US3828179A - Hydraulic system for automatically adjusting the positions of headlights of an automobile - Google Patents

Hydraulic system for automatically adjusting the positions of headlights of an automobile Download PDF

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Publication number
US3828179A
US3828179A US00337108A US33710873A US3828179A US 3828179 A US3828179 A US 3828179A US 00337108 A US00337108 A US 00337108A US 33710873 A US33710873 A US 33710873A US 3828179 A US3828179 A US 3828179A
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United States
Prior art keywords
hydraulic
cylinder
valve
work space
working
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Expired - Lifetime
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US00337108A
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English (en)
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S Straub
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Robert Bosch GmbH
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Robert Bosch GmbH
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60QARRANGEMENT OF SIGNALLING OR LIGHTING DEVICES, THE MOUNTING OR SUPPORTING THEREOF OR CIRCUITS THEREFOR, FOR VEHICLES IN GENERAL
    • B60Q1/00Arrangement of optical signalling or lighting devices, the mounting or supporting thereof or circuits therefor
    • B60Q1/02Arrangement of optical signalling or lighting devices, the mounting or supporting thereof or circuits therefor the devices being primarily intended to illuminate the way ahead or to illuminate other areas of way or environments
    • B60Q1/04Arrangement of optical signalling or lighting devices, the mounting or supporting thereof or circuits therefor the devices being primarily intended to illuminate the way ahead or to illuminate other areas of way or environments the devices being headlights
    • B60Q1/06Arrangement of optical signalling or lighting devices, the mounting or supporting thereof or circuits therefor the devices being primarily intended to illuminate the way ahead or to illuminate other areas of way or environments the devices being headlights adjustable, e.g. remotely-controlled from inside vehicle
    • B60Q1/08Arrangement of optical signalling or lighting devices, the mounting or supporting thereof or circuits therefor the devices being primarily intended to illuminate the way ahead or to illuminate other areas of way or environments the devices being headlights adjustable, e.g. remotely-controlled from inside vehicle automatically
    • B60Q1/10Arrangement of optical signalling or lighting devices, the mounting or supporting thereof or circuits therefor the devices being primarily intended to illuminate the way ahead or to illuminate other areas of way or environments the devices being headlights adjustable, e.g. remotely-controlled from inside vehicle automatically due to vehicle inclination, e.g. due to load distribution
    • B60Q1/105Arrangement of optical signalling or lighting devices, the mounting or supporting thereof or circuits therefor the devices being primarily intended to illuminate the way ahead or to illuminate other areas of way or environments the devices being headlights adjustable, e.g. remotely-controlled from inside vehicle automatically due to vehicle inclination, e.g. due to load distribution by fluid means
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B7/00Systems in which the movement produced is definitely related to the output of a volumetric pump; Telemotors
    • F15B7/001With multiple inputs, e.g. for dual control
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B7/00Systems in which the movement produced is definitely related to the output of a volumetric pump; Telemotors
    • F15B7/003Systems in which the movement produced is definitely related to the output of a volumetric pump; Telemotors with multiple outputs
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B7/00Systems in which the movement produced is definitely related to the output of a volumetric pump; Telemotors
    • F15B7/005With rotary or crank input
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B7/00Systems in which the movement produced is definitely related to the output of a volumetric pump; Telemotors
    • F15B7/008Systems in which the movement produced is definitely related to the output of a volumetric pump; Telemotors with rotary output

Definitions

  • the hydraulic system includes two component hydraulic systems, the first of which is provided with a mechanical linkage structure associated with spring-suspended parts at the front and rear of the automobile, two measuring cylinders having pistons displaceable therein and connected to the linkage structure, and a conduit which connects the two measuring cylinders with one another and with the work space of a common working cylinder of the hydraulic system.
  • the second component system is provided with a second working cylinder having a piston displaceable therein and a work space which is connected by a conduit to the common working cylinder, as well as a pair of headlight position adjusting linkages connected to the pistons of the two working cylinders on the one hand and adapted for mechanical connection to pivotably mounted headlights of the automobile, on the other hand.
  • This hydraulic system is improved by providing it with a fill-up valve in one, and a vent valve in the other of the component systems, and with a hydraulic conduit interconnecting the two systems in which conduit there is interposed a shut-off structure which can be opened in the direction of liquid flow from the fill-up valve to the vent valve, while the entire hydraulic system is being filled.
  • SHEET 2 [IF 2 HYDRAULIC SYSTEM FOR AUTOMATICALLY ADJ USTING THE POSITIONS OF HEADLIGHTS OF AN AUTOMOBILE BACKGROUND OF THE INVENTION
  • This invention relates to a hydraulic system for automatically adjusting the positions of headlights of an automobile, and is of the type comprising two hydraulic component systems, each of which is closed upon itself during operation, and of which component systems one serves as the actuating and the other as the responsive" system; common to both systems is a first working cylinder housing a piston displaceably and sealingly therein, which piston separates a first and a second work chamber in the said cylinder from'one another.
  • This hydraulic system further comprises in the first component system thereof mechanical motiontransmitting means which are associated with preferably spring-suspended, movable elements at the front part of the vehicle, and other such motion-transmitting means associated with similar movable elements at the rear part of the vehicle; these motion-transmitting means are actuated by the movements of the respective spring-suspended elements, for instance, the front and the rear axle, respectively, of the automobile, and are connected each to a piston displaceably housed in a measuring cylinder, while both these measuring cylinders are connected with one another and with one of the two work spaces, pertaining to this component system, of the aforesaid first working cylinder.
  • mechanical motiontransmitting means which are associated with preferably spring-suspended, movable elements at the front part of the vehicle, and other such motion-transmitting means associated with similar movable elements at the rear part of the vehicle; these motion-transmitting means are actuated by the movements of the respective spring-suspended elements, for instance, the
  • the other work space of the first working cylinder is connected via additional hydraulic conduit means to the work space of a second working cylinder having a second work piston housed sealingly therein, which second work piston is displaceable against the force of a return spring.
  • the work pistons of the first and second working cylinders are connected by means of mechanical headlight position-adjusting linkage means each with a pivotably mounted headlight of the automobile.
  • the total volume of hydraulic liquid in the work spaces of the two measuring cylinders will only change when the suspended front and rear elements of the automobile carry out movements relative to each other in an opposite sense, whereby the said total volume is either decreased or increased.
  • the hydraulic liquid forced out of the measuring cylinders serves to displace the work piston in the said first working cylinder and thereby cause this piston to shift the position-adjusting mechanical means to adjust the position of the headlight associated therewith, and force hydraulic liquid in the second component system out of the work space of the first working cylinder pertaining thereto into the work space of the second working cylinder, causing displacement of the piston therein which is transmitted via the position-adjusting mechanical means to the other headlight which is associated with the latter means.
  • the work spaces in the measuring cylinders and in the working cylinders must be sealed fluid-tight from the pistons; this is preferably achieved by means of sealing membranes.
  • This object is attained by providing one of the two component systems described with a single fill-up valve and the other component system with a single venting valve, and by linking both component systems by way of hydraulic connecting conduit means which are equipped with shut-off means for interrupting the flow of hydraulic liquid therethrough.
  • both component parts of the improved system according to the invention although being in operation closed each upon itself, can be filled together by means of a single fill-up valve and vented by means of a single further valve.
  • the shut-off means in the connecting conduit means between the two systems must be opened.
  • the connecting conduit means are located outside the first working cylinder and preferably connect the two work spaces in the latter cylinder with one another, spring-biassed check valve means being interposed in the said connecting conduit means, which check valve means open in the direction of liquid flow from the fill-up valve in one of the two component systems to the vent valve in the other component system.
  • the closing force of the return spring biassing the check valve is greater than the frictional forces occurring at the mechanical motion-transmitting linkage means associated with the headlights. It is an advantage of this feature that the check valve in the component systemconnecting conduit means can only be opened by the filling pressure of the hydraulic liquid, and that there can be no passage of hydraulic liquid from one component system to the other during operation.
  • the check valve in the connecting conduit means can be replaced by an externally actuable gate valve or the like.
  • the connecting conduit means consist in a stepped axial bore through the piston of the first working cylinder, wherein a wider diameter portion of the axial bore houses a spring-biassed check valve which opens in the direction of flow of the hydraulic liquid during filling from the fill-up valve in the one component system to the vent valve in the other component system.
  • This check valve preferably has its seat at a shoulder between the wider bore portion and an adjoining narrower bore portion, and may be provided with adjustable abutment means for the spring of the check valve in the said axial bore, whereby the bias of the spring can be varied.
  • This embodiment has the advantage of making separate connecting conduit means between the two component systems outside the first working cylinder superfluous, thus eliminating the need for further connecting points requiring sealing means and the risk of leakage of hydraulic fuel caused thereby.
  • FIG. 1 shows in a highly schematical view a hydraulic system, according to the invention, for automatically adjusting the position of the headlights of an automobile, which system comprises a first embodiment of the first working cylinder thereof;
  • FIG. 2 shows in a schematical partially sectional view another embodiment of the first working cylinder of the system.
  • FIG. 3 shows in a similar view a third embodiment of the first work cylinder of the same system.
  • the relative movement of the front and rear axles of an automobile in relation to the automobile body is transmitted from the front axle suspension 1 and rear axle suspension 2 via mechanical linkage means 3 and 4, respectively, to a measuring cylinder 5 associated with the front axle and to a measuring cylinder 6 associated with the rear axle.
  • the two measuring cylinders are of identical construction.
  • Each of measuring cylinders 5 and 6 houses a piston 8, 8' which contacts a flexible membrane 9, 9 which latter encloses together with the one end portion of the measuring cylinder 5,6 a work space 10,10.
  • a displacement of the piston 8,8 in the cylinder 5,6 is effected by means of the linkage means 3,4 actuating a lever 11,11 which acts by means of a spring-supporting disc 12, 12' and a spring 13,13 on the piston 8,8, thereby guaranteeing a shock-free transmission of forces.
  • the chambers 10,10 are connected with one another via a hydraulic conduit 14.
  • a further hydraulic conduit 15 leads from the measuring cylinder 5 via a throttle means 16 to a double-work space cylinder 18.
  • a piston 19 which divides the interior of this cylinder into a rear work space 20 and a front work space 21.
  • These work spaces 20 and 21 are sealed against the piston 19 by means of flexible membranes 22 and 23, respectively, which are clamped in between flanges 24 and 25, respectively, of the double-work space cylinder 18.
  • Piston 19 is connected by means of positionadjusting linkage means 28 to a car headlight 29 which is mounted for swivelling about a pivot 30.
  • the work spaces 20 and 21 are connected with one another by a bypass conduit 32 in which there is located a check valve 33 which is held on its valve seat by means of return spring 34.
  • a hydraulic connecting line 35 leads from the work space 21 of the double work-space cylinder 18 to the sole work space 42 of another work cylinder 36 which houses a piston 37 which adjusts the position of a second headlight 39 mounted on a pivot 30 by means of adjusting linkage means 38.
  • the piston 37 is separated from the work space 42 by means of a membrane 41 which is clamped in between flange means 40 of the cylinder 36.
  • the frontal face of the piston 37 turned away from the work space'42 in work cylinder 36 is acted upon by a spring 43 housed in the work cylinder 36.
  • the work space 42 can be ventilated by means of a vent valve 44.
  • the work space 10' of measuring cylinder 6 can be filled with hydraulic liquid by means of fill-up valve 45.
  • the volumes of work spaces 10 and 10 in measuring cylinders 5 and 6 will be altered in an opposite sense, eg when moving the lefthand axle ends of the front axle and the rear axle toward one another in a left turn of the automobile, piston 8 will be moved into cylinder 5 while piston 8' will be moved in a direction out of cylinder 6.
  • a pressure balance in work spaces 10 and 10 is achieved via conduit 14. If, however, the degrees of turn-in of the front axle and of the rear axle are different, then a change in the total volume made up of the sums of the volumes of work spaces 10 and 10 will be the result.
  • Hydraulic liquid is filled into the system by way of the fill-up valve 45 provided at measuring cylinder 6.
  • the vent valve 44 provided at the second work cylinder 36 Prior to filling in the liquid, the vent valve 44 provided at the second work cylinder 36 must be opened, and both headlights 29 and 39adjusted to and set in their prescribed positions.
  • the filling pressure of the liquid to be filled in must be sufficiently high to overcome the force of spring 34 acting on the check valve 33.
  • liquid will flow through valve 45 into the measuring cylinder 6, from there via hydraulic conduit 14 to measuring cylinder 5 and on to work space 20 of first work cylinder 18 via hydraulic conduit 15, from where it will flow via bypass conduit 32, and by opening check valve 33 into work space 21 and through connecting line 35 into the cylinder 36 from where it will leave the system via vent valve 44. Filling is terminated when no more gas is found to leave vent valve 44, whereupon both valves 44 and 45 will be closed.
  • FIG. 2 shows a second embodiment of the first, double work-space, working cylinder 18, wherein the check valve 33 in bypass conduit 32, shown in FIG. 1, has been replaced by an externally actuable gate valve 48.
  • This valve permits to separate the two partial hydraulic systems present on opposite frontal faces of work piston 19 in an unobjectionable manner.
  • the operation of the system having this second embodiment of the double-space working cylinder 18 is the same; however, when filling the system, it is necessary to first open the gate valve 48 and to close the same after the filling is terminated.
  • this valve 48 it is also possible to effect a later adjustment of the basic positions of the headlights 29 and 39 by opening the valve 48, shifting the headlights to their desired corrected position and then closing valve 48 again.
  • Such subsequent adjustment of the basic position of the headlights is only possible in the system as shown in FIG. 1 by a forced shifting of pistons 19 and 37, whereby check valve 33 is forced to open.
  • FIG. 3 shows yet another embodiment of the first, double work-space, working cylinder 18 housing a piston 19' which has a stepped axial bore consisting of a narrower bore portion 50 opening out of membrane 22 into work space 20 of cylinder 18, and a wider diameter bore portion 51 opening out of membrane 23 into work space 21 of the cylinder 18.
  • This axial bore 50, 51 replaces the bypass conduit 32 connecting work spaces 20 and 21 in the. embodiment of the working cylinder 18 shown in FIG. 1.
  • a check valve 33 biassed by a spring 34 against the annular shoulder 52 between the wider and narrower bore section acting as a valve seat.
  • the closing force of spring 34' is adjustable by means of a spring supporting abutment member 53 having an axial bore therethrough, which is set or screwed into the bore section 51 and the position of which in the axial bore portion 51 can be varied.
  • the above-described hydraulic system for automatically adjusting the positions and in particular the angle of inclination of the headlights of an automobile permits a re-filling with hydraulic fuel and a re-setting of 65 work that may have caused a shift in the position of the headlights.
  • said first component system comprises a. first mechanical linkage means adapted for being associated with a spring-suspended front part of the automobile,
  • second mechanical linkage means adapted for being associated with a spring-suspended rear part of the automobile, both saidfirst and second mechanical linkage means being responsive to a movement of said suspended front and rear parts relative to one another in an opposite sense;
  • hydraulic conduit means connecting said first measuring cylinder and said second measuring cylinder with one another and with said first work space in said first working cylinder;
  • said second component system comprises f. a second working cylinder, a second working piston displaceably and sealingly housed therein and defining a work space in said second working cylinder, and spring means for biassing said second working piston,
  • hydraulic conduit means connecting said second work space in said first working cylinder with said work space in said second working cylinder
  • a pair of headlight-position adjusting means adapted to be connected to a pair of pivotably mounted headlights of the automobile and one of said pair of adjusting means being connected to said first working piston and the other to said second working piston, the improvement comprising i. a fill-up valve for hydraulic liquid in one of said component systems, ii. a vent valve in the other component system,
  • shut-off means located in said hydraulic interconnecting conduit means for closing said interconnecting conduit means during a headlight adjustment operation and opening said interconnecting conduit means during a filling operation for said system.
  • shut-off means is a spring-biassed check-valve adapted for opening in the direction of liquid flow from said fill-up valve to said vent valve.
  • check valve comprises a return spring the closing force of which is greater than the sum of the frictional forces acting on said first and said second working piston during a displacement of liquid in said hydraulic system.
  • shut-off means is a gate valve
  • said hydraulic interconnecting conduit means comprise a stepped axial bore through said first working piston and wherein said shut-off means is a spring-biassed check valve located in said axial bore, and adapted for opening in the direction of liquid-flow from said fill-up valve to said vent valve.
  • check valve comprises return spring means biassing said check valve and spring-bias adjusting means displaceably associated with said return spring means in said axial bore.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • General Engineering & Computer Science (AREA)
  • Lighting Device Outwards From Vehicle And Optical Signal (AREA)
US00337108A 1972-03-14 1973-03-01 Hydraulic system for automatically adjusting the positions of headlights of an automobile Expired - Lifetime US3828179A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE2212131A DE2212131C2 (de) 1972-03-14 1972-03-14 Hydraulische Einrichtung zum selbsttätigen Regeln der Scheinwerferneigung bei Kraftfahrzeugen

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US3828179A true US3828179A (en) 1974-08-06

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US00337108A Expired - Lifetime US3828179A (en) 1972-03-14 1973-03-01 Hydraulic system for automatically adjusting the positions of headlights of an automobile

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US (1) US3828179A (enrdf_load_stackoverflow)
JP (1) JPS5614493B2 (enrdf_load_stackoverflow)
AT (1) AT322383B (enrdf_load_stackoverflow)
CH (1) CH552487A (enrdf_load_stackoverflow)
DE (1) DE2212131C2 (enrdf_load_stackoverflow)
FR (1) FR2176427A5 (enrdf_load_stackoverflow)
GB (1) GB1422166A (enrdf_load_stackoverflow)
IT (1) IT981372B (enrdf_load_stackoverflow)
NL (1) NL7303501A (enrdf_load_stackoverflow)
SE (1) SE380484B (enrdf_load_stackoverflow)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3947680A (en) * 1973-08-06 1976-03-30 Societe Anonyme Automobiles Citroen Steering responsive control device for turning automotive headlamps
US3955173A (en) * 1974-03-08 1976-05-04 The Lucas Electrical Company Limited Motor vehicle with headlamp tilting mechanism
US4004142A (en) * 1973-09-24 1977-01-18 Saab-Scania Aktiebolag Device for regulating the adjustment of vehicle headlights
US4180848A (en) * 1976-11-27 1979-12-25 Robert Bosch Gmbh Hydraulic apparatus for the automatic correction of the inclination of the headlights of a motor vehicle

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108583416B (zh) * 2018-01-27 2021-09-21 中山同鑫金属制品有限公司 车辆的车灯装置

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1748769A (en) * 1928-03-24 1930-02-25 Holliday Life Saving Headlight Dirigible headlight
US3402287A (en) * 1965-11-05 1968-09-17 Roy E Mcafee Load compensating headlight adjusting mechanism
US3453424A (en) * 1965-12-14 1969-07-01 Cibie Projecteurs Arrangement for the automatic reculation of the orientation of the headlamps of a vehicle

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1748769A (en) * 1928-03-24 1930-02-25 Holliday Life Saving Headlight Dirigible headlight
US3402287A (en) * 1965-11-05 1968-09-17 Roy E Mcafee Load compensating headlight adjusting mechanism
US3453424A (en) * 1965-12-14 1969-07-01 Cibie Projecteurs Arrangement for the automatic reculation of the orientation of the headlamps of a vehicle

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3947680A (en) * 1973-08-06 1976-03-30 Societe Anonyme Automobiles Citroen Steering responsive control device for turning automotive headlamps
US4004142A (en) * 1973-09-24 1977-01-18 Saab-Scania Aktiebolag Device for regulating the adjustment of vehicle headlights
US3955173A (en) * 1974-03-08 1976-05-04 The Lucas Electrical Company Limited Motor vehicle with headlamp tilting mechanism
US4180848A (en) * 1976-11-27 1979-12-25 Robert Bosch Gmbh Hydraulic apparatus for the automatic correction of the inclination of the headlights of a motor vehicle

Also Published As

Publication number Publication date
DE2212131A1 (de) 1973-09-20
DE2212131C2 (de) 1982-03-18
AT322383B (de) 1975-05-26
GB1422166A (en) 1976-01-21
IT981372B (it) 1974-10-10
FR2176427A5 (enrdf_load_stackoverflow) 1973-10-26
SE380484B (sv) 1975-11-10
NL7303501A (enrdf_load_stackoverflow) 1973-09-18
CH552487A (de) 1974-08-15
JPS5614493B2 (enrdf_load_stackoverflow) 1981-04-04
JPS49939A (enrdf_load_stackoverflow) 1974-01-07

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