Product category:
Fasteners, threaded and non-threaded
News Release from: Rencol Tolerance Rings | Subject: Crown Ring
Edited by the Engineeringtalk Editorial
Team on 12 April 2005
Radial spring fastener answers
automotive demands
The Crown Ring is a novel radial spring fastener with several sprung fingers which when deflected give a required load.
Electric motors are being used to drive an increasing number of devices in motor vehicles One such application is the use of electric motors within the throttle body to control the butterfly valve, commonly known as ETC, or electronic throttle control
This article was originally published on Engineeringtalk on 18 Aug 2008 at 8.00am (UK)
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In using electric motors for this application engineers are confronted with a number of issues including: operating temperatures of up to 150C; tolerances of motor and housing up to 0.8mm in total; vibration of the engine/movement of the motor; and failure of the electrical connections due to vibration.
In many applications the motor is only fixed at the front and the engine vibration can lead to fatigue failure - or fretting corrosion - of the electrical terminals, as the rear of the motor is not supported.
The throttle body is commonly made from aluminium and the motor has a steel case.
The wide tolerances on the motor housing and differences in the thermal expansion of the materials have meant that a simple cost-effective mounting solution for the rear of the motor has not been previously available.
Rencol Tolerance Rings, manufacturer of innovative radial spring fastening solutions, has developed a unique way of coping with these variables.
The "Crown Ring" is a radial spring fastener with several sprung fingers which when deflected give a required load.
The height and number of sprung fingers is altered in each design to cope with system tolerances, thermal expansion and support of the motor weight, while maintaining low assembly forces.
The Crown Ring is the latest in a series of cost-effective innovations that Rencol Tolerance Rings has to offer the automotive engineer. Request a free brochure from Rencol Tolerance Rings ...
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