JPS5839734Y2 - safety belt retractor - Google Patents

Description

[Detailed description of the invention] An emergency locking retractor used for safety belts of vehicles, etc., prevents the safety belt from being pulled out in the event of an emergency such as a vehicle collision, rollover, or sudden stop. A winding device that uses rotational inertia to rapidly pull out the belt is generally used.
．． If high-performance technology such as 3G sensing is used, when a passenger suddenly pulls out the safety belt while trying to put on the safety belt,
There was an inconvenience that the inertia function was activated, locking the belt and making it impossible to pull it out.

In addition, in a winding device that locks the belt by sensing the acceleration/deceleration of a vehicle, etc., if a sensing mechanism is provided in the winding device itself, it can provide a wide range of sensing performance, for example, from 0.3G to 1.0G. At that time, the volume of the winding device became large, which caused problems in arranging the winding device inside the vehicle.

In addition, if such a sensing mechanism is installed in a location other than the winding device, it will require a lot of electrical wiring inside the car and the winding device will have to be operated electrically, which has the disadvantage that the winding device cannot be used depending on the car model. .

Furthermore, in many of the conventional devices described above, locking is performed by engaging a pawl also made of iron to a ratchet wheel made of iron that is fixed to the belt take-up reel. This also has the drawback of limiting the ability to make the device smaller and lighter.

Therefore, the inventor of the present invention first eliminated the above-mentioned drawbacks by using Japanese Patent Application No. 54-47237, for example, 0.3
This is a so-called double safety system that has both a sensing mechanism that senses acceleration in the high performance range of G-0 and 7G and a sensing mechanism that senses acceleration of 0.7G or more, and locks the belt drawer for each. We have proposed a safety bell 1-winding device that is simple in structure and has a small number of parts, making it possible to reduce the size, weight, and cost of the device.

However, this type of safety belt has the disadvantage that when the tongs attached to the safety belt are released by an appropriate means and the belt is suddenly unwound, the inertia mechanism is activated and the belt is locked and cannot be pulled out. It was found that this occurs.

This invention aims to solve the above problems by ensuring that the belt is pulled out when the belt is pulled out, preventing the safety belt from being pulled out in the event of an emergency such as a vehicle collision, rollover, or sudden stop, and also preventing the safety belt from being accidentally locked when unwinding. It is an object of the present invention to provide a safety belt retractor that will not be damaged.

This invention will be explained with reference to embodiments shown in the drawings.

As shown in FIGS. 1 to 4, reference numeral 1 denotes a frame having a U-shaped cross section, and is attached to the vehicle floor, seat, etc. by appropriate means.

Opposing side plates IA of this U-shaped frame 1,
Through-holes 1a and ib are formed approximately in the center of IB, and a belt winding reel 3 is inserted into these through-holes 1a and ib through collar members 2A and 2B, respectively.
A shaft 4 to which is fixed is rotatably supported.

A retainer 5 is provided on the outside of one side plate 1B of the frame 1.
A spring cover 7 containing a return spring 6 is attached via a fastener such as a screw 7A.

This return spring 6 is fixed between one end 3A of the shaft 3 and the locking part 7B of the spring cover 7, and the belt winding reel 3 and the shaft 4 are moved by the arrow A indicated by the solid line in the figure by this spring 6. The reel is biased to rotate in a clockwise direction, and a safety belt 8, one end of which is fitted onto the reel, is wound around the reel.

Therefore, when the safety belt 8 is pulled out, this reel 3
And the shaft 4 will rotate in the direction of arrow B (counterclockwise) shown by the broken line in the figure.

Further, on the outside of one side plate 1A of the U-shaped frame 1, there are a plurality of locking portions 9 (12 in the figure) arranged at regular intervals around the axis of the through hole 1a. It is formed.

This locking portion 9 consists of a substantially fan-shaped groove or hole (a groove is shown in the figure), and one inner side portion 9A of the valley groove is tapered in a counterclockwise direction as required.

The tip of the shaft 4 protrudes outward from one side plate 1A, and the base end of the protrusion is a disc having a clutch plate 19 on the side and a plurality of notches 10A on the periphery. A shaped flange 10 is fixed thereto.

A plurality of these cut portions 10A (six in the figure) are provided at positions corresponding to the locking portions 9 provided on the side plate IA.

The clutch plate 19 is manufactured by pressing a spring material, and has a fitting hole 19 into which the shaft 4 is fitted.
An arc-shaped elongated hole 19B with axis A as the axis is formed, and a plurality of notches 19C are formed in the peripheral portion.

A plurality of these notches 19C are provided (six in the figure) at positions corresponding to the notches 10A provided on the flange 10, and the thickness thereof is also larger than that of the notches 10A. .

This clutch plate 19 has long holes 19B that fit into pins 10B provided on the side of the flange 10, and arbitrary notches 19C (in the figure, three places are arranged at every other place).
The pressure contact piece 19D provided on the frame 1 is bent toward the side plate 1A side of the frame 1 and pressed against the side plate 1A, and when the safety belt 8 is pulled out, the pin 10B is rotated in the direction of arrow B (counterclockwise) to the clutch plate. It rotates by coming into contact with one end 19b of the elongated hole 19B of 19 (Fig. 4a)
.

As a result, the notch 10A of the flange 10 and the notch 19C of the clutch plate 19 are configured to match.

On the other hand, when the safety belt 8 is wound up, the rotation of the flange 10 in the direction of arrow A (clockwise) causes the pin IOB to come into contact with the other end 19b of the long hole 19B of the clutch plate 19 and rotate (FIG. 4b). .

As a result, the notch 10A of the flange 10 and the notch 19C of the clutch plate 19 become mismatched, and the flange 1
The clutch plate 19 is configured to close the notch 10A of 0 and stop the protrusion 12A of the latch member 12, which will be described later.

A substantially disk-shaped latch member 12 is supported on the outside of the flange 10 via a first spring 11 so as to be freely movable with respect to the shaft 4, and this latch member 12 is press-fitted into the shaft 4 on the outside thereof. By engaging with the first locking protrusion 13A of the locking member 13, the locking member 13 is prevented from moving outward.

The latch member 12 has the same number of protrusions 12A as the notches 10A (in the figure, 6 protrusions) that are disposed corresponding to the notches 10A of the flange 10 and always mesh with the notches 10A of the flange 10.
) are provided, and the tip 12 of each protrusion 12A is provided.
A is formed to be tapered clockwise.

This latch member 12 is normally urged by the first spring 11 to a position in contact with the locking protrusion 13A, but when pushed by the action of a cam member 14, which will be described later, it moves inward. The protruding portion 12A moves by thrusting.
The distal end portion 12a of the clutch plate 10 passes through the notch 10A of the flange 10 and the notch 19C of the clutch plate 19, and engages with a locking portion 9 provided on one of the side plates.

In this case, since the locking portion 9 and the protruding portion 12A are each formed with a taper having a relative inclination, reliable engagement is achieved and rotation in the belt winding direction is not inhibited. .

Further, on the plate surface of the latch member 12, a plurality of (six in the drawings) first cam portions 12B are provided at regular intervals on the circumference.

This]th cam portion 12B is, for example, a substantially fan-shaped hole,
are formed at equal intervals at corresponding positions between the respective protrusions,
The counterclockwise inner surface of each company forms a taper that widens outward.

Here, since the protrusion 12A of the latch member 12 is always engaged with the notch 10A of the flange 10, the latch member 12 rotates together with the shaft 4, which rotates in response to the pulling out and winding operations of the safety belt 8. There is.

Outside the latch member 12, there is an inertia wheel freely supported on the first locking protrusion 13A of the locking member 13 press-fitted into the shaft 4 so as to be movable in the thrust direction. 14 are arranged.

The inertia wheel 14 has a substantially cup-like shape as a whole, and has a plurality of first ratchet teeth 1 (12 in the figure) on its outer peripheral surface.
4A, and this first ratchet tooth 14A is provided on the outer surface.
It has second ratchet teeth 14B arranged radially toward the center at a position corresponding to , and further has a second cam portion 14C on the inner surface.

Here, the second ratchet teeth 14B are provided in the same number (
In the figure, there are 12 sheets).

Specifically, as shown in FIG. 3, the second cam portion 14C is a mountain-shaped protrusion arranged to correspond to the first cam hole 12B provided in the latch member 12. , one side portion 14E of each protrusion is tapered downward in a direction opposite to the rotational direction (broken line arrow B) of the latch member 12 when the belt is pulled out.

And, such an inertia wheel 14 is usually connected to the second
The protrusion 14C, which is a cam part, is fully inserted into the hole 12B, which is a first cam part, of the latch member 12, and is biased by the second spring 15 so that its base is in contact with the root circumference of the latch member 12. .

This second spring 15 is connected to the second spring 15 of the locking member 13.
It is fixed between the locking protrusion 13B and the inertia wheel 14.

Therefore, the rotation of this inertial wheel 14 causes the latch member 12 to
If the latch member 12 is later than that, first, the latch member 12 will slide on the taper 14E of the cam projection 14C of the inertia wheel 14 in the fan-shaped hole 12B, and one of them will move along the axial direction. .

Therefore, the spring 11 (
If the elasticity of the spiral spring 14 (first spring) is made stronger than that of the spiral spring 14 (second spring) that biases the inertia wheel 14, the inertia wheel 14 will move as shown in FIG. It will move to the right (outward) (in the direction of arrow C in the figure).

Reference numeral 16 designates a cup-shaped cover attached to the side plate surface of the frame 1 with a fastener such as a screw 16A so as to cover each of the above-mentioned members, and the inner surface corresponds to the second ratchet teeth 14B provided on the inertia wheel 14. The same number of third ratchet teeth 17 (12 in the figure) are provided at the positions where the third ratchet teeth 17 mesh with each other.

This third ratchet tooth 17 is connected to the first and second ratchet teeth as described above.
When the inertia wheel 14 moves outward due to the action of the cam portion, it engages with the second ratchet teeth 14B and stops the rotation of the inertia wheel 14.

Therefore, when the rotation of the inertia wheel 14 is stopped due to the engagement of the second and third ratchet teeth 14B and 17, the latch member 12 moves to the left (inward) as shown in FIG. It will move (in the direction of the arrow).

Here, the number of third ratchet teeth 17 does not necessarily have to be the same as the number of second ratchet teeth, and it is sufficient that at least one tooth is formed.

Note that an inertial sensing device 18 (hereinafter referred to as a sensor) is housed and held at the bottom of the cover 16.

This sensor 18 has a case 18A and a case 18A.
A weight 18B swingably supported inside the case 18A
A locking piece 18D is rotatably attached to the upper part of the side plate by a pin 18C, and a hemispherical protrusion 18G is formed at the bottom of the stopper piece 18D. It is placed on the upper surface recess 18F of 18B.

Further, the locking piece 18D of this sensor 18 is normally in a position where it does not mesh with the first ratchet tooth 14A of the inertial wheel 14, but is arranged in a position where it meshes with the first ratchet tooth 14A when it is rotated upward.

Therefore, due to the inclination during acceleration and deceleration of the vehicle, etc., the weight 1BB
When the inertia wheel 14 is tilted at a predetermined angle, the locking piece 18D engages with the first ratchet tooth 14A and acts to stop the rotation of the inertia wheel 14.

Here, the sensor 18 has the relationship between each member set so as to be activated when an acceleration of about 0.3G to 0.7G is applied, such as when the vehicle suddenly stops or tilts, and other members such as The weight of the inertial wheel 14 and the relationship between the first and second springs 11 and 15 are such that when acceleration of 0.7 G or more is rapidly applied, such as during a vehicle collision, the inertial wheel 14 is pushed outward and the cover 16 is Set it so that it collides with the inner surface of.

Of the above-mentioned members, at least the frame 1, reel 3, shaft 4, flange 10, and latch member 12 are preferably made of a material with high strength, such as iron, but the other members are made of lightweight and inexpensive material. Synthetic resin materials can be used.

Next, the operation of the device of this invention will be explained with reference to FIGS. 5, 6 and 7.

When the safety belt 8 is in a normal state and pulled out at a normal speed, the reel 3, shaft 4, flange 10, latch member 12, and inertia wheel 14 rotate simultaneously with the shaft 4.

Here, the clutch plate 19 rotates with its notch 19C maintained in a position corresponding to the notch 10A of the flange 10.

At this time, the latch member 12 is not pushed by the cam protrusion 14C of the inertia wheel 14, so it does not move, and therefore the protrusion 12A of the latch member 12 is engaged with the locking part 9 of the side plate 1A of the frame 1. Never.

In this way, the safety belt 8 is elastically pulled out and retracted in accordance with the movements of the occupant.

Next, as shown in FIG. 5, when a load of about 0.3G to 0.7G is applied due to a sudden stop or incline of the vehicle, the locking piece 18D is moved upward by the tilt of the weight 18B of the sensor 18. moving, the first ratchet tooth 1 of the inertia wheel 14
It meshes with one of the arbitrary parts of 4A.

At this time, acceleration is applied to the occupant and the safety belt 8 is about to be pulled out, causing the shaft 4, the flange 10 fixed to the shaft 4, the latch member 12, and the clutch plate 19
, respectively, but the inertia wheel 14 does not rotate.

At this time, since the elasticity of the first spring 11 is set to be stronger than that of the second spring 15, the first cam portion 12B of the latch member 12 as described in FIG.
Due to the interaction between the second cam portion 14C of the inertia wheel 14 and the second cam portion 14C of the inertia wheel 14, the inertia wheel 14 is first pushed outward and comes into contact with the inner surface of the cover 16, so that each of the second and third ratchet teeth 14B and 17 meshing occurs, and outward movement of the inertia wheel 14 is prevented.

In this case, the second and third ratchet teeth 14B, 17
Since they are provided in the same number and at the same intervals so that they can be synchronized with each other, their meshing can be performed reliably and smoothly.

Then, at the stage when the movement of the inertia wheel 14 in the thrust direction is blocked, the cam portion 12B of the latch member 12 is pushed by the cam portion 14C of the inertia wheel 14, and the latch member 12 is thereby is pushed to the left as shown in the figure.

As a result, the protruding portion 12A of the latch member 12 passes through the cutout portion 19C of the clutch plate 19 and engages with the locking portion 9 of the frame 1, so that the safety belt 8 is locked.

In this case, the protruding portion 12A of the latch member 12 and the locking portion 9 of the frame 1 that receives the protruding portion 12A are provided with corresponding tapers, and the respective members are arranged in correspondence, so that
The engagement will be performed smoothly and reliably.

Next, as shown in Fig. 6, due to a vehicle collision, etc., the
．． If an acceleration of 7 G or more is rapidly applied, the inertia wheel 14 will lag behind the rotation of the shaft 4.

In this case as well, as described above, the cam portion 12 of the latch member 12
B and the cam portion 14C of the inertial wheel 14 first causes the inertial wheel 14 to move outward,
Rotation is prevented by the ratchet teeth 14B meshing with the ratchet teeth 17 of the cover 16.

Thereafter, the safety belt 8 is finally locked in the same manner as in the case shown in FIG. 5.

In this way, the withdrawal of the safety belt 8 is reliably locked even in the case of incomplete activation of the sensitive sensor 18.

In addition, if the tongue attached to the safety belt 8 is removed from a buckle or the like (both not shown), the safety belt may suddenly be rewound and the drawer of the safety belt 8 may be locked (malfunction). be.

That is, when the safety belt is suddenly unwound, the rotation of the latch member 12 and the rotation of the inertia wheel 14 are shifted from each other, as in the case of sudden withdrawal, so that the latch member 12 is pushed by the cam portion 14C of the inertia wheel 14. At the unwinding limit point (i.e., the point at which the tongs or the like becomes a stopper and no further unwinding occurs), the shaft 4 does not rotate any further, so that the protruding portion 12A of the latch member 12 is rotated in exactly the same manner as in the case of sudden withdrawal described above. It engages with the locking part 9 of one frame, and the subsequent belt drawer is locked.

It may become unusable. However, the present invention provides the latch plate 19 as described above to eliminate this drawback.

That is, as shown in FIG. 7, when the safety belt 8 is unwound, the clutch plate 19, which is slidably provided on one side of the flange 10 fixed to the shaft 4 via a pin 10B, is fixed to the length of the elongated hole 19B. As a result, the safety belt 8 is rotated in the same direction (rewinding direction) with the flange 10 with a delay of 10 minutes, and the notch 10A of the flange 10 and the notch 19C of the clutch plate 19 do not match. (The state shown in FIG. 4 above), the notch 10A of the flange 10 is closed, and the movement of the protrusion 12A of the latch member 12 is prevented by the clutch plate 19.

As a result, the flange 10 and the inertia wheel 1 are suddenly unwound.
Even if a speed difference occurs between the latch member 12 and the latch member 12, the latch member 12 is prevented from thrusting, and the erroneous locking operation at the undesired time is reliably ignited.

In any case, when the vehicle and the occupant return to their original positions, the sensor 18 returns, and the latch member 12 and inertia wheel 14 return to their original positions due to the biasing forces of the springs 11 and 15. The safety belt 8 will be unlocked.

By the way, in any case in the above operation, the number of locking portions 9 provided on the side plate 1A of the frame 1 and the second ratchet teeth 14B formed on the side surface of the inertia wheel 14 are determined.
Since the numbers are the same and correspond to each other, the engagement between the protruding portion 12A of the latch member 12 and the locking portion 9 can be synchronized, and the belt can be quickly and reliably prevented from being pulled out. It is something.

It should be noted that the above embodiment is merely an example, and it goes without saying that each member can be replaced with another member having the same function.

As described in detail above, according to the device of this invention, when the occupant fastens the safety belt, the belt will not be locked even if the belt is pulled out quite suddenly, and in an emergency, the vehicle body detection and belt pullout detection will be activated. The double safety system allows the belt to be completely locked, and it has an extremely simple structure, and many of the parts are made of synthetic resin, which contributes to the miniaturization and weight reduction of the device. It is something that can be done.

In addition, even when the safety belt is suddenly unwound after disengaging the tongs or the like attached to the safety belt, the rotation of the clutch plate 19 closes the notch 10A of the flange 10 and the latch member It has excellent effects such as being able to reliably block the thrust movement of the belt and prevent the belt drawer from being locked. It is.

Note that if the occupant changes his/her posture after pulling out the safety belt 8 and putting it on, the safety belt 8 may be slightly unwound. If the notch 10A of 10 is closed, there is a risk that the locking function will be hindered in the event of a collision. It is desirable that the clutch plate 19 cannot easily slide on the flange 10 except during rewinding.

[Brief explanation of drawings]

FIG. 1 is an exploded perspective view showing an embodiment of the device of this invention;
Figure 2 is a partially cutaway sectional view showing the assembled state;
The figure is a schematic perspective view showing an example of the configuration of an inertia wheel used therein, Figures 4a and 4b are explanatory diagrams of the clutch plate, and Figures 5, 6, and 7 respectively show the operation of the device of this invention. FIG. 2 is a sectional view for explaining. 1... Frame, 3... Belt take-up reel, 4... Shaft, 8... Safety belt, 9... Locking Part, 10...Flange, 10A...Notch part, 11...First spring, 12...Latch member, 12A
...Protrusion part, 12B...First cam part, 14...Inertia wheel, 14A...
First ratchet tooth, 14B...Second ratchet tooth, 14C...Second cam portion, 15...
...Second spring, 16...Cover, 1
γ...Third ratchet tooth, 18...
Inertial sensing device, 19...Clutch plate, 1
9C...Notch, 10B...Pin, 1
9B... Arc-shaped long hole.

Claims (5)

[Scope of utility model registration request] (1) One end of the safety belt is fixed to a belt take-up reel that is fixed to a shaft that is suspended between both sides of the U-shaped frame, and the belt is pulled out against the biasing force of an elastic spring. In a belt winding device that is stored so as to be able to be unwound by the biasing force of a spring, a plurality of locking portions are arranged circumferentially at predetermined intervals on one side plate of the frame, and a plurality of locking portions are provided on one side plate of the frame, and protrude from the side plate. a flange that is fixed to a shaft and has a plurality of notches formed at predetermined intervals on the circumference, and a flange that is provided with a plurality of notches on the outer circumference and rotates at a predetermined angle toward the frame side of the flange; When the flange rotates, it rotates in the same direction behind the flange rotation, so that the notch of the flange matches the notch of the outer circumference when unwinding, and the notch of the flange coincides with the notch of the outer periphery when unwinding. and a notch in the outer circumference of the clutch plate, which constantly meshes with the notch in the flange, passes through the locking part and the notch in the clutch plate, and engages with the locking part in the side plate. a latch member movably supported by the shaft, the latch member having a plurality of first cam portions disposed at predetermined intervals on the circumference, and a protruding portion that moves between an engaged position and an unengaged position; a first biasing member inserted between the flange and the latch member and biasing the latch member to a position where the protrusion of the latch member does not normally engage with the locking portion of the side plate; It has a plurality of second cam parts corresponding to the first cam parts on its inner surface, first ratchet teeth arranged at predetermined intervals on its outer peripheral surface, and an inertia wheel that is freely supported on the shaft and has second ratchet teeth formed thereon; and a cover that is fixed to the frame and has third ratchet teeth on its inner surface that can mesh with the second ratchet teeth; a second biasing member inserted between the inertia wheel and the cover and urging the inertia wheel to a position where the second ratchet teeth of the inertia wheel and the third ratchet teeth of the cover do not normally mesh; and the inertia wheel. and an inertial sensing device having a locking piece that can engage the first ratchet tooth in response to the acceleration/deceleration of the vehicle, and the latch rotates when the safety belt is rapidly pulled out when the vehicle suddenly decelerates. The cam portion of the latch member is controlled by either a rotation delay due to the inertia of the inertia wheel itself than the rotation of the member, or control of the inertia wheel by the engagement of the locking piece with the first ratchet tooth in response to the sensing of the inertia sensing device. is pushed by the cam part of the inertia wheel, and its protruding part penetrates the notch part of the clutch plate and engages with the locking part, thereby locking the rotation of the belt winding IJ-ru. Safety belt retractor. (2) The safety belt retractor according to claim 1, wherein the first cam part and the second cam part each have a taper that is inclined in a direction opposite to the direction in which the belt is pulled out. . (3) Registration of a utility model characterized in that the number of the locking portions and the number of teeth of the second ratchet teeth are the same, thereby synchronizing the engagement between the protruding portion of the latch member and the locking portion. A safety belt retractor according to claim 1. (4) The safety belt retractor according to claim 1, which is a registered utility model, characterized in that the urging force of the second urging member is set to be weaker than the urging force of the first urging member. (5) The inertial sensing device includes a locking piece that moves between a position where it engages and a position where it does not engage with the first ratchet teeth of the inertial wheel, and a weight that tilts when the vehicle accelerates or decelerates,
The safety belt retractor according to claim 1, wherein the locking piece is actuated by the inclination of the weight.