Recent Patents on Mechanical Engineering - Volume 10, Issue 3, 2017

Background: With the increasing number of hemiplegic patients in recent years, traditional rehabilitation methods cannot meet the current social needs. In order to help patients recover as soon as possible, the combination of the human intelligence and the mechanical power device of the manmachine interface of the exoskeletal rehabilitation robot is becoming more and more popular. Objective: To provide an overview of recent exoskeletal rehabilitation robot for upper limb and introduce their respective characteristics and development. Methods: This paper reviews various representative patents related to the exoskeletal rehabilitation robot for upper limb. The structural characteristics and applications of the typical exoskeletal rehabilitation robots for upper limb are introduced. Results: Different types of exoskeletal rehabilitation robots for upper limb are enumerated, and different characteristics of them are analyzed. The existing problems of exoskeletal rehabilitation robots for upper limb are summarized, and the current development including future of patents on exoskeletal rehabilitation robots for upper limb are discussed. Conclusion: The optimization of the structure and performance of the exoskeletal rehabilitation robots for upper limb greatly improves the efficiency of rehabilitation. For further development, more and more patents on exoskeletal rehabilitation robots for upper limb should be designed and invented.

Background: The organic Rankine cycle (ORC) has been proved as a potential technique for internal combustion engine waste heat recovery (ICE-WHR), which efficiently increase the ICE conversion efficiency. Objective: This paper presents an overview of five advanced novel ORC architectures that are most commonly discussed in the recent decades. Based on the recent patent list, some novel ORC components are also overviewed by the authors. Methods: The five advanced ORC architectures are briefly introduced compared with the architecture of basic ORC. The mentioned architectures are categorized into two types: The first four, such as the ORC with recuperator and the supercritical ORC, aim at improving system performance, while the last enhances the ICE aftertreatment performance. Besides, their thermodynamic characters are analyzed based on the efficiency-oriented or output-power oriented evaluation criteria. According to the recent patent list, some novel ORC components, such as a high-efficiency ensuring variable expansion ratio rotary vane expander, an integrated function reciprocating single work shaft element, are also overviewed by the authors. The typical patents of novel ORC components are overviewed by concisely introducing their mechanical structure and working principle. Results: An overview of five advanced novel ORC architectures are presented. Besides, on the basis of the recent patent list, several novel ORC components are introduced. Conclusion: The first type of the advanced ORC systems improves ORC performance, while the second type also enhances the automotive after treatment system performance. Furthermore, the novel ORC components are recommended to be installed in the ORC system for future use.

Background: An effective method of enlarging grease application fields is to improve its lubricant behavior by adding reinforced particle. This paper reviews various recent patents on nanoparticle as additive phase to improve lubrication performance. Objective: To provide an overview on the effect of various amounts of ZnO nanoparticles on the tribological behavior of lubricant grease. Methods: By means of a friction and wear testing machine, the tribological behavior of lubricant grease containing ZnO nanoparticles on a range from 1 to 1.8wt.% was investigated in detail. Results: Results show that the lubricant properties of nanoadditive based grease containing 1.2wt.% ZnO nanoparticles possessed the smallest friction coefficient and wear scar diameter in all experiments. It was determined that during the course of friction, the additive amount of 1.2wt.% promoted the deposition of ZnO nanoparticles and effectively repaired wear scar morphology, which led to less wear on the ball-disc frictional pair. Conclusion: The list of patents reviewed here is by no means supposed to be completed or extensive but shows evolution trends concerning latent nano-lubrication.

Background: Patient transferring device is designed to transfer patients with spinal cord injury, severe burn injury, infectious diseases or other critical injury especially, between operating bed and hospital bed. Its purpose is to carry patients safely, painlessly and without secondary injury, and to reduce the labor intensity of nursing staff and the threat of infection. Objective: To promote the development of patient transferring device in clinic, provide an overview of recent patient transport devices and introduce their respective characteristics and development trends. Methods: This paper reviews various representative patents related to patient transferring device. The structural characteristics and applications of the typical patient transferring device are introduced. Results: The differences of different types of patient transferring devices are compared and analyzed, and the structural characteristics are concluded. The main problems in its development are analyzed, the development trend is foreseen, and the current and future research of the patents on patient transferring device is discussed. Conclusion: Patient transferring device has important practical significance, and plays an important role in promoting the technology innovation in medical machine automation. And the reliability, intelligence and safety of the patient transferring device need to be further improved. More patents on patient transferring device should be invented.

Background: Hydraulic powered support is a vital equipment of integrated mechanized mining face, used for the protection of people in coal mine underground. Its performance affects the working condition of the whole working face directly. Objective: To improve the its design efficiency and compensate for the lack of experience in designing column, the patent of the Hydraulic Column Design System is designed to provide an optimized model by the expert system according to the operating condition and help designers to finish the cylinder design rapidly and easily. Methods: The patent of analysis system contains a user interface, three kinds of databases and several message responses. The user interface was developed based on the Visual C++ environment. The databases were written in C++ and APDL language which include three databases that are calculation, selection and strength check databases. Besides, to improve the accuracy of design, finite element analysis has been adopted in the system which is run through interface program and completes the stress analysis automatically. Results: Stability and strength analysis on the 8.2m hydraulic support designed by the system showed that the diameters and lengths of the designed cylinders in accord with the national standard and the requirements of movement. The maximum stress exerts on the joint of outer cylinder and middle cylinder and the maximum stress value is 659Mpa which is smaller than the material strength 1170Mpa. Conclusion: The hydraulic column design system is better suited for hydraulic column design. The designed size of column varies from 180mm to 760mm. Meanwhile, by verification, only one point five hours are needed to finish the same work with the system and it can save 94.5% time compared to the traditional method on column design in the same condition effectively.

Background: This patent is based on the combination of caterpillar mechanisms and conveyors. Caterpillar tracks support heavy loads and adapt this support according to the ground conditions. Conveyors displace distributed loads continuously and bidirectionally using the force of friction. This paper describes a revision of previous patents related to this innovative design. Objective: This paper presents an innovative patent to continuously displace heavy structures safely. The mechanism was patented in 2011 as Spanish Patent ES2367737. The combination of these mechanisms provides the design of this patent to displace heavy structures continuously and bidirectionally, while adapting to the deflection of the structures. Methods: The most important elements of this patent are detailed in the paper. The most innovative component is the load compensation system, which increases the safety of the displacement of heavy structures. This system controls the load applied on the mechanism, and the displacement can be stopped before the collapse of the heavy structure. Results: An application of the patent for launching bridges using the Incremental Launching Method is presented. This mechanism is used to displace heavy structures using the force of friction. Conclusion: The patented mechanism is an original contribution for the displacement of heavy structures continuously and bidirectionally. The patent can be used to launch bridges, improving the efficiency, sustainability, and safety of current systems.

Background: The present paper is focused on the numerical investigation of the effects of temperature dependent viscosity and temperature-dependent thermal conductivity on steady, free convection flow of a viscous incompressible fluid in a vertical rectangular duct. Objectives: The purpose of this study was to provide an overview of the flow field if one assumes that viscosity and thermal conductivity parameters are not constant but they depend on the temperature. Methods: Finite difference scheme of second order accuracy was applied to solve the two dimensional coupled nonlinear equations. Validity of the obtained results was justified with the literature. Results: The effects of the non-dimensional parameters such as variable viscosity, variable thermal conductivity, Grashof number, Brinkman number and aspect ratio on the velocity, temperature, shear stress, volumetric flow rate and heat transfer rate were evaluated and depicted pictorially and also in the form of tables. It was observed that the effects of variable viscosity and thermal conductivity on the velocity and temperature fields were significant. Conclusion: It has been concluded that for positive values of the viscosity and conductivity variation parameters, the viscous fluid flows in the upward direction and for negative values, the fluid flows in the downward direction of the duct. Increase in the viscosity variation parameter, the thermal conductivity variation parameter, Grashof number, Brinkman number and the aspect ratio resulted in the improvement of the volumetric flow rate.

Background: Microelectrodes have been widely used in the fields of microfabrication, measurement and medical applications. Electrochemical etching machining is a better method for fabricating microelectrode, and the multi-stepped electrode is easily fabricated to very small size. However, the rotary accuracy of multi-stepped electrode fabricated by conventional electrochemical etching is not high, because of the installation error of electrode and the uneven machining gap between the electrode and tool cathode. Various relevant papers and patents have studied different methods to improve the machining accuracy and efficiency of electrodes. Objective: In order to achieve the high-efficiency machining of multi-stepped cylindrical microelectrode with high rotary accuracy, a new electrochemical etching process (rotating electrochemical etching) is introduced. Methods: Firstly, the effect of machining current on the change of electrode diameter was deduced based on the principle of electrochemical etching. Secondly, the experiments proved that the rotation can improve the current change rate and the effective initial current and thus improve the machining efficiency. Following this, the influence of rotation on the rotary accuracy of electrode was analyzed, and the efficient method, which uses different rotation speeds combination, was proposed to fabricate multi-stepped cylindrical microelectrodes with high rotary accuracy. Thirdly, the influence of machining parameters such as the rotation speed, the voltage and the cut-off current, on the shape and size of electrode was analyzed. Results: Finally, a set of three-stepped cylindrical microelectrodes, which have the terminal diameter of less than 15μm and coaxial error within 1μm, was successfully fabricated using the optimized machining parameters. Compared with the conventional electrochemical etching process, the machining efficiency improved significantly. Conclusion: It has been proved that rotating electrochemical etching is a better method to improve the machining efficiency and rotary accuracy of microelectrodes.

Background: Many swimming micro-robots inspired by bacteria, could be used for different medical applications including Nano-drugs delivery, micro surgery and minimally invasive diagnostic. More patents on micro-robots for medical applications should be invented. Some research teams work to design and produce micro-swimming-robots inspired by bacteria. Objective: The purpose of this study was to simulate flagella motion. Also for better designs, the effects of the geometrical ratios of flagellum on the non-dimensional propulsive force and nondimensional velocity have been studied. Methods: Bacterium as a kind of micro-organisms has an appropriate propulsive mechanism to be inspired in medical applications. Flagella's helical motion creates a propulsive force and thus causes the motion. We have simulated the dynamic of the propulsion mechanism of flagella using finite element method. Flagella have been simulated in a long tube with a finite radius. Results: For future patents design, the effects of the geometrical ratios of flagellum on the nondimensional propulsive force and non-dimensional velocity have been studied. We have validated our results with the results from experiment and Slender Body Theory. Conclusion: In future, swimming micro-robots will be important tools in medicine. There are some patents in this field. It was concluded that to reach maximum propulsive force, optimized ratios of geometrical parameters should be used.