JPH0322046Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field The present invention is a seat belt retractor installed in a vehicle such as an automobile, and in particular, a so-called emergency lock retractor that senses the deceleration of the vehicle and emergency locks the rotation of a webbing take-up shaft. This invention relates to a sensor box mounting structure.

PRIOR ART Various types of emergency locking retractors are known, but all of them basically detect the deceleration of the vehicle using a sensor installed in the housing, and connect the clutch member of the locking mechanism to lock the lock. The actuating input is transmitted to the mechanism to emergency lock the rotation of the webbing take-up shaft. An example of this emergency lock retractor will be explained with reference to FIGS. 1 to 3. Reference numeral 1 denotes a U-shaped housing, on which a webbing take-up shaft 2 is rotatably supported. One end of a seat belt (not shown) is anchored to a webbing take-up shaft 2, and the webbing take-up shaft 2 is biased in the winding direction by a spiral spring (not shown) that is attached to one end of the webbing take-up shaft 2. . A sensor S for sensing the deceleration of the vehicle is disposed on one side of the housing 1. This sensor S includes a sensor box 3 fixed to the side of the housing,
It consists of a rocking body 4 disposed in the sensor box 3 and a pawl 5 pushed by the rocking body 4. In this example, the sensor box 3 is used as the oscillator 4.
The figure shows a standman type that swings within the sensor box, and when a predetermined deceleration occurs in the vehicle and the swinging body 4 swings, the free end of the pawl 5, which is pivotally supported on the bracket 6 of the sensor box 3, The portion is pushed up to engage a clutch member of a locking mechanism which will be described later. The lock mechanism 7 is disposed coaxially on one end side of the webbing take-up shaft 2 that passes through the housing 1, and the lock mechanism 7 is cut on a circumference centered on the shaft 2 penetration part of the housing 1. A plurality of raised lock pawls 8, a disk 9 fixed to the 2nd end of the shaft, a circular tray-shaped clutch member 10 loosely attached to the small diameter portion 2a of the 2nd end of the shaft, and a loosely attached inner boss portion 11 of the clutch member 10. the inertia plate 12 and the lock plate 13, and the reset spring 1 that maintains the distance between the lock plate 13 and the disk 9.
4. It is roughly composed of a circular tray-shaped lock housing 15 that surrounds these various functional parts. A clutch member 10 is provided at the periphery of the disk 9.
A plurality of leg pieces 16 are bent toward the side. On the other hand, this clutch member 10 has ratchet teeth 17 on its outer periphery that engage and disengage from the pawl 5 of the sensor S.
In addition, a plurality of cam portions 18 are cut out in the boss portion 11. In addition, an inner tooth 19 that engages with the cam portion 18 is provided on the inner periphery of the lock plate 13 loosely attached to the boss portion 11, and an inner tooth 19 that engages with the cam portion 18 is provided on the outer periphery of the lock plate 13.
Outer teeth 20 are protrudingly provided, which engage with the lock pawl 8 when moved toward the disk 9 by the cam portion 18. Furthermore, the clutch member 10 has an opening 21 formed on its circumferential side.
, the clutch member 10 and the inertia plate 12
A pawl 22 is provided which is pushed outward by the inertia plate 12 and protrudes against the force of the set spring 23 due to the rotational difference between the lock housing 15 and the lock housing 15. Ratchet teeth 24 are formed. According to this emergency locking retractor, in the event of a vehicle collision, the seat belt is pulled out as the belt wearer moves forward, and the webbing take-up shaft 2 rotates in the belt retracting direction, but at this time, the deceleration at the time of the collision As a result, the rocking body 4 of the sensor S swings and flips up the pawl 5, causing the ratchet teeth 1 on the outer periphery of the clutch member 10 to swing up.
7 to restrain the movement of the clutch member 10. As a result, a rotation difference occurs between the clutch member 10 and the inertia plate 12, and the clutch member 1
At the same time as the free rotation of the clutch member 10 is stopped, the pawl 22 is projected outward by the inertia plate 12 and engaged with the ratchet teeth 24 of the lock housing 15, thereby completely restraining the movement of the clutch member 10. When the clutch member 10 stops rotating, the inner tooth 19 of the lock plate 13 rides on the cam portion 18 and moves toward the disk 9 against the force of the reset spring 14, and the outer tooth 20 moves toward the base side of the leg piece 16 of the disk 9. It also engages with the lock pawl 8.
This series of actions is carried out at the instant when the pawl 5 of the sensor S engages with the ratchet teeth 17 of the clutch member 10, and the rotation of the webbing take-up shaft 2 is urgently locked to stop the belt from being pulled out and the belt is removed. This makes it possible to securely restrain the wearer in the seat and avoid a secondary collision.

By the way, in this conventional structure, since the sensor box 3 of the sensor S is fixed to the side surface of the housing 1 with screws 25, it is difficult to fix the sensor box 3 with the screws 25 in addition to assembling the locking mechanism 7. It is undeniable that not only the number of man-hours increases, but also the number of man-hours for parts management increases, resulting in a cost disadvantage.

In view of the conventional situation, the present invention has been proposed to enable the sensor box to be attached with one touch, and to effectively utilize the input acting in the axial direction of the pawl when the pawl is engaged with the clutch member to prevent the sensor box from falling off. It is an object of the present invention to provide a sensor box mounting structure for a seatbelt retractor that allows reliable mounting.

Structure of the Invention In order to achieve the above object, in the present invention, a sensor box is attached to the lower side of the clutch member of the locking mechanism, which is disposed on the side surface of the housing and coaxially with the webbing take-up shaft that protrudes outward. ,
A oscillator is disposed within this sensor box, and a pawl is provided, one end of which is pivotally supported on the upper edge of the sensor box, and whose middle portion is placed on the top surface of the oscillator and is pushed by the oscillator. The deceleration of the vehicle is sensed by the rocking of the rocking body, the pawl is pushed, the pawl is engaged with the clutch member of the lock mechanism, and the clutch member is restrained, thereby actuating the lock mechanism. In a structure in which the rotation of the webbing take-up shaft is urgently locked by transmitting input, the engagement is caused by the engagement between a pawl disposed in the sensor box from the lower edge of the housing and a clutch member of the locking mechanism. A notch is formed so that the extended side of the input line forms an obtuse angle with respect to the input line that passes through the pivot point of the pawl from the intersection point and acts in the pawl axial direction. An engaging rail is provided protruding at an inclined angle, and this engaging rail is press-fitted into and engaged with the notch.

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings, with the same reference numerals assigned to the same parts as in the conventional structure.

That is, in the present invention, as shown in FIGS. 4 to 7, a clutch member 10 of a locking mechanism to be described later is disposed coaxially with a webbing take-up shaft 2 protruding outward from the side surface of the housing 1. The oscillator 4 is disposed in the sensor box 3 attached to the side, one end is supported by a bracket 6 on the upper edge of the sensor box 3, and the middle part is placed on the upper surface of the oscillator 4. A pawl 5 is disposed to be pushed by a rocker, and the deceleration of the vehicle is sensed by the rocking of the rocker 4, and the pawl 5 is pushed.
A circular tray-shaped clutch member 10 of the lock mechanism 7 is arranged coaxially with the webbing take-up shaft 2.
By engaging with the ratchet teeth 17 on the outer periphery and restraining the movement of the clutch member 10, the actuating input is transmitted to the locking mechanism 7 and the rotation of the webbing take-up shaft 2 is emergency locked. Then, input lines F and L acting on the housing 1 from the lower edge thereof in the axial direction of the pawl 5 passing from the engagement point to the axial fulcrum of the pawl 5 due to the engagement between the pawl 5 and the clutch member 10 are applied. This input line F.
Two parallel notches 30 are formed facing the extension side angle θ of L at an obtuse angle (90° or more), while two parallel notches 30 are formed on the back of the sensor box 3 at the same inclination angle as the notches 30. A protruding engaging rail 31 is provided, and the engaging rail 31 is press-fitted and slid into the notch 30 from the opening thereof to be engaged.

Here, the aforementioned locking mechanism 7 locks the pawl 22 by the action of the inertia plate 12 when the rotation of the clutch member 10 is stopped, as shown in FIGS. 1 to 3.
The movement of the clutch member 10 is completely restrained, and the lock plate 13 is moved toward the disk 9, and the lock plate 13, the disk 9, and the lock pawl 8 of the housing are engaged with each other, so that the shaft 2 can be moved in an emergency. shall be locked.

According to the structure of the above embodiment, the oscillating body 4 oscillates to sense deceleration during a vehicle collision or sudden braking, and flips up the pawl 5 to engage the pawl 5 with the ratchet teeth 17 of the clutch member 10. When the pawl 5 is engaged with the clutch member 10, an input is applied in the axial direction of the pawl 5 through the pivot point of the pawl 5, but on the extension side of the input lines F and L. Since the angle θ with the notch 30 is obtuse and the engagement rail 31 is engaged with the notch 30, the component force of the input is applied to the sensor box 3 diagonally upward, that is, the engagement rail 31 is engaged with the notch 30. 31 acts in the direction of biting into the notch 30. Therefore, the above-mentioned input can be effectively used to prevent the sensor box 3 from falling off, and the sensor box 3 can be mounted as securely as conventional screws. Also, sensor box 3
When assembling, the work is extremely simple, as it can be done in a so-called one-touch operation by simply pushing the engaging rail 31 into the notch 30 through its opening.
Moreover, since the notch 30 is formed obliquely upward from the lower edge of the housing 1, this is very advantageous in terms of preventing the sensor box 3 from slipping down. In particular, as in this embodiment, the two engagement rails 31, 31 on the back surface of the sensor box 3
In between, a wedge-shaped hook portion 32 having a flange portion on the lower side is formed, and a locate hole 33 is formed in a portion of the housing 1 corresponding to the hook portion 32, and the hook portion 32 is dropped into the locate hole 33. By fully engaging, the retainer can be completely secured.

These hook portions 32 and locate holes 33 are
This is very effective as a measure to prevent the sensor box 3 from coming off during subassembly to the retractor housing 1, but the locking mechanism 7 and the sensor S are entirely covered with the cover 34 to prevent the sensor box 3 from coming off. Since the cover 34 comes close to or comes into contact with the lower edge, the hook portion 32 and the locate hole 33 may be omitted in some cases.

In this embodiment, a standman type sensor is shown as the sensor S, but the sensor S can also be similarly applied to a so-called pendulum type sensor in which the rocking body swings. Further, the locking mechanism 7 is not limited to the one described in the above embodiment, but may be one that can emergency lock the webbing take-up shaft 2 by restraining the movement of the clutch member by the pawl 5 of the sensor S. That's fine.

Effects of the invention As described above, according to the invention, the sensor box can be pushed into the notch from the lower edge of the housing with a single touch, and when the lock is activated, it is engaged by the engagement between the pawl and the clutch member. By effectively utilizing the input that passes through the pawl's pivot point from the mating point and acts in the pawl's axial direction, it is possible to apply a component force to the sensor box in the direction that the engagement rail bites into the notch, thereby obtaining sufficient mounting strength. Despite its simple structure, it has great practical effects.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view of a retractor with a conventional structure, Fig. 2 is a perspective view of the clutch member of the retractor seen from the back side, and Fig. 3 is a sectional view showing the main parts of the locking mechanism of the retractor. Fig. 4 is a side view of the retractor having the structure of the present invention, Fig. 5 is a plan view of the sensor box, Fig. 6 is a view taken in the direction of the arrow in Fig. 5, and Fig. 7 is a view taken in the direction of the arrow in Fig. 6. be. DESCRIPTION OF SYMBOLS 1... Housing, 2... Webbing take-up shaft, 3... Sensor box, 4... Rocking body, 5
... Paul, 7 ... Lock mechanism, 10 ... Clutch member, 30 ... Notch, 31 ... Engagement rail.

Claims (1)

[Scope of utility model registration request] A sensor box is attached to the lower side of the clutch member of the lock mechanism, which is arranged coaxially with the webbing take-up shaft that protrudes outward from the side surface of the housing. One end is pivoted on the upper edge,
Further, a pawl is disposed whose intermediate portion is placed on the upper surface of the rocking body and is pushed by the rocking body, and the deceleration of the vehicle is sensed by the rocking of the rocking body to push the pawl. In the structure, the rotation of the webbing take-up shaft is urgently locked by transmitting an operating input to the lock mechanism by engaging the pawl with the clutch member of the lock mechanism and restraining the clutch member. From the lower edge of the housing, the extended side of the input line is directed at an obtuse angle with respect to the input line that passes through the pawl's pivot point and acts in the pawl axial direction from the engagement point of the pawl and the clutch member. A seat belt characterized in that a notch is formed, and an engagement rail is provided protruding from the back surface of the sensor box at the same inclination angle as the notch, and the engagement rail is press-fitted into and engaged with the notch. Retractor sensor box mounting structure.