JPS6037863Y2 - Emergency locking retractor - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an emergency locking retractor for a safety belt for a vehicle such as an automobile, and more particularly to a vehicle body sensing type emergency locking retractor that locks the belt by sensing acceleration applied to the vehicle body.

Many emergency locking retractors have been invented, devised, and put into practice.

Among these, an important technical problem with vehicle body sensing type glue tractors is so-called tooth skipping between the lock bar and the ratchet wheel.

This is because when the lock bar and ratchet try to engage in an emergency, the top of the lock bar accidentally collides with the top of the teeth of the ratchet, and the repulsion causes the long belt to be pulled out even further. This means that the occupants will not be adequately restrained.

Conventionally, a so-called synchronous method has been the most typical method for solving this problem of tooth skipping.

This is provided with another pair of lock bar and ratchet (often made of resin), and this lock bar and ratchet are engaged in advance, and due to these engagements, the pulling force of the reel drives the metal lock bar and is constantly The lock bar is configured so that it enters the ratchet teeth at a fixed angle and position relative to the ratchet teeth.

Other conventional examples include using multiple ratchets, lock bars, and acceleration sensing members to reduce the probability of tooth skipping, or using the repulsion caused by tooth skipping to drive the second lock bar. There are well-known methods to do this.

However, for the synchronous type, a resin ratchet and lock bar are required, and for those with multiple ratchets, lock bars, and acceleration sensing members, the second ratchet, lock bar, and acceleration sensing member are redundant. The retractor was equipped with an emergency locking retractor as a special component, and it could not necessarily be said to be superior in terms of number of parts, weight, price, and ease of assembly.

In view of the above points, the present invention has been developed by elastically accumulating the energy applied to the lock bar due to tooth skipping when the lock bar and ratchet wheel skip, and by releasing this energy, the next To provide an emergency lock type tractor that securely engages ratchet teeth.

Hereinafter, the present invention will be explained in detail with reference to embodiments shown in the drawings.

A frame 4 of the emergency lock type retractor 2 according to the present invention shown in FIGS. 1 to 4 is formed by bending a steel plate into a U-shape.

This frame 4 has circular holes 4a, 4a that support the shaft 12 of the reel 5, fan-shaped holes 4b, 4b that support the lock pole 16, support support parts 4c, 4d that fix the support 18 of the pendulum 21, and a belt. Belt guide support parts 4e, 4e for supporting the guide 26, holes 4f, 4f and a notch 4g for fixing the bracket 28, and a hole 4h and a screw hole 41 for locking the spring device 14 are formed.

Note that a notch 4j is formed on the back surface of the frame 4 in order to reduce the weight.

The belt guide 26 is formed with a long hole 26a through which the belt passes, and a protrusion 26b that engages with a hole (not shown) provided in the vehicle body in order to attach the retractor 2 to the vehicle body at a correct angle. , the belt guide support portion 4e on the upper part of the frame 4, and the hole 26 of the 4e belt guide 26.
It is inserted into C, 26c and fixed by caulking.

The bracket 28 is fixed to the frame 4 by rivets 34 and 34, with a protrusion 28a formed on the bracket 28 and a notch 4g in the frame 4 engaging with each other.

The belt guide 26 and the bracket 28 may be formed integrally with the frame 4, but they are made separately so that the design does not need to be changed depending on the type of vehicle to which the frame 4 is installed.

The reel 5 has a ratchet wheel 8 attached to one end, a collar 10 attached to the other end, and the middle part is connected by a C-shaped steel plate 6 to form an integral body, and after being housed in the frame 4, The loop portion 3a of the belt 3 is inserted through the groove 6a of the steel plate 6, and the shaft 12 is inserted through the circular hole 4a of the frame 4 to be assembled.

Note that 30 is a bushing fixed to the frame 4.

The spring device 14 is attached to one end 12 of the shaft 12.
a, and has a so-called two-axis type spring that equalizes the winding force of the spring, and the engagement between the protrusion 14a and the hole 4h of the frame 4, and the screw insertion holes 14b, 14b.
It is fixed to the frame 4 by being screwed into the screw holes 4i, 4i of the frame 14 with screws 15.15 passed therethrough.

The lock poles 16 are arranged in fan-shaped holes 4b, 4b of the frame 4.
It is supported so that it can be rotated by a small angle.

Note that an extension 41 of the fan-shaped hole 4b formed in one side wall of the frame 4 is formed so that the lock tooth 16a of the lock pawl 16 can be inserted therein.

The lock pawl 16 is formed with a protrusion 16b for abutting against the upper part of a pendulum 21 serving as a lock pawl driving means.

The support 18 of the pendulum 21 has one end connected to the frame 4.
After engaging the hole 4d of the frame 4 and engaging the protrusion 4c of the frame 4 with the hole 18b formed at the other end, the protrusion 4c of the frame 4 is caulked and fixed to the frame 4.

Further, a hole 18c into which the elastic bushing 20 is fitted is formed approximately at the center of the support 18.

As shown in FIG. 4, the elastic bushing 20 is made of an elastic material such as an elastomer such as elastic urethane, and has a dome at the bottom so that it has appropriate elasticity and does not come into contact with the shaft 22 of the pendulum 21 when the pendulum 21 is tilted. It has been gouged out.

Further, the elastic bushing 20 is formed with a suitable flange 20a and is assembled by engaging with the circular hole 18c of the support 18.

The pendulum 21 has a cap portion 22a supported above the elastic bush 20 at the top and engaged with the protrusion 16b of the lock pawl 16, and a weight 24 displaceable downward by the acceleration of the vehicle body. They are connected by a shaft 22.

The shaft 22 has a shaft expansion portion 22b having a diameter that is loosely fitted into the circular hole 20b of the elastic bushing 20 so as to prevent the pendulum 21 from moving in the lateral direction, and a stopper for moving the weight 24 upward. The stopper part 22d and the nut 3
2 and a threaded portion 22c for fixing the weight 24.

Note that 35 is a cross cover that keeps the distance between the side walls of the frame 4 constant.

The pendulum 21 may be of the type shown in FIGS. 5 and 6.

That is, in the embodiment shown in FIG. 5, lateral movement of the pendulum 21 can be prevented by an annular flange 40 formed above the bushing 30 and having a larger outer diameter than the outer diameter of the cap 22a.

The embodiment shown in FIG. 6 also prevents the pendulum 21 from moving in the lateral direction, and a flange 42 is formed at the lower part of the cap portion 22a of the pendulum 21, and a corresponding flange 44 is attached to the inside of the flange 42 with elastic material. It is formed above the bush 20, and similar effects can be obtained even with this configuration.

In the above configuration, under normal conditions, the pendulum 21 is oriented vertically and is stable as shown in FIG.

However, when a sudden acceleration is applied to the vehicle body, the pendulum 21 tilts as shown in FIG.
The protrusion 16b between the cap portion 22a and the lock pole 16
contacts and is forced to rotate.

Usually, in most cases, the ratchet tooth 8a and the lock tooth 16a
The belt engages smoothly and the belt is prevented from elongating at this stage.

However, accidentally the top of ratchet tooth 8a and lock tooth 1
When the apex of the lock pole 6a collides as shown in FIG. 8, the lock pole 16 is thrown off and rotates violently, and at the same time, the pendulum 21 also tries to swing violently.

However, as the elastic bushing 20 undergoes elastic deformation 100 as shown in FIG. 9, the entire pendulum 21 can be moved downward by a small amount.

Therefore, the lock pole 16 will not be thrown off and rotate violently.

Furthermore, the energy accumulated by the elastic deformation 100 urges the lock pawl 16 in the direction of engagement with the ratchet tooth 8a, so that it can be smoothly engaged with the next ratchet tooth.

In addition, in the above embodiment, a vehicle body sensing type glue tractor that locks the belt by sensing the acceleration applied to the vehicle body was described, but a belt pull-out speed sensing device is added to this.
It may also be a heavy-sensing type glue tractor.

As is clear from the above description, the present invention has the following effects.

(1) The lock pole driving means is a pendulum supported on a support fixed to the frame, and this pendulum is attached to the support via an elastic bushing, so even if the teeth are accidentally skipped, the next ratchet will not move. It can be reliably engaged with the teeth.

Therefore, the locking performance is good in an emergency, and the belt does not stretch out much.

(2) Since the lock pole driving means is constructed with a very simple structure, it is inexpensive, lightweight, has a small number of parts, and is easy to assemble.

[Brief explanation of drawings]

Figures 1 and 2 are front and side views showing an embodiment of the present invention, Figure 3 is an exploded perspective view of the embodiment shown in Figures 1 and 2, and Figure 4 is an illustration showing a pendulum. 5 and 6 are explanatory diagrams showing different embodiments of the pendulum, respectively, and FIGS. 7 to 9 are explanatory diagrams showing the operating states of the main parts of the present invention. 2...Retractor, 3...Belt, 4
...Frame, 5...Reel, 8...
... Ratchet wheel, 12 ... Shaft, 14 ... Spring device, 16 ...
Tatsuku Paul, 18...Support, 20...
...Elastic bushing, 20a...Flange, 2
1... Pendulum, 22... Axis, 22a.
...Cap part, 24 ... Weight, 26
...Belt guide, 28...Bracket.

Claims (1)

[Scope of utility model registration request] A frame having a U-shaped cross section, a reel for winding the belt rotatably supported by the frame, a spring for biasing the reel in the belt winding direction, a ratchet wheel fixed to the reel, and A seatbelt retractor comprising a lock pawl that engages with a ratchet wheel to stop belt extension, and a lock pawl driving means that drives the lock pawl, the lock pawl driving means being fixed to the frame. An emergency locking type retractor, characterized in that the pendulum is supported on a support, and the pendulum is attached to the support via an elastic bushing member.