Conical Spring Research Articles

Vertically polarizing undulator with the dynamic compensation of magnetic forces for the next generation of light sources.

A short prototype (847-mm-long) of an Insertion Device (ID) with the dynamic compensation of ID magnetic forces has been designed, built, and tested at the Advanced Photon Source (APS) of the Argonne National Laboratory. The ID magnetic forces were compensated by the set of conical springs placed along the ID strongback. Well-controlled exponential characteristics of conical springs permitted a very close fit to the ID magnetic forces. Several effects related to the imperfections of actual springs, their mounting and tuning, and how these factors affect the prototype performance has been studied. Finally, series of tests to determine the accuracy and reproducibility of the ID magnetic gap settings have been carried out. Based on the magnetic measurements of the ID Beff, it has been demonstrated that the magnetic gaps within an operating range were controlled accurately and reproducibly within ±1 μm. Successful tests of this ID prototype led to the design of a 3-m long device based on the same concept. The 3-m long prototype is currently under construction. It represents R&D efforts by the APS toward APS Upgrade Project goals as well as the future generation of IDs for the Linac Coherent Light Source (LCLS).

Design of Shock-Absorbing System for Disaster Rescue Robot

Disaster Rescue Robot is a small caterpillar robot used for carrying first aid articles, reasonable shock-absorbing system is an indispensable part to reduce the rush of the ground because it has to plummet from a certain level to the ground when it works. We use the method of modular design in this article and design the landing gear based on the performance of conical spring in order to absorb some of the forces during a fall. Then the three-dimensional modeling software is used to establish the parametric model of the robot shock-absorbing system to provide an effective way for the design of the Disaster Rescue Robot.

The Research on Working Performance of Annular Valve Spring Based on Solidworks

According to the problem of cylindrical helical compression springs deformation and fracture in the process of using. come up with a Solution that use conical helical spring instead of it, validate the improvement measure with relevant simulation and test analysis, draw a conclusion that the working performance of conical helical spring is better than the cylinder, this paper has some guiding effect on the selection of Annular valve spring.

Analytical and Experimental Study of Conical Telescoping Springs With Nonconstant Pitch

Most research papers that exploit conical springs focus only on conical springs with a constant pitch. In order to increase the range of possibilities for designers, this paper proposes a study of conical springs with other types of spirals projected on the conical shape. This study is related to three other types of conical springs: with a constant helix angle, with a constant stress at solid and with a fully linear load-length relation. For each spring, we give the equation of the spiral, the formula of the initial stiffness, and formulae to calculate the nonlinear part of the load-length relation for fully telescoping springs. We also report an experimental study performed to analyze the accuracy of the proposed study based on springs made by fused deposition modeling.

Design of Moving System for Pico-Satellite Deployer

Pico-satellite’s potential use is increasingly gaining nation’s recognition. Because of its small volume and light weight, it is necessary to develop the special deployer. The key technologies of Zhejiang University Pico-Satellite Deployer (ZDPSD) are, cutter unlocking the door, conical spring driving the pico-satellite, oriented rail restricting the direction and locking shaft fixing the door. In September 2010, the two pico-satellites were launched and deployed successfully at the predetermined orbit. The paper includes designing and analyzing of the moving system, mode analyzing of the deployer and the experiments on ground and in-orbit. The key process of the development is summarized, which can be regarded as reference for the further developing.

Heat transfer and exergy loss in conical spring turbulators

It would be misleading to consider only the construction costs of heat exchangers in their design because high service costs during their service life may also greatly increase total costs. Therefore energy saving aspects are very important in the design, construction and operation of the heat exchangers. For this reason, various active or passive methods have been sought to save energy by increasing the heat transfer coefficients in the cold and warm fluid sides in the heat exchangers. Conical spring turbulators (CST) are devised in this study. Performances of heat transfer and pressure drop in a pipe with the CST are experimentally examined for the CSTs’ angle (θ) of 30°, 45° and 60° in Reynolds number (Re) range of 10,000–34,000. Heat transfer, pressure loss and exergy analysis were made for the conditions with and without turbulators and compared to each other. Some empirical correlations expressing the results were also derived and discussed.

Function Simulation Analysis for Conical Spring of DANA Axis-Fixed Transmission

The conical spring is one critical part of DANA MHR-3200 series Transmission, its structure is compact and it has good stability and used for bearing larger load and vibration attenuation. Using SolidWorks Simulation to conduct simulation analysis for the stiffness and modality of conical spring, acquire the deformation law of spring under service load, the stiffness curve with nonlinear characteristics, the first four orders natural frequencies and its modal shape, which will lay a foundation for the RE design of conical spring and provide basis for its reconfiguration and repair after lose efficacy.

Dynamic behavior of valve system in linear compressor based on fluid-structure interaction

In refrigerator designs, the linear compressor is preferable to the recipro-type compressor, due to its higher energy efficiency. The linear compressor’s valve system, however, causes significant noise, not only in the steady state but also in the transient state. To accurately predict the behavior of the suction and discharge valve system in both states, the interaction between the fluid flowing through the valves and the structural deformation of the valves needs to be understood. In the present study, the steady-state behaviors of the valve system were numerically analyzed using ADINA software, which takes fluid-structure interaction (FSI) into account. This computational analysis thereafter was experimentally validated. The effects of a pre-load of the conical compression spring on the dynamic characteristics of the valve system also were analyzed.

가변길이 엔드팁을 갖는 원추형 스프링을 이용한 도약로봇의 이동성 향상

Mobility is one of the most important features for a guard robot since it should be operated in rough places. A wheel-based mobile robot capable of jumping is an appropriate structure for a guard robot because it can easily satisfy the requirements for small guard robots. The jumping robot can reach a higher place more rapidly than other locomotion methods. This research proposes a small robot equipped with the jumping mechanism based on the conical spring with the variable length endtip. The variable length endtip enables the independent control of the jump force and jump angle which are related to the jump height and jump distance, respectively. Various experiments demonstrated that the proposed jumping mechanism can provide the independent control of jump force and jump angle, and improve the mobility of a small robot to overcome an obstacle. Furthermore, a combination of the jumping mechanism and the PSD sensor to measure the distance to the step enable the jumping robot to autonomously climb stairs.

Optimal design of conical springs

Mechanical systems often use springs to store energy though their axial length must sometimes be significantly reduced. This leads to the use of conical springs as they are able to telescope. Desig...

Optimal design of conical springs

Mechanical systems often use springs to store energy though their axial length must sometimes be significantly reduced. This leads to the use of conical springs as they are able to telescope. Designers of mechanical systems can call on a large number of tools to assist them though most of these are merely validation tools requiring concomitant trial and error strategies. Optimization strategies can be applied to provide synthesis assistance tools for which the designer simply specifies his requirement. Thus the tool directly indicates the spring best suited to standards and requirements. Recent advances in the study of constant pitch conical springs have provided analytical expressions of their behavior even in the non-linear phase. Considering this, we have used optimization strategies to provide a synthesis tool for conical spring design. An example of application is presented. The tool introduced here is thus a synthesis assistance tool that can be of considerable interest for designers who require a conical spring in their design.

Low driving energy engine valve mechanism using permanent-electromagnet and conical spring

Low driving energy engine valve mechanism using permanent-electromagnet and conical spring

Low Torque Engine Valve System Using Conical Coil Spring and Electromagnetic Actuator

In this research, a new type valve system using a conical coil spring and an electromagnetic actuator was developed. This system uses a conical coil spring whose spring constant is low, and therefore, the valve system has a low torque in a low-speed rotation mode. As a result, the energy loss in a low-speed rotation is decreased. However, the jump and bounce phenomena would happen in the high-speed rotation mode. The phenomena are suppressed by using an electromagnetic actuator consisting of two permanent magnets and electromagnet. The electromagnetic actuator strengthens the restoration force of the spring by the repulsive force, and controls the jump and bounce phenomena. It was confirmed that the use of a conical coil spring lessened the load torque in this experiment and that the jump and bounce phenomena were suppressed by using the present electromagnetic actuator.

Evaluation of Loosening Resistance Performance of Conical Spring Washer by Three-dimensional Finite Element Analysis

The conical spring washer (CSW) has been considered to prevent the loosening of a bolted joint and has thus been widely employed. However, experimental results obtained in studies focusing on loosening due to transverse loading conducted by Yamamoto et al. and Sakai have shown that a CSW did not prevent loosening in any context. In the present paper, we performed three-dimensional finite element analyses of an M10 bolted joint using a CSW subjected to transverse loading and investigated its loosening resistance performance. Two kinds of axial force were applied: one was low axial force (10kN) under which a CSW is not fully compressed, and the other was high axial force (20kN) under which a CSW is fully compressed. In the case of high axial force, the CSW showed no vivid effect on preventing loosening. On the other hand, in the case of low axial force, the CSW showed two opposite effects. The negative effect was an increase in the loosening rotation angle, while the positive one was the prevention of a decrease in axial force. When complete bearing-surface slip occurs, a CSW can prevent loosening because the positive effect is larger than the negative. However, when small bearing-surface slip occurs, a CSW cannot prevent loosening because the negative effect cancels the positive one. It is supposed that the small stuck region as well as the small equivalent diameter of friction torque leads to large loosening rotation.

Experimental chaos in nonlinear vibration isolation system

The chaotic vibration isolation method was studied thoroughly from an experimental perspective. The nonlinear load-deflection characteristic of the conical coil spring used in the experiment was surveyed. Chaos and subharmonic responses including period-2 and period-6 motions were observed. The line spectrum reduction and the drop of the acceleration vibration level in chaotic state and that in non-chaotic state were compared, respectively. It was concluded from the experiment that the nonlinear vibration isolation system in chaotic state has strong ability in line spectrum reduction.

An Engine Mount Stacked with Auto-Tuning Anti-resonance Dynamic Absorber Consisting of Conical Springs and Vibration Isolation Control Method

An engine mount is developed which is consisting of a fluid filled rubber mount stacked with a variable spring constant absorber. In engine mounts, the transmissibility due to mass vibrations should be small, and high frequency vibration causing noise should be isolated. In the mount developed by the authors, the high frequency vibrations are isolated with a fluid filled rubber mount. It is difficult to suppress both mass vibrations and its transmissibility to the base simultaneously. For suppressing both, the authors applied an anti-resonance control system. In order to achieve the anti-resonance condition, a new type tunable absorber using conical helical spring is developed, and its control method is presented. Using our mount, both the mass vibration and transmissibility can be suppressed, and the amplitude ratio and the transmissibility can be controlled to be less than one which will be difficult to be achieved in the previous mounts. The present mount has other advantages on its compact size, small control energy and simple control system.

702 三次元有限要素法解析による皿ばね座金のゆるみ止め性能評価(GS.S 構造解析)

702 三次元有限要素法解析による皿ばね座金のゆるみ止め性能評価(GS.S 構造解析)

4.3.3 Applying Systems Modeling Language to A Simple Hardware System

AbstractThis paper used the Systems Modeling Language (SysML) to explore its applicability and effectiveness to a simple hardware system. The system and design requirements derived from the customer requirements were modeled in the requirements hierarchy diagram. The spring load equation with all the variables and constant were defined in the parametric constraint definition diagram. Parametric constraint on a block diagram was then used to design a conical helical spring. A link between design and requirements was demonstrated in the model. State machine diagrams depicted the finite state‐transition on how a person emptied the mousetrap and how a mouse entered the trap. These diagrams were linked to verification requirements for system verification. SysML is shown to be an effective modeling language for hardware systems. The applicability of SysML to a combined hardware and software system has still to be demonstrated and proven.

Improvement in Sensitivity of Thin Plate Sensor for Bolt Loosening on Early Stage

Bolted joints sometimes suffer bolt loosening and may sometimes induce accidents. Therefore. bolt loosening detection technologies are essential for many machines and structures having bolted joints. Authors have proposed a new bolt loosening detection sensor using a natural frequency change of a thin plate and validity of the sensor is shown by experimental results. However, it is difficult to detect the bolt loosening on early stage because the sensor is not so sensitive in high axial tension condition. In this paper. the mechanism of natural frequency change of the sensor induced by axial tension change of bolt is investigated with numerical and experimental results and two sensitivity improvement methods, using conical spring washers and size change of the sensor are examined. The results show that size change of the sensor is not effective for improvement of the sensitivity on early stage of bolt loosening and that conical spring washers change the contact area on each sensor surface and can improve the sensitivity on early stage of bolt loosening.

Analytical Behavior Law for a Constant Pitch Conical Compression Spring

Cylindrical compression spring behavior has been described in the literature using an efficient analytical model. Conical compression spring behavior has a linear phase but can also have a nonlinear phase. The rate of the linear phase can easily be calculated but no analytical model exists to describe the nonlinear phase precisely. This nonlinear phase can only be determined by a discretizing algorithm. The present paper presents analytical continuous expressions of length as a function of load and load as a function of length for a constant pitch conical compression spring in the nonlinear phase. Whal’s basic cylindrical compression assumptions are adopted for these new models (Wahl, A. M., 1963, Mechanical Springs, Mc Graw-Hill, New York). The method leading to the analytical expression involves separating free and solid/ground coils, and integrating elementary deflections along the whole spring. The inverse process to obtain the spring load from its length is assimilated to solve a fourth order polynomial. Two analytical models are obtained. One to determine the length versus load curve and the other for the load versus length curve. Validation of the new conical spring models in comparison with experimental data is performed. The behavior law of a conical compression spring can now be analytically determined. This kind of formula is useful for designers who seek to avoid using tedious algorithms. Analytical models can mainly be useful in developing interactive assistance tools for conical spring design, especially where optimization methods are used.