JPH0733963Y2 - Winding spring device for seat belt retractor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a winding spring device for a seat belt retractor.

[Conventional technology]

A seat belt retractor attached to the seat of a vehicle or the like has a return spring attached to a spindle that supports a winding drum around which the webbing is wound so that the webbing is automatically wound when an occupant releases the seat belt. Are connected.

By the way, the attachment of the return spring requires applying a biasing force to the spring in order to wind up and store the webbing. Therefore, conventionally, after assembling the return spring and the spindle, the spring cover or the spindle is rotated to a predetermined position. The webbing was then wound around a take-up drum and then assembled. However, such a mounting method has a problem that the work is difficult and the efficiency is low.

To solve this problem, in the past
-119667 is provided. This is a bottomed spring cover that locks and stores one end of the return spring, and a fitting that inserts from the open end of this spring cover to lock the other end of the return spring and fit the tip of the spindle. A seatbelt retractor take-up spring device including a tubular bush having a hole, wherein at least two engaging grooves are provided in a tubular peripheral portion of the bush, and a circular plate is formed on a bottom plate of the spring cover. The insertion hole and a plurality of cutouts are provided on the peripheral surface of the insertion hole, while at least two engagement projections that engage with the engagement grooves of the bush and the cutouts of the spring cover are provided on one end surface of the plate-shaped portion. Is provided with a locking member having a plurality of engaging pieces engageable with the return spring, and the bush is locked to the return spring to apply a biasing force to the return spring. The engaging member is inserted into the circular insertion hole of the spring cover, the engaging projection of the engaging member is engaged with the engaging groove of the bush, and the engaging piece is formed in the notch provided in the circular insertion hole. It is configured so as to be engaged with the inner wall surface of the part.

[Problems to be solved by the device]

In the one described in the above publication, since there is no guarantee that the center of the bush is aligned with the center of the spring cover, it is difficult to engage the locking member with the bush, and a special jig is required for the engaging work. It has drawbacks. Further, there is a drawback that the locking member is removed after the winding spring device is attached to the retractor body, but a special cap for closing the opening of the spring cover after removing the locking member must be attached. . Further, due to the shape of the locking member and the cap to be attached thereafter, dust easily enters through the gap between the peripheral portion of the circular insertion hole or cutout and the plate-shaped portion of the locking member or cap, and It also has the drawback of being prone to rust and failure.

The present invention has been made in view of the above problems of the conventional technology, and an object of the present invention is to provide a seat belt retractor that is easy to assemble and is suitable for mass production and automatic assembly. It is intended to provide a winding spring device.

[Means for Solving the Problems]

In order to achieve the above object, a seat belt retractor take-up spring device according to the present invention includes a spring cover that locks one end of a return spring and accommodates the return spring, and a spring cover that is fitted to a central portion of the return spring. A winding spring device for a seat belt retractor, comprising: a tip of a spindle that holds the other end of a spring and supports a winding drum around which a webbing is wound; and a bush having a fitting hole that fits in the spring cover. A receiving cylinder provided in the center of the bottom plate, a bottomed sleeve having a central hole having a large diameter portion and a small diameter portion formed in the bush so as to be rotatably fitted in the receiving cylinder, and the receiving sleeve. A through hole of a cylinder and a locking member having a shaft rod fitted in a small diameter portion of the central hole of the bottomed sleeve, and the return spring by locking the bush to the return spring. And characterized in that fitting the shaft rod of the locking member in a state that gave a biasing force to ring the center hole diameter of the through hole and the bushing of the spring cover.

Further, the through-hole of the receiving cylinder and the small-diameter portion of the central hole of the bottomed sleeve have a polygonal or elliptical cross section, and the shaft of the locking member is used as the through-hole of the receiving cylinder and the small-diameter portion of the central hole of the bottomed sleeve. It has the same shape as.

Furthermore, an annular cut groove is provided in the center of this shaft rod so that the shaft rod of the locking member can be cut after the tip of the spindle is fitted into the bush and the spring cover is attached to the retractor body. It is characterized in that the member is a cap inserted into the through hole of the spring cover.

〔Example〕

 Examples will be described with reference to the drawings.

FIG. 1 is an exploded perspective view of a main part of a seat belt retractor take-up spring device according to the present invention, and FIG. 2 is a retractor body 70.
Sectional view of the winding spring device before being attached to the
The drawing is a vertical cross-sectional view of a state in which the winding spring device is attached to the retractor body 70.

10 is a return spring, one end of which has an internal locking piece
11 and an external locking piece 12 at the other end.

Reference numeral 20 is a spring cover that houses the return spring 10. The spring cover 20 has a substantially circular bottom plate 21.
And a peripheral side edge 22 erected from the peripheral edge of the bottom plate 21, and a flange 23 bent from the peripheral side edge 22. At the center of the inner wall surface of the bottom plate 21, a cylindrical receiving cylinder 24 is provided so as to project. A through hole 25 penetrating to the bottom plate 21 is provided at the center of the receiving cylinder 24, and the through hole 25 is formed to have a polygonal cross section or an elliptical cross section. Then, the bottom plate 21 of this through hole 25
An annular groove 26 is provided in the vicinity. A step portion 27 is provided on the outer wall surface of the bottom plate 21 at the peripheral edge portion of the through hole 25. Further, the flange 23 is provided with engagement receiving portions 28, 28 that engage with a plate 50 described later. Although not shown, the bottom plate 21
A locking portion for locking the external locking piece 12 of the return spring 10 is provided on the inner wall surface of the.

Reference numeral 30 denotes a bush having a cylindrical shape, and a brim 31 is provided around the center portion. Spring cover from flange 31 of bush 30
A bottomed sleeve 32 is rotatably fitted on the receiving sleeve 24 of the spring cover 20 on the 20 side. This bottomed sleeve 32
The central hole 33 has a large diameter portion 33a having an inner diameter slightly larger than the outer diameter of the receiving cylinder 24 provided on the opening side, and a small diameter portion 33b having a polygonal cross section or an elliptical shape provided in the inner depth portion. . Further, the bottomed sleeve 32 is provided with locking grooves 34, 34 for locking the internal locking piece 11 of the return spring 10. On the other hand, on the spindle 40 side from the flange 31 of the bush 30, a bottomed cylinder 35 into which the tip protruding portion 41 of the spindle 40 is fitted is provided to project. The fitting hole 36 of the bottomed cylinder 35 is formed so as to have a quadrangular cross section in view of the tip end protruding portion 41 of the spindle 40 having a quadrangular prism shape.

The plate 50 has substantially the same shape as the bottom plate 21 of the spring cover 20, and an insertion hole 51 for inserting the bottomed cylinder 35 of the bush 30 is formed in the center of the plate 50. This insertion hole 51 is provided with a step portion 51a on the inner wall surface side in order to receive the flange 31 of the bush 30. Engaging claw pieces 52, 52 that engage with the engaging receiving portions 28, 28 provided on the flange 23 are projectingly provided on the outer peripheral edge portion of the plate 50, and the plate 50 is provided in the spring cover 20 with a return spring 10. And the bush 30 are stored, the spring cover 20
It can be attached to.

Reference numeral 60 denotes a locking member for locking the return spring 10 in a state where the biasing force of the return spring 10 is maintained. Locking member 60
Is a grip plate 61 having a shape that fits with the step portion 27 provided on the bottom plate 21 of the spring cover 20, and the through hole 25 of the receiving cylinder 24 and the bottomed sleeve 32 at the center of the grip plate 61. Center hole small diameter part
It has a shaft rod 62 protruding so as to be fitted in 33b. The shaft rod 62 is
An annular protrusion 63 is provided around the base end of the shaft 62, and an annular cut groove 64 is provided in the center of the shaft rod 62 so that the tip end of the shaft rod 62 can be cut. Then, by inserting the spindle 40 tip projection 41 into the fitting hole 36 of the bottomed cylinder 35 of the bush 30 and attaching the spring cover 20 to the retractor body 70, the shaft rod 62 is cut by the annular cut groove 64. , The through hole of the spring cover 20 using the locking member 60 as a cap
Can be attached to 25. At this time, the annular projection 63 of the shaft rod 62 fits into the annular groove 26 of the through hole 25, and there is no risk that the locking member 60 will come off from the spring cover 20. Furthermore, the shaft rod
The central portion and the tip portion of 62 are formed to have a polygonal or elliptical cross section so as to fit with the through hole 25 of the spring cover 20 and the small diameter portion 33b of the bottomed sleeve 32 of the bush 30. There is. The locking member 60 locks the bush 30 to the return spring 10 and applies the biasing force to the return spring 10 to move the shaft rod 62 into the through hole 25 of the spring cover 20 and the bush 30. It is fitted into the small diameter portion 33b of the central hole.

The winding spring device is attached to the side plate 71 of the retractor body 70. Reference numeral 72 is a winding drum that is mounted on the outer periphery of the spindle 40 and is supported by the spindle 40 to wind the webbing 73.

[Action]

To assemble the winding spring device according to the present invention, the return spring 10 is housed in the spring cover 20, and the external locking piece 12 of the return spring 10 is attached to the spring cover.
Hang it on the not-shown locking part in 20. Next, the receiving cylinder 24 of the spring cover 20 and the central hole large diameter portion 33a of the bottomed sleeve 32 of the bush 30 are fitted to each other, and the internal locking piece 11 of the return spring 10 is fitted to the bottomed sleeve 32 of the bush 30. It is locked in the locking groove 34 of. Next, the engagement receiving portions 28, 28 of the spring cover 20 are engaged with the engagement claw pieces 52, 52 of the plate 50 to attach the plate 50 so as to close the opening of the spring cover 20.

After that, a proper jig is inserted into the fitting hole 36 of the bush 30 to apply a biasing force to the return spring 10 in the webbing winding direction. In this state, hold the grip plate 61 of the locking member 60 and insert the shaft rod 62 into the through hole 25 of the spring cover 20 and the bush 30.
It is fitted into the central hole small diameter portion 33b of the bottomed sleeve 32. At this time, the receiving tube 24 of the spring cover 20 and the central hole large diameter portion 33a of the bottomed sleeve 32 of the bush 30 are fitted together, and both holes 25,
Since 33b match, the shaft rod 62 of the locking member 60 can be easily fitted.

When the jig used for rotating the bush 30 in the above state is removed, the through hole 25 of the receiving cylinder 24 and the central hole small diameter portion 33b of the bottomed sleeve 32 are made into a polygonal or elliptical cross section, and Since the shaft rod 62 of the stop member 60 has the same shape, the stop member 60
Will not fit into the holes 25 and 33b of both members and will not rotate, and the biasing force of the return spring 10 will be retained. This state is shown in FIG.

In this state, the tip end protruding portion 41 of the spindle 40 around which the webbing 73 is wound in the winding direction is fitted into the fitting hole 36 of the bush 30, and the spring cover 20 is attached to the side plate 11 of the retractor body 70. Thereafter, the locking member 60 is pulled out, the shaft rod 62 is cut along the annular cut groove 64, and the locking member 60 is inserted into the through hole 25 of the spring cover 20 as a cap. In this way, the webbing 73 is given a desired winding force.

[Effect of device]

The present invention is configured as described above, and the receiving cylinder of the spring cover and the large diameter portion of the central hole of the bushing with a bottom of the bush are fitted together, and since both holes are aligned, locking is achieved. This has the effect that the members can be easily inserted and removed.

Further, the locking member can be used also as a cap, which is efficient.

Furthermore, the spring cover is provided with a receiving cylinder, and the fitting between this receiving cylinder and the bush has a labyrinth structure in the vertical section, which makes it difficult for dust to enter and the return spring is rusty. It also has the effect of making it less likely that equipment failure will occur.

Furthermore, this device has an effect that it is easy to assemble and is suitable for mass production and automatic assembly.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a main part of a winding spring device for a seat belt retractor according to the present invention, FIG. 2 is a longitudinal sectional view of the winding spring device before being attached to a retractor body, and FIG. It is a longitudinal cross-sectional view of a state where the spring collecting device is attached to the retractor body. 10 …… Return spring, 20 …… Spring cover,
21 …… Bottom plate, 24 …… Receptacle, 25 …… Through hole, 30 …… Bush, 32 …… Bottom sleeve, 33 …… Central hole, 33a …… Large diameter part, 3
3b …… Small diameter part, 36 …… Mating hole, 40 …… Spindle, 41…
… Tip protrusion, 50 …… Plate, 60 …… Locking member, 62…
… Shaft, 64 …… Annular kerf, 70 …… Retractor body, 72…
… Winding drum, 73… Webbing.

Claims (3)

[Scope of utility model registration request] 1. A spring cover for locking one end of a return spring to be housed therein, and a winding drum fitted on the center of the spring cover for locking the other end of the return spring and winding a webbing. In a retracting spring device for a seat belt retractor having a supporting spindle tip and a bush having a fitting hole, a receiving cylinder provided at the center of the bottom plate of the spring cover and rotatable to the receiving cylinder. And a bottomed sleeve provided with a central hole having a large diameter portion and a small diameter portion formed in the bush to be fitted into the bush, and a through hole of the receiving sleeve and a small diameter portion of the central hole of the bottomed sleeve. A lock member having a shaft rod, and the bush of the return spring is locked to apply a biasing force to the return spring to lock the shaft of the lock member to the spring cover. Device the winding spring of the retractor, characterized in that to fit into the central hole diameter of the through hole and the bushing. 2. The through hole of the receiving cylinder and the central hole small diameter portion of the bottomed sleeve have a polygonal or elliptical cross section, and the shaft of the locking member is the center of the through hole of the receiving sleeve and the center of the bottomed sleeve. The winding spring device for a seat belt retractor according to claim 1, wherein the winding spring device has the same shape as the small diameter portion. 3. An annular kerf is provided at the center of the shaft rod so that the shaft rod of the locking member can be cut after the tip of the spindle is fitted into the bush and the spring cover is attached to the retractor body. The winding spring device for a seat belt retractor according to claim 1 or 2, wherein the locking member is a cap that is inserted into and inserted into the through hole of the spring cover.