A double cylinders type traveling wave ultrasonic motor using composite transducer was proposed.The proposed stator contained two cylinders and one composite transducer,and the transducer located on the outer surfaces...A double cylinders type traveling wave ultrasonic motor using composite transducer was proposed.The proposed stator contained two cylinders and one composite transducer,and the transducer located on the outer surfaces of cylinders.The composite transducer included two exponential horns located on leading ends,and the horns insected with the cylinders at tip ends.Two degenerated flexural vibration modes spatially and temporally orthogonal to each other were excited in each cylinder by the composite transducer.In this new design,a single transducer could excite two flexural traveling waves in the cylinders.Thus,elliptical motions were achieved at the particles on the teeth.The working principle of the proposed motor was analyzed.The cylinder and transducer were designed with FEM.The resonant frequencies of two vibration modals of the stator were tuned to be the same,and the motion trajectories of nodes on the teeth were analyzed.Transient analysis results show that the motion trajectories of teeth are ellipses.The results of this paper can guide the development of this new type of ultrasonic motor.展开更多
Presents the mathematic model built for double stator permanent magnet synchronous motors through a brief analysis of their future development, and the equations established for calculation of their torques, and the d...Presents the mathematic model built for double stator permanent magnet synchronous motors through a brief analysis of their future development, and the equations established for calculation of their torques, and the development of prototypes, and discusses the comparison of the motor under development with the conventional motors with the same volume, stator structure, and magnet shape, and concludes the motor under development is one of the ways to improve the performance/volume ratio of motors.展开更多
A 44-year-old male who suffered a crush-degloving hand injury complicated by Complex Regional Pain Syndrome (CRPS) type I was scheduled for operative hand manipulation and inpatient physiotherapy. Preoperative placeme...A 44-year-old male who suffered a crush-degloving hand injury complicated by Complex Regional Pain Syndrome (CRPS) type I was scheduled for operative hand manipulation and inpatient physiotherapy. Preoperative placement of an ultrasound-guided infraclavicular catheter provided incomplete analgesia requiring supplemental morphine during physiotherapy sessions despite continuous infusion of 0.1% bupivacaine at 20 mL/hour. Due to the patient’s adamant refusal of replacement of the infraclavicular catheter, a second ultrasound-guided median nerve catheter was placed distally at the mid-forearm level and elicited complete sensory blockade of the hand. Dual infusions were maintained with 0.25% bupivacaine at 5 mL/hour through the median nerve catheter and 0.1% bupivacaine at 20 mL/hour through the infraclavicular catheter, and subsequent daily physiotherapy progressed productively. Continuous perineural catheter use to facilitate rehabilitation is an emerging practice that may improve overall recovery. Combination catheters, infusing local anesthetics at separate locations, can be used synergistically to preserve motor function and reach a superior analgesic endpoint.展开更多
In addition to the characteristics of a conventional motor, a novel direct-drive double-stator permanent-magnet brushless motor proposed can operate in the state of either a generator or a motor as appropriate. Throug...In addition to the characteristics of a conventional motor, a novel direct-drive double-stator permanent-magnet brushless motor proposed can operate in the state of either a generator or a motor as appropriate. Through numerical calculation and analysis, the output torque of double-stator permanent-magnet brushless motor of the same volume as the traditional machine is discussed, and the reduction of torque ripple by using the structure features of this motor is investigated. The results indicate that lower torque ripple under the condition of ideal effective torque can be obtained by the rational design of motor. The prototype motors tested show that this kind of motor structure has a higher power density.展开更多
A new-style direct drive motor with double-stator structure is proposed. The structure and principle of the permanent-magnet (PM) brushless motor are discussed. On the basis of numerical calculation, the cogging torqu...A new-style direct drive motor with double-stator structure is proposed. The structure and principle of the permanent-magnet (PM) brushless motor are discussed. On the basis of numerical calculation, the cogging torque waveforms of the prototype motor when staggering two stators are analyzed. The method that can reduce torque ripple making use of the structure features of this motor is investigated. The results of numerical calculation and experiment indicate that designing motor with this kind of structure is a good scheme for increasing the power density.展开更多
A new type of differential double-stator swing hydraulic motor,based on double stator structure,was introduced.Compared with the traditional swing hydraulic motors,it could provide various kinds of rotational speeds a...A new type of differential double-stator swing hydraulic motor,based on double stator structure,was introduced.Compared with the traditional swing hydraulic motors,it could provide various kinds of rotational speeds and torques under the same conditions of input flow rate and pressure.The operating principle and graphic symbols were described.The output speed and torque characters in multifarious connection modes were analyzed through single-acting differential double-stator swing hydraulic multi-motors.Then the differential connection modes and differential principles of differential double-stator swing hydraulic multi-motors were stated.Furthermore,the output speed and torque characters of doubleacting and triple-acting ones in multifarious connection modes were gotten.The interaction between output torque and the displacement ratio was studied.Finally,the internal leakage that influenced the volumetric efficiency was researched.The theoretical and experimental researches show that the differential double-stator swing hydraulic multi-motors can provide various kinds of rotational speeds and torques.Predictably,this new kind of swing hydraulic multi-motors has broad application prospects in machine tool equipments,engineering machineries,and simulation turntables.展开更多
Recently,there is an increasing requirement for controlling linear motion up to a few hundred of millimeter strokes in the area of the liquid crystal display(LCD) production equipment.The requirements of the motion sy...Recently,there is an increasing requirement for controlling linear motion up to a few hundred of millimeter strokes in the area of the liquid crystal display(LCD) production equipment.The requirements of the motion system for LCD production equipment are high acceleration and high velocity with positioning accuracy.To satisfy these requirements,it has to be designed with the high-thrust force and low velocity ripple.In this work, high-thrust and double-sided linear synchronous motor (LSM)module is proposed and the developed high-thrust and double-sided LSM module is verified by performance test.展开更多
Due to the influence of material characteristics and winding power, single output electromagnet has limited ability to improve the dynamic characteristic of electro-hydraulic valve. Therefore, an electromechanical con...Due to the influence of material characteristics and winding power, single output electromagnet has limited ability to improve the dynamic characteristic of electro-hydraulic valve. Therefore, an electromechanical converter with double push rods is proposed in this paper, which can simultaneously output two electromagnetic forces, can push or pull the valve core and sleeve according to the current direction and realize rapid operation of load. According to the electromagnetic principle and the magnetic circuit analysis method, the mathematical model and equivalent circuit of the electromechanical converter with double push rods are established. Through the finite element simulation model of the electromechanical converter with double push rods with the same magnetization directions, the changing rules of its magnetic field distribution and force–displacement behaviors are studied and analyzed. According to the analysis results, the electromagnetic mechanical parameters and mechanical structure of the electromechanical converter with double push rods are determined, and the prototype is made. The test platform for the push-pull characteristics of the electromechanical converter with double push rods is built, and its static and dynamic characteristics are tested and analyzed. The results show that the thrust and pull output characteristics of the internal and external push rods are basically consistent with the simulation output, and proportional to the current density of the coil;the push-pull hysteresis of internal and external push rods output force is less than 5%;and the dynamic time response characteristics of the displacement and force are obtained. The hysteresis e ect of output force is improved e ectively through the H bridge drive control circuit modulated by PWM. Compared with the displacement response of a singlewinding electromagnet with a similar volume, it can e ectively improve the dynamic displacement response. Followup work will further optimize the structure of the electromechanical converter and test the corresponding pilot valve. The research results provide a new theory for improving the output characteristics of electro-hydraulic pilot valve and have an extremely high engineering application value and broad application prospect.展开更多
基金Sponsored by the National Natural Science Foundation of China (Grant No. 50875057 and 51075082)the State Key Laboratory of Robotics and Systems (HIT No. SKLRS200901A04)
文摘A double cylinders type traveling wave ultrasonic motor using composite transducer was proposed.The proposed stator contained two cylinders and one composite transducer,and the transducer located on the outer surfaces of cylinders.The composite transducer included two exponential horns located on leading ends,and the horns insected with the cylinders at tip ends.Two degenerated flexural vibration modes spatially and temporally orthogonal to each other were excited in each cylinder by the composite transducer.In this new design,a single transducer could excite two flexural traveling waves in the cylinders.Thus,elliptical motions were achieved at the particles on the teeth.The working principle of the proposed motor was analyzed.The cylinder and transducer were designed with FEM.The resonant frequencies of two vibration modals of the stator were tuned to be the same,and the motion trajectories of nodes on the teeth were analyzed.Transient analysis results show that the motion trajectories of teeth are ellipses.The results of this paper can guide the development of this new type of ultrasonic motor.
文摘Presents the mathematic model built for double stator permanent magnet synchronous motors through a brief analysis of their future development, and the equations established for calculation of their torques, and the development of prototypes, and discusses the comparison of the motor under development with the conventional motors with the same volume, stator structure, and magnet shape, and concludes the motor under development is one of the ways to improve the performance/volume ratio of motors.
文摘A 44-year-old male who suffered a crush-degloving hand injury complicated by Complex Regional Pain Syndrome (CRPS) type I was scheduled for operative hand manipulation and inpatient physiotherapy. Preoperative placement of an ultrasound-guided infraclavicular catheter provided incomplete analgesia requiring supplemental morphine during physiotherapy sessions despite continuous infusion of 0.1% bupivacaine at 20 mL/hour. Due to the patient’s adamant refusal of replacement of the infraclavicular catheter, a second ultrasound-guided median nerve catheter was placed distally at the mid-forearm level and elicited complete sensory blockade of the hand. Dual infusions were maintained with 0.25% bupivacaine at 5 mL/hour through the median nerve catheter and 0.1% bupivacaine at 20 mL/hour through the infraclavicular catheter, and subsequent daily physiotherapy progressed productively. Continuous perineural catheter use to facilitate rehabilitation is an emerging practice that may improve overall recovery. Combination catheters, infusing local anesthetics at separate locations, can be used synergistically to preserve motor function and reach a superior analgesic endpoint.
文摘In addition to the characteristics of a conventional motor, a novel direct-drive double-stator permanent-magnet brushless motor proposed can operate in the state of either a generator or a motor as appropriate. Through numerical calculation and analysis, the output torque of double-stator permanent-magnet brushless motor of the same volume as the traditional machine is discussed, and the reduction of torque ripple by using the structure features of this motor is investigated. The results indicate that lower torque ripple under the condition of ideal effective torque can be obtained by the rational design of motor. The prototype motors tested show that this kind of motor structure has a higher power density.
文摘A new-style direct drive motor with double-stator structure is proposed. The structure and principle of the permanent-magnet (PM) brushless motor are discussed. On the basis of numerical calculation, the cogging torque waveforms of the prototype motor when staggering two stators are analyzed. The method that can reduce torque ripple making use of the structure features of this motor is investigated. The results of numerical calculation and experiment indicate that designing motor with this kind of structure is a good scheme for increasing the power density.
基金National Natural Science Foundation of China(No.50975246)
文摘A new type of differential double-stator swing hydraulic motor,based on double stator structure,was introduced.Compared with the traditional swing hydraulic motors,it could provide various kinds of rotational speeds and torques under the same conditions of input flow rate and pressure.The operating principle and graphic symbols were described.The output speed and torque characters in multifarious connection modes were analyzed through single-acting differential double-stator swing hydraulic multi-motors.Then the differential connection modes and differential principles of differential double-stator swing hydraulic multi-motors were stated.Furthermore,the output speed and torque characters of doubleacting and triple-acting ones in multifarious connection modes were gotten.The interaction between output torque and the displacement ratio was studied.Finally,the internal leakage that influenced the volumetric efficiency was researched.The theoretical and experimental researches show that the differential double-stator swing hydraulic multi-motors can provide various kinds of rotational speeds and torques.Predictably,this new kind of swing hydraulic multi-motors has broad application prospects in machine tool equipments,engineering machineries,and simulation turntables.
基金supported by the ministry of education,science technology [MEST] and the ministry of knowledge economy [MKE] through the fostering project of the industrial-academic cooperation centered university.
文摘Recently,there is an increasing requirement for controlling linear motion up to a few hundred of millimeter strokes in the area of the liquid crystal display(LCD) production equipment.The requirements of the motion system for LCD production equipment are high acceleration and high velocity with positioning accuracy.To satisfy these requirements,it has to be designed with the high-thrust force and low velocity ripple.In this work, high-thrust and double-sided linear synchronous motor (LSM)module is proposed and the developed high-thrust and double-sided LSM module is verified by performance test.
基金Supported by National Natural Science Foundation for Young Scientists of China(Grant No.51505317)Shanxi Provincial Natural Science Foundation of China(Grant No.201601D102039)
文摘Due to the influence of material characteristics and winding power, single output electromagnet has limited ability to improve the dynamic characteristic of electro-hydraulic valve. Therefore, an electromechanical converter with double push rods is proposed in this paper, which can simultaneously output two electromagnetic forces, can push or pull the valve core and sleeve according to the current direction and realize rapid operation of load. According to the electromagnetic principle and the magnetic circuit analysis method, the mathematical model and equivalent circuit of the electromechanical converter with double push rods are established. Through the finite element simulation model of the electromechanical converter with double push rods with the same magnetization directions, the changing rules of its magnetic field distribution and force–displacement behaviors are studied and analyzed. According to the analysis results, the electromagnetic mechanical parameters and mechanical structure of the electromechanical converter with double push rods are determined, and the prototype is made. The test platform for the push-pull characteristics of the electromechanical converter with double push rods is built, and its static and dynamic characteristics are tested and analyzed. The results show that the thrust and pull output characteristics of the internal and external push rods are basically consistent with the simulation output, and proportional to the current density of the coil;the push-pull hysteresis of internal and external push rods output force is less than 5%;and the dynamic time response characteristics of the displacement and force are obtained. The hysteresis e ect of output force is improved e ectively through the H bridge drive control circuit modulated by PWM. Compared with the displacement response of a singlewinding electromagnet with a similar volume, it can e ectively improve the dynamic displacement response. Followup work will further optimize the structure of the electromechanical converter and test the corresponding pilot valve. The research results provide a new theory for improving the output characteristics of electro-hydraulic pilot valve and have an extremely high engineering application value and broad application prospect.