Piezo-driven dispensers are precision dispensing devices for trace amounts of fluid and are widely used in the microelectronics packaging field. However, the preloading mechanism of piezo-driven dispensers easily loosens in high-frequency operation, and the design accuracy of the transmission ratio of the flexible displacement transmission mechanism (DTM) requires improvement. To address the aforementioned problems, we designed a self-locking preloading mechanism with an adjustable preloading amount for piezo-driven flexible transmission dispensers and investigated the method of designing the transmission ratio considering the non-expected directional deformation (parasitic deformation). First, the principle of the preloading mechanism was analyzed, and a method for adjusting the droplet diameter based on the preloading amount was proposed. Second, an asymmetric flexible-hinge compliance matrix calculation method was proposed, a transmission ratio model of the DTM was established, and the influence law of the structural parameters on the transmission ratio was comparatively analyzed using ANSYS software. Based on the output displacement requirement, transmission ratios were designed and structural parameters were determined. Finally, based on the piezoelectric coupling simulation, a piezo-driven dispenser was manufactured, and a test platform was built to conduct the relevant tests. The simulation and test results demonstrated that the maximum relative errors of the transmission-ratio calculated by the proposed transmission-ratio model were 1.54% and 3.6%, respectively, compared to the simulation and test results, confirming that the model was correct. Single-factor tests confirmed that a preloading mechanism can fix and preload the piezostack and that the droplet diameters can be adjusted with the preloading amounts. The operating frequency was up to 800 Hz with a diameter of 0.30 mm and a consistency of 4.32%, which meet the requirements of dispensing efficiency in the microelectronics packaging field. This study has practical significance for enhancing the transmission ratio design accuracy and dispensing performance of dispensers.

中文翻译：

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柔性铰接压电驱动分配器的设计与性能分析

压电驱动点胶机是微量流体的精密点胶设备，广泛应用于微电子封装领域。然而，压电驱动点胶机的预紧机构在高频操作中容易松动，柔性位移传动机构（DTM）的传动比设计精度有待提高。针对上述问题，我们设计了一种用于压电驱动柔性传动分配器的预紧量可调的自锁预紧机构，并研究了考虑非预期方向变形（寄生变形）的传动比设计方法。首先分析了预加载机理，提出了一种基于预加载量调节液滴直径的方法。其次，提出了非对称柔性铰链柔度矩阵计算方法，建立了DTM的传动比模型，并利用ANSYS软件对比分析了结构参数对传动比的影响规律。根据输出排量要求，设计传动比并确定结构参数。最后，基于压电耦合仿真，制作了压电驱动点胶机，并搭建了测试平台进行相关测试。仿真和测试结果表明，与仿真和测试结果相比，所提出的传输比模型计算出的传输比的最大相对误差分别为1.54%和3.6%，证实了模型的正确性。单因素测试证实，预加载机构可以固定并预加载压电堆栈，并且可以通过预加载量来调整液滴直径。工作频率高达800Hz，直径0.30mm，一致性4.32%，满足微电子封装领域点胶效率要求。本研究对于提高点胶机的传动比设计精度和点胶性能具有实际意义。