JP5332036B2 - Seat belt retractor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact retractor for a seat belt capable of preventing the occurrence of an end lock by erroneous operation of a webbing acceleration sensing means and a lock member itself of an emergency lock mechanism. <P>SOLUTION: In this retractor for the seat belt, a WS lever 50 of the webbing acceleration sensing means is controlled so as to be held in a first nonoperational position of not checking rotation in the webbing extracting direction of a steering wheel 40 when completing winding of a webbing by a control plate 80. The WS lever 50 prevents a rotational delay in the steering wheel 40 to a spindle 1 by being held in the first nonoperational position when completing the winding of the webbing, and holds a lock dog 20 in a lock releasing position of not engaging with a frame 10. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to an improvement in a seat belt retractor including an emergency lock mechanism (ELR) and an automatic lock mechanism (ALR).

Conventionally, as a seat belt retractor for safely holding an occupant or the like of a vehicle in a seat, an emergency lock mechanism that physically locks a webbing drawer by a vehicle body acceleration sensing means that reacts to sudden acceleration, collision or deceleration is provided. Therefore, an emergency lock type retractor that effectively and safely restrains an occupant is used.
Also, as a seat belt retractor for fixing child seats to vehicle seats with seat belts, it operates when all the webbing is pulled out, prevents webbing from being pulled out during winding, and deactivates when all the webbing is wound A device equipped with an automatic locking mechanism is used.

  By the way, in the seatbelt retractor provided with the emergency lock mechanism, the rotation of the spindle (winding shaft) in the webbing pull-out direction may be locked even when it is not necessary in the event of a vehicle emergency. That is, when the entire amount of webbing is suddenly taken up in accordance with the spring force of the take-up spring from the webbing pulled-out state when the vehicle is mounted, the emergency lock mechanism is activated by the impact and the rotation of the spindle in the webbing pull-out direction is locked. In this case, the webbing cannot be pulled out. In addition, since the webbing is fully wound up at this time, the spindle cannot rotate in the webbing winding direction, and the retractor falls into a so-called end-locked state.

  For example, there are the following emergency locking mechanisms. One is to detect the sudden withdrawal of the webbing and prevent the spindle from rotating in the webbing withdrawal direction (webbing acceleration sensing means: WS), and the other is to sense the sudden deceleration of the vehicle and to pull the spindle webbing. This is one that prevents rotation in the direction (vehicle body acceleration sensing means: VSI). In either case, the lock member that rotates integrally with the spindle is rocked so that the claw of the lock member meshes with the inner teeth of the frame that supports the spindle to lock the spindle (for example, Patent Document 1). And 2).

There are the following three cases where such an end lock occurs.
(1) Due to malfunction of webbing acceleration sensing means (WS).
In general, the webbing acceleration sensor means that when the belt is pulled out rapidly, the rotation of the mass side is delayed from the spindle due to the inertia of the mass, so that the lock member pops out and bites into the inner teeth of the frame Is used. However, if the webbing is stretched after the webbing is taken up suddenly, the mass is moved relative to the spindle with momentum, and the lock member is engaged with the inner teeth of the frame.
(2) Due to malfunction of vehicle body acceleration sensing means (VSI).
This is a case where when the acceleration is inputted to the vehicle body acceleration sensing means due to the rapid winding of the webbing, the ball as the inertia member moves, the lever swings, and the lever is rocked to be engaged with the latch member.
(3) Due to malfunction of the lock member itself.
This is a case where the lock member itself bites into the internal teeth of the frame with the momentum of winding the webbing.

  The seat belt retractor described in Patent Document 1 guides a cam follower provided on a rocking prevention member in a cam groove of a cam plate that is interlocked with the rotation of a spindle, and rotates a stopper portion of the rocking prevention member. And this stopper part contact | abuts to an inertial body, hold | maintains an inertial body in a non-operation position, and prevents a rocking | fluctuation of an inertial body. As a result, when the webbing winding is completed, the inertial body operates to prevent engagement with the lock gear (ratchet wheel), and end-locking when the webbing winding is completed is prevented.

  Further, the seat belt retractor described in Patent Document 2 has a cam member that is rotated by a planetary gear mechanism, and the lock wheel provided with a pair of lock plates as a lock means is fully wound with the spindle. End lock prevention means for preventing relative rotation is provided. Further, the seat belt retractor constitutes an automatic lock mechanism by rotating another cam member via a gear of the planetary gear mechanism and another gear.

JP-A-9-58410 Japanese Patent Laid-Open No. 10-129417

  By the way, in the seatbelt retractor described in Patent Document 1, the end lock due to the malfunction of the webbing acceleration sensing means is prevented by preventing the swinging of the inertial body, but the end lock of the lock member is described. Not. Further, in the retractor for seat belt described in Patent Document 2, it is described that an end locking due to a malfunction of the lock member itself is provided while an automatic lock mechanism is provided. In addition, there is no description of an end lock due to a malfunction of the webbing acceleration sensing means.

  The present invention has been made in view of the above-described circumstances, and an object thereof is a compact seat belt capable of preventing the occurrence of end lock due to malfunction of the webbing acceleration sensing means of the emergency lock mechanism and the lock member itself. It is to provide a retractor for use.

In order to achieve the above-described object, a seatbelt retractor according to the present invention is characterized by the following (1) to (6).
(1) a spindle that is rotatably supported by a frame and on which a webbing is wound;
A locking member that locks rotation of the spindle in the webbing pull-out direction by engaging with the frame;
A steering wheel that is rotatably supported by the spindle and that operates the lock member by causing a rotation delay with respect to the spindle;
First locking means pivotally supported on the steering wheel is provided, and when the webbing is pulled out at a predetermined speed or more, the first locking means is displaced to the first operating position. Webbing acceleration sensing means for preventing rotation of the steering wheel in the webbing pull-out direction;
A control plate that rotates at a different speed from the spindle according to the rotation of the spindle;
With
The first locking means is controlled by the control plate so as to be held at a first non-operating position where rotation of the steering wheel in the webbing pull-out direction is not blocked when the winding of the webbing is completed, and,
The first locking means is held in the first non-operating position when the webbing winding is completed, thereby preventing a delay in the rotation of the steering wheel with respect to the spindle, and the locking member and the frame. A retractor for a seat belt, wherein the seat belt retractor is held at an unlocked position where it is not engaged.
(2) The webbing acceleration sensing means is supported at one end by the steering wheel and at the other end by the first locking means, and the first locking means is at the first inoperative position. Further comprising a biasing means for WS biasing toward the
The first locking means includes a claw portion that is engageable with an inner tooth formed on an inner peripheral surface of a cover member attached to the frame, and a WS for extending in an axial direction toward the control plate. A protrusion, and a protrusion for preventing the lock member from protruding in the axial direction toward the spindle,
The control plate has a WS cam for controlling the first locking means to be held in the first inoperative position by contacting the WS protrusion when the webbing is completely wound. And
Between the spindle and the steering wheel, the steering wheel is biased against the spindle so that the lock member is held in the unlocked position and the spindle and the steering wheel rotate together. Means are provided,
A cam groove is formed on the side surface of the spindle to accommodate the protrusion for preventing the lock member from popping out,
The cam groove prevents the lock member from jumping out of the unlocked position when the first locking means is held in the first inoperative position when the winding of the webbing is completed. The retractor for a seat belt according to (1), further comprising a pop-out prevention portion that engages with the protrusion portion for pop-out prevention.
(3) having a second locking means pivotally supported by the steering wheel so that the webbing is pulled out from the first predetermined amount until being wound up by the second predetermined amount; An automatic locking mechanism that displaces the second locking means to the second operating position and prevents rotation of the steering wheel in the webbing pull-out direction;
The second locking means is held by the control plate at the second operating position from when the webbing is pulled out by the first predetermined amount until it is wound up by the second predetermined amount. The seatbelt retractor according to (1) or (2), wherein the seatbelt retractor is controlled.
(4) The automatic locking mechanism further includes an ALR biasing means having one end supported by the steering wheel and the other end supported by the second locking means,
The first locking means includes a claw portion that is engageable with an inner tooth formed on an inner peripheral surface of a cover member attached to the frame, and a WS for extending in an axial direction toward the control plate. A protrusion, and
The second locking means has an ALR projection extending in the axial direction toward the control plate, and an abutting arm part capable of contacting the first locking means,
A WS cam for controlling the first locking means to be held in the first inoperative position by contacting the WS protrusion when the webbing is completely wound; When the webbing is pulled out by the first predetermined amount, the second locking means snaps to the second operating position beyond the dead point of the ALR biasing means by contacting the ALR protrusion. An ALR cam to be operated,
When the second locking means snaps to the second operating position, the abutting arm portion comes into contact with the first locking means, and the claw portion of the first locking means is moved. Engage with the inner teeth of the cover member to prevent rotation of the steering wheel in the webbing pull-out direction,
The WS cam contacts the WS protrusion when the webbing is pulled out for the second predetermined amount after the first predetermined amount is pulled out, and the first locking means is the first locking means. The second locking means is controlled to be held in the non-actuated position. At this time, the second locking means is brought into contact with and pressed against the abutting arm portion. The retractor for a seat belt according to (3), wherein the arm portion snaps beyond the dead point of the ALR biasing means to a second non-operating position where the arm portion is separated from the first locking means. .
(5) The lock member is provided with a pin portion that penetrates a cam hole formed in the steering wheel,
A cancel lever having a long hole into which the pin portion penetrating the cam hole is inserted and a projection for a lock member extending in the axial direction toward the control plate is swingable on the steering wheel. Supported by
(4) The ALR cam of the control plate constitutes a lock member cam that controls the lock member so that it cannot be engaged with the frame when the winding of the webbing is completed. Seat belt retractor.
(6) The automatic lock mechanism further includes an ALR biasing unit having one end supported by the steering wheel and the other end supported by the second locking unit,
The first locking means includes a claw portion that is engageable with an inner tooth formed on an inner peripheral surface of a cover member attached to the frame, and a WS for extending in an axial direction toward the control plate. A protrusion, and
The second locking means has an ALR projection extending in the axial direction toward the control plate, and an abutting arm part capable of contacting the first locking means,
A WS cam for controlling the first locking means to be held in the first inoperative position by contacting the WS protrusion when the webbing is completely wound; When the webbing is pulled out by the first predetermined amount, the second locking means snaps to the second operating position beyond the dead point of the ALR biasing means by contacting the ALR protrusion. When the webbing is wound up by a second predetermined amount, the second locking means is brought into contact with the ALR protrusion when the webbing is wound up by the second predetermined amount, and the dead end of the ALR biasing means is exceeded. An ALR cam that causes the arm portion to snap to a second non-actuated position away from the first locking means;
When the webbing is pulled out by the first predetermined amount and the second locking means snaps to the second operating position, the abutting arm portion contacts the first locking means, Engaging the claw portion of the first locking means with the internal teeth of the cover member to prevent rotation of the steering wheel in the webbing pull-out direction;
When the webbing is wound up by the second predetermined amount, the ALR cam is brought into contact with the ALR projection to cause the second locking means to snap to the second inoperative position. The WS cam is controlled so that the first locking means is held in the first non-operating position by contacting the WS protrusion and the WS cam. The retractor for a seat belt according to (3), wherein rotation in the pull-out direction is not prevented.
(7) A gear having a drive gear that rotates integrally with the spindle, a driven gear that has fewer teeth than the drive gear that rotates integrally with the control plate, and an idle gear that meshes with both the drive and the driven gear. Further equipped with a speed increasing mechanism,
The seat belt retractor according to any one of (1) to (6), wherein the control plate rotates at a speed higher than the rotation of the spindle by the gear speed increasing mechanism.

  According to the seatbelt retractor of the present invention, when the winding of the webbing is completed, the control plate prevents the first locking means of the webbing acceleration sensing means from being prevented from rotating in the webbing pull-out direction of the steering wheel. Control is performed so as to be held in the operating position, and at the same time, a delay in rotation of the steering wheel relative to the spindle is prevented by the first locking means, and the lock member is held in the unlocked position where it does not engage with the frame. Thereby, it is possible to prevent occurrence of end lock due to malfunction of the webbing acceleration sensing means of the emergency lock mechanism and the lock member itself with a compact configuration.

It is a disassembled perspective view of the seatbelt retractor of 1st Embodiment of this invention. It is a front view of a steering wheel. (A) is a perspective view of a bearing cover, (b) is a front view of a bearing cover. (A) is the cam side perspective view of a control plate, (b) is the front view. It is a figure of the total amount storage state which permeate | transmits and shows each component controlled by each cam of a control plate. It is a figure of the webbing mounting | wearing state which permeate | transmits and shows each component controlled by each cam of a control plate. In order to explain the canceller function of the seatbelt retractor, it is a view through which each component controlled by each cam of the control plate is shown, (a) shows a state in which the WS lever is operated, (b) Shows a state in which the WS lever is locked to the inner teeth of the bearing cover, and (c) shows a state in which the lock dock is engaged. It is a figure for demonstrating switching of an automatic locking mechanism, (a) shows the state just before pulling out all the webbing, (b) shows the state which an automatic locking mechanism act | operates by pulling out all, (c) Is a state where the webbing is wound up by a predetermined amount and the automatic locking mechanism is activated, (d) is a state where the webbing is wound while the automatic locking mechanism is activated, and (e) is a state where the webbing is further FIG. 4 shows a state in which the operation release operation of the automatic lock mechanism is started after being wound, and FIG. 5F shows a state in which the operation of the automatic lock mechanism is released. It is a figure for demonstrating operation | movement of WS lever of a webbing acceleration sensing means, (a) is an initial state without the phase shift between the inertial body 70 and the steering wheel 40, (b) produces this phase shift, A state in which the WS lever is close to the inner teeth of the bearing cover, (c) shows a state in which the phase shift further occurs and the WS lever is engaged. It is a figure for demonstrating the action | operation of a lock dock, (a) is a state at the time of WS lever engagement, (b) is a tooth dock engagement start state of a lock dock, (c) is complete of a lock dock. Indicates the binding state. It is a figure of the total storage state which permeate | transmits and shows each component controlled by each cam of the control plate concerning the seatbelt retractor of 2nd Embodiment. It is a figure of the webbing mounting state which permeate | transmits and shows each component controlled by each cam of the control plate concerning the seatbelt retractor of FIG. It is a figure for demonstrating the canceller function of the retractor for seatbelts of FIG. 11, (a) shows the state which WS lever act | operated, (b) is the state which WS lever locked to the internal tooth of the bearing cover (C) shows a state where the lock dock is engaged. It is a figure for demonstrating switching of an automatic locking mechanism, (a) shows the state just before pulling out all the webbing, (b) shows the state which an automatic locking mechanism act | operates by pulling out all, (c) Is a state where the webbing is wound up by a predetermined amount and the automatic locking mechanism is activated, (d) is a state where the webbing is wound while the automatic locking mechanism is activated, and (e) is a state where the webbing is further FIG. 4 shows a state in which the operation release operation of the automatic lock mechanism is started after being wound, and FIG. 5F shows a state in which the operation of the automatic lock mechanism is released.

  Hereinafter, preferred embodiments of the seatbelt retractor of the present invention will be described in detail with reference to the drawings.

(First embodiment)
The seatbelt retractor of this embodiment has both an emergency locking mechanism having a webbing acceleration sensing means and a vehicle body acceleration sensing means, and an automatic locking mechanism. As shown in FIG. 1, the seatbelt retractor includes a metal (for example, aluminum alloy) spindle 1 around which a webbing (not shown) is wound, and a spring that urges the spindle 1 to rotate in the winding direction. Type winding device 2, a metal U-shaped frame 10 that rotatably supports the spindle 1, a metal (for example, iron) lock dock 20 as a lock member, and a resin steering wheel 40 A metal (for example, zinc alloy) inertial body (inert mass) 70 for imparting mass to the steering wheel 40, a resin ratchet wheel 30 as a latch member attached to the inertia mass 70, and webbing acceleration sensing Resin WS lever 50 as the first locking means of the means, and resin AL as the second locking means of the automatic locking mechanism A lever 60, a resin cancel lever 90 which is a cancel member attached to the lock dock 20, a resin control plate 80, a vehicle body acceleration sensing means 110 for sensing the acceleration of the vehicle body, the lock dock 20, and the ratchet wheel 30 And a resin bearing cover 100 as a cover member that covers main components of the emergency lock mechanism such as the steering wheel 40, the WS lever 50, the inertial body 70, and the vehicle body acceleration sensing means 110. The inertia mass 70 may be made of resin.

  As shown in FIG. 1, the frame 10 has left and right side plates 10A and 10B that face each other with a central portion in the axial direction of the spindle 1, and an emergency lock mechanism and an automatic lock mechanism are disposed outside one side plate 10A. The winding device 2 is disposed outside the other side plate 10B. The shaft 5 on one end side of the spindle 1 passes through the center holes 45, 75, 85 of the steering wheel 40, inertia mass 70, and control plate 80, and the drive gear 6 is fitted to the tip of the shaft 5 so as to rotate integrally. ing.

  An idle gear 7 is pivotally supported on the bearing cover 100 attached to one side plate 10 </ b> A of the frame 10, and meshes with both the drive gear 6 and a driven gear 81 formed on one side of the control plate 80. ing. Accordingly, the rotation of the spindle 1 is transmitted from the drive gear 6 to the driven gear 81 via the idle gear 7, and the control plate 80 having the driven gear 81 rotates at an increased speed in conjunction with the spindle 1. . The speed increasing ratio of the gear speed increasing mechanism comprising the drive gear 6, the idle gear 7, and the driven gear 81 is such that the rotation of the spindle 1 when the webbing is fully pulled out to the fully wound state is controlled by the control plate 80. It is set to a numerical value that can be converted into one rotation. In the present embodiment, the number of teeth of the drive gear 6 is 22, the number of teeth of the idle gear 7 is 13, and the number of teeth of the driven gear 81 is 21. The drive, idle, and driven gears 6, 7, and 81 are made of resin.

  A large number of internal teeth 11 into which the claws 22 of the lock dock 20 are fitted are formed on the inner periphery of the circular opening of the side plate 10 </ b> A of the frame 10. The lock dock 20 is slidably accommodated in a space secured between one end face of the spindle 1 and a metal (for example, iron) cover plate 29 fixed to the end face. In addition, a spring accommodation hole 3 that supports and accommodates one end of the coil spring 28 is formed on one end face of the spindle 1. Then, by supporting the other end of the coil spring 28 on a spring support portion (not shown) formed on the back surface of the steering wheel 40, the coil spring 28 rotates the steering wheel 40 counterclockwise with respect to the spindle 1 (unlocked position). ) To allow the spindle 1 and the steering wheel 40 to rotate integrally. The lock dock 20 is held at the unlocked position where the claw 22 is separated from the internal teeth 11 by inserting the cam pin 21 into the cam hole 41 formed in the steering wheel 40. Further, when necessary, the steering wheel 40 is rotated relative to the spindle 1 in the clockwise direction (actually, the spindle 1 is rotated), and the movement of the cam pin 21 resists the force of the coil spring 28. Then, the nail 22 jumps out. Then, the claw 22 jumping out is engaged with the inner teeth 11 of the frame 10 to lock the spindle 1 to the inner teeth 11 of the frame 10 (that is, move to the lock position) and rotate in the webbing pull-out direction. Is mechanically locked.

  The steering wheel 40 is supported by the spindle 1 so as to be relatively rotatable. As shown in FIG. 2, the steering wheel 40 is fitted into the cam hole 41 with which the cam pin 21 of the lock dock 20 is engaged and the shaft hole 51 of the WS lever 50. On the spindle side of the ALR lever 60, a convex shaft 42 that supports the lever 50 so that it can swing, a convex shaft 43 that supports the ALR lever 60 so that it can move freely and swingably. Another cam hole 44 that accommodates the protruding convex portion 64, a convex shaft 47 that swingably supports the cancel lever 90 by being fitted in the shaft hole 92 of the cancel lever 90, and prevents the WS lever 50 from popping out of the lock member. And a notch 48 that allows the projection 54 to swing.

  The cam hole 41 pushes the claw 22 of the lock dock 20 outward through the cam pin 21 when the steering wheel 40 rotates relative to the spindle 1. For example, when the steering wheel 40 is delayed in rotation with respect to the spindle 1 when the webbing is pulled out, the lock dock 20 is operated to the lock side by the relative rotation of the spindle 1 and the steering wheel 40.

  The tip of the cam pin 21 that has penetrated the cam hole 41 is inserted into a long hole 93 of a cancel lever 90 that is swingably supported by the convex shaft 47 of the steering wheel 40. The cancel lever 90 has a locking member protrusion 91 that extends in the axial direction toward the control plate 80 at an arm portion different from the arm portion in which the elongated hole 93 is formed around the shaft hole 92.

  The WS lever 50 includes a claw 52 that can be engaged with an inner tooth 108 (FIG. 3) of the bearing cover 100 described later, a WS protrusion 53 that extends in the axial direction toward the control plate 80, and the spindle 1. And a protrusion 54 for preventing the lock member from protruding in the axial direction. The claws 52, the WS protrusions 53, and the lock member protrusion prevention protrusions 54 are provided on the respective arm portions extending from the shaft hole 51 in a direction perpendicular to the axial direction of the shaft hole 51. The WS lever 50 is rotationally biased in a direction in which the claw 52 is retracted inward by a WS spring 58 that is a biasing means for WS, and is held in a first inoperative position that does not engage with the internal teeth 108 in a normal state. The The WS spring 58 is supported at one end by the steering wheel 40 and at the other end by the WS lever 50.

  The ALR lever 60 includes a cam pin 62 that is an ALR protrusion extending in the axial direction toward the control plate 80, the protrusion 64 described above, and a claw arm portion 55 provided with the claw 52 of the WS lever 50. And an abutting arm portion 65 capable of abutting on the arm. The cam pin 62 and the convex portion 64 extend in the axial direction from the same arm portion, and the arm portion and the abutting arm portion 65 extend from the long hole 61 in a direction perpendicular to the axial direction of the long hole 61. Each extends. The ALR lever 60 supports the other end portion of an ALR spring 69 which is an ALR biasing means whose one end portion is supported by the steering wheel 40. The ALR lever 60 is a second member in which the abutting arm portion 65 abuts against the claw arm portion 55 of the WS lever 50 while the convex portion 64 is guided in the other cam hole 44 of the steering wheel 40 by the ALR spring 69. Between the operating position and the second non-operating position where the claw arm portion 55 does not abut, the snap action is performed beyond the dead point of the ALR spring 69.

  The inertia body 70 is attached to the steering wheel 40 with the WS lever 50, the ALR lever 60, and the like assembled to the steering wheel 40, and the center hole 75 is fitted to the shaft 5 of the spindle 1 so as to be relatively rotatable. Yes. Further, the inertia body 70 is assembled so as to be slightly rotatable relative to the steering wheel 40 by a plurality of claw members 46 provided around the center hole 45 of the steering wheel 40. Protrusions 71 a and 7 ab (see FIG. 5) are provided on the side surfaces of the inertial body 70, and the projecting parts 71 a and 71 b sandwich the bases in the vicinity of the bases of the WS protrusions 53 of the WS lever 50. Is located. When relative rotation occurs between the inertial body 70 and the steering wheel 40, the convex portion 71a of the inertial body 70 presses the WS lever 50 supported by the steering wheel 40, and the claw of the WS lever 50 52 is displaced to the first operating position protruding outward and meshed with the internal teeth 108 of the bearing cover 100. As a result, the webbing acceleration sensing means prevents the steering wheel 40 from rotating in the webbing pull-out direction. In addition, the inertia member 70 controls a notch 72 through which the protrusion 53 of the WS lever 50 penetrates toward the control plate 80 side, a cam pin 62 of the ALR lever 60, and a lock member protrusion 91 of the cancel lever 90. Through-holes 73 and 74 are formed so as to pass through the plate 80 in a swingable manner.

  As shown in FIG. 3, a cylindrical wall 107 protrudes from the inner surface side of the face plate 101 of the bearing cover 100, and an inner tooth 108 that can engage with the WS lever 50 is provided on the inner periphery of the cylindrical wall 107. ing. Further, the bearing cover 100 is provided with a base portion 110A constituting the vehicle body acceleration sensing means 110, and a ball cover 127 for holding a ball (not shown) is attached thereto. Then, when a ball (not shown) moves in accordance with the vehicle body acceleration, the VS sensor lever 120 as the operating member swings and the claw 121 is lifted, and engages with the external teeth 31 provided on the outer periphery of the ratchet wheel 30. Then, the ratchet wheel 30 is locked.

  The control plate 80 is provided with a center hole 85 that is rotatably fitted to the bearing cover 100 at the center, and the above-described driven gear 81 is provided on one side. Also, on the side surface opposite to the side where the driven gear 81 is provided, as shown in FIG. 4, a first cam 86 and a second cam 87 project in the axial direction and are formed in a rib shape. The first cam 86 of the present embodiment is a WS cam that prevents end lock due to malfunction of the WS lever 50 of the webbing acceleration sensing means, and via the WS lever 50 when the automatic lock mechanism is released. Thus, it functions as an ALR cam that snaps the ALR lever 60. Further, the second cam 87 is an ALR cam that snaps the ALR lever 60 when the automatic lock mechanism is operated, and also functions as a lock member cam that prevents an end lock due to a malfunction of the lock dock 20 itself. To do.

  The first cam 86 is formed in a circular arc shape concentric with the outer peripheral surface of the control plate 80, and when the webbing winding is completed, the first cam 86 contacts the projection 53 of the WS lever 50 in the first non-operating position. A position of contact with the protrusion 53 of the WS lever 50 in the first operating position on the outer peripheral surface when the webbing that has been pulled out in the first predetermined amount is wound up by the second predetermined amount; , So as to include.

  The second cam 87 has a first arc portion 87a concentric with the outer peripheral surface of the control plate 80, and a step on one end side of the first arc portion 87a, and is closer to the inner circumference side than the first arc portion 87a. A second arc portion 87b that is formed and concentric with the outer peripheral surface of the control plate 80, and is formed on the other end side of the first arc portion 87a, and has a side surface 87d that forms a guide passage 87c and extends in the radial direction. A portion. The side surface 87d of the second cam 87 is formed at a position where the webbing is brought into contact with the cam pin 62 of the ALR lever 60 when the webbing is pulled out from immediately before the full amount is pulled out to the full amount that is the first predetermined amount. Further, the first arc portion 87a of the second cam 87 is formed so that the lock member projection 91 of the cancel lever 90 attached to the lock dock 20 at the unlocking position is in contact with the outer peripheral surface when the winding of the webbing is completed. It is formed so as to include a contact position. Further, the guide passage 87c holds the cam pin 62 during assembly and restricts the ALR lever 60.

  Further, the protrusion 54 for preventing the lock member from popping out of the WS lever 50 is accommodated in the cam groove 8 formed on one end surface of the spindle 1. As shown in FIG. 5, the cam groove 8 has a circumferential direction and a radial direction so as to allow the protrusion 54 to move when the steering wheel 40 and the spindle 1 rotate relative to each other and when the WS lever 50 swings. It is formed in the substantially L shape extended to. The cam groove 8 has a protrusion for preventing the lock member 20 from popping out from the unlock position when the WS lever 50 is held in the first non-operating position when the webbing winding is completed. A wall surface 8a is formed as a pop-out preventing portion that contacts and engages with the portion 54 in the circumferential direction.

Next, the operation of the seat belt retractor of the present embodiment will be described.
As shown in FIG. 5, when the entire amount of webbing is stored, the protrusion 53 of the WS lever 50 is in contact with the outer peripheral surface of the first cam 86, and the WS lever 50 rotates in the webbing pull-out direction of the steering wheel 40. Is held in a non-rotatable position in the first non-operating position in which the claw 52 that does not engage with the internal teeth 108 of the bearing cover 100 is retracted.

  At this time, the locking member pop-out preventing projection 54 of the WS lever 50 is positioned in contact with the wall surface 8 a of the cam groove 8 of the spindle 1, so that a delay in rotation of the steering wheel 40 with respect to the spindle 1 is prevented. For this reason, the lock dock 20 is held at the unlocked position where it cannot be engaged with the internal teeth 11 of the frame 10.

  Similarly, the protrusion 91 of the cancel lever 90 is in contact with the outer peripheral surface of the second cam 87, and the lock dock 20 cannot be engaged with the internal teeth 11 of the frame 10 by the cancel lever 90. It is held non-rotatable at the unlocked position. The second arc portion 87b of the second cam 87 opposes the ALR lever 60 in the vicinity thereof, and the ALR lever 60 that is biased by the ALR spring 69 and is in the second inoperative position is snapped by the snap operation. 2 is prevented from moving to the operating position.

  When the webbing is pulled out from the full storage state shown in FIG. 5, the control plate 80 rotates relative to the spindle 1 in the direction of arrow A. Therefore, the control plate 80 rotates relative to the lock dock 20 supported by the spindle 1 and the WS lever 50 and ALR lever 60 supported by the steering wheel 40 rotating together with the spindle 1 in the direction of arrow A.

  Thereby, the contact between the protrusion 53 of the WS lever 50 and the first cam 86 is released, and the contact between the protrusion 91 of the cancel lever 90 and the second cam 87 is released. Further, the engagement with the wall surface 8a of the protrusion 54 for preventing the lock member popping out of the WS lever 50 is released. For this reason, the WS lever 50 held in the first non-operating position by the WS spring 58 can swing and rotate to the first operating position that prevents the steering wheel 40 from rotating in the webbing pull-out direction. Further, the lock dock 20 held at a position where it cannot be engaged with the internal teeth 11 of the frame 10 by the coil spring 28, as shown in FIGS. 7A to 7C, After swinging to the operating position, it is possible to jump out to the lock position that engages with the inner teeth 11.

  Therefore, as shown in FIG. 6, in the webbing wearing state in which the buckle is attached to the tongue, the webbing can be pulled out and taken up freely at normal times when the deceleration of a predetermined value or more does not act on the vehicle. Further, in a webbing wearing state, the webbing acceleration sensing means and the vehicle body acceleration sensing means can be operated in an emergency in which a deceleration greater than a predetermined value acts on the vehicle.

  Further, as shown in FIG. 8 (a), in the vicinity of the full pulling out of the webbing further, the cam pin 62 of the ALR lever 60 abuts on the side surface 87d of the ALR cam 87 and further pulls out along the side surface 87d. Move radially inward. For this reason, the ALR lever 60 snaps to the second operating position beyond the dead point of the ALR spring 69. As a result, as shown in FIG. 8B, the abutting arm portion 65 of the ALR lever 60 abuts on the claw arm portion 55 of the WS lever 50 to swing the WS lever 50, and the claw of the WS lever 50. 52 is engaged with the internal teeth 108 of the bearing cover 100. Accordingly, as shown in FIG. 8C, the automatic locking mechanism is activated, and the rotation of the spindle 1 in the pulling direction is restricted.

  In this state, as shown in FIG. 8D, the spindle 1 can rotate while flipping the WS lever 50 inward by the internal teeth 108 together with the steering wheel 40, so that the webbing can be taken up. In particular, the abutment arm portion 65 of the ALR lever 60 is in contact with the claw arm portion 55 of the WS lever 50. The ALR lever 60 is supported by the steering wheel 40 so as to be movable by the elongated hole 61. Therefore, when the WS lever 50 is bounced, the WS lever 50 can be moved together with the swing of the WS lever 50 and does not hinder the WS lever 50 from being bounced. For this reason, when the child seat or the like is attached, the child seat can be securely fixed to the vehicle seat by setting the automatic locking mechanism in an activated state and winding the surplus webbing with the winding device 2.

  Then, as shown in FIG. 8 (e), when the webbing is wound up by the second predetermined amount from the vicinity of the entire amount, the protrusion 53 of the WS lever 50 comes into contact with the end of the first cam 86 and the radial direction. Guided outside. When the webbing is further wound, as shown in FIG. 8F, the protrusion 53 of the WS lever 50 comes into contact with the outer peripheral surface of the WS cam 86, and the WS lever 50 is moved to the first inoperative position. Hold on. For this reason, when the WS lever 50 contacts and is pressed against the contact arm portion 65 of the ALR lever 60, the ALR lever 60 moves to the second inoperative position where the contact arm portion 65 is separated from the WS lever 50. The snap operation is performed beyond the dead point of the ALR spring 69. Thereby, the operation state of the automatic lock mechanism is switched to the state in which the emergency lock mechanism can be operated.

  Further, after the occupant releases the fastening between the tongue and the buckle from the webbing wearing state, the webbing is wound by the spring force of the winding device 2. Then, the protrusion 53 of the WS lever 50 contacts the first cam 86 from before the winding is completed to when the winding is completed, and the WS lever 50 is held at the first inoperative position. Further, the locking member pop-out preventing projection 54 of the WS lever 50 is engaged with the wall surface 8a of the cam groove 8 of the spindle 1, and the projection 91 of the cancel lever 90 is brought into contact with the second cam 87 to lock the lock. The dock 20 is held in the unlocked position. As a result, it is possible to prevent end lock due to malfunction of the webbing acceleration sensing means and to prevent end lock of the lock dock 20 itself.

  Further, when the webbing is pulled out at a predetermined speed or more due to a vehicle collision or the like in the webbing wearing state shown in FIG. 6 and a sudden webbing pulling force acts on the spindle 1, the inertial body shown in FIG. Relative rotation occurs between the inertial body 70 and the steering wheel 40 from an initial state where there is no phase shift between the steering wheel 40 and the steering wheel 40. For this reason, as shown in FIG. 9B, the convex portion 71 a of the inertia body 70 that is in contact with the WS lever 50 presses the WS lever 50 and rotates the WS lever 50 in the clockwise direction. When the predetermined angle is reached, the claw 52 of the WS lever 50 engages with the internal teeth 108 of the bearing cover 100 (see FIG. 9C). When the engagement is released, the other convex portion 71b of the inertia body 70 that is in contact with the WS lever 50 presses the WS lever 50 and rotates the WS lever 50 counterclockwise.

  Then, as shown in FIG. 10A, when the webbing is further pulled out while the steering wheel 40 is fixed by engaging the claw 52 of the WS lever 50 with the internal teeth 108 of the bearing cover 100, the steering wheel 10 causes a rotation delay with respect to the spindle 1, and the lock dock 20 in which the cam pin 21 is accommodated in the cam hole 41 of the steering wheel 40 moves outward as shown in FIG. 22 jumps out and engages with the internal teeth 11 of the frame 10. FIG. 10C shows a state where the webbing is further pulled out and the claw 22 of the lock dock 20 is completely fastened to the inner teeth 11 of the frame 10. As a result, the spindle 1 is locked and rotation of the webbing in the pulling direction is prevented.

  Further, when the vehicle body acceleration sensing means 110 is activated, the ratchet wheel 30 is locked by the claws 121 of the VS sensor lever 120 engaging the external teeth 31 of the ratchet wheel 30. When the ratchet wheel 30 is locked, relative rotation occurs between the inertial body 70 to which the ratchet wheel 30 is fixed and the steering wheel 40, so that the spindle is acted by the action of the WS lever 50 and the lock dock 20 in the same manner as described above. 1 is locked.

  As described above, according to the seat belt retractor of the present embodiment, when the webbing winding is completed, the control plate 80 prevents the WS lever 50 of the webbing acceleration sensing means from rotating in the webbing pull-out direction of the steering wheel 40. At the same time, the WS lever 50 prevents the rotation of the steering wheel 40 with respect to the spindle 1 and prevents the lock dock 20 from engaging with the frame 10. Hold. Thereby, it is possible to prevent occurrence of the end lock 20 due to malfunction of the webbing acceleration sensing means of the emergency lock mechanism and the lock dock itself with a compact configuration.

  Specifically, the function of preventing the end lock due to the malfunction of the webbing acceleration sensing means can be performed by the claw 52 and the WS protrusion 53 of the WS lever 50 and the first cam 86 of the control plate 80. Further, the function of preventing the end lock due to malfunction of the lock dock 20 itself is that the lock member pop-out preventing projection 54 of the WS lever 50, the coil spring 28 provided between the spindle 1 and the steering wheel 40, The WS is formed by the cam groove 8 formed on the side surface of the spindle 1 so as to movably accommodate the lock member protrusion preventing protrusion 54 and having a wall surface 8a that can be brought into contact with the protrusion 54 and engaged therewith. This can be performed together with the end lock of the lever 50.

Further, the operation and release operation of the automatic locking mechanism can be controlled by the control plate 80, and a compact configuration can be maintained.
Specifically, the automatic locking mechanism includes an ALR lever 60 having an ALR projection 62 and an abutment arm 65, and an ALR spring 69, and the WS lever 50 includes a claw 52 and a WS projection 53. The control plate 80 includes a first cam 86 and a second cam 87. The ALR spring 69 snaps to the second operating position by the second cam 87 when the webbing is pulled out by the first predetermined amount, whereby the abutment arm portion 65 is moved to the WS lever 50. The claw 52 of the WS lever 50 is brought into contact with the inner teeth 108 of the bearing cover 100 to prevent the steering wheel 40 from rotating in the webbing pull-out direction. Further, the first cam 86 contacts the WS protrusion 53 when the webbing is pulled out for the second predetermined amount after the first predetermined amount is pulled out, and the WS lever 50 is moved to the first inoperative position. When the WS lever 50 is held and pressed against the abutting arm portion 65, the ALR lever 60 is moved to the second inoperative position where the abutting arm portion 65 is separated from the WS lever 50. Snaps over 69 dead points.

  In this embodiment, the function of preventing the end lock due to the malfunction of the lock dock 20 itself is that the cam pin 21 of the lock dock 20, the long hole 93 and the lock lever protrusion 91, the lock lever 90, and the lock member This is also performed by the second cam 87 also serving as a cam.

  The control plate 80 is rotated at a speed higher than the rotation of the spindle 1 by the gear speed increasing mechanism having the drive gear 6, the driven gear 81, and the idle gear 7, so that the webbing is wound up and pulled out. The swing control of the WS lever 50, the ALR lever 60, and the cancel lever 90 can be easily performed. Specifically, the speed of the control plate 80 is increased so that the control plate 80 rotates by one tooth (for one rotation + one tooth rotation) with respect to one rotation of the spindle 1. A schedule for swinging the lever 50, the ALR lever 60, and the cancel lever 90 can be created.

(Second Embodiment)
Next, a seatbelt retractor according to a second embodiment of the present invention will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected about the same or equivalent part as 1st Embodiment, and description is abbreviate | omitted or simplified.

  The seat belt retractor of the present embodiment differs from that of the first embodiment mainly in that it does not have a cancel lever and in the cam shape of the control plate. That is, in the seat belt retractor of the present embodiment, the function of preventing end lock due to malfunction of the lock dock 20 itself is performed only by the WS lever 50 of the webbing acceleration sensing means. In the first embodiment, the operation releasing operation of the automatic locking mechanism is performed only by the first cam 86 of the control plate 80. However, in this embodiment, the operation releasing operation is performed by the first cam 86 of the control plate 80. And the second cam 87. Accordingly, the second cam 87 functions as an ALR cam that performs the operation and the operation release operation of the automatic locking mechanism.

  Specifically, as shown in FIG. 11, the control plate 80 includes a first cam 86 and a second cam 187 similar to those in the first embodiment. In the second cam 187, a first arc portion 187a concentric with the outer peripheral surface of the control plate 80 is formed over a substantially half circumference, and extends toward the inner circumference on one end side of the first arc portion 187a. A guide portion having a side surface 187b is formed, and a portion having a side surface 87d that forms a guide passage 87c and extends in the radial direction is formed on the other end side of the first arc portion 187a as in the first embodiment. .

  As in the first embodiment, the side surface 87d of the second cam 187 is located at a position where the webbing is brought into contact with the cam pin 62 of the ALR lever 60 when the webbing is pulled out from just before the full amount is pulled out to the first predetermined amount. It is formed. Further, the side surface 187b of the second cam 87 is formed at a position where the webbing is brought into contact with the cam pin 62 of the ALR lever 60 when the webbing is wound up by the second predetermined amount from the full amount being the first predetermined amount.

  Therefore, in the seatbelt retractor of the present embodiment, the protrusion 53 of the WS lever 50 is in contact with the outer peripheral surface of the first cam 86 in the state in which all the webbing is stored as shown in FIG. The first non-operating position where the rotation of the steering wheel 40 in the webbing pull-out direction is not blocked, that is, the position where the claw 52 that does not engage with the internal teeth 108 of the bearing cover 100 is retracted is held unrotatable.

  At this time, the locking member pop-out preventing projection 54 of the WS lever 50 is in contact with and engaged with the wall surface 8 a of the cam groove 8 of the spindle 1, thereby preventing the rotation delay of the steering wheel 40 with respect to the spindle 1. For this reason, the lock dock 20 is held at the unlocked position where it cannot be engaged with the internal teeth 11 of the frame 10.

  When the webbing is pulled out from the total amount storage state shown in FIG. 11, the control plate 80 rotates relative to the spindle 1 in the direction of arrow A. Therefore, the control plate 80 rotates relative to the lock dock 20 supported by the spindle 1 and the WS lever 50 and ALR lever 60 supported by the steering wheel 40 rotating together with the spindle 1 in the direction of arrow A.

  As a result, the contact between the protrusion 53 of the WS lever 50 and the first cam 86 is released, and the engagement with the wall surface 8a of the lock member protrusion prevention protrusion 54 of the WS lever 50 is released. For this reason, the WS lever 50 held in the first non-operating position by the WS spring 58 can swing and rotate to the first operating position that prevents the steering wheel 40 from rotating in the webbing pull-out direction. Further, the lock dock 20 held in the unlocked position by the coil spring 28 has the internal teeth 11 after the WS lever 50 is swung to the first operating position, as shown in FIGS. It is possible to jump out to the locked position where it engages.

  Accordingly, as shown in FIG. 12, in the webbing wearing state in which the buckle is attached to the tongue, the webbing can be freely pulled out and taken up at normal times when a deceleration of a predetermined value or more does not act on the vehicle. Further, in a webbing wearing state, the webbing acceleration sensing means and the vehicle body acceleration sensing means can be operated in an emergency in which a deceleration greater than a predetermined value acts on the vehicle.

  Then, as shown in FIG. 14 (a), in the vicinity of the full amount drawer where the webbing is further pulled out, the cam pin 62 of the ALR lever 60 abuts on the side surface 87d of the second cam 187, and is further pulled out to the side surface 87d. And move radially inward. For this reason, the ALR lever 60 snaps to the second operating position beyond the dead point of the ALR spring 69. As a result, as shown in FIG. 14B, the contact arm portion 65 of the ALR lever 60 contacts the claw arm portion 55 of the WS lever 50 to swing the WS lever 50, and the claw of the WS lever 50. 52 engages with the internal teeth 108 of the bearing plate 100. Accordingly, as shown in FIG. 14C, the automatic locking mechanism is activated, and the rotation of the spindle 1 in the pulling direction is restricted.

  In this state, as shown in FIG. 14 (d), the spindle 1 can rotate while flipping the WS lever 50 inward by the internal teeth 108 together with the steering wheel 40, so that the webbing can be taken up. In particular, the abutment arm portion 65 of the ALR lever 60 is in contact with the claw arm portion 55 of the WS lever 50. The ALR lever 60 is supported by the steering wheel 40 so as to be movable by the elongated hole 61. Therefore, when the WS lever 50 is bounced, the WS lever 50 can be moved together with the swing of the WS lever 50 and does not hinder the WS lever 50 from being bounced. For this reason, when the child seat or the like is attached, the child seat can be securely fixed to the vehicle seat by setting the automatic locking mechanism in an activated state and winding the surplus webbing with the winding device 2.

  Then, as shown in FIG. 14 (e), when the webbing is wound up by the second predetermined amount from the vicinity of the full amount drawing, the cam pin 62 of the ALR lever 60 contacts the side surface 187b of the second cam 87, and the ALR lever 60 Rotates clockwise while moving the long hole 61 with respect to the convex shaft 43. When the webbing is further wound, the ALR lever 60 is snapped to the second non-operating position beyond the dead point of the ALR spring 69 as shown in FIG. As a result, the contact arm portion 65 of the ALR lever 60 is separated from the claw arm portion 55 of the WS lever 50.

  At the same time, when the webbing is wound up from the vicinity of the entire amount by the second predetermined amount, similarly to the first embodiment, the protrusion 53 of the WS lever 50 contacts the outer peripheral surface of the first cam 86, The WS lever 50 is held in the first inoperative position. For this reason, the claw 52 of the WS lever 50 is separated from the inner teeth 108 of the bearing cover 100 and the rotation of the steering wheel 40 in the webbing pull-out direction is not prevented. Thereby, the operation state of the automatic lock mechanism is switched to the state in which the emergency lock mechanism can be operated.

Further, after the occupant releases the fastening between the tongue and the buckle from the webbing wearing state, the webbing is wound by the spring force of the winding device 2. Then, the protrusion 53 of the WS lever 50 contacts the first cam 86 from before the winding is completed to when the winding is completed, and the WS lever 50 is held at the first inoperative position. Further, the locking member pop-out preventing projection 54 of the WS lever 50 is engaged with the wall surface 8 a of the cam groove 8 of the spindle 1, and the lock dock 20 is held at a position where it cannot be engaged with the internal teeth 11 of the frame 10. The As a result, it is possible to prevent end lock due to malfunction of the webbing acceleration sensing means and to prevent end lock of the lock dock 20 itself.
In addition, since the operation | movement at the time of the collision of the vehicle, etc. in webbing mounting | wearing state is the same as that of the first embodiment, explanation is omitted.

As described above, also in the seat belt retractor of the present embodiment, the operation and release operation of the automatic locking mechanism can be controlled by the control plate 80, and a compact configuration can be maintained.
Specifically, the webbing acceleration sensing means of this embodiment includes a WS lever 50 having a claw 52 and a WS projection 53, and the automatic locking mechanism includes an ALR projection 62 and an abutment arm 65. The ALR lever 60 and the ALR spring 69 are provided, and the control plate 80 includes first and second cams 86 and 187.

When the webbing is fully pulled out and the ALR lever 69 snaps to the second operating position by the second cam 187, the abutting arm portion 65 abuts the WS lever 50, and the WS lever 50 The claw 52 is engaged with the internal teeth 108 of the bearing cover 100 to prevent the steering wheel 40 from rotating in the webbing pull-out direction.
In addition, when the webbing is wound up by the second predetermined amount, the second cam 187 controls the ALR lever 60 to snap to the second non-operating position by abutting against the ALR projection 62. The first cam 86 controls the WS lever 50 to be held at the first inoperative position by contacting the WS protrusion 53. As a result, the rotation of the steering wheel in the webbing pull-out direction is not prevented, and the operation release operation of the automatic lock mechanism is reliably performed.

  Further, according to the seat belt retractor of the present embodiment, the end lock due to malfunction of the lock dock 20 itself is prevented without having a cancel lever, so that the number of parts can be further reduced and a compact configuration can be achieved. realizable.

In addition, this invention is not limited to embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably.
The control plate of the present invention may be rotated at a different number of rotations according to the rotation of the spindle, may be a speed-increasing rotation as in the present embodiment, or a rib-shaped cam of the control plate is appropriately designed. By doing so, it may be decelerated.

  In addition, the control plate of the present invention controls the swing of the WS lever and the ALR lever and the movement control of the cancel cap by the rib. However, these controls are performed by forming a cam groove in the control plate. Also good.

  Furthermore, each cam of the control plate of the present invention can exhibit the function of each cam described above, and can have the shape of this embodiment as long as it does not unnecessarily interfere with the swinging and movement of each protrusion. It is not limited.

DESCRIPTION OF SYMBOLS 1 Spindle 2 Spring type winding device 6 Drive gear 7 Idle gear 8 Cam groove 8a Wall surface (protrusion prevention part)
10 Frame 20 Lock dock (lock member)
30 Ratchet wheel (latch member)
40 Steering wheel 50 WS lever (first locking means)
53 WS protrusion 54 Lock member protrusion prevention protrusion 60 ALR lever (second locking means)
62 Cam pin (projection for ALR)
70 Inertial body 80 Control plate 81 Driven gear 86 First cam 87, 187 Second cam 90 Cancel lever (cancellation member)
91 Locking member projection 110 Car body acceleration sensing means 120 VS sensor lever

Claims (7)

A spindle that is rotatably supported by the frame and on which the webbing is wound,
A locking member that locks rotation of the spindle in the webbing pull-out direction by engaging with the frame;
A steering wheel that is rotatably supported by the spindle and that operates the lock member by causing a rotation delay with respect to the spindle;
First locking means pivotally supported on the steering wheel is provided, and when the webbing is pulled out at a predetermined speed or more, the first locking means is displaced to the first operating position. Webbing acceleration sensing means for preventing rotation of the steering wheel in the webbing pull-out direction;
A control plate that rotates at a different speed from the spindle according to the rotation of the spindle;
With
The first locking means is controlled by the control plate so as to be held at a first non-operating position where rotation of the steering wheel in the webbing pull-out direction is not blocked when the winding of the webbing is completed, and,
The first locking means is held in the first non-operating position when the webbing winding is completed, thereby preventing a delay in the rotation of the steering wheel with respect to the spindle, and the locking member and the frame. A retractor for a seat belt, wherein the seat belt retractor is held at an unlocked position where it is not engaged. The webbing acceleration sensing means is supported at one end by the steering wheel and at the other end by the first locking means, with the first locking means facing the first inoperative position. Further comprising a biasing means for WS
The first locking means includes a claw portion that is engageable with an inner tooth formed on an inner peripheral surface of a cover member attached to the frame, and a WS for extending in an axial direction toward the control plate. A protrusion, and a protrusion for preventing the lock member from protruding in the axial direction toward the spindle,
The control plate has a WS cam for controlling the first locking means to be held in the first inoperative position by contacting the WS protrusion when the webbing is completely wound. And
Between the spindle and the steering wheel, the steering wheel is biased against the spindle so that the lock member is held in the unlocked position and the spindle and the steering wheel rotate together. Means are provided,
A cam groove is formed on the side surface of the spindle to accommodate the protrusion for preventing the lock member from popping out,
The cam groove prevents the lock member from jumping out of the unlocked position when the first locking means is held in the first inoperative position when the winding of the webbing is completed. The retractor for a seat belt according to claim 1, further comprising a protrusion prevention portion that engages with the protrusion prevention protrusion portion. A second locking means pivotally supported by the steering wheel, wherein the second predetermined amount is wound after the webbing is pulled out for a second predetermined amount. An automatic locking mechanism for displacing the locking means to the second operating position and preventing rotation of the steering wheel in the webbing pull-out direction;
The second locking means is held by the control plate at the second operating position from when the webbing is pulled out by the first predetermined amount until it is wound up by the second predetermined amount. The seatbelt retractor according to claim 1 or 2, wherein the seatbelt retractor is controlled. The automatic locking mechanism further includes ALR biasing means having one end supported by the steering wheel and the other end supported by the second locking means,
The first locking means includes a claw portion that is engageable with an inner tooth formed on an inner peripheral surface of a cover member attached to the frame, and a WS for extending in an axial direction toward the control plate. A protrusion, and
The second locking means has an ALR projection extending in the axial direction toward the control plate, and an abutting arm part capable of contacting the first locking means,
A WS cam for controlling the first locking means to be held in the first inoperative position by contacting the WS protrusion when the webbing is completely wound; When the webbing is pulled out by the first predetermined amount, the second locking means snaps to the second operating position beyond the dead point of the ALR biasing means by contacting the ALR protrusion. An ALR cam to be operated,
When the second locking means snaps to the second operating position, the abutting arm portion comes into contact with the first locking means, and the claw portion of the first locking means is moved. Engage with the inner teeth of the cover member to prevent rotation of the steering wheel in the webbing pull-out direction,
The WS cam contacts the WS protrusion when the webbing is pulled out for the second predetermined amount after the first predetermined amount is pulled out, and the first locking means is the first locking means. The second locking means is controlled to be held in the non-actuated position. At this time, the second locking means is brought into contact with and pressed against the abutting arm portion. 4. The seatbelt retractor according to claim 3, wherein the arm portion snaps beyond the dead point of the ALR biasing means to a second non-actuating position away from the first locking means. 5. . The lock member is provided with a pin portion that penetrates a cam hole formed in the steering wheel,
A cancel lever having a long hole into which the pin portion penetrating the cam hole is inserted and a projection for a lock member extending in the axial direction toward the control plate is swingable on the steering wheel. Supported by
5. The ALR cam of the control plate constitutes a lock member cam that controls the lock member so that it cannot be engaged with the frame when the winding of the webbing is completed. Seat belt retractor. The automatic locking mechanism further includes ALR biasing means having one end supported by the steering wheel and the other end supported by the second locking means,
The first locking means includes a claw portion that is engageable with an inner tooth formed on an inner peripheral surface of a cover member attached to the frame, and a WS for extending in an axial direction toward the control plate. A protrusion, and
The second locking means has an ALR projection extending in the axial direction toward the control plate, and an abutting arm part capable of contacting the first locking means,
A WS cam for controlling the first locking means to be held in the first inoperative position by contacting the WS protrusion when the webbing is completely wound; When the webbing is pulled out by the first predetermined amount, the second locking means snaps to the second operating position beyond the dead point of the ALR biasing means by contacting the ALR protrusion. When the webbing is wound up by a second predetermined amount, the second locking means is brought into contact with the ALR protrusion when the webbing is wound up by the second predetermined amount, and the dead end of the ALR biasing means is exceeded. An ALR cam that causes the arm portion to snap to a second non-actuated position away from the first locking means;
When the webbing is pulled out by the first predetermined amount and the second locking means snaps to the second operating position, the abutting arm portion contacts the first locking means, Engaging the claw portion of the first locking means with the internal teeth of the cover member to prevent rotation of the steering wheel in the webbing pull-out direction;
When the webbing is wound up by the second predetermined amount, the ALR cam is brought into contact with the ALR projection to cause the second locking means to snap to the second inoperative position. The WS cam is controlled so that the first locking means is held in the first non-operating position by contacting the WS protrusion and the WS cam. 4. The seat belt retractor according to claim 3, wherein rotation in the pull-out direction is not prevented. A gear speed increasing mechanism having a drive gear that rotates integrally with the spindle, a driven gear that has fewer teeth than the drive gear that rotates integrally with the control plate, and an idle gear that meshes with both the drive and the driven gear. Further comprising
The seat belt retractor according to any one of claims 1 to 6, wherein the control plate rotates at a speed higher than that of the spindle by the gear speed increasing mechanism.

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