JP2012201310A - Structure of attachment portion of vehicle sensor for seat belt retractor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce noises during operations of a vehicle sensor without causing the escalation of the price of a seat belt retractor.SOLUTION: The vehicle sensor 1 is mounted in a sensor storage chamber 4 of a case 3. In the case 3, a lever stopper 42 is integrally formed. The lever stopper 42 butts against a claw 8 of a sensor lever 7 to inhibit the rotation of the sensor lever 7 and prevent the claw 8 of the sensor lever 7 from excessively biting in between teeth 6 and 6 of a gear 5, when a sensor weight 11 of the vehicle sensor 1 pushes up the sensor lever 7. In the lever stopper 42, an elastically-deformable piece 48, which abuts on the claw 8 of the sensor lever 7 to absorb an impact at a collision with the claw 8 of the sensor lever 7 by elastic deformation, and a load bearing surface, which inhibits the deformation of the elastically-deformable piece by abutting on the elastically-deformable piece 48 elastically deformed by the claw 8 of the sensor lever 7, are integrally formed.

Description

The present invention relates to a mounting portion structure of a vehicle sensor for a seat belt retractor provided in a vehicle such as an automobile.

A seat belt retractor installed in a vehicle such as an automobile stops (locks) the withdrawal of a webbing (belt) when a vehicle sensor detects a change in vehicle speed at the time of a collision or the like (Patent Document 1). reference).

FIG. 16 shows a vehicle sensor 100 mounted on a case 108 of a seat belt retractor.
It is a figure which shows the vehicle sensor for seatbelt retractors.

As shown in FIG. 16, the vehicle sensor 100 is configured such that the spherical sensor weight 101 is in a repose position (sensor weight holding hole) in the sensor holder 102 during normal operation of the vehicle (when stopped or when there is no sudden speed change). 103) and will not operate.

On the other hand, as shown in FIG. 17, the vehicle sensor 100 detects the sensor weight 101 due to inertia when the vehicle traveling speed changes suddenly due to a vehicle collision or the like, and the acceleration acting on the sensor weight 101 exceeds a predetermined value. The sensor weight 101 moves from the repose position in the holder 102, and the sensor weight 101 pushes up (rotates) the sensor lever 104, and the sensor lever 1
The nail | claw 105 formed in the front-end | tip of 04 is made to bite between the teeth 107 of the gearwheel 106 attached to the webbing take-up drum. At this time (when the vehicle sensor 100 is activated), the sensor lever 104 of the vehicle sensor 100 is abutted against the lever stopper 110 of the case 108 of the seat belt retractor to which the vehicle sensor 100 is attached, and the pawl 105 is engaged with the teeth of the gear 106. The lever stopper 110 is rotated in the direction of biting between 107 and 107.
Is prevented by. As a result, the vehicle sensor 100 can prevent the rotation of the gear 106 in the webbing pull-out direction, and can start the webbing take-up drum locking mechanism (webbing locking mechanism).

However, in recent years, the quietness of the interior of an automobile has progressed, and the collision noise between the sensor lever 104 and the lever stopper 110 when the vehicle sensor 100 is operating has become more easily detected by the seat belt wearer. Reducing the collision noise between the sensor lever 104 and the lever stopper 110 is a problem.

In order to solve such a problem, the technique disclosed in Patent Document 2 (the technique of coating an elastomer on a portion of the sensor lever that collides with another member) is applied to the sensor lever 1.
04 is coated with an elastomer or a portion of the lever stopper 110 that collides with the sensor lever 104 is coated with an elastomer so that the sensor lever 104 and the lever stopper 110 are not affected. It is conceivable to reduce the noise during operation of the vehicle sensor 100 by mitigating the impact with an elastomer.

JP 2003-212086 A Japanese Patent Laid-Open No. 7-101311

However, when the sensor lever 104 is covered with an elastomer or the lever stopper 110 is covered with an elastomer, the number of manufacturing steps of the vehicle sensor 100 increases by the step of covering the sensor lever 104 with the elastomer, or the case 108. The manufacturing man-hours of the vehicle sensor increase by the process of covering the lever stopper 110 with the elastomer, resulting in a decrease in the production efficiency of the vehicle sensor 100 or the case 108, and an increase in the product price of the vehicle sensor 100 or the case 108. Vehicle sensor 100 and case 108
As a result, a new problem arises that the price of the seat belt retractor that uses the belt increases.

Therefore, an object of the present invention is to reduce noise during operation of a vehicle sensor without causing an increase in the price of a seat belt retractor.

As shown in FIG. 1 to FIG. 14, (1) when the sensor weight 11 accommodated in the sensor holder 10 moves in the sensor holder 10 due to inertia, the sensor weight 11 is made of synthetic resin. The sensor lever 7 is rotated and pushed up, and the sensor lever 7
A belt sensor 1 for a seat belt retractor configured to bite between the teeth 6 and 6 of the gear 5 attached to the webbing take-up drum and to prevent the gear 5 from rotating in the webbing pull-out direction; (2) A seat belt retractor vehicle sensor mounting portion structure comprising: a synthetic resin case 3 that supports the webbing take-up drum rotatably and has the seat belt retractor vehicle sensor 1 mounted thereon. It is about.

In the first aspect of the present invention, when the sensor weight 11 pushes up the sensor lever 7, the case 3 abuts against the claw 8 of the sensor lever 7 to prevent the sensor lever 7 from rotating, A lever stopper 42 is integrally formed so that the claw 8 of the sensor lever 7 does not bite between the teeth 6 and 6. The lever stopper 42 abuts on the claw 8 of the sensor lever 7 and the claw 8 of the sensor lever 7 is in contact with the claw 8 of the sensor lever 7.
(2) elastic deformation pieces 48 and 53 that elastically deform and absorb the impact at the time of a collision with the elastic levers, and (2) located in the deformation direction of the elastic deformation pieces 48 and 53 via gaps 50 and 54; Load receiving surfaces 51 and 55 that abut against the elastic deformation pieces 48 and 53 elastically deformed by the claw 8 and prevent deformation of the elastic deformation pieces 48 and 53 are integrally formed.

As shown in FIG. 12, the invention according to claim 2 is the invention according to claim 1, wherein the load receiving surface 51 is a concave surface, and the side corresponding to the load receiving surface 51 of the elastic deformation piece 48 is a convex surface 52.
When the elastically deformable piece 48 elastically deformed by the claw 8 of the sensor lever 7 contacts the load receiving surface 51, the convex surface 52 and the load receiving surface 51 are engaged with each other. It is characterized by becoming.

The invention of claim 3 is: (1) When the sensor weight 11 accommodated in the sensor holder 10 moves in the sensor holder 10 due to inertia, the sensor weight 11 rotates the sensor lever 7 made of synthetic resin and pushes it up. The seat belt retractor is configured so that the claw 8 of the sensor lever 7 is bitten between the teeth 6 and 6 of the gear 5 attached to the webbing take-up drum and the gear 5 is prevented from rotating in the webbing pull-out direction. Vehicle for seat belt retractor comprising: vehicle sensor 1; and (2) a synthetic resin case 3 that supports the webbing take-up drum rotatably and has the seat belt retractor vehicle sensor 1 attached thereto. This relates to the sensor mounting structure (see FIG. 1).

In the invention of claim 3, when the sensor weight 11 pushes up the sensor lever 7, the case 3 hits the claw 8 of the sensor lever 7 to prevent the sensor lever 7 from rotating. A lever stopper 42 is integrally formed so that the pawl 8 of the sensor lever 7 does not bite between the teeth 6 and 6 (see FIG. 1). Further, as shown in FIG. 15, the claw 8 of the sensor lever 7 (1) abuts on the lever stopper 42,
An elastically deformable piece 60 that elastically deforms and absorbs an impact at the time of collision with the lever stopper 42.
(2) The elastic deformation piece 60 is positioned in the deformation direction of the elastic deformation piece 60 through the gap 61 and is in contact with the elastic deformation piece 60 elastically deformed by the lever stopper 42, so that the elastic deformation piece 60
And a load receiving surface 62 that prevents the deformation of the load receiving surface 62 are integrally formed.

ADVANTAGE OF THE INVENTION According to this invention, the noise at the time of operation | movement of a vehicle sensor can be reduced, without causing the price increase of the seatbelt retractor which uses a vehicle sensor and a case as a component.

1 is a partial cross-sectional view of a seat belt retractor showing a mounting portion structure of a vehicle sensor for a seat belt retractor according to a first embodiment of the present invention. FIG. 2A is a front view of a vehicle sensor in a normal state of the vehicle (when stopped or when there is no sudden speed change), FIG. 2A is an assembly state diagram of the vehicle sensor, and FIG. 2B is a vehicle sensor. FIG. FIG. 3A is a longitudinal sectional view of the vehicle sensor 1 shown in FIG. 2, FIG. 3A is a longitudinal sectional view in an assembled state of the vehicle sensor, and FIG. 3B is a longitudinal sectional view when the vehicle sensor is disassembled. is there. 4A and 4B are diagrams showing a sensor holder of a vehicle sensor, in which FIG. 4A is a front view of the sensor holder, FIG. 4B is a left side view of the sensor holder, and FIG. 4C is a rear view of the sensor holder. 4 (d) is a plan view of the sensor holder, and FIG. 4 (e) is a back (bottom) view of the sensor holder. It is a longitudinal cross-sectional view of a sensor holder, and is a cross-sectional view of the sensor holder cut along the line A1-A1 of FIG. FIG. 6A is a longitudinal sectional view of the vehicle sensor showing the first operating state, and FIG. 6B is a longitudinal sectional view of the vehicle sensor showing the second operating state. 7A and 7B are diagrams illustrating a sensor lever of a vehicle sensor, in which FIG. 7A is a rear view of the sensor lever, FIG. 7B is a plan view of the sensor lever, and FIG. 7C is orthogonal to the lower surface side of the sensor weight retainer. FIG. 7 (d) is a left side view of the sensor lever shown in FIG. 7 (a), and FIG. 7 (e) is a sensor shown in FIG. 7 (a). It is a right view of a lever. FIG. 8A is a front view of the sensor lever, and FIG. 8B is a longitudinal sectional view of the sensor lever shown in FIG. It is a figure which shows a part of lever stopper integrally formed in the case, Fig.9 (a) is a front view before elastic deformation piece deformation | transformation of a lever stopper, FIG.9 (b) is before elastic deformation piece deformation | transformation of a lever stopper. FIG. 9C is a right side view of the lever stopper before deformation of the elastically deformed piece. It is a figure which shows the state by which the elastic deformation piece of the lever stopper was deform | transformed with the nail | claw of the sensor lever, Fig.10 (a) is a front view after elastic deformation piece deformation | transformation of a lever stopper, FIG.10 (b) is a lever stopper. FIG. 10C is a plan view after the elastic deformation piece is deformed, and FIG. 10C is a right side view after the elastic deformation piece of the lever stopper is deformed. It is a figure which shows the state which the sensor lever and lever stopper of the vehicle sensor collided, and is a figure which expands and shows a part of FIG. It is a figure which shows the modification 1 of a lever stopper, Fig.12 (a) is a front view which shows the state before a deformation | transformation of the elastic deformation piece of a lever stopper, FIG.12 (b) is a state after a deformation | transformation of the elastic deformation piece of a lever stopper. It is a front view which shows a state. It is a figure which shows the modification 2 of a lever stopper, Fig.13 (a) is the front view (front view which fractures | ruptures and shows one part) before the elastic deformation piece of a lever stopper, FIG.13 (b) is a lever stopper. FIG. 13C is a plan view before the elastic deformation piece is deformed, and FIG. 13C is a right side view of the lever stopper before the elastic deformation piece is deformed. It is a figure which shows the state by which the elastic deformation piece of the lever stopper which concerns on the modification 2 was deform | transformed with the nail | claw of the sensor lever, and Fig.14 (a) is a front view after elastic deformation piece deformation | transformation of a lever stopper. 10 (b) is a plan view of the lever stopper after the elastic deformation piece is deformed, and FIG. 10 (c) is a right side view of the lever stopper after the elastic deformation piece is deformed. It is a figure which expands and shows a part of attachment part structure of the vehicle sensor for seatbelt retractors which concerns on 2nd Embodiment of this invention, Fig.15 (a) is a state before the nail | claw of a sensor lever collides with a lever stopper. FIG. 15B is a diagram showing a state after the claw of the sensor lever collides with the lever stopper. It is a partial sectional view of a seat belt retractor showing a mounting part structure of a conventional vehicle sensor for a seat belt retractor, and shows a state before the vehicle sensor is activated. It is a partial sectional view of a seat belt retractor showing a mounting part structure of a conventional vehicle sensor for a seat belt retractor, and shows a state when the vehicle sensor is activated.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[First Embodiment]
FIG. 1 is a view for explaining an attachment portion structure of a vehicle sensor 1 for a seat belt retractor (hereinafter abbreviated as a vehicle sensor) according to a first embodiment of the present invention.

As shown in FIG. 1, a vehicle sensor 1 is mounted in a sensor housing chamber 4 of a case 3 that rotatably supports a rotating shaft 2 of a webbing take-up drum. When the vehicle sensor 1 detects an abrupt speed change of the vehicle such as when the vehicle collides, the sensor lever 7 is interposed between the teeth 6 and 6 of the gear 5 that is coaxially mounted with the rotary shaft 2 of the webbing take-up drum. The claw 8 is bitten to prevent the gear 5 from rotating in the webbing pull-out direction, and the webbing take-up drum (not shown) can be started with a lock mechanism (webbing lock mechanism). The claw 8 and the gear 5 of the sensor lever 7 constitute a ratchet mechanism.

(Overall configuration of vehicle sensor)
2 to 3 are diagrams showing the vehicle sensor 1. Of these, FIG. 2 is a front view of the vehicle sensor 1 during normal operation of the vehicle (when stopped or when there is no sudden speed change).
FIG. 2A is an assembly state diagram of the vehicle sensor 1, and FIG. 2B is an exploded view of the vehicle sensor 1. 3 is a longitudinal sectional view of the vehicle sensor 1 shown in FIG.
FIG. 3A is a longitudinal sectional view of the vehicle sensor 1 in an assembled state, and FIG. 3B is a longitudinal sectional view of the vehicle sensor 1 when disassembled.

As shown in these drawings, the vehicle sensor 1 includes a sensor holder 10 made of a synthetic resin, a sensor weight 11 made of metal contained in the sensor holder 10 and formed in a spherical shape, and one end of the sensor holder 10. The sensor lever 7 is made of synthetic resin and is mounted on the sensor weight 11 so as to be swingable.

(Sensor holder for vehicle sensor)
As shown in FIGS. 2 to 5, the sensor holder 10 includes a bottomed sensor weight receiving recess 12 that opens upward, and support shafts 15 that protrude from both side surfaces 13 and 14 on one end side of the sensor lever 7. And a pair of support legs 17 and 18 for rotatably supporting 16 (see FIGS. 7 to 8).

The sensor weight receiving recess 12 is flat, parallel to the XY direction, and has a bottom surface 20 so as to have a circular shape in plan view, and has a tapered shape for seating the sensor weight 11 on the center of the bottom surface 20. A countersink surface 21 is formed, and a through hole 22 having a smaller diameter than the opening edge on the bottom surface side of the countersink surface 21 and concentric with the countersink surface 21 communicates the internal space of the sensor weight housing recess 12 with the external space. Is formed. A countersink surface side opening edge 23 of the through hole 22 formed in the sensor weight housing recess 12 holds the sensor weight 11 in the center of the sensor weight housing recess 12. Further, the sensor weight housing recess 12
The counterbore side opening edge 23 of the through hole 22 formed in the sensor hole 11 holds the sensor weight 11 in the center of the sensor weight receiving recess 12 until the inertial force acting on the sensor weight 11 becomes a predetermined value or more. It is a resting position. Therefore, the sensor weight 11 does not move away from the center (rest position) of the sensor weight housing recess 12 and does not move in the sensor weight housing recess 12 (see FIG. 3A).

The sensor weight housing recess 12 has a substantially tapered cylindrical wall surface 25 extending from the upper surface 24 of the sensor holder 10 formed so as to be parallel to the bottom surface 20 along the Z axis (direction perpendicular to the bottom surface 20). It is connected to the bottom surface 20 via the corner surface 26. The internal space of the sensor weight housing recess 12 is formed by a bottom surface 20, a countersink surface 21, a corner surface 26, and a wall surface 25. Here, the wall surface 25 is formed so that the shape in plan view is concentric with the bottom surface 20, and is formed so that gaps are formed at equal intervals between the sensor weight 11 held at the center of the sensor weight housing recess 12. Sensor weight receiving recess 1
The sensor weight 11 held at the center of 2 can move in the sensor holder housing recess 12 by the gap. Further, the corner surface 26 has a sensor weight 1.
1 (see FIGS. 3 (a), 6 (a), and 6 (b)).

The pair of support legs 17 and 18 are formed so as to protrude from the upper surface 24 of the sensor holder 10 in the Z-axis direction (upward), and accommodate the support shafts 15 and 16 of the sensor lever 7 in a swingable manner. Shaft holes 27 and 28 are formed (see FIG. 7). The pair of support legs 17, 18
When the support shafts 15 and 16 of the sensor lever 7 are fitted into the shaft holes 27 and 28, the support shafts 15 and 16 of the sensor lever 7 can be bent and deformed in directions away from each other. 2
After being fitted to 7, 28, the original posture is elastically restored (see FIG. 7). As a result, the support shafts 15 and 16 of the sensor lever 7 are connected to the shaft holes 27 and 28 of the pair of support legs 17 and 18.
Without swinging out, the shaft holes 27 and 28 of the pair of support legs 17 and 18 are supported so as to be swingable. The pair of support legs 17 and 18 are formed such that one support leg 18 is longer in the Z-axis direction than the other support leg 17 and is easily deformed. One support leg 1
8 has an inclined surface 30 on the upper end side and the side facing the other support leg 17, and the support shaft 16 of the sensor lever 7 is simply moved along the inclined surface 30 (the other support leg It is devised so that the support shafts 15 and 16 of the sensor lever 7 and the shaft holes 27 and 28 can be easily engaged with each other by simply being pushed between them. The shaft hole 28 of one support leg 18 and the shaft hole 27 of the other support leg 17 have the same size (hole diameter) as the thickness (axis diameter) of the support shafts 16 and 15 of the sensor lever 7. The sensor lever 7 is devised so that the sensor lever 7 can be assembled to the sensor holder 10 in a correct posture.

Further, the sensor holder 10 has positioning projections 33 and 34 formed on both side surfaces 31 and 32 thereof. The positioning projections 33 and 34 are engaged with positioning recesses 35 and 36 as guide rails formed in the sensor housing chamber 4 of the case 3 (see FIG. 1).
When the vehicle sensor 1 is mounted in the sensor housing chamber 4 with the positioning protrusions 33 and 34 of the sensor holder 10 engaged with the positioning recesses 35 and 36 of the sensor housing chamber 4, It will be hold | maintained in the sensor storage chamber 4 in the positioned state (refer FIG. 1).

Further, the sensor holder 10 prevents the sensor weight 11 from coming out of the gap with the sensor lever 7 even if the sensor holder 10 rotates as much as possible until the rotation stopper 37 of the sensor lever 7 contacts the upper surface 24. The depth of the housing recess 12 is determined (see FIG. 6).

(Sensor lever of vehicle sensor)
As shown in FIGS. 7 to 8, the sensor lever 7 is fitted on both side surfaces 13 and 14 on one end side so as to be swingable in the shaft holes 27 and 28 of the support leg portions 17 and 18 of the sensor holder 10. Support shaft 1
5 and 16 are formed (see FIGS. 2 and 4). Further, on the other end side of the sensor lever 7, a sensor weight holder 38 that is placed on the sensor weight 11 accommodated in the sensor holder 10 is formed. On the lower surface side of the sensor weight retainer 38, a substantially frustoconical sensor weight accommodation surface (concave surface) 40 that contacts the sensor weight 11 is formed. The sensor weight accommodation surface 40 contacts the surface of the sensor weight 11. (See FIGS. 3 and 6). Further, the sensor lever 7 has a claw 8 protruding from the upper surface on the other end side, the tip side of the claw 8 is formed at an acute angle, and the tip side of the claw 8 is bitten between the teeth 6 and 6 of the gear 5. (See FIG. 1). The claw 8 of the sensor lever 7 is formed in a tongue shape so as to have a width dimension smaller than the width dimension of the arm portion 41 connecting the sensor weight presser 38 and the support shafts 15 and 16 (particularly, (Refer Fig.7 (a)-(c)).

Further, when the sensor lever 7 is rotated so that the sensor lever 7 is lifted against its own weight on the lower surface on one end side of the sensor lever 7, a rotation stopper that contacts the upper surface 24 of the sensor holder 10 and prevents the rotation. 37 is protrudingly formed. The rotation stopper 37 is provided with the sensor weight 1
1 is prevented from coming out of the gap between the upper surface 24 of the sensor holder 10 and the sensor lever 7.

(Case lever stopper)
As shown in FIG. 1, a synthetic resin lever stopper 42 is integrally formed on the upper part of the sensor housing chamber 4 of the case 3 made of synthetic resin. Between the tip of the lever stopper 42 and the upper opening edge 43 of the sensor housing chamber 4, the pawl 8 of the sensor lever 7 of the vehicle sensor 1 mounted in the sensor housing chamber 4 is connected to the teeth 6, 6 of the gear 5. A window 44 is formed that allows it to protrude to a position that bites in between. The lever stopper 42 abuts on the claw 8 of the sensor lever 7 lifted by the sensor weight 11 moved in the sensor weight receiving recess 12 of the sensor holder 10, prevents the rotation of the sensor lever 7, and the teeth of the gear 5. Intrusion of the nail 8 between 6 and 6 is regulated.

As shown in FIGS. 1, 9, and 11, the lever stopper 42 has a lower surface 45 parallel to the bottom surface 20 of the sensor holder 10 of the vehicle sensor 1 mounted in the sensor housing chamber 4 of the case 3. The front end 46 of the vehicle sensor 1 is mounted in the sensor housing chamber 4 of the case 3 and is parallel to the rotation axis 47 of the sensor lever 7 of the vehicle sensor 1 (FIGS. 1 and 1).
1 in the Y-axis direction). Further, the lever stopper 42 has a width dimension (dimension along the Y-axis direction in FIGS. 1 and 11) of the claw 8 of the sensor lever 7 (FIGS. 1 and 1).
1 (dimensions along the Y-axis direction).

FIG. 9 is a view showing a detailed shape of the lever stopper 42. 9A is a front view showing a part of the lever stopper 42, FIG. 9B is a plan view showing a part of the lever stopper 42, and FIG. It is a side view which shows a part.

As shown in FIG. 9, the lever stopper 42 is integrally formed with a cantilevered elastic deformation piece 48 so as to be positioned along the width direction of the lever stopper 42. When the claw 8 of the sensor lever 7 comes into contact, the elastic deformation piece 48 elastically deforms and absorbs an impact at the time of collision with the claw 8 of the sensor lever 7 (see FIGS. 10 and 11). . The elastic deformation piece 48 constitutes a part of the distal end side of the lever stopper 42 and bends and deforms in a cantilever shape with the one end side in the width direction of the lever stopper 42 as a base end (base).

Further, as shown in FIG. 9, the lever stopper 42 has a gap 5 in the deformation direction of the elastic deformation piece 48.
A load receiving surface 51 is integrally formed so as to be positioned through zero. Therefore, the elastically deformable piece 48 of the lever stopper 42 is bent and deformed by the gap 50 between the lever stopper 42 and the shock at the time of collision with the claw 8 of the sensor lever 7 can be absorbed. The load receiving surface 51 of the lever stopper 42 abuts on the elastic deformation piece 48 that is bent and deformed (elastically deformed) by the claw 8 of the sensor lever 7, thereby preventing deformation of the elastic deformation piece 48. (See FIGS. 10 and 11). The gap 50 extends along the width direction from the other widthwise end of the lever stopper 42 toward the widthwise one end, and the bottom surface 45 of the lever stopper 42.
Is a slit that passes through the tip end side of the lever stopper 42 in the plate thickness direction (direction along the Z-axis). The load receiving surface 51 is formed in parallel with the YZ plane.

(Vehicle sensor operation)
As shown in FIG. 3 (a), the vehicle sensor 1 is configured so that the sensor weight 11 is in a rest position (sensor weight holding hole) in the sensor holder 10 when the vehicle is in a normal state (when stopped or when there is no sudden speed change). A through hole 22 that functions as an opening edge 2 on the countersink surface side of the through hole 22.
3) is held and does not operate.

On the other hand, as shown in FIGS. 1 and 11, the vehicle sensor 1 has a vehicle travel speed that suddenly changes due to a vehicle collision or the like, and an acceleration that acts on the sensor weight 11 exceeds a predetermined value.
The sensor weight 11 moves from the rest position in the sensor holder 10 due to inertia, the sensor weight 11 pushes up (rotates) the sensor lever 7, and the claw 8 formed at the tip of the sensor lever 7 is used as the webbing take-up drum. It is made to bite between the teeth 6 and 6 of the attached gear 5. The claw 8 of the sensor lever 7 of the vehicle sensor 1 is connected to the lever stopper 42 of the case 3.
The elastic deformation piece 48 is abutted by the sensor weight 11. Then, the elastically deformable piece 48 of the lever stopper 42 is bent and deformed (elastically deformed), absorbs the impact at the time of collision with the claw 8 of the sensor lever 7, and the collision sound at the time of collision with the claw 8 of the sensor lever 7. Reduce. When the elastic deformation piece 48 of the lever stopper 42 is bent and deformed and abuts against the load receiving surface 51, the elastic deformation piece 48 of the lever stopper 42 cannot be bent and deformed, so that the rotation of the sensor lever 7 is prevented by the lever stopper 42. (See FIG. 10). As a result, the claw 8 of the sensor lever 7
And the tooth 6 of the gear 5 are limited to an appropriate range. Thereby, the vehicle sensor 1 can prevent the rotation of the gear 5 in the webbing pull-out direction, and can start the webbing take-up drum locking mechanism (webbing locking mechanism).

In the operation state of the vehicle sensor 1 shown in FIG. 11, when the inertial force no longer acts on the sensor weight 11, the sensor lever 7 is a gear 5 that is urged to rotate in the webbing rewind direction by a spring not shown. It rotates in a direction that reduces the swing angle when pressed and rotates in a direction that decreases the swing angle by its own weight. As a result, the sensor weight 11 is pushed by the sensor lever 7 and returned to the rest position in the sensor holder 10.

(Effect of this embodiment)
According to the mounting portion structure of the vehicle sensor 1 for a seat belt retractor according to the present embodiment,
Since the elastic deformation piece 48 formed integrally with the lever stopper 42 of the case 3 can absorb the impact at the time of collision with the sensor lever 7 of the vehicle sensor 1, the lever stopper 42 of the case 3 is used for absorbing the shock. Compared with the case of coating with an elastomer, the production efficiency of the case 3 can be increased, and the noise during operation of the vehicle sensor 1 can be reduced without causing an increase in the price of the seat belt retractor using the case 3 and the vehicle sensor 1. Can be reduced.

Further, according to the mounting structure of the seatbelt retractor vehicle sensor 1 according to the present embodiment, the claw 8 of the sensor lever 7 is equivalent to the gap 50 between the elastically deformable piece 48 of the lever stopper 42 and the load receiving surface 51. If the elastic deformation piece 48 comes into contact with the load receiving surface 51 and the elastic deformation piece 48 is prevented from being bent and deformed by the load receiving surface 51, the rotation of the sensor lever 7 is ensured by the lever stopper 42. It is possible to prevent the claw 8 of the sensor lever 7 from excessively biting between the teeth 6 and 6 of the gear 5.

(Modification 1)
FIG. 12 is a diagram illustrating a first modification of the lever stopper 42. As shown in FIG. 12A, the lever stopper 42 according to the first modification is formed so that the shape of the gap 50 (slit shape) viewed from the front side is a substantially “<” shape. The concave surface having a substantially “<” shape when viewed from the front side is a load receiving surface 51, and the convex surface 52 having a substantially “<” shape when viewed from the front side is a wall surface (load) on the gap 50 side of the elastic deformation piece 48. The surface facing the receiving surface 51). As a result, when the elastic deformation piece 48 is pressed against the load receiving surface 51 by the claw 8 of the sensor lever 7, the elastic deformation piece 48.
The convex surface 52 and the load receiving surface 51 are engaged with each other (engaged with irregularities), and the elastic deformation piece 48 is connected to the load receiving surface 5.
1 can be reliably prevented from moving along (see FIG. 12B). As a result, the bending stress generated on the base end (base) side of the cantilever-like elastic deformation piece 48 can be reduced, the durability of the vehicle sensor 1 can be increased, and the durability of the seat belt retractor can be increased. be able to. In this modification, the wall of the elastic deformation piece 48 on the gap 50 side is a convex surface so that the strength of the elastic deformation piece 48 does not decrease. In this modified example, the gap 50 of the lever stopper 42 has a shape substantially viewed from the front side of the lever stopper 42.
However, the present invention is not limited to this, and it is only necessary that the convex surface of the elastically deformable piece 48 can engage with the load receiving surface 51 in an uneven manner.

(Modification 2)
13 to 14 are diagrams showing a second modification of the lever stopper 42. As shown in FIG. 13, the lever stopper 42 according to the second modification is formed with a cantilevered elastic deformation piece 53 having both ends in the width direction (the direction along the Y-axis) as base ends. The receiving surface 55 is an elastic deformation piece 53.
It is formed so as to be positioned via a gap (slit) 54 in the deformation direction. The gap 54 of the lever stopper 42 is closed at both ends in the width direction of the lever stopper 42, is formed in parallel with the YZ plane, and penetrates the tip end side of the lever stopper 42 in the plate thickness direction (direction along the Z axis). It is formed to do. The load receiving surface 55 is formed in parallel with the YZ plane.

In the lever stopper 42 according to this modification, when the elastic deformable piece 53 is bent and deformed (elastically deformed) by the claw 8 of the sensor lever 7, the elastic deformable piece 53 receives an impact at the time of collision with the claw 8 of the sensor lever 7. Absorbs by elastic deformation. Then, when the elastically deformable piece 53 bent and deformed by the claw 8 of the sensor lever 7 contacts the load receiving surface 55, the deformation of the elastically deformable piece 53 is blocked by the load receiving surface 55 (see FIG. 14).

Even when the lever stopper 42 of this modification is replaced with the lever stopper 42 of FIG. 9 and the mounting portion structure of the seat belt retractor vehicle sensor 1 is configured, the same effect can be obtained. Note that the technical idea of Modification 1 may be applied to this modification, and the elastically deformable elastic piece 53 and the load receiving surface 5 may be engaged with each other in an uneven manner.

[Second Embodiment]
FIG. 15 is a diagram showing a second embodiment of the present invention. FIG. 15A is a view showing a state where the claw 8 of the sensor lever 7 and the lever stopper 42 are separated (state before a collision). FIG. 15B is a diagram illustrating a state after the claw 8 of the sensor lever 7 collides with the tip of the lever stopper 42.

The mounting structure of the seatbelt retractor vehicle sensor according to the present embodiment is such that the elastic deformation piece 60 that absorbs an impact when the sensor lever 7 and the lever stopper 42 collide has the sensor lever 7.
This is different from the attachment structure of the seatbelt retractor vehicle sensor according to the first embodiment in that it is integrally formed with the pawl 8.

That is, in the mounting structure of the seat belt retractor vehicle sensor according to the present embodiment, the sensor lever 7 is integrally formed with an elastic deformation piece 60 that elastically deforms and absorbs an impact at the time of collision with the lever stopper 42. The elastic deformation piece 60 constitutes a part of the claw 8.

In addition, a load receiving surface 62 is integrally formed on the claw 8 of the sensor lever 7 so as to be positioned via the gap 61 in the deformation direction of the elastic deformation piece 60. The load receiving surface 62 prevents deformation of the elastic deformation piece 60 when the elastic deformation piece 60 elastically deformed by the gap 61 by the lever stopper 42 contacts. The gap 61 extends from the upper end surface 63 of the claw 8 toward the base end side (root side) of the claw 8 (extends diagonally to the left in FIG. 15) and is orthogonal to the XZ plane. The claw 8 is divided into an elastic deformation piece 60 and a load receiving portion 64 other than the elastic deformation piece 60. The load receiving portion 64 of the claw 8 has rigidity that is not easily deformed compared to the elastic deformation piece 60, and when the claw 8 bites between the teeth 6 and 6 of the gear 5, the lever stopper 4
In cooperation with 2, the rotation of the gear 5 in the webbing pull-out direction can be surely stopped (see FIG. 1).

According to the attachment structure of the seat belt retractor vehicle sensor according to the present embodiment, the same effect as the attachment structure of the seat belt retractor vehicle sensor according to the first embodiment can be obtained.

That is, according to the mounting structure of the vehicle sensor for seat belt retractor according to the present embodiment, the elastic deformation piece 60 formed integrally with the claw 8 of the sensor lever 7 of the vehicle sensor 1 collides with the lever stopper 42 of the case 3. Since the impact at the time can be absorbed, the production efficiency of the vehicle sensor 1 can be increased as compared with the case where the claws 8 of the sensor lever 7 are covered with the impact absorbing elastomer. Thus, noise during operation of the vehicle sensor 1 can be reduced without causing an increase in the price of the seat belt retractor using the vehicle 3.

Further, according to the mounting structure of the vehicle sensor for the seat belt retractor according to the present embodiment, the lever of the case 3 is equivalent to the gap 61 between the elastic deformation piece 60 of the claw 8 of the sensor lever 7 and the load receiving surface 62. When the stopper 42 is bent and deformed, the elastic deformation piece 60 is moved to the load receiving surface 6.
2, the deformation of the elastic deformation piece 60 is prevented by the load receiving surface 62, so that the rotation of the sensor lever 7 can be reliably stopped by the lever stopper 42.
It is possible to prevent the claw 8 from excessively biting between the teeth 6 and 6 of the gear 5.

1 ... Vehicle sensor, 3 ... Case, 5 ... Gear, 6 ... Teeth, 7 ... Sensor lever,
8 ... Claw, 10 ... Sensor holder, 11 ... Sensor weight, 42 ... Lever stopper,
48, 53, 60 ... elastic deformation piece, 50, 54, 61 ... gap, 51, 55, 62 ... load receiving surface, 52 ... convex surface

Claims (3)

When the sensor weight housed in the sensor holder moves in the sensor holder due to inertia, the sensor weight rotates the sensor lever made of synthetic resin and pushes it up, and the claw of the sensor lever is attached to the webbing take-up drum. A vehicle sensor for a seat belt retractor adapted to bite between the teeth of the gear and prevent rotation of the gear in the webbing pull-out direction;
A case made of a synthetic resin that rotatably supports the webbing take-up drum and has the vehicle sensor for the seat belt retractor attached thereto,
In the mounting structure of the vehicle sensor for the seat belt retractor provided with
When the sensor weight pushes up the sensor lever, the case abuts against the claw of the sensor lever to prevent the rotation of the sensor lever, and the claw of the sensor lever bites between the teeth too much. The lever stopper that prevents it from being formed integrally,
The lever stopper is
An elastic deformation piece that abuts on the claw of the sensor lever and elastically deforms and absorbs an impact at the time of collision with the claw of the sensor lever;
A load receiving surface that is located through a gap in the deformation direction of the elastic deformation piece, abuts on the elastic deformation piece elastically deformed by the claw of the sensor lever, and prevents deformation of the elastic deformation piece;
Formed integrally,
A mounting structure for a vehicle sensor for a seat belt retractor. The load receiving surface is a concave surface, the side corresponding to the load receiving surface of the elastic deformation piece is a convex surface, and the elastic deformation piece elastically deformed by a claw of the sensor lever contacts the load receiving surface. Then, the convex surface and the load receiving surface are adapted to engage with the concave and convex portions,
The mounting structure of a vehicle sensor for a seat belt retractor according to claim 1. When the sensor weight housed in the sensor holder moves in the sensor holder due to inertia, the sensor weight rotates the sensor lever made of synthetic resin and pushes it up, and the claw of the sensor lever is attached to the webbing take-up drum. A vehicle sensor for a seat belt retractor adapted to bite between the teeth of the gear and prevent rotation of the gear in the webbing pull-out direction;
A case made of a synthetic resin that rotatably supports the webbing take-up drum and has the vehicle sensor for the seat belt retractor attached thereto,
In the mounting structure of the vehicle sensor for the seat belt retractor provided with
When the sensor weight pushes up the sensor lever, the case hits the claw of the sensor lever to prevent the rotation of the sensor lever, and the claw of the sensor lever does not bite between the teeth. The lever stopper to be formed integrally,
The claw of the sensor lever is
An elastically deformable piece that contacts the lever stopper and elastically deforms and absorbs an impact at the time of collision with the lever stopper;
A load receiving surface that is located through a gap in the deformation direction of the elastic deformation piece, abuts on the elastic deformation piece elastically deformed by the lever stopper, and prevents deformation of the elastic deformation piece;
Formed integrally,
A mounting structure for a vehicle sensor for a seat belt retractor.

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