JP2602712Y2 - Spring spring unit for seat belt and retractor - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mainspring spring unit of a seatbelt retractor, and more particularly to a temporary assembly mechanism of a mainspring spring unit used for assembling a seatbelt retractor.

[0002]

2. Description of the Related Art A retractor for a seat belt attached to a seat of a vehicle or the like is provided so that the webbing is automatically wound up when an occupant releases the seat belt.
The mainspring spring unit is assembled. That is, a mainspring unit that stores a biased spring is connected to a spindle that supports a winding drum around which the webbing is wound.

Conventionally, a spring unit for such a seat belt retractor has been disclosed in Japanese Utility Model Laid-Open No. 60-1196.
No. 67 is provided. This is one end (outer end) of a spring in a bottomed casing
The opening of the casing is closed by a plate, and the other end (inner end) of the spring is locked in a locking groove of a spring shaft inserted through an insertion hole provided in the plate. Insert a jig into the fitting hole of the spring shaft, insert a stopper into a circular insertion hole provided in the bottom plate of the casing while applying a biasing force to the mainspring, and fit the engaging projection of this stopper into the cylinder of the spring shaft. In this configuration, the engaging piece of the stopper is engaged with the notch portion of the casing provided on the peripheral surface of the circular insertion hole, while being engaged with the engaging concave groove provided on the peripheral edge portion. Then, the jig is removed in this state to provide a mainspring spring unit in which the urging force in the webbing winding direction is applied to the mainspring. When attaching the mainspring spring unit to the seatbelt retractor, the tip of the spindle is fitted into the fitting hole of the spring shaft, and then the stopper is removed to apply a winding force to the webbing.

[0004]

In the above-mentioned publication, a spring shaft is inserted into a through hole of the plate while one end of a mainspring is locked in the casing and the opening of the casing is closed by the plate. Therefore, since the spring shaft is locked to the other end of the mainspring, there has been a problem that the positioning operation of the locking portion is difficult. In addition, since the spring shaft is merely inserted through the insertion hole provided in the plate and engages the engagement projection of the stopper with the engagement groove provided in the cylindrical peripheral portion of the spring shaft, the biasing force is applied. If the spring unit is accidentally dropped, the spring shaft may come off from the stopper and come off from the plate. Then, when the spring shaft comes off, the wound mainspring spring is released at once, which is dangerous, and there is also a risk that the mainspring spring unit may be damaged. Furthermore, when the spring unit is assembled to the retractor, the spring shaft loses engagement with the stopper and has a cantilever structure that is supported only by the plate insertion holes. Had also. Furthermore, after removing the stopper, a circular insertion hole for attaching the stopper provided on the bottom plate of the casing is opened, so that the circular insertion hole is closed so that foreign matter does not enter the spring unit. There is also a problem that a cap must be provided.

The present invention has been made in view of the above-mentioned problems of the prior art, and has as its object the object of being that it is easy to assemble and that even if the spring unit is dropped, Accordingly, the present invention aims to provide a spring spring unit of a seat belt retractor which does not cause the spring spring to pop out, does not damage the spring spring unit, and has high durability.

[0006]

In order to achieve the above object, a spring spring unit of a seat belt retractor according to the present invention is provided with a spring having a stepped portion at the center of a bottom plate for receiving and storing one end of a spring. A casing provided with a hole, the other end of the mainspring is locked, and a distal end provided with an insertion hole is rotatably engaged with the step portion, and a fitting hole provided at a base end winds the webbing. A spring shaft which is fitted with the tip of the spindle to be supported and has a flange edge formed on the base end side, and a base end portion of the spring shaft is rotatably fitted at the center, and is larger than an outer diameter of the flange edge of the spring shaft. A small insertion hole is provided, and a plate that engages with the casing and closes the opening of the casing is provided, and a shaft rod that fits into the insertion hole and a peripheral side plate that stands upright from a peripheral edge of a bottom plate of the casing .
A stopper provided with a locking piece abutting on a bent wall portion formed on an outer wall surface, and a shaft rod of the stopper is fitted into a through hole of a casing and an insertion hole of a spring shaft in a state where a biasing force is applied to a mainspring, bending the engaging piece of the stopper of the casing
By contacting the curved wall portion , the biasing state of the mainspring is maintained. Further, a continuous guide groove is provided in the bent wall portion of the casing, and a locking piece having an L-shaped cross section formed at the end of the stopper is engaged with the guide groove and comes into contact with the bent wall portion.

[0007]

The mainspring is housed in the casing with one end thereof being locked to the casing and the other end thereof being locked to the spring shaft. The operation of locking the spring shaft to the mainspring can be performed easily before closing the opening of the casing with the plate. The spring shaft is rotatably supported at the distal end and the base end of the casing with the stepped portion of the casing and the insertion hole of the plate, and even if an impact is applied,
The spring shaft is formed with a flange edge having an outer diameter larger than the insertion hole of the plate, so that it does not come off. Also, even if the stopper is removed after assembling into the retractor, the through hole for inserting the stopper in the casing is substantially closed by engaging the tip of the spring shaft with the step provided on the casing bottom plate. No foreign matter is mixed. Then, in a state where the urging force in the webbing winding direction is applied to the mainspring, the stopper of the stopper fits into the through hole of the casing and the insertion hole of the spring shaft, and the locking piece guides the guide groove into the guide groove of the casing. Since the spring device is pressed against the bent wall portion, the stopper does not come off even when the spring device is dropped, and the spring device can be provided in a temporarily assembled state in which the urging force is maintained. The temporary spring unit in the temporarily assembled state is attached to the retractor by fitting the tip end protruding portion of the spindle around which the webbing is wound in the winding direction into the fitting hole of the spring shaft.

[0008]

An embodiment will be described with reference to the drawings. FIG. 1 is a partial sectional front view of a mainspring spring unit of the seatbelt retractor according to the present invention at the time of temporary assembly (during storage), FIG. 2 is a side view, FIG. 3 is an exploded perspective view, and FIG. It is an exploded perspective view of a mainspring spring unit at the time. 5 is a front view of the casing 20, FIG. 6 is a sectional view taken along line AA of FIG. 5, FIG. 7 is a longitudinal sectional view of the spring shaft 30, and FIG .
You .

Reference numeral 10 denotes a mainspring for applying a desired winding force to a webbing (not shown). Spring spring 1
0 has an internal locking portion 11 at one end (inner end) and an external locking portion 12 at the other end (outer end). Spring spring 10
Is stored in the casing 20.

The casing 20 has a substantially circular bottom plate 21.
And a peripheral plate 22 erected from the peripheral edge of the bottom plate 21 and a flange 23 bent from the peripheral plate 22. In the center of the inner wall surface of the bottom plate 21, a through hole 2 having a step portion 24a is provided.
4 are provided. And the through hole 2 on the outer wall surface side of the bottom plate 21
A concave portion 25 is provided in the periphery of the ring 4 in an annular shape.

The peripheral side plate 22 of the casing 20 is provided with an engaging hole 26 for engaging with a plate 50 described later. Further, on the inner wall surface below the peripheral side plate 22, a spring 10 is provided.
A notch groove 27 for locking the external locking portion 12 is provided.
Further, a bent wall portion 22a is formed on an outer wall surface below the peripheral side plate 22 to lock a stopper 60 described later. A guide groove 28 for guiding the stopper 60 is provided continuously to the bent wall portion 22a. Flange 2
An attachment projection 29 for attaching the mainspring unit to a retractor (not shown) is provided on the inner wall surface of the projection 3.

The spring shaft 30 has a tubular body 31 and a flange 32 provided around the peripheral wall of the tubular body 31 on the base end 31a side. Base end 31a of tubular body 31 (spindle 40 side)
From above, a fitting hole 33 is formed in which the tip end protruding portion 41 of the spindle 40 of the retractor for winding and supporting the webbing is fitted. The fitting hole 33 is formed so as to have a rectangular cross section in view of the fact that the tip end protruding portion 41 of the spindle 40 has a square pole shape.

The distal end portion 31b of the tubular body 31 (casing 2)
A locking groove 34 for locking the internal locking portion 11 of the mainspring spring 10 is provided on the peripheral wall (0 side). A small-diameter cylindrical portion 35 rotatably engaged with and supported by the step portion 24a of the casing 20 is provided at the distal end portion 31b of the cylindrical body 31 so as to protrude therefrom. Further, an insertion hole 36 into which a stopper 60 described later is fitted is formed from the distal end portion 31b of the cylindrical body 31. The insertion hole 36 has a rectangular cross section and is formed coaxially with the fitting hole 33 so that the hole wall surfaces are parallel to each other. , 41 without confirmation.

The plate 50 closes the opening of the casing 20 and has substantially the same shape as the bottom plate 21 of the casing 20. At the center of the plate 50, the cylindrical body 3
An insertion hole 51 smaller than the outer diameter of the flange 32 of the spring shaft 30 is rotatably fitted with the base end 31a of the spring shaft 30. The periphery of the insertion hole 51 is provided with a spring shaft 3.
In order to receive the zero flange 32, a step 51a is provided on the inner wall surface side.

On the outer peripheral edge of the plate 50, a locking claw 52 which is engaged with the engaging hole 26 provided in the casing 20 is protruded. The plate 50 is attached to the casing 20 so as to close the opening with the mainspring 10 and the spring shaft 30 housed in the casing 20.

The stopper 60 is for retaining the biasing force of the mainspring 10 while holding it. At one end of the stopper 60, a floating portion 61 having a shape to be fitted to the concave portion 25 of the casing 20 is formed.
A shaft 62 that fits into the insertion hole 36 of the spring shaft 30 protrudes from the center of the floating portion 61. Shaft bar 62
Is formed so that the cross section thereof is rectangular so as to fit into the insertion hole 36.

At the other end of the stopper 60, an engaging piece 63 bent into an L-shaped cross section is formed to extend. This locking piece 6
3 engages with the guide groove 28 of the casing 20 and comes into contact with the bent wall portion 22a by the biasing force of the biased spring 10. When the rear wall of the stopper 60 is formed in a flat shape, stacking is possible when storing the spring units in the temporarily assembled state.

The stopper 60 can be attached by inserting a jig (not shown) into the fitting hole 33 of the spring shaft 30 and applying a biasing force to the mainspring 10, and moving the shaft 62 to the through hole 24 of the casing 20. And the insertion hole 36 of the spring shaft 30
Into the guide groove 28 of the casing 20.
And is brought into contact with the bent wall portion 22a. When the jig is removed in this state, the spring 10
With the urging force of the stopper 60, the state in which the locking piece 63 is engaged with the guide groove 28 and is in contact with the bent wall portion 22a is maintained, and the stopper 60
There is no risk of coming off. Thus, it is possible to provide a temporary spring unit in a temporarily assembled state in which the urging force in the webbing winding direction is applied.

When the webbing is pulled out and the spindle 40 is rotated while the mainspring spring unit is attached to the retractor, the stopper 60 can be easily removed by its own weight. After removing the stopper 60,
A cap 70 may be attached for appearance. The cap 70 has a circular shape so as to engage with the concave portion 25 of the casing 20.
What is necessary is just to form so that it may become flush with 1.

To assemble the mainspring spring unit according to the present invention, the mainspring spring 10 is housed in the casing 20, and the external locking portion 12 of the mainspring spring 10 is locked in the cut groove 27 of the casing 20. Next, the internal locking portion 11 of the mainspring 10 is locked in the locking groove 34 of the spring shaft 30. Then, the small-diameter cylindrical portion 35 of the spring shaft 30 is fitted to the step portion 24a of the casing 20.

Next, the base end 31a of the spring shaft 30 is fitted into the insertion hole 51 of the plate 50,
The plate 50 is attached so as to close the opening of the casing 20 by engaging the locking claws 52 of the casing 20 with the engaging holes 26 of the casing 20. At this time, the flange 32 of the spring shaft 30
Is rotatably fitted to the step portion 51a of the plate 50. As described above, before closing the opening of the casing 20 with the plate 50, the spring shaft 30 is connected to the mainspring 1.
Since the spring is locked to zero, the work of locking the spring shaft 30 to the mainspring spring 10 can be easily performed.

Thereafter, an appropriate jig is inserted into the fitting hole 33 of the spring shaft 30 to apply a biasing force in the webbing winding direction to the mainspring 10. With this urging force applied, the shaft 62 of the stopper 60 is inserted into the through hole 2 of the casing 20.
4 and the insertion hole 36 of the spring shaft 30. At this time, the floating portion 61 of the stopper 60 is engaged with the concave portion 25 of the casing 20. Then, the locking piece 63 of the stopper 60 is brought into contact with the bent wall portion 22a while being guided by the guide groove 28 of the casing 20.

When the jig is removed in the above state, the locking piece 63 of the stopper 60 is pressed against the bent wall portion 22a of the casing 20 by the urging force of the mainspring 10, and the spring is in a temporary assembled state in which the urging force is maintained. The unit is completed. The locking piece 63 of the stopper 60 is formed to be bent in an L-shaped cross section together with the urging force of the mainspring 10 and is engaged with the guide groove 28 of the casing 20.
Even if the mainspring spring unit is dropped, the stopper 60 does not come off. Then, both ends 31 of the spring shaft 30
Since a and 31b are supported by the plate 50 and the casing 20, respectively, they do not come off even if an impact is applied, and they can rotate in a stable state and are hardly worn.

In order to attach the spring unit in the temporarily assembled state to the retractor, the tip projecting portion 41 of the spindle 40 on which the webbing is wound in the winding direction is fitted into the fitting hole 33 of the spring shaft 30 and the casing is fitted. 20 is attached to the retractor. Fitting hole 3 in spring shaft 30
By providing the insertion hole 3 and the insertion hole 36, the engagement angle with the spindle 40 is constant, and the work of assembling the mainspring unit to the retractor becomes easy.

Then, the stopper 60 is removed. The stopper 60 can be easily removed by its own weight when the webbing is pulled against the urging force. Even if the cap 70 is used in appearance, the cap 70 can be attached to the casing 20 without contacting the spring shaft 30. Thus, a desired winding force is applied to the webbing.

[0026]

According to the present invention, the spring shaft is engaged with the mainspring before the opening of the casing is closed with the plate, so that the spring shaft can be easily engaged with the mainspring. be able to. Further, since both ends of the spring shaft are supported by the plate and the casing, the spring shaft does not come off even if an impact is applied, and can be rotated in a stable state and is hardly worn. Furthermore, even if an urging force is applied to the mainspring, the stopper is maintained in pressure contact with the bent wall portion of the casing, so that the stopper does not accidentally come off, and a spring unit that maintains the urging force can be provided.

[Brief description of the drawings]

FIG. 1 is a partial sectional front view of a mainspring spring unit of a seatbelt retractor according to the present invention at the time of temporary assembly (at the time of storage).

FIG. 2 is a side view of FIG.

FIG. 3 is an exploded perspective view of the spring unit of the seatbelt retractor according to the present invention at the time of temporary assembly (at the time of storage).

FIG. 4 is an exploded perspective view of the mainspring spring unit of the seatbelt retractor according to the present invention when attached.

FIG. 5 is a front view of a casing.

FIG. 6 is a sectional view taken along line AA of FIG. 5;

FIG. 7 is a longitudinal sectional view of a spring shaft.

FIG. 8 is a longitudinal sectional view of a plate.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Mainspring 20 Casing 21 Bottom plate 22 Peripheral side plate 22a Curved wall part 24 Through-hole 24a Step part 28 Guide groove 30 Spring shaft 31a Base end part 31b Tip part 32 Flange rim 33 Fitting hole 36 Insertion hole 40 Spindle 41 Tip projection part 50 Plate 51 Insertion hole 60 Stopper 62 Shaft bar 63 Locking piece

Claims (2)

(57) [Scope of request for utility model registration] 1. A casing in which one end of a mainspring is locked and accommodated and a through hole having a step is provided in the center of a bottom plate, and a tip end in which the other end of the mainspring is locked and an insertion hole is provided. A spring shaft rotatably engaged with the step portion, a fitting hole provided in the base end portion is fitted with a spindle tip for winding and supporting the webbing, and a flange edge is formed on the base end portion, The base end of the spring shaft is rotatably fitted in the center, and an insertion hole smaller than the outer diameter of the flange edge of the spring shaft is provided, and a plate that engages with the casing and closes the opening of the casing is provided. An outer wall of a peripheral side plate erected from a shaft rod fitted in the insertion hole and a peripheral edge of a bottom plate of the casing.
A stopper provided with a locking piece that comes into contact with a bent wall portion formed on the surface, and a shaft of the stopper is fitted into the through hole of the casing and the insertion hole of the spring shaft in a state where a biasing force is applied to the mainspring. Locking piece of casing on curved wall
By abutting the part, the seat belt retractor of the spiral spring unit, characterized in that so as to retain the biasing condition of the spiral spring. 2. A guide groove which is continuous with a bent wall portion of a casing is provided, and a locking piece having an L-shaped cross section formed at an end of a stopper is engaged with the guide groove and is brought into contact with the bent wall portion. The spring unit for a seat belt retractor according to claim 1, wherein