Gerotor pump is a special kind of internal rotary pump, which contains a trochoid profile (commonly called as cycloid). Generation of trochoid is normally realized by external rolling method, namely a circle rotating ...Gerotor pump is a special kind of internal rotary pump, which contains a trochoid profile (commonly called as cycloid). Generation of trochoid is normally realized by external rolling method, namely a circle rotating on a fixed circle without slipping. This paper proposes derivative process of the trochoid profile by means of internal rolling method, which is that internal surface of a circle contacts with a fixed circle and rotates around it without slipping. Moreover the instantaneous flow rate can be obtained by numerically calculating the change ratio of area between the inner and outer rotors in the outlet region of the gerotor pump, which avoids to complicatedly derivative process.展开更多
We investigated a series of novel motors and pumps with a new structure called double-stator. Double-stator can be used as pump or motor just for the working condition on demand. A certain amount of pumps or motors ar...We investigated a series of novel motors and pumps with a new structure called double-stator. Double-stator can be used as pump or motor just for the working condition on demand. A certain amount of pumps or motors are formed in one shell and these subpumps or submotors can work alone or in company without influence on other pumps or moters. This kind of double-stator pumps (motors) are called multi-pumps (multi-motors). Through the analysis of multifarious connection modes of single-acting double-stator multi-pumps and multi-motors, the mathematical expressions of output flow rate, rotational speed and torque are acquired. The results indicate that different flow rates can be provided by one fixed displacement double-stator multi-pump system under the condition of an unalterable driven speed. Likewise, under the terms of a fixed input flow and without complex variable mechanisms, the functions of double speeds, multiple speeds and even differential connection can be realized by a double-stator multi-motor system with various output rotational speeds and torques.展开更多
Due to the limited output capability of piezoelectric diaphragm pumps, the driving voltage is frequently increased to obtain the desired output. However, the excessive voltage application may lead to a large deformati...Due to the limited output capability of piezoelectric diaphragm pumps, the driving voltage is frequently increased to obtain the desired output. However, the excessive voltage application may lead to a large deformation in the piezoelectric ceramics, which could cause it to breakdown or become damaged. Therefore, increasing the number of chambers to obtain the desired output is proposed. Using a check-valve quintuple-chamber pump with quintuple piezoelectric actuators, the characteristics of the pump under different driving modes are investigated through experiments. By changing the number and connection mode of working actuators, pump performances in terms of flow rate and backpressure are tested at a voltage of 150 V with a frequency range of 60 Hz -400 Hz. Experiment results indicate that the properties of the multiple-chamber pump change significantly with distinct working chambers even though the number of pumping chambers is the same. Pump performance declines as the distance between the working actuators increases. Moreover, pump performance declines dramatically when the working piezoelectric actuator closest to the outlet is involved. The maximum backpressures of the pump with triple, quadruple, and quintuple actuators are increased by 39%, 83%, and 128%, respectively, compared with the pump with double working actuators; the corresponding maximum flow rates of the pumps are simply increased by 25.9%, 49.2%, and 67.8%, respectively. The proposed research offers practical guidance for the effective utilization of the multiple-chamber pumps under different driving modes.展开更多
文摘Gerotor pump is a special kind of internal rotary pump, which contains a trochoid profile (commonly called as cycloid). Generation of trochoid is normally realized by external rolling method, namely a circle rotating on a fixed circle without slipping. This paper proposes derivative process of the trochoid profile by means of internal rolling method, which is that internal surface of a circle contacts with a fixed circle and rotates around it without slipping. Moreover the instantaneous flow rate can be obtained by numerically calculating the change ratio of area between the inner and outer rotors in the outlet region of the gerotor pump, which avoids to complicatedly derivative process.
基金Funded by the National Natural Science Foundation of China (No. 50975246)
文摘We investigated a series of novel motors and pumps with a new structure called double-stator. Double-stator can be used as pump or motor just for the working condition on demand. A certain amount of pumps or motors are formed in one shell and these subpumps or submotors can work alone or in company without influence on other pumps or moters. This kind of double-stator pumps (motors) are called multi-pumps (multi-motors). Through the analysis of multifarious connection modes of single-acting double-stator multi-pumps and multi-motors, the mathematical expressions of output flow rate, rotational speed and torque are acquired. The results indicate that different flow rates can be provided by one fixed displacement double-stator multi-pump system under the condition of an unalterable driven speed. Likewise, under the terms of a fixed input flow and without complex variable mechanisms, the functions of double speeds, multiple speeds and even differential connection can be realized by a double-stator multi-motor system with various output rotational speeds and torques.
基金Supported by National Natural Science Foundation of China(Grant Nos.51205366,51205367,51377147)Zhejiang Provincial Natural Science Foundation of China(Grant No.LQ13E050007)
文摘Due to the limited output capability of piezoelectric diaphragm pumps, the driving voltage is frequently increased to obtain the desired output. However, the excessive voltage application may lead to a large deformation in the piezoelectric ceramics, which could cause it to breakdown or become damaged. Therefore, increasing the number of chambers to obtain the desired output is proposed. Using a check-valve quintuple-chamber pump with quintuple piezoelectric actuators, the characteristics of the pump under different driving modes are investigated through experiments. By changing the number and connection mode of working actuators, pump performances in terms of flow rate and backpressure are tested at a voltage of 150 V with a frequency range of 60 Hz -400 Hz. Experiment results indicate that the properties of the multiple-chamber pump change significantly with distinct working chambers even though the number of pumping chambers is the same. Pump performance declines as the distance between the working actuators increases. Moreover, pump performance declines dramatically when the working piezoelectric actuator closest to the outlet is involved. The maximum backpressures of the pump with triple, quadruple, and quintuple actuators are increased by 39%, 83%, and 128%, respectively, compared with the pump with double working actuators; the corresponding maximum flow rates of the pumps are simply increased by 25.9%, 49.2%, and 67.8%, respectively. The proposed research offers practical guidance for the effective utilization of the multiple-chamber pumps under different driving modes.
