Granted Patent B2

US 10,549,715 · App. 15/850,331 · Granted Feb 4, 2020

Abstract

Claims (31)

1. A pretensioner comprising:

a drive wheel provided with a plurality of engaging teeth for rotating a spool, the spool for winding up a webbing for fastening a passenger; and

an elongated resin component that transmits power to the drive wheel during an emergency, wherein a side surface of the elongated resin component has a cylindrical shape,

wherein, by identifying, in advance, a position of a center line of the elongated resin component, a diameter of the elongated resin component, a position of a rotation center of the drive wheel, and a number of the plurality of engaging teeth, the plurality of teeth is positioned such that, when one engaging tooth is caused to contact a tip of the elongated resin component so that an angle formed by a gear tooth surface of the one engaging tooth and a front end face of the elongated resin component is from −3 degrees to +3 degrees, another engaging tooth adjacent to the one engaging tooth in a direction opposite to a rotation direction contacts the side surface of the elongated resin component.

2. The pretensioner according to claim 1 , wherein the one engaging tooth is provided with the gear tooth surface to contact the elongated resin component in a planer manner.

3. The pretensioner according to claim 1 , wherein the elongated resin component is provided with a tapered surface to contact the gear tooth surface of the one engaging tooth in a planer manner.

4. The pretensioner according to claim 1 , wherein the elongated resin component is provided with a recess on the side surface, the recess being capable of locking a tip of the adjacent engaging tooth.

5. A seatbelt retractor comprising:

a spool for winding up a webbing for fastening a passenger; and

a pretensioner for winding up the webbing to remove a slack during an emergency,

wherein the pretensioner includes

a drive wheel provided with a plurality of engaging teeth for driving the spool, and

an elongated resin component that transmits power to the drive wheel during the emergency, wherein a side surface of the elongated resin component has a cylindrical shape, and

wherein, by identifying, in advance, a position of a center line of the elongated resin component, a diameter of the elongated resin component, a position of a rotation center of the drive wheel, and a number of the plurality of engaging teeth, the plurality of teeth is positioned such that, when one engaging tooth is caused to contact a tip of the elongated resin component so that an angle formed by a gear tooth surface of the one engaging tooth and a front end face of the elongated resin component is from −3 degrees to +3 degrees, another engaging tooth adjacent to the one engaging tooth in a direction opposite to a rotation direction contacts the side surface of the elongated resin component.

6. A seatbelt device comprising:

a webbing for fastening a passenger;

a seatbelt retractor for winding up the webbing;

a buckle positioned at a seat, and

a seatbelt tongue attached to the webbing,

wherein the seatbelt retractor includes

a spool for winding up the webbing, and

a pretensioner for winding up the webbing to remove a slack during an emergency,

wherein the pretensioner includes

a drive wheel provided with a plurality of engaging teeth for driving the spool, and

an elongated resin component that transmits power to the drive wheel during the emergency, wherein a side surface of the elongated resin component has a cylindrical shape, and

wherein, by identifying, in advance, a position of a center line of the elongated resin component, a diameter of the elongated resin component, a position of a rotation center of the drive wheel, and a number of the plurality of engaging teeth, the plurality of teeth is positioned such that, when one engaging tooth is caused to contact a tip of the elongated resin component so that an angle formed by a gear tooth surface of the one engaging tooth and a front end face of the elongated resin component is from −3 degrees to +3 degrees, another engaging tooth adjacent to the one engaging tooth in a direction opposite to a rotation direction contacts the side surface of the elongated resin component.

7. A method of manufacturing a pretensioner including

a drive wheel provided with a plurality of engaging teeth for rotating a spool, the spool for winding up a webbing for fastening a passenger, and

an elongated resin component that transmits power to the drive wheel during an emergency, wherein a side surface of the elongated resin component has a cylindrical shape,

wherein, in the method of manufacturing the pretensioner, by identifying, in advance, a position of a center line of the elongated resin component, a diameter of the elongated resin component, a position of a rotation center of the drive wheel, and a number of the plurality of engaging teeth, the drive wheel is formed such that, when one engaging tooth is caused to contact a tip of the elongated resin component so that an angle formed by a gear tooth surface of the one engaging tooth and a front end face of the elongated resin component is from −3 degrees to +3 degrees, another engaging tooth adjacent to the one engaging tooth in a direction opposite to a rotation direction contacts the side surface of the elongated resin component.

8. The method of manufacturing the pretensioner according to claim 7 , wherein a recess is formed on the side surface of the elongated resin component, the recess being for locking a tip of the adjacent engaging tooth.

Assignments (8)