JP2018001770A - Pretensioner and seat belt device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pretensioner which can achieve weight reduction or reduction of the number of work hours during assembly, and to provide a seat belt device.SOLUTION: A pretensioner 1 includes: a wire 2 connected to webbing for restraining an occupant; a piston 3 disposed in the wire 2; a cylinder 4 which slidably houses the piston 3; a gas generator 5 which applies driving force to the piston 3; a housing 6 which connects the cylinder 4 with the gas generator 5 so that the cylinder 4 and the gas generator 5 can communicate with each other; and a bracket 7 which is connected to the housing 6 and positions the wire 2. The housing 6 includes: a protrusion 61 formed on a side surface 6s; and a step part 62 formed on the side surface 6s. The bracket 7 includes: an engagement hole 71 which engages with the protrusion 61; and a stopper 72 which may engage with the step part 62.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a pretensioner and a seat belt device, and more particularly to a pretensioner suitable for a lap belt and a seat belt device including the pretensioner.

  A vehicle such as an automobile is generally equipped with a seat belt device that restrains the occupant on a seat that includes a seat portion on which the occupant sits and a backrest portion that is positioned on the back of the occupant. Such a seat belt device includes a webbing for restraining an occupant, a retractor for winding the webbing, a guide anchor provided on the vehicle body side for guiding the webbing, a belt anchor for fixing the webbing to the vehicle body side, and a seat side surface. It has a buckle that is arranged and a tongue that is arranged on the webbing, and the passenger is restrained to the seat by the webbing by fitting the tongue to the buckle.

  Webbing when restrained by an occupant is classified into a lap belt that restrains the occupant's waist by webbing between the belt anchor and the tongue, and a shoulder belt that restrains the shoulder of the occupant at an angle by webbing between the guide anchor and the tongue. .

  In such a seat belt device, in order to improve the occupant's restraining performance at the time of a vehicle collision, it has already been proposed to arrange a pretensioner capable of retracting a webbing lap belt on a belt anchor.

  Such a pretensioner includes, for example, a wire connected to a lap belt, a piston disposed at an end of the wire, a cylinder that slidably accommodates the piston, and a piston as described in Patent Document 1. A gas generator that applies a driving force, a housing that connects the cylinder and the gas generator so that they can communicate with each other, and a bracket that is connected to the housing and positions the wire.

Japanese Patent Laid-Open No. 2003-127829

  The bracket described above is conventionally an iron part and is fixed to the housing by caulking or bolting. However, when these fixing methods are used, there is a problem that the mounting work of the bracket is troublesome and the number of work steps at the time of assembling tends to increase.

  In recent years, a material having a specific gravity smaller than that of iron (for example, aluminum) is being used for various parts from the viewpoint of weight reduction of a vehicle. However, aluminum or an aluminum alloy has a problem that it is not suitable for caulking because of its mechanical properties.

  The present invention has been devised in view of such problems, and an object of the present invention is to provide a pretensioner and a seat belt device capable of reducing the number of work steps during weight reduction or assembly.

  According to the present invention, a wire connected to a webbing that restrains an occupant, a piston disposed on the wire, a cylinder that slidably accommodates the piston, and a gas generator that applies driving force to the piston A pretensioner comprising: a housing that connects the cylinder and the gas generator so as to communicate with each other; and a bracket that is connected to the housing and positions the wire. The pretensioner includes a protrusion formed on a side surface of the pretensioner. A pre-tensioner comprising: a step portion formed on a side surface; and the bracket includes an engagement hole that engages with the protrusion, and a stopper that can be locked to the step portion. Is provided.

  According to the present invention, in a seat belt device comprising a webbing that restrains an occupant and a belt anchor that fixes the webbing to the vehicle body side, the belt anchor includes a wire connected to the webbing, A piston disposed on the wire, a cylinder that slidably accommodates the piston, a gas generator that applies a driving force to the piston, a housing that connects the cylinder and the gas generator in a communicable manner, and A pretensioner provided with a bracket connected to a housing and positioning the wire, the housing comprising a protrusion formed on a side surface and a stepped portion formed on the side surface, A seatbelt device comprising: an engagement hole that engages with a protrusion; and a stopper that can be locked to the stepped portion. It is subjected.

  In the pretensioner and the seat belt device described above, the step portion may have a recess, and the stopper may have a hook portion that can be locked in the recess.

  The bracket may have a guide portion that guides the protrusion to the engagement hole.

  The bracket may have a U-shaped cross section, the engagement hole may be disposed on the open side, and the stopper may be disposed on the closing side.

  Furthermore, the bracket may have a guide portion that guides the protrusion into the engagement hole, and the guide portion may be configured by a portion that opens a pair of side plates outward.

  According to the above-described pretensioner and seat belt device according to the present invention, the bracket is fixed to the housing by engaging the engaging hole of the bracket with the protrusion of the housing and engaging the stopper of the bracket with the step portion of the housing. can do. Therefore, according to the present invention, it is not necessary to use caulking or bolting for the mounting work of the bracket, and it is possible to reduce the weight of the apparatus or reduce the number of work steps when assembling.

It is a component expanded view which shows the pretensioner which concerns on one Embodiment of this invention. It is an enlarged view which shows the bracket shown in FIG. 1, (A) is a perspective view, (B) has shown the side view. It is explanatory drawing which shows the attachment method of a bracket, (A) has shown before attachment, (B) has shown after attachment. It is a figure which shows the modification of a bracket, (A) is a perspective view, (B) has shown the side view. 1 is an overall configuration diagram showing a seat belt device according to an embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. Here, FIG. 1 is an exploded view showing a pretensioner according to an embodiment of the present invention. 2A and 2B are enlarged views showing the bracket shown in FIG. 1, wherein FIG. 2A is a perspective view and FIG. 2B is a side view. 3A and 3B are explanatory views showing a method of attaching the bracket, where FIG. 3A shows before attachment and FIG. 3B shows after attachment.

  A pretensioner 1 according to an embodiment of the present invention includes, for example, a wire 2 connected to a webbing that restrains an occupant and a piston 3 disposed on the wire 2 as shown in FIGS. A cylinder 4 that slidably accommodates the piston 3, a gas generator 5 that applies a driving force to the piston 3, a housing 6 that connects the cylinder 4 and the gas generator 5 so that they can communicate with each other, and a connection to the housing 6. The housing 6 includes a projection 61 formed on the side surface 6 s and a stepped portion 62 formed on the side surface 6 s. The bracket 7 is associated with the projection 61. An engaging hole 71 to be engaged and a stopper 72 that can be locked to the stepped portion 62 are provided.

  The pretensioner 1 has a function as a belt anchor, and is fixed to the vehicle body by inserting bolts into a fixing hole 73 formed in the bracket 7 and a fixing hole 63 formed in the housing 6. A holder 21 is connected to one end of the wire 2, and the holder 21 is connected to a ferrule 22. The ferrule 22 is connected to the end of the webbing. The webbing connected to the wire 2 via the ferrule 22 constitutes a lap belt that restrains the occupant's waist when restraining the occupant.

  The other end of the wire 2 is inserted into the housing 6 via the bracket 7 and connected to the wire end 23 in the cylinder 4. A wire guide 64 for guiding the wire 2 is arranged in the housing 6 and is positioned by a sleeve 65. The wire 2 is inserted through the wire guide 64 and the sleeve 65.

  A piston 3 is slidably disposed in the cylinder 4, and the wire 2 is inserted into the piston 3 and then connected to the wire end 23. An O-ring 31 that improves airtightness is disposed on the outer periphery of the piston 3. In addition, a ball and a ball ring 32 are arranged in the middle portion of the piston 3 to prevent the reverse movement.

  The gas generator 5 is fixed to the housing 6 by a keeper 51. The gas generator 5 is connected to, for example, an acceleration sensor that detects a vehicle collision, and is activated when the vehicle collides to eject high-pressure gas into the housing 6. The high-pressure gas ejected into the housing 6 presses the piston 3 and moves the piston 3 in a direction away from the housing 6. As the piston 3 moves, the wire 2 is drawn into the housing 6 and the cylinder 4 to tighten the webbing (lap belt).

  In general, the cylinder 4 is often arranged along the longitudinal direction of the vehicle body. In order to guide the wire 2 from the wire end 23 in the cylinder 4 to the ferrule 22 (holder 21) connected to the webbing, It is necessary to bend or curve the wire 2 on the way. In the present embodiment, the wire 2 inserted through the bracket 7 is bent upward, and elastic deformation is suppressed by the rivet 74 fixed to the bracket 7.

  The configuration of the pretensioner 1 described above is merely an example, and is not limited to the illustrated configuration. For example, the configuration of parts such as the wire guide 64, the sleeve 65, and the piston 3 and the arrangement of the gas generator 5 may be other configurations.

  As shown in FIG. 1, the cylinder 4 is connected to one end of the housing 6, and the bracket 7 is connected to the other end on the opposite side. As shown in FIG. 3A, the other end of the housing 6 has a convex portion 6 c in which a fixing hole 63 is formed, and a protrusion 61 and a stepped portion 62 are formed on the outer peripheral portion close to the fixing hole 63. Has been.

  The protrusion 61 has a shape protruding outward from the side surface 6 s of the housing 6. The protrusion 61 has, for example, a rectangular parallelepiped shape, a cube shape, a hemispherical shape, or the like, and may have a tapered surface formed in the moving direction of the bracket 7. The protrusions 61 are formed on the left and right side surfaces 6 s of the housing 6.

  The step portion 62 has a shape that is recessed inward from the side surface 6 s of the housing 6. As shown in FIG. 3A, the stepped portion 62 may be formed by a part of the groove formed in the side surface 6s. The step portion 62 is formed, for example, along the longitudinal direction of the housing 6 (or the cylinder 4). The step portion 62 is formed on the side surfaces 6 s on the left and right sides of the housing 6. Further, the step portion 62 may have a recess 62c in a part in the longitudinal direction. For example, a part of the stopper 72 of the bracket 7 is locked to the recess 62c.

  As shown in FIG. 2A, the bracket 7 has, for example, a U-shaped cross section including a first side plate 7a, a second side plate 7b, and a bottom plate 7c. As shown in FIG. 3 (b), the first side plate 7a and the second side plate 7b are formed in a substantially central portion and are formed in a fixing hole 73 through which a fixing bolt is inserted, and are formed in an outer peripheral portion to fix the rivet 74. Rivet holes 74a for the purpose. The bending angle of the wire 2 is adjusted by a linear inclination angle θ connecting the center of the fixing hole 73 and the center of the rivet hole 74a.

  An engagement hole 71 is formed on the opposite side of the rivet hole 74a across the fixing hole 73. A guide portion 75 for guiding the protrusion 61 of the housing 6 to the engagement hole 71 is formed in front of the engagement hole 71. As illustrated in FIG. 3A, the guide portion 75 is configured by a portion that is deformed so that a part of the first side plate 7 a and the second side plate 7 b is opened outward. That is, the guide portion 75 has a gap between the first side plate 7 a and the second side plate 7 b on the front side away from the engagement hole 71 between the first side plate 7 a and the second side plate 7 b on the side close to the engagement hole 71. It is formed to be larger than the gap. The engagement hole 71 is disposed on the open side of the bracket 7 (the side where the bottom plate 7c is not formed).

  For example, as shown in FIG. 3B, the stopper 72 includes a portion that protrudes outward from the bracket 7 substantially in parallel to the guide portion 75. The stopper 72 has a shape that can be inserted into a groove that forms the stepped portion 62 of the housing 6. In addition, a hook portion 72 f that can be locked to a recess 62 c formed in the stepped portion 62 of the housing 6 may be provided below the distal end portion of the stopper 72. As shown in the figure, the stopper 72 is disposed below the engagement hole 71, that is, on the closed side of the bracket 7 (the side on which the bottom plate 7c is formed).

  Thus, by combining the engagement hole 71 and the stopper 72, the rotational movement of the bracket 7 that occurs when the engagement hole 71 is engaged with the protrusion 61 can be suppressed by the stopper 72, and the bracket 7 is dropped. Can be suppressed. Further, by forming the hook portion 72f at the tip of the stopper 72, the stopper 72 can be locked to the side surface 6s of the housing 6, and the positions of the fixing hole 73 of the bracket 7 and the fixing hole 63 of the housing 6 are effective. Can be matched.

  Further, by disposing the engagement hole 71 on the opening side with respect to the stopper 72, when the engagement hole 71 is engaged with the projection 61, the portion where the guide portion 75 is formed can be easily spread outward. Thus, the protrusion 61 can be easily engaged with the engagement hole 71.

  Here, a method of attaching the bracket 7 to the housing 6 will be described with reference to FIGS. 3 (A) and 3 (B). The bracket 7 is attached to the convex portion 6 c of the housing 6. The bracket 7 is moved closer to the housing 6 (in the direction of the arrow in the figure) so that the stopper 72 is inserted into the groove portion that forms the stepped portion 62 formed on the side surface 6s of the housing 6. The protrusion 61 of the housing 6 comes into contact with the guide portion 75, and the guide portion 75 is pushed and spread. Further, when the bracket 7 is pushed into the housing 6, the protrusion 61 engages with the engagement hole 71 as shown in FIG. At this time, the hook portion 72f of the stopper 72 is engaged with the concave portion 62c of the stepped portion 62 substantially simultaneously.

  According to the pretensioner 1 according to this embodiment described above, the engagement hole 71 of the bracket 7 is engaged with the protrusion 61 of the housing 6, and the stopper 72 of the bracket 7 is engaged with the stepped portion 62 of the housing 6. The bracket 7 can be easily fixed to the housing 6. Therefore, according to this embodiment, it is not necessary to use caulking or bolting for the mounting work of the bracket 7, and it is possible to reduce the weight of the apparatus or reduce the work man-hours during assembly.

  Further, by forming the first side plate 7a and the second side plate 7b of the bracket 7 in the same shape, that is, symmetrically, for example, the pretensioner 1 used in the seat belt device on the driver's seat side and the seat belt on the passenger seat side The bracket 7 having the same shape can be used in the pretensioner 1 used in the apparatus, and parts can be shared. Therefore, by using the bracket 7 described above, it is not necessary to select the type of the bracket 7 at the time of assembly, and the number of work steps can be reduced.

  Next, a modified example of the bracket 7 will be described with reference to FIGS. 4 (A) and 4 (B). Here, FIG. 4 is a figure which shows the modification of a bracket, (A) is a perspective view, (B) has shown the side view. In addition, about the same structure as the bracket 7 shown to FIG. 2 (A) and FIG. 2 (B), the same code | symbol is attached | subjected and the overlapping description is abbreviate | omitted.

  In the modified example of the bracket 7 shown in FIGS. 4A and 4B, the hook portion is not formed at the tip of the stopper 72. In this modification, the guide portion 76 that guides the protrusion 61 of the housing 6 to the engagement hole 71 is formed by a tapered surface. The protrusion 61 can be smoothly guided to the engagement hole 71 by such a tapered surface (guide portion 76). In addition, when the bracket 7 of this modification is used, the recessed part formed in the level | step-difference part 62 of the bracket 6 can be abbreviate | omitted.

  The bracket 7 shown in FIGS. 2A and 4A described above is made of, for example, a material having a specific gravity smaller than that of iron (for example, aluminum, an aluminum alloy). Specifically, the bracket 7 may be manufactured by aluminum die casting. By adopting a material having a specific gravity smaller than that of iron, the weight of the bracket 7 can be effectively reduced.

  Next, a seat belt device according to an embodiment of the present invention will be described with reference to FIG. Here, FIG. 5 is an overall configuration diagram showing the seat belt device according to the embodiment of the present invention. In FIG. 5, for convenience of explanation, components other than the seat belt device are illustrated by a one-dot chain line.

  A seat belt device 100 according to the present embodiment shown in FIG. 5 includes a webbing W that restrains an occupant, a retractor 101 that winds the webbing W, a guide anchor 102 that is provided on the vehicle body side and guides the webbing W, A belt anchor 103 that fixes the webbing W to the vehicle body side, a buckle 104 that is disposed on the side surface of the seat S on which an occupant is seated, and a tongue 105 that is disposed on the webbing W are provided. The pretensioner 1 shown in FIG.

  The seat belt device shown in FIG. 5 is a seat belt device disposed in a passenger seat. The webbing W has one end connected to the retractor 101 and the other end connected to the belt anchor 103. An intermediate portion of the webbing W is inserted through the belt anchor 103 and the tongue 105. The occupant seated on the seat S can be restrained by the webbing W by fitting the tongue 105 to the buckle 104.

  When the occupant is restrained, the webbing W includes a lap belt that restrains the occupant's waist by the webbing W between the belt anchor 103 and the tongue 105, and a shoulder belt that restrains the shoulder of the occupant by the webbing W between the guide anchor 102 and the tongue 105. And can be classified.

  The belt anchor 103 is configured by the pretensioner 1 shown in FIG. Specifically, the pretensioner 1 is fixed to the vehicle body by inserting a bolt through the fixing hole 73 of the bracket 7 and the fixing hole 63 of the housing 6 and fixing the bolt to the vehicle body side. Thus, by arranging the pretensioner 1 on the belt anchor 103, the occupant restraint performance at the time of a vehicle collision can be improved.

  Further, by using the bracket 7 shown in FIG. 2 (A) or FIG. 4 (A) for the pretensioner 1, it is possible to reduce the weight of the seat belt device 100 and to reduce the work man-hours during assembly. Moreover, the weight reduction of the seatbelt apparatus 100 can be achieved effectively by forming the bracket 7 with a material having a specific gravity smaller than that of iron.

  The present invention is not limited to the above-described embodiment. For example, the seat belt device 100 may be a seat belt device used for a driver seat or a rear seat of a vehicle, or a seat used for a vehicle other than a vehicle. Of course, various modifications can be made without departing from the spirit of the present invention, such as a belt device.

DESCRIPTION OF SYMBOLS 1 Pretensioner 2 Wire 3 Piston 4 Cylinder 5 Gas generator 6 Housing 6c Protruding part 6s Side surface 7 Bracket 7a First side plate 7b Second side plate 7c Bottom plate 21 Holder 22 Ferrule 23 Wire end 31 O ring 32 Ball ring 51 Keeper 61 Protrusion 62 Stepped portion 62c Recessed portion 63 Fixed hole 64 Wire guide 65 Sleeve 71 Engagement hole 72 Stopper 72f Hook portion 73 Fixed hole 74 Rivet 74a Rivet holes 75, 76 Guide portion 100 Seat belt device 101 Retractor 102 Guide anchor 103 Belt anchor 104 Buckle 105 Tong

Claims (6)

A wire connected to a webbing that restrains an occupant, a piston disposed on the wire, a cylinder that slidably accommodates the piston, a gas generator that applies a driving force to the piston, the cylinder, and the cylinder In a pretensioner comprising a housing that connects a gas generator so as to communicate with each other, and a bracket that is connected to the housing and positions the wire.
The housing includes a protrusion formed on a side surface and a step portion formed on the side surface,
The bracket includes an engagement hole that engages with the protrusion, and a stopper that can be locked to the stepped portion.
Pretensioner characterized by that.   The pretensioner according to claim 1, wherein the step portion has a recess, and the stopper has a hook portion that can be locked to the recess.   The pretensioner according to claim 1, wherein the bracket has a guide portion that guides the protrusion to the engagement hole.   The pretensioner according to claim 1, wherein the bracket has a U-shaped cross section, the engagement hole is disposed on an open side, and the stopper is disposed on a closed side.   The said bracket has a guide part which guides the said processus | protrusion to the said engagement hole, This guide part is comprised by the part which opened a pair of side plate outside. Pretensioner. In a seat belt device comprising a webbing that restrains an occupant and a belt anchor that fixes the webbing to the vehicle body side,
The said belt anchor is equipped with the pretensioner as described in any one of Claims 1-5, The seatbelt apparatus characterized by the above-mentioned.