• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:

    公开号:SE1251114A1
    申请号:SE1251114
    申请日:2012-10-03
    公开日:2014-04-04
    发明作者:Frederik Laanen
    申请人:Scania Cv Ab；
    IPC主号:
    专利说明:

    15 20 25 30 2 RAS (Rear Axle Steering) by the manufacturer ZF. The construction is such that a so-called master cylinder is mounted in the front trailer and is controlled, according to a variant, physically by the sector gear of the power steering gear. Furthermore, the master cylinder is hydraulically coupled to a slave cylinder which is shaft mounted on the support shaft. To comply with EU legal requirements (70/311 / EEC or UN ECE R79) which deal with steering forces, the support shaft control system has a flow monitor in the main circuit that warns of low hydraulic oil flow. When the flow switch is activated, a so-called directional valve in the support shaft control circuit which hydraulically connects the right and left control chambers in the slave cylinder to facilitate the steering force test and to maintain the support shaft in the centered position as best as possible with the nominal pressure value of 14 bar in pressure. The system is essentially identical to that used for non-articulated buses with steered support shaft.
    The system described above works in such a way that when the driver turns the steering wheel to turn, for example, to the left, this will mean that the steered support axle is applied to a steering to the right to facilitate the turning of the vehicle. This is schematically illustrated in Figures 1a-1c which show an articulated vehicle during a reversing maneuver.
    Should you build an articulated bus with such a system, you will encounter problems when, for example, reversing or maneuvering in tight spaces as the support axle will steer in the wrong direction depending on how the driver has turned the steering wheel and how the articulation angle is.
    This will be described with reference to an example the detour backs up and wants to fold the trail to the left. The starting point is a position where the bus has zero at the joint angle so that the front and rear parts are in line with each other - see figure 1a. Initially, the driver turns the steering wheel a little to turn the wheels to the right to fold in the rear part to the left, whereupon reversing and folding begin. To "meet" the rear part, the driver will turn the steering wheel to the left and then steer the support shaft to the right due to the slave cylinder position as described above - see figure lb. So far, the effect of the steering is the intended one, but if the driver has to fold in the rear more (ie increase the articulation angle) for some reason (eg an obstacle or a narrow passage), the driver will turn the steering wheel to the right, which means that the support shaft steers to the left - see figure 1c. The consequence of this is that the rear part does not want to fold in more but actually wants to reduce the joint angle. The same phenomenon occurs when driving forward when the articulation angle and steering wheel angle are in different directions (eg the articulation turned to the left while the front wheels point to the right).
    The above examples show that the maneuverability of the vehicle decreases markedly and also increases the load on the joint. In addition, so-called grinding angles on the tires will be abnormally high, which leads to abnormal and unwanted tire wear.
    The object of the present invention is to obviate the above disadvantages in connection with the maneuvering of articulated vehicles, for example buses and lorries, with a steerable support shaft.
    SUMMARY OF THE INVENTION The above objects are achieved by the invention defined by the independent claims.
    Preferred embodiments are defined by the dependent claims.
    According to a preferred embodiment, the control system is adapted to activate a directional valve for the hydraulic system for the support shaft guide and thereby provide a centered support shaft when the articulation angle and the angle of the steering wheels (steering wheel angle) do not have the same direction.
    By applying the control system and the method according to the present invention, an increased passability of the vehicle is achieved, a reduced load on the support axle, which results in a reduced tire wear. Brief Description of the Drawings Figures 1a-1c schematically illustrate a reversing maneuver with an articulated vehicle according to the prior art.
    Figure 2 schematically illustrates the corresponding reversing maneuver with an articulated vehicle according to the present invention.
    Figure 3 schematically illustrates an articulated vehicle according to the present invention.
    Figure 4 is a schematic block diagram intended to illustrate the control system according to the present invention in connection with an articulated vehicle.
    Figure 5 is a flow chart illustrating the method of the present invention.
    DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION The present invention will now be described in detail with reference to the accompanying drawings. In the figures, the same or similar details have been denoted by the same reference numerals.
    Referring primarily to Figure 4, the invention relates to a control system 2 for an articulated vehicle 4, for example a bus or a truck. The vehicle comprises a front vehicle part 6 with a first longitudinal axis L1, and a rear vehicle part 8 with a second longitudinal axis L2. The vehicle parts are connected to each other via a joint 10 which enables the vehicle parts to be pivotable relative to each other, primarily in a horizontal plane. The vehicle further comprises a steering wheel axle 12 in the front vehicle part 6 and a steerable support axle 14 in the rear vehicle part 8. In the figures, further axles have been omitted to more clearly illustrate the invention. These can be located on both the rear and / or the front of the vehicle part. For example, the rear vehicle part may often comprise a drive axle located in front of the steerable support axle.
    The control system comprises a processing unit 16, a front control unit 18 adapted to output a first control signal 20 for controlling the wheels on the steering wheel shaft 12, a rear control unit 22 adapted to output a second control signal 24 for controlling the wheels on the steerable support shaft 14.
    According to the invention, the control system 2 further comprises a first measuring unit 26 adapted to determine the direction RV1 for an angle V1 of the wheels on the steering wheel axle 12 in relation to the forward direction of the L1 of the vehicle. See figure 3 where the angle V1 has been marked.
    According to one embodiment, the direction RV1 is determined so that RV1 = VR when the vehicle turns to the right and RV1 = VL when the vehicle turns to the left. Alternatively, you can define angular intervals when VR and VL are present, for example if V1 is between 0 and 45 degrees calculated clockwise in relation to L1 is RVK = VR, and when V1 is between 315 and 360 degrees calculated clockwise in relation to L1 is RVK = VL.
    The control system also comprises a second measuring unit 28 adapted to determine the direction RVK for an angle VK at the joint 10 between the first and second longitudinal axes (L1, L2). See figure 3 where the angle VK has been marked.
    The direction RVK for the angle VK at the joint between the first and second longitudinal axes (L1, L2) on the right side of the vehicle, in the forward direction of the vehicle, is preferably determined so that RVK = VR if VK is less than 180 degrees and RVK = VL if the angle is greater than at least 180 degrees. One can thus specify an interval around 180 degrees, for example +/- 5 degrees, within which the trail is allowed to vary before RVK is given the value VR or VL.
    The second measuring unit 28 can for instance be realized with a rearward-facing camera mounted on the front vehicle part on either side of the vehicle and compare the images with each other to obtain a measurement of the angle VK. Another alternative is to arrange an angle sensor in the pivot point of the joint.
    The first and second measuring units 26, 28 are adapted to output RV1 and RVK, respectively, to the processing unit 16 which is adapted to determine said second control signal 24 for the rear control unit 22 depending on at least RV1 and RVK so that if RV1 does not conform to RVK, the second The control signal 24 so that the controllable support shaft 14 is centered, i.e. the wheels on the support shaft are aligned to roll substantially parallel to L2. This is illustrated in Figure 2.
    According to one embodiment, the processing unit 16 is adapted to receive a gear position signal 30, containing information on the current gear of the vehicle, and that the processing unit 16 is adapted to take this into account when the second control signal 24 is determined. If, for example, the gear position signal 30 indicates that the vehicle intends to reverse, this may be a prerequisite for centering the steerable support shaft if the conditions regarding RV1 and RVK are met.
    In addition to the gear position signal, a speed signal 32 can also be applied to the processing unit 16. The speed signal indicates the speed of the vehicle and by comparing the current speed with a number of speed thresholds and depending on the result of the comparison affect the centering of the support shaft.
    According to a preferred embodiment, said front 18 and rear 22 control units consist of hydraulic units which are preferably interconnected. The rear control unit comprises a directional valve, the directional valve being adapted to be opened depending on the second control signal so that said support shaft is centered. This embodiment will be described in more detail below.
    According to a further embodiment, the front 18 and rear 22 control units are electronically controlled hydraulic, and preferably separate, units.
    In a vehicle, there are often several control systems that are adapted to monitor various parameter pre-vehicles, for example steering wheel angle, articulation angle and selected gear. In the above description, a first and a second measuring unit have been defined for measuring a value of the angles needed to practice the invention. It is of course also possible, within the scope of the inventive idea, that these measured values instead come from one or more control systems in the vehicle which in turn have obtained relevant measured values from different measuring units.
    According to the above-mentioned preferred embodiment, the invention is implemented by a hydraulically controlled support shaft arranged behind the driving shaft. The hydraulic control described here, and as described above, is used, for example, in the control of support axles for buses and is described, for example, in the European patent EP-1529717.
    This known control system consists of a master cylinder, a slave cylinder, a pressure accumulator, a pressure switch, a flow switch, a directional valve and a control lamp. The hydraulic pump used for power steering has a higher fl capacity in this application than on, for example, buses where the steering only takes place on the front axle.
    The master cylinder is located adjacent to the power steering gear and is connected directly, or via an intermediate steering arm, to the steering link arm for actuating the steering shaft.
    The slave cylinder is arranged in connection with the support shaft and affects its guide link arm.
    The master cylinder consists of four chambers. Two of the chambers communicate with the power steering gear and are pressurized when the power steering gear is actuated by the steering wheel. The other two chambers are connected to two chambers in the slave cylinder and transmit the steering force by hydraulic means to the wheels of the support shaft. During the first five degrees of wheel bearing on the front wheels, the steering angle of the support axle is not affected, in order to maintain good directional stability.
    The slave cylinder has a control part with two chambers and a centering part. When the hydraulic oil from the master cylinder pressurizes one of the chambers of the steering part, the piston rod will be actuated and transmit the force to the steering link arm.
    When the guide changes direction, the second chamber is pressurized and the piston rod is pushed in the other direction. When the steering angle of the front wheels is less than about five degrees, both steering chambers will be connected via a function in the master cylinder.
    In this position the centering part of the slave cylinder will become active and the oil in the centering part will have a pressure exceeding the pressure prevailing in one of the control chambers and thereby the piston rod will be kept still in the middle position, i.e. the support shaft is centered.
    In more detail, this is achieved in that the centering part consists of two pistons where one is attached to the piston rod and the other is a loose piston. In the centering part there is also a fixed partition wall. The system pressure of, for example, 14 bar acts on these pistons so that they will abut against the fixed partition and in this way keep the wheels in a straight-ahead position.
    The pressure accumulator absorbs pressure shocks in the system and maintains this pressure in the system, which means that the wheels of the support shaft strive towards the straight-ahead position when steering.
    If the hydraulic pressure in the system is too low, a pressure switch will switch on the control lamp on the instrument panel.
    In the control system there is a flow monitor that controls the directional valve. If the flow in the control system is below 5 liters / min, the flow monitor will electrically actuate the directional valve, at the same time the control lamp on the instrument panel lights up.
    In the hydraulic system, ie. in the pipes, between the master cylinder and the centering cylinder, there is a directional valve which is normally closed. The directional valve is affected by the flow monitor. When the directional valve is open, the two control chambers of the slave cylinder are connected and the support shaft is centered.
    In this described, and previously known, hydraulically controlled system, a steering in one direction for the steering shaft will cause the support shaft to be steered in the opposite direction, provided that the steering angle exceeds five degrees. If the steering angle is less than five degrees, the support shaft will be centered.
    According to a preferred embodiment, a centering of the support shaft is effected by actuating the directional valve, with the second control signal 24, so that it is opened. The invention also relates to a method in a control system for an articulated vehicle.
    The method will now be described with reference to the flow chart in Figure 5.
    The method is implemented in the control system for the vehicle which comprises a front vehicle part with a first longitudinal axis L1, and a rear vehicle part with a second longitudinal axis L2, where the vehicle parts are connected to each other via a joint which enables the vehicle parts to be pivotable relative to each other.
    The vehicle further comprises a steering wheel axle in the front vehicle part and a steerable support axle in the rear vehicle part. The method comprises the steps of: - determining the direction RV1 for an angle V1 of the wheels on the steering wheel axle relative to L1 in the forward direction of the vehicle, - determining the direction RVK for an angle VK at the joint between the first and second longitudinal axes (L1, L2), said first and second measuring units being adapted to output RV1 and RVK, respectively, to said processing unit, and that said processing unit is adapted to - determine a second control signal for control of the wheels on the steerable support shaft depending on at least RV1 and RVK so that if RV1 does not correspond to RVK, the second control signal is determined so that the steerable support shaft is centered, i.e. the wheels on the support shaft are aligned to roll substantially parallel to L2.
    According to an embodiment of the method, a gear position signal, containing information about the current gear vehicle in front of the vehicle, is taken into account when said second control signal is determined. This has been discussed above in connection with the description of the control system and reference is made to that description. This also applies to the description of the method when it is implemented for hydraulic steering of the steering wheel axle and the steerable support axle.
    Especially with regard to the control of a directional valve in connection with the hydraulically controlled support shaft which is adapted to be opened in dependence on said second control signal so that said support shaft is centered. The method is also applicable to the front and rear control units as these are electronically controlled hydraulic units.
    It has previously been described, in connection with the description of the control system, how the directions RV1 and RVK can be determined and reference is made here to that description regarding the application in connection with the method.
    When the directions for V1 and VK again correspond, and possibly other criteria, for example regarding gear selection and speed, are met, the function returns to normal, ie. the control of the support shaft takes place as usual.
    The present invention is not limited to the above-described preferred embodiments. Various alternatives, modifications and equivalents can be used.
    The above embodiments are therefore not to be construed as limiting the scope of the invention as defined by the appended claims.
    权利要求:
    Claims (16)
    [1]
    A control system (2) for an articulated vehicle (4), which vehicle comprises a front vehicle part (6) with a first longitudinal axis L1, and a rear vehicle part (8) with a second longitudinal axis L2, said vehicle parts being connected to each other via a joint (10) which enables the vehicle parts to be pivotable relative to each other, the vehicle further comprises a steering wheel axle (12) in the front vehicle part (6) and a steerable support shaft (14) in the rear vehicle part (8), wherein the control system comprises a processing unit (16), a front control unit (18) adapted to emit a first control signal (20) for controlling the wheels on the steering wheel axle (12), a rear control unit (22) adapted to emit a second control signal (24) for guiding the wheels on the steerable support axle (14), characterized in that the control system (2) further comprises a first measuring unit (26) adapted to determine the direction RV1 for an angle V1 of the wheels on the steering wheel axle (12) in relation to L 1 in the forward direction of the vehicle, a second measuring unit (28) adapted to determine the direction RVK for an angle VK at the joint (10) between the first and second longitudinal axes (L1, L2), said first and second measuring units (26, 28) being adapted to output RV1 and RVK, respectively, to said processing unit (16), and that said processing unit (16) is adapted to determine said second control signal (24) for said rear control unit (22) depending on at least RV1 and RVK so that if RV1 does not match with RVK, the second control signal (24) is determined so that the controllable support shaft (14) is centered.
    [2]
    The control system according to claim 1, wherein the processing unit (16) is adapted to receive a gear position signal (30), containing information on the current gear of the vehicle, and that said processing unit (16) is adapted to take into account this then said second control signal ( 24) determined.
    [3]
    The control system according to claim 1 or 2, wherein the processing unit (16) is adapted to receive a speed signal (32), containing information on the speed of the vehicle and that the processing unit (16) is adapted to compare the current speed with a current speed. number of threshold values for the speed and, depending on the result, the comparison take this into account when said second control signal (24) is determined.
    [4]
    The control system of any of claims 1-3, wherein said front (18) and rear (22) control units are hydraulic units.
    [5]
    The control system of claim 4, wherein said rear control unit comprises a directional valve, said directional valve being adapted to be opened depending on said second control signal so that said support shaft is centered.
    [6]
    The control system according to any one of claims 1-3, wherein said front (18) and rear (22) control units are electronically controlled hydraulic units.
    [7]
    The control system according to any one of claims 1-6, wherein the direction RV1 is determined so that RV1 = VR when the vehicle turns to the right and RV1 = VL when the vehicle turns to the left.
    [8]
    The control system according to any one of claims 1-7, wherein the direction RVK for the angle VK at the joint between the first and second longitudinal axes (L1, L2) on the right side of the vehicle, in the forward direction of the vehicle, is determined so that RVK = VR if VK is less than 180 degrees and RVK = VL if the angle is greater than 180 degrees.
    [9]
    A method in a control system for an articulated vehicle, which vehicle comprises a front vehicle part with a first longitudinal axis L1, and a rear vehicle part with a second longitudinal axis L2, said vehicle parts being connected to each other via a joint which enables the vehicle parts to be pivotable relative to each other, the vehicle further comprises a steering wheel axle in the front vehicle part and a steerable support axle in the rear vehicle part, characterized in that the method comprises the steps of: - determining the direction RV1 for an angle V1 of the wheels on the steering wheel axle in 10 15 20 25 30 13 in relation to L1 in the forward direction of the vehicle, - determine the direction RVK for an angle VK at the joint between the first and second longitudinal axes (L1, L2), said first and second measuring units being adapted to deliver RV1 and RVK to said processing unit, and that said processing unit is adapted to - determine a second control signal for controlling the wheels on the steerable the support shaft in dependence on at least RV1 and RVK so that if RV1 does not correspond to RVK, the second control signal is determined so that the controllable support shaft is centered.
    [10]
    The method of claim 9, wherein the method comprises taking into account a gear position signal, containing information about the current gear of the vehicle, when said second control signal is determined.
    [11]
    The method of claim 9 or 10, wherein the method comprises taking into account a speed signal, containing information on the current speed of the vehicle, when said second control signal is determined.
    [12]
    The method of any of claims 9-11, wherein the steerable wheel axle and the steerable support axle are hydraulically controlled.
    [13]
    The method according to claim 12, wherein a directional valve in connection with the hydraulically controlled support shaft is adapted to be opened in dependence on said second control signal so that said support shaft is centered.
    [14]
    The method of any of claims 9-11, wherein said front and rear control units are electronically controlled hydraulic units.
    [15]
    The method according to any one of claims 9-14, wherein the direction RV1 is determined so that RV1 = VR when the vehicle turns to the right and RV1 = VL when the vehicle turns to the left.
    [16]
    The method according to any one of claims 9-15, wherein the direction RVK for the 14th angle VK at the joint between the first and second longitudinal axes (L1, L2) on the right side of the vehicle, in the forward direction of the vehicle, is determined so that RVK = VR about VK is less than a maximum of 180 degrees and RVK = VL if the angle is greater than at least 180 degrees.
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    同族专利:
    公开号 | 公开日
    EP2716523B1|2019-06-19|
    SE538165C2|2016-03-22|
    EP2716523A2|2014-04-09|
    EP2716523A3|2018-01-03|
    BR102013024271A2|2017-07-11|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    US5289892A|1990-09-26|1994-03-01|Nissan Diesel Motor Co., Ltd.|Steerable trailer and steering apparatus of combination vehicle|
    US5244226A|1991-09-23|1993-09-14|Bergh C John|Trailer and steerable wheels therefor|
    DE10351482A1|2003-11-04|2005-06-09|Zf Lenksysteme Gmbh|Locking device for a hydraulic vehicle rear axle steering|
    WO2006005124A1|2004-07-13|2006-01-19|Gene Kostecki|Multiaxle vehicle with steerable rear wheels|
    US7793965B2|2006-02-10|2010-09-14|Padula Santo A|Trailer steering system for a tractor/trailer combination|
    DE102006059082B4|2006-12-14|2016-01-07|Robert Bosch Gmbh|Method for carrying out a steering operation in a vehicle with a trailer|
    US8469125B2|2011-03-25|2013-06-25|Honda Motor Co., Ltd.|System and method for controlling a trailer connected to a vehicle|DE102017126443A1|2017-11-10|2019-05-16|V.S.E. Vehicle Systems Engineering B.V.|Self-steering vehicle axle|
    法律状态:
    2021-06-01| NUG| Patent has lapsed|
    优先权:
    申请号 | 申请日 | 专利标题
    SE1251114A|SE538165C2|2012-10-03|2012-10-03|Control system for an articulated vehicle, and a method in an articulation system in an articulated vehicle|SE1251114A| SE538165C2|2012-10-03|2012-10-03|Control system for an articulated vehicle, and a method in an articulation system in an articulated vehicle|
    EP13184191.8A| EP2716523B1|2012-10-03|2013-09-12|Regulating system, and a method in a regulating system|
    BR102013024271-3A| BR102013024271A2|2012-10-03|2013-09-20|REGULATORY SYSTEM AND METHOD IN A REGULATORY SYSTEM|
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