DK9400327U3

DK9400327U3 - Steering mechanism for a vehicle

Info

Publication number: DK9400327U3
Application number: DK9400327U
Authority: DK
Inventors: Ole Hoejvang Andreasen
Original assignee: Ole Hoejvang Andreasen
Priority date: 1994-08-26
Filing date: 1994-08-26
Publication date: 1995-11-26

Description

DK 94 00327 U3DK 94 00327 U3

STYRINGSMEKANISME TIL ET KØRETØJSTEERING MECHANISM FOR A VEHICLE

Teknikkens standpunkt 5State of the art 5

Frembringelsen angår en styringsmekanisme til et køretøj af den art, der er angivet i krav l's indledende del.The invention relates to a steering mechanism for a vehicle of the kind specified in the preamble of claim 1.

For flerakslede køretøjer kan det under visse forhold være 10 en fordel at forsyne mere end én aksel med en styring. Eksempelvis vil der i forbindelse med fireakslede lastbiler med styring på forhjulet være et behov for at foretage en modsat styring på den bageste aksel for dermed at mindske den uønskede friktion, der opstår, når de bageste hjulpar 15 under drejning af lastbilen bliver flyttet vinkelret på hjulenes retning, da disse forhold medfører slitage på dæk og generelt generer eller umuliggør den nødvendige styring af lastbilen. Imidlertid er det ikke hensigtsmæssigt at foretage en styring på lastbilens bagaksel ved højere hastig-20 heder, da dette ved høj hastighed kan give anledning til en fatal overstyring.For multi-axle vehicles, it may be advantageous to provide more than one axle with a steering under certain conditions. For example, in the case of four-axle trucks with front-wheel steering, there will be a need to perform an opposite steering on the rear axle so as to reduce the unwanted friction that occurs when the rear wheel pairs 15 while turning the truck are moved perpendicular to the wheels. direction, as these conditions cause tire wear and generally generate or render necessary the necessary control of the truck. However, it is not appropriate to control the rear axle of the truck at higher speeds, as this can cause a fatal oversteer at high speed.

Det er fra DE 34 43 102 Al kendt at foretage en styring på bagakslen af et køretøj, der er modsat rettet styringen på 25 køretøjets forhjul. Denne styring er hastighedsafhængig, således at baghjulene under en tærskelhastighed på eksempelvis 20 km/t styrer modsat forhjulene, men er fastlåst mekanisk over tærskelhastigheden. Styringen af baghjulene bliver tilvejebragt af et hydraulisk system, og den meka-30 niske fastholdelse er tilvejebragt af en pneumatisk fremdrevet stang, der går i indgreb med en låseanordning og dermed fastholder baghjulenes styremekanisme i en fremad-retning.It is known from DE 34 43 102 A1 to make a steering on the rear axle of a vehicle which is opposite to the steering on the 25 front wheel of the vehicle. This steering is speed dependent so that the rear wheels under a threshold speed of, for example, 20 km / h steer opposite the front wheels, but are mechanically locked above the threshold speed. The control of the rear wheels is provided by a hydraulic system and the mechanical retention is provided by a pneumatically propelled rod which engages a locking device and thus holds the steering mechanism of the rear wheels in a forward direction.

Styringsmekanismen er imidlertid kompliceret, blandt andet fordi mekanismen, der tilvejebringer den mekaniske fasthol- 35 2 DK 94 00327 U3 delse nødvendigvis må suppleres med en mekanisme, der tilvejebringer en opretning af det bageste hjulpar, før dette fastlåses. Dette komplicerer udførelsen af det hydrauliske system, og en direkte kobling mellem styringen af forakslen og bagakslen er ikke mulig.However, the steering mechanism is complicated, inter alia, because the mechanism which provides the mechanical restraint must necessarily be supplemented by a mechanism which provides for alignment of the rear wheel pair before it is locked. This complicates the design of the hydraulic system, and a direct coupling between the control of the front axle and the rear axle is not possible.

Fordele ved frembringelsenBenefits of production

Ved, som at angivet i krav 1, at lade styringsmekanismen bestå af aktive separate styreopretriingsmidler, der er forbundet til bagakslen og via kontrolmidlerne styret således, at bagakslen over en given hastighed eller et interval derover, ved hjælp af de separate' styreopretningsmidler, aktivt styres mod og fastholdes i en position, således at styreretningen er sammenfaldende me[d køretøjets længderetning, og at styreforbindelsesmidlerne ligeledes over den givne hastighed eller et interval derover er afkoblet eller kortsluttet af kontrolmidlerne mellem forakslen eller styredelen og bagakslen, opnås en sikker og stabil fastholdelse af bagakslens styreretning i en akse, der er sammenfaldende med køretøjets akse, når dette er fordret. Yderligere opnås at bagakslen på grund af de aktive separate sty-reopretningsmidler, selv styrer mod en ligevægtsposition u-den hjælp fra og i princippet uafhængigt af styreforbindelsesmidlerne. Dette muliggør en imeget simpel og sikker opbygning af styreopretningsmidler og styreforbindelsesmidler, da styringen af styringsforbihdelsesmidlerne og kontrolmidlerne simpelt kan udgøres af i henholdsvis en afbryder og en omskifter, der skiftevis afkobler styreopretningsmidlerne og styreforbindelsesmidlerne. Yderligere fordele opnås, idet det er muligt at skalere modstyringen af baghjulene med en given faktor, således a't styringen er optimeret til det enkelte køretøj.As stated in claim 1, to allow the steering mechanism to consist of active separate steering gear means connected to the rear axle and controlled via the control means such that the rear axle is actively controlled over a given speed or interval thereof by means of the separate steering gear means. toward and retained in a position such that the steering direction coincides with the vehicle's longitudinal direction and that the steering link means are also decoupled or short-circuited by the control means between the front axle or steering part and the rear axle, a secure and stable retention of the rear axle steering direction in an axis that coincides with the vehicle axis when required. Further, due to the active separate steering means, the rear axle is even steered toward an equilibrium position without the aid of and in principle independent of the steering linkage means. This allows for a very simple and secure construction of control rectifying means and control connecting means, since the control of the control connecting means and the control means can simply be constituted by a switch and a switch respectively, which decouple the control rectifying means and the control connecting means alternately. Further advantages are obtained in that it is possible to scale the counter-steering of the rear wheels by a given factor so that the steering is optimized for the individual vehicle.

Ved, som angivet i krav 2, at forsyne styringsmekanismen 3 DK 94 00327 U3 med midler til separat og hastighedsuafhængig samtidig afkobling af styreforbindelsesmidlerne og tilkobling af styreopretningsmidler, opnås en ikke-automatiseret tilstand, der under visse forhold er ønskelig. Således er det en fordel for en chauffør af et givet køretøj, blandt andet ved kørsel i bagudretningen, separat at kunne slå styringen af baghjulene fra.By providing, as stated in claim 2, the control mechanism 3 DK 94 00327 U3 with means for separately and speed-independent simultaneous decoupling of the control connecting means and coupling of control rectifying means, a non-automated condition is desired which is desirable under certain conditions. Thus, it is advantageous for a driver of a given vehicle, among other things when driving in the rear direction, to be able to switch off the steering of the rear wheels separately.

Ved, som angivet i krav 3, at anvende hydrauliske styreforbindelsesmidler, opnås en optimal kraftoverføring mellem foraksel og bagaksel, der er nem at kontrollere.By using hydraulic steering linkage means as specified in claim 3, an optimal power transmission between the front axle and the rear axle is easy to control.

Ved, som angivet i krav 4, at anvende pneumatiske kontrolmidler, opnås en sikker og effektiv udførelse af kontrolmidlerne.By using pneumatic control means, as stated in claim 4, a safe and effective design of the control means is achieved.

Ved, som angivet i krav 5, at lade styreopretningsmidlerne bestå af to pneumatisk aktiverbare styrecylindre, hvilke styrecylindre hver består af en cylinder og et stempel definerende henholdsvis trykcylinderens cylinder- og stempelside, hvor cylindersiderne er koblet til køretøjet og stempelsiderne er koblet til den styrbare bagaksel, således at stemplernes bevægelseskomposanter under ens aktivering i hovedsagen er modsatrettede, opnås en udførelsesform, der er billig og sikker. Styrecylindrene vil således ved aktivering tilvejebringe en sikker fastholdelse af styreretningen, men vil også være i stand til at drive bagakslen mod en ligeudretning.As stated in claim 5, the steering erection means consist of two pneumatically actuable steering cylinders, each steering cylinders each consisting of a cylinder and a piston defining the cylinder and piston side of the pressure cylinder, respectively, where the cylinder sides are connected to the vehicle and the piston sides are coupled to the steerable rear axle. so that during the actuation of the pistons, the movement components of the pistons are substantially opposite, an embodiment which is inexpensive and safe is obtained. Thus, the actuating cylinders, upon activation, provide a secure retention of the directional direction, but will also be able to drive the rear axle towards a straight alignment.

Ved, som angivet i krav 6, at lade styreopretningsmidlerne være koblet til den styrbare bagaksel via styrearme, opnås en god kraftoverførsel fra styreopretningsmidlerne til den styrbare bagaksel, samt en simpel udførelsesform, der er billig og nem at fabrikere og servicere.By as stated in claim 6, leaving the steering uprights coupled to the steerable rear axle via steering arms provides a good power transfer from the steering uprights to the steerable rear axle, as well as a simple embodiment that is inexpensive and easy to manufacture and service.

Ved, som angivet i krav 7, at lade kontrolmidlerne bestå af 4 DK 94 00327 en afbryder, en ventilomskifter og en hydraulikafbryder, hvor afbryderen og ventilomskifteren er forsynet med trykluft fra en trykluftbeholder, hvilken afbryder, der har en åben tilstand og en afbrudt tilstand, er forbundet med et hydraulisk stempel, hvorfra der i hydraulikafbryderens åbne tilstand tilvejebringes et hydraulisk tryk i en væsketryk-cylinder, der via to sikkerhedsarrangementer bestående af en parallelkoblet kugleventil og overtryksventil og en parallelkoblet kugleventil og overtryksventil videreføres henholdsvis til hydraulikledningerné, og hvilken ventilomskifter i en første position leder trykluft fra trykluftbeholderen via en trykluftledning til styrecylindrene, og i en anden position leder trykluft til en trykluftstyret hydraulikafbryder, hvilken hydraulikafbryder er parallelkoblet mellem hydraulikledningerne, og hvilken hydraulikafbryder i ventilomskifterens første position udgør en kortslutning mellem hydraulikledningerne o!g i ventilomskifterens anden position udgør en afbrydelse mellem' hydraulikledningerne, opnås en hensigtsmæssig udføfelsesform.As stated in claim 7, the control means comprise a switch, a valve switch and a hydraulic switch, the switch and the valve switch being provided with compressed air from a compressed air container, which switch has an open state and a disconnected state. , is connected to a hydraulic piston from which, in the open state of the hydraulic switch, a hydraulic pressure is provided in a fluid pressure cylinder which, via two safety arrangements consisting of a parallel coupled ball valve and pressure valve and a parallel coupled ball valve and pressure valve, is respectively passed to the hydraulic line switches and a first position conducts compressed air from the compressed air vessel via a compressed air line to the control cylinders, and in a second position compressed air leads to a compressed air controlled hydraulic switch, which hydraulic switch is connected in parallel between the hydraulic lines and which hydraulic switch in the first position of the valve switch constitutes a interconnection between the hydraulic lines and in the second position of the valve switch constitutes an interruption between the hydraulic lines, an appropriate embodiment is obtained.

Ved, som angivet i krav 8, at lade styreforbindelsesmidlerne og kontrolmidlerne blive gradvist indkoblet og aktiveret ved en hastighedsforøgelse, der passerer tærskelhastigheden, og/eller blive gradvist afkoblet ved en hastighedsformindskning, der ligeledes passerer tærskelhastigheden, opnås en mulighed for på en simpel måde at forsinke tidspunktet, hvorpå styringen af baghjulene bliver aktiveret som funktion af systemets forhistorie, specielt når køretøjet kommer fra en tilstand med en høj hastighed til en tilstand ved en lav hastighed, som det forekommer ved eksempelvis en nedbremsnincf. Dette medfører, at eri eventuel undvigemanøvre, foretaget ved en hastighed omkring overgangshastigheden ikke bliver forstyrret af en pludsølig indkobling af bag-hjulsstyrincjen, da systemet dermed har hukommelse.As stated in claim 8, allowing the control connecting means and control means to be gradually engaged and activated by a rate increase passing the threshold speed, and / or being gradually decoupled by a rate decrease also passing the threshold speed, a possibility is obtained in a simple manner to delay the time at which the control of the rear wheels is activated as a function of the system's history, especially when the vehicle comes from a state of high velocity to a state of low velocity, as occurs, for example, by a slowdown. This means that in any avoidance maneuver made at a speed around the transition speed is not disturbed by a sudden disengagement of the rear wheel steering wheel, since the system thus has memory.

5 DK 94 00327 U35 DK 94 00327 U3

Ved, som angivet i krav 9, at indføre en ventilspærre mellem ventilomskifteren og styrecylindrene, der gradvist kan afkobles ved en hastighedsformindskning over tærskelhastigheden, opnås en fordelagtig udførelsesform, der kompenserer 5 på en passende måde ved en simpel opbygning.As indicated in claim 9, introducing a valve lock between the valve switch and the control cylinders which can be gradually decoupled by a speed decrease over the threshold speed, an advantageous embodiment compensating 5 is obtained in a suitable manner by a simple construction.

Ved, som angivet i krav 10, at anvende separate styreopretningsmidler på styrbare baghjul i en kendt styringsmekanisme, hvilke styreopretningsmidler består af trykcylindre, 10 opnås en sikker og bedre styringsmekanisme. Således vil kendte styringsmekanismer kunne optimeres ved den angivne anvendelse af styreopretningsmidlerne.By using, as stated in claim 10, separate steering erection means on steerable rear wheels in a known steering mechanism, which steering erection means consist of pressure cylinders, 10 a safe and better steering mechanism is obtained. Thus, known control mechanisms can be optimized by the stated use of the control alignment means.

Tegningen 15Drawing 15

Et udførelseseksempel på frembringelsen vil blive nærmere beskrevet i det efterfølgende afsnit under henvisning til tegningen, hvor 20 fig. 1 viser en styringsmekanisme ifølge frembringel sen, fig. 2 viser lavhastighedstilstanden af styringsmekanismen ifølge frembringelsen, 25 fig. 3 viser højhastighedstilstanden af styringsmekanismen ifølge frembringelsen, og fig. 4 viser styringsmekanismen, når der ikke er tryk 30 på det hydrauliske system.An exemplary embodiment of the invention will be described in more detail in the following section with reference to the drawing, in which: FIG. 1 shows a control mechanism according to the invention; FIG. 2 shows the low speed state of the control mechanism according to the invention, FIG. 3 shows the high speed state of the control mechanism according to the invention, and FIG. 4 shows the control mechanism when there is no pressure 30 on the hydraulic system.

Beskrivelse af udførelseseksempletDescription of the embodiment

En udførelsesform ifølge frembringelsen ses på figur 1. Ud-35 førelseseksemplet består af en styring til en fireakslet lastvogn 1, der er forsynet med en foraksel 3, to aksler 4 6 DK 94 00327 U3 og 5, og en bagaksel 5, hvor akslen 5 er drivaksel. På akslerne er der monteret hjul 2.An embodiment according to the invention is shown in Figure 1. The embodiment consists of a control for a four-axle truck 1, which is provided with a front axle 3, two axles 4 6 and 94, and a rear axle 5, where the axle 5 is the drive shaft. On the shafts, wheels 2 are mounted.

Styringen af lastbilen 1 udføres ved i hjælp af et rat 7, der via en styrearm 8, en såkaldt pitman-arm, er forbundet med en styreforbindelse 9, der igen er forbundet med den ene ende af en styrearm 10. Styrearmen 10 er lejret til forakslen 3 i lejet 11. Den anden ende af styrearmen 10 er via et stempel 12 forbundet med en væske tryk cylinder 13. Fra væ-sketrykcylinderen 13 forløber to hydraulikledninger 14 og 15 til en hydraulikafbryder 22. Hydraulikledningerne er videreført fra hydraulikafbryderen 22 til en styrecylinder 16 med et stempel 17. Stemplet 17 er forbundet med en styrearm 18, der er lejret til bagakslen 6 i lejet 19. En styreforbindelse 20 forbinder styrearmen 18 med en styrearm 21.The control of the truck 1 is carried out by means of a steering wheel 7, which is connected via a control arm 8, a so-called pitman arm, to a control connection 9, which in turn is connected to one end of a control arm 10. The control arm 10 is mounted to the front axle 3 in the bearing 11. The other end of the control arm 10 is connected via a piston 12 to a fluid pressure cylinder 13. From the fluid pressure cylinder 13 two hydraulic lines 14 and 15 extend to a hydraulic switch 22. The hydraulic lines are passed from the hydraulic switch 22 to a control cylinder. 16 with a piston 17. The piston 17 is connected to a control arm 18 which is mounted to the rear axle 6 in the bearing 19. A control connection 20 connects the control arm 18 to a control arm 21.

Styringen omfatter yderligere en trykluftbeholder 29, der via af en trykluftledning er forbundet til en trykluftcylinder 31 med et stempel 30 gennem en afbryder 32, der via et væsketrykkabel 40 dels er ført vådere til hydraulikledningen 15 via en parallel forbundet kugleventil 33 og over-trykventil 35, og dels er ført videre til hydraulikledningen 14 via en parallelforbundet kugleventil 34 og overtrykventil 36.The control further comprises a compressed air container 29 connected via a compressed air line to a compressed air cylinder 31 with a piston 30 through a switch 32, which is supplied via a fluid pressure cable 40 partly to the hydraulic line 15 via a parallel connected ball valve 33 and overpressure valve 35 and partly passed to the hydraulic line 14 via a parallel-connected ball valve 34 and overpressure valve 36.

Trykluftbeholderen 29 er ligeledes forbundet med en ventilomskifter 23, hvorfra der forløber trykluftledninger til hydraulikafbryderen 22 og til to styrecylindre 24 og 25, der er forbundet til henholdsvis styrearmene 18 og 21 ved hjælp af stemplerne 26 og 27.The compressed air container 29 is also connected to a valve switch 23, from which compressed air lines to the hydraulic switch 22 and to two control cylinders 24 and 25 connected to the control arms 18 and 21 respectively by the pistons 26 and 27.

Selve styringen af lastbilens 1 styrbare bagaksel 6 foregår altså således, at den i rattet 7 tilførte mekaniske energi via væsketrykcylinderen 13 bliver overført af det hydrauliske system, der delvist består af hydraulikledningerne 14 7 DK 94 00327 U3 og 15, til bagakslens 6 styrecylinder 16. Hydraulikledningerne 14 og 15 er via stemplet 17 forbundet således til styrearmen 18, at den bageste aksel 6 styrer modsat den forreste aksel 3.The control of the steerable rear axle 6 of the truck 1 is thus carried out so that the mechanical energy supplied in the steering wheel 7 is transferred via the fluid pressure cylinder 13 by the hydraulic system, which consists partly of the hydraulic lines 14 7 to the steering cylinder 16 of the rear axle 6. The hydraulic lines 14 and 15 are connected via the piston 17 to the control arm 18 such that the rear axle 6 controls opposite to the front axle 3.

55

Det hydrauliske tryk i systemet bliver således tilvejebragt af væsketrykcylinderen 31 ved hjælp af trykluften leveret af trykluftbehdlderen 29, såfremt afbryderen 32 er åben.The hydraulic pressure in the system is thus provided by the liquid pressure cylinder 31 by means of the compressed air supplied by the compressed air reservoir 29, if the switch 32 is open.

10 Hydraulikafbryderen 22 er under normal kørsel med hastigheder over ca. 30 km/t kortsluttet mellem hydraulikledningerne 14 og 15, således at det hydrauliske system ikke styrer på baghjulene, mens hydraulikafbryderen 22 ved hastigheder under 30 km/t er afbrudt, således at det hydrauliske sy-15 stem styrer på baghjulene.10 The hydraulic switch 22 is in normal operation at speeds above approx. 30 km / h short-circuited between the hydraulic lines 14 and 15, so that the hydraulic system does not control the rear wheels, while the hydraulic switch 22 is switched off at speeds below 30 km / h, so that the hydraulic system controls the rear wheels.

Ventilomskifteren 23 styrer hydraulikafbryderen således, at den er kortsluttet, mens ventilomskifteren 23 leder trykluft til styrecylindrene 24 og 25, der dermed fastholder 20 baghjulene i en position, der er ensrettet med lastbilens længderetning. Dette medfører, at styrecylindrene 24 og 25 ikke skal tilvejebringe kræfter, der er modsat rettede eventuelle kræfter hidrørende fra det hydrauliske system. Det betyder således, at det hydrauliske styresystem på bag-25 hjulene er frakoblet ved højre hastigheder.The valve switch 23 controls the hydraulic switch so that it is short-circuited, while the valve switch 23 directs compressed air to the control cylinders 24 and 25, thus holding 20 the rear wheels in a position that is aligned with the longitudinal direction of the truck. This causes the control cylinders 24 and 25 not to provide forces that are opposite to any forces arising from the hydraulic system. This means that the hydraulic steering system on the rear wheels is disengaged at right speeds.

Ved hastigheder under ca. 30 km/t frakobles styrecylindrene 24 og 25, og styringen af baghjulene tilvejebringes af det hydrauliske system.At speeds below approx. At 30 km / h, the steering cylinders 24 and 25 are disengaged and the steering of the rear wheels is provided by the hydraulic system.

3030

Styringen af systemet er foretaget af et ikke vist elektronik kredsløb.The control of the system is made by an electronics circuit not shown.

På figur 2 til 4 vises en tilsvarende udførelsesform som 35 vist på figur 1 for et toakslet køretøj 1. På tegningerne fremgår specielt det pneumatiske system, der helt svarer 8 DK 94 00327 U3 til det på figur 1 viste. Det pneumatiske system vises i tre tilstande, hvor ventilomskifteren 23 er i position A' eller B’, afbryderen 32 er i position A eller B og hydraulikafbryderen 22 er i position A'' øller B''.Figures 2 to 4 show a similar embodiment as shown in Figure 1 for a two-axle vehicle 1. In the drawings, in particular, the pneumatic system, which corresponds completely to that shown in Figure 1, is shown. The pneumatic system is shown in three states where valve switch 23 is in position A 'or B', switch 32 is in position A or B and hydraulic switch 22 is in position A '' beers B ''.

5 På figur 2 er afbryderen 32 i position A, hvilket betyder at afbryderen er åben, og at der ledes trykluft til væske-trykcylinderen 31, og dermed tilvejebringer et tryk på det hydrauliske system. Ventilomskifterén 23 er i position B', 10 hvilket betyder, at der ledes trykluft til hydraulikafbryderen 22, hvilket igen medfører, at denne er afbrudt i position B'', og dermed ikke forbinder de to hydraulikledninger 14 og 15. Dette betyder, at der ikke tilføres lufttryk til styrecylindrene 24 og 25, og at det hydrauliske system 15 tilvejebringer en styring på baghjulene. Situationen vist på figur 2 forekommer i lave hastigheder under ca. 30 km/t.In Figure 2, the switch 32 is in position A, which means that the switch is open and that compressed air is fed to the fluid pressure cylinder 31, thus providing a pressure on the hydraulic system. The valve switch 23 is in position B ', 10 which means that compressed air is fed to the hydraulic switch 22, which in turn causes it to be switched off in position B' ', thus not connecting the two hydraulic lines 14 and 15. This means that air pressure is not applied to the steering cylinders 24 and 25 and the hydraulic system 15 provides a steering on the rear wheels. The situation shown in Figure 2 occurs at low speeds below approx. 30 km / h

På figur 3 er afbryderen 32 i position A, hvilket igen medfører, at der er tryk på det hydrauliske system. Ventilom-20 skifteren er i position A', hvilket medfører, at hydraulikafbryderen 22 er i hvilepositionen A'', og dermed er kortsluttet mellem hydraulikledningerne 14 og 15, hvilket medfører at det hydrauliske system ikke tilvejebringer en styring på baghjulene. Yderligere medfører ventilomskifterens 25 22 position A', at der bliver ledt trykluft til styrecy lindrene 24 og 25, hvilket medfører at baghjulene bliver fastholdt i en retning, der er parallel med køretøjets længdeakse. Situationen vist på figur 3 forekommer i hastigheder over ca. 30 km/t.In Figure 3, the switch 32 is in position A, which in turn causes pressure on the hydraulic system. The valve switch 20 is in position A ', which causes the hydraulic switch 22 to be in the resting position A' ', and thus is short-circuited between the hydraulic lines 14 and 15, which means that the hydraulic system does not provide a control on the rear wheels. In addition, position A 'of valve switch 25 22 causes compressed air to be guided to the steering cylinders 24 and 25, which causes the rear wheels to be held in a direction parallel to the longitudinal axis of the vehicle. The situation shown in Figure 3 occurs at speeds above approx. 30 km / h

30 På figur 4 ses afbryderen 32 i position B, hvilket medfører, at der ikke er tryk på det hydrauliske system. Ventilomskifteren 23 er i position A' og leder dermed trykluft 35 til styrecylindrene 24 og 25. Denne tilstand forekommer, når der ikke er tryk på det hydrauliske system, hvilket 9 DK 94 00327 U3 medfører, at baghjulene i en sådan tilstand er fastholdt i en fremadrettet position. Denne tilstand vil også være opstartstilstanden.30 Figure 4 shows the switch 32 in position B, which means that there is no pressure on the hydraulic system. The valve switch 23 is in position A 'and thus conducts compressed air 35 to the control cylinders 24 and 25. This condition occurs when there is no pressure on the hydraulic system, which causes the rear wheels in such a state to be held in a forward position. This mode will also be the boot mode.

Hvor der ikke er behov for en hastighedsstyret styringsmekanisme, kan denne udelades således, at den hydrauliske styring er konstant tilsluttet og dermed fungerer uafhængigt af køretøjets hastighed.Where no speed-controlled steering mechanism is required, this can be omitted so that the hydraulic steering is constantly connected and thus functions independently of the vehicle speed.

Claims

1. Steering mechanism for vehicles with two or more axles, of which the front axle and rear axle are controllable, said steering mechanism comprising a steering member, steering linkage and control means, which is connected to the steerable front axle and provides steering forces proportional to the steering direction. or the instantaneous differential fluctuation, such that the steering portion defines the steering axle's steering direction, which steering connecting means connects the steerable front axle or steering part to the steerable rear axle and thus provides a transfer of the aforementioned steering forces between the front axle or steering part and the steerable rear axle so that the steering of the rear axle a given threshold speed with a given factor is proportional, but opposite to the steering of the front axle and above a given threshold speed is either maintained in the longitudinal axis of the vehicle or by a given factor is proportional to the steering of the front axle, which control means could trolling and controlling the steering link means and thus the transfer of the steering forces between front axle or steering part and rear axle, which steering mechanism is new in that the steering mechanism further comprises active separate steering means connected to the rear axle and controlled via the control means such that a rear axle at a given speed or the interval thereof by means of the separate steering means is actively guided towards and retained in a position such that the steering direction coincides with the longitudinal direction of the vehicle, and that the steering means are likewise decoupled or shortened by the control means between the front axle or the steering part and the rear axle. .

The control mechanism according to claim 1, which is new in that the control mechanism is provided with means for separately and speed independent simultaneous decoupling of the control connection means and coupling of control rectifying means.

The control mechanism according to claim 1 or 2, which is new in that the control connecting means are hydraulic. 5

Control mechanism according to any one of the preceding claims 1 to 3, which is new in that the power transmission of the control means is carried out by means of compressed air.

Control mechanism according to any one of the preceding claims 1 to 4, which is new in that the control alignment means consist of two pneumatically actuable control cylinders (24) and (25), each of the control cylinders (24) and (25) each consisting of a cylinder and a piston defining, respectively, the cylinder and piston side of the pressure cylinder, where the cylinder sides are coupled to the vehicle and the piston sides are coupled to the steerable rear axle, so that during the actuation of the pistons the components of movement are substantially opposite.

Steering mechanism according to any one of the preceding claims 1 to 5, which is new in that the steering alignment means are coupled to the steerable rear axle via steering arms (18) and (21).

Control mechanism according to any one of the preceding claims 1 to 6, which is new in that the control means consist of a switch (32), a valve switch (23) and a hydraulic switch (22), wherein the switch (32) and the valve switch (23). ) is provided with compressed air from a compressed air container (29), which switch (32) having an open state (A) and a disconnected state 30 (B) is connected to a hydraulic piston (30) from which in the switch ( 32) open state, a hydraulic pressure is provided in a fluid pressure cylinder (31) which, via two safety arrangements consisting of a parallel coupled ball valve (33) and pressure valve (35) and a parallel coupled ball valve (34) and pressure valve (36), respectively are supplied to the hydraulic lines ( 15) and (16), which in a first position (A ') valve switch (23) conducts compressed air from the compressed air container (29) via a compressed air line (28) to the control cylinders (24) and (25) and in a second position (B ') conducts compressed air to a compressed air controlled hydraulic switch (22), which hydraulic switch (22) is connected in parallel between the hydraulic lines (15) and (16), and which hydraulic switch (22) in the first position of the valve switch (A1) is a short circuit between the hydraulic lines (15) and (16) ) and in the second position (B ') 10 of the valve switch (23) constitutes a disconnection between hydraulic lines (15) and (16).

Control mechanism according to any one of the preceding claims 1 to 7, which is new in that the control rectifying means and the control means are gradually switched on and activated by a speed increase above the threshold speed and / or gradually decoupled by a speed decrease over the threshold speed.

Control mechanism according to claim 8, which is new in that between a valve switch 23 and the control cylinders 24 and 25 there is inserted a valve lock which can be gradually switched off at a speed decrease over the threshold speed.

Use of separate steering gear means on steering wheel only rear wheels in a known steering mechanism, which steering gear means consists of pressure cylinders. 30