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The purpose of this paper is to introduce the structure design process of the cantilever spindle with limited installation space and wishing to increase its critical speed.

In this paper, the finite element method was used to analyze the influence of the supporting stiffness and the structure of the spindle on the critical speed, and then the structure of the spindle was designed; moreover, the experiment was accomplished and the experiment results show that the spindle can work stably.

Through analyzing the influence of the supporting stiffness and the structure of the spindle on the critical speed, the following conclusions could be obtained: the shape of the first-mode is the bend vibration of the cantilever of the spindle; the first-order critical speed of the spindle gradually decreases with the diameter and length of the cantilever increasing; the first-order critical speed of the spindle increases with the depth and diameter of the blind hole increasing; and the experiment was accomplished and the experiment results show that the spindle can work stably.

In this paper, the finite element method was used to design the spindle of the testing machine, and satisfactory results were obtained. It can provide a theoretical reference for the design of a similar spindle.

The severe friction and wear of the spindle in a cotton picker often occur in a picking cotton, which affects the spindle lifetime and its efficiency of picking cottons. This paper aims to investigate the effect of an electroless nick coating on the spindle performances to avoid its abnormal phenomena.

First, it is coated on the surface of the test specimen with the material same as that of the spindle. Then, the friction coefficient and wear for the coating are measured under oil lubrication to evaluate its effect in improving the tribological performances for the spindle.

The stabilized friction coefficient of the electroless nick coating decreases with increasing reciprocating frequency of specimen and increasing applied load. There exists a critical coating thickness yielding the smallest friction coefficient. Moreover, this coating has a property of the smaller friction coefficient in comparison with a hard chromium coating.

The research about the electroless nick effect on the spindle’s tribological performances is not found yet to date. To avoid severe friction and wear of the spindle, this paper investigated how the reciprocating frequency of specimen, applied load and coating thickness affect the spindle’s tribological performances. The associated conclusions can provide a reference to enhance the spindle lifetime and its transmission efficiency.

This paper aims to study the influence degree of three factors affecting the vibration amplitude of aerostatic spindle and optimizes each factor.

The vibration amplitude of the spindle is characterized according to internal structure and operating characteristics of aerostatic spindle. The radial and axial vibration models of aerostatic spindle were established by the spring-damper system. The influence degree of main influencing factors on the spindle vibration amplitude was investigated through correlation analysis.

The results indicate that the crucial factor is aerostatic spindle speed and experiments validated that increasing spindle speed can enhance spindle stability. The influence of three factors on radial vibration is greater than that on axial vibration. Finally, the values of optimal working parameters were obtained by genetic algorithm.

The method in this article can effectively predict aerostatic spindle vibration amplitude and perfect the stability of aerostatic spindle.

The purpose of this paper is to investigate the effect of fluid–structure interaction in micro-scale on the performance of the hydrostatic spindle and improve the analysis precision of the dynamic performance of hydrostatic spindle.

Dynamic analysis of hydrostatic spindle before and after fluid–structure interaction is carried out according to stiffness and damping performance of the bearing, which demonstrates that the natural frequency and peak response of the spindle are increased in the micro-scale.

It is concluded from the simulation and experimental results that there is micro-scale effect in the actual operation of the spindle system and slippage exists in the oil film flow. The error between the modal detection result and the theoretical value is within 10 per cent, which also verifies the correctness of the above conclusions.

This paper analyzes the changes of the bearing performance parameters at macro- and micro-scale, which present the influence of the static and dynamic performance of the spindle in the micro-scale.

In high-speed processing, the influence on the machining accuracy of a machine tool is greatly caused by the thermal deformation of the motorized spindle; a further study on the thermal characteristics of the spindle is given in this paper. This study aims to reduce the thermal error and improve the performance of the machine tool by discussing the relationships between the temperature distributions and rotating accuracy caused by the thermal deformations of the spindle.

The paper opted for a method combining the theoretical analysis and the experimental study to study the thermal stability of the high-speed motorized spindle. First of all, a finite element model of the spindle was built with ANSYS, whereby temperature distributions and the thermal deformations were successively obtained at different speeds. And then, both the temperature field and the rotating accuracy of the motorized spindle were measured simultaneously by the thermal stability experiment. Finally, the experimental and theoretical results were compared and validated.

The thermal stability of the motorized spindle was studied in this paper, and some findings from the study were as follows: the spindle’s rotating accuracy maintained good in X direction but bad in Y and Z directions in terms of the deformations; the higher front-end temperature of the spindle which can significantly affect the rotating accuracy is needed to be controlled mainly; the recovery speed of the spindle deformation lagged behind the temperature’s fallback speed; the vibration graph about radial rotating sensitivity synthesized by X1 and X2 presented a trifoliate shape.

Based on a built test-bed which can synchronously measure the motorized spindle’s temperature distribution and rotating accuracy with five-point method, the coupling effects of the thermal deformation and temperature are embodied, and not only the vibration graph but also the thermal tilt angles can be gained. Therefore, considering the influence of the thermal deformation on the heat generated by the bearings, the paper fulfilled a study by which it was obtained that the front-end temperature of the spindle, which was higher and could significantly affect the rotating accuracy, needed to be controlled mainly.

Multitasking machining (MTM) systems have become increasingly sophisticated and expensive capital equipment. The lack of practical guidelines for selection of these machines can lead to significant undesirable machine attributes, application mismatch, and longer return on investment. The purpose of this paper is to provide an insight to numerous features and configurations of MTM systems and to present several application‐based selection guidelines.

A taxonomy of MTM systems is developed based on the number of axes of motions, tooling and spindle systems. Practical guidelines for general and advance features are presented with special regard to multi‐axis and multi‐spindle features.

MTM systems are capable of meeting several production goals such as cycle time reduction, minimizing non‐value added times and concurrent processing of multiple parts. However, they possess inherent programming challenges due to their complex configuration and simultaneous machining functions.

The diversity of system configurations demand a decision support system, such as a rule‐based expert system to capture the many variations of MTM systems.

This paper should be useful to decision makers in industry or academia who are involved in selection of MTM systems.

Biofilms are bacterial communities embedded in exopolysaccharide, enhancing the difficulty of detaching bacterial cells from surfaces. Due to structural properties, it is difficult to detach biofilms. Many removal methods have been developed, but there are still some limitations such as sample size and reproducibility. “Spindle” was developed, producing a higher quality suspension which can be used for further study. The paper aims to discuss these issues.

The authors compared the enumeration of biofilm-forming cells detached from the spindle and stomacher in various surfaces. First, the authors chose stainless steel and polyvinyl chloride to attach biofilms and to be subjected to stomacher and spindle for up to 2 min. Also, the authors evaluated the efficiency of detachment from vegetable surfaces.

In a comparative experiment of abiotic surfaces, the spindle showed identical effectiveness for detaching biofilm-forming cells compared to the stomacher, recovering the population by 8-log for Escherichia coli O157:H7, Salmonella Typhimurium and Listeria monocytogenes. The spindle also showed no significant difference from the stomacher in the number of recovered cells which is 4-log from vegetable surfaces. However, turbidity after spinach was subjected to spindle was 4.37 NTU, while it was 99 NTU for stomacher, which was in accord with visual result about clearance.

This study demonstrated that the spindle is a useful to separate biofilms from surfaces without destructing structure, and thus it can be used for analysis in food laboratories as well as utilized for vegetable washing step in the food industry.

Drawing Frames, Combers and Roving Frames. Drawing Frames (Fig. 3) are simple in construction, yet they must be in good mechanical condition and carefully maintained in order to produce uniform, strong, high‐quality yarn. Roll bearings present an important lubrication problem. The weighting of the top rolls is distributed both to top‐roll and bottom‐roll bearings. Microscopic tenacious persistent films of lubricating oil must prevent metallic contact with the roll necks inorder to minimise friction, wear and power consumption. This must be accomplished with sparing application of correct oil if throw and spotting are to be prevented. It is the practice in some mills to use a fluid grease in order to minimise the possibility of oil creeping from the bearings and staining the slivers.

For using wireless sensors to monitor spindle units without opening the spindle shell to replace the battery, harvesting the waste heat from spindle units of machine tools for thermoelectric generation to drive wireless sensors is studied in this paper. The paper aims to discuss these issues.

In this paper, the thermal network method and the analogies between electrical and thermal domains are used in the simulation of power output performance of thermoelectric generation on a rotating spindle. After that, experiments are done to obtain the real power output performance of the generation and evaluate the feasibility to drive wireless sensors.

The paper provides that the output voltage of the thermoelectric generations was nearly linear with the rotating speed of the spindle, the output voltage was sensitive to the fixed position of the generations, and the thermoelectric system could drive the wireless sensor well most of the time during continuous operation of the spindle.

It is found that the thermoelectric generation could not provide enough power in the early start-up stage of the spindle rotation, so a high-efficiency power manage system, which will be studied in the future research, is needed to handle this problem.

The paper includes implications for the development of self-powered wireless sensors in the spindle unit for machine tool monitoring.

The paper develops a model of the power output performance of thermoelectric generation on a rotating spindle and tests the feasibility to drive wireless sensors with this power.

The spindle behavior of machines and systems depends largely on the choice and design quality of the mechanical components used for the displacement between different parts. As far as very high technology is concerned, air bearings are suitable, for instance, for machining a telescope mirror or for systems used in medical applications that require a micro and nanometric resolution in displacement. Therefore, air bearings play a crucial role in ensuring spindle stability in machines and systems. The static and dynamic behavior of air spindles is dependent on several parameters, such as external load, dimensions, supply pressure, manufacturing capability and fluid properties.

This paper presents a methodology for the calculation and analysis of the stability and reliability of machine and system spindles supported by air hemispherical bearings. The static and dynamic characteristics of air spindles are calculated using the finite element method (FEM). The stochastic Response Surface Method (SRSM) is used for the approximation of the performance function, and the reliability is assessed by Monte Carlo Simulation (MCS) and the First Order Reliability Method (FORM).

The static and dynamic characteristics of air spindles are calculated using the finite element method (FEM). Stochastic Response Surface Method (SRSM) is used for the approximation of the performance function, and the reliability is assessed by Monte Carlo Simulation (MCS) and First Order Reliability Method (FORM).

The article presents an original approach for the behavior analysis of machines and systems spindles supported by hemispherical fluid bearings. The methodology based on the finite element method and the principle of structural reliability, allows studying the influence of physical and geometrical parameters on the static and dynamic characteristics and the failure probability of a spindle. Thus, the optimum behavior of a spindle can be predicted for different configurations of a bearing design taking into account the reliability evaluation.