CN100443317C - 带有摆动角传感器的球形万向节 - Google Patents
带有摆动角传感器的球形万向节 Download PDFInfo
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- F16C11/0619—Ball-joints; Other joints having more than one degree of angular freedom, i.e. universal joints the female part comprising a blind socket receiving the male part
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Abstract
本发明涉及一种带有用于测量万向节壳体(4)与球轴颈(3)之间相对角位的摆动角传感器(9)的球形万向节(1)。其中万向节球(2)的摆动角α由包括磁体(8)和磁场传感器(9)在内的测量装置测得。根据本发明,对于一个系列中的每种球形万向节,选择磁体(8)的位置和大小以及万向节球(2)凹部的位置和大小,以便在达到球形万向节(1)的公称摆动角αm时,使穿过磁场传感器(9)的磁力线(12)的角度K大致与适用于整个系列的常数Km相一致。由此,在整个球形万向节系列中,可以跨类型地基本采用同一个磁场传感器(9)并将其跨类型地设置在同一传感器壳体(7)内及球形万向节(1)的同一位置上。因为由此而减少了部件的种类并简化了球形万向节系列的设计,所以能显著地节约成本。
Description
本发明涉及一种如权利要求1前序部分所述的带有摆动角传感器的球形万向节。
前述类型的球形万向节,例如但不局限于使用在汽车的底盘上。例如,这种带有摆动角传感器的球形万向节可以用于确定各种底盘部件相互间的相对位置或诸如车轴和车身之间的相对位置,或为了在车辆电子***中再处理而进行测量。对于现代汽车而言,这对例如行驶动态调整、自动水平调整或者头灯***的动态照射范围调节都很有意义。
对于这种***,对于进行具有很高重复精度的、可靠和准确的球形万向节角位检测,以及摆动角传感器的快速动态响应都很重要。另外,由于此类球形万向节在底盘区域中的结构,承受例如通过振动而产生的极大的机械负荷和由诸如潮湿、沙或散布的盐的周围介质而造成的严重影响。此外,使用者方面还要求在成本较低的同时,有长的使用寿命、故障安全性和无需维修性。
为了满足这些要求,经证明有效的是在此类球形万向节中集成非接触工作的,尤其是基于磁场作用的、用于摆动角检测的***。其中,大多数是在球形万向节上设置永磁体而在万向节壳体中设置磁场传感器,特别是磁阻类(MR)的磁场传感器。MR-传感器的输出信号随着穿过其中的磁力线的方向变化而变,这决定了它可以用于具有检测摆动角功能的球形万向节。
例如,此类球形万向节被DE10110738A1所公开。这种球形万向节具有设置在万向节球中的条状磁铁和固定在万向节壳体上的磁场传感器。
由于实践中对于每种车辆类型不同的结构,这类带摆动角检测装置的球形万向节结构不同,或底盘几何形状不同,或者由于照射范围调节或行驶动态调整之类的电子控制***的设计不同,在大多数情况下必须针对车辆或应用对此类球形万向节进行特别构思和设计。这就有理由为了达到尽可能高的角度检测精度而应当充分利用磁场传感器的整个测量范围。但应该要保证对磁场传感器的整个测量范围的充分利用与在球形万向节上出现的最大摆动角或公称摆动角的大小无关。
换句话说,这意味着根据现有技术,实践中针对每种应用要特别确定万向节球、永磁体和尤其是磁场传感器组合的尺寸,以使转过球形万向节的公称摆动角时,穿过磁场传感器的磁场的变化能达到随着公称摆动角的转过而充分利用尽可能大的磁场传感器测量范围部分的程度。
但这种针对应用的、此类球形万向节中所有角度检测所需的部件的设计是费事的且昂贵的。这特别适于每种磁场传感器在球形万向节壳体上的定位、大小、灵敏度和空间设置的对应所需适配。
在此背景下,本发明的任务是给出一种带有摆动角检测装置的球形万向节,该球形万向节能克服上述缺点,并且能决定性地降低摆动角检测***适配的支出。通过这种方式,可以实现快速开发,并由此减少了开发、制造以及采购和存储的费用。
这个任务通过具有权利要求1所述特征的球形万向节实现。
从属权利要求的内容为优选的实施方式。
公知地,本发明的球形万向节首先显然具有用于获得万向节壳体与球轴颈或万向节球之间的相对角位置的摆动角传感器。其中,为了检测摆动角,首先采用了一种由嵌入万向节球中的磁体和设于万向节壳体上的磁场传感器而构成的已知组合。
本发明的球形万向节的特征在于,在一个球形万向节系列中对于每种球形万向节类型针对应用情况、磁体在万向节球中的位置和大小以及容纳磁体的凹部在万向节球中的位置和大小的选择都要能实现,当达到对应球形万向节的公称摆动角αm时,穿过磁场传感器的磁力线的角度κ几乎与适用于整个系列的常数值κm一致。
换句话说,这意味着本发明仅通过万向节球或具有万向节球的球轴颈的相应设计,以及同样通过设于万向节球上的磁体的相应构成和设计来影响磁体和环绕万向节球的磁场的形状、强度和扩展,从而在转过球形万向节的公称摆动角时,能与类型无关地充分利用磁场传感器的整个可使用的测量范围。
极其有益的是,因为现在可跨类型地,例如在一个球形万向节系列中,基本上只采用同一种磁场传感器,由此也能跨类型地在同一个传感器壳体中以及球形万向节的同一个位置上设置磁场传感器。很明显,由此可以在开发、采购、存储、制造和物流中节省可观的支出,并且能显著缩短响应变化了的客户需求的响应时间。
尤其优选的是,其中常数κm基本上与磁场传感器所能测得的最大磁场角度对应。通过这种方式,可以在磁场传感器上量取与球形万向节的摆动角对应的、具有尽可能大的分辨率和重复精度的测量信号。
对于本发明来说,采用何种磁性作用原理以及万向节球与磁体组合的形式和结构如何并不很重要,只要磁场传感器由此在球形万向节绕其公称角回转的过程中能产生所需的磁场变化就行。
根据本发明的一个优选实施方式,采用了简单的条形磁体作为磁体,其磁轴线最好与球轴颈的轴线一致。这种设计结构上特别简单并且成本低,而且角度量取可靠,测量不受球形万向节工作中可能出现的球轴颈围绕其自身轴线的转动的影响。特别好的是,磁体设置在与球轴颈相对的万向节球的极区域。
根据本发明的另一个优选实施方式,磁场传感器设置在远离球轴颈的万向节壳体的开口区域或者位于该位置上的闭合盖区域内。特别有利的是磁场传感器的磁性对称轴线与万向节壳体的对称轴线,或者与球轴颈的轴线在其中间位置处重合。
以球形万向节简单构造的方式,以及为了可靠测得摆动角,上面所说的优选的磁体布置方式好处在于其与球轴颈在万向节壳体中可能出现的转动无关。其中磁场传感器最好设置在合成材料元件中或者嵌入合成材料元件内。合成材料元件最好同时具有作为位于万向节壳体的与球轴颈相对侧上的万向节壳体闭合盖的功能,这有助于简化设计以及节省与之对应的费用,并且提高球形万向节的可靠性。
对于本发明的本质来说,采用何种方式来连接磁体与万向节球,或者将磁体嵌入万向节球内并不重要。磁体的造型对于本发明也不重要,只要磁力线在磁场传感器区域内能实现所期望的分布就行。最好通过一个弹性辅助体实现磁体在万向节球中的嵌入,根据本发明特别优选的实施形式,该辅助体由弹性材料或合成材料制成。
根据本发明的优选实施方式,磁体同样具有基本上条形、圆柱状形状,将磁体嵌入万向节球的凹部中的辅助体基本上为圆柱环形状。
换句话说,为了连接磁体与万向节球,万向节球仅包括一个基本上呈圆柱形的凹部,在该凹部内放入或压入最好合成材料制成的、环形辅助体,随后在辅助体的凹部中再放入、压入或粘入磁体。
此外,根据本发明的另一个实施方式,弹性的辅助体还可构造成基本上呈环形、最好由非铁磁性材料组成的弹簧;其中根据另一个实施方式,环形弹簧还至少局部用合成材料注塑包封以容纳磁体。通过这种方式,一方面能特别容易地装配磁体,另一方面通过环形弹簧,尤其是通过合成材料注塑包封的弹簧来实现磁体在万向节球中的耐振固定。
通过基本上呈圆柱环形或环形的辅助体或者通过基本上呈环形的弹簧实现磁体在万向节球中的嵌入,其突出的好处在于:当通过这种方式使磁体在万向节球中的位置和大小以及凹部在万向节球中的位置和大小主要依赖于磁场的形式、强度和范围时,能够特别简单和相互独立地进行优化,从而正好形成摆动角传感器最大分辨率所必需的特殊磁场。
下面,依据仅显示实施例的附图进一步说明本发明。
图示为:
图1用于测摆动角的球形万向节的一个实施例的局部剖侧视图;
图2穿过图1所示球形万向节的万向节球和磁体的纵剖面的示意图;
图3图2所示纵剖面的示意图以及磁力线的分布;
图4根据图2的磁力线角κ随着万向节球的摆动角α而变化的曲线图;
图5与图3相应的另外一个球形万向节的万向节球的纵剖面和磁力线分布图;
图6与图4相应的、根据图5的磁力线角κ随着万向节球的摆动角α而变化的曲线图;
图7经过球形万向节的另一实施方式的万向节球和磁体的纵剖面的示意图;
图8与图7对应的、图7所示的万向节球仰视图;
图9与图7和8对应的、经过球形万向节的另一实施方式的万向节球和磁体的纵剖面图;
图10与图7到9对应的图9所示的万向节球的仰视图。
图1中显示了球形万向节1的局部纵剖面。球形万向节1基本上由包含万向节球2的球轴颈3和万向节壳体4及置于其中的轴瓦5组成。球形万向节1还进一步包括合成橡胶波纹管6和壳体盖7,其用于保护万向节球2和轴瓦5免受尘埃和潮湿侵入的影响。
此外,球形万向节1还设有用于确定球轴颈3相对于万向节壳体4的摆动角位置的装置。一方面,该角测量装置包括永磁体8,该永磁体8设置在万向节球2远离轴颈的极区域内的万向节球2的凹部内。另一方面,角测量装置包括磁场传感器9,该磁场传感器9设置在朝向万向节壳体4的壳体盖7内侧。
在所示的实施例中,磁场传感器9为所谓的磁阻传感器(MR-传感器),其特点在于,其输出信号显示了穿过传感器的磁力线的角度的直接值。
从图1中可以同样进一步看出,在万向节球2的极区域内的凹部中设置有用于将永磁体8嵌入万向节球2中的合成材料环10。另外还可看出,通过选择具有确定大小和强度的磁体8和与之对应的构造,可能还有对合成材料环10的材料选择,可以使磁体8的磁场的特性曲线在较宽的范围内变化,而不必对球形万向节的任何类型另做改变。
除了磁体8本身及对于磁场起决定作用的特性,例如磁体8的大小和强度之外,合成材料环10除了起将磁体8固定在万向节球2中的作用之外,还可以作为主动影响磁场的部件。例如,这可以通过选择非磁惰性的,特别是影响磁力线走向的合成材料环10材料来实现。此外,磁体8也能由合成材料材料制造,其中为了制造磁体8而采用可磁化的合成材料材料。通过这种方式,磁体8和合成材料环10甚至可以做成一体,例如通过熔接可复合挤压制造的部件来实现。
在图2中,为清楚起见仅再次显示了图1所示的球形万向节1的万向节球2。可从图中看出在万向节球2的下极区域内,设置在那里的圆柱形凹部中的合成材料环10和嵌入在合成材料环10中心的永磁体8及磁场传感器9。当万向节球2相对于未图示的万向节壳体4回转时,其中磁场传感器9通过图2中同样未显示的壳体盖与该万向节壳体4连接,磁场传感器9相对于万向节球2沿着弯曲部分11移动,其中穿过磁场传感器9的磁体8的磁力线方向与万向节球2的摆动角相关,从而使磁传感器9的输出信号相应变化。
在图3中,图2的万向节球2和磁场传感器9仅被示意性地重新显示出来。此外,图3还显示了设置于万向节球2中的磁体8的磁力线12的分布。用α标记的角示例性表示万向节球2相对于万向节壳体4的摆动的大小,而κ表示穿过磁场传感器9的磁力线的角度。与图3所示相关,例如当万向节球2摆动角α1时,磁体8的磁力线以角κ1穿过相对于万向节球2、位于附图标记13位置处的磁场传感器9,从而产生与角κ1对应的磁场传感器9的输出信号。
在图4中,角κ或与之对应的磁场传感器9的输出信号依赖于万向节球2的摆动角α。可以看出,由磁场传感器9提供的角信号和对应的万向节球2的摆动角之间实际上呈线性的关系,这对于精确地和以尽可能大的分辨率确定万向节球2相对于万向节壳体4的摆动角十分必要。
在图5中示意性地显示了另外一种球形万向节1的万向节球2以及对应的磁力线12分布。与图3所示的万向节球2相比,图5所示的万向节球2具有直径更小的磁体凹部。根据图5,万向节球2磁体凹部的较小直径通过采用具有更小外径的合成材料环10实现,其中如图5所示的磁体8具有与图3所示的磁体8相同的大小。对比图3和5就能看出,只被改变的磁体8尺寸和万向节球2的包含合成材料环10的凹部导致了磁场构成和磁力线12分布的改变。从而,磁场传感器9反应的相应变化与万向节球2在万向节壳体4中的回转运动相联系。
结合图5和图3就能很清楚地看出这点。在图3以及图5中,在附图标记13处穿过磁场传感器9的磁力线12的角用κ1表示。其中,角κ1和由此磁场传感器9的输出信号在图3及图5中大小相等。与图3相比,由于图5中的磁场形状不同,图5的磁场具有互相之间特别靠近的磁力线,在磁力线正好以角κ1穿过磁场传感器9的位置13或万向节球2与万向节壳体4相对角位置,在图5所示的球中比图3所示的球中在万向节球2的中性位置或中间位置明显地更靠近。
换句话说,如图5所示,万向节球2进行大小为α2的较小偏转时出现磁力线角κ1或磁场传感器9的相应输出信号;而如图3所示,相同大小的磁力线角κ1或磁场传感器9的相等输出信号在万向节球2进行大小为α1的较大偏转时才出现。
通过对比图4和图6,这种相互关系看得更为清楚。其中图4所示的曲线对应于图3所示的结构,而图6的曲线对应于图5所示的结构。通过比较图4和图6可以看出,对于图3所示的结构当万向节球2的摆动角大致为α1=15°时才达到的输出信号κ1,而对于图3的结构,当万向节球2的摆动角大致为α2=12°时已达到相同的输出信号κ1。此外,对于所示的实施方式,对应于大约90°的磁力线角的最大输出信号κm,对于图3所示结构当万向节球2回转大约αm=27°时才达到,而图5所示的结构中万向节球偏转大约αm=21°时就达到相同的最大输出信号κm。换句话说,具有本发明的万向节球2及磁体8的结构,及还可能有的合成材料环10的结构设置的球形万向节1,可以跨类型地在一系列球形万向节中用同一个磁场传感器9和同一个传感器壳体7就够了,其中对于球形万向节系列的每种球形万向节类型,磁场传感器9都可以设置于相同的位置上。根据本发明,只需通过适配磁体8在万向节球2中的位置和大小以及凹部在万向节球2中的位置和大小及必要时合成材料环7的位和大小,就能保证球形万向节系列中的每个球形万向节1在回转过球形万向节1的公称摆动角时,充分利用在整个系列中所采用的不变的磁场传感器9的整个可用的信号范围。
在图7到10中显示了另外两个球形万向节1的实施方式的万向节球。图7中,可以看出除纵剖的万向节球2和磁体8还有环形的辅助体14,在万向节1的这个实施方式中辅助体14被制成基本上呈环形的弹簧14,其中最好用非铁磁性材料制造为了将磁体8***圆柱形的万向节球2的凹部的环形弹簧14,以免影响或减弱磁场。
图8显示了图7所示万向节球2的仰视图。可以看出除中心设置的磁体8外还有特别例如通过冲压制造的、环形弹簧14的结构,该弹簧通过多个舌形弹簧突起部15支承在万向节球2的圆柱形凹部的外缘上。
图9显示了球形万向节1另一个实施方式的万向节球2的纵剖面。所示的万向节球2同样具有基本上呈环形的弹簧14,以用于将磁体8***万向节球2的圆柱形凹部中。其中,接纳磁体8的环形弹簧14的中心区域还另外用合成材料材料16注塑包封。这是为了更好地将磁体8***万向节球2的圆柱形凹部中,尤其是更好地抵御在球形万向节1工作中出现的振动。
最后,图10再次显示了图9所示的万向节球的仰视图。除了环形弹簧14与图8相同具有用于将弹簧14支承于万向节球2的圆柱形凹部中的多个弹簧突起部15,可看到该环形弹簧14的用合成材料材料注塑包封的中心区域,由于该区域而使磁体8在该视图中被遮住。
结果很明显,因为根据本发明针对客户的球形万向节的转换设计可以仅局限在万向节球和磁体设置上,所以本发明很明显地减少了确定用于摆动角检测的球形万向节的尺寸的设计费用,尤其是减少了针对客户的、计算和设计此类球形万向节的费用。磁场传感器的形式、实施、设置和位置一直不变。由此,一方面明显地节省了支出,另一方面决定性地减少了针对客户愿望和要求的反应时间。
附图标记列表
1球形万向节
2万向节球
3球轴颈
4万向节壳体
5轴瓦
6合成橡胶波纹管
7壳体盖
8永磁体
9磁场传感器
10合成材料环
11弯曲部分
12磁力线
13传感器坐标点
14辅助体(弹簧)
15弹簧凸起部
16合成材料
α角
κ角
Claims (13)
1.一种球形万向节,其带有用于检测万向节壳体(4)与球轴颈(3)之间相对角位的摆动角传感器(9),还带有嵌入万向节球(2)的一个凹部内的一个磁体(8)和设置于万向节壳体(4)处的一个磁场传感器(9),其特征在于,
对于一个将万向节球的适配局限到万向节球和磁体布置的球形万向节系列,选择磁体(8)在万向节球(2)中的位置和大小以及凹部在万向节球(2)中的位置和大小,使当达到对应的球形万向节(1)的公称摆动角αm时,穿过磁场传感器(9)的磁力线(12)的角κ与适用于整个系列的常数κm基本一致。
2.如权利要求1所述的球形万向节,其特征在于,
常数κm基本上与磁场传感器(9)能检测到的最大磁场角一致。
3.如权利要求1或2所述的球形万向节,其特征在于,
所述磁体(8)为条状磁体,其磁轴线与球轴颈(3)的轴线一致。
4.如权利要求1到3之一所述的球形万向节,其特征在于,
所述磁体(8)设置于万向节球(2)远离球轴颈的极区域。
5.如权利要求1到4之一所述的球形万向节,其特征在于,
所述传感器(9)设置于万向节壳体(4)的闭合盖(7)区域内。
6.如权利要求1到5之一所述的球形万向节,其特征在于,
所述传感器(9)的磁对称轴线与万向节壳体(4)或球轴颈(3)的对称轴线重合。
7.如权利要求1到6之一所述的球形万向节,其特征在于,
所述传感器(9)设置或嵌入在合成材料元件(7)内。
8.如权利要求7所述的球形万向节,其特征在于,
所述合成材料元件(7)起到万向节壳体(4)的闭合盖(7)的作用。
9.如权利要求1到8之一所述的球形万向节,其特征在于,
所述磁体(8)通过弹性辅助体(10)被嵌入和固定入万向节球(2)中。
10.如权利要求9所述的球形万向节,其特征在于,
所述弹性辅助体(10)由聚合物制成。
11.如权利要求9或10所述的球形万向节,其特征在于,
所述磁体(8)基本上呈圆柱形,所述弹性辅助体(10)具有基本上为圆柱环形的结构。
12.如权利要求9到11之一所述的球形万向节,其特征在于,
所述弹性辅助体(10)用非铁磁性的材料制成且基本上为环形的弹簧(14)。
13.如权利要求12所述的球形万向节,其特征在于,
所述环形弹簧(14)至少局部地用合成材料(16)注塑包封。
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- 2004-08-11 JP JP2006523516A patent/JP4560044B2/ja not_active Expired - Fee Related
- 2004-08-11 EP EP04762645A patent/EP1656268B1/de active Active
- 2004-08-11 WO PCT/DE2004/001800 patent/WO2005021296A1/de active IP Right Grant
- 2004-08-11 KR KR1020057025311A patent/KR100900365B1/ko not_active IP Right Cessation
- 2004-08-11 CN CNB2004800107126A patent/CN100443317C/zh not_active Expired - Fee Related
- 2004-08-11 DE DE502004005376T patent/DE502004005376D1/de active Active
- 2004-08-11 AT AT04762645T patent/ATE376938T1/de not_active IP Right Cessation
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Also Published As
Publication number | Publication date |
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KR20060039875A (ko) | 2006-05-09 |
DE502004005376D1 (de) | 2007-12-13 |
DE10338833A1 (de) | 2005-03-17 |
ATE376938T1 (de) | 2007-11-15 |
EP1656268A1 (de) | 2006-05-17 |
MXPA05012416A (es) | 2006-05-17 |
JP2007502944A (ja) | 2007-02-15 |
EP1656268B1 (de) | 2007-10-31 |
JP4560044B2 (ja) | 2010-10-13 |
KR100900365B1 (ko) | 2009-06-02 |
DE10338833B4 (de) | 2005-12-22 |
US7170285B2 (en) | 2007-01-30 |
WO2005021296A1 (de) | 2005-03-10 |
US20060078369A1 (en) | 2006-04-13 |
CN1777519A (zh) | 2006-05-24 |
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