CA2141711A1 - Apparatus for cleaning oil of hydraulic systems - Google Patents
Apparatus for cleaning oil of hydraulic systemsInfo
- Publication number
- CA2141711A1 CA2141711A1 CA002141711A CA2141711A CA2141711A1 CA 2141711 A1 CA2141711 A1 CA 2141711A1 CA 002141711 A CA002141711 A CA 002141711A CA 2141711 A CA2141711 A CA 2141711A CA 2141711 A1 CA2141711 A1 CA 2141711A1
- Authority
- CA
- Canada
- Prior art keywords
- oil
- vessel
- hydraulic
- control unit
- main line
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
- F15B21/04—Special measures taken in connection with the properties of the fluid
- F15B21/041—Removal or measurement of solid or liquid contamination, e.g. filtering
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
The proposed, according to the invention, apparatus for cle-aning oils of hydraulic systems comprises the following elements hydraulically connected with the hydraulic system: inlet and out-let main lines connected by means of hydraulic pipelines with a vessel for waste oil, a separator having a pump and a secondary oil filter, a vessel for a cleaned oil, and an apparatus having an oil flowmeter internally accommodated in the outlet main line, and a control unit electrically connected with all the elements of the apparatus. The apparatus is provided with two delivery pumps, a first of which is disposed in the inlet main line ups-tream of the vessel for waste oil and a second delivery pump is disposed in the outlet main line between the vessel for cleaned oil and the oil flowmeter. Each vessel is provided with minimum and maximum oil level warning units electrically connected thro-ugh the control unit with the delivery pumps and with the pump of the separator. In addition the apparatus is provided with two hydraulic control valves a first of which is disposed between the first delivery pump and the vessel for waste oil and the second hydraulic control valve is disposed between the separator and the vessel for cleaned oil.
Description
Field of the Invention The present invention relates to means for complex servicing of hydraulic systems and more particularly to an apparatus for oil cleaning of hydraulic systems.
The present invention may be used for comple~: servicing of hydraulic systems and hydraulic equipment of casting machines~
automatic molding machines and machine~-tool equipment, presses, construction and road-building machines and transport facilities~
i.e. for cleaning their hyd~a-llic fluid from mechanical impuriti-es.
Background of the Invention The apparatuses for cleaning oil of the hydraulic systems known at the present time are designed for cleaning the hydraulic fluid of the hydraulic systems and are aimed at economy of this fluid~ as well as for minimi~ing wear of machine components cau-sed by contamination of the hydraulic fluid with mechanical impu-rities and for improving ecological conditions for their operati-on.
However~ operation of the known apparatuses is associated with operating modes of serviced hydraulie systems which makes it impossible to obtain a self-contained process for cleaning the hydraulic fluid and substantially reduces the output of these hydraulic systems.
~ nown in the prior art is an apparatus for cleaning oil of ` ~141711 hy~raulic systems (SU, ~ lBC169~) compricing inlet and outlet m~in lines hydraulically connected with a hydraulic system and interconnected by means of hydraulic pipelines incorporating a system of six hydraulic control valves with a vessel for waste oil~ a separ~tor having a pump and a secondary oil filter~ and a vessel for cleaned oil~ and the apparatus having an oil flowmeter tr~nsducer accommodated in the outlet main line and a control unit elec~rically connected with all the elements of the appara-tus.
Said appar~tus ha limited functional capabilities, as it is lacking ~elf-contained modes of rle~ning oil in the vessel for waste oil and in the vessel for cleaned oil. The presence ~f six hydraulic control valves impairs reliability of the apparatus and said hydraulic connections of the apparatus prevent the latter from performinr~ cleaning operations independently of the hydrau-lic system operation~
Summary of the Invention The principle objert the present invention is to provide such an apparatus which will allow the clPaninra of oil in hydrau-lic systems to be accQmplished independently of their operating modes.
It is another object of the present invention to provide a possibility of cle~ning oil of the hydraulic systems in a preset automati L mode~
Qne more object of the invention is to extend the functional 21~1711 capabilities of the apparatus for cleaning oil of hydraulic sys-tems.
These and other objects of the invention are attained in an appar-atus for cleaning oil of hydraulic systems comprising the followin~ elements hydraulically connected into the hydraulic system: inlet and outlet main lines connected by means of hydrau-lic pipelines having a first and a second hydraulic control val~
ves~ a vessel for waste oil~ a ~eparator having a secondary oil filter and a vessel for clean~d oil~ and the appar-atus incor-pora-ting an oil flowmeter transducer disposed in the outlet main li-ne, and a contr-ol unit electrically connected with all the ele-ments of the apparatus which~ according to the invention is pro-vided with two delivery pumps electrically connected with the control unit~ and the first delivery pump is installed upstream of the vessel for waste oil and the second delivery pump is ins-talled in the outlet main line between the vessel for cleaned oil and the oil flowmeter~ each vessel being provided with minimum and ma~,~imum oil level warning units electrically connected thro-u~h the control unit with the delivery pumps and a separator-pump~ the first hydraulic control valve being disposed in the hydraulic pipeline between the`first delivery pump and the vessel for waste oil and the second hydraulic ~ontrol valve being dispo-sed in the hydraulic pipeline between the separator and the ves-sel for cleaned oil.
The pres2nce of deliver-y pumps ma~es it possible to provide self--contained (independent~ operating modes of the apparatus proper and the serviced system. The hydr-aulic system may operate 5 ~
ir, operating modes required for its functionin~ while the appara-tus accomplishes the cleaning of oil to a requi~ed contamination class. Cleaning modes of the apparatus may be selected indepen-dently of the oil flow rate and pressure in the hydraulic system.
Two hydraulic control valves installed between the delivery pumps and the vessel~ allow the oil flow to be controlled depending upon the degree of filling the vesselsc The de~ree of filling the vessels i~ controlled by mean-- of minimum and ma~imum oil level wairning units installed in pairs in each vessel-which makes it pt~ssible to accomplish the oil ~leaning in a preset automatic mo-de.
If the degree o~ contamination o-f the oil to be cleaned is sufficiently high~ it is e::pedient that the apparatus be provided with a primary oil filter disposed in the outlet main line betwe-en the first delivery pump and ~he fir~t hydraulic control valve.
The presence of the primary oil filter p~ovides protection of the separator filter against an intensive contamination with mechani-cal particles ~nd insures a prolon~ed mode of oil cleaninq in the separator of the apparatus.
It is desira~l2 that the apparatus ~e provided with a bypass hydraulic pipeline the inl~t-of which is connecte~ with the fir~t hydraulic contrul valve and the outlet is connected with the out--let main line between the second delivery pump and the oil flow-meter.
The presence Qf a bypass hydraLllic pipeline makes it possib-le to keep on the oil cleanins proces~! when the vessel for waste oil ic filled up~ ~y mean~ of the primal;y oil filter and to deli-ver the cleaned oil in the hydraulic ~ystem bypassiny the mentio--ned vessel and the separato~ The given circuit allow~ the trans-fer arld filling of substantial volumes of oil in the as-received condition bypassin~ the sep~rator through the line: the first de-livery pump - the first hydraulic control. valve - the outlet main line~ which substantially extends the functional capabilities of the proposed apparatus.
It i 5 advantageous that the second hydraulic control valve be additionally hydraulically ~onnected with the vessel for waste oi~.
This makes it possible to provide a closed hydraulic circu-it. the vessel for waste oil - the separator - the second hydrau-lic control valve~ and to h:eep on the prolonged oil cleaning in this closed circuit brin~iny the contamination class to a requi-red level by way o-f repeatedly passing an isolated and limited volume of oil through the separator.
~ t is e~pedient that the second hydraulic control valve be additionally hydraulically connected with the outlet main line between the second delivery pump and the oil flowmeter~ This al-lows~ if required~ the delivery of a cleaned oil into the hydrau-lic system to be accomplished with the aid of the separator pump bypassin~ the ve~el for cleaned oil which e~,~tends the functional capabilities of the apparatus~
It is desirable that the apparatus be provided with an oil purity checkout unit ~nd the input thereof be hydraulically con-nected with the outlet main line betwe~n the second delivery pump and the oil flowmeter~ and the outlet of this unit be hydrauli-21~1711 cally connected with the hydraulic ~ystem. Introduction of theoil purity checkoLIt ~nit into the ~pparatus provide for an unin-terrupted .checkout of oil cleaning indicators in the outlet main line and for brinr~ing these indicators to the requirements laid down in the specifications for operation of the hydraulic system.
It i5 advantageous that the input of the oil purity checkout unit ~e hydraulically connected with the outlet main line through a hydraulic collector which i5 additlenally connected by one hyd-rRulic pipelinP with the inlet main line downstream of the first delivery pump and by arlather hydlraulic pipeline~ with the hydrau-lic sy~tem~ Such a connection ma~;es it possible to carry out the ch~ci.cut of the oil cleaning bot.h in the inlet and the outlet rra-in lines of the apparat-l~ and to ma~e a regular evaluation of the oil cleanin~ efficierlcy. ~onnection of the oil purity checkout unit inlet with the hydraulic system mak;es it possible to carry out the diagnostic mea~urements ~f th~ oil purity directly in the hydraulic system. It is preferred that. the oil purity checkout unit be provided with the followin~ element~ hydraulically cun-nected in ~erie~: an cil flowmeter transducer having an informa-tion output~ a mechanical pa~t.icle counter having a count initia-lizRtion element and a thruttling valve~ and also a controllable time~ the input of which i~ ~lectrically connected with the in-formation output of the oil flowmeter tran~ducer~ and the output of the controllable timer is electrically connected with the cn unt initiali2ation element of the mechanical particle counter.
Such a de~ign em~odiment of the ~il purity checkout unit provides for an adjustment of a required value of the oil flow thfough the mechanical particle counter~ as all the measurements tak:en in the prucess of oil cleaning are referred to a ~tandard specific unit of oii volume~ for e~ample 10~ ~m5~ ~nown standards N~S 16~B specify the ~uantity of me.hanical particles in oil exactly for ~uch vol~me. Cannection of the information output of the oil flowmeter tr-ansducer with the input of the controllable timer provides for a correc.tion of the time tak.en by the counting of mechanical particles in an oil flow depending upon variations in the oil flow passiny through the oil purity checkout unit.
It is likewise desirable that the oil purity ch~ckaut unit be pravided with a decoder havirlg a multidigit input and ~ one output~ and the mechanical particle counter be provided with multidicJit output electrically corlnected ~Jith the multidic~it in-put of the decoder the c~ne output af which be electrically con-nected with the cont:rol unit~
Such a cie~ign embocliment of the oil purity checkout unit ma-ke3 it possible ta a~tomatically identify the readings of the meehanical particle counter~ being essentially a multicJigit deci-mal number~ into ~ certain quality class~ namely a contamination class~ Thus the c~bjective character of the oil purity checkout is stepped up~ the wor~;ing c.onditiuns for an operator are improved and real condition~ are createcl fol- autom~tion of t.he oil clea-ning process starting from the (iiagncsing the cluality of oil in the hyciraulic syst.em~ m~inc~ up a required oi.l cleaning circuit in the apparatus and up tQ providincJ the deli~Jery of cleaned oil into the hyriraulic ~ystem.
Thu~ the use uf the propused appa~atus provides for manu-2i~1711 ., 9 _ facture of a highly efficient equipment for servicing hydraulicsystems in the process of their operation and automation of the oil drawing~ cleaning and delivery under the in-process control both of the manufacturing process and the provision of the pu~ity af the oil delivered by the proposed app13rat.us into the hydraulic sy~tem.
~ief De~c~iption of the Drawings The invention will now ~e described in greater detail with reference to a specific embodiment thereof~ taken in conjunction with the accompanying drawings~ wherein:
Fig.1 diagrammatically illustrates a left-side Yi ew of an apparatus for cleaning oil of hydraulic systems~ according to the invention~
Fig.~ - ditto~ a front view~
Fig.~ - ditto~ a right--side ~iew~
Fig.4 illustrates a hydr;3ulic circuit diagram of an appara-tus~ according to the invention~
Fig.5 illustrates a diagram of an oil purity checkout unit~
according to the invention~
Fig.~ illustrates a diagram of an appa~atus control unit~
according to the invention.
Description of the Freferred Embodiment ~ n apparat-ls~ according to the invention~ comprises a frame-- 10 ~
work 2 ~Fig.1) installed~ fo~ example~ on a tranCport carriage 1 and mounting a separator 3 (Fig ~)~ a first and a second delivery pumps 4~ 5 ~Fig.~)~ a vessel ~ ~Fig 1) for waste oil and a vessel 7 (Fig~) for cleaned oil ~ a first and a second hydraulic control valves 8~ ~ ~Fiq.1)~ an oil flowmeter 10 ~Fi~.~) and a control unit 11. For connectian to a hydr~ulic system ~n-ot shown in dra-wing) the apparatus is provided with unions 12~ 14 ~Fig.1) and 15 ~Fig.~).
~ n inlet main line 1~ tFig 4) internally accommodates in successinn the first delivery pump 4~ a primary oil filter 17~
~he first hydraulic control valve 8 the outlets thereof ~eing presented by a hydraulic pipeline læ connecting the first hydrau-lic control valve 8 with the vessel 6 for waste oil and by a by-pass hydraulic pipeline 1~ the inlet of whictt is connected with ~he first hydraulic control valve 8 and the outlet of which is connected with an outlet main-line ~0 between the second delivery pump 5 and the oil flowmeter ~0.
The ~ypa~s hydraulic pipeline 19 connecting the second out-let of the first hydraulic control valve 8 with the outlet main line 20 m~kes it possible to keep orl the oil cleaning process and the delivery of oil into the hydraulic system when the vessel 6 for waste oil i filled Llp th~ough the medium of the first deli-very pump 4~ The primary oil filter 17 protects the separator against an intensive contamination with mechanical particles if the degree of an initial contamination of the oil under cleaning is sufficiently high~
The vessels 6 and 7 are provided with minimum oil level war-nin8 units 2~ and ~ and ma~imum oil level warning units 24 and2S and are connected with the separator ~ by the second hydraulic control valve ~ and the econd delivery pump S throuQh ~he medium of hydraulic pipelines ~6~ ~7~ ~8, ~8 and ~0.
The second hydraulic control valve 9 is disposed in the hyd-raulic pipelines ~7 and ~8 between the separator ~ having a pump ~1 and a secorldary oil filtPr ~2~ and the vessel 7 for cleaned oil and i5 connected by means of a hydraulic pipeline ~ with the vessel 6 for waste oil aod by means ~f a hydraulic pipeline ~4~
with the outlet main line ~0 between the second delivery pump 5 and the oil flowmeter 1~1~
Connection of the second hydraulic control valve ~ with the outlet of the vessel ~ for waste oil ma~es it possible to keep on the prolon~eci cleaning of oil in the cloc.ed circ~lit: the separa-to~ 3 - the second hydr~ulic control valve q - the vessel 6 for waste oil anci t~ bring the degree of the oil purity to a required level. Connection of the second hydraulic control valve ~ with the o~tlet main line ~C~ ma~.es it possible t~ return the cleaned oil into the hydraulic ~yst.em by means of the pump 31 of the se-parator ~ without cutting t.he second delivery pump 5 into opera--tion~
The apparatus comprises an oil purity checkout unit ~5 the inlet of whi.ch i~ connected through the medium of a hydraulic pi-peline ~ with the outlet main line ~C~ between the second delive-ry pump 5 and the oil flowmeter 1~ and the outlet of which is hydraulically connected with the hydraulic systems through the union 15.
- ~141711 The fact that the apparatus is pro~ided with the oil purity checkout unit ~5 the input of which is hydraulically connected with the outlet main line ~0 and the outlet of which is connected with the hydraulic syst~m makes the oil rleaning process comple-tely controllable and objective This allows the apparatus opera-ting modes to be combined in the most optimal way depending upon a contamination class of the oil obtained at the apparatus out-let The input of the oil purity checkout unit ~5 ~Fig.5~ may be provided with a hydraulic collector ~7 a first inlet of which~ as wa~ mentioned hereinbefore~ i5 hydraulically connected with the outlet main line ~0 and a second input is additionally connected through the medium of a hydraulic pipeline 38 ~Fig.4) with the inlet main line 16 downstream of the first delivery pump 4 and through the medium of a pal-allel hydraulic pipeline ~ is connec-ted directly with the hydraulic pipeline through the inlet union 1~ .
~ n additional connection of the oil purity checkout unit ~5 through the hydraulic collector ~7 with the inlet main line 16 allows the purity of oil to be checked at the inlet of the appa-ratus. Thus~ with the accomplishment of the total control of the oil purity all pos~ible modes of oil cleaning are ~eali~ed by me-ans of the control unit 11 with the aim of attaining a required contamination class of oil.
Connection of the inlet of the oil purity checkout unit ~5 makes it possible to provide a diagnostic circuit for checking the putity of oil when only the oil purity checkout unit ~5 is 21~1711 ronnected to the hydraulic system and therefore depending upon contamination of oil in the hydraulic sy~tem the apparatus proper is cut at a required moment into operation. Thereafter the oil i5 delivered to the input of the oil pui--ity checkout unit 35 from th~ inlet main line 16 downstream of the first delivery pump 4~
The oil purity checkout unit ~5 ~Fig.5) comprises the following el~ments connecteci in series an¦oil flow transducer 40 including an information outp~At 41~ ~ mechanical particle counter 42 having a count initiali~ation element 4~ a~d a throttling valve 44~ a controllable timer 45 an input of which 4h is electrically con-nected with the information output 41 of the oil flow met~r transducer 40 and the output. of the rontrollable timer 45 is electrically connected with the COL~nt initiali~ation element 4 of the mechanical particle counter 4~.
For normal operation uf the mechanical particle counter 4 one condition should be met: a strictly constant flow rate of oil should be passed throu~h the c:ounter 4~. hccording to the norms of`standarcis N~S lh~ thi.s flow rate should be equal to 100 cm5.
Therefore the oil purity checkDut unit ~5 compri~es the oil flow meter transducer 4Cls t.he counter 4~ proper ~nd the throttling valve 44 which are connected ln series. The throttling valve 44 is desi~ned for settinc3 a rec~ ireJ flow rate of oil in the system of the oil purity checkout unit ~5. The value of the oil flow ra-te i~ checi~ed by readings of the oil flowmeter tiansdLIcer 40. The unlt ~5 is also provideJ with the controlla~le timei- 45 which me-asLlres a time interval i~etween the ~tarting and stopping of the count of mechaniral particles i.n the oil flow. This time is pre--~ 14 -~
liminar-ily scaled by readings of the oil flowmeter tr-ansducer 40 and subsequently in case of variations in the flow rate of oil passing through the mechanical particle counter 42 due to fluctu-ation of the tempe~atLIre and viscosity of oil i5 automatically regulated! therehy prcviding the passing of a strictly fixed vo-lurne of oil (lOC~ cm~) throLsgh the counter 4~
The mechanical particle counter- ~5 i5 also provided with decode~ 47 having a multidigit input 48 and a one output 4~, and the mechanical particle counter 42 also has a multidigit output 50 electrically connected with the multidigit input 48 of the de-coder 47 the one output 4~ of which is electrically connected with the contr-ol unit ll~
~ s the mechanical particle cuunter 4~ usually counts partic-les ~y gradations of particle si~es ~for example~ by six gradati-ons)~ then the re~ult of ~ountir1~ in a digital form looks rather awkward ~a thirty-digit number)~ The apparatus~ ac~ording to the invention~ i5 provided with a unique feature allowing automatic conversion o4 this number into a two-digit number corresponding to contamination class of oil according to standards N~S 16~8. It is e~actly this num~er i5 fed from the one output 49 of the deco-der 47 into the control unit ll Due to this~ it ~ecomes possible to conduct the process of oil cleaning and to program the modes of the control unit ll in the units o~ oil contamination class.
To provide the direction of ail flow the main lines ~Fig.4) ~ ~4~ and 19 are equipped with check valves 51~ 5~, 5~
and 54~ In addi t.i on ~ the apparatus is provided with pressure transducers 55~ 5~ 57 and 58 (Fig 5~ and temperature transducers si - 2l~l7ll -5~ ~Fig~4)~ hC) and 61 ~Fig~5~ connected with the control unit 11 ~Fig~6).
The control unit 11 comprises~ rO~ e~:ample~ a discre--te-ta--d}~ital converter 62~ a programmable logic array ~3 and a di yi tal--to-discrete converter 64 interconnected by an address bus 65 and a data bus ~6 of the proyrammable logic array 6~. The di~crete-to-digital converter 62 of the control unit 11 has a plurality of inputs presented by signal lines from the pressure tran~ducers 55~ 56~ 57~ 5B of the oil level warning units ~2~
24~ ~5 of the vessels 6~ 7~ from the decoder 47 of the oil purity checkoLIt unit ~5 and mode--of-operation selection channels 67 of the apparatL(s. The digital to discrete conve~ter 64 of the cont-~ol unit 11 has a plurality of outputs connected by corltrol lines of the pumps 4~ 5~ the hyd~auli.c control valves 8~ 9 and th hydraulic collector- ~7.
All the known elements of t.he apparatus for cleaning oil of hydraulic systems are standard and therefore any elements suitab-le for similar purposes may be used in the apparatus.
The apparatus fo~- cleaning oil of hydraulic systems operates in the following manner~
The oil is drawn 4rom~the e~ternal hydraulic system of as-semblies during their servicing throuyh the inlet unions 1~ and 1~ of the appar atus. E~y means of the pump 4 the hydraulic fluid is transferred from thP uni on 1~ throu~h the f i l te~ 17 and the hydraulic ~ontrol valve ~ and further flows throuQh the bypass line 1~ to the oil flowmeter 10 and to the outlet union 14~ If the external hydraulic sy~tem has a pressure differential the 21~171i ._ hy~raulic fluid i5 delivered through the uninn l~ and further by-passing the pump 4 is transferred to the oil cleaning devices ~the filter 17~ the separatur ~. In the su~sequent text the met-hod of drawing oil fr-om hydraulic systems is not specified, as for the functions of cleaning and delivery of the hydraulic flLIid both method~ uf oil drawing are eguivalent.
The cleaning of oil may be accompli~hed ~y means of two de-vices incorporated in the apparatusi the filter 17 and the sepa-ra~.or ~. Oil pa~ses through the filter 17 in all modes of the ap-paratus operation. The degree of oil cleaning from water and mec-hanical impurities i5 increased when oil passes through the fil-ter 17 of the separator ~. ~efore starting the separator ~ the flow of oil frum the hydraulic control valve 8 i 5 directed thro-ugh the hydraulic pipeline 18 into the vessel 6 for waste oil.
When the vessel 6 is filled up the separato~ ~ i 5 cut into opera-tion and the volume of c)i.l filling the vessel is subjected to a repeated filtration in the process of which the oil is drawn thrQugh the pipeline ~6 ~nd i 5 returned from the separator 3 through the hydrauli- -ontrol valve 9 and the pipeline ~3 into the vessel 6. At this time the drawing of oil from the system i5 ~topped by way of setting the-hydraulic control valve 8 in the neutral position~ or the oil i5 directly pumped through the hyd-raulic control valve 8 and the main line 19 to the union 14. Up~n the repeated cleaning in the circuit the vessel ~ - the separa-tor ~ the flow of oil i~. 5Wi tched over for filling the vessel 7 for cleaned oil thrcugh the hydraulic control valve 9. Thus~ the ve~sel for waste oil is once again prepared for filling it with 21~1711 . .
waste oil and a re Prve of the cleaned oil is provided in the ves~el 7 for its subsequent delivery into the hydraulic system.
Provision has been made for a diroct delivery af the cleaned oil from the vessel 6 of the sepa~ator ~ thr-ough the hydraulic control valve ~ anct the hydraulic pipeline 34 to the outlet main line 20.
The cleaned oil is delivered thro~gh the union 14 by one of the following methods - ~y the pump 4 th~o~igh the filter 175 the hydraulic cor~tr-ol valve 8 and the bypass line lq tc the oil flowmeter 10~
- by thP pump ~1 of the separator ~ from the vessel 6 thro-u9h the hydr-aulic cnntrol valve ~ the hydraulic pipeline 34 and further through the oil flowmeter 10~
- by the pump 5 from the vessel 7 through the hydraulic pi-peline ~f.), the outlet main line 2~ and the oil flowmeter 1-.) to the outlet union 14.
When the apparatus i~ in operation the hydra~lic system ele-ments function in the following manner.
The vessel ~ is filled ~ith waste oil by the pump 4 which delivers it from the union 12 through the filter 17 and further through the hy~raulic control valve 8 and ~he hydraulic pipeline ~ fter the ves~el 6 has been filled up the drawing of oil from the hydraulic system is stopped, the separator ~ is cut into ope-ration and draws oil from the vessel ~ through the hydraulic pi-peline ~h and directs it through the hydraulic control valve 9 and the hydrauli~ pipeline ~8 into the vessel 7 for cleaned oil~
Upon completion of the cleaning and transfer of oil from the ves-21~1711 sel 6 into the vessPl ~ the pump 5 is CUt into operation and ef-fects the deli~ery of the cleaned oil from the vessel 7 through the hydraulic pipeline ~C1 and the oil flowmeter 14 to the union 14~ ~t this time the cycle of filling the vessel 6 by the pump 4 is ~epeated~ In this pulse mode the complete and qualitative cle-aning of oil is effected in the hydraulic system being se~viced.
The combination of the oil cleaning cycle components i5 se-lected with the aid of the a~tomatic devices of the control unit 11 depending upon the readings of the oil purity checkout unit ~5.
The oil purity chec~:uut unit operates in the following man-ner.
In the line: the hydraulic collector ~7 - the oil flowmeter transducer 40 - the oil flowmeter 10 - the mechani~al particle countel- 42 the flow rate of oil is preliminarily set up by means of the throttling valve 44 within the limits of 100+30 cm5/min, as according to standards N~S 1~8 the quar)tity of mechanical particles being counted shall be referred to 100 cm~ of the hyd-raulic fluid. Further in the process of the checkout the code signal from the output 41 of the transducer 44 proportionai to the ~alue of the flow rate o~ oil passing through the counter 4,`
i~ fed into the inout of the timer 45 controlled t~y this code~ If the flow r-ate of oil is equal to 1~0 cm~min5 then a time inte~
val equal to 1 minute is applied to the count initialization ele-ment 4~ of the mechanical particle cuunter 42 during which the particles in the flow of oil passing through the counter 4~ ale counted in si~ si.e grol.(p~ micron: 5-lC)5 10-255 25-505 50-1045 21~1711 -lC~C)-2f)~)~ and over ~?C~C!. On the commar1ci rer.eived from the timer 45 the count of the parti c 1 e~ i S 5tarted artd ~itopped si mul taneou~l y in all t e si~e groups~ and thereafter the oil is classified for correspondence with the ~tanl:iards N~S 16~;8 by the readings of the counter 4:~. If in the process of the apparatils operation the va--1 ue of the f 1 ow rate of o:i I p~ssi ng t:hrough the counter 4~ beeo-mes less than 1~1C1 c:M~/min~ then ~ihe timeir 45 automatically e~:-tend~ the operating tim of the counter 4~ which togethei- with the test sampling yuaranteera the prAssing of the required amoul-tt of oi 1 equal to lOO c..m~SD When the f 1 ow ~-at.e of oi 1 i s over lC)C~
~M~min the time of cc:1uni.incl ti-he mechanical particles is respec--ti vel y reduced . Wi th the ai d of hydraul i c col l ector .~7 the oi l purity checkout unit ;;5 is connected to the inlet main line 16 or.
to the outlet main line 2C~. For automation of the oil cleaning process the countE?r 42 by a di CJi tal output 5~ thereof i s connec-~ted with the decocler 4B~ The latter operat:ing in an uninterruptecJ
rnocle identifies the rea~.iings of the ( ounter 4~ and delivers the command throu~h the co"trc:l channel to t:he input of the control ~Anit for changing the m~o(ie of operat ior\ or stopping the eleaning of oil when a required eor,tamination cla~s of oil is attained. In al 1 the cases the appe.rat~As i s connected to the hydraul i c ~ystem uncl~r servicing through the channels 12~ ; and 14, lS. Depending upon a selected scheme a req~.lired logi~ of operation is introdu-ced into tl:e control unit ll through the mode-of-operation selec-tion channels ~7~ The operating program of the control unit ll is pr~liminari1y introduceLi into the pro~rammable 1ogic array 6~..
Thereafter~ for each state of inputs of the discrete-to-digital 21~1711 corlverter 62 there i 5 a preset state of the outputs of the digi-tal-to-cdiscrete convertt?r 64.
~ 11 the hydraulic control valvPs and electric motors of dri-ves (not shown in the drawing~ of the pumps are tightly coupled by the mutual loyic of operation which provides wide functional capa~ilities of the apparatus.
The use of effective automation means made it possible to minimize the volumes of the apparatus own vessels which substan-tially increaseci the ef~ectiveness of oil cleanin~.
The mode of operation of the appar~tus is comhined depending upon the result~ of checkirlg the purity of hydraulic fluid. lt is exactly the break between the required and actually avail~ble ~ontaminatiun classes of oil that determines the rate of oil cle--aning~ the rate of ~llttiny the sepal-ator ~ into nperation and th~
rate of delivery of the cleaned oil. The prt?sence of the pumps 4 and S in the apparatus substantially e~tend~ the functional capa-~ilities thereof, as the use of only the separator in the moties of oil drawing and delivery i5 not rational f~om the technical standpoint~ anti in the majority of cases when the hydraLllic sys-tEm and the apparatus are dispused at different levels and at sul~tantial distarire from each other ~uch a u5e cannot be practi--cally realized.
Thus the propo~eti apparatus for ~leanin~ oil of hydrauli~
systems~ as well as the introduction of the oil purity checkout ur,it intG the apparatu~ as a cnmponent part thereof and th~
structure and couplinss of the control unit and the oil purity chec~;out unit provide the manufacture of the highly efficient ~1~1711 equipment for servicing hydra-llic systems and automation of the process of drawing~ cleaning and delivery of oil to a6semblies unde~ servicing along witll the in-p~ocess c~ntrol of the oil cle-aning and t.he purity of oil.
The use of the proposed apparatus substantially cuts down the cost of maintenance and repair~ as well as increases the ef-ficiency 01F cleanina the hydraulic fluid. The downtime of themachinery unde~ servicin~ is reduced ~practically is completely eliminated). The hyci~aul.ic circuit oJ the apparatu~ allows the me.chinery to be se~viced without stopping the hydraulic system which e~:tends the op~rating time and yields a sL~pplementary pro-fit.
The apparatus mak.es it possible to improve the qual ity of servicing hydraulic system~ which r~duce~ the number of repairs~
cuts down the consump~.ion of oi 1 at the e~.pense of incrPasing the cycle of its acti~e use without ~~epl~cing the oil by the indica-tors of i ts cor-tami r at. i c~n .
~ utomation of tl~e oiI c:leaning c.~cle ~ubstantially simpli~i-~s the appal-~tus upl~eep. Inc ease in t:he ser .ice life c~f o,1 imp-roves tt~e ecological situ~tiorl at the e~per se of dec~ease in the vclumes of drained waste oils~
The present invention may be used for comple~: servicing of hydraulic systems and hydraulic equipment of casting machines~
automatic molding machines and machine~-tool equipment, presses, construction and road-building machines and transport facilities~
i.e. for cleaning their hyd~a-llic fluid from mechanical impuriti-es.
Background of the Invention The apparatuses for cleaning oil of the hydraulic systems known at the present time are designed for cleaning the hydraulic fluid of the hydraulic systems and are aimed at economy of this fluid~ as well as for minimi~ing wear of machine components cau-sed by contamination of the hydraulic fluid with mechanical impu-rities and for improving ecological conditions for their operati-on.
However~ operation of the known apparatuses is associated with operating modes of serviced hydraulie systems which makes it impossible to obtain a self-contained process for cleaning the hydraulic fluid and substantially reduces the output of these hydraulic systems.
~ nown in the prior art is an apparatus for cleaning oil of ` ~141711 hy~raulic systems (SU, ~ lBC169~) compricing inlet and outlet m~in lines hydraulically connected with a hydraulic system and interconnected by means of hydraulic pipelines incorporating a system of six hydraulic control valves with a vessel for waste oil~ a separ~tor having a pump and a secondary oil filter~ and a vessel for cleaned oil~ and the apparatus having an oil flowmeter tr~nsducer accommodated in the outlet main line and a control unit elec~rically connected with all the elements of the appara-tus.
Said appar~tus ha limited functional capabilities, as it is lacking ~elf-contained modes of rle~ning oil in the vessel for waste oil and in the vessel for cleaned oil. The presence ~f six hydraulic control valves impairs reliability of the apparatus and said hydraulic connections of the apparatus prevent the latter from performinr~ cleaning operations independently of the hydrau-lic system operation~
Summary of the Invention The principle objert the present invention is to provide such an apparatus which will allow the clPaninra of oil in hydrau-lic systems to be accQmplished independently of their operating modes.
It is another object of the present invention to provide a possibility of cle~ning oil of the hydraulic systems in a preset automati L mode~
Qne more object of the invention is to extend the functional 21~1711 capabilities of the apparatus for cleaning oil of hydraulic sys-tems.
These and other objects of the invention are attained in an appar-atus for cleaning oil of hydraulic systems comprising the followin~ elements hydraulically connected into the hydraulic system: inlet and outlet main lines connected by means of hydrau-lic pipelines having a first and a second hydraulic control val~
ves~ a vessel for waste oil~ a ~eparator having a secondary oil filter and a vessel for clean~d oil~ and the appar-atus incor-pora-ting an oil flowmeter transducer disposed in the outlet main li-ne, and a contr-ol unit electrically connected with all the ele-ments of the apparatus which~ according to the invention is pro-vided with two delivery pumps electrically connected with the control unit~ and the first delivery pump is installed upstream of the vessel for waste oil and the second delivery pump is ins-talled in the outlet main line between the vessel for cleaned oil and the oil flowmeter~ each vessel being provided with minimum and ma~,~imum oil level warning units electrically connected thro-u~h the control unit with the delivery pumps and a separator-pump~ the first hydraulic control valve being disposed in the hydraulic pipeline between the`first delivery pump and the vessel for waste oil and the second hydraulic ~ontrol valve being dispo-sed in the hydraulic pipeline between the separator and the ves-sel for cleaned oil.
The pres2nce of deliver-y pumps ma~es it possible to provide self--contained (independent~ operating modes of the apparatus proper and the serviced system. The hydr-aulic system may operate 5 ~
ir, operating modes required for its functionin~ while the appara-tus accomplishes the cleaning of oil to a requi~ed contamination class. Cleaning modes of the apparatus may be selected indepen-dently of the oil flow rate and pressure in the hydraulic system.
Two hydraulic control valves installed between the delivery pumps and the vessel~ allow the oil flow to be controlled depending upon the degree of filling the vesselsc The de~ree of filling the vessels i~ controlled by mean-- of minimum and ma~imum oil level wairning units installed in pairs in each vessel-which makes it pt~ssible to accomplish the oil ~leaning in a preset automatic mo-de.
If the degree o~ contamination o-f the oil to be cleaned is sufficiently high~ it is e::pedient that the apparatus be provided with a primary oil filter disposed in the outlet main line betwe-en the first delivery pump and ~he fir~t hydraulic control valve.
The presence of the primary oil filter p~ovides protection of the separator filter against an intensive contamination with mechani-cal particles ~nd insures a prolon~ed mode of oil cleaninq in the separator of the apparatus.
It is desira~l2 that the apparatus ~e provided with a bypass hydraulic pipeline the inl~t-of which is connecte~ with the fir~t hydraulic contrul valve and the outlet is connected with the out--let main line between the second delivery pump and the oil flow-meter.
The presence Qf a bypass hydraLllic pipeline makes it possib-le to keep on the oil cleanins proces~! when the vessel for waste oil ic filled up~ ~y mean~ of the primal;y oil filter and to deli-ver the cleaned oil in the hydraulic ~ystem bypassiny the mentio--ned vessel and the separato~ The given circuit allow~ the trans-fer arld filling of substantial volumes of oil in the as-received condition bypassin~ the sep~rator through the line: the first de-livery pump - the first hydraulic control. valve - the outlet main line~ which substantially extends the functional capabilities of the proposed apparatus.
It i 5 advantageous that the second hydraulic control valve be additionally hydraulically ~onnected with the vessel for waste oi~.
This makes it possible to provide a closed hydraulic circu-it. the vessel for waste oil - the separator - the second hydrau-lic control valve~ and to h:eep on the prolonged oil cleaning in this closed circuit brin~iny the contamination class to a requi-red level by way o-f repeatedly passing an isolated and limited volume of oil through the separator.
~ t is e~pedient that the second hydraulic control valve be additionally hydraulically connected with the outlet main line between the second delivery pump and the oil flowmeter~ This al-lows~ if required~ the delivery of a cleaned oil into the hydrau-lic system to be accomplished with the aid of the separator pump bypassin~ the ve~el for cleaned oil which e~,~tends the functional capabilities of the apparatus~
It is desirable that the apparatus be provided with an oil purity checkout unit ~nd the input thereof be hydraulically con-nected with the outlet main line betwe~n the second delivery pump and the oil flowmeter~ and the outlet of this unit be hydrauli-21~1711 cally connected with the hydraulic ~ystem. Introduction of theoil purity checkoLIt ~nit into the ~pparatus provide for an unin-terrupted .checkout of oil cleaning indicators in the outlet main line and for brinr~ing these indicators to the requirements laid down in the specifications for operation of the hydraulic system.
It i5 advantageous that the input of the oil purity checkout unit ~e hydraulically connected with the outlet main line through a hydraulic collector which i5 additlenally connected by one hyd-rRulic pipelinP with the inlet main line downstream of the first delivery pump and by arlather hydlraulic pipeline~ with the hydrau-lic sy~tem~ Such a connection ma~;es it possible to carry out the ch~ci.cut of the oil cleaning bot.h in the inlet and the outlet rra-in lines of the apparat-l~ and to ma~e a regular evaluation of the oil cleanin~ efficierlcy. ~onnection of the oil purity checkout unit inlet with the hydraulic system mak;es it possible to carry out the diagnostic mea~urements ~f th~ oil purity directly in the hydraulic system. It is preferred that. the oil purity checkout unit be provided with the followin~ element~ hydraulically cun-nected in ~erie~: an cil flowmeter transducer having an informa-tion output~ a mechanical pa~t.icle counter having a count initia-lizRtion element and a thruttling valve~ and also a controllable time~ the input of which i~ ~lectrically connected with the in-formation output of the oil flowmeter tran~ducer~ and the output of the controllable timer is electrically connected with the cn unt initiali2ation element of the mechanical particle counter.
Such a de~ign em~odiment of the ~il purity checkout unit provides for an adjustment of a required value of the oil flow thfough the mechanical particle counter~ as all the measurements tak:en in the prucess of oil cleaning are referred to a ~tandard specific unit of oii volume~ for e~ample 10~ ~m5~ ~nown standards N~S 16~B specify the ~uantity of me.hanical particles in oil exactly for ~uch vol~me. Cannection of the information output of the oil flowmeter tr-ansducer with the input of the controllable timer provides for a correc.tion of the time tak.en by the counting of mechanical particles in an oil flow depending upon variations in the oil flow passiny through the oil purity checkout unit.
It is likewise desirable that the oil purity ch~ckaut unit be pravided with a decoder havirlg a multidigit input and ~ one output~ and the mechanical particle counter be provided with multidicJit output electrically corlnected ~Jith the multidic~it in-put of the decoder the c~ne output af which be electrically con-nected with the cont:rol unit~
Such a cie~ign embocliment of the oil purity checkout unit ma-ke3 it possible ta a~tomatically identify the readings of the meehanical particle counter~ being essentially a multicJigit deci-mal number~ into ~ certain quality class~ namely a contamination class~ Thus the c~bjective character of the oil purity checkout is stepped up~ the wor~;ing c.onditiuns for an operator are improved and real condition~ are createcl fol- autom~tion of t.he oil clea-ning process starting from the (iiagncsing the cluality of oil in the hyciraulic syst.em~ m~inc~ up a required oi.l cleaning circuit in the apparatus and up tQ providincJ the deli~Jery of cleaned oil into the hyriraulic ~ystem.
Thu~ the use uf the propused appa~atus provides for manu-2i~1711 ., 9 _ facture of a highly efficient equipment for servicing hydraulicsystems in the process of their operation and automation of the oil drawing~ cleaning and delivery under the in-process control both of the manufacturing process and the provision of the pu~ity af the oil delivered by the proposed app13rat.us into the hydraulic sy~tem.
~ief De~c~iption of the Drawings The invention will now ~e described in greater detail with reference to a specific embodiment thereof~ taken in conjunction with the accompanying drawings~ wherein:
Fig.1 diagrammatically illustrates a left-side Yi ew of an apparatus for cleaning oil of hydraulic systems~ according to the invention~
Fig.~ - ditto~ a front view~
Fig.~ - ditto~ a right--side ~iew~
Fig.4 illustrates a hydr;3ulic circuit diagram of an appara-tus~ according to the invention~
Fig.5 illustrates a diagram of an oil purity checkout unit~
according to the invention~
Fig.~ illustrates a diagram of an appa~atus control unit~
according to the invention.
Description of the Freferred Embodiment ~ n apparat-ls~ according to the invention~ comprises a frame-- 10 ~
work 2 ~Fig.1) installed~ fo~ example~ on a tranCport carriage 1 and mounting a separator 3 (Fig ~)~ a first and a second delivery pumps 4~ 5 ~Fig.~)~ a vessel ~ ~Fig 1) for waste oil and a vessel 7 (Fig~) for cleaned oil ~ a first and a second hydraulic control valves 8~ ~ ~Fiq.1)~ an oil flowmeter 10 ~Fi~.~) and a control unit 11. For connectian to a hydr~ulic system ~n-ot shown in dra-wing) the apparatus is provided with unions 12~ 14 ~Fig.1) and 15 ~Fig.~).
~ n inlet main line 1~ tFig 4) internally accommodates in successinn the first delivery pump 4~ a primary oil filter 17~
~he first hydraulic control valve 8 the outlets thereof ~eing presented by a hydraulic pipeline læ connecting the first hydrau-lic control valve 8 with the vessel 6 for waste oil and by a by-pass hydraulic pipeline 1~ the inlet of whictt is connected with ~he first hydraulic control valve 8 and the outlet of which is connected with an outlet main-line ~0 between the second delivery pump 5 and the oil flowmeter ~0.
The ~ypa~s hydraulic pipeline 19 connecting the second out-let of the first hydraulic control valve 8 with the outlet main line 20 m~kes it possible to keep orl the oil cleaning process and the delivery of oil into the hydraulic system when the vessel 6 for waste oil i filled Llp th~ough the medium of the first deli-very pump 4~ The primary oil filter 17 protects the separator against an intensive contamination with mechanical particles if the degree of an initial contamination of the oil under cleaning is sufficiently high~
The vessels 6 and 7 are provided with minimum oil level war-nin8 units 2~ and ~ and ma~imum oil level warning units 24 and2S and are connected with the separator ~ by the second hydraulic control valve ~ and the econd delivery pump S throuQh ~he medium of hydraulic pipelines ~6~ ~7~ ~8, ~8 and ~0.
The second hydraulic control valve 9 is disposed in the hyd-raulic pipelines ~7 and ~8 between the separator ~ having a pump ~1 and a secorldary oil filtPr ~2~ and the vessel 7 for cleaned oil and i5 connected by means of a hydraulic pipeline ~ with the vessel 6 for waste oil aod by means ~f a hydraulic pipeline ~4~
with the outlet main line ~0 between the second delivery pump 5 and the oil flowmeter 1~1~
Connection of the second hydraulic control valve ~ with the outlet of the vessel ~ for waste oil ma~es it possible to keep on the prolon~eci cleaning of oil in the cloc.ed circ~lit: the separa-to~ 3 - the second hydr~ulic control valve q - the vessel 6 for waste oil anci t~ bring the degree of the oil purity to a required level. Connection of the second hydraulic control valve ~ with the o~tlet main line ~C~ ma~.es it possible t~ return the cleaned oil into the hydraulic ~yst.em by means of the pump 31 of the se-parator ~ without cutting t.he second delivery pump 5 into opera--tion~
The apparatus comprises an oil purity checkout unit ~5 the inlet of whi.ch i~ connected through the medium of a hydraulic pi-peline ~ with the outlet main line ~C~ between the second delive-ry pump 5 and the oil flowmeter 1~ and the outlet of which is hydraulically connected with the hydraulic systems through the union 15.
- ~141711 The fact that the apparatus is pro~ided with the oil purity checkout unit ~5 the input of which is hydraulically connected with the outlet main line ~0 and the outlet of which is connected with the hydraulic syst~m makes the oil rleaning process comple-tely controllable and objective This allows the apparatus opera-ting modes to be combined in the most optimal way depending upon a contamination class of the oil obtained at the apparatus out-let The input of the oil purity checkout unit ~5 ~Fig.5~ may be provided with a hydraulic collector ~7 a first inlet of which~ as wa~ mentioned hereinbefore~ i5 hydraulically connected with the outlet main line ~0 and a second input is additionally connected through the medium of a hydraulic pipeline 38 ~Fig.4) with the inlet main line 16 downstream of the first delivery pump 4 and through the medium of a pal-allel hydraulic pipeline ~ is connec-ted directly with the hydraulic pipeline through the inlet union 1~ .
~ n additional connection of the oil purity checkout unit ~5 through the hydraulic collector ~7 with the inlet main line 16 allows the purity of oil to be checked at the inlet of the appa-ratus. Thus~ with the accomplishment of the total control of the oil purity all pos~ible modes of oil cleaning are ~eali~ed by me-ans of the control unit 11 with the aim of attaining a required contamination class of oil.
Connection of the inlet of the oil purity checkout unit ~5 makes it possible to provide a diagnostic circuit for checking the putity of oil when only the oil purity checkout unit ~5 is 21~1711 ronnected to the hydraulic system and therefore depending upon contamination of oil in the hydraulic sy~tem the apparatus proper is cut at a required moment into operation. Thereafter the oil i5 delivered to the input of the oil pui--ity checkout unit 35 from th~ inlet main line 16 downstream of the first delivery pump 4~
The oil purity checkout unit ~5 ~Fig.5) comprises the following el~ments connecteci in series an¦oil flow transducer 40 including an information outp~At 41~ ~ mechanical particle counter 42 having a count initiali~ation element 4~ a~d a throttling valve 44~ a controllable timer 45 an input of which 4h is electrically con-nected with the information output 41 of the oil flow met~r transducer 40 and the output. of the rontrollable timer 45 is electrically connected with the COL~nt initiali~ation element 4 of the mechanical particle counter 4~.
For normal operation uf the mechanical particle counter 4 one condition should be met: a strictly constant flow rate of oil should be passed throu~h the c:ounter 4~. hccording to the norms of`standarcis N~S lh~ thi.s flow rate should be equal to 100 cm5.
Therefore the oil purity checkDut unit ~5 compri~es the oil flow meter transducer 4Cls t.he counter 4~ proper ~nd the throttling valve 44 which are connected ln series. The throttling valve 44 is desi~ned for settinc3 a rec~ ireJ flow rate of oil in the system of the oil purity checkout unit ~5. The value of the oil flow ra-te i~ checi~ed by readings of the oil flowmeter tiansdLIcer 40. The unlt ~5 is also provideJ with the controlla~le timei- 45 which me-asLlres a time interval i~etween the ~tarting and stopping of the count of mechaniral particles i.n the oil flow. This time is pre--~ 14 -~
liminar-ily scaled by readings of the oil flowmeter tr-ansducer 40 and subsequently in case of variations in the flow rate of oil passing through the mechanical particle counter 42 due to fluctu-ation of the tempe~atLIre and viscosity of oil i5 automatically regulated! therehy prcviding the passing of a strictly fixed vo-lurne of oil (lOC~ cm~) throLsgh the counter 4~
The mechanical particle counter- ~5 i5 also provided with decode~ 47 having a multidigit input 48 and a one output 4~, and the mechanical particle counter 42 also has a multidigit output 50 electrically connected with the multidigit input 48 of the de-coder 47 the one output 4~ of which is electrically connected with the contr-ol unit ll~
~ s the mechanical particle cuunter 4~ usually counts partic-les ~y gradations of particle si~es ~for example~ by six gradati-ons)~ then the re~ult of ~ountir1~ in a digital form looks rather awkward ~a thirty-digit number)~ The apparatus~ ac~ording to the invention~ i5 provided with a unique feature allowing automatic conversion o4 this number into a two-digit number corresponding to contamination class of oil according to standards N~S 16~8. It is e~actly this num~er i5 fed from the one output 49 of the deco-der 47 into the control unit ll Due to this~ it ~ecomes possible to conduct the process of oil cleaning and to program the modes of the control unit ll in the units o~ oil contamination class.
To provide the direction of ail flow the main lines ~Fig.4) ~ ~4~ and 19 are equipped with check valves 51~ 5~, 5~
and 54~ In addi t.i on ~ the apparatus is provided with pressure transducers 55~ 5~ 57 and 58 (Fig 5~ and temperature transducers si - 2l~l7ll -5~ ~Fig~4)~ hC) and 61 ~Fig~5~ connected with the control unit 11 ~Fig~6).
The control unit 11 comprises~ rO~ e~:ample~ a discre--te-ta--d}~ital converter 62~ a programmable logic array ~3 and a di yi tal--to-discrete converter 64 interconnected by an address bus 65 and a data bus ~6 of the proyrammable logic array 6~. The di~crete-to-digital converter 62 of the control unit 11 has a plurality of inputs presented by signal lines from the pressure tran~ducers 55~ 56~ 57~ 5B of the oil level warning units ~2~
24~ ~5 of the vessels 6~ 7~ from the decoder 47 of the oil purity checkoLIt unit ~5 and mode--of-operation selection channels 67 of the apparatL(s. The digital to discrete conve~ter 64 of the cont-~ol unit 11 has a plurality of outputs connected by corltrol lines of the pumps 4~ 5~ the hyd~auli.c control valves 8~ 9 and th hydraulic collector- ~7.
All the known elements of t.he apparatus for cleaning oil of hydraulic systems are standard and therefore any elements suitab-le for similar purposes may be used in the apparatus.
The apparatus fo~- cleaning oil of hydraulic systems operates in the following manner~
The oil is drawn 4rom~the e~ternal hydraulic system of as-semblies during their servicing throuyh the inlet unions 1~ and 1~ of the appar atus. E~y means of the pump 4 the hydraulic fluid is transferred from thP uni on 1~ throu~h the f i l te~ 17 and the hydraulic ~ontrol valve ~ and further flows throuQh the bypass line 1~ to the oil flowmeter 10 and to the outlet union 14~ If the external hydraulic sy~tem has a pressure differential the 21~171i ._ hy~raulic fluid i5 delivered through the uninn l~ and further by-passing the pump 4 is transferred to the oil cleaning devices ~the filter 17~ the separatur ~. In the su~sequent text the met-hod of drawing oil fr-om hydraulic systems is not specified, as for the functions of cleaning and delivery of the hydraulic flLIid both method~ uf oil drawing are eguivalent.
The cleaning of oil may be accompli~hed ~y means of two de-vices incorporated in the apparatusi the filter 17 and the sepa-ra~.or ~. Oil pa~ses through the filter 17 in all modes of the ap-paratus operation. The degree of oil cleaning from water and mec-hanical impurities i5 increased when oil passes through the fil-ter 17 of the separator ~. ~efore starting the separator ~ the flow of oil frum the hydraulic control valve 8 i 5 directed thro-ugh the hydraulic pipeline 18 into the vessel 6 for waste oil.
When the vessel 6 is filled up the separato~ ~ i 5 cut into opera-tion and the volume of c)i.l filling the vessel is subjected to a repeated filtration in the process of which the oil is drawn thrQugh the pipeline ~6 ~nd i 5 returned from the separator 3 through the hydrauli- -ontrol valve 9 and the pipeline ~3 into the vessel 6. At this time the drawing of oil from the system i5 ~topped by way of setting the-hydraulic control valve 8 in the neutral position~ or the oil i5 directly pumped through the hyd-raulic control valve 8 and the main line 19 to the union 14. Up~n the repeated cleaning in the circuit the vessel ~ - the separa-tor ~ the flow of oil i~. 5Wi tched over for filling the vessel 7 for cleaned oil thrcugh the hydraulic control valve 9. Thus~ the ve~sel for waste oil is once again prepared for filling it with 21~1711 . .
waste oil and a re Prve of the cleaned oil is provided in the ves~el 7 for its subsequent delivery into the hydraulic system.
Provision has been made for a diroct delivery af the cleaned oil from the vessel 6 of the sepa~ator ~ thr-ough the hydraulic control valve ~ anct the hydraulic pipeline 34 to the outlet main line 20.
The cleaned oil is delivered thro~gh the union 14 by one of the following methods - ~y the pump 4 th~o~igh the filter 175 the hydraulic cor~tr-ol valve 8 and the bypass line lq tc the oil flowmeter 10~
- by thP pump ~1 of the separator ~ from the vessel 6 thro-u9h the hydr-aulic cnntrol valve ~ the hydraulic pipeline 34 and further through the oil flowmeter 10~
- by the pump 5 from the vessel 7 through the hydraulic pi-peline ~f.), the outlet main line 2~ and the oil flowmeter 1-.) to the outlet union 14.
When the apparatus i~ in operation the hydra~lic system ele-ments function in the following manner.
The vessel ~ is filled ~ith waste oil by the pump 4 which delivers it from the union 12 through the filter 17 and further through the hy~raulic control valve 8 and ~he hydraulic pipeline ~ fter the ves~el 6 has been filled up the drawing of oil from the hydraulic system is stopped, the separator ~ is cut into ope-ration and draws oil from the vessel ~ through the hydraulic pi-peline ~h and directs it through the hydraulic control valve 9 and the hydrauli~ pipeline ~8 into the vessel 7 for cleaned oil~
Upon completion of the cleaning and transfer of oil from the ves-21~1711 sel 6 into the vessPl ~ the pump 5 is CUt into operation and ef-fects the deli~ery of the cleaned oil from the vessel 7 through the hydraulic pipeline ~C1 and the oil flowmeter 14 to the union 14~ ~t this time the cycle of filling the vessel 6 by the pump 4 is ~epeated~ In this pulse mode the complete and qualitative cle-aning of oil is effected in the hydraulic system being se~viced.
The combination of the oil cleaning cycle components i5 se-lected with the aid of the a~tomatic devices of the control unit 11 depending upon the readings of the oil purity checkout unit ~5.
The oil purity chec~:uut unit operates in the following man-ner.
In the line: the hydraulic collector ~7 - the oil flowmeter transducer 40 - the oil flowmeter 10 - the mechani~al particle countel- 42 the flow rate of oil is preliminarily set up by means of the throttling valve 44 within the limits of 100+30 cm5/min, as according to standards N~S 1~8 the quar)tity of mechanical particles being counted shall be referred to 100 cm~ of the hyd-raulic fluid. Further in the process of the checkout the code signal from the output 41 of the transducer 44 proportionai to the ~alue of the flow rate o~ oil passing through the counter 4,`
i~ fed into the inout of the timer 45 controlled t~y this code~ If the flow r-ate of oil is equal to 1~0 cm~min5 then a time inte~
val equal to 1 minute is applied to the count initialization ele-ment 4~ of the mechanical particle cuunter 42 during which the particles in the flow of oil passing through the counter 4~ ale counted in si~ si.e grol.(p~ micron: 5-lC)5 10-255 25-505 50-1045 21~1711 -lC~C)-2f)~)~ and over ~?C~C!. On the commar1ci rer.eived from the timer 45 the count of the parti c 1 e~ i S 5tarted artd ~itopped si mul taneou~l y in all t e si~e groups~ and thereafter the oil is classified for correspondence with the ~tanl:iards N~S 16~;8 by the readings of the counter 4:~. If in the process of the apparatils operation the va--1 ue of the f 1 ow rate of o:i I p~ssi ng t:hrough the counter 4~ beeo-mes less than 1~1C1 c:M~/min~ then ~ihe timeir 45 automatically e~:-tend~ the operating tim of the counter 4~ which togethei- with the test sampling yuaranteera the prAssing of the required amoul-tt of oi 1 equal to lOO c..m~SD When the f 1 ow ~-at.e of oi 1 i s over lC)C~
~M~min the time of cc:1uni.incl ti-he mechanical particles is respec--ti vel y reduced . Wi th the ai d of hydraul i c col l ector .~7 the oi l purity checkout unit ;;5 is connected to the inlet main line 16 or.
to the outlet main line 2C~. For automation of the oil cleaning process the countE?r 42 by a di CJi tal output 5~ thereof i s connec-~ted with the decocler 4B~ The latter operat:ing in an uninterruptecJ
rnocle identifies the rea~.iings of the ( ounter 4~ and delivers the command throu~h the co"trc:l channel to t:he input of the control ~Anit for changing the m~o(ie of operat ior\ or stopping the eleaning of oil when a required eor,tamination cla~s of oil is attained. In al 1 the cases the appe.rat~As i s connected to the hydraul i c ~ystem uncl~r servicing through the channels 12~ ; and 14, lS. Depending upon a selected scheme a req~.lired logi~ of operation is introdu-ced into tl:e control unit ll through the mode-of-operation selec-tion channels ~7~ The operating program of the control unit ll is pr~liminari1y introduceLi into the pro~rammable 1ogic array 6~..
Thereafter~ for each state of inputs of the discrete-to-digital 21~1711 corlverter 62 there i 5 a preset state of the outputs of the digi-tal-to-cdiscrete convertt?r 64.
~ 11 the hydraulic control valvPs and electric motors of dri-ves (not shown in the drawing~ of the pumps are tightly coupled by the mutual loyic of operation which provides wide functional capa~ilities of the apparatus.
The use of effective automation means made it possible to minimize the volumes of the apparatus own vessels which substan-tially increaseci the ef~ectiveness of oil cleanin~.
The mode of operation of the appar~tus is comhined depending upon the result~ of checkirlg the purity of hydraulic fluid. lt is exactly the break between the required and actually avail~ble ~ontaminatiun classes of oil that determines the rate of oil cle--aning~ the rate of ~llttiny the sepal-ator ~ into nperation and th~
rate of delivery of the cleaned oil. The prt?sence of the pumps 4 and S in the apparatus substantially e~tend~ the functional capa-~ilities thereof, as the use of only the separator in the moties of oil drawing and delivery i5 not rational f~om the technical standpoint~ anti in the majority of cases when the hydraLllic sys-tEm and the apparatus are dispused at different levels and at sul~tantial distarire from each other ~uch a u5e cannot be practi--cally realized.
Thus the propo~eti apparatus for ~leanin~ oil of hydrauli~
systems~ as well as the introduction of the oil purity checkout ur,it intG the apparatu~ as a cnmponent part thereof and th~
structure and couplinss of the control unit and the oil purity chec~;out unit provide the manufacture of the highly efficient ~1~1711 equipment for servicing hydra-llic systems and automation of the process of drawing~ cleaning and delivery of oil to a6semblies unde~ servicing along witll the in-p~ocess c~ntrol of the oil cle-aning and t.he purity of oil.
The use of the proposed apparatus substantially cuts down the cost of maintenance and repair~ as well as increases the ef-ficiency 01F cleanina the hydraulic fluid. The downtime of themachinery unde~ servicin~ is reduced ~practically is completely eliminated). The hyci~aul.ic circuit oJ the apparatu~ allows the me.chinery to be se~viced without stopping the hydraulic system which e~:tends the op~rating time and yields a sL~pplementary pro-fit.
The apparatus mak.es it possible to improve the qual ity of servicing hydraulic system~ which r~duce~ the number of repairs~
cuts down the consump~.ion of oi 1 at the e~.pense of incrPasing the cycle of its acti~e use without ~~epl~cing the oil by the indica-tors of i ts cor-tami r at. i c~n .
~ utomation of tl~e oiI c:leaning c.~cle ~ubstantially simpli~i-~s the appal-~tus upl~eep. Inc ease in t:he ser .ice life c~f o,1 imp-roves tt~e ecological situ~tiorl at the e~per se of dec~ease in the vclumes of drained waste oils~
Claims (11)
1 An apparatus for oil cleaning in a hydraulic system, comprising - an inlet main line having a union for a hydraulic connec-tion with the hydraulic system;
- a first delivery pump installed in said inlet main line and including an electric drive;
- a first pressure transducer installed in said inlet main line downstream of said first delivery pump;
- a vessel for waste oil;
- a first minimurn oil level warning unit installed on said vessel for waste oil;
- a first maximum oil level warning unit installed on said vessel for waste oil;
- a first oil temperature transducer installed inside said vessel for waste oil;
- a first hydraulic pipeline hydraulically connecting said inlet main line with said vessel for waste oil;
- a first hydraulic control valve internally accommodated in said first hydraulic pipeline between said first delivery pump and said vessel for waste oil, and having an electric drive;
- a separator with an electrit drive and a secondary oil filter;
- a second pressure transducer installed between said pump and said filter of said separator;
- a second hydraulic pipeline connecting said vessel for waste oil with said separator;
- a vessel for cleaned oil;
- a second minimum oil level warning unit installed on said vessel for cleaned oil;
- a second maximum oil level warning unit installed on said vessel for cleaned oil;
- a second oil temperature transducer installed inside said vessel for cleaned oil;
- a third hydraulic pipeline connecting said separator with said vessel for cleaned oil;
- a second hydraulic control valve accommodated in said third hydraulic pipeline between said separator and said vessel for cleaned oil and including an electric drive;
an outlet main line comprising a union for a hydraulic connection with the hydraulic system;
- an oil flowmeter disposed in said outlet main line;
- a second delivery pump installed in said outlet main line between said vessel for cleaned oil and said oil flowmeter, and including an electric drive;
- a third pressure transducer installed in said outlet main line between the second delivery pump and said oil flowmeter;
- a control unit;
- a first input of said control unit electrically connected with said first minimum oil level warning unit of said vessel for waste oil;
- a second input of said control unit electrically connected with said first maximum oil level warning unit of said vessel for waste oil;
- a third input of said control unit electrically connected with said second minimum oil level warning unit of said vessel for cleaned oil;
- a fourth input of said control unit electrically connected with said second maximum oil level warning unit of said vessel for cleaned oil;
- a fifth input of said control unit electrically connected with said first pressure transducer ;
- a sixth input of said control unit electrically connected with said second pressure transducer;
- a seventh input of said control unit electrically connec-ted with said third pressure transducer;
- an eighth input of said control unit electrically connec-ted with said first oil temperature transducer;
- a ninth input of said control unit electrically connected with said second oil temperature transducer;
- a first output of said control unit electrically connected with said electric drive of said first delivery pump;
- a second output of said control unit electrically connect-ted with said electric drive of said pump of said separator;
- a third output of said control unit electrically connected with said electric drive of said second delivery pump;
- a fourth output of said control unit electrically connec-ted with said electric drive of said first hydraulic control val-ve;
- a fifth output of said control unit electrically connected with said electric drive of said second hydraulic control valve.
- a first delivery pump installed in said inlet main line and including an electric drive;
- a first pressure transducer installed in said inlet main line downstream of said first delivery pump;
- a vessel for waste oil;
- a first minimurn oil level warning unit installed on said vessel for waste oil;
- a first maximum oil level warning unit installed on said vessel for waste oil;
- a first oil temperature transducer installed inside said vessel for waste oil;
- a first hydraulic pipeline hydraulically connecting said inlet main line with said vessel for waste oil;
- a first hydraulic control valve internally accommodated in said first hydraulic pipeline between said first delivery pump and said vessel for waste oil, and having an electric drive;
- a separator with an electrit drive and a secondary oil filter;
- a second pressure transducer installed between said pump and said filter of said separator;
- a second hydraulic pipeline connecting said vessel for waste oil with said separator;
- a vessel for cleaned oil;
- a second minimum oil level warning unit installed on said vessel for cleaned oil;
- a second maximum oil level warning unit installed on said vessel for cleaned oil;
- a second oil temperature transducer installed inside said vessel for cleaned oil;
- a third hydraulic pipeline connecting said separator with said vessel for cleaned oil;
- a second hydraulic control valve accommodated in said third hydraulic pipeline between said separator and said vessel for cleaned oil and including an electric drive;
an outlet main line comprising a union for a hydraulic connection with the hydraulic system;
- an oil flowmeter disposed in said outlet main line;
- a second delivery pump installed in said outlet main line between said vessel for cleaned oil and said oil flowmeter, and including an electric drive;
- a third pressure transducer installed in said outlet main line between the second delivery pump and said oil flowmeter;
- a control unit;
- a first input of said control unit electrically connected with said first minimum oil level warning unit of said vessel for waste oil;
- a second input of said control unit electrically connected with said first maximum oil level warning unit of said vessel for waste oil;
- a third input of said control unit electrically connected with said second minimum oil level warning unit of said vessel for cleaned oil;
- a fourth input of said control unit electrically connected with said second maximum oil level warning unit of said vessel for cleaned oil;
- a fifth input of said control unit electrically connected with said first pressure transducer ;
- a sixth input of said control unit electrically connected with said second pressure transducer;
- a seventh input of said control unit electrically connec-ted with said third pressure transducer;
- an eighth input of said control unit electrically connec-ted with said first oil temperature transducer;
- a ninth input of said control unit electrically connected with said second oil temperature transducer;
- a first output of said control unit electrically connected with said electric drive of said first delivery pump;
- a second output of said control unit electrically connect-ted with said electric drive of said pump of said separator;
- a third output of said control unit electrically connected with said electric drive of said second delivery pump;
- a fourth output of said control unit electrically connec-ted with said electric drive of said first hydraulic control val-ve;
- a fifth output of said control unit electrically connected with said electric drive of said second hydraulic control valve.
2. An apparatus as set forth in claim 1 comprising a primary oil filter disposed in said inlet main line between said first delivery pump and said first hydraulic control valve.
3. An apparatus as set forth in claim 2 comprising a bypass hydraulic pipeline having its inlet connected with said first hydraulic control valve and having its outlet connected with said outlet main line between said second delivery pump and said oil flowmeter.
4. An apparatus as set forth in claim 1, wherein said second hydraulic control valve is additionally hydraulically connected with said vessel for waste oil.
5. An apparatus as set forth in claim 2, wherein said second hydraulic control valve is additionally hydraulically connected with said vessel for waste oil.
6. An apparatus as set forth in claim 4, wherein said second hydraulic control valve is additionally hydraulically connected with said outlet main line between said second delivery pump and said oil flowmeter.
7. An apparatus as set forth in claim 5, wherein said second hydraulic control valve is additionally hydraulically connected with said outlet main line between said second delivery pump and said oil flowmeter.
8. An apparatus as set forth in claim 1 comprising an oil purity checkout unit having its inlet hydraulically connected with said outlet main line between said second delivery pump and said oil flowmeter and having its outlet hydraulically connected with the hydraulic system.
9 . An apparatus as set forth in claim 8, wherein the input of said oil purity checkout unit is connected with said inlet ma-in line through an electrically driven hydraulic collector which is additionally connected by the fourth hydraulic pipeline with said inlet main line downstream of said first delivery pump, and connected by the fifth hydraulic pipeline with the hydraulic sys-tem, said control unit having its sixth output electrically con-nected with said drive of said hydraulic collector.
10. An apparatus as set forth in claim 9, wherein said oil purity checkout unit comprises the following elements hydrauli-cally connected in series: an oil flowmeter transducer having an information output, a mechanical particle counter having a count initialization element and a throttling valve, as well as a cont-rollable timer having its input electrically connected with said information output of said oil flowmeter transducer and having its output electrically connected with said count initialization element of said mechanical particle counter and said oil purity checkout unit has its fourth pressure transducer installed ups-tream of said oil flowmeter transducer and a third oil temperatu-re transducer installed upstream of said mechanical particle co-unter, and said control unit has its tenth input electrically connected with said fourth pressure transducer and has its ele-venth input electrically connected with said third oil temperatu-re transducer.
11. An apparatus as set forth in claim 10, wherein said oil purity checkout unit comprises a decoder having a multidigit in-put and a one output said mechanical particle counter has a mul-tidigit output eletrically connected with said multidigit input of said decoder; said control unit has its twelfth input electri-cally connected with said one output of said decoder.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| RU94004545 | 1994-02-08 | ||
| RU9494004545A RU2059901C1 (en) | 1994-02-08 | 1994-02-08 | Unit for sampling, cleaning and output of working fluid while sets are attended |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2141711A1 true CA2141711A1 (en) | 1995-08-09 |
Family
ID=20152299
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002141711A Abandoned CA2141711A1 (en) | 1994-02-08 | 1995-02-02 | Apparatus for cleaning oil of hydraulic systems |
Country Status (4)
| Country | Link |
|---|---|
| AU (1) | AU1593195A (en) |
| CA (1) | CA2141711A1 (en) |
| RU (1) | RU2059901C1 (en) |
| WO (1) | WO1995022005A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2596252A4 (en) * | 2010-07-20 | 2016-04-13 | Mera As | Method and device for treatment of liquid in a hydraulic system |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102226961B (en) * | 2011-04-01 | 2016-01-13 | 江苏省电力公司南京供电公司 | Transformer switch room live oil-replacing device and application process thereof |
| RU2554176C2 (en) * | 2013-10-24 | 2015-06-27 | Общество с ограниченной ответственностью "Технологии энергосбережения и экологии" | Device for cleaning of hydraulic system work liquid |
| RU2616733C1 (en) * | 2016-01-22 | 2017-04-18 | Общество с ограниченной ответственностью "НИЦ "Теас-МО" (ООО "НИЦ "Теас-МО") | Way of fluid optimal working purity maintaining in hydraulic systems and device for its implementation |
| RU2667850C1 (en) * | 2017-11-17 | 2018-09-24 | Общество с ограниченной ответственностью "Технологии энергосбережения и экологии" | Device for maintaining the optimum level of cleanliness of the working liquid in the hydraulic system |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DD127314B1 (en) * | 1976-08-03 | 1980-07-23 | Winfried Bautz | METHOD AND CIRCUIT ARRANGEMENT FOR OIL CHANGE IN HYDRAULIC SYSTEMS |
| GB1590985A (en) * | 1977-11-30 | 1981-06-10 | Bredon Hydraulics | Hydraulic power packs |
| DE2927971A1 (en) * | 1979-07-11 | 1981-01-29 | Fluidtech Gmbh | DEVICE FOR FILLING A HYDRAULIC SYSTEM, FOR FILTERING ITS PRESSURE AND FOR EMPTYING THIS SYSTEM |
| DE3625874A1 (en) * | 1986-07-31 | 1988-02-04 | Siemens Ag | DEVICE FOR CLEANING A LIQUID |
| US4846967A (en) * | 1986-09-24 | 1989-07-11 | Keller Machine Works | Apparatus for reclaiming contaminated oil |
| US5173180A (en) * | 1990-12-06 | 1992-12-22 | Gary Stewart | Domestic water conservation system |
| US5217607A (en) * | 1992-02-21 | 1993-06-08 | Diamond Water Systems, Inc. | Water decontamination system with filter, electrostatic treatment and UV radiation chamber |
-
1994
- 1994-02-08 RU RU9494004545A patent/RU2059901C1/en active
-
1995
- 1995-01-17 WO PCT/RU1995/000006 patent/WO1995022005A1/en active Application Filing
- 1995-01-17 AU AU15931/95A patent/AU1593195A/en not_active Abandoned
- 1995-02-02 CA CA002141711A patent/CA2141711A1/en not_active Abandoned
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2596252A4 (en) * | 2010-07-20 | 2016-04-13 | Mera As | Method and device for treatment of liquid in a hydraulic system |
Also Published As
| Publication number | Publication date |
|---|---|
| AU1593195A (en) | 1995-08-29 |
| RU2059901C1 (en) | 1996-05-10 |
| WO1995022005A1 (en) | 1995-08-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4121094A (en) | System for detecting, indicating and regulating the level of semi-solid matter in a reservoir | |
| US4616700A (en) | Automatic well test system and method | |
| CN1809656B (en) | Electrocoat management system | |
| DE29917651U1 (en) | Transmitter and process control system | |
| AU7750594A (en) | Apparatus for servicing automatic transmissions and the like | |
| GB2392258A (en) | Hydraulic circuit with a return line metering valve and method of operation | |
| CA2141711A1 (en) | Apparatus for cleaning oil of hydraulic systems | |
| US4341642A (en) | Process and an apparatus for continuously filtering liquids | |
| EP0781725B1 (en) | Multiple fluid dispensing system | |
| DE10230607A1 (en) | Method for monitoring a measuring device, in particular a flow measuring device, and a measuring device itself | |
| EP0895960B1 (en) | Process and device for dispensing liquid from a truck comprising multiple storage tanks | |
| EP0435985A4 (en) | A method of operating a plurality of minerals separation flotation cells | |
| EP0933111A3 (en) | Apparatus for distributing gas and liquid during concurrent gas/liquid backwash in filter underdrain flumes | |
| US6860142B2 (en) | Method and apparatus for measuring a variable in a lubricant/coolant system | |
| DE4229833C2 (en) | Pressure information processing device for use in a vacuum unit | |
| US5261437A (en) | Method and apparatus for monitoring and analyzing recirculation control system performance | |
| US6063269A (en) | Filtration apparatus for a hydraulic system | |
| US4690794A (en) | System for controlling driving water for control rod driving mechanism of nuclear reactor | |
| DE202006018620U1 (en) | Liquid e.g. water, level control device for use in e.g. cooling water tank, has signal input/output module, which is connected with liquid observation signal unit, and inner current unit, which is connected with current input/output module | |
| JPH02180667A (en) | Coating material circulating apparatus | |
| DE19521297C1 (en) | Container internal pressure regulation system | |
| CN210527456U (en) | Flow guiding device | |
| DE19701317A1 (en) | Leak recognition in fluid pipeline system | |
| EP0540984A2 (en) | Centralized change of parameters of hall and car equipment | |
| GB2149492A (en) | Cooling means for a hydraulic system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| FZDE | Discontinued |