method for designing and implementing hydraulic elements to achieve stable operating points under impact loads

产品开发的核心活动之一是不断地比较所需的产品功能和已实现的产品功能。其中许多验证活动都是在测试环境中进行的，以调查动态负载下的系统行为。动载荷的特例是周期性冲击载荷。这些高负载的作用时间很短，也将高能量转移到系统中。到目前为止，这些载荷还不能得到充分的验证，因为机械减振元件不能在周期性冲击载荷和高激励频率下实现稳定和可调的工作点。冲击载荷通常用来破坏材料。冲击应用系统的材料无损验证，例如锤子钻头或采矿锤子，正在增加，因为随着测试的重复性增加，可以节省时间和成本。这些系统的材料无损验证需要测试环境的高弹性，因为需要高阻尼性能和恒定的系统行为。自己的初步工作表明，静液压减振元件能够为冲击载荷提供稳定的工作点，磨损小，条件可调。然而，到目前为止，对于冲击载荷的液压减振元件的设计还没有支持，因为现有的支撑只涉及到具有较低减振性能的简谐激励的设计。本项目将为周期性冲击载荷的液压减振元件的设计提供系统的支持。在设计这种减震元件的同时研究的有条理的支撑，它允许识别在冲击载荷下的水力效应，如空化倾向。根据真实表面的冲击特性和机械元件的阻尼特性，确定了液压系统的要求，该机械元件能够吸收周期性冲击载荷，但具有非恒定的工作特性。然后对液压系统进行了仿真和设计。在开发方法中总结了设计活动。在设计的基础上，建立了液压解决方案作为研究对象。液压解决方案的物理验证能够识别冲击载荷下液压减振元件的影响，特别是关于目标可调整性或恒定系统行为的影响。这使得控制系统的设计能够在变化的冲击激励下实现恒定的阻尼特性。在开发方法中讨论了建立控制系统以实现可调和恒定阻尼行为的步骤，并展示了液压解决方案的附加值。

The continuous comparison between required and achieved product functions is one of the core activities in product development. Many of these validation activities take place in test environments to investigate the system behaviour under dynamic loads. Special cases of dynamic loads are cyclical impact loads. Those high loads act for a very short period of time and also a high energy is transferred to the system. These loads cannot be validated sufficiently up to now, as stable and adjustable operating points at cyclical impact loads and high excitation frequencies cannot be achieved with mechanical damping elements. Impact loads are often used to destroy materials. The material non-destructive validation of systems for impact applications, e.g. hammer drills or mining hammers, is increasing, since time and costs can be saved as the reproducibility of tests increases. The material non-destructive validation of these systems requires a high resilience of test environments, since a high damping performance together with a constant system behaviour is required. Own preliminary work has revealed that hydrostatic damping elements are capable of providing stable operating points for impact loads with low wear and adjustable conditions. Up to now, however, there is no support in the design of hydraulic damping elements for impact loads, as existing support only deals with designs regarding harmonic excitations with a lower damping performance. This project shall create a methodical support for the design of hydraulic damping elements for cyclical impact loads. The methodical support investigated in parallel to the design of such a damping element, which allows the identification of hydraulic effects, such as cavitation tendencies, under impact loads. Based on the impact behaviour of real surfaces and the damping behaviour of a mechanical element, which is able to absorb cyclical impact loads, but with non-constant operating behaviour, the requirements for a hydraulic system are determined. A hydraulic system is then simulated and designed. Design activities are summarized in the development method. Based on the design, the hydraulic solution is built as a research object. The physical validation of the hydraulic solution enables the identification of effects in hydraulic damping elements under impact loads, especially regarding the targeted adjustability or constant system behaviour. This enables the design of a control systems to achieve constant damping characteristics under changing impact excitations. Steps to build up a control system to achieve an adjustable and constant damping behaviour are dealt with in the development method and show the added value of hydraulic solutions.