Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.

Patents

  1. Advanced Patent Search
Publication numberUS3638499 A
Publication typeGrant
Publication dateFeb 1, 1972
Filing dateMay 13, 1969
Priority dateMay 13, 1968
Also published asDE1924502A1, DE1924502B2, DE1924502C3
Publication numberUS 3638499 A, US 3638499A, US-A-3638499, US3638499 A, US3638499A
InventorsRobert Saint-Andre
Original AssigneeRobert Saint Andre
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Device for sampling fluid of hydraulic circuit
US 3638499 A
Abstract
A device for taking samples of fluid from a hydraulic circuit while operating under pressure comprises a hollow body having a chamber which is connected into the circuit through a very small opening which is normally closed by a point at the end of a spring-pressed plunger slidable in the chamber and having near its point lateral channels leading into a central longitudinal channel through which the sample is discharged when the plunger is pulled down against its spring so as to open the opening. A controlled-leakage passage prevents accumulation of solid particles and keeps the device clean so that subsequent samplings are not contaminated.
Images(1)
Previous page
Next page
Description  (OCR text may contain errors)

United States Patent 1151 3,638,499 Saint-Andre Feb. 1, 1972 [54] DEVICE FOR SAMPLING FLUID 0F 2,973,123 2/1961 Rousset ..222/51s x HYDRAULIC CIRCUIT 2,994,224 8/1961 Brown ..73/422 3,091,374 5/1963 Schwartzman ..222/518 X [72] Inventor: Robert Saint-Andre, 95, av. de Naugeat,

87 Limoges, France FOREIGN PATENTS OR APPLlCATlONS [22] Filed: May 13, 1969 1,293,911 6/1961 France ..25l/DlG. 4

[21] APPLNOJ 824l72 Primary Examiner-Louis R. Prince Assistant Examiner-Daniel M. Yasich 3 Foreign Applicmion priority Data AttorneyR0bert E. Burns and Emmanuel .l. Lobato May l3, I968 France ..l5l567 57 ABSTRACT 1521 us. 01 ..73/422 R, 251/010. 4 A device for taking Samples of fluid from a hydrauliC circuit [51 I Int. Cl. ..G0ln l/l0 operating under P comprises a hollow body [58] Field of Search ..73/422 R; 251/354, 522, 348; ing a Chamber which is connected the circuit through 222/518 very small opening which is normally closed by a point at the end of a spring-pressed plunger slidable in the chamber and 56 Ref Cted having near its point lateral channels leading into a central erences I longitudinal channel through which the sample is discharged UNITED STATES PATENTS when the plunger is pulled down against its spring so as to open the opening. A controlled-leakage passage prevents ac- 770,043 9/1904 Bode et al ..l37/522 cumulation of Solid particles and keeps the device Clean so 1 988,181 l/ 1935 spaeth that subsequent samplings are not contaminated. 2,012,836 8/1935 Talbot et al... 2,844,964 7/1958 Guibert ..73/422 9 Claims, 4 Drawing Figures Q11 is Z '10 8 m Q %R s IS l1 PATENTED rm 1 1912 DEVICE FOR SAMPLING FLUID OF HYDRAULIC CIRCUIT The present invention relates to a device for taking samples of the fluid ofa hydraulic circuit.

It is frequently necessary to take samples of the fluid of a hydraulic circuit under pressure in order to examine the state of the hydraulic fluid to check on its state of cleanliness and to carry out physical and chemical analysis. Such sampling should be effected during operation of the machine so that any impurities will be in suspension. If a sample is taken of the fluid while the machine is at rest, any impurities will have been deposited and the sample will not give true results. As an example, such sampling should be frequently carried out on hydraulic circuits of aircraft.

In order to effect such samplings, there have been utilized according to prior techniques arrangements of valves and couplers which are subject the double inconvenience of not being practical at the high pressures under consideration and of leaking. This is why, on modern circuits, sampling is effected by means of a movable member which is displaced to an unblocking position by the pressure of the fluid against the opposition of an elastic member. Thus, there is known an arrangement in which a closing valve under the force of an opposing elastic member calibrated to the pressure prevailing in the circuit opens the sampling orifice when the cap which blocks it in closed position is unscrewed. The body of the valve carries a helix in relief. Its diameter is very near the inside diameter of the sampling chamber. The existence of the spiral and the small space between the body of the valve and the interior wall of the chamber is for the purpose of reducing the effect of the high pressure of the fluid. The fluid is thus constrained to flow along the spiral. However, this precaution is not sufficient and the functioning of this device is poor for pressures higher than 300 or 400 atmospheres. Furthermore, over a period of time the lubricant soils the spiral so that sub sequent samplings of fluid, in themselves quite proper, appear to be dirty.

In another device of the same sort, the valve is simply subjected to the force of an opposing elastic body supported on an internal shoulder in the sampling chamber. This elastic member is thus submitted directly to the high pressure of the fluid which limits the possibilities of using the apparatus. MOreover. in this second variant, the fluid soils the springs and thus contaminates subsequent samples. The excessive size of dead spaces without circulation causes an accumulation of pollutants.

The present invention overcomes these objections. It is an object of the invention to take samples of hydraulic circuits under pressure characterized by the fact that it is formed as a hollow body of which the chamber is put in communication with the hydraulic circuit by an orifice which is of very small diameter and is closed by the point of a needle valve member which is pierced by a lateral canal opening into a central canal, the movement of the member toward the base of the needle assuring opening of the orifice, the passage of the fluid into the chamber of the hollow body and its sampling by the lateral canals and central canal to the base of the needle valve member.

The liquid is thus never in contact with any springs or other mechanism since it passes directly to the base of the needle valve member in the canals where it cannot pick up any impurities. This assures the neutrality of the apparatus with respect to subsequent samplings.

The chamber of the hollow body preferably conforms closely to the form of the point of the needle valve member so that the dead space will be reduced as much as possible and the walls will be very nearly vertical so as to avoid all deposits. Moreover, a leakage passage is provided so that the liquid is not retained in the dead space and the leakage circuit thus assures a constant cleaning of the apparatus.

The invention will be more fully understood from the following description with reference to a nonlimiting example illustrated in the annexed drawings in which:

FIG. I is a generally vertical section of apparatus according to the invention;

FIG. 2 is a detailed section of a first closing device of the leakage passage;

FIG. 3 is a detailed section ofa second closing device of the leakage passage, and

FIG. 4 is a partial section along the line IVIV of FIG. 1.

With reference first to FIG. 1, the apparatus will be seen to comprise a body I having an interior chamber 2 in which a cylindrical plunger or needle valve member 3 provided at its upper extremity with a point 4 is displaceable. The chamber 2 of the body 1 is put in communication with the hydraulic circuit where a sampling is to be effected by an orifice 5 of very small diameter. By way of example and without any limitation, the diameter of this orifice selected according to the pressure of the circuit and of which the narrowness has for its object the avoidance of too great a discharge of fluid, is of the order of 0.25 mm. The orifice 5 is placed in the vicinity of the center of the fluid vein where the fluid is in a zone of high velocity.

The orifice 5 is closed by the upper extremity of the point 4 when the member 3 maintained in its uppermost position by being resiliently supported on a collar 6 resting on a cap 7 which closes the lower end of the chamber 2. The cap 7 is screwed onto the body I by threads 8.

A compression spring 9 is supported by the collar 6 and the upper end of the spring engages a collar 10 which is fixed on the member 3. The spring 9 is calibrated in such manner that the force it exerts on the member 3 is approximately equal to or slightly greater than the force exerted by the pressure of the fluid in the circuit, the calibration being effected when the cap 7 is unscrewed so that a shoulder 6a of the collar 6 comes to rest on an abutment 11 in the body 1.

When the cap 7 is screwed on, the spring 9 is thereby tightened to assure absolute security.

The member 3 is pierced near its point by lateral canals l2 and 13 which opens into the upper end of a central canal 14 extending down to an outlet 16 at the bottom of the member 3 below the lower end of the body 1. The walls of the chamber 2 are so constructed as to be as close as possible to the point 4 in order to leave only a small dead space 2 communicating with the exterior by a leakage circuit 15.

When it is desired to effect a sampling, the cap 7 is completely unscrewed and removed whereupon the shoulder 6a of the collar 6 comes to rest on the abutment II, the spring 9 still exerting a sufficient force opposing the fluid pressure of the circuit on the member 3 to prevent discharge through the orifice 5. The member 3 is then manually forced downwardly so that fluid can escape through the orifice 5, the lateral channels l2 and I3 and the central channel 14 and can be sampled by the outlet 16 of the member 3. The cap 7 is provided with a recess 7a which can, if desired, be used to catch the fluid escaping through the outlet 16.

According to an important industrial advantage of the invention, the fluid is not in communication with an mechanism such as the spring 9. It passes for the most part in the central channel 14 where no deposit of solids can occur, thereby assuring the neutrality of the apparatus with respect to future samplings. It is to obtain this advantage that the volume of the dead space 2' is reduced to a minimum. A small part of the fluid escapes by the leakage passage 15. This escapement further reduces the formation of deposits in the dead space 2 and assures that it stays perpetually clean.

Packings l8, 19, etc., are used at the joints to avoid all parasitic leakage.

FIGS. 2 and 3 show two possible arrangements for closing the leakage passage 15. The first arrangement, shown in FIG. 2, is a simple needle valve 20, manually manipulated by a knurled button 21, closing the orifice 15 of the leakage passage 15. A stop I5" prevents the needle from being screwed completely out.

The second variant, as illustrated in FIG. 3, comprises a pressure responsive valve 22 subjected to the force of a spring 23 supported by a small collar 24 blocked by an abutment 25.

The said valve 22 closes a canal 15 of the leakage passage [5 and assures the escape of fluid by the channel when the pressure of fluid in the canal 15' is sufficient to open the valve 22 against the force of the spring 23.

The description of these two arrangements is not intended to be limiting since there are other ways of closing the leakage passage 15.

The leakage passage provides a means of achieving a circulation in the mechanism without contact with the liquid which is sampled by means of the central canal l4 and the outlet 16.

The system of closing the leakage passage such as that illustrated in FIGS. 2 and 3 or any other system, is for the purpose of preventing the oozing of liquid due to the accidental imperfect closing of the point 4 on its seat. It will be seen that the valve member 3 such as that represented is large with respect to the actual dimensions of the dead space by the order of tens of cubic centimeters. in the arrangement used heretofore the dead spaces were in general so great as to cause the risk of deposit of solids and of contaminating subsequent samplings.

With reference to FIG. 4 it is seen that the cap 7 can be provided with a lateral projection 26 having a notch 27 of a size to slip over the above member 3 above the shoulder 28. When the cap has been removed, it is possible by means of the notch 27 to pull down on an annular shoulder 28 provided on the stem of the member 3 and thereby open the orifice 5. This detail of construction is designed to simplify use of the apparatus, it being understood that it is not intended to be limiting and it is not necessary to the functioning of the apparatus according to its fundamental characteristics.

What] claim is:

1. A device for taking a sample of the fluid of a hydraulic circuit while operating under pressure which comprises a hollow body having a chamber communicating with said circuit by a small diameter orifice, a collar slidable in said chamber, a

reciprocable plunger slidable in said collar and having at one end a point engageable in said orifice to close it, a central channel extending through said plunger to the opposite end of said plunger and at least one lateral channel opening from said central channel into said chamber near said point, means for limiting movement of said collar in a direction away from said orifice, compression spring means surrounding said plunger and acting between said collar and said plunger for urging said plunger toward said orifice to close said orifice by said point, said spring means being calibrated normally to exert on said plunger a force greater than the force exerted on said plunger by the pressure fluid of said hydraulic circuit, said plunger being retractable against the force of said spring means to open said orifice and permit a sample of hydraulic fluid to flow through said channels and to be discharged from said opposite end of said plunger.

2. A sampling device according to claim I, further comprising a cap screwed onto an end of said body opposite said orifice and engageable with said collar to move it toward said orifice and thereby increase the pressure exerted on said plunger by said spring.

3. A sampling device according to claim I, in which said plunger conforms closely to the walls of said chamber so as to avoid excessive dead space in which solid particles can collect.

4. A sampling device according to claim 1, in which a removable cap closes an end of said hollow body opposite said orifice, and in which said cap includes means engageable with said plunger to retract said plunger and thereby open said orifice.

5. A sampling device according to claim 1, comprising a by a small diameter orifice, a plunger reciprocable in said c amber and having at one end a point engageable in said on fice to close it, a central channel extending through said plunger to the opposite end of said plunger and at least one lateral channel opening from said central channel into said chamber near said point, spring means for urging said plunger toward said orifice to close said orifice by said point, said spring means being calibrated normally to exert on said plunger a force greater than the force exerted on said plunger by the pressure fluid of said hydraulic circuit, said plunger being retractable against the force of said spring means to open said orifice and permit a sample ofhydraulic fluid to flow through said channels and to be discharged from said opposite end of said plunger, said plunger conforming closely to the walls of said chamber so as to avoid'excessive dead space in which material can collect, said body being provided with a

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US770043 *Nov 9, 1903Sep 13, 1904Paul BodeSafety-valve.
US1988181 *Apr 5, 1933Jan 15, 1935Universal Merit CorpStorage tank gauge
US2012836 *Feb 9, 1933Aug 27, 1935Texas CoSampling device
US2844964 *Dec 6, 1952Jul 29, 1958Guibert Francis WLiquid sampler
US2973123 *Apr 16, 1958Feb 28, 1961Sparklets LtdFluid dispensing means
US2994224 *Sep 15, 1958Aug 1, 1961Jersey Prod Res CoFluid sampler
US3091374 *Jul 28, 1960May 28, 1963Glidomatic CorpLiquid metering device
FR1293911A * Title not available
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3812545 *Jul 17, 1972May 28, 1974Dyna Logics IncAdjustable toilet tank flush valve
US4484482 *Dec 16, 1982Nov 27, 1984Aeroquip CorporationFluid sampling valve
US4549440 *Mar 29, 1984Oct 29, 1985Aeroquip CorporationFor internal combustion engines
US4580453 *Nov 13, 1984Apr 8, 1986Taylor Julian SGear case oil sampler
US4681138 *Jul 25, 1985Jul 21, 1987Veca S.R.L.Valvular device for the inflation of balloons, particularly balloons supported by tubular shafts
US4877065 *Mar 16, 1983Oct 31, 1989Wella AktiengesellschaftDecanting device for liquids, e.g. permanent wave agents
US5296197 *Jul 9, 1992Mar 22, 1994Nl Technologies, LimitedAutomated sample extractor or feeder/inoculator for bioreactors and similar equipment
US5525301 *Mar 21, 1994Jun 11, 1996Nl Technologies, Ltd.Actuator comprising connector to forward valve operating rod including rear valve operating rod, trigger for manually moving rod operatively connected to rear valve rod and pivotable about pivot axis, leverage adjustment means
US5786209 *Mar 12, 1996Jul 28, 1998Nl Technologies, Ltd.Automated sample extractor or feeder/inoculator for bioreactors and similar equipment
US5880380 *Apr 29, 1997Mar 9, 1999Goldschmidt; NormanHigh containment sampler
US6133022 *Jul 27, 1998Oct 17, 2000Nl Technologies, LimitedAutomated sample extractor or feeder/inoculator for bioreactors and similar equipment
US6821773Oct 16, 2000Nov 23, 2004Nl Technologies, Ltd.Drainable ferrule valve design
US7293475May 1, 2006Nov 13, 2007Millipore CorporationDisposable, pre-sterilized fluid receptacle sampling device
US7293477Dec 23, 2003Nov 13, 2007Millipore CorporationDisposable, pre-sterilized fluid receptacle sampling device
US7578205May 26, 2006Aug 25, 2009Millipore CorporationSterile sampling device
US7921740Jul 20, 2007Apr 12, 2011Millipore CorporationDisposable, pre-sterilized fluid receptacle sampling device
US7927316Apr 25, 2003Apr 19, 2011Millipore CorporationDisposable, sterile fluid transfer device
US8517998Apr 22, 2011Aug 27, 2013Emd Millipore CorporationDisposable, sterile fluid transfer device
US8539988Dec 15, 2009Sep 24, 2013Emd Millipore CorporationDevice for the transfer of a medium
US8544497Oct 12, 2010Oct 1, 2013Emd Millipore CorporationFluid transfer device and system
US8549935Sep 24, 2008Oct 8, 2013Emd Millipore CorporationDisposable, pre-sterilized fluid receptacle sampling device
US8562572Feb 8, 2006Oct 22, 2013Emd Millipore CorporationDisposable, sterile fluid transfer device
US8579871Oct 20, 2006Nov 12, 2013Emd Millipore CorporationDisposable, sterile fluid transfer device
US8646342Aug 31, 2010Feb 11, 2014Emd Millipore CorporationDisposable, pre-sterilized fluid receptacle sampling device
US8690120Nov 13, 2008Apr 8, 2014Emd Millipore CorporationFluid transfer device
DE102010060241A1 *Oct 28, 2010May 3, 2012Hecht Technologie GmbhProbe receiver for removal of sample of powder or bulk material, has pump port that attaches pump to production of low pressure such that sample is pneumatically separable over terminal from storage device
WO2004055512A1 *Dec 9, 2003Jul 1, 2004Zahnradfabrik FriedrichshafenDevice and method for testing a transmission
Classifications
U.S. Classification73/863.86, 251/903
International ClassificationG01N1/10, G01N1/28
Cooperative ClassificationG01N2001/105, G01N1/10, G01N1/4077, Y10S251/903
European ClassificationG01N1/10