Lead zirconate titanium solid-solution (PZT) thin films with variousthickness are synthesized on titanium substrates by repeated hydrothermal treatments. Young modulus,electric-field-induced displacement and the densi...Lead zirconate titanium solid-solution (PZT) thin films with variousthickness are synthesized on titanium substrates by repeated hydrothermal treatments. Young modulus,electric-field-induced displacement and the density of the PZT film are measured respectively.Bimorph- type bending actuators are fabricated using these films. The model, which is used toanalyze the driving ability of bimorph-type bending actuators by hydrothermal method, is set up. Itcan be seen that the driving ability of bimorph-type bending actuators can be greatly improved byoptimizing the thickness of PZT thin film and substrate from the theoretical analysis results. Themeasured values are expected to agree with the theoretical values calculated by the above model.展开更多
We investigated bending moment resistance under diagonal compression load of comer doweled joints with plywood members. Joint members were made of ll-ply hardwood plywood of 19 mm thickness. Dowels were fabricated of ...We investigated bending moment resistance under diagonal compression load of comer doweled joints with plywood members. Joint members were made of ll-ply hardwood plywood of 19 mm thickness. Dowels were fabricated of Beech and Hornbeam species. Their diameters （6, 8 and 10 mm） and depths of penetration （9, 13 and 17 ram） in joint members were chosen variables in our experiment. By increasing the connector＇s diameter from 6 to 8 mm, the bending moment resistance under diagonal compressive load was increased, while it decreased when the diameter was increased from 8 to 10 mm. The bending moment re- sistance under diagonal compressive load was increased by increasing the dowel＇s depth of penetration. Joints made with dowels of Beech had higher resistance than dowels of Hornbeam. Highest resisting moment （45.18 N.m） was recorded for joints assembled with 8 mm Beech dowels penetrating 17 mm into joint members Lowest resisting moment （13.35 N.m） was recorded for joints assembled with 6 mm Hornbeam dowels and penetrating 9 mm into joint members.展开更多
We determined the effects of the penetration depth and spline material and composite material type as well as joining method on bending moment resistance under diagonal compression and tension in common wood panel str...We determined the effects of the penetration depth and spline material and composite material type as well as joining method on bending moment resistance under diagonal compression and tension in common wood panel structures. Composite materials were laminated medium density fiberboard （MDF） and particleboard. Joining methods were butt and miter types. Spline materials were high density fiberboard （HDF）. The penetration depths of plywood, wood （Carpinus betolus） and spline were 8, 11 and 14 mm. The results showed that in both diagonal com- pression and tension, MDF joints are stronger than particleboard joints, and the bending moment resistance under compression is higher compared with that in tension. The highest bending moment resistance under tension was shown in MDF, butt joined using plywood spline with 8 mm penetration depth, whereas under compression bending moment resistance was seen in MDF, miter joined with the HDF spline of 14 mm penetration depth.展开更多
This study is to explore a composite type piezoelectric motor. Its main structures include the piezoelectric stator, rotor, the preload adjusting module and shaft. Wherein the piezoelectric stator is made base, the co...This study is to explore a composite type piezoelectric motor. Its main structures include the piezoelectric stator, rotor, the preload adjusting module and shaft. Wherein the piezoelectric stator is made base, the composite type actuating element and stator formed. As the composite type actuating element is set by the axial vibration type actuating element, horizontal bending vibration type actuating element and vertical bending vibration type actuating element formed. The stator is an empty cylinder with a waist and tapered hole. In addition, the rotor is a kind of a hollow cone. It can be through the preload adjusting module to withstand the stator. As the preload adjusting module is set by the limit element, spring, washer and nut formed. While the shaft is a kind of cylinder with screw thread and stopper, it can pass through the piezoelectric stator, rotor and the preload adjusting module, making it a composite type piezoelectric motor. When we provide appropriate driving voltage, frequency, loading and phase angle to the piezoelectric stator, we can let the piezoelectric motor produces rapid rotation. Of course, we can also change through the driving phase angle, to change the direction of rotation of the piezoelectric motor. According to the experimental results, we found that its maximum speed and loading are 480 rpm and 2305 gw under conditions of 180 Vp-p, 35 kHz and 00 driving phase angle. Most importantly, we also found that the composite type piezoelectric motor has a very good conversion efficiency of the driving phase angle.展开更多
By using transfer matrix,the lower-order natural frequencies of the Watt type planar six-barlinkage are calculated in this paper.The experiment of the modal analysis is done with the SignalProcessor 7T17S,and the expe...By using transfer matrix,the lower-order natural frequencies of the Watt type planar six-barlinkage are calculated in this paper.The experiment of the modal analysis is done with the SignalProcessor 7T17S,and the experiment results agree with the calculated ones.This method only re-quires calculation of lower-order transfer matrix and determinant values,so that, it can be done ona minicomputer such as IBM/PC.The method adopted in this paper is also suitable for vibrationanalysis of other types of linkages.展开更多
基金This project is supported by National Natural Science Foundation of China(No.90207003) and Returnee Foundation of Dalian.
文摘Lead zirconate titanium solid-solution (PZT) thin films with variousthickness are synthesized on titanium substrates by repeated hydrothermal treatments. Young modulus,electric-field-induced displacement and the density of the PZT film are measured respectively.Bimorph- type bending actuators are fabricated using these films. The model, which is used toanalyze the driving ability of bimorph-type bending actuators by hydrothermal method, is set up. Itcan be seen that the driving ability of bimorph-type bending actuators can be greatly improved byoptimizing the thickness of PZT thin film and substrate from the theoretical analysis results. Themeasured values are expected to agree with the theoretical values calculated by the above model.
文摘We investigated bending moment resistance under diagonal compression load of comer doweled joints with plywood members. Joint members were made of ll-ply hardwood plywood of 19 mm thickness. Dowels were fabricated of Beech and Hornbeam species. Their diameters （6, 8 and 10 mm） and depths of penetration （9, 13 and 17 ram） in joint members were chosen variables in our experiment. By increasing the connector＇s diameter from 6 to 8 mm, the bending moment resistance under diagonal compressive load was increased, while it decreased when the diameter was increased from 8 to 10 mm. The bending moment re- sistance under diagonal compressive load was increased by increasing the dowel＇s depth of penetration. Joints made with dowels of Beech had higher resistance than dowels of Hornbeam. Highest resisting moment （45.18 N.m） was recorded for joints assembled with 8 mm Beech dowels penetrating 17 mm into joint members Lowest resisting moment （13.35 N.m） was recorded for joints assembled with 6 mm Hornbeam dowels and penetrating 9 mm into joint members.
文摘We determined the effects of the penetration depth and spline material and composite material type as well as joining method on bending moment resistance under diagonal compression and tension in common wood panel structures. Composite materials were laminated medium density fiberboard （MDF） and particleboard. Joining methods were butt and miter types. Spline materials were high density fiberboard （HDF）. The penetration depths of plywood, wood （Carpinus betolus） and spline were 8, 11 and 14 mm. The results showed that in both diagonal com- pression and tension, MDF joints are stronger than particleboard joints, and the bending moment resistance under compression is higher compared with that in tension. The highest bending moment resistance under tension was shown in MDF, butt joined using plywood spline with 8 mm penetration depth, whereas under compression bending moment resistance was seen in MDF, miter joined with the HDF spline of 14 mm penetration depth.
文摘This study is to explore a composite type piezoelectric motor. Its main structures include the piezoelectric stator, rotor, the preload adjusting module and shaft. Wherein the piezoelectric stator is made base, the composite type actuating element and stator formed. As the composite type actuating element is set by the axial vibration type actuating element, horizontal bending vibration type actuating element and vertical bending vibration type actuating element formed. The stator is an empty cylinder with a waist and tapered hole. In addition, the rotor is a kind of a hollow cone. It can be through the preload adjusting module to withstand the stator. As the preload adjusting module is set by the limit element, spring, washer and nut formed. While the shaft is a kind of cylinder with screw thread and stopper, it can pass through the piezoelectric stator, rotor and the preload adjusting module, making it a composite type piezoelectric motor. When we provide appropriate driving voltage, frequency, loading and phase angle to the piezoelectric stator, we can let the piezoelectric motor produces rapid rotation. Of course, we can also change through the driving phase angle, to change the direction of rotation of the piezoelectric motor. According to the experimental results, we found that its maximum speed and loading are 480 rpm and 2305 gw under conditions of 180 Vp-p, 35 kHz and 00 driving phase angle. Most importantly, we also found that the composite type piezoelectric motor has a very good conversion efficiency of the driving phase angle.
文摘By using transfer matrix,the lower-order natural frequencies of the Watt type planar six-barlinkage are calculated in this paper.The experiment of the modal analysis is done with the SignalProcessor 7T17S,and the experiment results agree with the calculated ones.This method only re-quires calculation of lower-order transfer matrix and determinant values,so that, it can be done ona minicomputer such as IBM/PC.The method adopted in this paper is also suitable for vibrationanalysis of other types of linkages.
