JPS6154345A - Urgent lock retractor - Google Patents

Abstract

PURPOSE:To facilitate the releasing of a lock-up condition, by disposing a clutch mechanism between a lock means and a webbing wind-up shaft, and by providing a means for holding the driven side of the clutch mechanism in its lock condition. CONSTITUTION:Upon wind-up of a webbing W, when the wind-up rotation of a wind-up shaft 2 is abruptly stopped, a lock piece 7 meshes with ratchet teeth 11a formed in a ratch cup 11 due to the inertia of an inertia member 9 to establish a lock-up condition. In this condition, it the webbing W is to be forcedly pulled out, gaps between layers of the webbing W may be eliminated, and therefore, the webbing W may be pulled out by a slight amount. The wind-up may be made by an amount corresponding to the slight amount of the webbing W pulled out, and therefore, the shaft 2 is rotated counterclockwise, correspondingly. However, the ratch cup 11 is urged clockwise by means of a toggle spring 16, and therefore, it does not rotate in association with the rotation of the shaft. Therefore, the lock piece 7 and the teeth 11a are disengaged from each other to release the lock-up condition.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a webbing retractor equipped with an emergency locking mechanism for aircraft, automobiles, etc., and more particularly to a webbing sensing type emergency locking retractor.

The conventional webbing-sensing emergency lock retractor attaches an inertial member to the shaft around which the webbing is wound so that it can rotate relative to the shaft, and utilizes the relative rotation between the two caused by the inertial force when the webbing is suddenly pulled out. Many types include an emergency locking mechanism that prevents rotation of the shaft by engaging a ball with a latch plate coaxially attached to the shaft. In such an emergency lock retractor, when the occupant releases the buckle, the webbing is rapidly wound up by a take-up spring provided on the shaft, and the entire amount is stored in the retractor.

In this case, since the rotation of the shaft is suddenly stopped, inertia force acts and relative rotation occurs, which tends to result in a so-called lock-up state in which the webbing cannot be pulled out or wound up. To release this lockup state.

In the worst case, it is necessary to disassemble the retractor, which is extremely inconvenient.

The present invention has been made in view of the above points, and an object of the present invention is to provide an emergency lock retractor that can easily release the lock-up state with a simple mechanism.

Hereinafter, the structure of the present invention will be explained based on a specific embodiment.6 Fig. 1 is an exploded perspective view showing a webbing sensing type emergency lock retractor as a first embodiment of the present invention, and Fig. 2 is an exploded perspective view showing a webbing sensing type emergency lock retractor as a first embodiment of the present invention. FIG. The reel 1 for winding the webbing consists of latch plates lb fixed to both ends of a cylinder 1a on which the webbing is wound, and multi-shell ratchets 1b are evenly formed on the entire circumference of each launch plate 1b. has been done. This reel 1 is fitted onto a shaft 2 so as to be able to rotate integrally therewith. The shaft 2 on which the reel 1 is inserted is inserted into insertion holes 3b, 3b, which are formed in, for example, a U-shape or which are bored in opposing side plates 3a, 3a of the tractor base 3, and is rotatably supported. There is.

At one end of the shaft 2 protruding from the side plate 3a, there is a spiral bar that urges the shaft 2 and reel 1 to rotate in the webbing winding direction. , 4 are installed.

The spiral spring 4 is covered with a bowl-shaped case 5. Both ends of the spiral spring 4 are locked at appropriate positions on the inner peripheral surfaces of the shaft 2 and the case 5, respectively.

The other end of the shaft 2 is equipped with a clutch mechanism that appropriately transmits the rotation to a locking means to be described later when the change in the rotational speed of the shaft exceeds a predetermined standard. has been done. The clutch mechanism in this example is
A main moving part consisting of a flange 6, a lock piece 7 as an engaging member, a retainer 8, and an inertia block 9 as an inertia member is configured to be removably connected to a latch cup 11 as a passive part by a latch cup 11 and the lock piece 7. ing. A flange 6 is fitted to one end of a shaft 2 formed in an oval cross section so as to be rotatable therewith.

Two shafts 6a and 6b are erected on the back side of the surface of the flange 6 into which the shaft 2 is fitted. A lock piece 7 having a sharp claw portion 7a at its tip is rotatably inserted into one shaft 6a through a hole 7b bored approximately in the center, and the tip of this 1Illll 16a serves as a stopper. The retainer flange 8 is rotatably inserted into one of two holes 8a formed in the retainer flange 8. The other one! 1I16b has a disc-shaped inertia block 9 formed with a groove 9a and a notch 9b for accommodating the lock piece 7, retainer flange 8, etc., and is rotatable through a shaft hole 9c bored at its center. extrapolated to

The tip of this shaft 6b is rotatably inserted into the other hole 8b similarly bored in the retainer flange 8. FIG. 3 shows a state in which the flange 6, lock piece 7, retainer flange 8, and inertia lock 9 are assembled, viewed from the shaft 2 side. In FIG. 3, a coil spring 10 is stretched between a proper position on the claw part 7a side of the lock piece 7 housed in the groove part 9a of the inertia block 9 and a corresponding proper position on the flange 6. Therefore,
When the change in speed at which the webbing is pulled out exceeds a predetermined value, the inertia block 9 moves the shaft 2 due to its own inertia.
And the flange 6 cannot follow the rotation (arrow) of the flange 6.
rotation lag occurs.

That is, the flange 6 rotates relative to the block 9 about the shaft 6b within the range of the notch 9b.

Therefore, the lock piece 7 into which the illumination 6a is inserted
is F7.5! The tip claw portion 7a protrudes from the block 9 by sliding in the direction of the arrow along the portion 9a.

Returning to FIG. 1, the assembly consisting of the flange 6, lock piece 7, inertia block 9, and retainer flange 8 is housed in a bowl-shaped latch cup 11 that is rotatably inserted onto the shaft 2. . The inner peripheral surface of the side wall of the latch cup 11 has a ratchet @
11a is formed. And latch cup 11
An engagement pin llb is erected at a proper position on the bottom surface of the lock arm 14, which will be described later.
They are inserted loosely into the curved holes 3d drilled in the respective holes 3d. Furthermore, a protrusion 11c that locks one end of a toggle spring 16, which will be described later, is erected at a proper position on the outer peripheral surface of the side wall of the lunch cup 11. A bushing 12 made of resin, for example, is interposed between the latch cup 11 and the side plate 3a, and the latch cup 11 is prevented from coming into contact with the side plate 3a, thereby smoothing the rotation of the latch cup 11.

On the other hand, fan-shaped holes 3c, 3c are bored diagonally below the insertion holes 3b, 3b of the side plates 3a, 3a of the retractor base 3, respectively. Both ends of a stopping ball 13, which engages with the latch plate 1b described above and locks the reel 1 from rotating, are inserted into these fan-shaped holes 3c, 3c, respectively. A pair of lock teeth 13a are provided at both ends of the ball 13.
, 13a are provided protrudingly from the latch plate 1.
It meshes with ratchet teeth b and lb, respectively. Both ends of the ball 13 are formed into a plate shape with a rectangular cross section, and therefore, the ball 13 is supported in a loosely fitted state in which both ends are rotatable within the range of the central angle α of the fan-shaped hole 3G. 9
The end portion of the ball 13 in this example corresponding to the clutch mechanism described above is formed in two stages, and the tip portion 13 protrudes from the side plate 3a.
A lock arm 14 is attached to b. A rectangular hole L4a is bored at one end of the lock arm 14, into which the tip 13b of the pole 13 is fitted. An oval engagement hole 14b is bored at the other end of the lock arm 14, into which the engagement pin ll of the latch cup 11 is inserted.
b is loosely fitted. Therefore, the latch cup 11 and the shaft 2 are rotated together by the distal end pawl 7a of the lock piece 7 protruding from the inertia block 9 meshing with the ratchet teeth 11a, and the lock arm 14 is inserted into the rectangular hole through the engagement pin llb. It is engaged and rotated around the 14a side, and the pawl 13 is rotated together.

A pawl spring 15 is interposed between the pawl 13 as a locking means and the side plate 3a, and the pawl spring 15 is biased in the non-engaging direction with respect to the latch plate 1b. One end is locked in a locking hole 13c drilled in the tip part 13b protruding from the side plate 3a, and the other end is locked in a locking hole 3e drilled in the side plate 3a. The lock arm 14 is biased to rotate clockwise.

In addition, since the engagement pin 11b provided upright on the latch cup 11 is passed through the curved hole 3d of the side plate 3a through the engagement hole 14b, the lock arm 14 is at the most clockwise rotation position. is determined by the position where the engagement pin Ilb abuts the upper end of the curved hole 3d. The length of the curved hole 3d is set so that when the pawl 13 engages with the latch plate 1b, a gap can be secured between the lower end of the pawl 13 and the engagement pin llb.

Therefore, the latch cup 1 as a passive part of the clutch mechanism
A toggle spring 16 as a holding means is interposed between the toggle spring 1 and the side plate 3a. In this example, one end of the toggle spring 16 is inserted into a protrusion lie erected on the outer peripheral surface of the latch cup 11, and the other end is inserted into a hook-shaped protrusion 3f provided at an appropriate position on the side plate 3a. , the biasing direction can be switched in a toggle manner. That is, in FIG. 2, in the normal unlocked state, the toggle spring 16
uses its elastic force to bias the latch cup 11 in the counterclockwise direction, but in the event of an emergency lock, the clutch mechanism described above is connected and the latch cup 11 resists the biasing force of the ball spring 15 in the clockwise direction. When the toggle spring 16 is rotated and exceeds the neutral position (see FIG. 4a) in which the toggle spring 16 is compressed to a short radius, the biasing direction is switched to a direction that causes the latch cup 11 to rotate clockwise.

The operation of the above embodiment configured as described above will be explained below. First, the normal emergency locking operation will be explained. Webbing W suddenly occurs due to collision etc. when the belt is attached.
is pulled out and the rotational angular acceleration of the shaft 2 exceeds a predetermined value, the inertia block 9, which is loosely fitted to the shaft 2, cannot follow the rotation of the shaft 2 due to its own inertia, and the rotation lags behind the shaft 2. occurs. That is,
The shaft 2 rotates in the forward direction relative to the inertia block 9. As a result, the lock piece 7 rotatably supported by the pin 6a of the flange 6 protrudes from the inertia block 9 and meshes with the ratchet teeth 11a provided on the inner peripheral surface of the latch cup 11, causing the latch cup 11 and the shaft 2 rotate together in the clockwise direction as shown in FIG. 4a. When the latch cup 11 rotates, the lock arm 14 is engaged and rotated clockwise through the engagement pin llb against the elastic force of the pole spring 15. As a result, as shown in FIG. 4b, the pawl 13 engages with the latch plate 1b, preventing the shaft 2 from rotating clockwise and stopping the webbing W from being fed out. Also, along with this, the toggle spring 16
The latch cup 11 is tilted to the left in the figure beyond the intermediate position shown in figure a, and the latch cup 11 is biased clockwise. Due to this.

The latch cup 11 is held in the locked state (the position of Figure 4b).

When the emergency situation subsides and the pulling force no longer acts on the webbing, the shaft 2 is rotated counterclockwise by the biasing force of the spiral spring 4, and the webbing W is wound up. In this case, the rotation of the shaft 2 and reel 1 in the winding direction (counterclockwise direction) is not prevented due to the ratchet effect of the latch plate 1b and the pawl 13. When the latch plate 1b is wound up and rotated, the pole 13 is lifted by the back of the teeth of the launch plate 1b and rotated clockwise, as shown in FIG. Through this, the latch cup 11 is rotated clockwise. When the rotation of the latch cup 11 exceeds the neutral position of the toggle spring 16, the directions of action of the biasing forces of the toggle spring 16 and the ball spring 15 coincide, and the white tsuku arm 14 further rotates clockwise due to their cooperative effect. The ball 13 is reliably released from the latch plate 1b. After this, the lock piece 7 has moved to the non-engaging position, so the webbing can be smoothly fed out at the normal speed.

Next, the operation of releasing the lock-up state described above will be explained. By the way, a lockup state occurs as follows. When the occupant inadvertently releases the buckle and the entire amount of webbing is rapidly wound into the retractor, and the winding rotation v & (counterclockwise direction) of the shaft 2 suddenly stops, the inertia block 9 stops retracting the webbing due to its own inertia. direction and rotate in a counterclockwise direction relative to the shaft 2. As a result, lock piece 7
protrudes to a position where it can engage with the ratchet teeth 11a of the latch cup 11. Then, as the shaft 2 rotates slightly in the webbing payout direction (clockwise) in reaction to the sudden stop, the lock piece 7 that moves together with the shaft 2 meshes with the ratchet teeth 11a of the latch cup 11, and this state is retained. Therefore, even if an attempt is made to pull out the webbing W as shown in FIG. 4a, since the shaft 2 and latch cup 11 are connected, the latch cup 11 will rotate clockwise and the ball 13 will be pulled out as shown in FIG. 4b. The shaft 2 is engaged with the latch plate 1b, and the rotation of the shaft 2 is locked, making it impossible to draw the shaft 2 upward. Further, it is also impossible to wind up the webbing W since the entire amount is wound up. A lock-up state is a state in which the webbing cannot be rotated in both winding and unwinding.

In the lock-up state, the phase of the shaft 2 when the lock piece 7 engages with the latch cup 11 (see Fig. 4a) and the phase when the ball 13 engages with the latch plate 1b and the feeding rotation of the shaft 2 is locked (see Fig. 4a). (see Figure 4b). For this reason, webbing W
When an attempt is made to pull out the webbing W, the shaft 2 and the latch cup 11 rotate clockwise by the phase difference, and the webbing W is pulled out. In this case, the toggle spring 16 is
As shown in FIG. 4b, as the latch cup 11 rotates, it tilts to the left beyond the neutral position, urging the latch cup 11 in the clockwise direction. Furthermore, even after the drawer is locked, if you try to forcibly pull out the webbing W, the webbing wrapped in layers on the cylinder 1a of the reel 1 will be tightened and the m space between each layer will disappear, and the reel 1 Although the shaft 2 cannot be rotated, the webbing is pulled out by a certain amount.

Therefore, it becomes possible to wind up the webbing by the amount that the webbing is pulled out from the lock-up state, and as shown in FIG. 4C, the shaft 2 rotates by that amount in the direction to wind up the webbing (counterclockwise).

Here, in a conventional tractor that is not equipped with a biasing means such as a toggle spring 16, the biasing force of the ball spring 15 against the latch cup 11 is applied to the lock arm 14.
Since the latch cup 11 is acting counterclockwise through the shaft 2, the latch cup 11 also follows the rotation of the shaft 2 and rotates in the same direction.
The engagement state between the lock piece 7 and the latch cup 11 is not released.

However, in the present invention, the latch cup 11 is provided with a toggle spring 16 as a holding means, and the latch cup 1 is held in the lock-up state shown in FIG. 4b.
1 is biased clockwise. Therefore, as shown in Figure @40, the latch cup 11 does not integrally follow the counterclockwise rotation of the shaft 2, and for this reason, the engagement shape of the lock piece 7 is changed due to the elastic force of the spring 1o. i is canceled.

Further, as shown in Fig. 4d, when winding up the webbing W until the winding is locked up, the latch plate 1
The ball 13 is lifted by the back of the tooth b, the lock arm 14 is rotated clockwise, and the latch cup 1 is rotated clockwise.
1 is also rotated in the same direction. When the toggle spring 16 exceeds the neutral position and tilts to the opposite side as shown in FIG. is canceled.

Next, another embodiment of the present invention will be described.

It should be noted that the same components as in the above embodiment are given the same reference numerals and the explanation thereof will be omitted. In the emergency lock retractor of this example, as shown in FIG. 5a, a concave-convex engaging portion 21 is formed at a suitable location on the outer peripheral surface of the latch cup 11. And a leaf spring 22 as a holding means.
is fixed at a proper position on the side plate 3a. The bent tip 22a of the leaf spring 22 is located in the recess 21a of the engaging portion 21.
The fixed position is set so that occlusion is possible in the initial state. Therefore, in the non-occlusal state, due to its elasticity, a resilient force always acts to return the tooth to the initial occlusal state. The other configurations are the same as those of the above embodiment.

The lock-up release operation in this embodiment configured as described above is as follows.

From the state shown in FIG. 5a where the lock piece 7 is engaged with the latch cup 11 due to full winding, to the state shown in FIG. 5b where the ball 13 is engaged with the latch plate 1b and the feeding rotation of the shaft 2 is locked. When the webbing W is pulled out and the latch cup 11 is rotated clockwise until the webbing W is pulled out, the tip 22a of the leaf spring 22 that is engaged with the engagement portion 21 is forcibly engaged with the recess 21a.

In this state, rotation of the latch cup 11 in the counterclockwise direction is reliably prevented. Next, as shown in Figure 5C,
When the webbing W is wound up by the amount that has been pulled out, the latch cup 11 is held in the state shown in FIG. 5b by the leaf spring 22, so it does not follow the rotation of the shaft 2, and therefore the engagement state of the lock piece 7 is released. be done. After this, as shown in FIG. 5d, the ball 13 is lifted by the back of the teeth of the latch plate 1b, the latch cup 11 is rotated counterclockwise, and the leaf spring 22 and the recess 21a of the latch cup 11 are connected. Occlusion is forcibly released.

As described above in detail, according to the present invention, by providing a holding means for holding the passive side of the clutch mechanism interposed between the locking means and the webbing take-up shaft in a locked state, the driving side of the clutch mechanism is In contrast, a rotation delay can be reliably generated, and the lock-up state can be easily released using this rotation delay. Therefore, it is possible to provide an emergency lock retractor in which the emergency lock mechanism operates stably and the lock-up state can be easily and reliably released by a simple mechanism. It should be noted that the present invention is not limited to the specific embodiments described above, and it goes without saying that various modifications can be made within the technical scope of the present invention.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view showing one embodiment of the present invention, Fig. 2 is a side view showing one embodiment of the present invention, and Fig. 3 is an explanation showing main parts of one embodiment of the present invention. Figures 4a to 4d are explanatory diagrams showing the operation of one embodiment of the present invention, and Figure 5.
Figures a through 5d are explanatory diagrams showing the operation of other embodiments of the present invention, respectively. (Explanation of symbols) 1a: Cylinder 1b = Latch plate 2: Shaft 7: Lock piece 11: Latch cup 13: Lock ball 14: Lock arm 15: Ball spring 16: Toggle spring Patent applicant NSK Warner Co., Ltd. Figure 4qFigure 4bFigure 4CFigure 4dFigure 50Figure 5bFigure 5C

Claims (1)

[Claims] 1. An emergency lock retractor that automatically locks the webbing in the event of an emergency such as a collision, which includes a take-up shaft around which the webbing is wound, and a retractor that rotates the take-up shaft in a predetermined direction. a winding means for winding the webbing with the winding shaft, and a lock provided to be able to freely switch between a locked state in which the winding shaft is prevented from rotating in a direction in which the webbing is unreeled, and an unlocked state in which rotation in both directions is not prevented. a means interposed between the winding shaft and the locking means, the locking means and the winding shaft are arranged in response to a change in the rotational speed of the winding shaft due to a rapid unwinding of the webbing in an emergency. An emergency lock retractor comprising: a clutch means for coupling; and a holding means for holding a passive part of the clutch means coupled to the locking means in the locked state. 2. The emergency lock retractor according to item 1 above, wherein the holding means is a spring member that can toggle the direction in which the passive part is biased between the locking side and the non-locking side. 3. The emergency lock retractor according to item 1 above, wherein the holding means comprises an engaging part formed on the passive part and a leaf spring that can engage with the engaging part. 4. In the above item 1, the clutch means includes a driving member connected to the winding shaft, an engaging member provided on the driving member so as to be able to protrude forward and backward by inertia force, and when the engaging member protrudes, An emergency lock retractor comprising: a passive member having an engageable engaged portion formed therein;