Friction-reduced hydrodynamic sliding linear bearing with diminished inclination of tilting to increase the sliding velocity by means of optimal design of the sliding surfaces

减摩流体动压滑动直线轴承，通过滑动表面的优化设计，减小倾斜度，提高滑动速度

• 批准号: 285064832
• 负责人: Professor Dr.-Ing. Martin Dix, since 4/2021
• 金额: --
• 依托单位: Professur für Werkzeugmaschinenkonstruktion und Umformtechnik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2016
• 资助国家: 德国
• 起止时间: 2015-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/285064832?language=en
• 关键词: Friction; reduced; hydrodynamic; sliding; linear

The high load capacities combined with excellent damping properties are the reasons why hydrodynamic guides (HDG) are still used in machine tools. A very high surface quality of the workpieces is achieved by damping the process forces. The HDG systems should preferably be operated in the area of fluid friction. The aim of the continuation proposal is to improve the accuracy of hydrodynamic guides during operation, i.e. constant floating behaviour independent of time and position through purposeful control of the start-up mechanisms. For this purpose, the first aspect to be shortened is the mixed friction area in the Stribeck diagram of the guide, i.e. the liquid friction area is reached at the lowest possible speed. The second aspect of the accuracy behaviour is the desired constance of the lubricating gap with fluid friction, i.e. the avoidance or minimisation of tilting of the carriage.The third criterion is the minimal increase in floating height with increasing speed, which must be determinable by the purposeful control of various mechanisms. The objective follows on from the current DFG project, in which the floating behaviour at constant speed was described only with a defined or experimentally determined initial position of the carriage. In contrast, the velocity profile of machine tools typical reversing movements always consists of 3 phases: Acceleration, constant speed and deceleration, which are in permanent repetition. Starting from the stillstand position - i.e. without a significant lubricating gap - is rather an exception, since there is not enough time between the single strokes for the oil to be pressed out of the lubricating gap. The following challenges arise from the objective, the solution of which in its entirety enables an effective design and optimal operation of the hydrodynamic guidance system:- Improvement of the measurement of hydrodynamic pressure in the lubrication gap and displacement pressure at the inlet edge- Modelling and control of the start-up process- Modulation of lubrication parameters- Adjustment of the concavity of the contact surfaceThe approach is to control and shape the start-up process in a specific way. For this purpose, the characteristics of the lubricating wedge must be mastered when starting from the initial position or after a reversal of direction. The interdependence of the three adjustable influences is particularly complex: the defined acceleration profile within the movement cycle, the lubrication and the geometry of the contact surface. The work programme dedicates one AP to each of these aspects. It is completed by work to improve the mathematical-technical understanding of the start-up and, in particular, to improve the pressure measurement system.

高负载能力和优异的阻尼性能是流体动力导轨（HDG）仍然在机床中使用的原因。工件的高表面质量是通过降低加工力来实现的。HDG系统最好在流体摩擦区域运行。延续方案的目的是通过有目的地控制启动机构，提高流体动力导轨在运行过程中的精度，即不受时间和位置影响的恒定浮动行为。为此，首先要缩短的是导轨Stribeck图中的混合摩擦区，即以尽可能低的速度到达液体摩擦区。精度行为的第二个方面是润滑间隙与流体摩擦的期望常数，即避免或最小化车厢的倾斜。第三个标准是随着速度的增加浮动高度的最小增量，这必须通过各种机构的有目的控制来确定。该目标遵循当前的DFG项目，其中恒定速度下的浮动行为仅通过定义或实验确定的载体初始位置来描述。相比之下，机床典型换向运动的速度曲线通常由加速、匀速和减速三个阶段组成，这三个阶段是永久重复的。从静止位置开始-即没有明显的润滑间隙-是一个例外，因为在单冲程之间没有足够的时间将油压出润滑间隙。以下挑战来自于这一目标：其整体解决方案使流体动力导向系统的有效设计和最佳运行成为可能：-改进润滑间隙流体动力压力和进口边缘位移压力的测量-启动过程的建模和控制-润滑参数的调制-接触面凹凸度的调整-方法是以特定的方式控制和塑造启动过程。为此，在从初始位置开始或方向反转后，必须掌握润滑楔的特性。这三种可调节影响的相互关系特别复杂：运动周期内定义的加速度剖面、润滑和接触面的几何形状。该工作方案为每一个方面专门制定了一个AP。它是通过提高对启动的数学技术理解，特别是改进压力测量系统来完成的。