Nhk Spring Co., Ltd.

Masahiro Umezawa

Tomotake Kato

Ken Takahashi

Toshiaki Sato

Michihiko Ayada

Akihiko Nishikawa

Mitsuhiro Sugiyama

Yoshio Kobayashi

Kenji Yamamotoya

Hideto Enomoto

Daisuke Takeda

Taichi Inage

Suguru Kajigaya

Toshio Hamano

Masanao Ueda

A method for manufacturing a hollow spring member having a hollow steel spring rod having terminal sealed portions at both ends thereof. Each terminal sealed portion has a rotationally symmetric shape in which an axis passing through a center of the spring rod is an axis of symmetry. Each terminal sealed portion has an end wall portion including an end face; an arc-shaped smoothly curved surface between an outer peripheral surface of the spring rod and the end face, and a hermetically closed distal-end-center closure portion on the axis passing through the center of the spring rod. The method includes forming each of the end portions of the spring rod by forming a chamfered portion on an inner or outer peripheral side of the end portion of a hollow wire, the end portion having an opening portion at a distal end, heating the end portion of the hollow wire having the chamfered portion, and spinning the heated end portion to be gathered toward the axis from the outer peripheral side by a jig. The end wall portion, which includes the distal-end-center closure portion, is formed by the distal end of the end portion being joined together on the axis.

Method of manufacturing a hollow spring member

A method of manufacturing a hollow coil spring which is made of a hollow wire in which a terminal sealed portion is formed on an end portion of the wire. The terminal sealed portion has a rotationally symmetric shape in which an axis passing through the center of the wire is the symmetric axis. The hollow coil spring includes an end wall portion, and an end face arc-shaped curved surface. The end wall portion includes an end face perpendicular to the axis. A distal-end-center closure portion is formed on the axis at the center of the end wall portion. A spring seat includes a base member and a sheet member. An end turn portion of the hollow coil spring is in contact with the sheet member. The end face of the end turn portion is opposed to a stopper wall of the spring seat.

Hollow coil spring and suspension device for vehicle

A hollow coil spring is made of a hollow wire in which a terminal sealed portion is formed on an end portion of the wire. The terminal sealed portion has a rotationally symmetric shape in which an axis passing through the center of the wire is the symmetric axis. The hollow coil spring includes an end wall portion, and an end face arc-shaped curved surface. The end wall portion includes an end face perpendicular to the axis. A distal-end-center closure portion is formed on the axis at the center of the end wall portion. A spring seat includes a base member and a sheet member. An end turn portion of the hollow coil spring is in contact with the sheet member. The end face of the end turn portion is opposed to a stopper wall of the spring seat.

A suspension coil spring includes a lower end turn portion, an upper end turn portion, and a helical effective portion formed between the end turn portions. The lower end turn portion includes a first portion which contacts a lower spring seat irrespective of a load, and a second portion which contacts the lower spring seat or is separated from the same according to the load. The wire diameter of the second portion is greater than that of the first portion and an average wire diameter of the effective portion. The upper end turn portion includes a third portion which contacts an upper spring seat, and a fourth portion. The wire diameter of the fourth portion is greater that of the third portion and the average wire diameter of the effective portion.

Suspension coil spring

A strut-type suspension includes a compression coil spring, a lower spring seat, an upper spring seat, and a shock absorber. The compression coil spring is disposed at a position offset to the outer side of a vehicle with respect to the shock absorber. The compression coil spring is mounted in a vehicle body in such a state that it is compressed between spring seats. The compression coil spring includes a large-diameter wire portion and a small-diameter wire portion. The large-diameter wire portion is provided in a vehicle inner-side portion of the compression coil spring. The small-diameter wire portion is provided in a vehicle outer-side portion. A wire diameter of the large-diameter wire portion is greater than a wire diameter of the small-diameter wire portion.

Strut-type suspension and compression coil spring for suspension

A knee-action-type suspension is provided with an arm member, a compression coil spring, and a shock absorber. The coil spring is extended and retracted between a full-rebound state and a full-bump state in accordance with the magnitude of a load applied to a vehicle body. A wire of the coil spring includes a large-diameter wire portion, a small-diameter wire portion, and a wire diameter varying portion. The large-diameter wire portion is provided in a first portion of the coil spring, which is on the side near to a pivot. The small-diameter wire portion is provided in a second portion of the coil spring, which is on the side far from the pivot. A wire diameter of the large-diameter wire portion is greater than a wire diameter of the small-diameter wire portion.

Suspension and compression coil spring for suspension

A compression coil spring device suitable for use in a strut wheel suspension system. The device includes a coil wire wound into a coil having an end turn. The end turn of the coil, and only the end turn of the coil, is provided with a plurality of projections along the length thereof, with the remainder of the coil wire being substantially free of projections.

Growing community of inventors

Yokohama, Japan

Masahiro Umezawa