Tilt sensor and seatbelt retractor

Abstract

Provided is a tilt sensor and a seat belt retractor that improve the assemblability of a wheel. The tilt sensor includes a rotating body that rotates by tilting of a seat back, and a wire that has a leading end portion connected to a seat belt retractor provided to the seat back, and a base end portion connected to the rotating body, wherein the rotating body rotates to wind the wire from the base end portion side, thereby pulling the wire toward the base end portion side, and the rotating body has an outer wheel that fixes the base end portion and winds the wire, an inner wheel that is housed inside the outer wheel and rotates integrally with the outer wheel, a position fixing mechanism that fixes the relative position of the outer wheel and the inner wheel in the rotation direction of the rotating body in a manner that allows adjustment of the relative position, and a movement restriction mechanism that restricts the relative movement of the outer wheel and the inner wheel in the axial direction of the rotating body when the relative position is shifted in the rotation direction.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to an inclination sensor and a seat belt retractor. BACKGROUND

[0002] Conventionally, a seat belt retractor is known, which causes a lock mechanism to act to stop rotation of a spool for retracting a seat belt when an acceleration greater than a predetermined value is applied in a horizontal direction. An acceleration sensor for detecting the acceleration has a sensor housing for accommodating a sensor weight that turns in a tilting direction due to the acceleration in the horizontal direction.

[0003] On the other hand, sometimes a seat belt retractor is assembled in a seat back. However, if the seat belt retractor is assembled in the seat back, the sensor housing can be inclined with tilting of the seat back, and the sensor weight can cause the lock mechanism to act to lock.

[0004] A cable retractor is known, which, in order to prevent such lock action, keeps the sensor housing horizontal regardless of the angle of inclination of the seat back by pulling a cable for rotating the sensor housing in accordance with tilting of the seat back (see, for example, Patent Document 1). Further, the cable retractor is also called an inclination sensor.

[0005] <Related Art Documents>

[0006] <Patent Documents>

[0007] Patent Document 1: Japanese Patent Application Publication No. 10-226312 SUMMARY

[0008] <Problems to be Solved by the Invention>

[0009] In the cable retractor of Patent Document 1, a retractor body of the cable is constituted by a first fixed ring for fixing a base end portion of a wire and winding the wire, and a second fixed ring accommodated inside the first fixed ring and rotating integrally with the first fixed ring.

[0010] In this way, the outer ring such as the first fixed ring and the inner ring such as the second fixed ring are assembled together with each other.

[0011] The present disclosure provides an inclination sensor and a seat belt retractor having the inclination sensor and capable of improving the assemblability of the outer ring and the inner ring.

[0012] <Means for Solving the Problems>

[0013] The present disclosure provides a tilt sensor, and a seat belt retractor having the tilt sensor. The tilt sensor includes a rotating body that rotates by tilting of a seat back, and a wire that has a leading end portion connected to a seat belt retractor provided to the seat back, and a base end portion connected to the rotating body, in which the rotating body rotates to wind the wire from the base end portion side to the wire, thereby pulling the wire to the base end portion side, the rotating body has an outer wheel that fixes the base end portion and winds the wire, an inner wheel that is housed inside the outer wheel and rotates integrally with the outer wheel, a position fixing mechanism that fixes a relative position of the outer wheel and the inner wheel in a rotational direction of the rotating body in a manner that the relative position is adjustable, and a movement restricting mechanism that restricts a relative movement of the outer wheel and the inner wheel in an axial direction of the rotating body when the relative position is shifted in the rotational direction.

[0014] <Effects of the Invention>

[0015] According to the present disclosure, it is possible to provide a tilt sensor and a seat belt retractor having the tilt sensor, which can improve the assemblability of the outer wheel and the inner wheel. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 is a schematic side view of a seat on which a seat belt retractor in one embodiment is mounted.

[0017] Figure 2 is a perspective view of a tilt sensor in the first embodiment.

[0018] Figure 3 is an exploded perspective view of the tilt sensor in the first embodiment.

[0019] Figure 4 is a perspective view of an outer wheel in the first embodiment.

[0020] Figure 5 is a front view of the outer wheel in the first embodiment.

[0021] Figure 6 is a back view of the outer wheel in the first embodiment.

[0022] Figure 7 is a perspective view of an inner wheel in the first embodiment.

[0023] Figure 8 is a front view of the inner wheel in the first embodiment.

[0024] Figure 9 is a back view of the inner wheel in the first embodiment.

[0025] Figure 10 is a front view partially enlarging the first state of the movement restriction mechanism in the first embodiment.

[0026] Figure 11 is a front view partially enlarging the second state of the movement restriction mechanism in the first embodiment.

[0027] Figure 12 is a back view partially enlarging the second state of the movement restriction mechanism in the first embodiment.

[0028] Figure 13 is a front view of the rotating body in the first embodiment.

[0029] Figure 14 is a back view of the rotating body in the first embodiment.

[0030] Figure 15 is a perspective view of the outer wheel in the second embodiment.

[0031] Figure 16 is a front view of the outer wheel in the second embodiment.

[0032] Figure 17 is a perspective view of the inner wheel in the second embodiment.

[0033] Figure 18 is a front view of the inner wheel in the second embodiment.

[0034] Figure 19 is a front view of the rotating body in the second embodiment. DETAILED DESCRIPTION

[0035] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that in the following description, the X-axis, the Y-axis, and the Z-axis are orthogonal to each other. The X-axis direction, the Y-axis direction, and the Z-axis direction each represent a direction parallel to the X-axis, a direction parallel to the Y-axis, and a direction parallel to the Z-axis, respectively. The XY plane, the YZ plane, and the ZX plane each represent a virtual plane including the X-axis and the Y-axis, a virtual plane including the Y-axis and the Z-axis, and a virtual plane including the Z-axis and the X-axis, respectively.

[0036] Figure 1 is a schematic side view of a seat on which the seat belt retractor device in one embodiment is mounted. Figure 1The illustrated seat belt retractor 10 is mounted on a seat 16 provided in a passenger compartment of a vehicle. The seat 16 has a seat cushion 12 that supports an occupant from below, and a seat back 14 that extends upward from a rear of the seat cushion 12. The seat 16 includes a reclining mechanism for tilting the seat back 14 about a reclining shaft 18 with respect to the seat cushion 12 in a forward tilting direction F or a rearward tilting direction R. An axial direction of the reclining shaft 18 is along a width direction of the seat 16. When the seat back 14 is tilted about the reclining shaft 18 with respect to the seat cushion 12, a seat belt retractor 100 provided on the seat back 14 is also tilted about the reclining shaft 18 with respect to the seat cushion 12.

[0037] The seat belt retractor 10 includes the seat belt retractor 100 and a reclining sensor 11.

[0038] The seat belt retractor 100 is a seat belt retractor that enables retraction or extraction of a seat belt that is not illustrated, and is fixed to a seat back frame that is not illustrated within the seat back 14. The seat belt retractor 100 includes a belt shaft 104 for retracting the seat belt, a lockup mechanism 103 for locking rotation of the belt shaft 104 in an extraction direction of the seat belt, and an acceleration sensor 102 for actuating the lockup mechanism 103. The acceleration sensor for actuating the lockup mechanism is also referred to as a vehicle sensor.

[0039] The acceleration sensor 102 has a sensor housing 101 for housing a sensor weight, a gear 105 for rotating the sensor housing 101 with respect to a sensor frame of the acceleration sensor 102, and a force applying mechanism 106 for applying a force to the wire 90 toward the front end portion 94 side of the wire 90. The force applying mechanism 106 applies a force to the wire 90 toward the front end portion 94 side of the wire 90 via the gear 105 by means of an elastic body such as a spring, for example.

[0040] The reclining sensor 11 is a mechanism that transmits a degree of tilting (tilting angle) of the seat back 14 to the sensor housing 101 of the acceleration sensor 102 of the seat belt retractor 100 via the wire 90 so as to maintain the sensor housing 101 horizontal. The wire 90 has a front end portion 94 connected to the seat belt retractor 100, and a base end portion 91 connected to the reclining sensor 11, and is spanned between the seat belt retractor 100 and the reclining sensor 11. The reclining sensor 11 transmits the degree of tilting of the seat back 14 to the sensor housing 101 of the acceleration sensor 102 by pulling the wire 90 by an amount corresponding to the degree of tilting, for example. The reclining sensor 11 is arranged coaxially with the reclining shaft 18 of the seat 16, and is fixed to a seat cushion frame that is not illustrated of the seat cushion 12.

[0041] Figure 2 is a perspective view of the reclining sensor in the first embodiment.Figure 3 is an exploded perspective view of the tilt sensor in the first embodiment. Figure 2 and Figure 3 The tilt sensor 11 shown in FIG. 1 1 includes a wheel cover 80, a rotating body 55, a wire 90, a cover plate 20, a bracket 30, and a press-in pin 79. The tilt sensor 11 has a structure in which the rotating body 55 is rotated to wind up the wire 90 from the base end portion 91 side with respect to the wire 90, thereby pulling the wire 90 toward the base end portion 91 side. The rotating body 55 is a member that combines the outer wheel 60 and the inner wheel 40.

[0042] Figure 4 is a perspective view of the outer wheel in the first embodiment. Figure 5 is a front view of the outer wheel in the first embodiment. Figure 6 is a back view of the outer wheel in the first embodiment. Figure 7 is a perspective view of the inner wheel in the first embodiment. Figure 8 is a front view of the inner wheel in the first embodiment. Figure 9 is a back view of the inner wheel in the first embodiment.

[0043] Next, each part of the tilt sensor of the first embodiment will be described with appropriate reference to Figures 1 to 9 .

[0044] The wheel cover 80 is a housing-like member that supports the outer wheel 60 and the inner wheel 40. The wheel cover 80 has a plate-like bottom wall 89 in which the thickness direction (the X-axis direction in this example) is along the width direction of the seat 16, and a peripheral wall 88 that protrudes from the outer peripheral portion of the bottom wall 89 to one side of the thickness direction of the bottom wall 89 (the negative side in the X-axis direction in this example). The wheel cover 80 is open in the thickness direction of the bottom wall 89, and accommodates the outer wheel 60 and the inner wheel 40 at the opening portion. The thickness direction of the bottom wall 89 is along the axial direction of the tilt axis 18 (see FIG. 1 1). Figure 1 .

[0045] The wheel cover 80 has a circular hole 81 formed in the central portion of the bottom wall 89, and a cylindrical portion 84 that is cylindrical and has an inner diameter substantially equal to that of the circular hole 81 and is formed on the same axis as the circular hole 81. The cylindrical portion 84 is provided inside the peripheral wall 88 and protrudes from the periphery of the circular hole 81 to one side of the thickness direction of the bottom wall 89. The center axes of the circular hole 81 and the cylindrical portion 84 are on the same axis as the tilt axis 18. The tilt axis 18 is inserted into the circular hole 81 and the cylindrical portion 84 from the positive side of the X-axis direction.

[0046] The rotating body 55 is a member that combines the outer wheel 60 and the inner wheel 40 into one body and rotates by tilting of the seatback 14. The rotating body 55 has the outer wheel 60 on which the base end portion 91 of the wire 90 is fixed and which winds the wire 90, and the inner wheel 40 that is housed inside the outer wheel 60 and rotates integrally with the outer wheel 60.

[0047] The outer wheel 60 and the inner wheel 40 are rotating members that are disposed inside the wheel cover 80. The outer wheel 60 and the inner wheel 40 are annular plates whose thickness direction is along the X-axis direction. The outer wheel 60 has an outer wheel hole 61 for housing the inner wheel 40, and the inner wheel 40 has an inner wheel hole 41 whose inner diameter dimension is slightly larger than the outer shape dimension of the cylindrical portion 84. The outer wheel hole 61 is a circular hole that penetrates the outer wheel 60 in the X-axis direction, and the inner wheel hole 41 is a circular hole that penetrates the inner wheel 40 in the X-axis direction. The respective center axes of the outer wheel hole 61 and the inner wheel hole 41 are on the same axis as the tilt axis 18. The tilt axis 18 penetrates the inner wheel hole 41 from the positive side of the X-axis direction. The rotating body 55 that combines the outer wheel 60 and the inner wheel 40 into one body rotates with the cylindrical portion 84 as the center in a state where the tilt axis 18 penetrates the inner wheel hole 41.

[0048] On the outer peripheral surface 64 of the outer wheel 60, a wire fixing portion 65 for fixing the base end portion 91 of the wire 90 and a wire guide portion 63 for guiding the wire 90 whose base end portion 91 is fixed by the wire fixing portion 65 are formed. For example, the wire fixing portion 65 is a groove that is recessed with respect to the outer peripheral surface 64 of the outer wheel 60, and the base end portion 91 of the wire 90 is hooked on the wire fixing portion 65 to be fixed and connected. The wire 90 whose base end portion 91 is fixed by the wire fixing portion 65 is wound on the wire guide portion 63 along the outer peripheral surface 64.

[0049] The wire guide portion 63 has drop prevention pieces 66a, 66b (see FIG. 6) that protrude outward from the outer wheel 60 in the radial direction of the outer wheel 60 from both sides in the axial direction (in this example, the X-axis direction) of the outer wheel 60 on the outer peripheral surface 64. By winding the wire 90 on the wire guide portion 63 in a state where the wire 90 is sandwiched between the drop prevention pieces 66a, 66b on both sides, the wire 90 is prevented from dropping off the wire guide portion 63 of the outer peripheral surface 64. Figures 3 to 6 ). By winding the wire 90 on the wire guide portion 63 in a state where the wire 90 is sandwiched between the drop prevention pieces 66a, 66b on both sides, the wire 90 is prevented from dropping off the wire guide portion 63 of the outer peripheral surface 64.

[0050] In the wire 90, the base end portion 91 is fixed to the outer wheel 60, and the front end portion 94 is fixed to the acceleration sensor 102 (see FIG. 6). The wire 90 is wound on the outer wheel 60 in a state where the base end portion 91 is fixed to the outer wheel 60 and the front end portion 94 is fixed to the acceleration sensor 102. Figure 3 In the wire 90, the base end portion 91 is fixed to the outer wheel 60, and the front end portion 94 is fixed to the acceleration sensor 102 (see FIG. 6). The wire 90 is wound on the outer wheel 60 in a state where the base end portion 91 is fixed to the outer wheel 60 and the front end portion 94 is fixed to the acceleration sensor 102. Figure 1The fixing device 92 is fixed to the pipe fixing portion 85 formed on the wheel cover 80.

[0051] The pipe fixing portion 85 is a site for fixing the pipe base end portion of the pipe 93, and is formed on a portion of the peripheral wall 88 of the wheel cover 80. The pipe fixing portion 85 has, for example, a fixing groove 86 formed at a portion of the peripheral wall 88. The pipe fixing portion 85 fixes the pipe base end portion of the pipe 93 by hooking the fixing device 92 at the fixing groove 86, to prevent the pipe base end portion from coming off the wheel cover 80.

[0052] The pipe front end portion of the pipe 93 is fixed to the sensor frame of the acceleration sensor 102 by the fixing device 95. The sensor frame of the acceleration sensor 102 is fixed to the frame of the seat belt retractor 100. The front end portion 94 of the wire 90 is fixed to a gear 105 (see Figure 1 ) that rotates the sensor housing 101 relative to the sensor frame of the acceleration sensor 102.

[0053] The rotation of the gear 105 rotates the sensor housing 101 relative to the sensor frame of the acceleration sensor 102 by moving the front end portion 94 of the wire 90 toward the base end portion 91 side.

[0054] The cover plate 20 is a cover provided on the opening side of the wheel cover 80. The cover plate 20 has a plate-shaped cover portion 26 whose thickness direction is along the X-axis direction, and the cover portion 26 is fixed to the peripheral wall 88 of the wheel cover 80. The cover plate 20 has an opening 21 formed at a central portion of the cover portion 26, a plurality of holes 22a, 22b, 22c, 22d formed in the cover portion 26 around the opening 21, and mounting arms 24, 25 extending from a portion of the outer periphery of the cover portion 26. The inclined shaft 18 that passes through the circular hole 81 and the cylindrical portion 84 of the wheel cover 80 from the positive side of the X-axis direction passes through the opening 21 from the positive side of the X-axis direction.

[0055] The wheel cover 80 has a plurality of bosses 87a, 87b, 87c, 87d at positions corresponding to each of the plurality of holes 22a, 22b, 22c, 22d of the cover plate 20. The cover plate 20 is fixed to the wheel cover 80 by fastening a plurality of fastening members such as screws 23a, 23b, 23c, 23d that pass through each of the plurality of holes 22a, 22b, 22c, 22d to the plurality of bosses 87a, 87b, 87c, 87d.

[0056] The bracket 30 has a fixed plate 34 sandwiched between the cover portion 26 of the cover plate 20 and the rotating body 55 for combining the inner wheel 40 and the outer wheel 60 into one. The fixed plate 34 is a plate-like portion in the thickness direction along the X-axis direction. The bracket 30 has a central hole 31 formed at the center of the fixed plate 34, and a mounting leg 32 protruding from a portion of the outer periphery of the fixed plate 34. The inclined shaft 18 passing through the circular hole 81 and the cylindrical portion 84 of the wheel cover 80 from the positive side in the X-axis direction passes through the central hole 31 from the positive side in the X-axis direction.

[0057] The front end portion of the mounting leg 32 of the bracket 30 is fixed to the seat cushion 12 (for example, the seat cushion frame of the seat cushion 12). On the other hand, the front end portions of the mounting arms 24, 25 of the cover plate 20 fixed to the wheel cover 80 are fixed to the seat back 14 (for example, the seat back frame of the seat back 14). Thus, when the seat back 14 is tilted with respect to the seat cushion 12 about the inclined shaft 18, the wheel cover 80 is rotated with respect to the bracket 30 about the inclined shaft 18.

[0058] The bracket 30 has a stopper pin 33 protruding from the fixed plate 34 toward the inner wheel 40 side (the positive side in the X-axis direction in this example). The inner wheel 40 has a slit 42 for insertion of the stopper pin 33. The slit 42 is a circular arc-shaped groove or through-hole with the axis of the inner wheel 40 as the center. The slit 42 has a slit start end 44 as the slit end on the forward tilt direction F side, and a slit end termination 45 as the slit end on the rearward tilt direction R side. On the other hand, the wheel cover 80 has a tab 82 protruding from the bottom wall 89 toward the inner wheel 40 side (the negative side in the X-axis direction in this example). The inner wheel 40 has a slit 43 for insertion of the tab 82. The slit 43 is a circular arc-shaped groove or through-hole with the axis of the inner wheel 40 as the center. The slit 43 has a slit start end 46 as the slit end on the forward tilt direction F side, and a slit end termination 47 as the slit end on the rearward tilt direction R side.

[0059] As described above, the wire 90 is always subjected to the force application mechanism 106 to apply a force toward the front end portion 94 side in the length direction thereof. Therefore, since the rotating body 55 is always subjected to a force in the rearward tilt direction R, the stopper pin 33 abuts against the slit start end 44 on the forward tilt direction F side of the slit 42. Therefore, when the wheel cover 80 integrated with the seat back 14 is rotated in the rearward tilt direction R, and the rotating body 55 attempts to rotate in the rearward tilt direction R together with the wheel cover 80, the rotation of the rotating body 55 in the rearward tilt direction R is restricted. The reason for this is that the stopper pin 33 formed on the bracket 30 integrated with the seat cushion 12 abuts against the slit start end 44 of the slit 42. Therefore, when the wheel cover 80 relatively rotates with respect to the rotating body 55 in the rearward tilt direction R, the rotating body 55 causes the base end portion 91 of the wire 90 in the length direction to be pulled and moved.

[0060] On the other hand, since the rotating body 55 is always forced in the backward tilt direction R, the tab 82 abuts against the slit start end 46 on the forward tilt direction F side of the slit 43. In the state where the tab 82 abuts against the slit start end 46 of the slit 43, the wheel cover 80 rotates in the forward tilt direction F together with the rotating body 55. Thereby, the stopper pin 33 of the bracket 30 relatively moves in the slit 42 in such a manner that it moves away from the slit start end 44 and approaches the slit end end 45 on the opposite side to the slit start end 44.

[0061] Next, the movement of the tilt sensor 11 and the movement of the seat belt retractor 100 due to the difference in the tilt direction of the seat back 14 will be described.

[0062] In the seat belt retractor 10, when the seat back 14 is tilted in such a manner that the upper end side of the seat back 14 is tilted toward the rear of the seat 16, the wheel cover 80 fixed to the seat back frame of the seat back 14 rotates in the backward tilt direction R from the state shown in the drawing. In contrast to this, since the mounting leg 32 of the bracket 30 of the tilt sensor 11 is fixed to the seat cushion frame of the seat cushion 12, the bracket 30 does not rotate even if the seat back 14 is tilted. Therefore, in this state, the wheel cover 80 relatively rotates in the backward tilt direction R with respect to the bracket 30. Figure 2

[0063] In this state, when the rotating body 55 attempts to rotate together with the wheel cover 80, the stopper pin 33 of the bracket 30 interferes with the slit start end 44 of the slit 42, thereby restricting the rotation of the rotating body 55 in the backward tilt direction R. Therefore, in this state, the wheel cover 80 relatively rotates in the backward tilt direction R with respect to the rotating body 55.

[0064] On the pipe fixing portion 85 of the wheel cover 80, the fixing means 92 provided at the base end portion of the pipe 93 in the length direction of the pipe 93 is fixed, and on the wire fixing portion 65 of the rotating body 55, the base end portion 91 of the wire 90 in the length direction of the wire 90 is fixed. Therefore, when the wheel cover 80 relatively rotates in the backward tilt direction R with respect to the rotating body 55, the wire 90 moves to the base end portion side in the length direction thereof on the inside of the pipe 93 against the force of the force applying mechanism 106 of the acceleration sensor 102.

[0065] ​Thus, in the acceleration sensor 102, the front end portion 94 of the wire 90 in the length direction thereof moves toward the base end portion side, and the gear 105 to which the front end portion 94 of the wire 90 is fixed rotates. Due to the rotation of the gear 105, the sensor housing 101 rotates with respect to the sensor frame of the acceleration sensor 102 in a manner to cancel the tilting of the seatback 14 (tilting of the sensor frame). In this way, by rotating the sensor housing 101 with respect to the sensor frame, the sensor housing 101 is maintained in the original posture before the tilting. Thus, even if the seatbelt retractor 100 tilts in the rearward tilting direction R together with the seatback 14, it is possible to prevent the sensor weight from being moved unintentionally (the vehicle is not suddenly decelerated as it is). Therefore, as long as the acceleration sensor 102 is not subjected to an acceleration of a predetermined value or more, it is possible to prevent the erroneous operation of the lock mechanism 103 due to the movement of the sensor weight, and it is possible to prevent the rotation of the belt shaft 104 from being unintentionally locked.

[0066] On the other hand, in a case where the upper end side of the seatback 14 is tilted toward the front of the seat 16 to fold the seat 16, the wheel cover 80 rotates in the forward tilting direction F together with the seatback 14. When the wheel cover 80 rotates in this manner, since the inner wheel 40 is pressed on the tab 82 of the wheel cover 80 by the slit start end 46, the rotating body 55 rotates in the forward tilting direction F together with the wheel cover 80. When such rotation in the forward tilting direction F occurs in the wheel cover 80, since the interval between the wire fixing portion 65 of the rotating body 55 and the tube fixing portion 85 of the wheel cover 80 does not change, the wire 90 is not pulled toward the base end portion 91 side. Thus, the gear 105 of the acceleration sensor 102 and the sensor housing 101 do not rotate.

[0067] In this way, since the tilt sensor 11 does not move in conjunction with the seat tilting in the forward tilting direction F, the sensor housing 101 tilts forward together with the seatbelt retractor 100. Since the acceleration sensor 102 does not hold the sensor housing 101 horizontally, the sensor weight can move in a direction to activate the lock mechanism 103. However, since the seatbelt retractor 100 has a known lock release mechanism for impeding the activation of the lock mechanism 103, the rotation of the belt shaft 104 is not impeded. Thus, it is possible to prevent the seatbelt from being locked and caught when the seatback 14 is tilted forward or lifted up.

[0068] In addition, in a case where the rotating body 55 rotates in the forward tilting direction F together with the wheel cover 80, the stopper pin 33 of the bracket 30 relatively moves away from the slit start end 44 toward the slit end end 45 with respect to the slit 42. Therefore, even if the wheel cover 80 and the rotating body 55 rotate in the forward tilting direction F, the rotating body 55 does not unintentionally interfere with the bracket 30 fixed to the seat cushion 12, but it is possible to smoothly tilt the seatback 14 toward the front of the seat 16.

[0069] Further, the wheel cover 80 has holes 83 (holes 83a, 83b) for position alignment formed on the bottom wall 89, and the inner wheel 40 has holes 49 (holes 49a, 49b) for position alignment formed at positions corresponding to the holes 83a, 83b. These holes 83, 49 are used to insert a tool for position alignment of both when assembling the tilt sensor 11.

[0070] The rotating body 55 has a position fixing mechanism 56 that fixes the relative position (rotational phase) of the outer wheel 60 in the rotational direction (circumferential direction) of the rotating body 55 and the inner wheel 40 in such a manner that the relative position can be adjusted to an arbitrary position. In this example, the position fixing mechanism 56 has an inner tooth 62 provided on a portion of the inner peripheral surface 68 of the outer wheel 60, and an outer tooth 48 provided on a portion of the outer peripheral surface 51 of the inner wheel 40. The position fixing mechanism 56 fixes the relative position of the outer wheel 60 in the rotational direction of the rotating body 55 and the inner wheel 40 by engaging the inner tooth 62 with the outer tooth 48.

[0071] The rotating body 55 that winds the wire 90 has two rings (the outer wheel 60 and the inner wheel 40). The reason for using two rings in this way to constitute the rotating body 55 is that even if the distance between the seat belt retractor 100 and the tilt sensor 11 differs due to individual differences of the vehicle or the seat, etc., the wire 90 is stretched without slack between the two in an appropriate length. The outer wheel 60 is rotated in such a manner that the slack of the wire 90 between the seat belt retractor 100 and the tilt sensor 11 is reduced, and the inner tooth 62 of the outer wheel 60 is engaged with the outer tooth 48 of the inner wheel 40 at the engagement position where the slack is reduced.

[0072] The position fixing mechanism 56 has a press-in pin 79 that fixes the inner tooth 62 and the outer tooth 48 in a state where the inner tooth 62 is engaged with the outer tooth 48 by being press-fitted into the pin hole 52 formed at the inner wheel 40. By the press-in pin 79, the effect of suppressing the shift of the relative position of the outer wheel 60 in the rotational direction (circumferential direction) of the rotating body 55 and the inner wheel 40 can be improved.

[0073] The rotating body 55 has a movement restricting mechanism 57 that restricts the relative movement of the outer wheel 60 and the inner wheel 40 in the axial direction (thrust direction) of the rotating body 55 by shifting the relative position of the outer wheel 60 in the rotational direction (circumferential direction) of the rotating body 55 and the inner wheel 40 in the rotational direction. By restricting the relative movement of the outer wheel 60 and the inner wheel 40 in the axial direction of the rotating body 55 with the movement restricting mechanism 57, it is possible to prevent the outer wheel 60 and the inner wheel 40 from coming off each other in the axial direction. In this way, the assemblability between the outer wheel 60 and the inner wheel 40 can be improved.

[0074] The movement restriction mechanism 57 in the first embodiment has a plurality of recesses 69a, 69b, 69c and a plurality of ledges 67a, 67b, 67c, 70a, 70b, 70c provided on the outer wheel 60, and a plurality of protrusions 50a, 50b, 50c provided on the inner wheel 40.

[0075] The plurality of recesses 69a, 69b, 69c are provided on the inner circumferential surface 68 of the outer wheel 60 at intervals in the circumferential direction from each other, and are recessed from the inner circumferential surface 68 toward the outer side in the radial direction of the outer wheel 60.

[0076] The plurality of ledges 70a, 70b, 70c are provided on the inner circumferential surface 68 of the outer wheel 60 at intervals in the circumferential direction from each other, and are adjacent to the plurality of recesses 69a, 69b, 69c in the circumferential direction. The plurality of ledges 70a, 70b, 70c are each an example of a first ledge, and protrude from the inner circumferential surface 68 toward the inner side in the radial direction of the outer wheel 60.

[0077] The plurality of ledges 67a, 67b, 67c are provided on the inner circumferential surface 68 of the outer wheel 60 at intervals in the circumferential direction from each other, and are adjacent to the plurality of recesses 69a, 69b, 69c in the circumferential direction. The plurality of ledges 67a, 67b, 67c are each an example of a second ledge, and protrude from the inner circumferential surface 68 toward the inner side in the radial direction of the outer wheel 60. The inner wheel 40 is sandwiched in the axial direction of the outer wheel 60 between the plurality of ledges 70a, 70b, 70c and the plurality of ledges 67a, 67b, 67c.

[0078] The plurality of protrusions 50a, 50b, 50c are provided on the outer circumferential surface 51 of the inner wheel 40 at intervals in the circumferential direction from each other, and are claw-like portions protruding from the outer circumferential surface 51 toward the outer side in the radial direction of the inner wheel 40.

[0079] Reference Signs List Figures 10 to 12 The function of the movement restriction mechanism 57 in the first embodiment will be described. Figure 10 is a front view partially enlargedly showing the first state of the movement restriction mechanism in the first embodiment. Figure 11 is a front view partially enlargedly showing the second state of the movement restriction mechanism in the first embodiment. Figure 12 is a back view partially enlargedly showing the second state of the movement restriction mechanism in the first embodiment.

[0080] In Figure 10The outer wheel 60 and the inner wheel 40 are assembled in such a manner that each position of the protrusions 50 (50a, 50b, 50c) matches each position of the respective corresponding recesses 69 (69a, 69b, 69c). Flanges 67a, 67b, 67c are provided on the inner circumferential surface 68 of the outer wheel 60. Therefore, even if the inner wheel 40 is caused to enter the outer wheel hole 61 of the outer wheel 60 from the negative side in the X-axis direction, the outer circumferential portion of the inner wheel 40 is hooked by the flanges 67a, 67b, 67c. Thus, the inner wheel 40 can be prevented from escaping through the outer wheel hole 61 at the time of assembly.

[0081] Next, as shown in FIG. 6, the relative positions in the circumferential direction of the inner wheel 40 and the outer wheel 60 are offset. In the example shown in FIG. 6, the inner wheel 40 is fixed, and the outer wheel 60 is rotated in the counterclockwise direction. For example, the inner wheel 40 is fixed, and the outer wheel 60 is rotated in the counterclockwise direction by causing a tool to enter the position alignment holes 49a, 49b of the inner wheel 40 from the position alignment holes 83a, 83b of the wheel cover 80. When the inner wheel 40 and the outer wheel 60 are caused to rotate relative to each other, since the outer teeth 48 are pressed from the inner teeth 62 toward the inner side in the radial direction, the outer teeth 48 are bent toward the inner side in the radial direction in such a manner that the space of the pin hole 52 is narrowed, allowing the relative rotation of the inner wheel 40 and the outer wheel 60. Figure 11 Figure 11 Next, as shown in FIG. 6, the relative positions in the circumferential direction of the inner wheel 40 and the outer wheel 60 are offset. In the example shown in FIG. 6, the inner wheel 40 is fixed, and the outer wheel 60 is rotated in the counterclockwise direction. For example, the inner wheel 40 is fixed, and the outer wheel 60 is rotated in the counterclockwise direction by causing a tool to enter the position alignment holes 49a, 49b of the inner wheel 40 from the position alignment holes 83a, 83b of the wheel cover 80. When the inner wheel 40 and the outer wheel 60 are caused to rotate relative to each other, since the outer teeth 48 are pressed from the inner teeth 62 toward the inner side in the radial direction, the outer teeth 48 are bent toward the inner side in the radial direction in such a manner that the space of the pin hole 52 is narrowed, allowing the relative rotation of the inner wheel 40 and the outer wheel 60.

[0082] When the relative positions in the circumferential direction of the inner wheel 40 and the outer wheel 60 are offset as shown in FIG. 7, the protrusions 50 (50a, 50b, 50c) are engaged with the flanges 70 (70a, 70b, 70c) (see FIG. 8). Thus, by abutting the outer circumferential portion of the inner wheel 40 against the flanges 67a, 67b, 67c of the outer wheel 60, movement of the inner wheel 40 to the positive side in the X-axis direction is restricted. On the other hand, by abutting the protrusions 50a, 50b, 50c against the flanges 70a, 70b, 70c, movement of the inner wheel 40 to the negative side in the X-axis direction is restricted. Therefore, as shown in FIG. 7 and FIG. 8, the inner wheel 40 and the outer wheel 60 are integrated. Figure 11 Figure 12 Figure 13 Figure 14 Figure 13 is a front view of the rotating body in the first embodiment. Figure 14 is a back view of the rotating body in the first embodiment. Note that in Figure 13 , Figure 14 , the illustration of the press-in pin 79 is omitted.

[0083] ​​​​​As described above, the movement restriction mechanism 57 in the first embodiment restricts movement in the axial direction of the protrusions 50a, 50b, 50c that are offset in the rotation direction from the recesses 69a, 69b, 69c by the flanges 70a, 70b, 70c. Thereby, it is possible to prevent the inner ring 40 and the outer ring 60 from coming off in the axial direction.

[0084] Next, the tilt sensor in the second embodiment will be described. The second embodiment differs from the first embodiment in the structure of the inner ring and the outer ring. As for the same points between the first embodiment and the second embodiment, the above description is cited to omit repeated description.

[0085] Figure 15 is a perspective view of the outer ring in the second embodiment. Figure 16 is a front view of the outer ring in the second embodiment. Figure 17 is a perspective view of the inner ring in the second embodiment. Figure 18 is a front view of the inner ring in the second embodiment. Figure 19 is a front view of the rotating body in the second embodiment.

[0086] In the second embodiment shown in FIG. 17, the difference from the first embodiment is that the recesses and the first flanges adjacent to the recesses are provided on the outer circumferential surface of the inner ring, and the protrusions corresponding to the recesses are provided on the inner circumferential surface of the outer ring. Figures 15 to 19

[0087] When the relative positions of the outer ring 160 and the inner ring 140 in the rotation direction (circumferential direction) of the rotating body 55 are offset in the rotation direction, the movement restriction mechanism 57 in the second embodiment restricts relative movement of the outer ring 160 and the inner ring 140 in the axial direction (thrust direction) of the rotating body 55. By restricting relative movement of the outer ring 160 and the inner ring 140 in the axial direction of the rotating body 55 with the movement restriction mechanism 57, it is possible to prevent the outer ring 160 and the inner ring 140 from coming off each other in the axial direction. In this way, it is possible to improve the assemblability between the outer ring 160 and the inner ring 140.

[0088] The movement restriction mechanism 57 in the second embodiment has a plurality of recesses 169a, 169b, 169c and a plurality of flanges 170a, 170b, 170c provided on the inner ring 140, and a plurality of protrusions 150a, 150b, 150c provided on the outer ring 160.

[0089] The plurality of recesses 169a, 169b, 169c are portions that are provided at intervals in the circumferential direction from each other on the outer circumferential surface 51 of the inner ring 140, and are recessed toward the inside in the radial direction of the inner ring 140 from the outer circumferential surface 51.

[0090] ​The plurality of flanges 170a, 170b, 170c are provided on the outer circumferential surface 51 of the inner ring 140 at positions spaced apart from each other in the circumferential direction, and are adjacent to the plurality of recesses 169a, 169b, 169c in the circumferential direction. The plurality of flanges 170a, 170b, 170c are each an example of the first flange.

[0091] The plurality of flanges 67a, 67b, 67c are provided on the inner circumferential surface 68 of the outer ring 160 at positions spaced apart from each other in the circumferential direction. The plurality of flanges 67a, 67b, 67c are each an example of the second flange, and protrude from the inner circumferential surface 68 toward the inner side in the radial direction of the outer ring 160. The inner ring 140 is sandwiched in the axial direction of the outer ring 160 between the plurality of protrusions 150a, 150b, 150c and the plurality of flanges 67a, 67b, 67c.

[0092] The plurality of protrusions 150a, 150b, 150c are claw-like portions provided on the inner circumferential surface 68 of the outer ring 160 at positions spaced apart from each other in the circumferential direction, and protrude from the inner circumferential surface 68 toward the inner side in the radial direction of the outer ring 160.

[0093] In the Figure 19 , the outer ring 160 and the inner ring 140 are assembled in such a manner that the positions of the protrusions 150 (150a, 150b, 150c) match the positions of the recesses 169 (169a, 169b, 169c) corresponding thereto, respectively.

[0094] Next, the relative positions in the circumferential direction of the inner ring 140 and the outer ring 160 are shifted. In the Figure 19 example shown, the inner ring 140 is fixed, and the outer ring 160 is rotated in the counterclockwise direction. When the relative positions in the circumferential direction of the inner ring 140 and the outer ring 160 are shifted, the protrusions 150 (150a, 150b, 150c) engage with the flanges 170 (170a, 170b, 170c) (since the positions of the protrusions 150 (150a, 150b, 150c) match the positions of the flanges 170 (170a, 170b, 170c) corresponding thereto, respectively, due to the Figure 12 same, the illustration is omitted). Thereby, the movement of the inner ring 140 to the positive side in the X-axis direction is restricted by abutting the outer circumferential portion of the inner ring 140 against the flanges 67a, 67b, 67c of the outer ring 160. On the other hand, the movement of the inner ring 140 to the negative side in the X-axis direction is restricted by abutting the protrusions 150a, 150b, 150c against the flanges 170a, 170b, 170c. Thus, the inner ring 140 and the outer ring 160 are integrated (since the positions of the protrusions 150 (150a, 150b, 150c) match the positions of the flanges 170 (170a, 170b, 170c) corresponding thereto, respectively, due to the Figure 13 and Figure 14 same, the illustration is omitted).

[0095] As described above, the movement restriction mechanism 57 in the second embodiment restricts movement in the axial direction of the protrusions 150a, 150b, 150c that are offset from the recesses 169a, 169b, 169c in the rotation direction by the flanges 170a, 170b, 170c. Thereby, the inner wheel 140 and the outer wheel 160 can be prevented from coming off in the axial direction.

[0096] Although the tilt sensor and the seat belt retractor have been described above through the embodiments, the present application is not limited to the above-described embodiments. Various modifications and improvements such as combination or replacement of a part or all of other embodiments can be made within the scope of the present application.

[0097] Symbol Explanation

[0098] 10 Seat belt retractor

[0099] 11 Tilt sensor

[0100] 12 Seat cushion

[0101] 14 Seat back

[0102] 16 Seat

[0103] 18 Tilt axis

[0104] 20 Cover plate

[0105] 23a, 23b, 23c, 23d Screw

[0106] 24, 25 Mounting arm

[0107] 26 Cover portion

[0108] 30 Bracket

[0109] 31 Central hole

[0110] 32 Mounting leg

[0111] 33 Stop pin

[0112] 34 Fixing plate

[0113] 40 Inner wheel

[0114] 41 Inner wheel hole

[0115] 42, 43 Slit

[0116] 48 Outer tooth

[0117] 50a, 50b, 50c Protrusion

[0118] 51 Outer peripheral surface

[0119] 52 Tapped hole

[0120] 55 rotating body

[0121] 56 position fixing mechanism

[0122] 57 movement restricting mechanism

[0123] 60 outer wheel

[0124] 61 outer wheel hole

[0125] 62 inner teeth

[0126] 63 wire guide

[0127] 64 outer peripheral surface

[0128] 65 wire fixing portion

[0129] 66a, 66b drop prevention piece

[0130] 67a, 67b, 67c flange (inner edge protrusion)

[0131] 68 inner peripheral surface

[0132] 69a, 69b, 69c recess

[0133] 70a, 70b, 70c flange

[0134] 79 press-in pin

[0135] 80 wheel cover

[0136] 81 circular hole

[0137] 82 tab

[0138] 83a, 83b hole

[0139] 84 tubular portion

[0140] 85 tube fixing portion

[0141] 86 fixing groove

[0142] 87a, 87b, 87c, 87d boss

[0143] 88 peripheral wall

[0144] 89 bottom wall

[0145] 90 wire

[0146] 91 base end portion

[0147] 92, 95 fixing device

[0148] 93 tube

[0149] 94 front end portion

[0150] 100 seat belt retractor

[0151] 101 sensor housing

[0152] 102 acceleration sensor

[0153] 103 lock mechanism

[0154] 104 belt shaft

[0155] 105 gear

[0156] 106 force applying mechanism

Claims

1. A tilt sensor comprising: a rotating body that rotates by tilting of a seat back; and a wire having a leading end portion connected to a seat belt retractor provided to the seat back, and a base end portion connected to the rotating body, wherein the wire is reeled in from the base end portion side by rotating the rotating body to cause the rotating body to reel in the wire from the base end portion side, thereby pulling the wire toward the base end portion side, the rotating body has: an outer wheel for fixing the base end portion and winding the wire; an inner wheel housed inside the outer wheel and rotating integrally with the outer wheel; a position fixing mechanism that fixes the relative position of the outer wheel and the inner wheel in the rotation direction of the rotating body in a manner that allows adjustment of the relative position; and a movement restricting mechanism having a first flange protruding in a radial direction from an inner peripheral surface of the outer wheel, a second flange protruding in a radial direction from the inner peripheral surface of the outer wheel, and a protrusion protruding in a radial direction from an outer peripheral surface of the inner wheel, and restricting movement of the inner wheel in the axial direction by causing the protrusion of the inner wheel to enter inside the outer wheel in the axial direction of the rotating body in a manner that matches the position of the protrusion to the position of a recess provided on the first flange, thereby restricting movement of the inner wheel in the axial direction between the first flange and the second flange in the rotation direction.

2. The tilt sensor according to claim 1, wherein the movement restricting mechanism restricts movement of the inner wheel in a first direction parallel to the axial direction by the second flange, and restricts movement of the inner wheel in a second direction opposite to the first direction by the first flange.

3. The tilt sensor according to claim 2, wherein the movement restricting mechanism restricts movement of the inner wheel in the first direction by abutting the outer peripheral portion of the inner wheel against the second flange, and restricts movement of the inner wheel in the second direction by abutting the protrusion against the first flange.

4. A tilt sensor comprising: a rotating body that rotates by tilting of a seat back; and a wire having a leading end portion connected to a seat belt retractor provided to the seat back, and a base end portion connected to the rotating body, wherein the wire is reeled in from the base end portion side by rotating the rotating body to cause the rotating body to reel in the wire from the base end portion side, thereby pulling the wire toward the base end portion side, the rotating body has: an outer wheel for fixing the base end portion and winding the wire; an inner wheel housed inside the outer wheel and rotating integrally with the outer wheel; a position fixing mechanism that fixes the relative position of the outer wheel and the inner wheel in the rotation direction of the rotating body in a manner that allows adjustment of the relative position; and a movement restricting mechanism having a first flange protruding in a radial direction from an inner peripheral surface of the outer wheel, a second flange protruding in a radial direction from the inner peripheral surface of the outer wheel, and a protrusion protruding in a radial direction from an outer peripheral surface of the inner wheel, and restricting movement of the inner wheel in the axial direction by causing the protrusion of the inner wheel to enter inside the outer wheel in the axial direction of the rotating body in a manner that matches the position of the protrusion to the position of a recess provided on the first flange, thereby restricting movement of the inner wheel in the axial direction between the first flange and the second flange in the rotation direction. The movement restriction mechanism has a first flange protruding in a radial direction from an outer peripheral surface of the inner wheel, a second flange protruding in a radial direction from an inner peripheral surface of the outer wheel, and a projection protruding in a radial direction from the inner peripheral surface of the outer wheel, and restricts movement of the inner wheel in the axial direction by moving the first flange of the inner wheel, which enters into an inner side of the outer wheel in an axial direction of the rotating body in a manner that a position of the projection matches a position of a recess provided on the first flange, in the rotational direction between the projection and the second flange.

5. The tilt sensor according to claim 4, wherein The movement restriction mechanism restricts movement of the inner wheel in a first direction parallel to the axial direction by the second flange, and restricts movement of the inner wheel in a second direction opposite to the first direction by the projection.

6. The tilt sensor according to claim 5, wherein The movement restriction mechanism restricts movement of the inner wheel in the first direction by abutting the outer peripheral portion of the inner wheel against the second flange, and restricts movement of the inner wheel in the second direction by abutting the projection against the first flange.

7. The tilt sensor according to any one of claims 1 to 6, wherein The position fixation mechanism has an inner tooth provided on a portion of the inner peripheral surface of the outer wheel, and an outer tooth provided on a portion of the outer peripheral surface of the inner wheel, and fixes the relative position by engaging the inner tooth with the outer tooth.

8. The tilt sensor according to claim 7, wherein The position fixation mechanism has a press-in pin that fixes the inner tooth and the outer tooth in a state where the inner tooth is engaged with the outer tooth by being pressed into the inner wheel.

9. A safety belt retractor comprising: The tilt sensor according to any one of claims 1 to 8; and The safety belt retractor.

Images