ON THE NEW MECHANICAL PRESS WITH A PLANETARY GEAR TRAIN

2016 ◽  
Vol 40 (1) ◽  
pp. 45-58 ◽  
Author(s):  
Ren-Chung Soong
Keyword(s):  
Dynamic Performance ◽  
Planetary Gear ◽  
Cost Effective ◽  
Gear Train ◽  
Dimensional Synthesis ◽  
Linkage Mechanism ◽  
Planetary Gear Train ◽  
The Press ◽  
Mechanical Press ◽  
Crank Mechanism

A new 1-DOF mechanical press with a geared eight-bar linkage mechanism is presented. The proposed press can generate the required kinematic and dynamic performance for drawing, stamping, deep drawing, and precision cutting processes by simply adjusting the offset of the ram. The press consists of an elementary planetary gear train with a pair of planet gears, a slider-crank mechanism, and a slider-crank mechanism with a variable-length crank. The configuration and a solid model are described, and a kinematic analysis, dynamic analysis, and optimized dimensional synthesis of the press are discussed. Examples are provided to verify the feasibility and effectiveness of the design methodology. The proposed press could lead to more flexible and cost-effective applications.

scholarly journals Design of Vegetable Pot Seedling Pick-up Mechanism with Planetary Gear Train

2020 ◽  
Vol 33 (1) ◽  
Author(s):  
Zhipeng Tong ◽  
Gaohong Yu ◽  
Xiong Zhao ◽  
Pengfei Liu ◽  
Bingliang Ye
Keyword(s):  
Design Method ◽  
Planetary Gear ◽  
Gear Train ◽  
Dimensional Synthesis ◽  
Planetary Gear Train ◽  
Key Points ◽  
Physical Prototype ◽  
Noncircular Gears ◽  
Pitch Curve ◽  
Parameter Values

Abstract It has been challenging to design seedling pick-up mechanism based on given key points and trajectories, because it involves dimensional synthesis and rod length optimization. In this paper, the dimensional synthesis of seedling pick-up mechanism with planetary gear train was studied based on the data of given key points and the trajectory of the endpoint of seedling pick-up mechanism. Given the positions and orientations requirements of the five key points, the study first conducted a dimensional synthesis of the linkage size and center of rotation. The next steps were to select a reasonable solution and optimize the data values based on the ideal seedling trajectory. The link motion was driven by the planetary gear train of the two-stage gear. Four pitch curves of noncircular gears were obtained by calculating and distributing the transmission ratio according to the data. For the pitch curve with two convex points, the tooth profile design method of incomplete noncircular gear was applied. The seedling pick-up mechanism was tested by a virtual prototype and a physical prototype designed with the obtained parameter values. The results were consistent with the theoretical design requirements, confirming that the mechanism meets the expected requirements for picking seedlings up. This paper presents a new design method of vegetable pot seedling pick-up mechanism for an automatic vegetable transplanter.

Study on a Kind of Active Balancer Using Planetary Gear Train

2014 ◽  
Vol 701-702 ◽  
pp. 761-768
Author(s):  
Ying Zhang ◽  
Chong Peng ◽  
Yu Dong Wang
Keyword(s):  
Working Conditions ◽  
Structural Parameters ◽  
Dynamic Performance ◽  
Design Procedure ◽  
Planetary Gear ◽  
Gear Train ◽  
Original Structure ◽  
Dynamic Balancing ◽  
Planetary Gear Train ◽  
Structure And Motion

A kind of active balancer using planetary gear train was developed as a solution for dynamic balancing, aiming to balance the mechanisms actively and bring little changes to their original structure and motion. It consists of a two-DOF planetary gear train and a controllable motor. One of the two inputs doubles as the output, connected to the machine to be balanced. The other input is driven by the control motor. The conceptual design of the proposed balancer was discussed. Taking one scheme as example, design procedure of the balancer was introduced. Numerical examples were given to demonstrate the effectiveness of the proposed balancer. The results showed that much more flexibility on the dynamic performance under different working conditions were achieved by selecting suitable input speed trajectories and structural parameters of the planetary gear train of the active balancer.

Novel approach for planetary gear train dimensional synthesis through kinematic mapping

2019 ◽  
Vol 234 (1) ◽  
pp. 273-288 ◽  
Author(s):  
Liang Sun ◽  
Zhenfei Wang ◽  
Chuanyu Wu ◽  
Guofeng Zhang
Keyword(s):  
Angular Displacement ◽  
Planetary Gear ◽  
Gear Ratio ◽  
Gear Train ◽  
Transmission Ratio ◽  
Dimensional Synthesis ◽  
Open Chain ◽  
Planetary Gear Train ◽  
Kinematic Mapping ◽  
Noncircular Gears

The synthesis of a kinematic trajectory traversed by an output link (planet gear) and posture of a planetary gear train with noncircular gears can be divided into two phases: dimensional synthesis of the open-chain 2R mechanism (planetary carrier) and optimization of the transmission ratio of noncircular gear pairs. According to kinematic mapping theory, more than one closed coupler trajectory can be obtained by five preset poses. Simultaneous consideration of the trajectory shape, posture, and gear ratio is difficult during planetary gear train synthesis. This work therefore proposes a new method for the synthesis of planetary gear train in which different path segments in different trajectories are selected and a group of same-type 2R mechanisms is employed to pass through them in order to rebuild a new, closed trajectory. Subsequently, the transmission ratio of noncircular gear pairs can be determined using the relative angular displacement of the 2R mechanism. To improve the roundness of the pitch curves of noncircular gears, two optimization steps are implemented using a genetic algorithm without alternating the data points of the requisite open trajectories. For example, a mechanism for rice pot seedling transplanting is obtained by using the method.

Dynamic Characteristics of Double Helical Planetary Gear Train With Tooth Friction

2015 ◽  
Author(s):  
Fengxia Lu ◽  
Rupeng Zhu ◽  
Haofei Wang ◽  
Heyun Bao ◽  
Miaomiao Li
Keyword(s):  
Degrees Of Freedom ◽  
Sliding Friction ◽  
Planetary Gear ◽  
Gear Train ◽  
Variable Step Size ◽  
Step Size ◽  
Planetary Gear Train ◽  
Gear Mesh ◽  
Meshing Stiffness ◽  
Nonlinear Dynamics Model

A new nonlinear dynamics model of the double helical planetary gear train with 44 degrees of freedom is developed, and the coupling effects of the sliding friction, time-varying meshing stiffness, gear backlashes, axial stagger as well as gear mesh errors, are taken into consideration. The solution of the differential governing equation of motion is solved by variable step-size Runge-Kutta numerical integration method. The influence of tooth friction on the periodic vibration and nonlinear vibration are investigated. The results show that tooth friction makes the system motion become stable by the effects of the periodic attractor under the specific meshing frequency and leads to the frequency delay for the bifurcation behavior and jump phenomenon in the system.

Specific Conditions of A I ¯ -Planetary Gear Train

2019 ◽  
pp. 27-30
Author(s):  
Kiril Arnaudov ◽  
Dimitar Petkov Karaivanov
Keyword(s):  
Planetary Gear ◽  
Gear Train ◽  
Planetary Gear Train

Examples for Application of A I ¯ -Planetary Gear Train

2019 ◽  
pp. 187-204
Author(s):  
Kiril Arnaudov ◽  
Dimitar Petkov Karaivanov
Keyword(s):  
Planetary Gear ◽  
Gear Train ◽  
Planetary Gear Train

Optimization of A I ¯ -Planetary Gear Train

2019 ◽  
pp. 173-180
Author(s):  
Kiril Arnaudov ◽  
Dimitar Petkov Karaivanov
Keyword(s):  
Planetary Gear ◽  
Gear Train ◽  
Planetary Gear Train

Design, Synthesis and Experiment of Foot-driven Lower Limb Rehabilitation Mechanisms

2021 ◽  
pp. 1-44
Author(s):  
Chennan Yu ◽  
Jun Ye ◽  
Jiangming Jia ◽  
Xiong Zhao ◽  
Zhiwei Chen ◽  
...  
Keyword(s):  
Ankle Joint ◽  
Lower Limb ◽  
Gear Train ◽  
Home Healthcare ◽  
Dimensional Synthesis ◽  
Linkage Mechanism ◽  
Open Chain ◽  
Rehabilitation Training ◽  
Limb Rehabilitation ◽  
Lower Limb Rehabilitation

Abstract A foot-driven rehabilitation mechanism is suitable for home healthcare due to its advantages of simplicity, effectiveness, small size, and low price. However, most of the existing studies on lower limb rehabilitation movement only consider the trajectory of the ankle joint and ignore the influence of its posture angle, which makes it difficult to ensure the rotation requirements of the ankle joint and achieve a better rehabilitation effect. Aiming at the shortcomings of the current research, this paper proposes a new single degree-of-freedom (DOF) configuration that uses a noncircular gear train to constrain the three revolute joints (3R) open-chain linkage and expounds its dimensional synthesis method. Then, a parameter optimization model of the mechanism is established, and the genetic algorithm is used to optimize the mechanism parameters. According to the eight groups of key poses and position points of the ankle joint and the toe, the different configurations of the rehabilitation mechanism are synthesized and compared, and it is concluded that the newly proposed 3R open-chain noncircular gear-linkage mechanism exhibits better performance. Finally, combined with the requirements of rehabilitation training, a lower limb rehabilitation training device is designed based on this new configuration, and a prototype is developed and tested. The test results show that the device can meet the requirements of the key position points and posture angles of the ankle joint and the toe and verify the correctness of the proposed dimensional synthesis and optimization methods.

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