DK142353B - STEERING MECHANISM FOR MOTOR VEHICLES - Google Patents
STEERING MECHANISM FOR MOTOR VEHICLES Download PDFInfo
- Publication number
- DK142353B DK142353B DK177374A DK177374A DK142353B DK 142353 B DK142353 B DK 142353B DK 177374 A DK177374 A DK 177374A DK 177374 A DK177374 A DK 177374A DK 142353 B DK142353 B DK 142353B
- Authority
- DK
- Denmark
- Prior art keywords
- pressure
- line
- control mechanism
- valve
- valve piston
- Prior art date
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D5/00—Power-assisted or power-driven steering
- B62D5/06—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle
- B62D5/30—Safety devices, e.g. alternate emergency power supply or transmission means to ensure steering upon failure of the primary steering means
- B62D5/32—Safety devices, e.g. alternate emergency power supply or transmission means to ensure steering upon failure of the primary steering means for telemotor systems
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Transportation (AREA)
- Mechanical Engineering (AREA)
- Power Steering Mechanism (AREA)
- Fluid-Pressure Circuits (AREA)
- Safety Valves (AREA)
Description
(^) (11> FREMLÆGGELSESSKRIFT 142353 DANMARK («υ lnt.CI.> B 62 D 5/06 • (21) Ansøgning nr. 1 773/7^ (22) Indleveret den 29· mar. 197^ (24) Lebedag 29, mar. 197^ (44) Ansøgningen fremlagt og Qn(^) (11> PUBLICATION MANUAL 142353 DENMARK («υ lnt.CI.> B 62 D 5/06 • (21) Application no. 1 773/7 ^ (22) Filed on 29 Mar 197 ^ (24) Life day 29, Mar. 197 ^ (44) The application presented and Qn
fremlaeggelsessfcriftet offentliggjort den 2U , OKt · I 9oUthe presentation document published on 2U, October · 9oU
DIREKTORATET FOR ^ PATENT- OG VAREMÆRKEVÆSENET <30> P"0**1 begasret fra den 16. apr. 1973a 2319155a DE (71) DEERE & COMPANY, Moline, Illinois 61 265a US.DIRECTORATE OF THE PATENT & TRADEMARKET <30> P "0 ** 1 gassed from Apr 16, 1973a 2319155a DE (71) DEERE & COMPANY, Moline, Illinois 61 265a US.
(72) Opfinder: Wolfgang Roth, 6660 Zweibrueckena Zweibrueckenstr. 9, DE.(72) Inventor: Wolfgang Roth, 6660 Zweibrueckena Zweibrueckenstr. 9, DE.
(74) Fuldmægtig under sagens behandling:(74) Plenipotentiary in the proceedings:
Firmaet Chae. Hude.The company Chae. Hude.
(54) Styremekanisme til motorkøretøjer.(54) Motor vehicle steering mechanism.
Opfindelsen angår en hydrostatisk styremekanisme til motorkøretøjer og med en pumpe, som over en første trykledning med en kontraventil, der har et ventilstempel med tætningselementer, er forbundet med en styremekanisme, som over en tilbageløbsledning er tilsluttet en samlebeholder og over en første og anden styretrykledning er i forbindelse med en styrecylinder, idet der i tilbageløbsledningen findes en anden kontraventil, der spærrer for strømning af trykmedium til samlebeholderen, hvilken anden kontraventil over en mekanisk eller hydraulisk mekanisme er forbundet med trykledningen og ved forhåndenværende servotryk holdes i åben stilling ved hjælp af den mekaniske eller hydrauliske mekanisme.BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a hydrostatic steering mechanism for motor vehicles and to a pump connected over a first pressure line with a non-return valve having a valve piston with sealing elements, to a control mechanism connected over a return line to a collecting tank and over a first and second control pressure line. in connection with a control cylinder, in which there is in the reflux line another non-return valve which prevents flow of pressure medium to the collector, which second non-return valve is connected to the pressure line via a mechanical or hydraulic mechanism and is held in the open position by the mechanical servo pressure. or hydraulic mechanism.
2 U23532 U2353
Fra beskrivelsen til USA patent nr. 2.836.960 kendes en hydrostatisk styremekanisme til motorkøretøjer med en hydrostatisk styreenhed, som dels er tilsluttet til en primær kreds med hydraulikpumpe og samle-beholder og dels til en sekundær kreds med mindst én styrecylinder, og hvor et ventilarrangement er indskudt mellem den hydrostatiske styreenhed og en hydraulikpumpe i primærkredsen. Ventilarrangementet har et i en hydraulikledning som kontraventil udformet ventilstempel og et første tætningselement, der kan afspærre pumpens hydraulikledning fra en trykledning til styreenheden, samt et andet tætningselement, som kan afspærre en hydraulikledning til styreenheden fra en tilbageløbskanal til samlebeholderen i en første stilling af ventil-_stemplet.From the specification of US Patent No. 2,836,960, a hydrostatic steering mechanism is known for motor vehicles with a hydrostatic control unit, which is connected partly to a primary circuit with hydraulic pump and collector and partly to a secondary circuit with at least one steering cylinder, and in which a valve arrangement is inserted between the hydrostatic control unit and a hydraulic pump in the primary circuit. The valve arrangement has a valve piston designed in a hydraulic line as a check valve and a first sealing element which can block the pump hydraulic line from a pressure line to the control unit, and a second sealing element which can block a hydraulic line to the control unit from a return channel to the collector in a first position of the valve. _stemplet.
Formålet med opfindelsen er at tilvejebringe en styremekanisme af den omhandlede art, hvori viskositeten af en olieluftblanding, der er lavere end viskositeten af ren olie, kan aftastes, og udløbet af styrecylinderens differens-trykoliemængde fra hydrauliksystemet ved svigt af hydraulikpumpen og indstrømning af luft, så systemet kommer til at arbejde med olie-luftblanding, kan undgås.The object of the invention is to provide a control mechanism of the kind in which the viscosity of an oil-air mixture lower than the viscosity of pure oil can be sensed and the discharge of the differential pressure oil quantity of the control cylinder from the hydraulic system by failure of the hydraulic pump and inflow of air, the system will work with oil-air mixture can be avoided.
Dette er ifølge opfindelsen opnået ved, at ventilstemplet har en drøvleåbning, som forbinder pumpens trykledning med en afløbskanal eller en styreledning, og som har en længde, der er lig med eller større end diameteren af drøvleåbningen, hvorhos der i strømningsretningen bag den første drøvleåbning findes endnu et drøvlested (styrekant, tætningselement), hvis gennemstrømningstværsnit er foranderligt i afhængighed af trykket i hydraulikpumpens trykledning.This is achieved according to the invention in that the valve piston has a throttle opening which connects the pump pressure line to a drain channel or a control line and has a length equal to or greater than the diameter of the throttle opening, which is found in the flow direction behind the first throttle opening. another throttle location (guide edge, sealing element) whose flow cross section is variable depending on the pressure in the hydraulic pump pressure line.
Ved hjælp af den langtrukne boring, hvis længde er større end diameteren, opstår der i afhængighed af viskositeten et trykfald i drøvleåbningen, hvilket medfører en ændring af ventilstemplets stilling ved hjælp af en trykfjeder. Det indstillelige drøvlested i afløbskanalen bevirker, at volumenmængden af det gennem drøvleåbningen strømmende trykmedium til afløbsledningen begrænses ved stigende tryk, således at den effektive strømning gennem pumpens trykledning til styreenheden forbliver konstant. Endvidere hindres, at differens -trykoliemængden, dersom pumpen svigter, løber ind i samlebeholderen, d.v.s. at anlægget stadig fungerer også efter flere styreoperationer. Samtidig bevirker ventilstemplet, at indsuget luft ikke når ind i styreenheden, og at styreanlægget også fungerer stabilt 3 142353 ved indsugning af luft-olieblanding. Ved en fordelagtig udførelses-form for styremekanismen ifølge opfindelsen ligger to tætnings-elementer i deres første stilling an mod elastiske tætningsorganer. Herved opnås en lækagefri tætning ved tilbageløbsledningen til sam-lebeholderen og pumpens trykledning.By means of the elongated bore, whose length is greater than the diameter, a pressure drop in the throttle opening is caused, depending on the viscosity, which causes a change in the position of the valve piston by means of a compression spring. The adjustable throttle location in the drain channel causes the volume of the pressure medium flowing through the throttle opening to the drain line to be limited by increasing pressure so that the effective flow through the pump pressure line to the control unit remains constant. In addition, if the pump failure, the differential pressure oil quantity is prevented from flowing into the collector, i.e. that the plant still works even after several control operations. At the same time, the valve piston ensures that the suction air does not reach into the control unit and that the control system also operates stably when sucking air-oil mixture. In an advantageous embodiment of the control mechanism according to the invention, two sealing elements in their first position abut resilient sealing means. Thereby, a leak-free seal is obtained at the return line of the collector and the pump pressure line.
Endvidere er det ifølge opfindelsen fordelagtigt, at der mellem styremekanismens trykledning og tilbageløbskanalen til samlebeholde-ren er indskudt en trykbegrænsningsventil. Dette bevirker, at trykstødet i styreanlægget ved den første stilling af ventilstemplet kan reduceres over afløbsledningen til samlebeholderen.Furthermore, according to the invention, it is advantageous that a pressure limiting valve is inserted between the pressure line of the control mechanism and the return channel to the collector. This means that, at the first position of the valve piston, the thrust in the control system can be reduced over the drain line to the collector.
Endelig foreslås det ifølge opfindelsen, at der til styreenhedens tilbageløbsledning tilsluttes en trykbeholder før det mellem tilbageløbsledningen og afløbskanalen til samlebeholderen beliggende tætningselement, regnet i strømningsretningen, til optagelse af diffe-renstrykoliemængden.Finally, according to the invention, it is proposed that a pressure vessel be connected to the control unit's return line before the sealing element, located in the flow direction, located between the return line and the drain channel for the collecting vessel, to receive the diffuser pressure oil quantity.
Det indstillelige drøvlested kan på simpel måde være dannet af en styrekant på ventilstemplet og en styrekant i området ved afløbskanalen.The adjustable throttle location may simply be formed by a guide edge of the valve piston and a guide edge in the area of the drain channel.
Ifølge opfindelsen er det endvidere hensigtsmæssigt,at ventilstemplet har en gennemgående aksial boring, som på en del af sin længde er udformet som en drøvleåbning og ved den ene ende over en med en drøvle-åbning forsynet dæmpningsplade er forbundet med et trykrum, der optager fjederen til påvirkning af stemplet. Ved anvendelse af daemp-ningspladen i forbindelse med trykrummet holdes ventilstemplets oscillerende svingninger under arbejdsprocessen små.Furthermore, according to the invention, it is desirable that the valve piston has a through axial bore which is formed as part of its length as a throttle opening and at one end above a damping plate provided with a throttle opening is connected to a pressure chamber which accommodates the spring. to influence the piston. When using the damping plate in connection with the pressure chamber, the oscillating oscillations of the valve piston are kept small during the working process.
Opfindelsen forklares nærmere i det følgende i forbindelse med to udførelseseksempler for styremekanismen ifølge opfindelsen og under henvisning til tegningen, hvor fig. 1 viser en skematisk fremstilling af en styremekanisme ifølge opfindelsen, fig. 2 en første udførelsesform for den i styremekanismen forekommende ventilblok, 4 142353 fig. 3 ventilblokken med påbygget trykbeholder, fig. 4 et koblingsskema for en anden udførelsesform for styremekanismen ifølge opfindelsen og fig. 5 ventilblokken i styremekanismen ifølge fig. 4.The invention will be explained in more detail below with reference to two embodiments of the control mechanism according to the invention and with reference to the drawing, in which fig. 1 is a schematic representation of a control mechanism according to the invention; FIG. 2 shows a first embodiment of the valve block present in the control mechanism; FIG. 3 shows the valve block with built-in pressure vessel, fig. 4 is a schematic diagram of another embodiment of the control mechanism according to the invention; and FIG. 5 shows the valve block in the control mechanism of FIG. 4th
På tegningen betegner 10 en hydraulikpumpe, som over en sugeledning 12 er forbundet med en samlebeholder 14. Afgangen fra hydraulikpumpen 10 er over en hydraulikledning 16 tilsluttet en i en ventilblok 18 udformet trykkanal 20, som er forbundet med en aksial boring 24, der optager et ventilstempel 22. Den aksiale boring 24 står over en trykkanal 26 og over en trykledning 28 i forbindelse med en hydrostatisk styremekanisme 30, som over en hydraulikledning 32 står i forbindelse med en i ventilblokken 18 udformet afløbskanal 34. Afløbskanalen 34 er over den aksiale boring 24 forbundet med en anden i ventilblokken 18 udformet afløbskanal 36, som over endnu en hydraulikledning 38 er tilsluttet samlebeholderen 14. Parallelt med den aksiale boring 24 findes der i ventilblokken 18 en tilbagestrømningskanal 40, som er forbundet med afløbskanalen 36 og over en trykbegrænsningsventil 42 står i forbindelse med trykkanalen 26.In the drawing, 10 denotes a hydraulic pump which is connected to a collecting vessel over a suction line 12. valve piston 22. The axial bore 24 is over a pressure channel 26 and over a pressure line 28 in connection with a hydrostatic control mechanism 30, which over a hydraulic line 32 is connected to a drain channel 34 formed in the valve block 18. The drain channel 34 is over the axial bore 24 connected to another drain channel 36 formed in the valve block 18, which is connected to a further container 14 over another hydraulic line 38. In parallel with the axial bore 24 there is in the valve block 18 a back flow channel 40 connected to the drain channel 36 and over a pressure limiting valve 42. connection to the pressure duct 26.
Ventilstemplet 22 har en aksial boring 44, som er forsynet med en i den midterste del af boringen anbragt drøvleåbning 46. Ved den i strømningsretningen nederste ende af ventilstemplet 22 befinder sig en dæmpningsplade 48, som ligeledes har en eller flere drøvleåbnin-ger 50, således at trykmediet fra den aksiale boring 44 i ventilstemplet 22 kan strømme til et efter dæmpningspladen 48 indskudt trykrum 52, der også tjener til at optage en fjeder 54, som virker mellem den ene ende af trykrummet 52 og den nederste ende af ventilstemplet, således at ventilstemplet 22 trykkes mod en i ventilblokken 18 anbragt lukkeskrue 56, når der ikke transporteres noget trykmedium af hydraulikpumpen 10.The valve piston 22 has an axial bore 44 which is provided with a throttle opening 46 located in the middle part of the bore. At the lower end of the valve piston 22 is a damping plate 48 which also has one or more throttle openings 50, thus the pressure medium from the axial bore 44 in the valve piston 22 can flow to a pressure space 52 inserted after the damping plate 48, which also serves to receive a spring 54 which acts between one end of the pressure chamber 52 and the lower end of the valve piston, so that the valve piston 22 is pressed against a closing screw 56 located in the valve block 18 when no pressure medium is conveyed by the hydraulic pump 10.
Ventilstemplet 22 har tre tætningselementer 58, 62 og 66, af hvilke det første tætningselement 58 er anbragt mellem afløbskanalen 34 og hydraulikledningen 16 og derved i en første stilling af ventilstem- 142353 5 plet 22 adskiller trykkanalen 20 fra trykkanalen 26 til styremeka-nismen 30, medens en styrekant 60 på det første tætningselement 58 i en anden stilling af ventilstemplet 22 frigiver forbindelsen mellem trykkanalen 20 og trykkanalen 26, således at den hydrostatiske styremekanisme kan påvirkes med trykmedium. Det andet tætningselement 62 ligger mellem afløbskanalen 34 og afløbskanalen 36. I den første stilling af ventilstemplet 22 er afløbskanalen 34 ved hjælp af det andet tætningselement 62 afspærret fra afløbskanalen 36, medens en nederste styrekant 64 på tætningselementet 62 i den anden stilling af ventilstemplet 22 frigiver forbindelsen mellem afløbskanalen 34 og afløbskanalen 36. Det tredje tætnings-, element 66, som er anbragt ved den øverste ende af ventilstemplet 22, danner tæthed mellem afløbskanalen 36 og trykrummet 52. Kun den i dæmpningspladen 48 udformede drøvleåbning 50 gør det muligt, at der kan passere trykmedium fra den aksiale boring 44 ind i trykrummet 52. I den første stilling ligger det første tætningselement an mod et elastisk tætningsorgan 68, medens det andet tætningselement 62 ligger an mod et elastisk tætningsorgan 70. I området ved afløbskanalen 36 har ventilstemplet 22 en styrekant 72, som sammen med en anden styrekant 74 danner en drøvleanordning, hvis virksomme gennemstrømningstværsnit er foranderlig ved indstilling af ventilstemplet 22. På denne måde er det muligt.at holde den fra den aksiale boring 44 udstrømmende trykmediummængde konstant, således at styremekanismen hele tiden har en konstant trykmediummængde til rådighed, I afløbskanalen 36 findes desuden et indstilleligt drøvleorgan 76, ved hjælp af hvilket ventilblokken 18 kan tilpasses til styremekanismen 30.The valve piston 22 has three sealing elements 58, 62 and 66, of which the first sealing element 58 is disposed between the drain channel 34 and the hydraulic line 16 and thereby in a first position of the valve stem 22 separates the pressure channel 20 from the pressure channel 26 to the control mechanism 30, while a guide edge 60 on the first sealing member 58 in a second position of the valve piston 22 releases the connection between the pressure channel 20 and the pressure channel 26 so that the hydrostatic control mechanism can be actuated by pressure medium. The second sealing member 62 lies between the drain channel 34 and the drain channel 36. In the first position of the valve piston 22, the drain channel 34 is blocked by the second sealing element 62 from the drain channel 36, while a lower control edge 64 of the sealing element 62 in the second position of the valve piston 22 releases. the connection between the drain channel 34 and the drain channel 36. The third sealing element 66, which is located at the upper end of the valve piston 22, forms a tightness between the drain channel 36 and the pressure chamber 52. Only the throttle opening 50 formed in the damping plate 48 allows can pass pressure medium from the axial bore 44 into the pressure chamber 52. In the first position, the first sealing member abuts against an elastic sealing member 68, while the second sealing member 62 abuts on an elastic sealing member 70. In the region of the discharge channel 36, the valve piston 22 has a guide edge 72 which together with another guide edge 74 forms a throttle device if operable flow cross section is variable by adjusting the valve piston 22. In this way it is possible to keep the pressure medium flowing from the axial bore 44 constant so that the control mechanism always has a constant pressure medium quantity available, in the drain channel 36 there is furthermore an adjustable throttle member 76, by means of which the valve block 18 can be adapted to the control mechanism 30.
Til afløbskanalen 34 er tilsluttet endnu en hydraulikledning 78, som er forbundet med en trykbeholder 80. Trykbeholderen 80 optager differens-trykoliemængden for en til den hydrostatiske styremekanisme 30 tilsluttet styrecylinder 82, som over hydraulikledninger 84 og 86 er forbundet med styremekanismen 30. Mellem de to hydraulikledninger 84 og 86 findes to trykbegrænsningsventiler 88 og 90, som over en hydraulikledning 92 er forbundet med trykbeholderen 80. Den side af den hydrostatiske styremekanisme 30, som er forbundet med hydraulikpumpen 10, danner primærkredsen, medens den side af styremekanismen 30, som er forbundet med styrecylinderen 82, danner sekundærkredsen.To the drain channel 34 is connected another hydraulic line 78, which is connected to a pressure vessel 80. The pressure vessel 80 receives the differential pressure oil quantity of a control cylinder 82 connected to the hydrostatic control mechanism 30, which is connected via the hydraulic lines 84 and 86 to the control mechanism 30. Between the two hydraulic lines 84 and 86 are two pressure limiting valves 88 and 90 connected via a hydraulic line 92 to the pressure vessel 80. The side of the hydrostatic control mechanism 30 connected to the hydraulic pump 10 forms the primary circuit, while the side of the control mechanism 30 connected with the control cylinder 82, the secondary circuit forms.
Claims (5)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19732319135 DE2319135C3 (en) | 1973-04-16 | 1973-04-16 | Switching valve of a pressure medium supply device for a hydrostatic power steering for vehicles |
| DE2319135 | 1973-04-16 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| DK142353B true DK142353B (en) | 1980-10-20 |
| DK142353C DK142353C (en) | 1981-03-30 |
Family
ID=5878240
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DK177374A DK142353C (en) | 1973-04-16 | 1974-03-29 | STEERING MECHANISM FOR MOTOR VEHICLES |
Country Status (4)
| Country | Link |
|---|---|
| DE (1) | DE2319135C3 (en) |
| DK (1) | DK142353C (en) |
| FR (1) | FR2225326B1 (en) |
| GB (1) | GB1422485A (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1564108A (en) * | 1975-12-04 | 1980-04-02 | Massey Ferguson Perkins Ltd | Steering systems |
| DE2643312C2 (en) * | 1976-09-25 | 1983-01-13 | Deere & Co., Moline, Ill., US, Niederlassung Deere & Co. European Office, 6800 Mannheim | Electrical switching device for a directional valve |
| US4076096A (en) * | 1976-11-24 | 1978-02-28 | Clark Equipment Company | Hydraulic steering system |
| DE3006509C2 (en) * | 1980-02-21 | 1984-10-25 | Danfoss A/S, Nordborg | Hydrostatic steering device |
| DE3205411C2 (en) * | 1982-02-16 | 1984-02-02 | Danfoss A/S, 6430 Nordborg | Ventilation device for a hydraulic system |
| DE3233551C2 (en) * | 1982-09-10 | 1985-02-28 | Danfoss A/S, Nordborg | Device for detecting the gas content in a pressurized liquid system |
| EP3466806B1 (en) | 2017-10-09 | 2021-07-28 | MT-Propeller Entwicklung GmbH | Controllable pitch propeller unit with hydraulic control device |
-
1973
- 1973-04-16 DE DE19732319135 patent/DE2319135C3/en not_active Expired
-
1974
- 1974-03-25 FR FR7410058A patent/FR2225326B1/fr not_active Expired
- 1974-03-29 DK DK177374A patent/DK142353C/en active
- 1974-04-16 GB GB1658074A patent/GB1422485A/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| GB1422485A (en) | 1976-01-28 |
| FR2225326A1 (en) | 1974-11-08 |
| DE2319135A1 (en) | 1974-10-24 |
| DE2319135B2 (en) | 1980-01-10 |
| FR2225326B1 (en) | 1976-12-17 |
| DE2319135C3 (en) | 1980-09-11 |
| DK142353C (en) | 1981-03-30 |
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