Acoustic insulation device for mounting in a tubular part, particularly in a bodywork part of a motor vehicle

An acoustic insulation device for mounting in a tubular part of the bodywork of an automobile comprising a partitioning insert with around it a thermally expandable foam forming cord held in place by retaining means and including means of favorizing the expansion of the cord in the direction of the inner periphery of the tubular part. An acoustic insulation device for mounting in a tubular part of the bodywork of an automobile comprising a partitioning insert with around it a thermally expandable foam forming cord held in place by retaining means and including means of favorizing the expansion of the cord in the direction of the inner periphery of the tubular part. The device is as shown in Figure 2. The cord is produced by extrusion in a straight sided form without any special shaping. The retaining means, which are molded with the partitioning insert also act to ensure correct expansion of the cord. In an alternate form of the device it consists of two plates fixed to one another and separated by a lateral wall which forms a brace and delimits a peripheral depression suitable for receiving the cord. The wall is provided with pressure relief vents to prevent distortion of the insert during expansion of the cord. An Independent claim is included for a tubular part of the bodywork of an automobile which comprises a claimed device.