WO2000071233A1 - Method for dewatering hydraulic fluids and device for carrying out said method - Google Patents
Method for dewatering hydraulic fluids and device for carrying out said method Download PDFInfo
- Publication number
- WO2000071233A1 WO2000071233A1 PCT/EP2000/003126 EP0003126W WO0071233A1 WO 2000071233 A1 WO2000071233 A1 WO 2000071233A1 EP 0003126 W EP0003126 W EP 0003126W WO 0071233 A1 WO0071233 A1 WO 0071233A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- membrane
- brake
- absorbent
- water
- hydraulic
- Prior art date
Links
- 239000012530 fluid Substances 0.000 title claims abstract description 46
- 238000000034 method Methods 0.000 title claims abstract description 15
- 239000012528 membrane Substances 0.000 claims abstract description 39
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 39
- 239000012466 permeate Substances 0.000 claims abstract description 5
- 238000005373 pervaporation Methods 0.000 claims abstract description 5
- 230000002745 absorbent Effects 0.000 claims description 18
- 239000002250 absorbent Substances 0.000 claims description 18
- 239000004952 Polyamide Substances 0.000 claims description 3
- 229920002647 polyamide Polymers 0.000 claims description 3
- 229920002943 EPDM rubber Polymers 0.000 claims description 2
- 239000000919 ceramic Substances 0.000 claims description 2
- 239000002131 composite material Substances 0.000 claims description 2
- 229920001577 copolymer Polymers 0.000 claims description 2
- HQQADJVZYDDRJT-UHFFFAOYSA-N ethene;prop-1-ene Chemical group C=C.CC=C HQQADJVZYDDRJT-UHFFFAOYSA-N 0.000 claims description 2
- 239000002861 polymer material Substances 0.000 claims 2
- 239000000463 material Substances 0.000 claims 1
- 238000010521 absorption reaction Methods 0.000 abstract description 5
- ODINCKMPIJJUCX-UHFFFAOYSA-N Calcium oxide Chemical compound [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 10
- 239000002274 desiccant Substances 0.000 description 8
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 6
- 239000000292 calcium oxide Substances 0.000 description 5
- 235000012255 calcium oxide Nutrition 0.000 description 5
- CPLXHLVBOLITMK-UHFFFAOYSA-N Magnesium oxide Chemical compound [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 4
- KGBXLFKZBHKPEV-UHFFFAOYSA-N boric acid Chemical compound OB(O)O KGBXLFKZBHKPEV-UHFFFAOYSA-N 0.000 description 4
- 239000004327 boric acid Substances 0.000 description 4
- 101100191138 Arabidopsis thaliana DOT4 gene Proteins 0.000 description 3
- 101100427348 Saccharomyces cerevisiae (strain ATCC 204508 / S288c) UBP10 gene Proteins 0.000 description 3
- 238000007791 dehumidification Methods 0.000 description 3
- 229920000151 polyglycol Polymers 0.000 description 3
- 239000010695 polyglycol Substances 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000009835 boiling Methods 0.000 description 2
- 238000009792 diffusion process Methods 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 239000000395 magnesium oxide Substances 0.000 description 2
- 229920000642 polymer Polymers 0.000 description 2
- 238000001179 sorption measurement Methods 0.000 description 2
- BTBUEUYNUDRHOZ-UHFFFAOYSA-N Borate Chemical compound [O-]B([O-])[O-] BTBUEUYNUDRHOZ-UHFFFAOYSA-N 0.000 description 1
- 239000004642 Polyimide Substances 0.000 description 1
- 230000000712 assembly Effects 0.000 description 1
- 238000000429 assembly Methods 0.000 description 1
- 230000000740 bleeding effect Effects 0.000 description 1
- 239000012876 carrier material Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 229920001971 elastomer Polymers 0.000 description 1
- 239000000806 elastomer Substances 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 230000002706 hydrostatic effect Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000009533 lab test Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 230000005923 long-lasting effect Effects 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 229920001721 polyimide Polymers 0.000 description 1
- 229920006254 polymer film Polymers 0.000 description 1
- 229920005597 polymer membrane Polymers 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000009423 ventilation Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
- B60T17/00—Component parts, details, or accessories of power brake systems not covered by groups B60T8/00, B60T13/00 or B60T15/00, or presenting other characteristic features
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
- B01D61/36—Pervaporation; Membrane distillation; Liquid permeation
- B01D61/362—Pervaporation
-
- 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
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D65/00—Parts or details
- F16D65/14—Actuating mechanisms for brakes; Means for initiating operation at a predetermined position
- F16D65/16—Actuating mechanisms for brakes; Means for initiating operation at a predetermined position arranged in or on the brake
- F16D65/18—Actuating mechanisms for brakes; Means for initiating operation at a predetermined position arranged in or on the brake adapted for drawing members together, e.g. for disc brakes
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D2121/00—Type of actuator operation force
- F16D2121/02—Fluid pressure
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D2125/00—Components of actuators
- F16D2125/02—Fluid-pressure mechanisms
- F16D2125/06—Pistons
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D2125/00—Components of actuators
- F16D2125/02—Fluid-pressure mechanisms
- F16D2125/16—Devices for bleeding or filling
Definitions
- the invention relates to a method for dewatering hydraulic fluids and a device for performing the method.
- Hydraulic fluids are used in hydraulic systems for both hydrostatic and hydrodynamic drives. Hydraulic systems are mainly used in control, regulating, drive and braking devices of vehicles, aircraft and other devices.
- Hydraulic systems are essential components, especially in automotive engineering.
- the brake fluid serves as a medium for power transmission and transmission in the. Vehicle assemblies clutch and brake.
- the pressure generated in the master brake cylinder is transmitted to the wheel brake cylinders by the brake fluid.
- the properties of the brake fluid are therefore of great importance for the function and the design.
- a brake fluid must meet a variety of different requirements, in particular:
- the properties of the brake fluids are determined by their chemical structure. A brake fluid that has all the properties at the same time is currently not available.
- the brake fluids used today are based in particular on polyglycol ether. These brake fluids have several of the required properties. However, it is disadvantageous that they are hygroscopic, which leads to water absorption by the brake fluid. This can be counteracted by adding boric acid. This creates borate testers from the polyglycols. At higher water concentrations, the boric acid ether splits into boric acid and polyglycol ether. This addition of boric acid creates brake fluids that are less sensitive to water (e.g. DOT-4 and higher).
- JP62203864 describes a method for the continuous dewatering of brake fluids, in which a polymer membrane is integrated in a brake hose. Due to the different molecular diameters, the membrane is only permeable to water, but not to the brake fluid. The way in which the water which has passed through the membrane is treated further on the permeate side to maintain a water vapor partial pressure drop is not described in any more detail in this literature reference.
- WO 9S / 48175 describes a method for dewatering hydraulic fluids by pervaporation using a Solution / diffusion membrane disclosed. In order to maintain a water vapor partial pressure difference, either an overpressure or an underpressure on the permeate side is built up within the hydraulic system.
- the object of the invention is to provide a method and a device for dewatering hydraulic fluids, in particular brake fluids, which enables dewatering in a reliable manner in a small space.
- a device for performing the method is the subject of claim 2.
- the water contained in the hydraulic fluid is separated from the hydraulic fluid according to the principle of pervaporation on a membrane which is permeable to water and impermeable to the hydraulic fluid.
- a driving force must be present so that the water can be transported through the membrane.
- a water vapor partial pressure drop between the two sides of the membrane serves as the driving force.
- an absorbent also called desiccant or absorbent below
- Absorption is the penetration of gases in liquids or solids. It is therefore a form of sorption.
- the surface plays a minor role in absorption. In general, absorption is associated with an increase in volume of the absorbent.
- the absorbent is even more hygroscopic than the hydraulic fluid itself.
- Particularly suitable are substances which form a chemical compound with water and in which the water can only be split off by firing at higher temperatures. These include, for example, CaO (quicklime) or MgO (magnesia).
- the absorbent can advantageously be arranged on an inert, porous carrier material. Once the absorbent is fully loaded with water, it must be replaced. When installed in the hydraulic system, the absorbent is advantageously positioned such that it can be replaced quickly and easily.
- the membranes there are special requirements for the membranes to be used, particularly with regard to their chemical, thermal and mechanical properties. For example, With brake hydraulics, temperatures up to 200 ° C and pressures up to 200 bar are common. It is therefore advantageous to use a composite membrane which comprises a porous, metallic support and optionally a ceramic intermediate layer and a dense polymer film which represents the actual separation layer (solution / diffusion membrane).
- the following polymers are used particularly advantageously for this separating layer:
- the invention can be used in particular in a bre system, especially in a motor vehicle.
- the membrane can be cylindrical, for example, and can be arranged in a hose-like line section of the brake system.
- the connecting line to the brake caliper is particularly suitable here, the membrane forming the end section of the line adjacent to the brake caliper.
- the membrane is in this Ser execution surrounded by the absorbent over its entire outer circumference.
- the membrane can also be flat.
- the membrane and absorbent can be arranged particularly advantageously in the bottom of a hydraulic piston within the brake system.
- the advantages of the invention are essentially that reliable and space-saving dewatering of the hydraulic fluid is achieved.
- the change intervals of the hydraulic fluid can be increased significantly.
- the function according to the invention is guaranteed at pressures up to at least 200 bar and at temperatures up to at least 200 ° C.
- the drainage is particularly independent of the atmospheric ambient conditions.
- the water content was 40 g of DOT4 + from 2.5% of water at 100 ° C. reduced to 0.5% water content in 83 hours. 0.8 g of water were removed.
- the device 3 according to the invention for dehumidifying the brake fluid is connected to the brake caliper 1 via a screw connection 4.
- the device 3 comprises a tubular membrane 5 in direct contact with the brake fluid.
- the membrane is surrounded by desiccant 6, which absorbs and binds the moisture transported through the membrane.
- a brake hose 7 for supplying pressure to the brake caliper 1 is connected via a screw connection 8.
- the brake caliper 1 is essentially identical to that shown in FIG. 1.
- the dehumidifying device according to the invention is not integrated in the brake hose 7, but instead is screwed directly onto the brake caliper as a separate structural unit (spoilage 13). It is in contact with the pressure chamber of the brake caliper 1.
- the dehumidifying device can be arranged particularly advantageously in the place of a ventilation screw, not shown here.
- the brake fluid loaded with moisture enters space 12, in which it can spread out in front of the flat membrane.
- the drying agent 10 which absorbs the moisture.
- the dehumidifying device does not lie in the flow through a hydraulic line. An exchange of the device in the manner of a cartridge is simplified. This exchange can be combined with bleeding the brake caliper.
- a brake caliper 14 is shown in a partial section.
- a brake piston 15 is arranged displaceably in a cylinder housing 16.
- the dehumidifying device according to the invention with membrane 19 and desiccant 20 is screwed onto the front side of the cylinder housing.
- the brake fluid in the pressure area behind the piston 15 can thus come into direct contact with the membrane 19 and release its moisture via the membrane 19 to the drying agent 20.
- This design thus allows dehumidification directly in the area of impending vapor bubble formation.
- the dehumidifier can be replaced easily and quickly in the position shown.
- FIG. 4 shows a further, particularly preferred embodiment of the invention.
- the piston 21 within the caliper 14 is designed such that the membrane 23 is integrated in the piston. Similar to Fig. 3, this embodiment allows dehumidification in the area of impending vapor bubble formation.
- the drying agent 22 is located in the space formed on the rear side of the membrane. With this embodiment of the invention, a relatively large volume of drying agent can be present directly in the wheel brake, so that a long-lasting dehumidification performance is achieved with correspondingly extended changing intervals.
Landscapes
- Engineering & Computer Science (AREA)
- Water Supply & Treatment (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Analytical Chemistry (AREA)
- Transportation (AREA)
- Braking Arrangements (AREA)
- Valves And Accessory Devices For Braking Systems (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
The invention relates to a method and device for dewatering hydraulic fluids within a hydraulic system, whereby water contained in the hydraulic fluid is separated out, according to the principle of pervaporation, from the same on a membrane (5, 11, 19, 23) which is permeable to water but impermeable to hydraulic fluid and in whose area a partial pressure gradient for water is maintained. According to the invention, the water that has been separated out is absorbed on the side of the permeate by an absorption means (6, 10, 20, 22) in order to maintain the water vapor partial pressure gradient.
Description
Beschreibung description
Verfahren zum Entwässern von Hydraulikflüssigkeiten sowie Vorrichtung zur Durchführung des Verfahrens.Process for dewatering hydraulic fluids and device for carrying out the process.
Die Erfindung betrifft ein Verfahren zum Entwässern von Hydraulikflüssigkeiten sowie eine Vorrichtung zur Durchführung des Verfahrens .The invention relates to a method for dewatering hydraulic fluids and a device for performing the method.
In Hydrauliksystemen sowohl zum hydrostatischen als auch zum hydrodynamischen Antrieb werden Hydraulikflüssigkeiten eingesetzt. Hydrauliksysteme werden vor allem in Steuer-, Regel-, Antriebs- und Bremsvorrichtungen von Fahrzeugen, Flugzeugen und anderen Geräten eingesetzt.Hydraulic fluids are used in hydraulic systems for both hydrostatic and hydrodynamic drives. Hydraulic systems are mainly used in control, regulating, drive and braking devices of vehicles, aircraft and other devices.
Speziell im Kraftfahrzeugbau sind Hydrauliksysteme wesentliche Komponenten. Die Bremsflüssigkeit dient als Medium der Kraftübertragung und -Übersetzung in der. Fahrzeugbaugruppen Kupplung und Bremse. Der im Hauptbremszylinder erzeugte Druck wird durch die Bremsflüssigkeit an die Radbremszyiinder übertragen. Für die Funktion und die Auslegung sind daher die Eigenschaften der Bremsflüssigkeit von großer Bedeutung. Eine Bremsflüssigkeit muß eine Vielzahl unterschiedlicher Anforderungen erfüllen, insbesondere:Hydraulic systems are essential components, especially in automotive engineering. The brake fluid serves as a medium for power transmission and transmission in the. Vehicle assemblies clutch and brake. The pressure generated in the master brake cylinder is transmitted to the wheel brake cylinders by the brake fluid. The properties of the brake fluid are therefore of great importance for the function and the design. A brake fluid must meet a variety of different requirements, in particular:
— hoher Siedepunkt,- high boiling point,
- geringe Kompressibilität,- low compressibility,
— guter Korrosionsschutz,- good corrosion protection,
— Verträglichkeit mit Elastomeren,- compatibility with elastomers,
- geringe Löslichkeit von Gasen,- low solubility of gases,
- einfache Entsorgbarkeit .
Die Eigenschaften der Bremsflüssigkeiten werden durch ihren chemischen Aufbau bestimmt. Eine Bremsflüssigkeit die alle Eigenschaften gleichzeitig besitzt ist derzeit nicht verfügbar.- easy disposal. The properties of the brake fluids are determined by their chemical structure. A brake fluid that has all the properties at the same time is currently not available.
Die heute eingesetzten Bremsflüssigkeiten sind insbesondere auf der Basis von Polyglykolether aufgebaut. Diese Bremsflüssigkeiten weisen mehrere der geforderten Eigenschaften auf. Nachteilig ist jedoch, daß sie hygroskopisch sind, was zu einer Wasseraufnahme der Bremsflüssigkeit führt. Durch die Zugabe von Borsäure kann dem entgegengewirkt werden. Dadurch entstehen aus den Polyglykolεn Boratesther. Bei höheren Wasserkonzentrationen spaltet sich der Borsäureesther in Borsäure und Polyglykolether. Mit diesem Zusatz von Borsäure entstehen Bremsflüssigkeiten die unempfindlicher gegen Wasser sind (z.B. DOT-4 und höhere) .The brake fluids used today are based in particular on polyglycol ether. These brake fluids have several of the required properties. However, it is disadvantageous that they are hygroscopic, which leads to water absorption by the brake fluid. This can be counteracted by adding boric acid. This creates borate testers from the polyglycols. At higher water concentrations, the boric acid ether splits into boric acid and polyglycol ether. This addition of boric acid creates brake fluids that are less sensitive to water (e.g. DOT-4 and higher).
Doch selbst mit verbesserten Bremsflüssigkeiten und mit konstruktiven Maßnahmen zur Verminderung des Wassereintrags steigt mit der Zeit der Wassergehalt an, gleichzeitig sinkt der Siedepunkt. Somit bestehen derzeit Wechselintervalle für die Bremsflüssigkeit im Bereich von 1-3 Jahren. Dies ist auch im Hinblick auf die Entsorgung der verbrauchten Bremsflüssigkeit problematisch, so daß grundsätzlich längere Wechselintervalle anzustreben sind.But even with improved brake fluids and with constructive measures to reduce the water input, the water content increases over time, at the same time the boiling point drops. There are currently change intervals for the brake fluid in the range of 1-3 years. This is also problematic with regard to the disposal of the used brake fluid, so that longer change intervals should always be aimed for.
In der JP62203864 ist ein Verfahren zum kontinuierlichen Entwässern von Bremsflüssigkeiten beschrieben, bei der eine Poly- merme bran in einen Bremsschlauch integriert ist. Aufgrund der unterschiedlichen Moleküldurchmesser ist die Membran nur für Wasser, jedoch nicht für die Bremsflüssigkeit durchlässig. Auf welche Weise das durch die Membran hindurchgetretene Wasser permeatseitig zur Aufrechterhaltung eines Wasserdampfpar- tialdruckgefalles weiterbehandelt wird, ist in dieser Literaturstelle nicht näher beschrieben.JP62203864 describes a method for the continuous dewatering of brake fluids, in which a polymer membrane is integrated in a brake hose. Due to the different molecular diameters, the membrane is only permeable to water, but not to the brake fluid. The way in which the water which has passed through the membrane is treated further on the permeate side to maintain a water vapor partial pressure drop is not described in any more detail in this literature reference.
In der WO 9S/48175 ist ein Verfahren zur Entwässerung von Hydraulikflüssigkeiten durch Pervaporation unter Einsatz einer
Lösungs-/Diffusionsmembran offenbart. Zur Aufrechterhaltung einer Wasserdampfpartialdruckdifferenz wird entweder innerhalb des Hydrauliksystems ein Überdruck oder permeatseitig ein Unterdruck aufgebaut.WO 9S / 48175 describes a method for dewatering hydraulic fluids by pervaporation using a Solution / diffusion membrane disclosed. In order to maintain a water vapor partial pressure difference, either an overpressure or an underpressure on the permeate side is built up within the hydraulic system.
Darüberhinauε ist dem Fachmann bekannt, bei Anwendung der Pervaporation das abgetrennte Wasser an einem permeatseitigen Kondensator zu verflüssigen. Dies ist mit einem relativ hohen apparativen Aufwand verbunden und deshalb insbesondere ein einem Kraftfahrzeug nicht ohne weiteres realisierbar.Furthermore, it is known to the person skilled in the art to liquefy the separated water on a permeate-side condenser when using pervaporation. This is associated with a relatively high outlay in terms of apparatus and therefore, in particular, cannot easily be implemented in a motor vehicle.
Aufgabe der Erfindung ist es, ein Verfahren und eine Vorrichtung zum Entwässern von Hydraulikflüssigkeiten, insbesondere Bremsflüssigkeiten, zu schaffen, das ein Entwässern bei geringem Platzbedarf in zuverlässiger Weise ermöglicht.The object of the invention is to provide a method and a device for dewatering hydraulic fluids, in particular brake fluids, which enables dewatering in a reliable manner in a small space.
Diese Aufgabe wird mit dem Verfahren nach Anspruch 1 gelöst. Eine Vorrichtung zur Durchführung des Verfahrens ist Gegenstand des Anspruchs 2.This object is achieved with the method according to claim 1. A device for performing the method is the subject of claim 2.
Gemäß der Erfindung wird das in der Hydraulikflüssigkeit enthaltene Wasser nach dem Prinzip der Pervaporation an einer für Wasser durchlässigen und für die Hydraulikflüssigkeit undurchlässigen Membran von der Hydraulikflüssigkeit abgetrennt. Damit das Wasser durch die Membran hindurch transportiert werden kann, muß ein treibende Kraft vorhanden sein. Als treibende Kraft dient ein Wasserdampfpartialdruckgefalle zwischen den beiden Seiten der Membran. Zur Aufrechterhaltung des Wasser- dampfpartialdruckgefälles ist auf der Permeatseite ein Absorb- tionsmittel (im folgenden auch Trockenmittel oder Absorbens genannt) vorhanden, an der das Wasser absorbiert wird. Unter Absorption versteht man das Eindringen von Gasen in Flüssigkeiten oder Festkörpern. Es ist somit eine Form der Sorption. Im Gegensatz zur Adsorption spielt bei der Absorption die Oberfläche eine geringere Rolle. Im Allgemeinen ist die Absorbtion mit einer Volumenvergrößerung des Absorbtionsmittels verbunden.
Das Absorbtionsmittel ist noch stärker hygroskopisch als die Hydraulikflüssigkeit selbst. Besonders geeignet sind Substanzen welche mit Wasser eine chemische Verbindung eingehen und bei welchen das Wasser erst durch Brennen bei höheren Temperaturen abgespalten werden kann. Dazu zählt zum Beispiel CaO (Branntkalk) oder MgO (Magnesia) . Das Absorbtionsmittel kann vorteilhaft auf einem inerten, porösen Trägermaterial angeordnet sein. Sobald das Absorbtionsmittel vollständig mit Wasser beladen ist, muß es ersetzt werden. Beim Einbau in das Hydrauliksyste wird das Absorptionmittel vorteilhaft derart positioniert, daß es schnell und einfach ausgetauscht werden kann.According to the invention, the water contained in the hydraulic fluid is separated from the hydraulic fluid according to the principle of pervaporation on a membrane which is permeable to water and impermeable to the hydraulic fluid. A driving force must be present so that the water can be transported through the membrane. A water vapor partial pressure drop between the two sides of the membrane serves as the driving force. In order to maintain the water vapor partial pressure gradient, an absorbent (also called desiccant or absorbent below) is present on the permeate side, on which the water is absorbed. Absorption is the penetration of gases in liquids or solids. It is therefore a form of sorption. In contrast to adsorption, the surface plays a minor role in absorption. In general, absorption is associated with an increase in volume of the absorbent. The absorbent is even more hygroscopic than the hydraulic fluid itself. Particularly suitable are substances which form a chemical compound with water and in which the water can only be split off by firing at higher temperatures. These include, for example, CaO (quicklime) or MgO (magnesia). The absorbent can advantageously be arranged on an inert, porous carrier material. Once the absorbent is fully loaded with water, it must be replaced. When installed in the hydraulic system, the absorbent is advantageously positioned such that it can be replaced quickly and easily.
Für die einzusetzenden Membranen bestehen besondere Anforderungen, insbesondere hinsichtlich deren chemischer, thermischer und mechanischer Eigenschaften. So sind z.B. bei einer Bremshydraulik Temperaturen bis 200°C und Drücke bis 200 bar üblich. Es wird deshalb vorteilhaft eine Compositmembran eingesetzt, die einen porösen, metallischen Träger und gegebenenfalls eine keramische Zwischenschicht sowie einem dichten Polymerfilm, der die eigentliche Trennschicht (Lösungs-/Diffusionsmembran) darstellt, umfaßt. Für diese Trennschicht kommen besonders vorteilhaft folgende Polymere zum Einsatz:There are special requirements for the membranes to be used, particularly with regard to their chemical, thermal and mechanical properties. For example, With brake hydraulics, temperatures up to 200 ° C and pressures up to 200 bar are common. It is therefore advantageous to use a composite membrane which comprises a porous, metallic support and optionally a ceramic intermediate layer and a dense polymer film which represents the actual separation layer (solution / diffusion membrane). The following polymers are used particularly advantageously for this separating layer:
- Polyamid, insbesondere PA 6 oder ein Mischpolymer aus PA6,PA66,PA136;- Polyamide, in particular PA 6 or a mixed polymer made of PA6, PA66, PA136;
- Polyimid;- polyimide;
- Copolymer Ethylen-Propylen (EP. und dessen vernetzte Formen EPM oder EPDM.- Copolymer ethylene-propylene (EP. And its cross-linked forms EPM or EPDM.
Die Erfindung kann insbesondere in einem Bre ssystem, vor allem in einem Kraftfahrzeug eingesetzt werden.The invention can be used in particular in a bre system, especially in a motor vehicle.
Die Membran kann z.B. zylinderförmig ausgebildet sein und in einem schlauchartigen Leitungsabschnitt des Bremssystems angeordnet sein. Besonders geeignet ist hierbei die Anschlußleitung zum Bremssattel, wobei die Membran den dem Bremssattel benachbarten Endabschnitt der Leitung bildet. Die Membran ist in die-
ser Ausführung über ihren gesamten Außenumfang von dem Absorbtionsmittel umgeben.The membrane can be cylindrical, for example, and can be arranged in a hose-like line section of the brake system. The connecting line to the brake caliper is particularly suitable here, the membrane forming the end section of the line adjacent to the brake caliper. The membrane is in this Ser execution surrounded by the absorbent over its entire outer circumference.
In weiteren vorteilhaften Ausführung kann die Membran auch eben ausgebildet sein. In dieser Form können Membran und Absorbtionsmittel besonders vorteilhaft im Boden eines Hydraulikkolbens innerhalb des Bremssystems angeordnet sein.In a further advantageous embodiment, the membrane can also be flat. In this form, the membrane and absorbent can be arranged particularly advantageously in the bottom of a hydraulic piston within the brake system.
Bei Bremssystemen, bei denen die Bremsflüssigkeit in einem Kreislauf geführt wird, ist auch ein zentraler Einbau im Bereich eines Bremsflüssigkeitsvorratsbehälters vorteilhaft.In brake systems in which the brake fluid is conducted in a circuit, a central installation in the area of a brake fluid reservoir is also advantageous.
Die Vorteile der Erfindung liegen im wesentlichen darin, daß ein zuverlässiges und platzsparendes Entwässern der Hydraulikflüssigkeit erreicht wird. Insbesonderes können die Wechselintervalle der Hydraulikflüssigkeit wesentlich erhöht werden. Die erfindungsgemäße Funktion ist bei Drücken bis mindestens 200 bar sowie bei Temperaturen bis mindestens 200 °C gewährleistet. Die Entwässerung ist insbesondere auch unabhängig von den atmo- spährisehen Umgebungsbedingungen.The advantages of the invention are essentially that reliable and space-saving dewatering of the hydraulic fluid is achieved. In particular, the change intervals of the hydraulic fluid can be increased significantly. The function according to the invention is guaranteed at pressures up to at least 200 bar and at temperatures up to at least 200 ° C. The drainage is particularly independent of the atmospheric ambient conditions.
BeispieleExamples
Im Laborversuch wurden 20g CaO als Trockenmittel mit einer PA6 Membran (20μm Dicke, Fläche 45cm2) und 120g einer Hydraulikflüssigkeit DOT4+ mit 3g H20 bei Temperaturen zwischen 160 und 180°C in Kontakt gebracht. Dabei sank der Wassergehalt von anfänglichen 2,6% auf 1% nach 70 Stunden.In the laboratory test, 20g CaO as a drying agent were brought into contact with a PA6 membrane (20μm thickness, area 45cm 2 ) and 120g a hydraulic fluid DOT4 + with 3g H 2 0 at temperatures between 160 and 180 ° C. The water content dropped from the initial 2.6% to 1% after 70 hours.
Bei einem weiteren Versuch mit 3 , 4g CaO und einer PA6 Membran wurde der Wassergehalt aus 40g DOT4+ von 2,5% Wasser bei 60°C in 300 Stunden auf 0,5% Wassergehalt reduziert. Dabei wurden 0,8g Wasser entfernt.In a further experiment with 3.4 g of CaO and a PA6 membrane, the water content from 40 g of DOT4 + was reduced from 2.5% water at 60.degree. C. in 300 hours to 0.5% water content. 0.8 g of water were removed.
Bei einem weiteren Versuch mit 3 , 4g CaO und einer PA6 Membran wurde der Wassergehalt aus 40g DOT4+ von 2,5% Wasser bei 100°C
in 83 Stunden auf 0,5% Wassergehalt reduziert. Dabei wurden 0,8g Wasser entfernt.In a further experiment with 3.4 g of CaO and a PA6 membrane, the water content was 40 g of DOT4 + from 2.5% of water at 100 ° C. reduced to 0.5% water content in 83 hours. 0.8 g of water were removed.
Vorteilhafte Ausführungen der Erfindung werden im folgenden anhand von Zeichnungen näher erläutert. Sie zeigen jeweils Vorrichtungen zur Durchführung des erfindungsgemäßen Verfahrens.Advantageous embodiments of the invention are explained in more detail below with reference to drawings. They each show devices for carrying out the method according to the invention.
Fig. 1 zeigt eine erste erfindungsgemäße Ausführung an einem Bremssattel 1 einer ansonsten nicht näher dargestellten Rad- bremse eines Kraftfahrzeugs. In einer gehäuseseitigen Anschluß- verschraubung 2 der Bremshydraulik ist die erfindungsgemäße Vorrichtung 3 zur Entfeuchtung der Bremsflüssigkeit über einen Schraubanschluß 4 mit dem Bremssattel 1 verbunden. Die Vorrichtung 3 umfaßt eine rohrförmig ausgebildete Membran 5 in direktem Kontakt zur Bremsflüssigkeit. Die Membran ist erfindungsgemäß von Trockenmittel 6 umgeben, welches die durch die Membran transportierte Feuchte aufnimmt und bindet. Über eine Ver- schraubung 8 ist ein Bremsschlauch 7 zur Druckversorgung des Bremssattels 1 angeschlossen.1 shows a first embodiment according to the invention on a brake caliper 1 of an otherwise not shown wheel brake of a motor vehicle. In a housing-side screw connection 2 of the brake hydraulics, the device 3 according to the invention for dehumidifying the brake fluid is connected to the brake caliper 1 via a screw connection 4. The device 3 comprises a tubular membrane 5 in direct contact with the brake fluid. According to the invention, the membrane is surrounded by desiccant 6, which absorbs and binds the moisture transported through the membrane. A brake hose 7 for supplying pressure to the brake caliper 1 is connected via a screw connection 8.
Fig. 2 zeigt eine weitere erfindungsgemäße Ausführung. Der Bremssattel 1 ist im wesentlich identisch zu dem in Fig. 1 dargestellten. Allerdings ist die erfindungsgemäße Entfeuch- tungsvorrichtung nicht im Bremsschlauch 7 integriert, sondern als separate bauliche Einheit direkt auf den Bremssattel aufgeschraubt (Versehraubung 13). Sie steht mit dem Druckraum des Bremssattels 1 in Kontakt. Die Ξntfeuchtungsvorrichtung kann besonders vorteilhaft an der Stelle einer hier nicht dargestellten Entlüftungsschraube angeordnet sein. Die mit Feuchtigkeit beladene Bremsflüssigkeit gelangt in den Raum 12, in welchem sie sich vor der flach ausgebildeten Membran ausbreiten kann. Auf der Membranrückseite befindet sich das Trocknungsmittel 10, welches die Feuchtigkeit aufnimmt. Im Unterschied zu der in Fig. 1 gezeigten Ausführung liegt die Entfeuchtungsvorrichtung nicht im Durchfluß einer Hydraulikleitung. Ein Austausch der Vorrichtung nach Art einer Patrone wird vereinfacht.
Dieser Austausch kann mit der Entlüftung des Bremssattels verbunden werden.2 shows a further embodiment according to the invention. The brake caliper 1 is essentially identical to that shown in FIG. 1. However, the dehumidifying device according to the invention is not integrated in the brake hose 7, but instead is screwed directly onto the brake caliper as a separate structural unit (spoilage 13). It is in contact with the pressure chamber of the brake caliper 1. The dehumidifying device can be arranged particularly advantageously in the place of a ventilation screw, not shown here. The brake fluid loaded with moisture enters space 12, in which it can spread out in front of the flat membrane. On the back of the membrane is the drying agent 10, which absorbs the moisture. In contrast to the embodiment shown in FIG. 1, the dehumidifying device does not lie in the flow through a hydraulic line. An exchange of the device in the manner of a cartridge is simplified. This exchange can be combined with bleeding the brake caliper.
Fig. 3 zeigt eine weitere erfindungsgemäße Ausführung. Dargestellt ist ein Bremssattel 14 in einem Teilschnitt. In einem Zylindergehäuse 16 ist ein Bremskolben 15 verschiebbar angeordnet. Die erfindungsgemäße Entfeuchtungsvorrichtung mit Membran 19 und Trockenmittel 20 ist auf der Stirnseite des Zylindergehäuses verschraubt. Die Bremsflüssigkeit im Druckbereich hinter dem Kolben 15 kann somit direkt mit der Membran 19 in Kontakt kommen und ihre Feuchtigkeit über die Membran 19 an das Trocknungsmittel 20 abgeben. Diese Ausführung erlaubt somit eine Entfeuchtung unmittelbar im Bereich einer drohenden Dampfblasenbildung. Außerdem kann die Entfeuchtungsvorrichtung in der gezeigten Position leicht und schnell ausgetauscht werden.3 shows a further embodiment according to the invention. A brake caliper 14 is shown in a partial section. A brake piston 15 is arranged displaceably in a cylinder housing 16. The dehumidifying device according to the invention with membrane 19 and desiccant 20 is screwed onto the front side of the cylinder housing. The brake fluid in the pressure area behind the piston 15 can thus come into direct contact with the membrane 19 and release its moisture via the membrane 19 to the drying agent 20. This design thus allows dehumidification directly in the area of impending vapor bubble formation. In addition, the dehumidifier can be replaced easily and quickly in the position shown.
Fig. 4 zeigt eine weitere, besonders bevorzugte Ausgestaltung der Erfindung. Hier ist der Kolben 21 innerhalb des Bremssattels 14 derart gestaltet, daß die Membran 23 im Kolben integriert ist. Ähnlich wie in Fig. 3 erlaubt diese Ausführung eine Entfeuchtung im Bereich der drohenden Dampfblasenbildung. In dem auf der Rückseite der Membran gebildeten Raum befindet sich das Trocknungsmittel 22. Mit dieser Ausführung der Erfindung kann ein relativ großes Volumen an Trocknungsmittel unmittelbar in der Radbremse vorhanden sein, so daß eine lang anhaltende Entfeuchtungsleistung mit entsprechend erweiterten Wechselintervallen erreicht wird.
4 shows a further, particularly preferred embodiment of the invention. Here, the piston 21 within the caliper 14 is designed such that the membrane 23 is integrated in the piston. Similar to Fig. 3, this embodiment allows dehumidification in the area of impending vapor bubble formation. The drying agent 22 is located in the space formed on the rear side of the membrane. With this embodiment of the invention, a relatively large volume of drying agent can be present directly in the wheel brake, so that a long-lasting dehumidification performance is achieved with correspondingly extended changing intervals.
Claims
Verfahren zum Entwässern von Hydraulikflüssigkeiten innerhalb eines Hydrauliksystems, wobei in der Hydraulikflüssigkeit enthaltenes Wasser nach dem Prinzip der Pervaporation an einer für Wasser durchlässigen und für die Hydraulikflüssigkeit undurchlässigen Membran (5,11,19,23), in deren Bereich ein Partialdruckgefälle für Wasser aufrechterhalten wird, von der Hydraulikflüssigkeit abgetrennt wird, d a d u r c h g e k e n n z e i c h n e t , daß per- meatseitig zur Aufrechterhaltung des Wasserdampfpar- tialdruckgefälles das abgetrennte Wasser an einem Absorbtionsmittel (6, 10,20,22) absorbiert wird.Method for dewatering hydraulic fluids within a hydraulic system, wherein water contained in the hydraulic fluid according to the principle of pervaporation on a membrane which is permeable to water and impermeable to the hydraulic fluid (5, 11, 19, 23), in the area of which a partial pressure drop for water is maintained , is separated from the hydraulic fluid, characterized in that the separated water is absorbed by an absorbent (6, 10, 20, 22) on the perm side to maintain the water vapor partial pressure drop.
Vorrichtung zur Durchführung des Verfahrens nach Anspruch 1, d a d u r c h g e k e n n z e i c h n e t , daß innerhalb eines Hydrauliksystems eine für Wasser durchlässige und für Hydraulikflüssigkeit undurchlässige Membran (5,11,19,23) vorgesehen ist, und permeatseitig ein Absorbtionsmittel (6, 10,20,22) vorhanden ist.Device for carrying out the method according to Claim 1, characterized in that a membrane (5, 11, 19, 23) which is permeable to water and impermeable to hydraulic fluid is provided within a hydraulic system, and an absorbent (6, 10, 20, 22) is present on the permeate side is.
Vorrichtung nach Anspruch 2 , d a d u r c h g e k e n n z e i c h n e t , daß das Absorbtionsmittel (6, 10,20,22) CaO oder MgO ist.Apparatus according to claim 2, d a d u r c h g e k e n n z e i c h n e t that the absorbent (6, 10,20,22) is CaO or MgO.
Vorrichtung nach Anspruch 2 oder 3 , d a d u r c h g e k e n n z e i c h n e t , daß das Absorbtionsmittel auf einem inerten, porösen Trägermaterial angeordnet ist.Apparatus according to claim 2 or 3, d a d u r c h g e k e n n e e e c h n e t that the absorbent is arranged on an inert, porous support material.
Vorrichtung nach Anspruch 2 , 3 oder 4 ,
d a d u r c h g e k e n n z e i c h n e t , daß die Membran eine Compositmembran ist, bei der ein Polymermaterial auf einem metallischen und/oder keramischen Träger angeordnet ist.Device according to claim 2, 3 or 4, characterized in that the membrane is a composite membrane in which a polymer material is arranged on a metallic and / or ceramic carrier.
6. Vorrichtung nach Anspruch 5, d a d u r c h g e k e n n z e i c h n e t , daß das Polymermaterial ein6. The device of claim 5, d a d u r c h g e k e n n z e i c h n e t that the polymer material
- Polyamid, z.B. PA6, oder ein Polyamid-Mischpolymer, z.B. aus PA6, PA66, PA136; oder ein- polyamide, e.g. PA6, or a polyamide copolymer, e.g. from PA6, PA66, PA136; or a
- Poiyimid, oder ein- Poiyimid, or one
- Copolymer Ethylen-Propylen EP oder eines seiner vernetzten Formen EPM oder EPDM ist.- Copolymer is ethylene-propylene EP or one of its cross-linked forms EPM or EPDM.
7. Vorrichtung nach einem der Ansprüche 2 bis 6, d a d u r c h g e k e n n z e i c h n e t , daß die Hydraulikflüssigkeit eine Bremsflüssigkeit ist und das Hydrauliksystem ein Bremssystem ist.7. Device according to one of claims 2 to 6, that the hydraulic fluid is a brake fluid and the hydraulic system is a brake system.
8. Vorrichtung nach Anspruch 7 , d a d u r c h g e k e n n z e i c h n e t , daß Membran8. The device according to claim 7, d a d u r c h g e k e n n z e i c h n e t that membrane
(5) und Absorbtionsmittel (6) in einem schlauchartigen Lei- tungsabschnitt (7) des Bremssystems integriert ist.(5) and absorbent (6) is integrated in a hose-like line section (7) of the brake system.
9. Vorrichtung nach Anspruch 8, d a d u r c h g e k e n n z e i c h n e t , daß die Membran (5) zylindrisch ausgebildet ist.9. The device according to claim 8, d a d u r c h g e k e n n z e i c h n e t that the membrane (5) is cylindrical.
10. Vorrichtung nach Anspruch 7, d a d u r c h g e k e n n z e i c h n e t , daß die Membran (11, 19, 23) eben ausgebildet ist.10. The apparatus of claim 7, d a d u r c h g e k e n n z e i c h n e t that the membrane (11, 19, 23) is flat.
11. Vorrichtung nach einem der vorangehenden Ansprüche 7 oder 10, d a d u r c h g e k e n n z e i c h n e t , daß Membran (11) und Absorbtionsmittel (10) in einer separaten baulichen Einheit (9) auf der Außenoberfläche eines Bremssattels (1) des Bremssystems befestigt sind.
11. Device according to one of the preceding claims 7 or 10, characterized in that the membrane (11) and absorbent (10) in a separate structural unit (9) on the outer surface of a brake caliper (1) of the brake system are attached.
12. Vorrichtung nach einem der vorangehenden Ansprüche 7 oder 10, d a d u r c h g e k e n n z e i c h n e t , daß Membran (19) und Absorbtionsmittel (20) innerhalb einer Bremszylindergehäusewandung (17) des Bremsssystems angeordnet sind.12. Device according to one of the preceding claims 7 or 10, d a d u r c h g e k e n n z e i c h n e t that the membrane (19) and absorbent (20) are arranged within a brake cylinder housing wall (17) of the brake system.
13. Vorrichtung nach einem der vorangehenden Ansprüche 7 oder 10, d a d u r c h g e k e n n z e i c h n e t , daß Membran (23) und Absorbtionsmittel (22) innerhalb eines Bremskolbens (21) des Bremssystems angeordnet sind.13. Device according to one of the preceding claims 7 or 10, d a d u r c h g e k e n n z e i c h n e t that membrane (23) and absorbent (22) are arranged within a brake piston (21) of the brake system.
1 . Vorrichtung nach einem der vorangehenden Ansprüche 7 oder 10, d a d u r c h g e k e n n z e i c h n e t , daß Membran und Absorbtionsmittel innerhalb eines oder benachbart zu einem Vorratsbehälter für die Bremsflüssigkeit des Bremssystems angeordnet sind.
1 . Device according to one of the preceding claims 7 or 10, that the membrane and absorbent are arranged within or adjacent to a reservoir for the brake fluid of the brake system.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19923415A DE19923415C2 (en) | 1999-05-21 | 1999-05-21 | Process for dewatering hydraulic fluids and device for carrying out the process |
DE19923415.9 | 1999-05-21 |
Publications (1)
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WO2000071233A1 true WO2000071233A1 (en) | 2000-11-30 |
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Application Number | Title | Priority Date | Filing Date |
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PCT/EP2000/003126 WO2000071233A1 (en) | 1999-05-21 | 2000-04-07 | Method for dewatering hydraulic fluids and device for carrying out said method |
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DE (1) | DE19923415C2 (en) |
WO (1) | WO2000071233A1 (en) |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
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DE10102240A1 (en) * | 2001-01-19 | 2002-07-25 | Daimler Chrysler Ag | Dehumidifier system for motor vehicle brake and clutch systems consists of loose granulate in connection hose between clutch and brake/clutch fluid container |
DE10252148B3 (en) * | 2002-11-09 | 2004-02-12 | Daimlerchrysler Ag | Process for dewatering a hydraulic fluid stream in a hydraulic system comprises removing water from the hydraulic fluid by pervaporation on a membrane which is impinged on the permeate side with a rinsing stream |
DE102021204652A1 (en) * | 2021-05-07 | 2022-11-10 | Sms Group Gmbh | Cleaning device for liquids, in particular for oil liquids |
Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS62203864A (en) * | 1986-03-03 | 1987-09-08 | Mazda Motor Corp | Brake device for vehicle |
WO1989011052A1 (en) * | 1988-05-03 | 1989-11-16 | Lindsay Ernest Derriman | Brake assembly |
JPH0462363A (en) * | 1990-06-29 | 1992-02-27 | Nippondenso Co Ltd | Water separator for refrigeration cycle |
WO1993011859A1 (en) * | 1991-12-10 | 1993-06-24 | Pall Corporation | Contaminant removal system and process |
DE4201565A1 (en) * | 1992-01-22 | 1993-07-29 | Teves Gmbh Alfred | Container for vehicle brake fluid - has gas permeable but fluid impermeable membrane set on opening |
JPH05248735A (en) * | 1992-03-03 | 1993-09-24 | Mitsui Petrochem Ind Ltd | Compression type freezing machine |
US5610878A (en) * | 1994-12-20 | 1997-03-11 | Pont Saint-Germain Sa | Desiccation capsule and article provided with said capsule |
DE19717043A1 (en) * | 1997-04-23 | 1998-06-25 | Daimler Benz Ag | Process equipment, use of equipment and/or process for degassing and/or dewatering hydraulic fluids |
-
1999
- 1999-05-21 DE DE19923415A patent/DE19923415C2/en not_active Expired - Fee Related
-
2000
- 2000-04-07 WO PCT/EP2000/003126 patent/WO2000071233A1/en active Application Filing
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS62203864A (en) * | 1986-03-03 | 1987-09-08 | Mazda Motor Corp | Brake device for vehicle |
WO1989011052A1 (en) * | 1988-05-03 | 1989-11-16 | Lindsay Ernest Derriman | Brake assembly |
JPH0462363A (en) * | 1990-06-29 | 1992-02-27 | Nippondenso Co Ltd | Water separator for refrigeration cycle |
WO1993011859A1 (en) * | 1991-12-10 | 1993-06-24 | Pall Corporation | Contaminant removal system and process |
DE4201565A1 (en) * | 1992-01-22 | 1993-07-29 | Teves Gmbh Alfred | Container for vehicle brake fluid - has gas permeable but fluid impermeable membrane set on opening |
JPH05248735A (en) * | 1992-03-03 | 1993-09-24 | Mitsui Petrochem Ind Ltd | Compression type freezing machine |
US5610878A (en) * | 1994-12-20 | 1997-03-11 | Pont Saint-Germain Sa | Desiccation capsule and article provided with said capsule |
DE19717043A1 (en) * | 1997-04-23 | 1998-06-25 | Daimler Benz Ag | Process equipment, use of equipment and/or process for degassing and/or dewatering hydraulic fluids |
WO1998048175A1 (en) * | 1997-04-23 | 1998-10-29 | Daimlerchrysler Ag | Method for dehydrating and/or degassing hydraulic fluids, device for carrying out said method and use of said device |
Non-Patent Citations (5)
Title |
---|
DATABASE WPI Derwent World Patents Index; AN 1992-119447, XP002145536 * |
DATABASE WPI Derwent World Patents Index; AN 1993-340377, XP002145537 * |
PATENT ABSTRACTS OF JAPAN vol. 012, no. 057 (M - 670) 20 February 1988 (1988-02-20) * |
PATENT ABSTRACTS OF JAPAN vol. 016, no. 258 (M - 1264) 11 June 1992 (1992-06-11) * |
PATENT ABSTRACTS OF JAPAN vol. 018, no. 006 (M - 1537) 7 January 1994 (1994-01-07) * |
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DE19923415C2 (en) | 2002-07-11 |
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