressed air is turned on, the compressed air dows down the space between the air tube 3S and the discharge tune di?, @rough the passages iid in head si, through the annular space d and through ports and @d and passage to the upper end oi pump cylinder il. The air' thus admitted to the pump'cylinder forces down the piston 22, whereupon the oil in the pump cylinder' is forced upwardly through the reciprccable discharge tube dit, past valve Ed, and through discharge tube cil to the surface of the ground where it may be stored in tanks or otherwise suitably disposed of.

.es the oil piston 22 descends, the air piston 12d f arves likewise descends, the air ahead of the piston being discharged through passages 88 and 90 into the annular space between the pumping mechanism and the casing of the well. As the piston 26\descends, the air in the space W2 thereabove expands, thereby reducing the pressure existing in this space.

As the pistons 22 and 26 approach the lower ends of their stroke, the spring |00 shifts they valve members of the air inlet and discharge valves, thereby admitting air under pressure to the lower end of the air cylinder 28 and permitting the discharge of air from the upper end of the pump cylinder l2 into the annular space 80. As the pistons 22 and 2E move upwardly, oil is drawn in from the well, through the check valve M as shown in Figure 2. During the upward. stroke oi' the pistons, the air in the space 02 is compressed, but under ordinary circumstances the compression of this air even at the extreme upward position of the piston 26' is not sumcient to open the check valve 108. 'When the pistons 22 and 26 approach the upper ends of their stroke,

.the spring il@ engages the lower ends of the air inlet and discharge valves and shifts them hack to the positions shown in Figure lA, whereupon the cycle is repeated.

When the pumping mechanism is located a considerable distance below the surface of the ground and the pressure of the column of oil above any one or more of the gas intakes @il becomes suiciently great, the: tapered ends do of' the valve members i2 move to open position and admit compressed air which forms bubbles in the column of oil thereabove and thus lghtens this column, thereby reducing the force which the pump piston 22 must exert to raise the oil to the smface.

During the poing operation it is only necessary that my novel pump ce connected to a source ci air or other gas under si'sdcient pressure to raise the oil or other liquid to 'the surface of the ground. 'its operation thereafter is entirely automatic, requiring no attention or esternal operation whatsoever. in the event that the pressure in the well itself is sufficient te raise the oil or other liquid to the surface without aid from the pump, the air suppiy may he cut ofi, whereupon the oil or other liquid itself will open the check valves id and dfi and dow to the surface.

While my invention is primarily designed ior use inoil wells and has been so described, its use is not so limited and it may be used in other types of wells. My invention is not limited to the details shown and described, hut may assume numex-ous forms within the scope o the appended gas cylinder, a rigidV discharge tube connected to' said last-named head and telescopica with said hrm-named discharge tube, inlet and discharge valves for said liquid cylinder, a. gas conduit surrounding said rigid discharge tube and gas cylinder, a valve for connecting said gas conduit alternately with said cylinders, said gas conduit and pump cylinder being spaced from the well casing, a discharge valve for cormecting said cylinders alternately with the space thus formed,

a spring recprocable with each piston for shift-1- ing said gas inlet and discharge valves, said lastnamed valves being located in said rst-named head and being designed to be held in either extreme position by the differential pressures acting on opposite sides thereof, and a relief valve for said gas cylinder.

2. In a pump mechanism for wells having casings, the combination of a liquid cylinder and a conduit and pump cylinder being spaced from the well casing, and adlscharge valve for connecting said cylinders alternately with the space thus formed, a spring reciprocable with each piston for Vshifting said gas inlet and discharge valves, said valves being located in said rstnamed head and being designed to be held in either extreme position bythe diierential pressures acting on opposite'sidesthereoi'.

3. In a. pump mechanism for wells having casings, the Ycombination of a liquid cylinder and a gas cylinder having a common head, a piston in each cylinder, a discharge tube connecting said pistons and extending through said head, a second head at the upper end of said gas cylinder, a rigid discharge tube connected to said last-named` head and telescoping with said ilrstnamed discharge tuba-inlet and discharge valves -for said liquid cylinder, a gas conduit surrounding said rigid discharge tube and gas cylinder, a valve for connecting said gas conduit alternately with said cylinders, said gas conduit and pump cylinder being spaced from the well casing, a discharge valve for connecting said cylinders alternately with the space thus formed, and a spring reciprocable with each piston for shifting said gas inlet and discharge valves, said valves being located in said rst-named head and being designed to -be held in either extreme position by the diierential pressures acting on opposite sides thereof.

' 4. In a pump mechanism for wells having casings, the combination of a liquid cylinder and av gas cylinder having a common head, a piston in each cylinder, a discharge tube connecting said pistons and extending through said head, a second head at the upper end oi said gas cylinder, a rigid discharge tube connected to said last-named head and telescoping with said first-named discharge tube, inlet and discharge valves for said liquid cylinder, a gas conduit, a valvefor connecting said gas conduit alternately with said cylinders for supplying pressure fluid to the sides of the pistons facing the common head, a discharge valve for connecting ysaid cylinders alternately withga gas outlet, and a relief valve for said gas cylinder.

5. In a pump mechanism for wells having casings, the combination of a liquid cylinder and a gas cylinder having a common head, a piston in each cylinder, a discharge tube connecting said pistons and extending through said head, a second head at the upper end oi said gas cylinder, a rigid discharge tube connected to said' last-named head and telescoping with said ilrstnamed discharge tube, inlet and discharge valves for said liquid cylinder, a gas conduit, a valve for connecting said gas conduit alternately with said cylinders, said gas conduit and pump cylinder being spaced from the well casing, a discharge valve for connecting: :aid cylinders alternately with the space thus formed, and spring means' for shifting said air inlet and discharge valves, said valves being located in said first-named head and being designed to be held in either extreme position by the differential pressures acting on opposite sides thereof. A

6. In a pump mechanism for wells having casings, the combination of aliquid cylinder and a gas cylinder, a piston in each cylinder, inlet and discharge valves for said liquid cylinder, a gas supply conduit, a valve for connecting said gas conduit alternately with said cylinders, said gas conduit and pump cylinder being spaced from the well casing, a discharge valve for connecting said cylinders alternately with the space thus formed, aspring reciprocable with each piston for shifting said gas inlet and discharge valves, said valves being designed to be held in either extreme position by the diierential pressures acting on opposite sides thereof, and a relief valve for said gas cylinder.

7. In a pump mechanism for wells having casings, the combination of a liquid cylinder and a gas cylinder having a common head, a piston in each cylinder, a reciprocable discharge tube connecting said pistons.' a second `head at the upper end of said gas cylinder, a rigid discharge tube connected to said last-named head and telescoping with said first-named discharge tube, inlet'and discharge valves for said liquid cylinder, a gas conduit, a valve for connecting said gas conduit alternately with said cylinders, a discharge valve for said cylinders, and a spring reciprocable with each piston for shifting said air inlet and discharge valves, each spring comprising a coil of flat material and surrounding said reciprocable discharge tube.

8. In a pump mechanism of the class described, the combination of a pairy of cylinders, a common head for said -cylinders and an inlet valve located in said head, said lmet valve comprising a passagev vpassing entirely through said head, said passage having end portions `which are rectangular in cross-section,l a transverse passage connecting said first-named passage'with a source of gas under pressure, and a valve member located in said first-named passage and having end portions -of rectangular cross-section to conform to the charge valve comprising a passage of rectangular cross-section extending through said head, a

. yoke-shaped passage in said head connecting said first-named passage with a discharge outlet, and a valve member movable in said rst-named passage, said valve member having an enlarged section of rectangular cross-section for controlling communication between said first-named passage and said yoke-shaped passage, reduced end portions, and a circular memberattached to each end and overlapping the sides `of saidiirst-named passage whereby said circular memamarre Y bers limit the movements oi said valve member.

.10. In a pump mechanism of the class described, the combination of a pair oi' cylinders, a head common to said cylinders and a discharge valve for said cylinders located in said head, said vdischarge valve comprising a passage extending through said head, a yoke-'shaped passage in said head connecting said iirst-named passage with a discharge outlet, and a valve member movable in saidiirst-named passage, said valve member having an enlarged section for controlling communication between said iirstnamed passage and said yoke-shaped passage, reduced end portions, and a stop member attached to each end and overlapping the sides of said mst-named passage whereby said stop .Y members limit the movements of said valve member.

11. In a pump mechanism of the class described, the combination of a pair of cylinders, a'common head for said cylinders, an inlet valve located in said head, said inlet valve comprising a passage passing entirely through said head,

i ,said passage having end portions .whlchare rectangular in cross-section, a transverse passage connecting said first-named e with a source oi' gas under pressure and a valve member located in saidiirst-named passage and having end portions of rectangular cross-section to conform to the ends of said first-named passage, a central portion of reduced cross-section, and

a circular member attached to each rectangular portion, said circular members having a diameter greater than the shorter side of the ends of said rst-named passage whereby said circularportions limit the movements of said valve member. and a discharge valve for said cylinders located in said head, said discharge valve comprising a passage ofrectangular cross-section extending through said head, a yoke-shaped passage in said headconnecting said first-named e with a discharge outlet and a valve member movable in said rst-named passage, said valve member having an enlarged section oi' rectangular crosssection i'or controlling communication `between said mst-named passage and said yoke-shaped passage, reduced end portions, and a circular member attached to each end and overlappingl the sides of said rst-named passage whereby said circular members limit the movements of said valve member.

12. In a pump mechanism of the class dev under the iniiuence of said springs.

13. In a pump mechanism of the class de` scribed, the combination of a pair of cylinders, a head common to said cylinders, inlet and discharge valves for said cylinders located in said head, a piston reciprocaole in each cylinder, a

coiledspring formed of flat material carriedby each piston and adapted to engage and shift said valves, and means carried by said valves to limit the movement thereof under the inue'nce of said springs.

'14. In a pump mechanism for wells having casings, the combination of a liquid cylinder and a gas cylinder having a common head, said gas cylinder being of smaller diameter than said liquid cylinder, a piston in each cylinder, a discharge` tube connecting said pistons and extending through said head, a second head at the upper end of saidl gas cylinder, a rigid discharge tube connected to said last-named head and telescoping withsaid ilrst-named discharge tube, inlet and discharge valves for said liquid cylinder, a gas conduit, a valve i'or connecting said gas conduit 'alternately'with said cylinders for supplying pressure iluid tothe sides of the pistons facing the common head, a discharge valve for connecting said cylinders alternately with a gas outlet, and a relief valve for said gas cylinder.

ISAAC ATHEY.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2991721 *Oct 7, 1957Jul 11, 1961Hubert L FosterPump
US4421463 *Jul 8, 1981Dec 20, 1983Jeff D. MorganDownhole pump
US5911278 *Jun 20, 1997Jun 15, 1999Reitz; Donald D.Calliope oil production system
US6435838Aug 17, 2000Aug 20, 2002John E. MarvelFluid well pump
US6558128Jul 9, 2002May 6, 2003John E. MarvelFluid well pumping system
US6672392Mar 12, 2002Jan 6, 2004Donald D. ReitzGas recovery apparatus, method and cycle having a three chamber evacuation phase for improved natural gas production and down-hole liquid management
US6810961Jan 21, 2003Nov 2, 2004John E. MarvelFluid well pumping system
US7080690Jun 6, 2003Jul 25, 2006Reitz Donald DMethod and apparatus using traction seal fluid displacement device for pumping wells
US7100695Nov 3, 2003Sep 5, 2006Reitz Donald DGas recovery apparatus, method and cycle having a three chamber evacuation phase and two liquid extraction phases for improved natural gas production
US20040123987 *Nov 3, 2003Jul 1, 2004Reitz Donald D.Gas recovery apparatus, method and cycle having a three chamber evacuation phase and two liquid extraction phases for improved natural gas production
US20040244991 *Jun 6, 2003Dec 9, 2004Reitz Donald D.Method and apparatus using traction seal fluid displacement device for pumping wells
US20050279493 *Nov 2, 2004Dec 22, 2005Marvel John EFluid well pumping system
Classifications
U.S. Classification417/392, 91/268, 91/341.00R, 91/341.00A, 91/272, 91/329
International ClassificationF04B47/04
Cooperative ClassificationF04B47/04
European ClassificationF04B47/04