Nomograms for the design of light weight hollow helical springs

2016 ◽  
Vol 231 (23) ◽  
pp. 4388-4394 ◽  
Author(s):  
William J Bagaria ◽  
Ron Doerfler ◽  
Leif Roschier
Keyword(s):  
Maximum Shear Stress ◽  
Extreme Temperature ◽  
Helical Spring ◽  
Transportation Fuel ◽  
Suspension Spring ◽  
Helical Springs ◽  
Fuel Savings ◽  
Suspension Systems ◽  
Round Wire ◽  
Trial And Error Method

The helical spring is a widely used element in suspension systems. Traditionally, the springs have been wound from solid round wire. Significant weight savings can be achieved by fabricating helical springs from hollow tubing. For suspension systems, weight savings result in significant transportation fuel savings. This paper uses previously published equations to calculate the maximum shear stress and deflection of the hollow helical spring. Since the equations are complex, solving them on a computer or spreadsheet would require a trial-and-error method. As a design aid to avoid this problem, this paper gives nomograms for the design of lightweight hollow helical springs. The nomograms are graphical solutions to the maximum stress and deflection equations. Example suspension spring designs show that significant weight savings (of the order of 50% or more) can be achieved using hollow springs. Hollow springs could also be used in extreme temperature situations. Heating or cooling fluids can be circulated through the hollow spring.

Surging in Helical Valve Springs

1933 ◽  
Vol 37 (271) ◽  
pp. 641-654
Author(s):  
J. Dick
Keyword(s):  
Internal Combustion Engine ◽  
High Speed ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Helical Spring ◽  
Dynamic Effects ◽  
Helical Springs ◽  
Air Resistance ◽  
Speed Of Propagation

The high-speed internal combustion engine presents many problems arising from dynamic effects. Amongst these is the phenomenon known as “ surging ” in the helical springs used for the operation of the valves.If a helical spring is held at both ends, any disturbance in the spring passes up and down as a wave, being reflected at each end in turn. This to and fro movement continues until it is damped out by friction and air resistance. With most springs the speed of propagation of the disturbance is considerable and only a confused flutter of the coils is apparent to an observer. A disturbance of this type is caused by any movement of the end of the spring. The more abrupt the movement of the end, the more pronounced will the disturbance be. An instance of the type of movement producing a pronounced surge is that due to impact between the tappet and the valve when the valve commences to open.

scholarly journals Localized electrodeposition micro additive manufacturing of pure copper microstructures

2021 ◽  
Author(s):  
Wanfei Ren ◽  
Jinkai Xu ◽  
Zhongxu Lian ◽  
Xiaoqing Sun ◽  
Zheming Xu ◽  
...  
Keyword(s):  
Additive Manufacturing ◽  
Electrochemical Deposition ◽  
Closed Loop ◽  
Pure Copper ◽  
Closed Loop Control ◽  
Helical Spring ◽  
Loop Control ◽  
Helical Springs ◽  
Atomic Force ◽  
Microscopic Morphology

Abstract The fabrication of pure copper microstructures with submicron resolution has found a host of applications such as 5G communications and highly sensitive detection. The tiny and complex features of these structures can enhance device performance during high-frequency operation. However, the easy manufacturing of microstructures is still a challenge. In this paper, we present localized electrochemical deposition micro additive manufacturing (LECD-μAM), combining localized electrochemical deposition (LECD) and closed-loop control of atomic force servo technology, which can print helical springs and hollow tubes very effectively. We further demonstrate an overall model based on pulsed microfluidics from a hollow cantilever LECD process and the closed-loop control of an atomic force servo. The printing state of the micro-helical springs could be assessed by simultaneously detecting the Z-axis displacement and the deflection of the atomic force probe (AFP) cantilever. The results showed that it took 361 s to print a helical spring with a wire length of 320.11 μm at a deposition rate of 0.887 μm/s, which could be changed on the fly by simply tuning the extrusion pressure and the applied voltage. Moreover, the in situ nanoindenter was used to measure the compressive mechanical properties of the helical spring. The shear modulus of the helical spring material was about 60.8 GPa, much higher than that of bulk copper (~44.2 GPa). Additionally, the microscopic morphology and chemical composition of the spring were characterized. These results delineated a new way of fabricating terahertz transmitter components and micro-helical antennas with LECD-μAM technology.

Maximum Performance of Helical Springs

1947 ◽  
Vol 14 (1) ◽  
pp. A53-A54
Author(s):  
E. I. Shobert
Keyword(s):  
Stainless Steel ◽  
Modulus Of Elasticity ◽  
Maximum Stress ◽  
Helical Spring ◽  
Maximum Performance ◽  
Material Constants ◽  
Helical Springs ◽  
Beryllium Copper ◽  
A Value ◽  
The Way

Abstract A method has been derived for determining the way the spring material influences the volume of space required for a particular application for a helical spring. It is found that this volume is proportional to the material constants of the spring in the following manner VαG7S115 where G is the torsional modulus of elasticity and S is the limit of maximum stress. Using a multiplier to give this factor a value of 1.00 for music wire, it is found that the value for stainless steel is 1.06, beryllium copper 1.34, and phosphor bronze 2.66, for the springs on the brushes of small motors where springs must operate at temperatures up to 100 C. Different fields of application requiring different limits of maximum stress will change these values but the method still remains the same.

Potentialities of Active Suspensions for the Improvement of Handling Performances

2010 ◽  
Author(s):  
Francesco Braghin ◽  
Alessandro Prada ◽  
Edoardo Sabbioni
Keyword(s):  
Load Transfer ◽  
Ride Comfort ◽  
Control Strategies ◽  
Active Suspension ◽  
Suspension Spring ◽  
Suspension Systems ◽  
Active Suspension Systems ◽  
In Series ◽  
High Bandwidth ◽  
Damper Control

Active and semi-active suspension systems are widely diffused into the automotive industry and several control strategies have been proposed in the literature both concerning ride comfort and handling. The capability of several suspension active control systems in enhancing the vehicle handling performances are compared in this paper. In particular, a low-bandwidth active suspension (actuator in series with the suspension spring), an active antiroll bar, an active camber suspension and a semi-active high-bandwidth suspension (closed loop damper control) are considered. The benchmark is represented by an ideal vehicle which does not present any load transfer and has no yaw moment of inertia. The possibility of combining more than one active/semi-active suspension system is also discussed.

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