US 12,253,134 B2
Coil spring device
Taisuke Suwa, Yokohama (JP); Yuichi Shibata, Yokohama (JP); Ippei Kokubun, Yokohama (JP); and Tomoya Sugitani, Yokohama (JP)
Assigned to NHK SPRING CO., LTD., Kanagawa (JP)
Filed by NHK SPRING Co., Ltd., Yokohama (JP)
Filed on Sep. 28, 2022, as Appl. No. 17/954,907.
Application 17/954,907 is a continuation of application No. PCT/JP2021/012287, filed on Mar. 24, 2021.
Claims priority of application No. 2020-064642 (JP), filed on Mar. 31, 2020.
Prior Publication US 2023/0016117 A1, Jan. 19, 2023
Int. Cl. F16F 3/12 (2006.01)
CPC F16F 3/12 (2013.01) [F16F 2226/042 (2013.01); F16F 2230/0005 (2013.01)] 2 Claims
OG exemplary drawing
 
1. A coil spring device comprising:
a main body spring in which a wire rod extends vertically in a spiral shape around a coil axis; and
an insulator which supports a lower end portion of the main body spring from below the main body spring,
wherein the insulator is provided with a support groove which extends around the coil axis and into which the lower end portion of the main body spring is fitted,
wherein the lower end portion of the main body spring adheres to an inner surface of the support groove,
wherein the inner surface of the support groove is provided with a plurality of spacer protrusions which support an outer peripheral surface of the wire rod,
wherein the support groove extends in an angle range of 180° or more and 360° or less around the coil axis, and
wherein a ratio of a volume of the spacer protrusions occupying a gap between the inner surface of the support groove and the outer peripheral surface of the wire rod at a center portion in the gap in a circumferential direction around the coil axis is larger than that at the other portions in the gap in the circumferential direction.