Seat belt retractors

Abstract

[Task] In the belt retractor for a safety belt, at the time of releasing the lock of the unwinding of the belt webbing by a smaller wound amount of belt webbing than conventional to quickly release the lock. [Solution] In a seat belt retractor having a locking mechanism that prevents the reel from rotating in the unwinding direction, a ratchet gear 7 and a lock 30 that rotate integrally with the reel, a clutch 50 that shifts the ratchet 9, which is in the disengaged position with the ratchet gear 7, to the engaged position with the ratchet gear 7, a clutch biasing component that biases the clutch 50 in the winding direction and the unwinding direction, and a link mechanism that connects the clutch 50 to the lock 30, wherein by maintaining the winding bias direction of the clutch 50 in the unwinding direction when the webbing is locked, the wound amount of the webbing when the lock is released is reduced compared to before, and the lock is released quickly.

Description

[Technical field]

[0001] The present invention relates to a belt retractor for safety belts in which the webbing of the safety belt is wound onto a reel. [Technical background]

[0002] A vehicle, such as a motor vehicle, is generally equipped with a safety belt device that includes a belt retractor to protect the occupants sitting in the seats. The belt retractor has a reel for unwinding or rewinding a belt webbing (seat belt) and a locking mechanism that prevents the reel from rotating in the unwinding direction of the belt webbing in an emergency situation (e.g., a collision) depending on the acceleration and inclination of the vehicle or the acceleration of the unwinding of the belt webbing (seat belt).

[0003] In an emergency situation, the belt retractor triggers the locking mechanism, blocks (or prevents) the belt from unwinding through the reel, and holds the occupant who has fastened the belt in the seat and prevents them from being thrown forward.

[0004] The release of this blocking of the unwinding of the webbing is carried out by using the function of winding the webbing by the belt retractor (cf. JP 2012 - 232 727 A), according to which the roller winds up the webbing when the blocked webbing is temporarily loosened (when the force in the unwinding direction is loosened).

[0005] Specifically, in an emergency situation, a locking mechanism integrally connected to the reel (winding axis of the belt webbing) of the seat belt retractor (hereinafter referred to as the belt retractor), which rotates in the direction of belt unwinding, is connected to a clutch. If, as a result of the connection, the clutch rotates in the direction of belt unwinding, a pawl, in conjunction with the rotation of the clutch, moves in the direction of belt unwinding and engages a pawl gear integrally connected to the reel. This prevents the reel (winding axis) of the belt unwinder from rotating in the unwinding direction.

[0006] To release the pawl from the locked state while it is engaged with the ratchet gear, the lock must be released from the clutch. Specifically, when the webbing is wound up, the reel rotates in the winding direction of the webbing, and the clutch, biased in the winding direction by a return spring, rotates integrally with the lock in the winding direction of the webbing. As the clutch rotates, the pawl rotates in the direction of disengagement from the ratchet gear (disengaging direction). The clutch rotation stops when the pawl returns to its initial position (disengaging position). Afterward, the reel continues to wind up the webbing and rotates the lock in the winding direction of the webbing. Therefore, the lock is released from the clutch by rotating the lock relative to the clutch.Therefore, the amount of rotation of the reel from the start to the end of the unlocking of the locking mechanism is greater than the amount of rotation of the reel from the start to the end of the locking operation of the locking mechanism, so a webbing of a corresponding length must be wound up. In a conventional belt retractor, rapid unlocking of the locking mechanism is therefore problematic. When it is difficult to wind up the webbing required to release the lock from the clutch, such as in the case where a sudden stop of the reel with the webbing fully accommodated by the clutch engaging the lock during unwinding of the webbing causes an end lock to prevent the reel from rotating in the direction of unwinding the webbing, releasing the end lock is problematic.Furthermore, if the locking mechanism has been inadvertently triggered during normal use by the acceleration of the vehicle or movements of the occupant, the release of a belt unwinding block may take a correspondingly long time due to the large winding length of the belt, so that the release operation is perceived as annoying.

[0007] DE 11 2014 000 484 T5 describes a seatbelt pretensioner. When a final locking action occurs in a seatbelt pretensioner due to the retraction of a belt webbing, the final locking action is released. A stop member engages a locking arm, which is displaced in a locking operation direction, and stops the locking arm. A locking mechanism, in a state where the locking arm is stationary on the stop member, starts operation with rotation in a pull-out direction of a retractor drum and stops rotation of the retractor drum. A transmission mechanism transmits rotation of the retractor drum to the locking arm and displaces the locking arm in a release direction to release engagement with the stop member between the time the operation of the locking mechanism is started and the time the rotation of the retractor drum is stopped.A release means releases the engagement between the locking arm and the stop member through the transmission mechanism.

[0008] WO 2013 / 133 071 A1 describes a locking mechanism unit for stopping, in an emergency, the rotation of a winding drum in the direction in which a webbing is unwound.The locking mechanism unit includes: a link mechanism that connects a clutch to a locking gear in an emergency, rotates the clutch and the locking gear together in the direction in which the webbing is unwound, engages a pawl with a ratchet gear, and also allows the connection between the clutch and the locking gear to be released by rotating the locking gear relative to the clutch in the direction in which the webbing is wound; and a rotation difference transmission mechanism that, when the clutch and the locking gear are rotated in the connected state in the direction in which the webbing is wound, causes the rotation of the clutch in the direction in which the webbing is wound to be decelerated relative to the rotation of the locking gear in the direction in which the webbing is wound.

[0009] US 2011 / 0 174 911 A1 describes a belt retractor with a locking mechanism. A peripheral wall extends from an edge portion of a through hole formed on a sensor gear constituting the locking mechanism toward a connecting member, and a guide hole is formed on a bottom wall formed at the front end of the peripheral wall. An engaging pin of the connecting member passes through the guide hole from the base end portion, not from the front end portion thereof in the projecting direction. Furthermore, on the front end side of the engaging pin passing through and projecting from the guide hole, the outer peripheral portion is spaced from the inner peripheral portion of the peripheral wall.

[0010] US 2011 / 0 127 363 A1 describes a belt retractor comprising a spool and a locking unit having a locking unit main body with a rotational acceleration detecting unit, wherein the rotational acceleration detecting unit comprises a second rotating body; a rotation transmitting member provided on the second rotating body; an inertia mass body having a pressing portion and provided on the second rotating body; a biasing device provided on the second rotating body;and a holding portion provided on the second rotary body for clamping the rotation transmission member together with the inertia mass body biased by the biasing means, thereby holding the rotation transmission member in a state where the rotation transmission member is not engaged with the first rotary body, and for releasing the mounting of the rotation transmission member when relative rotation is generated between the second rotary body and the inertia mass body.; [Overview of the invention][Problems to be solved by the invention]

[0011] The present invention has been made taking into account the conventional problems and has an object to quickly release the blockage of the unwinding of the webbing by winding up the webbing in a smaller amount than conventionally. [Means of solving the problems]

[0012] The above object is achieved by a belt retractor according to claim 1 and a belt retractor according to claim 7. Claims 2 to 6 describe particularly advantageous implementations of the belt retractor according to claim 1. [Effects of the invention]

[0013] According to the present invention, when releasing the lock of unwinding the webbing, the lock can be released quickly by winding up a smaller amount of webbing than conventionally. [Simple explanation of the drawings] [ Fig. 1] Fig. 1 are perspective views of an entire belt retractor of a first embodiment, seen from different directions. [ Fig. 2] Fig. 2 is a perspective view of a belt retractor pulled apart into different units, from a different direction than in Fig. 3 considered. [ Fig. 3] Fig. 3 is a perspective view of a belt retractor pulled apart into different units, from a different direction than in Fig. 2 considered. [ Fig. 4] Fig. 4 is an exploded perspective view of a housing unit. [ Fig. 5] Fig. 5A is an illustration of a pawl and Fig. 5B shows a representation of a return plate. [ Fig. 6] Fig. 6 is a front view showing a pawl and a pawl gear. [ Fig. 7] Fig. 7 are exploded perspective views of a clock spring unit, seen from different directions. [ Fig. 8A] Fig. Fig. 8A is an exploded perspective view of a blocking unit forming a blocking mechanism and a ratchet gear, from a direction other than Fig. 9A is considered. [ Fig. 8B] Fig. Figure 8B is a perspective view of a barrier, from a different direction than in Fig. 8A is considered. [ Fig. 9A] Fig. 9A is an exploded perspective view of a locking unit forming a locking mechanism and a ratchet gear, from a direction other than Fig. 8A is considered. [ Fig. 9B] Fig. 9B is a perspective view of a coupling, from a different direction than in Fig. 9A is considered. [ Fig. 10] Fig. 10 is a cross-sectional view of a roller unit. [ Fig. 11] Fig. 11 is a sectional view showing a locking mechanism of the first embodiment in an unlocked state. [ Fig. 12] Fig. 12 is a partial sectional view of a belt retractor of the first embodiment in the unblocked state. [ Fig. 13] Fig. 13 is a partial sectional view of a belt retractor of the first embodiment, illustrating the transition state from the unblocked state to the blocked state. [ Fig. 14] Fig. 14 is a partial sectional view of a belt retractor of the first embodiment, illustrating the transition state from the unblocked state to the blocked state. [ Fig. 15] Fig. 15 is a partial sectional view of a webbing retractor of the first embodiment, illustrating the transition state from the unblocked state to the blocked state. [ Fig. 16] Fig. 16 is a partial sectional view of a belt retractor of the first embodiment in the blocked state, including a blocking mechanism. [ Fig. 17] Fig. 17 is a partial sectional view of a belt retractor of the first embodiment, illustrating the transition state from the locked state to the unlocked state. [ Fig. 18] Fig. 18 is a partial sectional view of a belt retractor of the first embodiment, illustrating the transition state from the locked state to the unlocked state. [ Fig. 19] Fig. 19 is a partial sectional view of a webbing retractor of the first embodiment, illustrating the transition state from the locked state to the unlocked state. [ Fig. 20] Fig. 20 is a partial sectional view of a belt retractor of the first embodiment, illustrating the transition state from the locked state to the unlocked state. [ Fig. 21] Fig. 21 is a partial sectional view of a belt retractor of the first embodiment in the unblocked state. [ Fig. 22] Fig. 22 is a partial sectional view of a belt retractor of a second embodiment in the unblocked state. [ Fig. 23] Fig. 23 is a partial sectional view of a belt retractor of the second embodiment, illustrating the transition state from the unblocked state to the blocked state. [ Fig. 24] Fig. 24 is a partial sectional view of a belt retractor of the second embodiment in the blocked state. [ Fig. 25] Fig. 25 is a partial sectional view of a belt retractor of the second embodiment, illustrating the transition state from the locked state to the unlocked state. [ Fig. 26] Fig. 26 is a partial sectional view of a belt retractor of a third embodiment in the unblocked state. [ Fig. 27] Fig. 27 is a partial sectional view of a belt retractor of the third embodiment in the transition state from the unblocked state to the blocked state. [ Fig. 28] Fig. 28 is a partial sectional view of a belt retractor of the third embodiment in the blocked state. [ Fig. 29] Fig. 29 is a partial sectional view of a belt retractor of the third embodiment, illustrating the transition state from the locked state to the unlocked state. [ Fig. 30] Fig. 30 is a partial sectional view of a modified example of a webbing retractor of the first embodiment in an unblocked state. [ Fig. 31] Fig. 31 is a partial sectional view of a modified example of a webbing retractor of the first embodiment in the transition state from the unblocked state to the blocked state. [ Fig. 32] Fig. 32 is a partial sectional view of a modified example of a webbing retractor of the first embodiment in the locked state. [Embodiments of the present invention]

[0014] As mentioned above, the characteristic of the present invention is that a webbing unwinding lock (rotation of the reel in the webbing unwinding direction) can be released by winding up a smaller amount of webbing than conventional ones. Therefore, in the present invention, the clutch is biased to rotate in the webbing unwinding direction by a return spring in the locked state, and during unblocking, according to the webbing unwinding (rotation of the reel in the webbing winding direction), after the connection of the lock to the clutch is released, the direction of the clutch biased to rotate by the return spring changes from the webbing unwinding direction to the winding direction. This releases the connection of the lock to the clutch at an early stage of unblocking.

[0015] In the following, embodiments of the seat belt retractor of the present invention (hereinafter referred to as seat belt retractor) will be explained.

[0016] A seat belt retractor 100 of the present embodiment is a webbing 2 winding device for winding a seat belt webbing, which is provided on a seat belt device for vehicles. The seat belt device including the retractor 100 is mounted in a vehicle, and an occupant sitting on a seat is restrained by the webbing 2 (seat belt). (First embodiment)

[0017] Fig. 1A and Fig. 1B are perspective views of the entire belt retractor 100 of the first embodiment, viewed from different directions. Fig. 2 and Fig. 3 are also perspective views of the belt retractor 100 pulled apart into several units, viewed from different directions.

[0018] The belt retractor 100 has, as shown in Fig. 1, a housing unit 3, a roller unit 4, a coil spring unit 5 and a blocking unit 6.

[0019] The housing unit 3 has, as in Fig. 2 and Fig. 3, a housing 3A, an acceleration sensor 15, a pawl 9 with an engagement claw 9A and a return plate 18. The housing 3A accommodates a roller 10 and simultaneously serves as a fastening part for fastening the belt retractor 100 to the vehicle.

[0020] The roller unit 4 includes a roller 10 for winding the webbing 2, and a ratchet gear 7, which is a constituent element of a locking mechanism 8 explained later. The roller 10 has a pair of end portions 11, 12 (first end portion 11, second end portion 12) and a winding portion 13 between the first end portion 11 and the second end portion 12, and rotates around a center line C1. The webbing 2 is attached to the winding portion 13, so that the webbing 2 is wound onto the winding portion 13.

[0021] The ratchet gear 7 has a plurality of teeth (ratchet teeth) 7A and is arranged on the first end part 11 of the roller 10 so that it rotates and stops together with the roller 10.

[0022] The coil spring unit 5 has a coil spring 70 ( Fig. 7), the roller 10 (roller unit 4) always tensions in the winding direction W of the belt 2 ( Fig. 6) and winds the webbing 2 onto the reel 10. The webbing 2 is wound onto the reel 10, which rotates in the winding direction W, and accommodated in the belt retractor 100, and is unwound from the belt retractor 100 as the reel 10 rotates in a direction P unwinding the webbing 2.

[0023] The blocking unit 6 comprises, for example, a mechanism cover 48, a lock 30 ( Fig. 8A) and a clutch 50 explained later. The blocking unit 6 is adjacent to the ratchet gear 7 of the reel unit 4 and, together with the ratchet gear 7, forms the blocking mechanism 8, which prevents rotation of the reel 10 in the unwinding direction P.

[0024] The locking mechanism 8 is triggered according to (or in response to) the acceleration of the unwinding of the webbing 2 or the acceleration of the vehicle, whereby the (engaging claw 9A of the) pawl 9 engages the pawl teeth 7A of the pawl gear 7, preventing rotation of the pawl gear 7, thereby preventing (blocking) rotation of the reel unit 4 (reel 10).

[0025] The winding spring unit 5 and the blocking unit 6 are respectively fixed to the first side wall 22 and the second side wall 23 of the housing unit 3, wherein the roller unit 4 accommodated in the housing unit 3 is held rotatably in the webbing winding direction W and unwinding direction P.

[0026] Next, the above-mentioned respective units of the belt retractor 100 will be explained in more detail. "Housing unit"

[0027] Fig. 4 is an exploded perspective view of the housing unit 3.

[0028] The housing unit 3 has, as shown in Fig. 4, a housing 3A in which the roller 10 is housed, a protection 46 for the webbing 2, an acceleration sensor 15, a sensor cover 39 covering the acceleration sensor 15, the pawl 9, a pawl rivet 20, the return spring 19 and the return plate 18. "Housing"

[0029] The housing 3A has a rear wall 21 fixed to the body, side walls 22, 23 (first side wall 22 and second side wall 23) adjacent to the two sides of the rear wall 21, and two mounting plates 24 fixed between the side walls 22, 23. The guard 46 has a slot 46A through which the belt webbing 2 passes and is attached to a bracket 47.

[0030] The housing 3A has an opening formed in the first side wall 22 (first opening 25), a pawl housing 25A to which the first opening 25 is connected, and an opening formed in the second side wall 23 (second opening 26). The pawl gear 7, which is arranged on the first end part 11 of the roller 10, is arranged in the first opening 25 of the housing 3A, and the second end part 12 of the roller 10 is arranged in the second opening 26, so that the roller unit 4 (roller 10) is housed in the housing 3A. “pawl”

[0031] A perspective view of the pawl 9 is shown in Fig. 4. Furthermore, Fig. 5A is a front view of the pawl 9, the pawl 9 having a pair of engaging claws 9A engaging the pawl teeth 7A of the pawl gear 7, a guide pin 9B formed on one edge side near the engaging claws 9A, and a cylindrical boss 9C formed on the other edge side remote from the engaging claws 9A of the pawl 9.

[0032] The guide pin 9B is inserted into a through hole 18C of the return plate 18 (explained later) as well as into a guide groove 56 of the coupling 50 ( Fig. 9A). The projection 9C is further inserted as in Fig. 4, is inserted from the inside of the housing 3A into a fastening opening 29 of the first side wall 22, so that the front end of the pawl rivet 20 is pressed from the outside of the first side wall 22 of the housing 3A into the fastening opening of the projection 9C. As a result, the pawl 9 is rotatably fastened about the projection 9C inserted into the first side wall 22.

[0033] Fig. 6 is a front view illustrating the pawl 9 and the pawl gear 7. In the figure, a solid line shows the pawl 9 rotated to the engaging position, and a dashed line shows the pawl 9 rotated to the disengaging position.

[0034] When the locking mechanism 8 is triggered, along with the clutch 50 rotating in the direction P unwinding the webbing 2 around a center line C1 as the center, as explained later, the pawl 9 is forcibly guided so that the engaging claws 9A rotate around a center line C2 (lug 9C) as the center from the disengaging position not engaged with the pawl teeth 7A to the engaging position at which the engaging claws 9A engage the pawl teeth 7A. “Return spring”

[0035] Back to Fig. 4. The return spring 19 is a torsion spring in which the first arm part 19A and the second arm part 19B, which are located on both sides of a connecting spring 19C, are formed in an approximately V-shape when viewed from the front. The first arm part 19A is, as explained later, fixed to a fixing pin 59 ( Fig. 9B), and the second arm part 19B is attached to a fixing pin 18E of the return plate 18.

[0036] In the return spring 19, due to the relative angle change of the first arm part 19A and the second arm part 19B in the circumferential direction of the connecting spring 19C, the connecting spring 19C is elastically torsionally deformed in the winding direction. “Return plate”

[0037] The return plate 18 has, as shown in Fig. 5B, a round plate 18A and an approximately triangular arm part 18B extending from the round plate 18A, wherein a mounting opening 18D is provided coaxially in the round plate 18A and a through hole 18C is provided at the front end of the arm part 18B, into which the guide pin 9B of the pawl 9 is inserted. Furthermore, the fastening pin 18E is attached vertically to the periphery of the round plate 18A, to which the second arm part 19B of the return spring 19 is attached.

[0038] By inserting the guide pin 9B of the pawl 9 into the through hole 18C and inserting the head part 20A of the pawl rivet 20 into the mounting opening 18D, the return plate 18 is rotatably assembled with the pawl 9. “Accelerometer”

[0039] The acceleration sensor 15 is an emergency situation blocking triggering device which detects the acceleration of the vehicle in an emergency situation of the vehicle and triggers the blocking mechanism 8, and has, as shown in Fig. 4, a sensor holder 15A, an inertia body 15B, and a sensor lever 15C. The inertia body 15B is a spherical metal body arranged in the recess of the sensor holder 15A and movably held between the sensor holder 15A and the sensor lever 15C. The sensor lever 15C covers the inertia body 15B from above and is attached to the sensor holder 15A so that it can move up and down.

[0040] The acceleration sensor 15 is inserted into the sensor cover 39, and the sensor holder 15A is fixed to the sensor cover 39. The sensor cover 39 is fixed to the first side wall 22 by inserting it into the mounting hole 28 of the first side wall 22 of the housing 3A. In this state, a locking claw 15D of the sensor lever 15C is positioned outside the sensor cover 39, projecting upward.

[0041] Due to the emergency situation of a vehicle (e.g., a collision or emergency braking), in the event that the acceleration of the vehicle exceeds a certain value, the mass inertia body 15B moves on the sensor holder 15A by the inertial force and pushes the sensor lever 15C upward in the drawing (see. Fig. 30). That is, the acceleration sensor 15 detects the acceleration of the vehicle due to the movement of the inertia body 15B, moves the locking claw 15D of the sensor lever 15C upwards so that it engages the engagement pawl 60 ( Fig. 30) upwards and the engaging pawl 60 engages the teeth 34 of a ratchet wheel 35.

[0042] Furthermore, the engagement pawl 60 engages the teeth 34 of the ratchet wheel 35, connecting the lock 30 to the clutch 50. “ratchet gear”

[0043] As in Fig. 2 and Fig. As shown in Fig. 8A, the ratchet gear 7 has ratchet teeth 7A, a ratchet base 7B, and a shaft portion (ratchet shaft portion) 7C formed at the center of the ratchet base 7B. The plurality of ratchet teeth 7A are formed on the entire outer periphery of the ratchet gear 7.

[0044] In an emergency situation of the vehicle, according to the acceleration of the vehicle or the acceleration of the unwinding of the webbing 2, the clutch 50 rotates in the unwinding direction P due to the unwinding of the webbing 2, as explained later. By rotating the clutch 50 in the unwinding direction P, the pawl 9 moves (rotates) to the engaging position, and the engaging claw 9A of the pawl 9 engages the pawl teeth 7A of the pawl gear 7. Thereby, the rotation of the pawl gear 7 is blocked, and rotation of the pawl gear 7 (rotation of the reel unit 4) in the unwinding direction is prevented.

[0045] Incidentally, the pawl 9 and the pawl gear 7 engage only when the pawl gear 7 rotates in the unwinding direction P, so that the pawl teeth 7A of the pawl gear 7 and the engaging claw 9A of the pawl 9 only prevent the pawl gear 7 from rotating in the unwinding direction P. When the engaging claw 9A is removed from the pawl teeth 7A, the connection of the pawl 9 with the pawl gear is released. “Clock spring unit”

[0046] Fig. 7A and Fig. 7B are exploded perspective views of the clock spring unit 5 viewed from different directions.

[0047] The coil spring unit 5 has a coil spring 70, a spring housing 71, a spring leaf 72, and a cylindrical spring shaft 73. An outer end K1 of the coil spring 70 is fixed to a fixing part 74 of the spring housing 71, and an inner end K2 of the coil spring 70 is fixed to the spring shaft 73. The coil spring 70 and the spring shaft 73 are housed in the spring housing 71.

[0048] The spring leaf 72 is fixed to the spring housing 71 and covers the coil spring 70 and the spring shaft 73 in the spring housing 71. Furthermore, the spring leaf 72 has a circular recess 75 formed in the center and a bearing hole 76 formed in the center of the recess 75. One end of the spring shaft 73 is disposed in the recess 75 of the spring leaf 72 and is rotatably supported by the spring leaf 72. The other end of the spring shaft 73 is rotatably supported by a pin 77 of the spring housing 71.

[0049] A shaft 17 of the roller 10 is fixed to the spring shaft 73 and is inserted into the bearing bore 76, with the spring leaf 72 holding the shaft 17 rotatably.

[0050] The spring shaft 73 rotates integrally with the roller 10 and also transmits the preload force of the spiral spring 70 in the winding direction W to the roller 10.

[0051] The spiral spring 70 of the coil spring unit 5 corresponds to the coil pre-tensioning component of the present invention.

[0052] Due to the above structure, the coil spring unit 5 always pretensions the roller 10 by means of the coil spring 70 in the direction W winding the webbing 2. When the webbing 2 is unwound, the coil spring 70 is wound up by rotating the roller 10 in the unwinding direction P. When the webbing 2 is wound up, the roller 10 rotates in the winding direction W due to the pretensioning force of the coil spring 70, so that the webbing 2 is wound onto the roller 10. “Blocking unit”

[0053] Fig. 8A and Fig. 9A are exploded perspective views of the locking unit 6 and the pawl gear 7, which form the locking mechanism 8, viewed from different directions. Fig. 9B is a perspective view illustrating the clutch 50.

[0054] The locking unit 6 has the mechanism cover 48, the lock 30, a locking arm 40, a sensor spring 45, the clutch 50 and the engaging pawl 60, and is provided on the first side wall 22 of the housing 3A. “Mechanism cover”

[0055] The mechanism cover 48 has, as shown in Fig. 9A, a first housing part 48A, in which, for example, the lock 30, the blocking arm 40 and the clutch 50 are housed, a second housing part 48B, in which the acceleration sensor 15 is housed, and a cylindrical bearing projection 48C.

[0056] The blocking claw 15D of the sensor lever 15C of the acceleration sensor 15 is arranged in a bore 48D of the second housing part 48B and protrudes through the bore 48D into the first housing part 48A. “Blocking”

[0057] Fig. Figure 8B is a perspective view showing the lock 30.

[0058] The lock 30 has a shaft opening 31 formed in the middle ( Fig. 9A), several projections 32 ( Fig. 9A), which extend into the several recesses 7F ( Fig. 8A) of the pawl gear 7, a shaft part (gear shaft part) 33 projecting from the center and a ratchet wheel 35 having a plurality of teeth 34 on the entire periphery, which is an annular component formed on the outer circumference of the lock 30.

[0059] The lock 30 has a column-shaped support part 36 ( Fig. 8A) for the arm (blocking arm 40), a support pin 37 which supports the sensor spring 45, and a stopper 38 which restricts the rotation of the blocking arm 40 explained later.

[0060] Into the shaft opening 31 of the lock 30 ( Fig. 9A), the pawl shaft part 7C of the pawl gear 7 is inserted, and the plurality of projections 32 of the lock 30 are inserted into the plurality of recesses 7F of the pawl gear 7. Thus, the lock is fixed to the pawl gear 7 and rotates integrally with the roller unit 4 (roller 10).

[0061] On the other hand, the gear shaft part 33 of the lock 30 is pushed into the bearing boss 48C of the mechanism cover 48 and rotatably held by the bearing boss 48C. “Blocking arm”

[0062] The blocking arm 40 has, as in Fig. 8A and Fig. 9A, an insertion hole 43 provided between one end portion 41 of the longitudinal direction formed in a curved shape and the other end portion 42, and a support pin 44 supporting the sensor spring 45. The locking arm 40 is rotatably connected to the lock 30 on the inside of the ratchet wheel 35 around the arm support portion 36 as the center by inserting the arm support portion 36 of the lock 30 into the insertion hole 43.

[0063] The sensor spring 45 is arranged between the support pin 44 of the blocking arm 40 and the support pin 37 of the lock 30, and biases the other end part 42 of the blocking arm 40 in the opposite direction to the blocking triggering direction explained later (direction of arrow L in Fig. 11). The other end part 42 of the blocking arm 40 rotates due to the pretension of the sensor spring 45 and stops at the stopper 38 ( Fig. 11) adjacent to the barrier 30. "Coupling"

[0064] The coupling 50 is, as in Fig. 8A and Fig. 9A, in the state in which it is located between the lock 30 and the mechanism cover 48, it is rotatably housed in the first housing part 48A within a predetermined rotation range.

[0065] The clutch 50 has, as in Fig. 9A, an annular inner wall 51, a clutch gear 52 formed on the inner circumference of the inner wall 51, an annular outer wall 53 surrounding the inner wall 51 and a central opening 54 positioned in the middle of the inner wall 51. The gear shaft part 33 of the lock 30 ( Fig. 8A) so that the lock 30 and the roller unit 4 are arranged to be rotatable relative to the clutch 50. When a lock is triggered, one end portion 41 of the locking arm 40 engages the engagement teeth of the clutch gear 52.

[0066] The clutch 50 rotates by engaging one end portion 41 of the blocking arm 40 with the engagement teeth of the clutch gear 52, integrally with the lock 30 rotating in the webbing unwinding direction P.

[0067] On the outside of the annular outer wall 53 of the coupling 50 are a guide part 55, an elongated guide groove 56 formed in the guide part 55, a columnar engagement pawl support part 57 ( Fig. 9B), a stopper 58 against which the engagement pawl 60 abuts, and a fixing pin 59 ( Fig. 9B) to which the first arm part 19A of the return spring 19 provided between the guide groove 56 and the engaging pawl support part 57 is attached.

[0068] The guide pin 9B of the pawl 9 is inserted into the guide groove 56, whereby, as will be explained later, the guide pin 9B is guided (forcibly moved) through the guide groove 56 by rotating the coupling 50.

[0069] This allows the clutch 50 and the pawl 9 to rotate together. When the clutch 50 rotates in the unwinding direction P, the pawl 9 rotates in the direction of engagement with the ratchet gear 7 (engagement direction), and when the clutch 50 rotates in the winding direction W, the pawl 9 rotates in the direction of disengagement from the ratchet gear 7 (disengagement direction). That is, the clutch 50 rotates together with the pawl 9 between a first position where the pawl 9 is in a disengaging position and a second position where the pawl 9 is in an engaging position. “Engagement pawl”

[0070] The engagement pawl 60 has, as in Fig. 8A and Fig. 9A, a cylindrical fixing member 61 rotatably supported by the engaging pawl support member 57 of the clutch 50, and an engaging claw 62 engaging the teeth 34 of the ratchet wheel 35.

[0071] When the engagement pawl 60 rotates under its own weight, the engagement pawl 60 hits the stopper 58 of the clutch 50 and stops.

[0072] As already explained with respect to the explanation of the acceleration sensor 15, when the acceleration of the vehicle exceeds a certain acceleration, the engaging pawl 60 is pushed upward by the locking claw 15D, which is pushed by the inertia body 15B and moves upward, and rotates around the fixing part 61 as the center. Through this rotation, the engaging claw 62 of the engaging pawl 60 engages the teeth 34 of the ratchet wheel 35, thus connecting the clutch 50 to the lock 30. “Roller unit”

[0073] Fig. 10 is a sectional view of the roller unit 4.

[0074] The roller unit 4 has, as shown in the figure, the ratchet gear 7, the roller 10, and a columnar torsion bar 14. The ratchet gear 7 has a plurality of ratchet teeth 7A formed on the entire outer periphery of the ratchet gear 7, a projection 7D projecting from the center to the roller 10 side, a mounting hole 7E formed on the projection 7D into which the torsion bar 14 is inserted, and the shaft part (ratchet shaft part) 7C formed in the center.

[0075] The roller 10 has a shaft hole 16 formed along the center line C1 and the shaft 17 formed at the center of the second end portion 12. The shaft hole 16 is closed by the second end portion 12 of the roller 10 and opened by the first end portion 11 of the roller 10. The pawl shaft portion 7C and the shaft 17 are positioned on the center line C1 of the roller 10, and the roller unit 4 is rotatably supported with the center line C1 as the axis. “Torsion bar”

[0076] The torsion bar 14 is connected to the roller 10 and the ratchet gear 7, and is mounted so that it is relatively non-rotatable with respect to the roller 10 and the ratchet gear 7, respectively.

[0077] The torsion bar 14 is made of steel, for example, and is inserted into the shaft hole 16 of the roller 10. One end of the torsion bar 14 is fixed in the shaft hole 16 so as to be relatively non-rotatable with respect to the second end 12 of the roller 10, and the other end of the torsion bar 14 is inserted into the mounting hole 7E of the ratchet gear 7 and fixed so as to be relatively non-rotatable with respect to the projection 7D. The ratchet gear 7 is fixed to the torsion bar 14 and mounted to the first end 11 of the roller 10. Both end portions of the torsion bar 14 are respectively secured, for example, by caulking, so as to prevent them from falling off the roller 10 and the ratchet gear 7. In the normal state, the pawl gear 7 is rotated and stopped together with the roller 10 by the torsion bar 14, and stopping the rotation of the pawl gear 7 stops the rotation of the roller 10.

[0078] The torsion bar 14 is made of an energy-absorbing material and absorbs the kinetic energy of the occupant in an emergency situation in the vehicle. If an occupant who has fastened the belt webbing 2 moves forward in the vehicle while the pawl 9 is stopping the rotation of the pawl gear 7 in the unwinding direction P, the force from the occupant (unwinding load) on the belt webbing 2 increases. The unwinding load is the load acting on the belt webbing 2 due to the occupant's movement. If the unwinding load of the belt webbing 2 exceeds a certain value, the torsion bar 14 is plastically deformed (here, torsional deformation) by the torque of the unwinding direction P acting on the roller 10. The torsion bar 14 rotates the roller 10 in the unwinding direction P while undergoing plastic deformation.In this way, the roller 10 rotates in the unwinding direction P due to the plastic deformation of the torsion bar 14. As a result, the belt webbing 2 is unwound from the roller 10 and the kinetic energy of the occupant is absorbed.

[0079] Next, the locking operation of the webbing retractor 100 of the above-mentioned first embodiment will be explained.

[0080] The stopping of the unwinding of the belt strap due to a sudden unwinding of the belt strap 2 and its release are explained.

[0081] Before this explanation, the arrangement of the blocking mechanism of the belt retractor 100 will first be explained.

[0082] Fig. 11 is a sectional view showing the locking mechanism in the unlocked state (normal state) of the belt retractor 100.

[0083] In Fig. 11, the blocking arm 40 is rotatably connected to the support member for the arm 36 of the lock 30. The preload force of the sensor spring 45 acts on the blocking arm 40 in the opposite direction (counterclockwise in the figure) to the blocking triggering direction (direction of arrow L) around the support member for the arm 36.

[0084] Because the blocking arm 40 is biased by the sensor spring 45, the other end part 42 abuts against the stopper 38 provided on the lock 30, wherein the one end part 41 is held in the state away from the clutch gear 52 of the clutch 50, ie, in the state in which the lock 30 is not connected to the clutch 50.

[0085] Furthermore, in the unblocked state of Fig. 11 the clutch 50 is pre-tensioned by the return spring 19 in the winding direction W, while the guide pin 9B of the pawl 9 ( Fig. 6) by the return spring 19 into the position defined by the pawl gear 7 ( Fig. 6) is preloaded in the disengaging direction. As a result, the guide pin 9B abuts the lower edge of the guide groove 56 of the clutch 50 in the figure, so that the pawl 9 is held in the disengaged position and the clutch 50 is held in the first position.

[0086] If the webbing 2 is unwound in this state with a certain acceleration or slower, the roller 10 and the lock 30 rotate in the unwinding direction P. The clutch 50 is not connected to the roller 10 and the lock 30, so that it does not rotate, and the webbing 2 can be unwound freely without the unwinding of the webbing 2 being blocked.

[0087] On the other hand, if the webbing 2 is suddenly unwound at a rate exceeding the predetermined acceleration, so that the acceleration of the rotation of the reel 10 in the unwinding direction P exceeds a predetermined value, the locking arm 40 can no longer follow the rotation of the reel 10 (and consequently, the lock 30) due to the inertial force. That is, one end portion 41 of the locking arm 40 resists the biasing force of the sensor spring 45, shifts in the lock-initiating direction (direction of arrow L), and engages the clutch gear 52. As a result, the clutch 50 and the lock 30 (reel 10 and ratchet gear 7) rotating in the unwinding direction P are connected, and the clutch 50 resists the biasing force of the winding direction W in the unblocked state of the return spring 19 and rotates in the unwinding direction P.

[0088] When the clutch 50 rotates in the unwinding direction P, the guide pin 9B of the pawl 9 is forcibly guided by the lower edge of the guide groove 56 of the clutch 50 shown in the figure, which rotates around the center line C1, and moves to the center of the clutch 50 (rotates around the center line C2 ( Fig. 4) the fastening hole 29 as the center). By rotating the guide pin 9B, the engagement claw 9A of the pawl 9 engages the pawl teeth 7A of the pawl gear 7 and blocks the rotation of the pawl gear 7. At the same time, it prevents the roller 10, which is integral with the pawl gear 7, from rotating in the unwinding direction P and prevents the webbing 2 from unwinding.

[0089] Incidentally, in the above explanation, the mechanism that connects and releases the coupling 50 to the lock 30, including the locking arm 40 and the sensor spring 45, which connect and release the coupling 50 to the lock 30 by rotating the reel 10 based on the unwinding and winding of the webbing 2, is generically referred to as the connecting mechanism. The connecting mechanism forms part of the locking mechanism.

[0090] Fig. 12 to Fig. 16 are sectional views showing the locking mechanism 8, which illustrates the sequence of operations from unwinding to stopping (from the unlocked state to the locked state) of the webbing 2 in the webbing retractor 100 according to the above-mentioned first embodiment, along with the direction of the spring force of the return spring 19 and the direction of the torque acting on the pawl 9 and the clutch 50.

[0091] In other words, Fig. 12 is a sectional view showing the blocking mechanism 8 in the normal state of the reel, i.e. in the unblocked state.

[0092] As already explained, the first arm part 19A of the return spring 19 is connected to the coupling 50 (fixing pin 59) and the second arm part 19B is connected to the fixing pin 18E of the return plate 18 ( Fig. 4) is connected to the locking pawl 9. The return spring 19 exerts a spring force F1 on the fastening pin 59 of the clutch 50 through the first arm part 19A, and a spring force F2 on the fastening pin 18E of the return plate 18 through the second arm part 19B.

[0093] As from Fig. 12, the spring force F1 of the return spring 19, which acts on the fastening pin 59 of the clutch 50, creates a torque M1 around the center line C1, which is the center of rotation of the clutch 50, so that in the non-blocked state in Fig. 12 the torque M1 acts in the winding direction W.

[0094] Furthermore, the other end part 42 of the blocking arm 40 is held in the abutting state against the stopper 38 by the pretension of the sensor spring 45 (see Fig. 11).

[0095] Next, when in an emergency situation of the vehicle, as in Fig. 13, the webbing 2 is suddenly unwound so that the acceleration of unwinding the webbing 2 exceeds a certain acceleration and the acceleration (acceleration of rotation) of the reel 10 rotating in the unwinding direction P exceeds a certain value, since the blocking arm 40 is rotatably held by the arm support part 36 of the lock 30, as with reference to Fig. 11, the locking arm 40 experiences a deceleration due to inertia in relation to the rotating lock 30. That is, the locking arm 40 rotates around the arm support member 36 as the center while compressing the sensor spring 45, so that, as shown by arrow L in the figure, one end portion 41 of the locking arm 40 moves to the outside of the radial direction of the lock 30 and engages the clutch gear 52 of the clutch 50.

[0096] In this way, the clutch 50 is connected to the lock 30 by the blocking arm 40, so that they rotate together with the lock 30 and the roller 10 in the unwinding direction P, resisting the spring tension F1 (torque M1) acting in the winding direction W of the return spring 19.

[0097] When the clutch 50 rotates, the guide pin 9B of the pawl 9, as shown in Fig. 14, the clutch 50 is forcibly guided by the guide groove 56 of the clutch 50, resisting the biasing force of the return spring 19, so that the engaging claw 9A of the pawl 9 is rotated in the engaging direction (arrow X) in which it engages the pawl teeth 7A of the pawl gear 7. That is, the rotating clutch 50 rotates the pawl 9 from the disengaging position toward the engaging position.

[0098] As a result of the unwinding of the belt webbing 2, the clutch 50 rotates and as a result of the rotation of the pawl 9 in the engaging direction, the pawl 9 and the return plate 18 rotate about the center line C2 of the fastening opening 29 of the first side wall 22 of the housing 3A ( Fig. 4).

[0099] As a result, the direction of the spring force F1 of the return spring 19, ie the direction of the line connecting the fixing pin 59 of the clutch 50 with the fixing pin 18E of the return plate 18, is changed. Consequently, with respect to the torque M1 acting on the clutch 50 around the center line C1 by the spring force F1 of the return spring 19, which torque acts in the winding direction W in the unblocked state, the value acting in the winding direction becomes smaller with the continued unwinding of the webbing 2, and in the state of Fig. 14 the torque M1 becomes zero.

[0100] Fig. Figure 14 shows the state in which the fixing pin 18E of the return plate 18, the fixing pin 59 of the clutch 50, and the rotation center of the clutch 50 (point on the center line C1) are adjacent to each other on a straight line. Consequently, the state in which the spring force F1 acts in the direction toward the rotation center of the clutch 50 and no torque M1 is generated is shown.

[0101] From the state of Fig. 14 now changes the direction of the torque M1 acting on the clutch 50 through the return spring 19 around the center line C1 from the winding direction W to the unwinding direction P of the belt webbing 2.

[0102] Fig. 15 shows the state in which, as a result of the unwinding of the belt webbing 2 (rotation of the roller unit 4 in the unwinding direction P), the direction of the torque M1 acting on the clutch 50 has changed from the winding direction W to the unwinding direction P, and Fig. 16 represents the locked state of the roller unit 4 (roller 10). That is, the pawl 9 is engaged with the pawl teeth 7A of the pawl gear 7.

[0103] In the blocked state, as in Fig. 16, the direction of the torque M1 acting on the clutch 50 due to the return spring 19 is the unwinding direction P.

[0104] On the other hand, the second arm part 19B of the return spring 19 ( Fig. 11) the spring force F2 acts on the fastening pin 18E of the return plate 18, so that the torque M2 acts on the pawl 9 around the center line C2 via the guide pin 9B of the pawl 9, which is inserted into the through hole 18C, through the spring force F2. The direction in which the torque M2 acts on the pawl 9 is as shown in Fig. 12 to Fig. 16, always the direction in which the pawl 9 rotates around the center line C2 in the disengaging direction. This means that the torque M2 always exerts a preload force on the guide groove 56 of the clutch 50 to rotate the clutch 50 in the winding direction W.

[0105] However, the torque M2 becomes smaller as the pawl 9 rotates from the disengaging position to the engaging position, with the torque M2 in the state of Fig. 16, in which the pawl 9 is in the engaging position (in the locked state), hardly occurs. This is because, as the pawl 9 rotates from the disengaging position to the engaging position, the line connecting the fixing pin 59 of the clutch 50 and the guide pin 9B of the pawl 9 approaches the rotation center of the pawl 9 (point on the center line C2).

[0106] This ensures that at least in the blocked state of Fig. 16 with regard to the preload force acting on the clutch 50 by the return spring 19, the preload force in the unwinding direction P due to the torque M1 is greater than the preload force in the winding direction W due to the torque M2.

[0107] In other words, in the course of the change, the state of Fig. 14, in which the torque M1 is zero, into the blocked state of Fig. 16 the torque M1 in the unwinding direction P gradually increases, so that the preload force in the unwinding direction P due to the torque M1 becomes greater than the preload force in the winding direction W due to the torque M2 and the direction of the preload force acting on the clutch 50 from the winding direction W to the unwinding direction P. As a result, the clutch 50 is preloaded in the locked state by the return spring 19 in the unwinding direction P and by this preload force the clutch 50 is held at the second position leading the pawl 9 into the engaging position.

[0108] Next, in order to release the blocking of the rotation of the roller unit 4 (roller 10) in the unwinding direction P by the blocking mechanism 8, it is necessary to remove the tensile force of the unwinding direction P applied to the webbing 2. When the tensile force of the unwinding direction P applied to the webbing 2 is removed, the roller unit 4 (roller 10) and the lock 30, which is integrally attached to the ratchet gear 7 of the roller unit 4, rotate by the pretensioning force of the coil spring 70 of the coil spring unit 5 ( Fig. 7) in the winding direction W.

[0109] Fig. 17 shows the state in which the roller unit 4 rotates slightly in the winding direction W by the biasing force of the coil spring 70 of the winding spring unit 5 to release the lock and the webbing 2 is wound up.

[0110] In this case, the clutch 50 is biased by the return spring 19 in the unwinding direction P and held at the second position in the state leading the pawl 9 to the engaging position, so that it does not rotate in the winding direction W while the lock 30 rotates slightly in the winding direction W.

[0111] When the relative rotation angle created between the lock 30 rotating in the winding direction W and the stationary clutch 50 reaches the relative rotation angle required to disengage one end portion 41 of the lock arm 40 from the clutch gear 52, one end portion 41 of the lock arm 40 rotates due to the biasing force of the sensor spring 45 and moves away from the clutch gear 52, thereby releasing the connection between the clutch 50 and the lock 30.

[0112] On the other hand, as in Fig. 17, when the connection between the clutch 50 and the lock 30 is released, simultaneously or immediately thereafter, by rotating the pawl gear 7 in the winding direction W, the engaging claw 9A of the pawl 9 is disengaged from the pawl teeth 7A of the pawl gear 7 into which it was engaged, and abuts the inclined plane on the winding direction W side of the pawl teeth 7A positioned on the unwinding direction P side.

[0113] Because the roller unit 4 then, as shown in Fig. 18, further rotates in the winding direction W, the engaging claw 9A of the pawl 9 is guided while abutting the inclined plane on the winding direction W side of the pawl teeth A and is forcibly rotated in the disengaging direction (arrow Y). Along with the rotation of the pawl 9 in the disengaging direction, the clutch 50 begins to resist the biasing force of the unwinding direction P due to the return spring 19 and rotate in the winding direction W of the webbing 2.

[0114] By rotating the clutch 50 in the winding direction W, the direction of the spring force F1 due to the return spring 19, ie the direction of the straight line connecting the fixing pin 59 of the clutch 50 and the fixing pin 18E of the return plate 18, changes, in contrast to the time of blocking, as shown by Fig. 18 to Fig. 20, gradually opposite the center line C1 of rotating the clutch 50 from the right side to the left side.

[0115] That is, the torque M1 acting on the clutch 50 due to the return spring 19 gradually changes from the unwinding direction P to the winding direction W of the belt webbing 2 of the clutch 50. Furthermore, Fig. 19 shows the state in which the fixing pin 59 of the clutch 50, the fixing pin 18E of the return plate 18, and the rotation center of the clutch 50 (point on the center line C1) are adjacent to each other on a straight line. Consequently, the state in which the spring force F1 acts in the direction toward the rotation center of the clutch 50 and no torque M1 is generated is shown.

[0116] Then, as in Fig. 20, the roller unit 4 continues to rotate in the winding direction W, the direction of the torque M1 pivots from the unwinding direction P to the winding direction W, wherein the torque M1 becomes larger as a result of the rotation of the roller unit 4 (clutch 50) in the winding direction W.

[0117] By switching the torque acting on the clutch 50 due to the return spring 19 around the center line C1 to the winding direction W, the direction of the preload force acting on the clutch 50 becomes the winding direction W, wherein, when the preload force in the winding direction W reaches a certain magnitude, the clutch 50 rapidly rotates in the winding direction W due to the preload force in the winding direction W, and the guide pin 9B of the pawl 9 is guided into the guide groove 56 due to the rotation of the clutch 50, is rapidly rotated in the disengaging direction and returns to the unblocked position. That is, the pawl 9 returns, as shown in Fig. 21, due to the biasing force of the return spring 19 in the winding direction W, the clutch 50 returns to the unblocked position and is held there. From this point on, free unwinding and winding of the webbing 2 is possible.

[0118] That is, since the clutch 50 is biased in the unwinding direction P by the return spring 19 in the locked state, whereas in a conventional belt retractor the clutch is biased in the winding direction W in the locked state, the connection of the clutch 50 to the lock 30 can be released by a small amount of wound up webbing after the lock is released. Therefore, when the lock is released, it is not necessary, as in a conventional belt retractor, to further generate relative rotation to the lock and the clutch after the clutch has returned the pawl to the disengaged position, and to rotate the reel in the winding direction of the webbing until the connection between the lock and the clutch is released, so that the lock can be quickly released with a small amount of wound up webbing.

[0119] As already mentioned, by means of the second arm part 19B of the return spring 19, a pretensioning force always acts on the guide groove 56 of the clutch 50 via the guide pin 9B of the pawl 9 by means of the torque M2 acting on the pawl 9 around the center line C2, rotating the clutch 50 in the winding direction W. Taking this into account, at the time when the torque M1 of Fig. 19 becomes zero, the direction of preload of the clutch 50 by the return spring 19 to the winding direction W. In other words, in the course of the change from the blocked state of Fig. 16 into the state where the torque M1 of Fig. 19 becomes zero, the direction of the preload force acting on the clutch 50 by the return spring 19 changes from the unwinding direction P to the winding direction W. As a result, when the blockage is released, the direction of the preload force acting on the clutch 50 by the return spring 19 can be changed to the winding direction W at the earliest possible stage, and the blockage can be released quickly.

[0120] In the lock release state, the locking pawl 9 is held at the unlocked position by the return spring 19 by applying a biasing force in the winding direction W to the fixing pin 18E of the return plate 18, and the clutch 50 is also held at the first position by applying a biasing force in the winding direction W to the fixing pin 59. As a result, the generation of noise due to rattling of the locking pawl 9 and the clutch 50, for example, due to vibrations of the vehicle, can be suppressed.

[0121] Furthermore, in the state of Fig. 20, the front end of the engaging claw 9A of the pawl 9 is positioned at the position of the diameter of the tooth crest height of the pawl teeth 7A, wherein the engaging claw 9A of the pawl 9 is guided by the pawl teeth 7A of the pawl gear 7 rotating in the winding direction W until this state is reached and is forcibly rotatable in the disengaging direction. That is, in the state of Fig. 20, the clutch 50 rotates to the position at which the torque M1 already acts in the winding direction W, so that when the blockage is released, the torque M1 can be safely switched to the winding direction W and the blockage can be released.

[0122] As explained above, in the webbing retractor of the present embodiment, in the locked state, that is, in the state where the locking pawl 9 is in the engaging position, the clutch 50 is biased in the unwinding direction P of the webbing 2 by the return spring 19. Furthermore, in a lock release state, that is, in the state where the locking pawl 9 is in the disengaging position, the clutch 50 is held at the first position by a biasing force in the winding direction W acting on the fixing pin 59 by the return spring 19. Here, the components, such as the return spring 19, which thus bias the clutch 50 in the unwinding direction and the winding direction of the webbing 2 in the locked state and the unblocked state, respectively, are generically referred to as clutch biasing components. (Second embodiment)

[0123] Next, a second embodiment of the present invention will be explained.

[0124] The first arm part 19A of the return spring 19 of the webbing retractor 200 according to the second embodiment is fixed to the coupling 50 (fixing pin 59) in the same manner as in the first embodiment, while the second arm part 19B is fixed to a fixing pin 22A provided on the first side wall 22 of the casing 3A.

[0125] In this respect, the first belt retractor 100 and the second belt retractor 200 differ from each other. Consequently, the return plate 18 used in the first embodiment is not used here. The remaining points, including the point that the pawl 9 is inserted into the mounting hole 29 of the first side wall 22 of the housing 3A and is rotatably attached to the first side wall 22 by means of the pawl rivet 20, are the same.

[0126] Fig. 22 to Fig. 24 are figures showing, in a sequence of operations of the belt retractor 200 from the unblocked state to the blocked state, the direction in which spring force F1 acts due to the return spring 19 and the direction of torque M1 acting on the clutch 50.

[0127] That means, Fig. 22 represents the normal state of the role, in other words, the unblocked state.

[0128] The first arm portion 19A of the return spring 19 is connected to the fixing pin 59 of the clutch 50, and the second arm portion 19B is connected to the fixing pin 22A of the first side wall 22 of the housing 3A. In the unlocked state, the clutch 50 is biased to rotate in the winding direction W (clockwise in the figure) via the first arm portion 19A. As a result, a biasing force acts on the pawl 9 via the guide groove 56 of the clutch 50 in the direction away from the pawl gear 7 (disengaging direction).

[0129] As in Fig. 22, in the clutch 50, the spring force F1 of the return spring 19 acting on the fixing pin 59 of the clutch 50 generates a torque M1 of the winding direction W around the center line C1, wherein the guide pin 9B of the pawl 9 is positioned at the lower edge of the guide groove 56 of the clutch shown in the figure and the pawl 9 rotates to the disengaging position, so that the clutch 50 is held at the first position.

[0130] Furthermore, the other end part 42 of the blocking arm 40 is held in the abutting state against the stopper 38 by the pretension of the sensor spring 45 (see Fig. 11).

[0131] Next, when the webbing 2 is suddenly unwound in an emergency situation of the vehicle and the acceleration of the unwinding direction P of the rotating roller 10 (acceleration of rotation) exceeds a certain value, as in connection with Fig. 11, around the arm support part 36 as the center under compression of the sensor spring 45 and the one end part 41 of the blocking arm 40 moves in the blocking triggering direction (direction of arrow L).

[0132] Next, when one end portion 41 of the locking arm 40 is engaged with the clutch gear 52, the clutch 50 is connected to the lock 30 through the locking arm 40 and rotates together with the lock 30 (reel 10 and pawl gear 7) in the webbing winding direction W while resisting the biasing force of the return spring 19 in the webbing winding direction P.

[0133] When the clutch 50 rotates in the unwinding direction P, the pawl 9 is rotated in the engaging direction. That is, the clutch 50 rotating in the unwinding direction P causes the pawl 9 to rotate from the disengaged position toward the engaging position.

[0134] Fig. 23 illustrates, in the process in which the pawl 9 rotates from the unblocked position to the blocked position by the clutch 50 rotating in the unwinding direction P, the state in which the fixing pin 22A provided on the first side wall 22 of the housing 3A, the fixing pin 59 of the clutch 50, and the rotation center of the clutch 50 (point on the center line C1) are adjacent to each other on a straight line, in other words, the state in which the spring force F1 acts in the direction directed to the rotation center of the clutch 50 and as shown in Fig. 14 no torque M1 is generated.

[0135] From the state of Fig. 23, as in the first embodiment, as the clutch 50 continues to rotate in the unwinding direction P and the pawl 9 rotates to the engaging position, the direction of the torque M1 acting on the clutch 50 by the return spring 19 changes from the winding direction W to the unwinding direction P.

[0136] As a result, in the blocked state, as in Fig. 24, the direction of action of the pretensioning force acting on the clutch 50 due to the return spring 19 is the webbing unwinding direction P, and in the blocked state, the clutch 50 is held at the second position by being pretensioned in the unwinding direction P by the return spring 19.

[0137] When the blocking is released by the blocking mechanism 8, as in the first embodiment, the tensile force of the unwinding direction applied to the webbing 2 is removed, the roller unit 4 (roller 10) and the lock 30 integrally fastened with the pawl gear 7 of the roller unit 4 rotate in the winding direction W by the biasing force of the coil spring 70 of the coil spring unit 5, so that the webbing 2 is wound up.

[0138] Then, as in the first embodiment, the clutch 50 is biased in the unwinding direction P by the return spring 19, and held at the second position in the state of guiding the pawl 9 to the engaging position so that it does not rotate in the winding direction W, and the lock 30 is rotated relative to the clutch 50 in the winding direction W. When the magnitude of the relative rotation angle reaches the magnitude of the relative rotation angle required to disengage the one end portion 41 of the lock arm 40 from the clutch gear 52, the one end portion 41 of the lock arm 40 rotates by the biasing force of the sensor spring 45 and moves away from the clutch gear 52, so that the connection of the clutch 50 with the lock 30 is released.

[0139] On the other hand, just as in the first embodiment, after the coupling 50 is released from the lock 30, the engaging claw 9A of the pawl 9 is guided into the pawl teeth 7A of the pawl gear 7 rotating in the winding direction W and is forcibly rotated in the disengaging direction. Along with the rotation of the pawl 9 in the disengaging direction, the clutch 50 resists the biasing force of the unwinding direction P due to the return spring 19 and rotates in the winding direction W of the webbing 2.

[0140] Due to the rotation of the clutch 50 in the winding direction W, the torque M1 acting on the clutch 50 due to the return spring 19 gradually changes around the center line C1, reverse to the time of the blocking operation, from the unwinding direction P to the winding direction W of the webbing 2 of the clutch 50. That is, as in Fig. 25, the spring force F1 of the return spring 19 acts in the direction toward the rotation center of the clutch 50, and after the torque M1 acting on the clutch 50 becomes zero, the direction of preload of the clutch 50 pivots from the unwinding direction P to the winding direction W.

[0141] From then on, when the preload force in the winding direction W reaches a certain size, the clutch 50 quickly rotates in the winding direction W due to the preload force in the winding direction W, the pawl 9 quickly returns to the disengaged position by guiding the guide pin 9B into the guide groove 56, the clutch 50 returns to the first position and is held there and returns to the Fig. 22, i.e., the unblocked state. From this point on, unwinding and rewinding of the belt 2 is possible. (Third embodiment)

[0142] Next, a third embodiment of the present invention will be explained.

[0143] In the webbing retractor 300 of the third embodiment, the first arm portion 19A of the return spring 19 is fixed to the fixing pin 22B provided on the first side wall 22 of the casing 3A, and the second arm portion 19B is fixed to the guide pin 9B of the locking pawl 9.

[0144] That is, while one end portion of the return spring 19 is fixed to the fixing pin 59 of the clutch 50 in the retractor 200 of the second embodiment, it is fixed to the fixing pin 22B provided on the first side wall 22 of the housing 3A in the retractor 300 of the third embodiment. Furthermore, while the return spring 19 was a coil spring in the retractor 200 of the second embodiment, it is a roughly V-shaped wire spring in the retractor 300 of the third embodiment. The two differ in this respect, while the other respects are the same.

[0145] Fig. 26 to Fig. 28 are diagrams showing, in the webbing retractor 300 of the third embodiment, the direction in which the spring force F2 due to the return spring 19 acts and the direction of the torque M2 due to the biasing force acting on the pawl 9 during the series of operations from the unblocked state to the blocked state.

[0146] That means, Fig. Figure 26 is a sectional view showing the normal state of the reel, in other words, the unblocked state.

[0147] In the return spring 19, the first arm part 19A is connected to the fastening pin 22B of the first side wall 22 of the housing 3A and the second arm part 19B is connected to the guide pin 9B of the pawl 9, wherein the guide pin 9B of the pawl 9 is pretensioned in the unblocked state via the second arm part 19B to rotate in the disengaging direction.

[0148] As in Fig. As shown in Figure 26, the spring force F2 of the return spring 19 acting on the guide pin 9B of the locking pawl 9 imparts the torque M2 of the disengaging direction to the locking pawl 9 around the center line C2, so that the locking pawl 9 is biased to rotate in the disengaging direction. Consequently, the clutch 50 is biased to rotate in the winding direction W via the guide pin 9B of the locking pawl 9. As a result, the guide pin 9B of the locking pawl 9 is positioned at the lower edge of the guide groove 56 of the clutch, the locking pawl 9 rotates to the disengaging position, and the clutch 50 is held at the first position.

[0149] Furthermore, in this case too, the other end part 42 of the blocking arm 40 is held in the state abutting against the stopper 38 by the pretension of the sensor spring 45 (see Fig. 11).

[0150] Next, when the webbing 2 is suddenly unwound in an emergency situation of the vehicle and the acceleration of the unwinding direction P of the rotating roller 10 (acceleration of rotation) exceeds a certain value, as in connection with Fig. 11, the arm support part 36 is used as the center under compression of the sensor spring 45, and one end part 41 of the blocking arm 40 moves in the direction of blocking release (direction of arrow L).

[0151] Next, when one end portion 41 of the blocking arm 40 is engaged with the lock 30, the clutch 50 is connected to the lock 30 through the blocking arm 40 and rotates together with the lock 30 (roller 10 and pawl gear 7) in the unwinding direction P while resisting the biasing force of the return spring 19 in the winding direction W.

[0152] When the clutch 50 rotates, the pawl 9 is rotated in the engaging direction, resisting the biasing force of the return spring 19 in the winding direction W. That is, the rotating clutch 50 rotates the pawl 9 from the disengaging position toward the engaging position.

[0153] Fig. 27 shows the state in which the fixing pin 22B of the first side wall 22 of the casing 3A, the guide pin 9B of the pawl 9, and the rotation center of the pawl 9 (point on the center line C2) are adjacent to each other on a straight line, in other words, the state in which the spring force F2 acts in the direction toward the rotation center of the pawl 9 and no torque M2 is generated.

[0154] From the state of Fig. 27, as the clutch 50 continues to rotate and the pawl 9 moves toward the engaging position, the direction of the torque M2 acting on the pawl 9 by the return spring 19 changes from the disengaging direction to the engaging direction. Accompanying this, the direction of the preload force acting from the return spring 19 via the guide pin 9B of the pawl 9 onto the guide groove 56 of the clutch 50 also changes from the winding direction W to the unwinding direction P of the clutch 50.

[0155] In other words, as in the first and second embodiments, in the process in which the clutch 50 starts to rotate and the pawl 9 rotates to the engaging position, the biasing force acting on the clutch 50 due to the return spring 19 changes from the winding direction W to the unwinding direction P.

[0156] As a result, in the blocked state, as in Fig. 28, the direction of action of the preload force acting on the clutch 50 due to the return spring 19 is the unwinding direction P, and in the locked state, the clutch 50 is held at the second position by being preloaded in the unwinding direction P by the return spring 19.

[0157] When the blocking of the roller 10 by the blocking mechanism 8 is released, as in the first and second embodiments, the tensile force of the unwinding direction applied to the webbing 2 is removed, the roller unit 4 (roller 10) and the lock 30 integrally fastened with the pawl gear 7 of the roller unit 4 rotate in the winding direction W by the biasing force of the coil spring 70 of the coil spring unit 5, so that the webbing 2 is wound up.

[0158] Further, as in the first and second embodiments, the clutch 50 is biased in the unwinding direction P by the return spring 19 and held at the second position so as not to rotate in the winding direction W, and the lock 30 rotates relative to the clutch 50 in the winding direction W. When the magnitude of the relative rotation angle reaches the magnitude of the relative rotation angle required to disengage the one end portion 41 of the lock arm 40 from the clutch gear 52, the one end portion 41 of the lock arm 40 rotates by the biasing force of the sensor spring 45 and moves away from the clutch gear 52, so that the connection of the clutch 50 with the lock 30 is released.

[0159] On the other hand, as in the first and second embodiments, after the clutch 50 is released from the lock 30, the engaging claw 9A of the pawl 9 is guided into the pawl teeth 7A of the pawl gear 7 rotating in the winding direction W, and is forcibly rotated in the disengaging direction against the biasing force of the engagement direction by the return spring 19. Together with this, the clutch 50 rotates in the winding direction W.

[0160] By rotating the pawl 9 in the disengaging direction, the torque M2 changes around the center line C2 due to the return spring 19, reverse to the moment of blocking, from the engaging direction to the disengaging direction of the pawl 9. That is, as in Fig. As shown in Figure 29, the spring force F2 of the return spring 19 acts in the direction toward the rotation center of the pawl 9, and after the torque M2 acting on the pawl 9 becomes zero, the preload direction of the pawl 9 pivots from the engaging direction to the disengaging direction. Accompanied by this, the preload force acting on the guide groove 56 of the clutch 50 also pivots from the unwinding direction P to the winding direction W via the guide pin 9B of the pawl 9.

[0161] Then, when the preload force in the winding direction W reaches a certain size, the pawl 9 quickly rotates in the disengaging direction due to the preload force in the disengaging direction, returns to the disengaging position and is held there, and together with the rotation of the pawl 9, the clutch 50 quickly rotates in the winding direction W, returns to the first position and there is a return to the Fig. 26, the reel returns to its normal state, i.e., the unblocked state. From this point on, unwinding and rewinding of the belt 2 is possible.

[0162] As explained above, in the third embodiment, the pawl is biased to rotate in the engagement direction when the pawl is in the engaging position, and is biased to rotate in the disengaging direction when the pawl is in the disengaging position. These rotation biasing components are generically referred to herein as pawl biasing components. In other words, in the third embodiment, the return spring 19 is both a clutch biasing component and a pawl biasing component.

[0163] Since, as in the first embodiment, in the second and third embodiments described above, the clutch 50 is biased in the unwinding direction P by the return spring 19 in the blocked state, whereas in a conventional belt retractor the clutch is biased in the winding direction W in the blocked state, the connection of the clutch 50 to the lock 30 can be released by means of a small wound-up amount of belt webbing after the start of the release of the blocking.As a result, when releasing the lock, it is not necessary, as in a conventional belt retractor, after the clutch has returned the pawl to the disengaged position, to further generate relative rotation to the lock and the clutch and rotate the reel in the winding direction of the webbing until the connection of the lock to the clutch is released, so that the lock can be quickly released with a small amount of webbing wound up.

[0164] Regarding the locking operation in the first to third embodiments, the case where acceleration of the rotation of the reel 10 in the unwinding direction due to the sudden unwinding of the webbing 2 is detected was explained above, and by engaging one end portion 41 of the locking arm 40 with the clutch gear 52 of the clutch 50, the clutch 50 is connected to the lock 30 and the locking mechanism 8 is triggered. Next, an explanation will also be given for the case where, in an emergency situation of the vehicle, the acceleration of the vehicle is detected by the acceleration sensor 15 and the locking mechanism 8 is triggered.

[0165] That is, in an emergency situation of the vehicle (e.g. a collision or emergency braking), in the event that the acceleration of the vehicle has exceeded a certain acceleration, if it is the first embodiment, from the non-locked state of Fig. 12, the inertia body 15B of the acceleration sensor 15 moves due to the inertial force on the sensor holder 15A and pushes the sensor lever 15C upward. In other words, the acceleration sensor 15 detects the acceleration of the vehicle through the movement of the inertia body 15B and moves the locking claw 15D of the sensor lever 15C upward.

[0166] When the blocking claw 15D moves upward, the engaging pawl 60 of the clutch 50 is pushed upward by the ascending blocking claw 15D and engages with the teeth 34 of the ratchet wheel 35. Fig. 30 illustrates a modified example of the first embodiment showing this state. That is, the engaging pawl 60 of the clutch 50 engages the teeth 34 of the ratchet gear 35, thereby connecting the clutch 50 and the lock 30. In other words, in this case, the connecting mechanism that performs the connection and disconnection of the clutch 50 and the lock 30 includes the engaging pawl 60 of the clutch.

[0167] When the webbing 2 is subsequently unwound, in the state in which the engaging pawl 60 engages with the teeth 34, the clutch 50 rotates in the unwinding direction P, resisting the biasing force of the winding direction W of the return spring 19, together with the lock 30 and the roller 10.

[0168] When the clutch 50 rotates in the winding direction P, the guide pin 9B of the pawl 9 is guided by the guide groove 56 of the clutch 50, and the pawl 9 is moved to the engagement position engaging the pawl gear 7. That is, by the rotating clutch 50, the pawl 9 moves from the disengaging position toward the engaging position, and the engaging claw 9A of the pawl 9 engages the pawl teeth 7A. Fig. 31 represents this blocked state.

[0169] Incidentally, while the clutch 50 rotates in the winding direction P, the state of the engaging pawl 60 engaging with the teeth 34 of the ratchet wheel 35 is maintained, and further, as already mentioned, the direction of the biasing force acting on the clutch 50 by the return spring 19 changes from the winding direction W to the unwinding direction P. That is, in the blocked state of Fig. 32, the clutch 50 is preloaded by the return spring 19 in the unwinding direction P and held in the second position.

[0170] The above-explained locking operation of the locking mechanism 8 due to the acceleration sensor 15 detecting the acceleration of the vehicle in an emergency situation of the vehicle is carried out in the same way in the modified examples of the second and third embodiments.

[0171] Therefore, the explanation regarding the modified example of the first embodiment also applies to the modified examples of the second and third embodiments.

[0172] The release of the blocking state due to the connection of the pawl 9 with the pawl gear 7 occurs in the same sequence that was already carried out for the first to third embodiments in the event that the blocking mechanism 8 is triggered by a sudden unwinding of the belt webbing 2.

[0173] That is, in Fig. 32, when the webbing unwinding lock is released, even if the lock 30 rotates in the winding direction W due to the biasing force of the coil spring 70 of the coil spring unit 5, the clutch 50 is biased in the unwinding direction P by the return spring 19 and held at the second position so that it does not rotate in the winding direction W while the lock 30 rotates in the winding direction relative to the clutch 50. When the relative rotation angle reaches the relative rotation angle required to disengage the engaging pawl 60 of the clutch 50 from the teeth 34 of the ratchet wheel 35, the engaging pawl 60 of the clutch 50 rotates downward in the figure under its own weight and moves away from the clutch gear 52, thereby releasing the connection of the clutch 50 to the lock 30.From this point on, the release of the blocking mechanism occurs in the same sequence as in the first to third embodiments, in the event that the blocking mechanism 8 is triggered by a sudden unwinding of the belt webbing 2. This means, for example, that in the first embodiment, the release of the blocking mechanism occurs from this point on as follows. Fig. 19 to Fig. 21 shown.

[0174] Consequently, the explanation regarding the first to third embodiments is cited here.

[0175] Also in the case explained above that in an emergency situation of the vehicle the acceleration of the vehicle is detected by the acceleration sensor 15 and the blocking mechanism 8 is triggered, as well as in the case that the acceleration of the rotation of the roller 10 in the unwinding direction due to a sudden unwinding of the webbing 2 is detected and the blocking mechanism 8 is triggered, the clutch 50 is pretensioned in the unwinding direction P by the return spring 19 in the blocked state, so that compared to the conventional belt retractor in which the clutch is pretensioned in the winding direction W in the blocked state, the release of the connection of the clutch 50 with the lock 30 can be carried out after the start of the release of the blocking with a small amount of webbing wound up.As a result, when releasing the lock, it is not necessary, as in a conventional belt retractor, after the clutch has returned the pawl to the disengaged position, to further generate relative rotation to the lock and the clutch and rotate the reel in the winding direction of the webbing until the connection of the lock to the clutch is released, so that the lock can be quickly released with a small amount of webbing wound up. [Reference symbol]

[0176] 100, 200, 300 ... belt retractor, 2 ... webbing, 3 ... housing unit, 3A ... housing, 4 ... roller unit, 5 ... clock spring unit, 6 ... blocking unit, 7 ... pawl gear, 7A ... pawl teeth, 7B ... pawl base, 8 ... blocking mechanism, 9 ... pawl, 10 ... roller, 11 ... first end part, 12 ... second end part, 13 ... winding part, 14 ... torsion bar, 15 ... acceleration sensor, 16 ... shaft hole, 17 ... shaft, 18 ... recoil plate, 19 ... recoil spring, 21 ... back wall, 22 ... first side wall, 23 ... second side wall, 24 ... fixing plate, 25 ... first opening, 25A ... pawl housing, 26 ... second opening, 30 ... Lock, 35 ... ratchet wheel, 36 ... arm support part, 37 ... support pin, 38 ... stopper, 39 ... sensor cover, 40 ... blocking arm, 41 ... one end part, 45 ... sensor spring, 46 ... guard, 48 ... mechanism cover, 48A ... first housing part, 48B ... second housing part, 48C ... bearing boss, 48D ... hole, 50 ...Clutch, 51 ... inner wall, 52 ... clutch gear, 53 ... outer wall, 54 ... central opening, 55 ... guide part, 56 ... guide groove, 57 ... engagement pawl support part, 58 ... stopper, 60 ... engagement pawl, 61 ... fixing part, 62 ... engagement claw, 70 ... coil spring, 71 ... spring housing, 72 ... spring leaf, 73 ... spring shaft, 74 ... fixing part, 75 ... recess, 76 ... bearing hole, 77 ... pin, W ... winding direction, P ... unwinding direction.

Claims

[1] Belt retractor (100, 200, 300) for a safety belt, which a housing (3A) with a pair of opposite side walls (22, 23), a roller (10) rotatably housed between the pair of side walls (22, 23), to which one end of a webbing (2) is fixed, and which rotates in a webbing winding direction biased by a winding biasing component (5) for rotation, and is rotatable in the webbing unwinding direction by unwinding the webbing (2), and a blocking mechanism (8) which, in an emergency situation, prevents rotation of the roller (10) in the unwinding direction in response to an acceleration of the vehicle or an acceleration of the unwinding of the belt webbing (2), wherein the blocking mechanism (8) a ratchet gear (7) provided at one end (11) of the roller (10) and rotating integrally with the roller (10), a pawl (9) which is rotatably held on a side wall of the side wall pair (22, 23) and is displaceable between an engaging position, at which it engages the teeth of the pawl gear (7) by turning in the engaging direction and can thus prevent rotation of the roller (10) in the unwinding direction, and a disengaging position, at which engagement with the pawl gear (7) is released by turning in the disengaging direction and thus rotation of the roller (10) in the unwinding direction is permitted, a lock (30) which is non-rotatable relative to the ratchet gear (7) and is also coaxially mounted so that it rotates integrally with the roller (10), a coupling (50) which is coaxial with the roller (10) and is also arranged to be relatively rotatable, and in an emergency situation of the vehicle, moves the pawl (9) into the engaging position by rotating integrally with the lock (30) rotating in the unwinding direction, and a connection mechanism (15, 40, 45, 60) which detects an emergency situation of the vehicle, to form the coupling (50) with the locking device (30) in one piece and rotatably connected, whereby the clutch (50) rotates in the unwinding direction due to the roller (10) rotating in the unwinding direction when the clutch (50) is connected to the lock (30), so that the locking pawl (9) is moved into the engaging position and thus rotation of the roller (10) in the unwinding direction is prevented, and in that from the state in which the pawl (9) prevents rotation of the roll (10) in the unwinding direction, the roll (10) is rotated in the winding direction, on the one hand the clutch (50) is rotated in the winding direction, and on the other hand the pawl (9) returns to the disengaging position, characterized by , that the blocking mechanism (8) further a clutch preloading component (19), which, in the state in which the pawl (9) is in the disengaging position, biases the clutch (50) to rotate in the winding direction, and in the state in which the pawl (9) is in the engaging position, biases the clutch (50) to rotate in the unwinding direction, wherein after connecting the clutch (50) to the lock (30) by rotating the roller (10) in the unwinding direction, the direction of the bias to rotate the clutch (50) changes in the unwinding direction due to the clutch biasing component (19), the connection of the clutch (50) to the lock (30) due to the connecting mechanism (15, 40, 45, 60) in the state in which the clutch biasing component (19) biases the clutch (50) to rotate in the unwinding direction is thereby released, that the pawl gear (7) is moved relative to the clutch (50) in the winding direction, and after the release of the connection of the clutch (50) to the lock (30) by the roller (10) rotating in the winding direction, the direction of the pretension of the rotation of the clutch (50) is changed to the winding direction due to the clutch pretensioning component (19). [2] Belt retractor (100, 200) for a safety belt according to claim 1, characterized by , that in the belt retractor (100, 200) for a safety belt the clutch (50) is in a first position when the pawl (9) is in the disengaged position, and is in a second position when the pawl (9) is in the engaged position, the clutch (50) is in the area of ​​the first position and the second position coupled with the pawl (9), the connection of the clutch (50) to the lock (30) is released by means of the connecting mechanism (15, 40, 45, 60), in that in the state in which the clutch (50) is in the second position, by rotating the roller (10) in the winding direction, the pawl gear (7) rotates relative to the clutch (50) in the unwinding direction, and in that the roller (10) continues to rotate in the winding direction, the pawl gear (7) rotating in the winding direction rotates the clutch (50) via the pawl (9) in the winding direction, so that the direction of the rotational preload of the clutch (50) is changed from the unwinding direction to the winding direction due to the clutch preloading component (19). [3] Belt retractor (100) for a safety belt according to claim 1 or 2, characterized byin that in the belt retractor (100) for a safety belt, one end (19A) of the clutch pretensioning component (19) is fastened to the clutch (50) and the other end (19B) is fastened to the pawl (9). [4] Belt retractor (100) for a safety belt according to claim 3, characterized by , that in the belt retractor (100) for a safety belt, the pretensioning direction for rotating the clutch (50) is changed from the winding direction to the unwinding direction by rotating the clutch (50) due to the one end (19A) of the clutch pretensioning component (19), and the other end (19B) of the clutch biasing component (19) always biases the pawl (9) towards the disengaging position, so that the clutch (50) is biased to rotate in the winding direction, and at least in the state in which the pawl (9) is in the engaging position, the biasing force for rotating in the unwinding direction of the clutch (50) due to one end (19A) of the clutch biasing component (19) acting on the clutch (50) is greater than the biasing force for rotating in the winding direction of the clutch (50) due to the other end (19B) of the clutch biasing component (19). [5] Belt retractor (200) for a safety belt according to claim 1 or 2, characterized by in that in the belt retractor (200) for a safety belt, with respect to the clutch pretensioning component (19), one end (19A) is fastened to the clutch (50) and the other end (19B) is fastened to one side wall of the housing (3A). [6] Belt retractor (300) for a safety belt according to claim 2, characterized by , that in the belt retractor (300) for a safety belt, with respect to the clutch pre-tensioning component (19), one end (19B) is fastened to the pawl (9) and the other end (19A) is fastened to the housing (3A), wherein the clutch pre-tensioning component (19) pre-tensions the rotation of the clutch (50) via the pawl (9). [7] Belt retractor (300) for a safety belt, which a housing (3A) with a pair of opposite side walls (22, 23), a roller (10) rotatably housed between the pair of side walls (22, 23), to which one end of a webbing (2) is fixed and which is biased to rotate by a winding biasing component (5) so that it rotates in a webbing winding direction, and is rotatable in the webbing unwinding direction by unwinding the webbing (2), and a blocking mechanism (8) which, in an emergency situation, prevents rotation of the roller (10) in the unwinding direction in response to an acceleration of the vehicle or an acceleration of the unwinding of the belt webbing (2), wherein the blocking mechanism (8) a ratchet gear (7) provided at one end (11) of the roller (10) and rotating integrally with the roller (10), a pawl (9) which is rotatably held on a side wall of the side wall pair (22, 23) and is displaceable between an engaging position, at which it engages the teeth of the pawl gear (7) by turning in the engaging direction and can thus prevent rotation of the roller (10) in the unwinding direction, and a disengaging position, at which engagement with the pawl gear (7) is released by turning in the disengaging direction and thus rotation of the roller (10) in the unwinding direction is permitted, a lock (30) which is non-rotatable relative to the ratchet gear (7) and is also coaxially mounted so that it rotates integrally with the roller (10), a coupling (50) which is coaxial with the roller (10) and is also arranged to be relatively rotatable, and in an emergency situation of the vehicle, moves the pawl (9) into the engaging position by rotating integrally with the lock (30) rotating in the unwinding direction, and a connecting mechanism (15, 40, 45, 60), which detects an emergency situation of the vehicle in order to connect the coupling (50) to the lock (30) in one piece and rotatably, wherein in that the roller (10) rotates in the unwinding direction when the clutch (50) is connected to the lock (30), the clutch (50) rotates in the unwinding direction so that the locking pawl (9) is moved into the engaging position and thus rotation of the roller (10) in the unwinding direction is prevented, and in that from the state in which the pawl (9) prevents rotation of the roll (10) in the unwinding direction, the roll (10) is rotated in the winding direction, on the one hand the clutch (50) is rotated in the winding direction, and on the other hand the pawl (9) returns to the disengaging position, characterized by , that the blocking mechanism (8) further a pawl biasing component (19) which biases the pawl (9) to rotate in the disengaging direction when the pawl (9) is in the disengaging position, and biases the pawl (9) to rotate in the disengaging direction when the pawl (9) is in the engaging position, pre-tensions the pawl (9) to rotate in the engaging direction, whereby after connecting the clutch (50) to the lock (30), by rotating the roller (10) in the unwinding direction, the direction of the rotational preload of the pawl (9) changes to the engaging direction due to the pawl preloading component (19), the connection of the clutch (50) to the lock (30) due to the connecting mechanism (15, 40, 45, 60) in the state in which the pawl prestressing component (19) prestresses the pawl (9) in the engaging direction is released by rotating the pawl gear (7) relative to the clutch (50) in the winding direction, and after the release of the connection of the clutch (50) with the lock (30) by the roller (10) rotating in the winding direction, the direction of the rotational preload of the pawl (9) is changed to the disengaging direction due to the pawl preloading component (19).

Images