JP5501138B2 - Webbing take-up device - Google Patents

Description

  The present invention relates to a webbing take-up device that takes up a webbing belt to be worn by an occupant of a vehicle.

  As one of the locking mechanisms of the webbing take-up device, there is a VSIR (vehicle body sensitive retractor) that detects the sudden deceleration state of the vehicle and prevents the spool (winding shaft) from rotating in the pull-out direction. This mechanism is provided with an acceleration sensor. For example, an inertial body is disposed on the concave surface of the housing, and a transmission member (lever) is slidably mounted on the inertial body (for example, Patent Document 1). reference). Here, in the following Patent Document 1, the transmission member is supported by a pin so as to be swingable, and both end sides of the pin are fitted in holes of a column in the housing.

Japanese Laid-Open Patent Publication No. 54-25020

  However, since the pair of struts are arranged away from each other on both sides of the base end portion of the transmission member, when the pin is fitted into the hole, one of the struts is distorted or tilted. There is a possibility that the relative positional relationship between the columns is shifted. If the relative positional relationship between the columns is shifted in this way, the axial direction of the pin is also inclined with respect to the direction to be set, so that the sensor performance is difficult to stabilize.

  An object of the present invention is to obtain a webbing take-up device capable of stabilizing the sensor performance of an acceleration sensor in consideration of the above facts.

According to a first aspect of the present invention, there is provided a webbing take-up device of the present invention, in which a webbing belt mounted on a vehicle occupant is wound in layers, and the spool rotates in the pull-out direction when the webbing belt is pulled out, and the spool A rotating body that is coaxially arranged on the shaft end side of the spool and is connected to the spool so as to be able to follow and rotate, and an acceleration sensor that stops rotation of the rotating body in the pull-out direction by operating when the vehicle suddenly decelerates; Locking means for locking the rotation of the spool in the pull-out direction by operating when the rotation of the acceleration sensor causes relative rotation between the spool and the rotating body, An inertial body that inertially moves at an acceleration of a predetermined value or more, a housing that supports the inertial body, and a rotational movement that is pushed by the inertial movement of the inertial body. A lever that engages with the rotating body and prevents the rotating body from rotating in the pull-out direction, a shaft member that penetrates the housing and the lever, and serves as an axis of rotational movement of the lever, the lever, and the lever A pair of insertion portions formed on either side of the shaft member and provided on both ends of the shaft member, the shaft member being inserted so as to be relatively rotatable about the axis, and any of the lever and the housing Kano is other to be formed is disposed between the pair of insertion portions, have a, a press-fitting portion to which the shaft member is press-fitted, the press-fit portion includes a pair of cylindrical shape wherein the shaft member is inserted And a press-fitting rib that is formed in a connecting portion that connects the pair of cylindrical portions and presses the shaft member toward the upper surface side or the lower surface side of the inner peripheral surface of the cylindrical portion .

  According to the webbing take-up device of the present invention described in claim 1, the webbing to be mounted on the vehicle occupant is wound up in layers on the spool, and the webbing belt is pulled out from the spool, whereby the spool is pulled out. Rotated in the direction. Further, a rotating body arranged coaxially on the shaft end side of the spool is connected to the spool so as to be able to follow and rotate. The rotating body is stopped from rotating in the pull-out direction when the acceleration sensor is activated during sudden deceleration of the vehicle. Further, when the acceleration sensor is operated, a relative rotation is generated between the spool and the rotating body, whereby the lock unit is operated to lock the rotation of the spool in the pull-out direction.

  In the acceleration sensor, an inertial body is supported by a housing, and the inertial body moves inertially with an acceleration of a predetermined value or more. The lever is pushed and rotated by the inertial movement of the inertial body, so that the lever is engaged with the rotation body and prevents the rotation body from rotating in the pull-out direction. A shaft member serving as a shaft for rotational movement of the lever penetrates the housing and the lever. A pair of insertion portions are formed on either one of the lever and the housing and are provided at both ends of the shaft member. The shaft member is inserted into the pair of insertion portions so as to be rotatable around the axis. Has been. On the other hand, the press-fitting portion to which the shaft member is press-fitted and fixed is formed on the other of the lever and the housing and is disposed between the pair of insertion portions. As described above, the shaft member is press-fitted and fixed to the press-fitting portion disposed between the pair of insertion portions, so that the relative positional relationship between the both sides in the axial direction in the press-fitting portion is difficult to shift, and the axial direction of the shaft member is accurate. Can be set well.

Further, according to the webbing retractor of this, the shaft member is inserted into the pair of cylindrical portion of the press-fit portion. In addition, a press-fitting rib is formed in the connecting part that connects the pair of cylindrical parts in the press-fitting part, and the shaft member is pressed against the upper surface side or the lower surface side of the inner peripheral surface of the cylindrical part by the press-fitting rib. For this reason, when the lever rotates in accordance with the inertial movement of the inertial body, the vertical movement at the press-fitting portion of the shaft member is suppressed.

The webbing take-up device according to a second aspect of the present invention is the webbing retractor according to the first aspect , wherein an inclined portion that is tapered toward the terminal side is formed at an end portion in the axial direction of the shaft member. Has been.

According to the webbing take-up device of the present invention described in claim 2 , since the inclined portion that is inclined toward the terminal side is formed at the end portion in the axial direction of the shaft member, At the time of press-fitting into the press-fitting part, after the inclined part of the shaft member comes into contact with the press-fitting rib, the inclined part gradually rides on the press-fitting rib. For this reason, since the shaft member is smoothly press-fitted into the press-fitting portion and positioned, the relative positional relationship between both side portions of the press-fitting portion in the axial direction is more difficult to shift.

  As described above, according to the webbing retractor according to the first aspect of the present invention, there is an excellent effect that the sensor performance of the acceleration sensor can be stabilized.

Further, according to the webbing take-up device of this has since vertical movement of the press-fit portion of the shaft member during the operation of the acceleration sensor can be suppressed, an excellent effect that the sensor performance of the acceleration sensor can be further stabilized .

According to the webbing take-up device according to claim 2 , it is possible to further stabilize the sensor performance of the acceleration sensor by making the relative positional relationship between the both side portions in the axial direction in the press-fit portion more difficult to shift. It has the effect.

It is a side view which shows the webbing winding device concerning a 1st embodiment of the present invention in the state where a sensor cover was removed. 1 is an exploded perspective view showing a webbing take-up device according to a first embodiment of the present invention. It is explanatory drawing for demonstrating assembly of the acceleration sensor in the webbing winding device concerning a 1st embodiment of the present invention. FIG. 3A is a perspective view showing a state before a pin is assembled to the upper part of the acceleration sensor. FIG. 3B is a perspective view showing a state where pins are assembled from the state of FIG. It is a longitudinal cross-sectional view (cross-sectional view in alignment with line 4-4 of FIG. 3 (B)) which shows the upper part of the acceleration sensor in the webbing take-up device according to the first embodiment of the present invention. FIG. 5 is an enlarged cross-sectional view taken along line 5-5 in FIG. It is explanatory drawing which shows the state in which a pin is press-fit in the press-fit part of the sensor lever shown in FIG. FIG. 6A shows a state where the tip of the pin is inserted into the cylindrical portion. FIG. 6B shows a state in which the inclined portion at the tip of the pin is in contact with the press-fitting rib. FIG. 6 (C) shows a state in which the inclined portion of the pin tip exceeds the first press-fitting rib. It is a disassembled perspective view which shows the state which isolate | separated the acceleration sensor and sensor holder of the webbing winding device which concerns on the 1st Embodiment of this invention. It is a disassembled perspective view in the state which decomposed | disassembled the upper part of the acceleration sensor of the webbing winding apparatus which concerns on the 2nd Embodiment of this invention. It is a longitudinal cross-sectional view of the webbing take-up device according to the second embodiment of the present invention.

[First Embodiment]
A webbing take-up device according to a first embodiment of the present invention will be described with reference to FIGS. Note that an arrow A appropriately shown in these drawings indicates a webbing belt winding rotation direction (winding direction), and an arrow B indicates a webbing belt pulling rotation direction (drawing direction).

  FIG. 1 is a side view showing a state where the sensor cover 60 (see FIG. 2) is removed from the webbing take-up device 10 according to the present embodiment. FIG. 2 is an exploded perspective view showing the overall configuration of the webbing take-up device 10. In FIG. 2, some of the components are not shown.

  As shown in FIG. 2, the webbing take-up device 10 includes a metal frame 12 formed in a U shape in plan view. The frame 12 is fixed to the lower end portion side of the vehicle body side by bolt fastening, and although not shown, in the present embodiment, the frame 12 is disposed so as to be inclined obliquely in a vehicle side view. Note that the installation angle (tilt angle) of the frame 12 with respect to the vehicle may vary depending on the vehicle type.

  Arrangement holes 112A and 112B are formed in the both side portions 12A and 12B of the frame 12 so as to penetrate coaxially by punching. The arrangement hole 112 </ b> A is an internal tooth ratchet, and high-strength ratchet teeth 14 (elements grasped as “lock teeth” in a broad sense) are formed.

  Cylindrical spools 16 that function as winding shafts are supported on both side portions 12A and 12B of the frame 12 via other members. A rotating shaft 16A is integrally provided at one axial end portion of the axial center portion of the spool 16, and an inner end of a mainspring spring (not shown) that is grasped as "biasing means" in a broad sense. Is locked. As a result, the spool 16 is constantly urged to rotate in the winding direction (see the arrow A direction).

  On the other hand, a lock base 22 is integrally provided at the other axial end of the spool 16. A rotation shaft 16B protrudes from the lock base 22, and the spool 16, the rotation shaft 16B, and the lock base 22 are coaxially and integrally rotatable. The rotating shaft 16B is provided coaxially with the rotating shaft 16A, and a bush 19 is fixed to the tip of the rotating shaft 16B. The bush 19 is rotatably supported by a bearing portion 30 </ b> A formed on the sensor holder 30 to be described later, whereby the rotation shaft 16 </ b> B is rotatably supported by the sensor holder 30 via the bush 19. In addition, a proximal end portion of a webbing belt 18 to be attached to a vehicle occupant is locked to the spool 16. The webbing belt 18 is wound in layers on the spool 16, and the spool 16 rotates in the pull-out direction (see arrow B direction) when the webbing belt 18 is pulled out.

  The lock base 22 is formed with a locking projection 22A for attaching a return spring 28, which will be described later, and a recess 22B. A lock plate 24 is accommodated in the recess 22 </ b> B of the lock base 22. Lock teeth 24 </ b> C that can be engaged with the ratchet teeth 14 of the frame 12 are formed at the tip of the plate body 24 </ b> B of the lock plate 24. In a state where the plate body 24 </ b> B is completely accommodated in the recess 22 </ b> B of the lock base 22, the lock teeth 24 </ b> C are held at positions separated from the ratchet teeth 14 of the frame 12. On the other hand, the lock teeth 24C are engaged with the ratchet teeth 14 when the lock plate 24 rotates (swings) and comes out of the recess 22B.

  Further, on the outside of one side portion 12A of the frame 12, a V gear 26 as a rotating body between the sensor holder 30 and the lock base 22 (which is an element grasped as a “lock wheel” in a broad sense). Is arranged. The V gear 26 is made of resin and has a substantially disk shape, and is accommodated in the sensor holder 30. A cylindrical boss 26 </ b> A having a pair of resin claws on the inner peripheral surface is formed at the axial center of the V gear 26. By inserting the rotating shaft 16B provided on the shaft end side of the spool 16 into the boss 26A, the V gear 26 is coaxially disposed on the shaft end side of the spool 16 and is rotatably attached.

  A long guide groove (not shown) is formed on the surface of the V gear 26 on the lock base 22 side, and a guide protrusion 24 </ b> A standing from the lock plate 24 is inserted into the guide groove. As a result, the V gear 26 can be rotated relative to the lock base 22 (spool 16) within a predetermined rotation angle range, and the lock base 22 (spool 16) is pulled out with respect to the V gear 26 (arrow). When the relative rotation is performed in the direction B), the guide groove (not shown) moves the guide protrusion 24A from the inside to the outside, and the lock teeth 24C of the lock plate 24 can be engaged with the ratchet teeth 14 of the frame 12. To guide you to.

  A locking projection (not shown) is provided on the surface of the V gear 26 on the lock base 22 side. A return spring 28 is bridged between the locking projection and the locking protrusion 22A of the lock base 22 described above. The return spring 28 is a compression coil spring, and urges the V gear 26 in the pulling direction (see the arrow B direction) with respect to the lock base 22. The guide protrusion 24A is locked to one end of the guide groove by the urging force of the return spring 28, and normally the V gear 26 rotates following the lock base 22 (spool 16). ing.

  In the present embodiment, the lock mechanism portion 20 as a lock means is configured including the guide groove (not shown) of the V gear 26, the lock plate 24, and the ratchet teeth 14 of the frame 12. Is operated by relative rotation between the spool 16 and the V gear 26 to lock the rotation of the spool 16 in the pulling direction (see arrow B direction).

  The V gear 26 is formed with an accommodating portion 26B that opens toward the sensor holder 30 side. A W pawl 36, a sensor spring 38, and the like are accommodated in the accommodating portion 26B. Although the detailed description is omitted, the W pawl 36 is disposed so as to be rotatable (swingable) around the axis of the support shaft 26 </ b> C standing in the housing portion 26 </ b> B, and the engaging teeth of the W pawl 36. 36A is engageable with ratchet teeth (not shown) of the sensor holder 30. Further, the W pawl 36 is abutted against a stopper 26 </ b> D standing in the housing portion 26 </ b> B by being urged by the sensor spring 38 around the support shaft 26 </ b> C toward the drawing direction. As a result, the lock standby state is set during normal operation, and when the webbing belt 18 is suddenly pulled out, the W pawl 36 rotates in the winding direction around the support shaft 26C, and the engaging teeth 36A of the W pawl 36 move. By engaging with ratchet teeth (not shown) of the sensor holder 30, rotation of the spool 16 in the pull-out direction is prevented. A W sensor 34 (sensor constituting WSIR) is configured including the W pawl 36, the sensor spring 38, and the ratchet teeth (not shown) of the sensor holder 30.

  As shown in FIGS. 1 and 2, external teeth 26 </ b> E are integrally formed on the outer peripheral portion of the V gear 26. The engaging portion 46C of the sensor lever 46 (pawl) of the acceleration sensor 40 (V sensor) can be engaged with the external teeth 26E of the V gear 26 while passing through the penetrating portion 30B (see FIG. 1) of the sensor holder 30. It is said that. The acceleration sensor 40 is accommodated in the holder portion 32 of the sensor holder 30.

  The holder part 32 is provided in the lower end part of the sensor holder 30, and as shown in FIG. 2, it is formed in a substantially box shape with the sensor cover 60 side and the like opened. The installation posture of the holder portion 32 is determined in accordance with the installation posture of the frame 12 with respect to the vehicle. In the present embodiment, as shown in FIG. It arrange | positions so that it may incline to the side (arrow L1). A pair of groove portions 32 </ b> B are formed on the side walls 32 </ b> A on both sides of the holder portion 32. The pair of groove portions 32B open on opposite sides and extend in a direction parallel to the bottom wall 32C as an example in the present embodiment. In addition, a rib-like engaged portion 32C is formed at an intermediate portion in the extending direction of the groove portion 32B.

  An insertion portion 44B formed in the housing 44 of the acceleration sensor 40 is inserted into the groove portion 32B. The housing 44 is formed in a substantially U shape when viewed from the front, and insertion portions 44B are formed in the vertical wall portions 44A on both sides. The insertion portion 44B is formed to extend obliquely with respect to the vertical direction of the vertical wall portion 44A, and an engaging claw that can be engaged with the engaged portion 32C of the groove portion 32B is provided at the intermediate portion in the extending direction. A portion 44C is formed. That is, the insertion portion 44B is inserted into the groove portion 32B of the holder portion 32 and the engaging claw portion 44C is engaged with the engaged portion 32C, whereby the housing 44 is positioned and mounted on the holder portion 32, and the housing 44 is arranged in a posture not tilted.

  The housing 44 has a concave rolling surface 44 </ b> D formed at the bottom center. A ball 42 as an inertia body is placed (supported) on the rolling surface 44 </ b> D of the housing 44. The ball 42 is adapted to move inertially at an acceleration of a predetermined value or more and roll on the rolling surface 44D.

  A sensor lever 46 is supported on the upper end of one side of the housing 44 so as to be rotatable (swingable). A pin 48 (shaft) as a shaft member that serves as an axis of rotational movement of the sensor lever 46 passes through the housing 44 and the sensor lever 46. More specifically, a pair of insertion portions 50 are formed at the upper end portion of the housing 44, and the pair of insertion portions 50 are provided at both ends of the pin 48, and the pin 48 is relative to its axis. It is inserted in a rotatable manner. In other words, the pair of insertion portions 50 function as shaft support portions that rotatably support both end sides of the pin 48. The sensor lever 46 is formed with a press-fit portion 52 disposed between the pair of insertion portions 50, and a pin 48 is press-fitted and fixed to the press-fit portion 52.

  FIG. 3 is an enlarged perspective view of the insertion portion 50, the press-fit portion 52, and the surrounding portion thereof, and is shown in a perspective view. 3A shows a state before the pin 48 is inserted, and FIG. 3B shows a state after the pin 48 is inserted. FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. FIG. 5 is an enlarged cross-sectional view taken along line 5-5 in FIG.

  As shown in FIGS. 3 and 4, an inclined portion 48 </ b> A is formed at the end of the pin 48 in the axial direction so as to be tapered toward the terminal side. The press-fit portion 52 includes a pair of cylindrical portions 54 into which the pins 48 are inserted. As shown in FIG. 5, the inner diameter of the cylindrical portion 54 is set slightly larger than the outer diameter of the pin 48. As shown in FIGS. 3 and 4, the pair of cylindrical portions 54 are connected by a connecting portion 56, and the connecting portion 56 has a groove portion 56 </ b> A continuous with the lower surface of the inner peripheral surface of the cylindrical portion 54. Is formed. The groove portion 56 </ b> A extends in the connecting direction for connecting the cylindrical portions 54. In addition, a pair of press-fitting ribs 58 is formed in the connecting portion 56 at an intermediate portion in the extending direction of the groove portion 56A. As shown in FIG. 3A, the press-fitting rib 58 is formed so as to be orthogonal to the extending direction of the groove portion 56A in plan view, and as shown in FIG. The position is set to be pressed against the upper surface 54A side of the inner peripheral surface of the portion 54. As described above, the press-fit portion 52 shown in FIGS. 3 and 4 includes a pair of cylindrical portions 54 and press-fit ribs 58.

  As shown in FIG. 4, in the state where the acceleration sensor 40 is mounted, one end side (right side in FIG. 4) of the pin 48 in the axial direction faces the vertical wall portion of the sensor holder 30. The other end side of the pin 48 in the axial direction (left side in FIG. 4) faces the vertical wall portion of the sensor cover 60. The vertical wall portion of the sensor holder 30 and the vertical wall portion of the sensor cover 60 serve as a retaining portion for the pin 48.

  Further, as shown in FIG. 1, the sensor lever 46 includes an arm portion 46A extending from the press-fit portion 52 at a substantially right angle with respect to the pin 48, and is integrally formed on the distal end side of the arm portion 46A. A dish-shaped contact part 46B is provided, and an engaging part 46C extending from the contact part 46B is further provided. The engaging portion 46C is formed in a substantially L shape in a plan view (not shown), and the end portion arranged substantially parallel to the pin 48 in the assembled state is the external tooth 26E of the V gear 26 as described above. Can be engaged. Further, the contact portion 46B is placed on the ball 42 by its own weight, and the engagement portion 46C is separated from the external teeth 26E of the V gear 26 in a normal state (the state shown in FIG. 1). Held in position. When the vehicle suddenly decelerates, the sensor lever 46 is engaged with the external teeth 26E of the V gear 26 by the contact portion 46B being pushed by the inertial movement of the ball 42 and rotating (swinging) about the pin 48. In addition, the rotation of the V gear 26 in the drawing direction (see the arrow B direction) is prevented.

  That is, the acceleration sensor 40 is configured to stop the rotation of the V gear 26 in the pull-out direction by operating when the vehicle is suddenly decelerated. The direction in which the pin 48 described above is pressed against the inner peripheral surface of the cylindrical portion 54 by the press-fitting rib 58 (see FIG. 4) is set in accordance with the load direction acting on the pin 48 side when the sensor lever 46 is rotated. Is.

  In the present embodiment, in order to stabilize the sensor performance of the acceleration sensor 40, the orientation of the pair of insertion portions 50 of the housing 44 is set so that the axial direction of the pin 48 is horizontal. That is, since the installation angle of the frame 12 with respect to the vehicle may vary depending on the vehicle type, the orientation of the holder portion 32 of the sensor holder 30 shown in FIG. 7 may vary depending on the vehicle type, but in the insertion portion 44B of the molded housing 44 By setting the extending direction according to the vehicle type, the axial direction of the pin 48 becomes horizontal. Similarly, in order to stabilize the sensor performance of the acceleration sensor 40, the shape of the engaging portion 46C of the sensor lever 46 depends on the installation angle of the webbing retractor 10 (frame 12) shown in FIG. 1 with respect to the vehicle. And the positional relationship between the engaging portion 46C of the sensor lever 46 and the external teeth 26E of the V gear 26 is set to be more appropriate.

(Action / Effect)
Next, the operation and effect of the above embodiment will be described.

  As shown in FIG. 2, in the webbing take-up device 10 configured as described above, normally, the W pawl 36 of the W sensor 34 is urged around the axis of the support shaft 26 </ b> C to the drawing direction side by the urging force of the sensor spring 38. In addition, since the sensor lever 46 of the acceleration sensor 40 is held on the ball 42 by its own weight, the W sensor 34 and the acceleration sensor 40 are in an inoperative state. For this reason, the spool 16 can freely rotate in both the drawing direction and the winding direction.

  On the other hand, when the webbing belt 18 is suddenly pulled out, the W sensor 34 operates, and when the vehicle suddenly decelerates, the acceleration sensor 40 operates. Hereinafter, the case where the acceleration sensor 40 shown in FIG. 1 operates will be described.

  When the vehicle suddenly decelerates, the ball 42 of the acceleration sensor 40 moves inertially at an acceleration of a predetermined value or more and rolls on the rolling surface 44D of the housing 44. Along with this, the abutting portion 46B and the engaging portion 46C of the sensor lever 46 placed in contact with the ball 42 rotate around the axis of the pin 48, and the engaging portion 46C becomes the external teeth 26E of the V gear 26. Is engaged. As a result, the rotation of the V gear 26 in the pull-out direction is prevented, so that a relative rotation occurs between the V gear 26 and the spool 16 shown in FIG. As a result, the guide protrusion 24A of the lock plate 24 is guided to the outer end side of the guide groove (not shown) of the V gear 26, and the lock teeth 24C of the lock plate 24 reach the position where it can engage with the ratchet teeth 14 of the frame 12. Guided.

  When the tip of the claw of the lock tooth 24C of the lock plate 24 is guided to the position where the ratchet tooth 14 can be engaged with the tip of the ratchet tooth 14, the lock tooth is rotated along with the rotation of the spool 16 in the pull-out direction (see arrow B direction). The tooth tip of 24C reaches the root of the ratchet tooth 14. As a result, the lock plate 24 is securely locked by the ratchet teeth 14, the spool 16 is prevented from rotating in the pull-out direction (see the arrow B direction), and further pull-out of the webbing belt 18 is restricted. As a result, the occupant's body about to move inertially toward the front side of the vehicle is reliably restrained and held by the webbing belt 18.

  Here, as shown in FIG. 3B and FIG. 4, the pin 48 that is the axis of rotational movement of the sensor lever 46 has a pair of insertion portions 50 formed in the housing 44 at both ends thereof. It is inserted so as to be capable of relative rotation around the axis, and is press-fitted and fixed to a press-fit part 52 of the sensor lever 46 disposed between the pair of insertion parts 50. For this reason, the relative positional relationship between the axially opposite side portions of the press-fit portion 52 (the cylindrical portion 54 on the right side in the drawing and the cylindrical portion 54 on the left side in the drawing) is unlikely to occur. Supplementally, for example, a pair of pin press-fitting sites are set apart from each other, as in a comparative structure in which the sensor lever is pivotally supported in the axial middle portion of the pin and both ends of the pin in the axial direction are press-fitted into the side wall of the housing. In such a structure, the relative positional relationship between the side walls is likely to greatly shift due to the press-fitting, but in the structure of the present embodiment, since the pin press-fitting site is not set to be largely separated, The shift due to the press-fitting is less likely to occur as compared with the contrast structure. As a result, in this embodiment, the axial direction of the pin 48 can be set with high accuracy.

  Further, the pin 48 is inserted into the pair of cylindrical portions 54 with respect to the press-fit portion 52, and the inner peripheral surface of the cylindrical portion 54 is formed by the press-fit ribs 58 provided between the pair of cylindrical portions 54. It is pressed to the upper surface 54A (see FIG. 4) side. For this reason, when the sensor lever 46 rotates and moves with the inertial movement of the ball 42, the vertical movement of the pin 48 at the press-fit portion 52 is suppressed.

  Furthermore, in the webbing take-up device 10 according to the present embodiment, the end portion in the axial direction of the pin 48 is formed with an inclined portion 48A inclined in a tapered manner toward the terminal side, so that FIG. When the pin 48 is press-fitted into the press-fit portion 52, after the tip side of the pin 48 passes through the first tubular portion 54, the inclined portion 48A of the pin 48 is pressed into the press-fit rib as shown in FIG. 58A, the inclined portion 48A gradually rides on the press-fitting rib 58. Next, as shown in FIG. 6C, when the inclined portion 48 </ b> A passes through the first press-fitting rib 58, the upper surface position of the pin 48 is changed to the inside of the first tubular portion 54 by the press-fit rib 58. It is brought close to the upper surface side of the peripheral surface. Then, when the pin 48 passes through the second press-fit rib 58 and further passes through the second cylindrical portion 54 on the outlet side of the press-fit portion 52 as shown in FIG. Is pressed against the upper surface 54A side of the inner peripheral surface of the pair of cylindrical portions 54. In other words, the pin 48 is sandwiched vertically by the press-fitting rib 58 and the upper surface 54A of the inner peripheral surface of the pair of cylindrical portions 54.

  Thus, the pin 48 is smoothly press-fitted into the press-fit portion 52 and positioned. That is, when the pins 48 are press-fitted, the resistance at the pair of cylindrical portions 54 that are both side portions in the axial direction of the press-fit portion 52 is suppressed, and therefore the relative positional relationship between the pair of cylindrical portions 54 is more difficult to shift.

  In addition, when supplemented from another viewpoint, if the pin (shaft member) is inserted into the pair of insertion portions so as to be relatively rotatable around the axis, the outer peripheral surface of the pin (shaft member) and the insertion portion If the size of the gap in the axial diameter direction between the inner peripheral surface and the inner peripheral surface is constant, as in the present embodiment, compared to a comparative configuration in which the insertion portion is on the inner side (positioned between the pair of press-fitting portions) The configuration in which the insertion portion 50 is located on the outer side in the axial direction with respect to the press-fit portion 52 can reduce the angle of inclination of the pin 48 (inclination angle with respect to the reference direction to be set) that can be generated by the gap.

  As described above, according to the webbing take-up device 10 according to the present embodiment, the sensor performance of the acceleration sensor 40 shown in FIG. 1 can be stabilized.

  In the present embodiment, the pin 48 has a structure that penetrates the insertion part 50 and the press-fitting part 52, so that, for example, the pin 48 is compared with a comparison structure in which the rotation shaft is integrated with the sensor lever in advance. It is easy to suppress the length in the axial direction. Supplementally, in the comparison structure in which the rotating shaft is integrated with the sensor lever in advance, the relative positional relationship between the pair of insertion portions on the housing side is not changed greatly when the sensor lever is assembled. May be formed of a cylindrical portion and the other insertion portion may be formed of a C-shaped portion opened upward. In such a structure, when the rotary shaft is assembled to the insertion portion, one of the rotation shafts is placed on one insertion portion side in a state where the axis direction of the rotation shaft is inclined with respect to the direction in which the pair of insertion portions are arranged. Insert the tip, and then change the attitude of the rotating shaft to fit the other end of the rotating shaft into the other insertion part, and assemble the sensor lever body integrated with the rotating shaft. Sometimes the posture changes. That is, in this structure, the length of the rotating shaft has to be set long in order to avoid interference between the sensor lever main body and the insertion portion forming portion during assembly. On the other hand, in this embodiment, since there is no such restriction, the length of the pin 48 in the axial direction is suppressed, and as a result, downsizing is facilitated as compared with the above-described comparison structure.

[Second Embodiment]
Next, a webbing take-up device according to a second embodiment of the present invention will be described with reference to FIGS. FIG. 8 is an exploded perspective view showing an upper portion of the acceleration sensor 72 in the webbing take-up device 70 according to the second embodiment of the present invention. Further, in FIG. 9, the upper part of the acceleration sensor 72 is shown in a longitudinal sectional view.

  As shown in these drawings, in the present embodiment, the upper portion of the acceleration sensor 72 is different from the upper portion of the acceleration sensor 40 (see FIGS. 3 and 4) according to the first embodiment. Other configurations are substantially the same as those of the first embodiment. Therefore, components that are substantially the same as those of the first embodiment are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIGS. 8 and 9, the sensor lever 76 is supported on the upper end portion of the housing 74 of the acceleration sensor 72 so as to be capable of rotating (swinging). A pin 48 serving as a rotational movement axis of the sensor lever 76 passes through the housing 74 and the sensor lever 76. More specifically, the base end portion of the sensor lever 76 is bifurcated to form a pair of insertion portions 80 that are provided slightly apart from each other, and the pair of insertion portions 80 are formed at both ends of the pin 48. The pin 48 is inserted in such a manner that it can rotate relative to its axis. In other words, the pair of insertion portions 80 function as pivoted portions that are rotatably supported by the pins 48. Further, the housing 74 is formed with a press-fit portion 82 disposed between the pair of insertion portions 80, and the pin 48 is press-fitted and fixed to the press-fit portion 82 (see FIG. 9).

  The press-fit portion 82 includes a pair of cylindrical portions 84 into which the pins 48 are inserted. The inner diameter of the cylindrical portion 84 is set slightly larger than the outer diameter of the pin 48. As shown in FIG. 8, the pair of cylindrical portions 84 are connected by a connecting portion 86, and the connecting portion 86 is formed with a groove portion 86 </ b> A continuous with the lower surface of the inner peripheral surface of the cylindrical portion 84. Yes. The groove portion 86 </ b> A extends in the connecting direction for connecting the cylindrical portions 84. In addition, a pair of press-fitting ribs 88 is formed in the connecting portion 86 at an intermediate portion in the extending direction of the groove portion 86A. The press-fitting rib 88 is formed so as to be orthogonal to the extending direction of the groove portion 86A in plan view, and the upper end surface presses the pin 48 against the upper surface 84A side of the inner peripheral surface of the cylindrical portion 84 as shown in FIG. It is set to the height position. In other words, the press-fit portion 82 includes a pair of cylindrical portions 84 and press-fit ribs 88.

  Also by the configuration of the present embodiment described above, the same operations and effects as those of the first embodiment described above can be obtained.

[Supplementary explanation of the embodiment]
In the above embodiment, the press-fit portions 52 and 82 include the cylindrical portions 54 and 84 and the press-fit ribs 58 and 88, and the press-fit ribs 58 and 88 connect the pin 48 to the upper surface of the inner peripheral surface of the cylindrical portions 54 and 84. 54A and 84A are pressed against each other, but the press-fitting part is formed, for example, in a pair of cylindrical parts into which a shaft member is inserted and a connecting part that connects between the pair of cylindrical parts. And a press-fitting rib that is pressed against the lower surface side of the inner peripheral surface of the cylindrical portion. Further, as a reference example that is not an embodiment of the present invention , the press-fitting portion is composed of a single or a plurality of cylindrical portions having an inner diameter that is substantially equal to the outer diameter of the shaft member (strictly, slightly larger). May be.

  Further, in the above-described embodiment, the end portion in the axial direction of the pin 48 is formed with the inclined portion 48A that is tapered toward the terminal side, and this configuration is the axial direction in the press-fit portions 52 and 82. The shaft member may be another shaft member such as a shaft member having a constant diameter.

10 Webbing take-up device 16 Spool 18 Webbing belt 20 Lock mechanism (locking means)
26 V gear (rotating body)
40 Acceleration sensor 42 Ball (Inertial body)
44 Housing 46 Sensor lever (lever)
48 pins (shaft member)
48A Inclined part 50 Inserting part 52 Press-in part 54 Cylindrical part 56 Connecting part 58 Press-in rib 70 Webbing take-up device 72 Acceleration sensor 74 Housing 76 Sensor lever (lever)
80 Insertion part 82 Press-fit part 84 Cylindrical part 86 Connection part 88 Press-fit rib

Claims (2)

A spool that is wound in layers in a webbing belt that is mounted on a vehicle occupant and that rotates in the pull-out direction when the webbing belt is pulled out;
A rotating body coaxially disposed on the shaft end side of the spool and coupled to the spool so as to follow and rotate;
An acceleration sensor that stops rotation of the rotating body in the pull-out direction by operating during sudden deceleration of the vehicle;
Lock means for operating the acceleration sensor to operate when a relative rotation occurs between the spool and the rotating body to lock the rotation of the spool in the pull-out direction;
The acceleration sensor has
An inertial body that moves inertially at an acceleration greater than a predetermined value;
A housing that supports the inertial body;
A lever that is pushed by the inertial movement of the inertial body to rotate and engages the rotation body and prevents the rotation of the rotation body in the pull-out direction;
A shaft member that penetrates the housing and the lever and serves as a rotational movement axis of the lever;
A pair of insertion parts formed on one of the lever and the housing and provided on both ends of the shaft member, the shaft member being inserted so as to be relatively rotatable about its axis;
A press-fit portion formed on the other of the lever and the housing and disposed between the pair of insertion portions, and the shaft member is press-fitted and fixed;
I have a,
The press-fitting portion is formed in a pair of cylindrical portions into which the shaft member is inserted and a connecting portion that connects the pair of cylindrical portions, and the shaft member is connected to the upper surface side of the inner peripheral surface of the cylindrical portion. Alternatively, a webbing take-up device comprising a press-fitting rib that is pressed against the lower surface side . The shaft in an end portion in the axial direction of the member, the webbing take-up device according to claim 1, wherein the inclined portion inclined in a tapered shape toward the terminal side.