JP2003252172A - Webbing take-up device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a webbing take-up device capable of properly tightening a webbing and properly controlling the load to an occupant by the webbing. <P>SOLUTION: In this webbing take-up device 10, a retainer 54 is moved with a piston 34 to keep a state that a gas-vent hole 44 is closed by the retainer 54, when the piston 34 is raised by a pretensioner mechanism 18. Whereby the piston 34 is raised with high pressure and the webbing can be properly tightened. On the other hand, when the piston 34 is lowered by a force limiter mechanism, the retainer 54 is pressed by the piston 34, whereby the retainer 54 is rotated, the gas-vent hole 44 is opened, and a packing 50 is removed from the gas-vent hole 44 by the pressure of a gas at a lower side of an engagement part 36. Whereby the lowering of the piston 34 can be prevented from being disturbed by the gas at the lower side of the engagement part 36, and the load to the occupant by the webbing can be properly controlled. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a webbing retractor having a so-called pretensioner mechanism and a force limiter mechanism.

[0002]

2. Description of the Related Art A webbing retractor is disclosed, for example, in Japanese Patent Laid-Open No.
As described in one embodiment of JP-A-0-67300, a winding shaft is provided, and a webbing is wound around the winding shaft.

This webbing retractor is a so-called rack & rack.
It is equipped with a pinion type pretensioner mechanism. The pretensioner mechanism includes a pinion, and the pinion is connected to the winding shaft and always rotates integrally with the winding shaft. A cylindrical cylinder is provided near the pinion, and gas is supplied to one side of the cylinder in an emergency of the vehicle.

A piston is movably provided in the cylinder, and a fitting portion is provided at one end of the piston. The fitting portion is substantially fitted to the inner surface of the cylinder. In an emergency of the vehicle, the piston receives the pressure of the gas from one side of the fitting portion and moves inside the cylinder toward the other side. Further, a rack is provided on the other side of the piston, and when the piston is moved to the other side, the rack meshes with the pinion to rotate the pinion in the webbing winding direction. As a result, the webbing is wound around the winding shaft, and the looseness of the webbing is removed.

Further, this webbing retractor is provided with a force limiter mechanism. The force limiter mechanism includes, for example, an energy absorbing member, and when the load of the occupant on the webbing exceeds a predetermined amount in an emergency of the vehicle, the energy absorbing member is deformed so that the webbing pull-out direction is increased. The winding shaft is allowed to rotate. As a result, the webbing is pulled out from the winding shaft, and the load of the webbing on the occupant is limited to a predetermined amount or less.

Further, when the force limiter mechanism operates, the winding shaft is rotated in the webbing pull-out direction.
Along with this, the pinion is rotated in the webbing pull-out direction, and the piston is moved in the cylinder toward one side.

In this webbing retractor, the piston has a gas vent hole, and the gas vent hole communicates one side and the other side of the fitting portion. As a result, when the force limiter mechanism operates and the piston moves toward one side in the cylinder, gas is discharged from one side of the fitting portion to the other side through the gas vent hole, The gas in the cylinder (on the one side of the fitting portion) is prevented from hindering the movement of the piston toward the one side, and the hindrance of the webbing from the winding shaft is suppressed.

However, in such a webbing retractor, if the gas vent hole is large, a large amount of gas flows from one side of the fitting portion to the other side through the gas vent hole when the pretensioner mechanism is activated. There is a problem that the piston cannot be moved to the other side with a high pressure after being discharged.

On the other hand, if the gas vent hole is small, the amount of gas discharged from one side of the fitting part to the other side through the gas vent hole is reduced when the force limiter mechanism operates, and the fitting part There is a problem that the inhibition of the movement of the piston to one side by the gas on one side cannot be sufficiently suppressed.

Furthermore, the webbing take-up device described in another embodiment of Japanese Patent Application Laid-Open No. 10-67300 is provided with a packing, and the packing is a gas when fitted between the cylinder and the rack. The vent hole is closed.

Here, the packing is in contact with the other side surface of the fitting portion. Therefore, when the piston is moved to the other side by the pretensioner mechanism, the packing is moved together with the piston, so that the packing is moved. Keeps the gas vent hole closed, and suppresses the discharge of gas from one side of the fitting portion to the other side.

Furthermore, the sliding resistance between the packing and the cylinder is made larger than the sliding resistance between the packing and the rack. Therefore, when the piston is moved to one side by the force limiter mechanism, The moving speed of the packing is made slower than the moving speed of the piston to open the gas vent hole, whereby the gas is discharged from one side of the fitting portion to the other side.

However, in such a webbing retractor, the packing is made of rubber. For this reason,
When the pretensioner mechanism operates, there is a problem that the packing is deformed due to the pressure of gas or the like, and the gas vent hole cannot be reliably closed.

Furthermore, due to molding errors such as packing,
It is difficult to set the sliding resistance between the packing and the cylinder larger than the sliding resistance between the packing and the rack. Therefore, when the force limiter mechanism operates,
There is also a problem that the moving speed of the packing cannot be made slower than the moving speed of the piston and the gas vent hole cannot be surely opened.

[0015]

In consideration of the above facts, the present invention can satisfactorily remove the looseness of the webbing when the pretensioner mechanism operates, and at the same time, reduces the load on the occupant by the webbing when the force limiter mechanism operates. It is an object to obtain a webbing retractor that can be favorably restricted.

[0016]

According to another aspect of the present invention, there is provided a webbing take-up device including a take-up shaft for taking up a webbing, a cylindrical accommodating member, a cylindrical accommodating member, and the accommodating member. A moving member provided with a fitting portion substantially fitted to the inner surface thereof, and supplying the gas to the fitting portion one side in the housing member at the time of an emergency of the vehicle, thereby moving the moving member A pretensioner mechanism that rotates the take-up shaft in a direction in which the webbing is taken up by moving the webbing to the other side by pressure, and the webbing when the occupant's load on the webbing exceeds a predetermined amount in an emergency of the vehicle. A webbing retractor including a force limiter mechanism that permits rotation of the winding shaft in a pull-out direction to move the moving member to one side, the webbing winding device being provided on the moving member,
A gas vent hole that communicates one side and the other side of the fitting part, and the other side of the fitting part that is provided on the other side of the fitting part in a state where the gas vent hole is closed. The moving member is moved together with the moving member to keep the gas vent hole closed, and the moving member is moved to one side by the force limiter mechanism. And a closing member which is rotated by pressing the moving member side portion to open the gas vent hole.

In the webbing retractor according to the first aspect of the present invention, the webbing retractor is provided with a pretensioner mechanism, and gas is supplied to the inside of the housing member (one side of the fitting portion of the moving member) in an emergency of the vehicle, thereby The moving member is moved to the other side by the pressure, and the winding shaft is rotated in the direction for winding the webbing. As a result, the webbing is wound around the winding shaft, and the looseness of the webbing is removed.

Further, the webbing retractor according to claim 1 is provided with a force limiter mechanism, and in the emergency of the vehicle, when the load of the occupant on the webbing exceeds a predetermined amount, the direction of pulling out the webbing is provided. The rotation of the take-up shaft is permitted. As a result, the webbing is pulled out from the winding shaft, and the load of the webbing on the occupant is limited to a predetermined amount or less. Further, at this time, the moving member is moved to one side by rotating the winding shaft in the direction of pulling out the webbing.

By the way, the moving member is provided with a gas vent hole, and the gas vent hole connects one side and the other side of the fitting portion. Further, a closing member is provided on the other side of the fitting portion, and the closing member closes the gas vent hole.

Here, when the moving member is moved to the other side by the pretensioner mechanism, the closing member is moved together with the moving member, so that the closing member keeps the gas vent hole closed. This can prevent a large amount of gas from being discharged from one side of the fitting part to the other side, and the piston can be moved with a high pressure to satisfactorily remove the looseness of the webbing.

Further, when the moving member is moved to one side by the force limiter mechanism, the closing member presses the moving member side portion to the moving member through which the load of the occupant on the webbing is transmitted through the winding shaft. By doing so, the closing member is rotated and the gas vent hole can be surely opened. As a result, the amount of gas discharged from one side of the fitting part to the other side is increased, and the obstruction of the movement of the piston due to the gas on one side of the fitting part can be sufficiently suppressed, and the occupant due to the webbing can be prevented. The load can be well limited.

Further, as described above, when the moving member is moved to one side by the force limiter mechanism, the closing member is rotated and the gas vent hole is opened, so that, for example, friction between the closing member and the inner surface of the accommodating member. It is not always necessary to open the gas vent hole by increasing the force to make the moving speed of the closing member smaller than the moving speed of the moving member, and thereby the inner surface of the containing member is damaged (damaged, etc.) by the closing member.
Can be suppressed.

The webbing retractor according to claim 2 is
The webbing retractor according to claim 1, wherein a portion of the closing member on the side opposite to the moving member is in contact with an inner surface of the housing member.

In the webbing retractor according to the second aspect of the invention, the portion of the closing member on the side opposite to the moving member is in contact with the inner surface of the containing member. Therefore, when the moving member is moved to the other side by the pretensioner mechanism and the closing member is moved together with the moving member, it is possible to prevent the closing member from being displaced from between the moving member and the accommodation member inner surface. The state in which the closing member closes the gas vent hole can be favorably maintained.

Further, therefore, when the moving member is moved to one side by the force limiter mechanism and the moving member presses the moving member side portion, the closing member is rubbed by the frictional force between the closing member and the inner surface of the containing member. Can be reliably rotated, and thereby the gas vent hole can be opened more reliably.

Further, when the closing member is made of metal or the like and has a high rigidity, it is possible to prevent the closing member from being deformed by the pressure of the gas when the pretensioner mechanism is activated. The member can reliably close the gas vent hole.

The webbing retractor according to claim 3 is
The webbing take-up device according to claim 1 or 2, wherein the gas vent hole is provided in a hermetically sealed manner, and when the moving member is moved to the other side by the pretensioner mechanism, the moving member and the blocking member are closed. By keeping the gas vent hole closed by being moved together with the member, the closing member opens the gas vent hole when the moving member is moved to one side by the force limiter mechanism. It is characterized by comprising a sealing member for releasing the sealing of the gas vent hole.

In the webbing retractor according to the third aspect, when the moving member is moved to the other side by the pretensioner mechanism, the closing member is moved together with the moving member and the closing member, so that the closing member is gas. The closed state of the vent hole is maintained. As a result, a large amount of gas can be prevented from being discharged from one side of the fitting portion to the other side, and the looseness of the webbing can be removed more favorably.

Further, when the moving member is moved to one side by the force limiter mechanism, the closing member opens the gas vent hole, so that the sealing member releases the sealing of the gas vent hole. As a result, the amount of gas discharged from one side of the fitting portion to the other side can be increased, and the load of the webbing on the occupant can be favorably limited.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 3 is a side view showing a schematic structure of a webbing retractor 10 according to an embodiment of the present invention.

The webbing retractor 10 includes a frame 12
The frame 12 is fixed to the vehicle.
A winding shaft 14 is rotatably supported by the frame 12, and a webbing 16 is wound around the winding shaft 14.

The webbing take-up device 10 is provided with a rack and pinion type pretensioner mechanism 18, and a pinion 20 is connected to one end of the take-up shaft 14. The pinion 20 always rotates integrally with the winding shaft 14, whereby the webbing 16 is wound or pulled out.

A base cartridge 22 as a housing member is fixed to the frame 12. The base cartridge 22 is formed in a cylindrical shape, and an upper end side (other side) of the base cartridge 22 opens near the pinion 20 and a lower end side (one side) of the base cartridge 22 is closed.

A gas supply hole 24 is formed at the lower end of the base cartridge 22, and the gas supply hole 24 penetrates the base cartridge 22. Further, a gas generating cylinder 26 is integrally formed at the lower end of the base cartridge 22, and the inside of one end side of the gas generating cylinder 26 has a gas supply hole 24.
Is in communication with.

A gas generating agent 28 such as MGG (micro gas generator) is housed in the gas generating tube 26, and the gas generating agent 28 is disposed on the outside of the gas generating tube 26. It is integrated with 30. A cap 32 having a bottomed cylindrical shape is fixed to the other end of the gas generating cylinder 26, and a closing lid 30 is accommodated in the cap 32. The bottom wall of the cap 32 covers the closing lid 30 with the gas generating cylinder 26.
The gas generating cylinder 26 is pushed to the side and is closed by the closing lid 30.
The other end of is closed. Here, in an emergency of the vehicle due to a collision or the like, the gas generated in the gas generating cylinder 26 by the gas generating agent 28 (for example, ignition of MGG) is supplied from the gas supply hole 24 into the base cartridge 22.

A piston 34 as a moving member is provided in the base cartridge 22.
Is vertically movable in the base cartridge 22. A disc-shaped fitting portion 36 is formed near the lower end of the piston 34, and the fitting portion 36 is substantially fitted to the inner surface of the base cartridge 22. The gas supply hole 24
Is arranged below the fitting portion 36, and when gas is supplied into the base cartridge 22, the pressure of this gas moves the piston 34 in the direction of arrow A (the other side) in FIG. ) Do.

The lower end of the piston 34 (the portion directly below the fitting portion 36) is cylindrical, and an O-ring 38 is fitted around the lower end of the piston 34. The O-ring 38 has elasticity and is in close contact with the inner surface of the base cartridge 22, so that the gas on the lower side of the fitting portion 36 is above the fitting portion 36 from between the fitting portion 36 and the inner surface of the base cartridge 22. The O-ring 38 prevents the escape.

A portion of the piston 34 above the fitting portion 36 is formed into a substantially rectangular column shape, and a rack 40 is formed on the rear side wall of the piston 34 from the upper end portion to the middle portion. The rack 40 corresponds to the above pinion 20,
When the piston 34 moves in the direction of arrow A in FIG. 3, the rack 40 meshes with the pinion 20. As a result, the take-up shaft 14 is rotated in the direction of arrow B in FIG. 3 (the direction in which the webbing 16 is taken up) via the pinion 20, and the webbing 16 is taken up by the take-up shaft 14.

Further, the webbing retractor 10 is provided with a force limiter mechanism (not shown), and the force limiter mechanism has an energy absorbing member (not shown). When the occupant's load on the webbing 16 exceeds a predetermined amount in an emergency of the vehicle, the energy absorbing member is deformed by the occupant's load on the webbing 16, and
The winding shaft 14 is allowed to rotate in the direction of arrow D (the direction in which the webbing 16 is pulled out). As a result, the webbing 16 is pulled out from the winding shaft 14, and the piston 34 is moved (lowered) in the direction of arrow C (one side) in FIG. 3 via the pinion 20 and the rack 40.

As shown in FIGS. 5A and 5B, a rectangular parallelepiped fitting recess 42 is formed on the right side wall of the lower portion of the piston 34, and the lower surface of the fitting recess 42 has the fitting portion 36. It is formed by the upper surface.

A gas vent hole 44 is formed in the lower portion of the piston 34, and the gas vent hole 44 is L-shaped and has a vertical hole 46 and a horizontal hole 48. One end of the gas vent hole 44 (the right end of the horizontal hole 48) is opened in the fitting recess 42, and the other end of the gas vent hole 44 (the lower end of the vertical hole 46) is opened in the lower surface of the piston 34. The hole 44 communicates the upper side and the lower side of the fitting portion 36. As a result, the gas on the lower side of the fitting portion 36 can be discharged to the upper side of the fitting portion 36 via the gas vent hole 44. In addition, in the gas vent hole 44, a spherical (or cylindrical) packing 50 as a sealing member is provided near one end.
(See FIG. 1) is fitted, and the packing 50 is made of, for example, rubber and has elasticity to seal the gas vent hole 44.

An L-shaped gas discharge hole 52 is formed in the lower portion of the piston 34. One end of the gas discharge hole 52 is opened on the right side surface of the piston 34 above the fitting recess 42, and the gas discharge hole 52 is formed. The other end of is connected to the upper end of the vertical hole 46. As a result, the gas discharge hole 52 communicates the upper side and the lower side of the fitting portion 36 via the vertical hole 46, and the gas below the fitting portion 36 passes through the vertical hole 46 and the gas discharge hole 52. And is discharged to the upper side of the fitting portion 36.

As shown in FIG. 4, the base cartridge 22
Inside, a retainer 54 made of metal (stainless steel in the present embodiment) as a closing member shown in detail in FIG. 6 is provided, and the retainer 54 is formed by bending a substantially rectangular plate-shaped material. It has an annular shape. Retainer 5
The left side portion of the lower surface of 4 is a horizontal surface, and the retainer 54
Is placed on the fitting portion 36 in a state where the left side surface of the lower surface is in surface contact with the fitting portion 36 of the piston 34 (see FIG. 1). Curved protrusions 56 are formed at the right end of the retainer 54 on both front and rear sides, and each curved protrusion 56 is in contact with the inner surface of the base cartridge 22.

At the left end of the retainer 54, rectangular insertion notches 58 are formed on both front and rear sides of one end of the plate-shaped material, and L-shaped insertion protrusions 60 project upward on both front and rear sides of the other end of the plate-shaped material. The base end portion of each insertion protrusion 60 is inserted into each insertion notch 58. A square fitting protrusion 62 is provided at the tip of each insertion protrusion 60.
Are formed, and each fitting protrusion 62 projects upward from the tip of each insertion protrusion 60.

The left surface of the retainer 54 (one end of the plate-shaped material,
The left surface of each insertion projection 60 and each fitting projection 62 is a vertical surface, and the retainer 54 has the piston 34 at the left surface.
Is in surface contact with the fitting recess 42. Further, the upper edge of each insertion projection 60 is brought into contact with the upper surface of the fitting recess 42 (see FIG. 1), and the portion directly above the fitting recess 42 of the piston 34 is arranged between the fitting projections 62. There is. As a result, the retainer 54 closes the one end opening of the gas vent hole 44 on the left surface.

Here, as shown in FIG. 1, when the pretensioner mechanism 18 moves the piston 34 in the direction of arrow A, the lower left side portion of the retainer 54 is located on the left side of the piston 34.
When the retainer 54 is pressed by the fitting portion 36 of the
By being moved together, the state where the left surface of the retainer 54 closes the one end opening of the gas vent hole 44 and the state where the packing 50 seals the gas vent hole 44 are maintained.

On the other hand, as shown in FIG. 2, when the piston 34 is moved in the direction of arrow C by the force limiter mechanism, the load of the occupant on the webbing 16 is transmitted through the winding shaft 14 and the pinion 20. The upper edge of each insertion projection 60 (piston 34 side portion) of the retainer 54 is pressed against the upper surface of the fitting recess 42 of the piston 34, and each curved projection 56 (reverse piston 34 side portion) of the retainer 54 and the base cartridge 22. By generating frictional force with the inner surface,
The retainer 54 is rotated to open the one end opening of the gas vent hole 44, and the packing 50 is discharged from the gas vent hole 44 toward the fitting recess 42 by the pressure of the gas below the fitting portion 36. This is a configuration in which the sealing of the gas vent hole 44 by the packing 50 is released.

Next, the operation of this embodiment will be described.

The webbing retractor 10 having the above-described structure is equipped with the pretensioner mechanism 18, and the gas generated in the gas generating cylinder 26 by the gas generating agent 28 in an emergency of the vehicle is supplied from the gas supply hole 24 to the base cartridge. 22
By supplying to the inside (below the fitting portion 36 of the piston 34), the piston 34 is moved upward (in the direction of arrow A in FIGS. 1 and 3) by the pressure of the gas, and is wound via the pinion 20. The direction in which the webbing 16 is wound around the shaft 14 (see FIG.
In the direction of arrow B). As a result, the winding shaft 1
The webbing 16 is wound around the webbing 4, and the looseness of the webbing 16 is removed.

Further, the webbing retractor 10 is provided with a force limiter mechanism, and when the load on the webbing 16 exceeds a predetermined amount in an emergency of the vehicle, the load on the webbing 16 depends on the load on the webbing 16. The deformation of the energy absorbing member allows the winding shaft 14 to rotate in the direction in which the webbing 16 is pulled out (the direction of arrow D in FIG. 3). Thereby, the winding shaft 14 and the webbing 16
Is pulled out, and the load on the occupant by the webbing 16 is limited to a predetermined amount or less. At this time, the webbing 16
By rotating the take-up shaft 14 in the direction of pulling out, the piston 34 is moved downward (in the direction of arrow C in FIGS. 1 and 3) via the pinion 20.

By the way, the piston 34 has a gas vent hole 4
4 is provided, and the gas vent hole 44 connects the lower side and the upper side of the fitting portion 36. Further, a retainer 54 is provided above the fitting portion 36, and the retainer 54 closes the gas vent hole 44.

Here, when the piston 34 is moved upward by the pretensioner mechanism 18, the retainer 54 is moved together with the piston 34 so that the retainer 54 keeps the gas vent hole 44 closed. . As a result, a large amount of gas can be suppressed from being discharged from the lower side to the upper side of the fitting portion 36, and the piston 34 can be raised with a high pressure to satisfactorily remove the looseness of the webbing 16. At this time, the gas on the lower side of the fitting portion 36 is passed through the vertical hole 46.
By discharging the gas to the upper side of the fitting portion 36 through the gas discharge hole 52 and the gas discharge hole 52, the pressure on the piston 34, and thus the piston 34.
The rising power of is adjusted.

Furthermore, when the piston 34 is moved upward by the pretensioner mechanism 18, the packing 50 is moved together with the piston 34 and the retainer 54.
The state in which the packing 50 seals the gas vent hole 44 is maintained. Thereby, a large amount of gas can be prevented from being discharged from the lower side to the upper side of the fitting portion 36, and the looseness of the webbing 16 can be removed more favorably.

Since the curved projections 56 of the retainer 54 are in contact with the inner surface of the base cartridge 22, when the piston 34 is moved upward by the pretensioner mechanism 18 and the retainer 54 is moved together with the piston 34, It is possible to prevent the retainer 54 from shifting between the fitting recess 42 of the piston 34 and the inner surface of the base cartridge 22. As a result, the state in which the retainer 54 closes the gas vent hole 44 can be favorably maintained.

Further, since the retainer 54 is made of metal and has a high rigidity, it is possible to prevent the retainer 54 from being deformed due to the pressure of gas when the pretensioner mechanism 18 is operated. 54 can surely close the gas vent hole 44.

On the other hand, when the piston 34 is moved downward by the force limiter mechanism, the load of the occupant on the webbing 16 is transmitted to the fitting recess 42 of the piston 34, which is transmitted through the winding shaft 14 and the pinion 20. When the retainer 54 presses the upper edge of each insertion projection 60, the retainer 54 is rotated to surely open the one end opening of the gas vent hole 44, and the packing 50 is pressed by the pressure of the gas below the fitting portion 36. Is discharged from the gas vent hole 44, and the packing 50
The sealing of the gas vent hole 44 due to is released. As a result, the amount of gas discharged from the lower side to the upper side of the fitting portion 36 increases, and the lowering of the piston 34 due to the gas below the fitting portion 36 can be sufficiently suppressed, and the webbing 1
The load on the occupant due to 6 can be favorably limited.

Moreover, since the gas below the fitting portion 36 is discharged to the upper side of the fitting portion 36 through the vertical hole 46 and the gas discharge hole 52, it is discharged to the upper side from the lower side of the fitting portion 36. The amount of gas generated can be further increased, and the load applied to the occupant by the webbing 16 can be better limited.

Further, since the curved projections 56 of the retainer 54 are in contact with the inner surface of the base cartridge 22,
When the piston 34 is moved downward by the force limiter mechanism and the retainer 54 is pressed against the upper edge of each insertion protrusion 60 by the piston 34, the retainer 54 is reliably rotated by the frictional force between the retainer 54 and the inner surface of the base cartridge 22. Therefore, the gas vent hole 44 can be more surely opened.

Further, as described above, when the piston 34 is moved downward by the force limiter mechanism, the retainer 54 opens the gas vent hole 44, so that the packing 50 is released.
The sealing of the gas vent hole 44 due to is released. Thus, even when the gas vent hole 44 is sealed by the packing 50 as in the present embodiment, the gas discharged from the lower side to the upper side of the fitting portion 36 can still be increased during the operation of the force limiter mechanism, and the webbing can be performed. The load on the occupant by 16 can be satisfactorily limited.

Further, as described above, the retainer 5 is moved when the piston 34 is moved downward by the force limiter mechanism.
4 is rotated and the gas vent hole 44 is opened. For example, by increasing the frictional force between the retainer 54 and the inner surface of the base cartridge 22 to make the moving speed of the retainer 54 smaller than the moving speed of the piston 34, It is not always necessary to open the extraction hole 44, and by this,
It is possible to suppress damage (such as scratches) on the inner surface of the base cartridge 22 due to the retainer 54.

Moreover, since the retainer 54 is in contact with the inner surface of the base cartridge 22 at each curved projection 56, the inner surface of the base cartridge 22 is damaged (scratched or the like).
Can be further suppressed.

In the present embodiment, the gas vent hole 44
Although the packing 50 (sealing member) is fitted inside, a sheet-like sealing member may be arranged between the one end opening of the gas vent hole and the retainer (closing member).

[0063]

According to the webbing retractor of the first aspect, when the moving member is moved to the other side by the pretensioner mechanism, the closing member moves together with the moving member so that the closing member forms the gas vent hole. Since the closed state is maintained, the looseness of the webbing can be satisfactorily removed by moving the piston with a high pressure.

Further, when the moving member is moved to one side by the force limiter mechanism, the closing member is rotated to surely open the gas vent hole, so that the obstruction of the movement of the piston due to the gas is sufficiently suppressed. Therefore, the load on the occupant due to the webbing can be favorably limited. Therefore, for example, it is not always necessary to increase the frictional force between the closing member and the inner surface of the containing member, and it is possible to suppress damage to the inner surface of the containing member by the closing member.

In the webbing take-up device according to the second aspect, since the portion of the closing member on the side opposite to the moving member is in contact with the inner surface of the accommodating member, the moving member is moved to the other side by the pretensioner mechanism, and the closing member is closed. When the sheet is moved together with the moving member, the closing member can be prevented from being displaced from between the moving member and the inner surface of the containing member, and the state in which the closing member closes the gas vent hole can be favorably maintained.

Further, therefore, when the moving member is moved to one side by the force limiter mechanism and the moving member presses the moving member side portion, the closing member is rubbed by the frictional force between the closing member and the inner surface of the containing member. Can be reliably rotated, and the gas vent hole can be opened more reliably.

Further, when the rigidity of the closing member is increased, it is possible to prevent the closing member from being deformed when the pretensioner mechanism is activated, and it is possible to surely close the gas vent hole.

In the webbing retractor according to the third aspect, when the moving member is moved to the other side by the pretensioner mechanism, the sealing member keeps the gas vent hole closed, so that the webbing is loosened. Can be removed more satisfactorily.

Further, when the moving member is moved to one side by the force limiter mechanism, the sealing of the gas vent hole by the sealing member is released, so that the load on the occupant by the webbing can still be favorably limited.

[Brief description of drawings]

FIG. 1 is a rear side view showing the inside of a base cartridge when a piston is raised by a pretensioner mechanism in a webbing retractor according to an embodiment of the present invention.

FIG. 2 is a rear side view showing the inside of the base cartridge when the piston is lowered by the force limiter mechanism in the webbing retractor according to the embodiment of the present invention.

FIG. 3 is a side view showing a schematic configuration of the webbing retractor according to the embodiment of the present invention, as viewed from the left side.

FIG. 4 is a plan view showing the inside of the base cartridge in the webbing retractor according to the embodiment of the present invention.

5A and 5B are diagrams showing a piston in the webbing retractor according to the embodiment of the present invention, FIG. 5A is a side view seen from the rear side, and FIG. 5B is a side view seen from the right side. .

FIG. 6 is a perspective view showing a retainer in the webbing retractor according to the embodiment of the present invention.

[Explanation of symbols]

10 Webbing take-up device 14 winding shaft 16 webbing 18 Pretensioner mechanism 22 Base cartridge (accommodation member) 34 Piston (moving member) 36 Fitting part 44 Degassing hole 50 packing (sealing member) 54 Retainer (closure member)

Claims (3)

[Claims] 1. A moving member provided with a winding shaft for winding a webbing, a cylindrical housing member, and a fitting portion provided inside the housing member and fitted substantially to an inner surface of the housing member. In the case of an emergency of the vehicle, by supplying gas to the one side of the fitting portion in the containing member, the moving member is moved to the other side by the pressure of the gas, and the webbing is wound in the winding direction. A pretensioner mechanism for rotating the take-up shaft, and allowing the rotation of the take-up shaft in the direction of pulling out the webbing when the load of an occupant on the webbing exceeds a predetermined amount in an emergency of the vehicle to move the webbing. A webbing retractor including: a force limiter mechanism for moving a member to one side; and a gas vent hole provided in the moving member for communicating one side and the other side of the fitting portion, Close the vent hole When the moving member is moved to the other side by the pretensioner mechanism, the moving member is moved together with the moving member to close the gas vent hole. A closing member which is maintained and is rotated by pressing the moving member side portion by the moving member when the moving member is moved to one side by the force limiter mechanism, and which opens the gas vent hole; A webbing retractor comprising: 2. The webbing retractor according to claim 1, wherein the anti-moving member side portion of the closing member is brought into contact with the inner surface of the accommodating member. 3. The gas vent hole is provided so as to be sealed, and when the moving member is moved to the other side by the pretensioner mechanism, the gas vent hole is moved together with the moving member and the closing member. Is maintained, and when the moving member is moved to one side by the force limiter mechanism, the closing member opens the gas vent hole to release the hermetic seal of the gas vent hole. The webbing retractor according to claim 1 or 2, further comprising a member.