PERFORMANCE OF MICRO-INJECTOR WITH INNER BLOCK FOR DROP ON DEMAND APPLICATIONS

2010 ◽  
Vol 24 (13) ◽  
pp. 1373-1376
Author(s):  
MUH-RONG WANG ◽  
TZONG-SHYNG LEU ◽  
YI-JUN SHEN ◽  
WEI-LUNG WENG
Keyword(s):  
Piezoelectric Actuator ◽  
Driving Voltage ◽  
Driving Frequency ◽  
On Demand ◽  
Micro Nozzle ◽  
Drop On Demand ◽  
Flow Through ◽  
The One ◽  
Instability Energy ◽  
Better Than

This paper investigates the characteristics of a piezoelectric micro-injector for drop-on-demand (DOD) applications. The micro-injector is designed with an inner block inside the chamber to enhance the instability energy for the production of mono-size droplet. The micro-nozzle was fabricated by MEMS processes. The upper chip is a silicon chip with two holes as the inlet and outlet of the liquid matter. A diaphragm is mounted on the center of the upper chip. The lower chip has an orifice of 50µm in diameter. The flow through the chamber is used to promote the refilling mechanism for droplet generation. A piezoelectric actuator operated in push mode (D33) was mounted on the upper chip to drive the liquid through the nozzle. An inner block is designed on the inner side of the upper chip. Results show that the micro-injector with inner block could generate mono-size droplet under the driving voltage ranging from 62.5 to 150 volt at frequency of 3.2 kHz. The droplets size was 60µm with velocity ranging from 3.3 to 4.7 m/s which is higher than the case without inner block. As a comparison, the injection of the micro-injector without inner block needs a much higher driving voltage of 112.5 volt at driving frequency of 9.7kHz. It is concluded that the micro-injector with the inner block performs better than the one without the inner block.

scholarly journals A Novel Impact Rotary–Linear Motor Based on Decomposed Screw-Type Motion of Piezoelectric Actuator

2018 ◽  
Vol 8 (12) ◽  
pp. 2492
Author(s):  
Liling Han ◽  
Liandong Yu ◽  
Chengliang Pan ◽  
Huining Zhao ◽  
Yizhou Jiang
Keyword(s):  
Piezoelectric Actuator ◽  
Degree Of Freedom ◽  
Rotary Motion ◽  
Maximum Diameter ◽  
Torsional Angle ◽  
Driving Voltage ◽  
Driving Frequency ◽  
Linear Motion ◽  
Longitudinal Displacement ◽  
Two Degree Of Freedom

A novel impact two-degree-of-freedom (2-DOF) motor based on the decomposed screw-type motion of a piezoelectric actuator (PA) has been proposed. The fabricated prototype motor has a maximum diameter of 15 mm and a length of 100 mm which can produce a maximum torsional angle of about 1000 μrad and a maximum longitudinal displacement of about 1.03 μm under a saw-shaped driving voltage with 720 Vp-p (peak-to-peak driving voltage). When the axial prepressure generated by the spring is about 1N and the radial prepressure generated by the snap ring is about 14 N, the fabricated motor realizes rotary motion with the driving frequency from 200 Hz to 4 kHz. When the axial prepressure generated by the spring is about 11.7 N and the radial prepressure generated by the snap ring is about 21.1 N, the fabricated motor realizes linear motion with the driving frequency from 2 kHz to 11 kHz. In the experiments, the prototype motor can achieve 9.9 × 105 μrad/s rotary velocity at 2 kHz and it can achieve 2.4 mm/s linear velocity at 11 kHz under the driving voltage of 720 Vp-p.

Energy Analysis of Piezoelectric-Actuated Structures Driven by Linear Amplifiers

1999 ◽  
Author(s):  
Donald J. Leo
Keyword(s):  
Energy Dissipation ◽  
Piezoelectric Actuator ◽  
Supply Voltage ◽  
Mechanical Load ◽  
Minimum Energy ◽  
Electromechanical System ◽  
Driving Voltage ◽  
Driving Frequency ◽  
Additional Energy ◽  
Energy Dissipated

Abstract Energy expressions for a piezoelectric actuator coupled to a resonant mechanical load are analyzed for the purpose of determining the energy requirements of controlled structures. The analysis illustrates that the energy dissipated within the linear amplifier is a function of four parameters: the driving frequency, the piezoelectric coupling coefficient, the relative stiffness of the actuator and load, and the amplifier supply voltage. The piezoelectric actuator and the mechanical load are assumed to be lossless to highlight the relationship between energy dissipated within the amplifier and the energy stored in the actuator. For a specific frequency, the minimum energy dissipation within the amplifier is equal to twice the stored electrical energy in the piezoelectric when the amplifier voltage is equal to the driving voltage of the actuator. Additional energy is dissipated within the amplifier when the supply voltage is greater than the driving voltage. In the case when the actuator displacement is constant as a function of frequency, the energy dissipation in the amplifier decreases near the resonance of the coupled electromechanical system and reaches a minimum when the piezoelectric charge due to the applied voltage is equal and opposite to the charge induced by the load. The steady-state amplitude of the charge, and hence the actuator current, is equal to zero at this frequency. The results illustrate that energy dissipation is minimized when the actuator is operated at near the resonance or antiresonance of the coupled electromechanical system.

scholarly journals Design of a Low-Frequency Harmonic Rotary Piezoelectric Actuator

Actuators ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 4
Author(s):  
Kang Liang ◽  
Chong Li ◽  
Yujian Tong ◽  
Jiwen Fang ◽  
Wei Zhong
Keyword(s):  
Piezoelectric Actuator ◽  
Harmonic Wave ◽  
Low Frequency ◽  
Experimental System ◽  
Piezoelectric Actuators ◽  
Driving Voltage ◽  
Driving Frequency ◽  
Output Characteristics ◽  
Driving Signal ◽  
Harmonic Displacement

Piezoelectric actuators usually operate under a high frequency driving signal. Here we report a harmonic rotating piezoelectric actuator by coupling a harmonic wave generator and a friction rotor, in which the actuator can be actuated by a low-frequency sinusoidal signal with positive bias. The harmonic wave is generated by a two-stage magnifying mechanism consisting of a displacement amplifier and a harmonic rod. Applying piezoelectricity theory, the actuator’s output characteristic equations are deduced. What is more, the output characteristics of piezoelectric actuators are tested with the established experimental system. Results show that the generated harmonic displacements can drive the actuator to work normally at a driving voltage of larger than 90 V and the maximum total harmonic displacement of the piezoelectric actuator comes up to 427.6 μm under the driving voltage of 150 V. Meanwhile, the error between the measured and calculated values of the harmonic displacement is less than 7%. Furthermore, the rotational speed of the piezoelectric actuator reaches 5.45 rpm/min at 150 V voltage and 5 Hz driving frequency.

scholarly journals A Novel Rotation-Structure Based Stick-Slip Piezoelectric Actuator with High Consistency in Forward and Reverse Motions

Actuators ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 189
Author(s):  
Jizhou Tang ◽  
Jingsong Wei ◽  
Yuming Wang ◽  
Zhi Xu ◽  
Hu Huang
Keyword(s):  
Piezoelectric Actuator ◽  
Piezoelectric Actuators ◽  
Driving Voltage ◽  
Driving Frequency ◽  
Maximum Displacement ◽  
Stick Slip ◽  
Reverse Motion ◽  
Symmetric Structure ◽  
Deviation Rate ◽  
High Consistency

Under the same driving voltage and frequency, the forward and reverse motion inconsistency of stick-slip piezoelectric actuators would bring difficulty for subsequent control. To solve this problem, a rotation-structure based piezoelectric actuator with completely symmetric structure and two driving feet was initially proposed. By testing its output performances under various driving voltages and frequencies, it was confirmed that, although similar speeds could be achieved for forward and reverse motions, the maximum displacement and backward displacement in each step were still quite different. By analyzing the reasons leading to this difference, this actuator was further improved by using only one driving foot. The experimental results showed that the forward and reverse motion consistency of the improved actuator had been significantly improved. The deviation rate was only 1.6%, corresponding to a travel distance of 118.7 μm, obtained under the driving voltage of 100 V and driving frequency of 10 Hz. The comparison with some previously reported actuators further confirmed the advancement of this improved actuator.

scholarly journals The knit on demand supply chain

2012 ◽  
Vol 12 (3) ◽  
pp. 67-75 ◽  
Author(s):  
Jonas Larsson ◽  
Joel Peterson ◽  
Heikki Mattila
Keyword(s):  
Supply Chain ◽  
Fast Response ◽  
Lead Times ◽  
Customer Demand ◽  
On Demand ◽  
Inventory Turnover ◽  
Flow Through ◽  
The One ◽  
The Cost ◽  
Manufacturing Stage

The knit on demand supply chain As customers’ tastes become more differentiated, so must companies’ offerings evolve. The demand for variety may soon become unmanageable, and several companies are addressing this trend by adopting a system of mass customization. One project, Knit on Demand, has been conducted by the Swedish School of Textiles in close collaboration with a knitting company and a retailer of tailored fashion in Stockholm. Production and sales of customized products pose logistical challenges for the companies involved, including the one-piece flow through almost the entire supply chain and the demand for short lead times in an otherwise slow environment, adding to the cost of manufacturing mass customized garments. Customization has logistical benefits such as minimised inventory; hence, high inventory turnover and the possibility of fast response to meet customer demand. The Knit on Demand concept can be considered as leagile because it comprises both lean and agile components. It is lean in the manufacturing stage upstream and agile downstream to better respond to customer demand on the market.

Modeling Height Profile for Drop-on-Demand Print of UV Curable Ink

2019 ◽  
Author(s):  
Yumeng Wu ◽  
George Chiu
Keyword(s):  
Numerical Models ◽  
Sweet Spot ◽  
Single Drop ◽  
Height Profile ◽  
Uv Curable ◽  
On Demand ◽  
Graphic Model ◽  
Drop On Demand ◽  
Proposed Model ◽  
Better Than

Abstract This paper proposes a height profile model for drop-on-demand printing of UV curable ink. Existing models include superposition of single drops, numerical models, and graphic-based model. They are either too complicated or over simplified. Graphic model intends to find a sweet spot in between, however, accuracy is marginally improved from superposition model while it demands more computation. The proposed model aims to achieve the same as graphic model by introducing volume and area propagation matrices to reflect the localized ink flow from higher location to the lower, while avoiding the detailed physics behind it. This model assumes a constant volume and area propagation of subsequent drop due to height profile difference. It is validated with experiments on single drop, 2-drop and 3-drop line printing. Stability of this model is analyzed.. Using root mean square (RMS) error as benchmark, proposed model achieves 6.6% along the center row and 7.4% overall, better than existing models.

Numerical Study on a Drop-on-Demand Micro Droplet Print Head

2012 ◽  
Vol 217-219 ◽  
pp. 1429-1434
Author(s):  
Cheng Jian Zheng ◽  
Sheng Dong Gao ◽  
Ying Xue Yao
Keyword(s):  
Conceptual Design ◽  
Piezoelectric Actuator ◽  
Numerical Study ◽  
Metal Droplet ◽  
Axisymmetric Model ◽  
Print Head ◽  
On Demand ◽  
Drop On Demand ◽  
Vof Model ◽  
Parametric Studies

A conceptual design of a drop-on-demand(DOD) micro metal droplet print head, which is characterized as the non-heat affection of piezoelectric actuator and a desirable controllability on droplet condition, is devised. With a 2D axisymmetric model and a VOF model, the droplet evolution is simulated for understanding the mechanism within. Parametric studies are followed to investigate relationship between droplet condition and print head parameters for realizing accurate control of droplet condition.

Subjective Time Preference and Willingness to Pay for an Energy-Saving Durable Good

2001 ◽  
Vol 32 (3) ◽  
pp. 133-141 ◽  
Author(s):  
Gerrit Antonides ◽  
Sophia R. Wunderink
Keyword(s):  
Willingness To Pay ◽  
Energy Saving ◽  
Subjective Time ◽  
Durable Good ◽  
Discount Function ◽  
Hyperbolic Discount ◽  
The One ◽  
Two Parameter ◽  
Difference Effect ◽  
Better Than

Summary: Different shapes of individual subjective discount functions were compared using real measures of willingness to accept future monetary outcomes in an experiment. The two-parameter hyperbolic discount function described the data better than three alternative one-parameter discount functions. However, the hyperbolic discount functions did not explain the common difference effect better than the classical discount function. Discount functions were also estimated from survey data of Dutch households who reported their willingness to postpone positive and negative amounts. Future positive amounts were discounted more than future negative amounts and smaller amounts were discounted more than larger amounts. Furthermore, younger people discounted more than older people. Finally, discount functions were used in explaining consumers' willingness to pay for an energy-saving durable good. In this case, the two-parameter discount model could not be estimated and the one-parameter models did not differ significantly in explaining the data.

Exploring the Multidimensional Facets of Authoritarianism: Authoritarian Aggression and Social Dominance Orientation

2008 ◽  
Vol 67 (1) ◽  
pp. 51-60 ◽  
Author(s):  
Stefano Passini
Keyword(s):  
Social Dominance ◽  
Factor Model ◽  
Three Dimensional ◽  
Social Dominance Orientation ◽  
Model Fit ◽  
Regression Analyses ◽  
One Dimensional ◽  
Confirmatory Factor ◽  
The One ◽  
Better Than

The relation between authoritarianism and social dominance orientation was analyzed, with authoritarianism measured using a three-dimensional scale. The implicit multidimensional structure (authoritarian submission, conventionalism, authoritarian aggression) of Altemeyer’s (1981, 1988) conceptualization of authoritarianism is inconsistent with its one-dimensional methodological operationalization. The dimensionality of authoritarianism was investigated using confirmatory factor analysis in a sample of 713 university students. As hypothesized, the three-factor model fit the data significantly better than the one-factor model. Regression analyses revealed that only authoritarian aggression was related to social dominance orientation. That is, only intolerance of deviance was related to high social dominance, whereas submissiveness was not.

Designing Women

2018 ◽  
Author(s):  
J. E. Smyth
Keyword(s):  
Working Women ◽  
Costume Design ◽  
Creative Force ◽  
Women's Fashion ◽  
The One ◽  
Studio Era ◽  
Average Woman ◽  
Better Than

During the early 1940s, journalists observed that after years of men controlling women’s fashion, Hollywood had become “a fashion center in which women designers are getting to be a big power.” In a town where “the working girl is queen,” it was women who really knew how to dress working women. Edith Head’s name dominates Hollywood costume design. Though a relatively poor sketch artist who refused to sew in public, Head understood what the average woman wanted to wear and knew better than anyone how to craft her image as the-one-and-only Edith Head. However, she was one of many women who designed Hollywood glamour in the studio era. This chapter juxtaposes Head’s career with that of a younger, fiercely independent designer who would quickly upstage Head as a creative force. In many senses, Dorothy Jeakins’s postwar career ascent indicated the waning of the Hollywood system and the powerful relationship between female designers, stars, and fans.

Sign in / Sign up

Export Citation Format

Share Document