# US 12,759,501 B2 · Seat belt buckle device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,759,501 B2 - Document ID: US12759501B2 - Status: Granted - Kind: B2 - Application number: 18/549,466 - Filed: 2021-12-09 - Published: 2024-05-30 - Granted: 2026-10-13 - Earliest claimed: 2021-03-12 - Assignees: Autoliv Development AB - Applicants: Autoliv Development AB - Inventors: Ju Sang Kang; Won Wha Ryoo - Web page: https://patentgrep.com/patent/US12759501B2 ## CPC - B60R 22/26: secured to the seat - B60R: VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR ## Abstract A seat belt buckle device includes a buckle to which a tongue is detachably coupled, a strap coupled to the lower part of the buckle and mounted at a seat frame so as to be rotatable in the forward and backward directions, a bracket which is disposed at one side of the strap and fixed to the seat frame, and which restricts the rotational angle of the strap, and a torsion spring for providing restoring force so that the strap is disposed upwards, and thus the buckle can be maintained in an erected state. Accordingly, the tongue can be easily coupled to the seat belt buckle, and noise and damage generated during the rotation of the strap connected to the buckle can be prevented. ## Claims ### Claim 1 A seat belt buckle apparatus comprising: a buckle to which a tongue is detachably coupled; a strap coupled to a lower portion of the buckle and rotatably mounted to a seat frame to rotate in a forward and backward direction; a bracket disposed on one side of the strap and fixed to the seat frame to limit a rotation angle of the strap; and a torsion spring providing a restoring force such that the strap is positioned upward, wherein the strap is formed with a through hole into which a mounting bolt is coupled to the seat frame is fastened, and an adjustment hole into which an adjustment protrusion is formed in the bracket is inserted, wherein a strap bush is coupled to the through hole, wherein the mounting bolt is coupled to a through hole of the strap bush in a state in which the torsion spring and a bush are installed on an outer peripheral surface of the mounting bolt, wherein the bush is formed on an outer peripheral surface thereof with a first step and a second step, which are configured to have a stepped surface, in which the torsion spring is coupled to the first step and supported thereon, and the strap bush is coupled to the second step of the bush, and wherein the second step of the bush is configured to have a width wider than that of the strap bush such that the bush is spaced apart from the strap bush and a first gap is defined as a width difference between the second step of the bush and the strap bush, and an outer diameter of the second step is configured to be smaller than an inner diameter of the strap bush such that a second gap is defined as a diameter difference between the outer diameter of the second step and the inner diameter of the strap bush. ### Claim 2 (depends on 1) The seat belt apparatus of claim 1, wherein the first gap is formed between a left side wall of the second step and a flange portion of the strap bush, and between a right end of the bush and a left side surface of a flange. ### Claim 3 (depends on 1) The seat belt apparatus of claim 1, wherein the second gap is formed between an outer circumference of the second step and an inner circumference of the through hole formed in the strap bush. ### Claim 4 (depends on 1) The seat belt apparatus of claim 1, wherein each of the first gap and the second gap has a size of around 0.1 mm. ### Claim 5 A seat belt buckle apparatus comprising: a buckle to which a tongue is detachably coupled; a strap coupled to a lower portion of the buckle and rotatably mounted to a seat frame to rotate in a forward and backward direction; a bracket disposed on one side of the strap and fixed to the seat frame to limit a rotation angle of the strap; and a torsion spring providing a restoring force such that the strap is positioned upward, wherein the strap is formed with a through hole into which a mounting bolt is coupled to the seat frame is fastened, and an adjustment hole into which an adjustment protrusion is formed in the bracket is inserted, wherein the adjustment protrusion is configured to be bent toward the strap at a lower end of the bracket, wherein the adjustment protrusion is provided with a protective member that covers the adjustment protrusion and is configured to be bent in order to prevent noise and scratch by covering an entire contact area between the strap and the bracket when the strap is rotated, wherein a strap bush is coupled to the through hole, wherein the mounting bolt is coupled to the through hole of the strap in a state in which the torsion spring and a bush are installed on an outer peripheral surface of the mounting bolt, wherein the bush is formed on an outer peripheral surface thereof with a first step and a second step, which are configured to have a stepped surface, in which the torsion A spring is coupled to the first step and supported thereon, and the strap bush is coupled to the second step of the bush, the bush and the strap bush are manufactured by using mutually different materials to prevent noise and damage generated during rotation of the strap. ### Claim 6 (depends on 5) The seat belt apparatus of claim 5, wherein the rotation angle of the strap is limited by a length of the adjustment hole in a forward and backward direction. ### Claim 7 (depends on 5) The seat belt apparatus of claim 5, wherein the protective member is manufactured in a tube shape by using a heat-shrinkable rubber material, and fixed to the adjustment protrusion while being shrunk by heat in a state in which the protective member is installed on the adjustment protrusion. ### Claim 8 (depends on 5) The seat belt apparatus of claim 5, wherein the bush is formed of a metal material having rigidity, and the strap bush is manufactured by using a synthetic resin material having rigidity lower than that of the bush.