JP2013159319A - Seat belt device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tongue extraction auxiliary function by utilizing a motor of a winding device.SOLUTION: A seat belt device 10 includes an arm 60, and a transmission mechanism 20 and the arm 60 are coupled by a belt clutch 42. When a motor 18 rotates in a reverse direction, rotation of the motor 18 is transmitted to the arm 60 by the belt clutch 42, and the arm 60 moves a tongue 32 upward from an initial position. The belt clutch 42 prevents forward rotation of the motor 18 from being transmitted to the arm 60, thereby preventing the rotation of the motor 18 from being transmitted to the arm 60 when the motor 18 rotates in the forward direction during vehicle collision prediction. Accordingly, a webbing 28 can be wound up by the drive of the motor 18, while reducing an influence of the arm 60 during the vehicle collision prediction. The tongue extraction auxiliary function can be obtained by utilizing the motor 18 of a lap-side winding device 12.

Description

  The present invention relates to a seat belt device including a winding device having a motor.

  Some seat belt devices include a retractor having a so-called pre-crash function that winds a seat belt (webbing) by driving a motor in a vehicle emergency (when a vehicle collision is predicted, for example) (for example, , See Patent Document 1 below).

  Some seat belt devices include a tongue extraction assist device (see, for example, Patent Document 2 below). In this tongue extraction assisting device, one end of a lever arranged on the outer side in the vehicle width direction of the seat is connected to a screw shaft, and a motor is connected to the screw shaft. The other end of the lever is in contact with the seat belt. When the motor rotates in one direction of rotation, the lever is moved forward and upward from the retracted position, and the tongue provided on the seat belt is moved forward and upward. Thereby, the seated occupant can easily grip the tongue provided on the seat belt.

JP 2007-160986 A JP 2007-30528 A

  By the way, the winding device and the tongue extraction assisting device are usually arranged adjacent to each other. For this reason, it is desirable to share the motor for the winding device and the motor for the tongue extraction assisting device.

  In view of the above facts, an object of the present invention is to provide a seat belt device capable of realizing a tongue take-out assist function using a motor of a take-up device.

  The seat belt device according to claim 1 has a transmission mechanism that transmits the rotation of the motor to a spool for winding the webbing by rotating in the winding direction, and the motor moves in the forward rotation direction when a vehicle collision is predicted. A winding device that winds the webbing by connecting the transmission mechanism and the spool when rotated; a tongue that is provided on the webbing and disposed at an initial position when the webbing is not mounted; and the motor A moving member that moves the tongue upward from an initial position by rotating in the reverse direction, and the transmission mechanism and the moving member are connected, and the rotation of the motor in the reverse direction is transmitted to the moving member. A clutch that blocks transmission of rotation to the moving member in the forward rotation direction of the motor.

  In the seat belt device according to the first aspect, the winding device includes a transmission mechanism and a motor. For example, when the vehicle predicts a collision (when an obstacle is present in front of the vehicle while the vehicle is running and the distance from the vehicle to the obstacle is below a reference value), the motor is rotated in the forward direction. By doing so, the transmission mechanism and the spool are connected, and the rotation of the motor is transmitted to the spool. Thus, the webbing is wound around the spool by rotating the spool in the winding direction. For this reason, since the restraining force of the webbing with respect to a passenger | crew can be improved at the time of a vehicle collision prediction, what is called a pre-crash function can be provided to a seatbelt apparatus.

  Here, the seat belt device includes a moving member, and the moving member is connected to the transmission mechanism by a clutch. When the motor rotates in the reverse rotation direction, the rotation of the motor in the reverse rotation direction is transmitted to the moving member by the clutch, and the moving member moves the tongue upward from the initial position. As a result, the dung is moved to a position where it is easy for the occupant to grip, so that a so-called tongue extraction assist function can be provided to the seat belt device.

  Moreover, since the clutch blocks the rotation transmission to the moving member in the forward direction of the motor, when the motor rotates in the forward direction at the time of vehicle collision prediction, the rotation transmission to the moving member of the motor is blocked. The Thereby, at the time of vehicle collision prediction, the webbing can be wound by driving the motor while suppressing the influence of the moving member, and the restraining force of the webbing on the occupant can be improved.

  The seatbelt device according to claim 2 is the seatbelt device according to claim 1, wherein when the motor rotates in the reverse rotation direction, the winding device connects the transmission mechanism and the spool. Rotate the spool in the pull-out direction.

  In the seat belt device according to claim 2, when the motor rotates in the reverse rotation direction, the transmission mechanism and the spool are connected and the spool is rotated in the pull-out direction, so that the moving member moves the tongue upward from the initial position. The operating load of the moving member when moving to can be reduced.

  That is, normally, since the urging force in the winding direction is applied to the spool by an urging spring or the like, the moving member moves the tongue against this urging force by rotating the spool in the pulling direction. Can be suppressed.

  The seat belt device according to claim 3, wherein the clutch is connected to the transmission mechanism and has a ratchet-like engagement portion on an outer peripheral portion thereof. A belt having a body, a driven rotator provided on a side of the main rotating body, and an engaged portion that is wound around the main rotating body and the driven rotating body and engageable with the engaging portion. And one end of the moving member is inserted into the webbing and made contactable with the tongue, and the other end of the moving member is fixed to the belt.

  In the seatbelt device according to the third aspect, the clutch includes a main rotating body connected to the transmission mechanism. A ratchet-like engagement portion is formed on the outer peripheral portion of the main rotating body. A driven rotator is provided on the side of the main rotating body, and a belt is wound around the main rotating body and the driven rotating body. Thereby, when the motor rotates, the main rotating body rotates, and the belt and the driven rotating body rotate as the main rotating body rotates.

  The belt has an engaged portion, and the engaged portion can be engaged with the engaging portion. Thereby, when the motor rotates in the forward rotation direction, it is configured to release the engagement between the ratchet-shaped engaging portion and the engaged portion, thereby slipping between the motor and the belt, The belt can be configured not to rotate.

  Here, one end of the moving member is inserted into the webbing so as to be in contact with the tongue, and the other end of the moving member is fixed to the belt. Accordingly, since the moving member moves as the belt rotates, the moving distance and moving direction of the moving member can be easily determined depending on the distance between the driven rotating body and the driven rotating body and the position of the driven rotating body with respect to the driven rotating body. Can be set to

  According to the seat belt device of the first aspect, the tongue take-out assist function can be realized by using the motor of the winding device.

  According to the seat belt device of the second aspect, the operating load of the moving member when the moving member moves the tongue upward from the initial position can be reduced.

  According to the seat belt device of the third aspect, the moving distance and moving direction of the moving member can be easily set.

It is the side view seen from the vehicle left side which shows the principal part of the seatbelt apparatus which concerns on embodiment of this invention. It is the front view seen from the vehicle front which shows the whole seatbelt apparatus shown by FIG. FIG. 3 is an enlarged front view of a tongue extraction assisting mechanism used in the seat belt device shown in FIG. 2 as viewed from the front of the vehicle. (A)-(C) are explanatory drawings for demonstrating the movement from the initial position of the arm shown by FIG.

  FIG. 2 is a front view of the entire seat belt device 10 according to the embodiment of the present invention as viewed from the front of the vehicle. Note that an arrow FR appropriately shown in the drawings indicates the front of the vehicle, an arrow OUT indicates the outer side in the vehicle width direction, and an arrow UP indicates the upper side.

  As shown in this figure, the seat belt device 10 is configured to restrain a lap side winding device 12 as a “winding device” for restraining mainly the waist of the seated occupant and the upper body mainly for the seated occupant. The shoulder side winding device 22, the webbing 28 for restraining the upper body and waist of the seated occupant, and the tongue take-out assist mechanism 40 are configured. And the seatbelt apparatus 10 is provided in the vehicle width direction outer side of the seat S of a vehicle.

  The lap side winding device 12 is provided on the vehicle width direction outer side of the seat cushion SC of the seat S on which the occupant is seated. As shown in FIG. 1, the wrap side winding device 12 includes a wrap side frame (hereinafter referred to as “L side frame”) 14, and the L side frame 14 is an inner side in the vehicle width direction as viewed from above. It is formed in a substantially U shape that is open to the back. The lap side winding device 12 is fixed to the vehicle body by fixing the L side frame 14 to the vehicle body.

  A lap side spool (hereinafter referred to as “L side spool”) 16 as a “spool” is provided inside the L side frame 14. The L-side spool 16 is formed in a substantially cylindrical shape as a whole, and is rotatably supported by the L-side frame 14 with the axial direction as the vehicle longitudinal direction. A base end portion of a webbing 28 described later is connected and fixed to the L-side spool 16. Then, when the L-side spool 16 is rotated in the winding direction (the direction of arrow A in FIG. 3), the webbing 28 is wound around the outer peripheral portion of the L-side spool 16 from its own base end side. When pulling from the front end side, the webbing 28 is pulled out while the L-side spool 16 rotates in the pulling-out direction (arrow B direction in FIG. 3).

  The L-side spool 16 is connected to a lap-side biasing spring (hereinafter referred to as “L-side biasing spring”) (not shown). The L-side biasing spring is configured as a mainspring spring, and the L-side biasing spring biases the L-side spool 16 in the winding direction.

  A motor 18 is provided below the L-side spool 16, and the motor 18 is fixed to the L-side frame 14 with the axial direction being the vehicle front-rear direction. The motor 18 is electrically connected to the control unit 74 of the vehicle, and a current is supplied to the motor 18 by the control unit 74 so that the motor 18 is rotated in the forward direction or the reverse direction. .

  A transmission mechanism 20 is provided on the front side of the L-side frame 14. The transmission mechanism 20 is configured as a reduction gear train composed of a plurality of gears, and connects the motor 18 and the L-side spool 16 via a transmission clutch described later.

  Further, a transmission clutch (not shown) is provided between the transmission mechanism 20 and the L-side spool 16, and this transmission clutch is a conventionally known so-called centrifugal clutch. Here, the transmission clutch will be briefly described. The transmission clutch has a gear clutch that meshes with the gear of the transmission mechanism 20. Further, the gear clutch is provided with a pawl so as to be rotatable, and the pawl is engaged with a ratchet provided on the shaft portion of the L-side spool 16 by rotating the gear clutch in one direction of rotation. It is configured. Thereby, it is comprised so that the transmission mechanism 20 and the L side spool 16 may be connected by the transmission clutch.

  In the present embodiment, the transmission mechanism 20 and the L-side spool 16 are coupled by rotating the transmission clutch in the forward rotation direction. That is, when the motor 18 rotates in the forward rotation direction, the transmission mechanism 20 and the L-side spool 16 are connected by the transmission clutch, and the L-side spool 16 rotates in the winding direction. On the other hand, when the motor 18 rotates in the reverse rotation direction, the transmission clutch does not connect the transmission mechanism 20 and the L-side spool 16. Thus, the transmission clutch is configured as a so-called one-way clutch.

  As shown in FIG. 2, the shoulder side winding device 22 is provided on the vehicle rear side of the lap side winding device 12, and the shoulder side winding device 22 is fixed to the vehicle body. Similar to the wrap side winding device 12, the shoulder side winding device 22 includes a shoulder side frame (hereinafter referred to as “S side frame”) 24 and a shoulder side spool rotatably supported by the S side frame 24. (Hereinafter referred to as “S-side spool”) 26 (not shown) and a shoulder-side biasing spring (not shown) that biases the S-side spool 26 in the winding direction (hereinafter referred to as “S-side biasing spring”). And.

  And the front-end | tip part of the webbing 28 mentioned later is connected and fixed to the S side spool 26, and when the S side spool 26 rotates in the winding direction, the webbing 28 is wound around the outer peripheral part of the S side spool 26, By pulling the webbing 28, the S-side spool 26 is rotated in the pull-out direction, and the webbing 28 is pulled out.

  The webbing 28 is formed in a long band shape. The webbing 28 extends upward from the lap side winding device 12, is folded downward by a shoulder anchor 70 of the vehicle, and extends to the shoulder side winding device 22. Further, the webbing 28 is inserted into the insertion hole 34 of the tongue 32 and is sewn so as to be fixed to the tongue 32 at an intermediate portion in the longitudinal direction of the webbing 28 (see FIGS. 1 and 3). Accordingly, the webbing 28 includes a lap side webbing part (hereinafter referred to as “L side webbing part”) 28A mainly restraining the waist part of the seated occupant and a shoulder side webbing part (hereinafter referred to as “L side webbing part”) mainly restraining the upper body. 28B) (referred to as “S-side webbing portion”).

  Further, since the biasing force of the S-side biasing spring is set to be weaker than the biasing force of the L-side biasing spring described above, the tongue 32 is not mounted when the webbing 28 is not mounted on the seated occupant. Is disposed on the wrap side winding device 12 side (the position shown in FIG. 1, and this position is referred to as “initial position”).

  Next, the configuration of the tongue extraction assist mechanism 40 will be described. As shown in FIGS. 1 and 3, the tongue take-out assist mechanism 40 is configured to include a belt clutch 42 as a “clutch” and an arm 60 as a “moving member”. A main driving sprocket 44 as a “main rotating body”, a driven sprocket 48 as a “following rotating body”, and a timing belt 52 as a “belt” are configured.

  The main sprocket 44 is formed in a substantially disc shape and is provided on the front side of the lap side winding device 12 in the vehicle. Further, the main sprocket 44 is disposed such that its axial direction is parallel to the axial direction of the L-side spool 16 and is supported directly or indirectly on the L-side frame 14 of the wrap-side winding device 12. Further, the main sprocket 44 is connected to the transmission mechanism 20 so that the rotation of the motor 18 is transmitted to the main sprocket 44 via the transmission mechanism 20. That is, the rotation of the motor 18 is transmitted to the transmission clutch and the main sprocket 44 by the transmission mechanism 20. When the motor 18 is rotated in the forward direction, the main drive sprocket 44 is rotated in the winding direction (the direction of arrow A in FIG. 3). When the motor 18 is rotated in the reverse direction, the main drive sprocket 44 is rotated. The sprocket 44 is rotated in the drawing direction (the direction of arrow B in FIG. 3).

  A plurality of engaging convex portions 46 as “engaging portions” are formed on the outer peripheral portion of the main sprocket 44. The engaging convex portion 46 is formed in a ratchet shape in a front view and protrudes outward in the radial direction of the main sprocket 44.

  The driven sprocket 48 is formed in a substantially disc shape and has a smaller diameter than the main sprocket 44. The driven sprocket 48 is arranged on the lower side of the main sprocket 44 with the axial direction parallel to the axial direction of the main sprocket 44, and is attached to the L side frame 14 of the wrap side winding device 12 via a bracket (not shown). And is rotatably supported.

  A plurality of fitting convex portions 50 are formed on the outer peripheral portion of the driven sprocket 48. The fitting convex portion 50 is formed in a substantially rectangular shape when viewed from the front, protrudes radially outward of the driven sprocket 48, and is curved along the circumferential direction of the driven sprocket 48.

  The timing belt 52 is formed in an endless shape, and is wound around the outer peripheral portions of the main driving sprocket 44 and the driven sprocket 48. As a result, the timing belt 52 is wound around a long, substantially track shape whose longitudinal direction is the vertical direction when viewed from the front. The timing belt 52 is provided with a plurality of engagement holes 54 as “engaged portions”, and the engagement holes 54 are arranged along the circumferential direction of the timing belt 52. In this engagement hole 54, the engagement convex part 46 and the fitting convex part 50 are each arrange | positioned.

  Here, when the motor 18 rotates in the forward rotation direction and the main sprocket 44 rotates in the winding direction (arrow A direction in FIG. 3), the engagement convex portion 46 formed in a ratchet shape is engaged. Tension is acting on the timing belt 52 so as to leave the hole 54. That is, in this case, the timing belt 52 is configured not to rotate in the winding direction (the direction indicated by the arrow C in FIG. 3) by slipping between the outer peripheral portion of the main sprocket 44 and the inner peripheral portion of the timing belt 52. Has been.

  On the other hand, when the main sprocket 44 rotates in the pull-out direction (arrow B direction in FIG. 3) by rotating the motor 18 in the reverse rotation direction, the engagement between the engagement convex portion 46 and the engagement hole 54 The timing belt 52 rotates in the pull-out direction (arrow D direction in FIG. 3), and the driven sprocket 48 moves in the pull-out direction (arrow E direction in FIG. 3) due to the engagement between the engagement hole 54 and the fitting convex portion 50. It is configured to rotate.

  A holder 56 for supporting an arm 60 described later is fixed to the outer peripheral portion of the timing belt 52. Thereby, the holder 56 moves with the rotation of the timing belt 52, and the movement trajectory of the holder 56 has a substantially track shape. The holder 56 is disposed at the lower end of the timing belt 52 at the initial position.

  Further, a position detection sensor 58 (an element grasped as “detection means” in a broad sense) is provided below the driven sprocket 48, and the position detection sensor 58 is provided on the lap side winding device 12. The L-side frame 14 is fixed via the bracket (not shown) described above. The position detection sensor 58 is electrically connected to the above-described vehicle control unit 74 and configured to detect the position of the holder 56 at the initial position.

  The arm 60 is formed in a substantially long rod shape and is disposed on the vehicle front side of the belt clutch 42. An abutting portion 62 is provided at one end of the arm 60, and the abutting portion 62 is formed in a substantially track-shaped annular shape. The L-side webbing portion 28A of the webbing 28 is inserted into the contact portion 62, so that the contact portion 62 is movable along the longitudinal direction of the L-side webbing portion 28A. The contact portion 62 is disposed closer to the lap side winding device 12 than the tongue 32, and the contact portion 62 and the tongue 32 are in contact with each other at the initial position.

  The other end of the arm 60 is rotatably supported by the above-described holder 56, whereby the arm 60 and the transmission mechanism 20 of the lap side winding device 12 are connected by the belt clutch 42. In addition, since the holder 56 is disposed at the lower end of the timing belt 52 at the initial position, the arm 60 extends upward from the lower end of the timing belt 52.

  On the other hand, as shown in FIG. 2, a buckle device 72 is provided inside the seat S in the vehicle width direction, and the buckle device 72 is fixed to the floor of the vehicle. A buckle switch (not shown) is provided in the buckle device 72, and the buckle switch is electrically connected to a control unit 74 of the vehicle. When the tongue 32 is attached to the buckle device 72, a signal is output from the buckle switch to the control unit 74.

  Further, a seating sensor 78 is provided in the seat cushion SC of the seat S, and the seating sensor 78 is electrically connected to the control unit 74 of the vehicle. When the occupant is seated on the seat S, a signal is output from the seating sensor 78 to the control unit 74. Further, an obstacle detection sensor 76 is provided at the front of the vehicle. The obstacle detection sensor 76 is configured to be able to detect the distance from the vehicle to an obstacle ahead of the vehicle, for example, and is configured to output the detected signal to the control unit 74. Based on the signal output from the obstacle detection sensor 76 to the control unit 74, the control unit 74 controls the supply of current to the motor 18.

  Next, the operation and effect of the present invention will be described.

  In the seat belt device 10 having the above-described configuration, when the webbing 28 is not attached to the occupant, the webbing 28 extends upward from the wrap side winding device 12 and the tongue 32 is disposed at the initial position. (See FIG. 4A). When the occupant sits on the seat cushion SC of the seat S in this state, a signal is output from the seating sensor 78 to the control unit 74, and the control unit 74 of the vehicle detects that the occupant is seated on the seat S.

  When the control unit 74 detects that the occupant is seated on the seat S, the control unit 74 supplies a current to the motor 18 to rotate the motor 18 in the reverse direction. When the motor 18 is rotated in the reverse direction, the rotation of the motor 18 is transmitted to the main drive sprocket 44 via the transmission mechanism 20, and the main drive sprocket 44 is pulled out (in the direction of arrow B in FIGS. 3 and 4A). ). At this time, since the rotation of the motor 18 is in the reverse direction, the transmission clutch of the lap side winding device 12 does not connect the transmission mechanism 20 and the L side spool 16.

  The timing belt 52 is rotated in the pull-out direction (the direction indicated by the arrow D in FIGS. 3 and 4B) by the engagement of the engagement convex portion 46 of the main sprocket 44 and the engagement hole 54 of the timing belt 52. At the same time, the driven sprocket 48 is rotated in the pull-out direction (the direction of arrow E in FIGS. 3 and 4B) by fitting the engagement hole 54 with the fitting convex portion 50 of the driven sprocket 48. As a result, the holder 56 is moved upward from the lower end of the timing belt 52, so that the entire arm 60 is moved upward (see FIG. 4B).

  When the entire arm 60 is moved upward, the tongue 32 is moved upward by the contact portion 62 of the arm 60. And the control part 74 of a vehicle measures the energization time of the electric current to the motor 18, and stops the supply of the electric current to the motor 18 when the arm 60 (holder 56) reaches the upper end of the timing belt 52. As a result, the arm 60 is stopped at the upper end of the timing belt 52 (see FIG. 4C). Thereby, since the passenger | crew can hold | grip the tongue 32 arrange | positioned above an initial position, the seatbelt apparatus 10 can have what is called a tongue extraction assistance function.

  Then, the occupant grasps the tongue 32 disposed above the initial position, and pulls out the webbing 28 from the lap side winding device 12 and the shoulder side winding device 22 and hangs around the upper body and waist of the occupant. Further, when the tongue 32 is attached to the buckle device 72, the webbing 28 is attached to the upper body and waist of the occupant, and a signal is output from the buckle switch to the control unit 74 of the vehicle.

  When a signal is output from the buckle switch to the control unit 74 of the vehicle, the control unit 74 supplies a current to the motor 18 and the motor 18 is rotated again in the reverse direction. As a result, the rotation of the motor 18 in the reverse direction is transmitted to the main sprocket 44 via the transmission mechanism, the main sprocket 44 rotates in the pull-out direction, and the timing belt 52 rotates in the pull-out direction. As a result, the holder 56 and the arm 60 move downward from the upper end of the timing belt 52.

  When the holder 56 reaches the initial position, the position detection sensor 58 detects the holder 56, and a signal is output from the position detection sensor 58 to the control unit 74. As a result, the supply of current to the motor 18 is stopped by the controller 74, and the arm 60 is stopped at the initial position.

  On the other hand, at the time of vehicle collision prediction (when an obstacle is present in front of the vehicle while the vehicle is running and the distance from the vehicle to the obstacle is below a reference value), the controller 74 causes a current to flow to the motor 18. When supplied, the motor 18 is rotated in the forward rotation direction. As a result, the rotation of the motor 18 is transmitted to the transmission mechanism 20 of the lap side winding device 12, and the transmission clutch connects the transmission mechanism 20 and the L-side spool 16.

  When the transmission mechanism and the L-side spool 16 are connected, the L-side spool 16 rotates in the winding direction, so that the webbing 28 is wound around the L-side spool 16. Thereby, since the restraining force of the webbing 28 with respect to the passenger | crew at the time of the collision prediction of a vehicle is improved, the seatbelt apparatus 10 can have what is called a pre-crash function.

  By the way, at the time of a vehicle collision prediction, since the motor 18 is rotated in the forward direction, the main sprocket 44 is rotated in the winding direction (the direction of arrow A in FIG. 3). At this time, the engagement convex portion 46 of the main sprocket 44 is disengaged from the engagement hole 54 and slips between the outer peripheral portion of the main sprocket 44 and the inner peripheral portion of the timing belt 52, so that the timing belt 52 does not rotate in the winding direction (the direction of arrow C in FIG. 3). Therefore, the influence by the movement of the arm 60 at the time of vehicle collision prediction is suppressed.

  Further, in order to release the engagement between the pawl of the transmission clutch and the ratchet of the L-side spool 16, the motor 18 is rotated in the reverse direction. In this case, since the time for rotating the motor 18 in the reverse rotation direction is set to be relatively short, also in this case, the influence due to the movement of the arm 60 is suppressed.

  Here, as described above, the seat belt device 10 includes the arm 60, and the transmission mechanism 20 and the arm 60 are connected by the belt clutch 42. As the motor 18 rotates in the reverse direction, the rotation of the motor 18 in the reverse direction is transmitted to the arm 60 by the belt clutch 42, and the arm 60 moves the tongue 32 upward from the initial position. As a result, the dang 32 can be moved to a position that is easily gripped by the occupant, so that the seat belt device 10 can be provided with a so-called tongue extraction assist function.

  In addition, since the belt clutch 42 interrupts transmission of rotation of the motor 18 to the arm 60 in the forward rotation direction, when the motor 18 rotates in the forward rotation direction at the time of vehicle collision prediction, the belt clutch 42 rotates in the forward rotation direction of the motor 18. The rotation transmission to the arm 60 is interrupted. Thereby, at the time of a vehicle collision prediction, the webbing 28 is wound up by driving the motor 18 while suppressing the influence of the arm 60, and the restraining force of the webbing 28 on the occupant can be improved.

  As described above, the tongue take-out assist function can be realized by using the motor 18 of the lap side winding device 12.

  A driven sprocket 48 is disposed on the lower side of the main sprocket 44, and the timing belt 52 is wound around the main sprocket 44 and the driven sprocket 48. As a result, the timing belt 52 is wound around a long, substantially track shape whose longitudinal direction is the vertical direction when viewed from the front. Therefore, the moving distance and moving direction of the arm 60 can be easily set according to the distance between the main driving sprocket 44 and the driven sprocket 48 and the position of the driven sprocket 48 relative to the main driving sprocket 44.

  In the present embodiment, the transmission clutch is configured as a so-called one-way clutch. Alternatively, when the motor 18 rotates in the reverse direction, the transmission clutch may be configured as a conventionally known so-called bidirectional clutch that connects the transmission mechanism 20 and the L-side spool 16. In this case, for example, a pawl that operates when the transmission clutch rotates in the reverse rotation direction may be provided on the clutch gear so as to be rotatable. Thus, when the motor 18 rotates in the reverse direction, the pawl engages with the shaft portion of the L-side spool 16 so that the L-side spool 16 is rotated in the pull-out direction. For this reason, the operating load of the arm 60 when the arm 60 moves the tongue 32 upward from the initial position can be reduced. That is, by rotating the L-side spool 16 in the pull-out direction, it is possible to suppress the arm 60 from moving the tongue 32 against the urging force of the L-side urging spring.

  In this case, a speed reduction mechanism is provided between the belt clutch 42 and the transmission mechanism 20, and the speed at which the arm 60 is moved upward compared to the speed at which the webbing 28 is pulled out from the L-side spool 16. May be set to slow down. Thereby, the operating load of the arm 60 when the arm 60 moves the tongue 32 from the initial position to the upper side can be reliably reduced.

  Further, in the present embodiment, the L-side spool 16 is disposed with the axial direction set in the vehicle front-rear direction, and the axial direction of the main sprocket 44 is disposed in parallel with the axial direction of the L-side spool 16. Instead of this, the axial directions of the L-side spool 16, the main sprocket 44, and the driven sprocket 48 may be arranged so as to be inclined slightly toward the front of the vehicle as viewed from the left of the vehicle. Thus, the arm 60 can move the tongue 32 upward from the initial position and forward of the vehicle.

  In the present embodiment, a belt clutch 42 is provided between the arm 60 and the transmission mechanism 20. Instead, another clutch is provided between the belt clutch 42 and the transmission mechanism 20 so that when the motor 18 rotates in the reverse direction, the belt clutch 42 and the transmission mechanism 20 are connected by the clutch. It may be configured. In this case, the shape of the engaging convex portion 46 can be the same as the shape of the fitting convex portion.

  Further, in the present embodiment, the webbing 28 is configured to be fixed to the tongue 32. Alternatively, the webbing 28 may be configured to be inserted into the insertion hole 34 of the tongue 32, and a tongue stopper may be provided on the webbing 28 so that the tongue 32 is disposed at the initial position.

10 Seat belt device 12 Wrap side winding device (winding device)
16 Lap side spool (spool)
18 Motor 20 Transmission mechanism 28 Webbing 32 Tongue 42 Belt clutch (clutch)
44 Main sprocket (main rotating body)
46 Engagement convex part (engagement part)
48 Driven sprocket (driven rotor)
52 Timing Belt (Belt)
54 Engagement hole (engaged part)
60 arm (moving member)

Claims (3)

It has a transmission mechanism that transmits the rotation of the motor to the spool that winds the webbing by rotating in the winding direction, and when the motor rotates in the forward direction at the time of vehicle collision prediction, the transmission mechanism and the spool A winding device connected to wind up the webbing;
A tongue provided on the webbing and disposed at an initial position in a non-mounted state of the webbing;
A moving member that moves the tongue upward from an initial position by rotating the motor in a reverse direction;
A clutch for connecting the transmission mechanism and the moving member, transmitting rotation of the motor in the reverse rotation direction to the moving member, and blocking transmission of rotation of the motor in the normal rotation direction to the moving member;
A seat belt device comprising:   The seat belt device according to claim 1, wherein when the motor rotates in the reverse rotation direction, the winding device connects the transmission mechanism and the spool to rotate the spool in the pull-out direction. The clutch is
A main rotating body coupled to the transmission mechanism and having a ratchet-like engagement portion on an outer peripheral portion;
A driven rotor provided on a side of the main rotor,
A belt having an engaged portion that is wound around the main rotating body and the driven rotating body and engageable with the engaging portion;
With
3. The seat belt device according to claim 1, wherein one end portion of the moving member is inserted into the webbing and is brought into contact with the tongue, and the other end portion of the moving member is fixed to the belt. .

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