Seatbelt assembly and seatbelt retractor with wedge clamp and force limiter

Abstract

Seat belt assembly (100) of a vehicle, comprising: a coil (115) connected to the body of the vehicle; a belt (105) at least partially wound around the spool (115); a wedge clamp (120) designed to selectively engage the belt (105); and a force-limiting plate (125) operatively connected to the coil (115), the force-limiting plate (125) having deformable teeth (140) configured to engage a pin (130), the teeth (140) being configured to deform through the pin (130) following a vehicle impact due to the force of the teeth (140) on the pin (130), and wherein the seat belt assembly (100) further comprises a seat belt retractor (110) in which the belt (105), spool (115) and wedge clamp (120) are arranged, and wherein the seat belt assembly (100) further comprises a retractor base plate (145) to which the wedge clamp (120) is frictionally connected via the seat belt retractor (110), and the force-limiting plate (125) is connected both to the retractor base plate (145) and to the body, characterized in that when the wedge clamp (120) engages the belt (105), a force transmitted from the retractor base plate (145) to the force-limiting plate (125) causes teeth (140) of the force-limiting plate (125) to press against the pin (130), which, when a set of the teeth (140) of the retractor base plate (145) and the force-limiting plate (125) are deformed, can allow it to slide in a direction guided by a channel (135) defined by the force-limiting plate (125) and in which the teeth (140) run and the pin (130) is arranged, until a next set of teeth (140) engages the pin (130).

Description

The invention relates to a seat belt retractor having a wedge clamp and a force limiting plate and to a seat belt assembly having the seat belt retractor.BACKGROUNDMost vehicles have a seat belt assembly that limits the movement of occupants in an accident. Sometimes, a pretensioner is used to prevent the seat belt from being locked before the accident occurs. However, when activated by itself, pretensioners do not prevent the seat belt from moving. For example, when a seat belt is wound on a reel, belt slack may accumulate. Simply activating the seatbelt pretensioner does not eliminate the seatbelt slack. The belt slack must be taken up during a collision before forward movement of the occupant can be stopped, referred to as "film spool effect".In document DE 695 16 490 T2 a seat belt arrangement is disclosed comprising a spool supported in a tensioner frame and locking upon rapid vehicle deceleration, and further comprising a belt at least partially wound around the spool and further comprising a force limiting plate connected to the spool, the force limiting plate comprising deformable teeth configured to engage a pin, the teeth configured to deform upon a vehicle impact.In the publication DE 92 02 219 U1, a locking device of a belt of a seat belt arrangement is disclosed, which is realized via a wedge clamp.It is the object to accommodate a seat belt during a collision of the vehicle independently of belt slacks.This object is achieved by a seat belt assembly according to claim 1 and a seat belt retractor according to claim 8.BRIEF DESCRIPTION OF THE DRAWINGSFIG. 1 illustrates an example seat belt system having a wedge clamp and a force limiting plate. FIG. 2 illustrates the seatbelt system of FIG. 1 after a vehicle impact.DETAILED DESCRIPTIONBy eliminating the film spool effect, the seat belt can more quickly engage with an occupant after a vehicle collision. An example seat belt system that eliminates or substantially reduces the film spool effect includes a spool, a harness, a wedge clamp, and a force limiting plate. The harness is at least partially wound around the spool. Before or immediately after the detection of a vehicle impact, the wedge clamp engages in the belt mechanism in a targeted manner. By activating the wedge clamp, the force exerted on the harness can act directly on the retractor base, i.e. without having to absorb a slack that may have accumulated otherwise than the harness has been wound around the spool. Consequently, the force applied to the retractor base is transmitted directly to the force limiting plate having deformable teeth engaging a pin. The force of the impact causes the pin to deform the teeth. Thus, the force-limiting plate absorbs a portion of the impact and reduces the force applied to the occupant during the impact.The elements shown may take many different forms and may include multiple and / or different components and devices. The example components shown are not intended to be limiting. Indeed, additional or alternative components and / or implementations may be utilized.As shown in FIG. 1, the seat belt system 100 includes a harness 105 and a retractor 110 having a spool 115, a wedge clamp 120, and a force limiting plate 125. The harness 105, sometimes referred to as a "webbing", may be made of a material such as nylon or polyester. At least a portion of the harness 105 may be wound around the spool 115. When the retractor 110 is not activated, the harness 105 may be unwound from the spool 115, for example, by pulling on the harness 105. When the retractor 110 is activated, the harness 105 may be locked relative to the spool 115 to, for example, maintain an occupant in his or her seat.The spool 115 may include a flanged cylinder configured to receive at least a portion of the harness 105. That is, a length of the harness 105 may be wound around the cylinder. In some cases, the spool 115 may be biased to keep the harness 105 wound around the cylinder. By pulling on the harness 105 with a sufficient force, the prestress can be overcome. The coil 115 is disposed on a vehicle body, for example, a vehicle seat, pillar, or other structure.The wedge clamp 120 may be configured to selectively engage the harness 105 to prevent the harness 105 from being unrolled or unrolled from the spool 115. However, when the wedge clamp 120 is not engaged, the harness 105 is free to be unrolled or rolled up relative to the spool 115. The wedge clamp 120 is disposed on the retractor base 145. When the wedge clamp 120 is engaged with the harness 105, any forces applied to the harness 105 can be transmitted from the clamp to the retractor base 145 and to the vehicle body without overcoming the bias of the spool 115. In other words, the wedge clamp 120 prevents the harness 105 from unwinding. Additionally, when the wedge clamp 120 is engaged, the force acting on the harness 105 can be applied directly to the retractor base 145 without having to absorb any slack that may have accumulated as the harness 105 has been wound around the spool 115. Consequently, the wedge clamp 120 substantially eliminates or reduces any film spool effect that may occur after a vehicle impact without a pretensioner. The actuation of the wedge clamp 120 may be electrically controlled, e.g., by a sensor signal. For example, the wedge clamp 120 may be engaged prior to a vehicle impact or immediately in response to a sensor detecting the vehicle impact.The force-limiting plate 125 is configured to absorb a portion of the vehicle impact. The force limiting plate 125 is attached to both the retractor base 145 and the vehicle body. The force limiting plate 125 includes deformable teeth 140 configured to engage a stud 130 projecting from the vehicle body. The teeth 140 extend from the force-limiting plate 125 into a channel 135 defined by the force-limiting plate 125, and the post 130 is disposed within the channel 135. When the wedge clamp 120 is closed and sufficient force is applied to the harness 105, the force transmitted from the retractor base 145 to the force limiting plate 125 may cause some teeth 140 to press against the post 130. The force of the teeth 140 on the post 130 causes some of the teeth 140 to be deformed, allowing the retractor base 145 and the force limiting plate 125 to slide in a direction guided by the channel 135 until the next set of teeth 140 engages the post 130. Assuming sufficient force remains, the pin 130 will deform one or more subsequent sets of teeth 140 with which it comes into contact. Upon each deformation of a set of teeth 140, the spool 115 and force-limiting plate 125 move relative to the vehicle body along the channel 135.FIG. 2 illustrates how the harness 105 and retractor 110 may look after a vehicle impact. As shown, the wedge clamp 120 is engaged and the teeth 140 of the force limiting plate 125 have been deformed by the pin 130. With the teeth 140 deformed, the retractor base 145 and the force limiting plate 125 were free to move along the channel 135, e.g., toward a front of the vehicle. Engagement of the wedge clamp 120 substantially eliminated or reduced the film spool effect, allowing the force limiting plate 125 to more quickly engage the post 130 after the vehicle impact. Otherwise, the teeth 140 of the force limiting plate 125 would not have engaged the pin 130 until all slack from the spool 115 had been removed.Simulated test results show that retractor 110, with wedge clamp 120 and force limiting plate 125 as described above, may reduce deflection of an occupant into a forward impact region, reduce occupant injury to the head, neck, and torso, and provide better kinematic occupant control during collisions. In addition, these test results can be achieved without incorporating a pretensioner into the seat belt system 100.

Claims

A seat belt assembly (100) of a vehicle, comprising: a spool (115) connected to the body of the vehicle; a belt (105) at least partially wound around the spool (115); a wedge clamp (120) configured to selectively engage the belt (105); and a force-limiting plate (125) operatively connected to the spool (115), the force-limiting plate (125) having deformable teeth (140) configured to engage a pin (130), the teeth (140) configured to deform through the pin (130) upon a vehicle impact by the force of the teeth (140) on the pin (130), and wherein the seat belt assembly (100) further comprises a seat belt retractor (110) in which the belt (105), A spool (115) and wedge clamp (120), and wherein the seat belt assembly (100) further comprises a retractor base plate (145) to which the wedge clamp (120) is frictionally connected via the seat belt retractor (110), and the force limiting plate (125) is connected to both the retractor base plate (145) and the body, characterised in that upon engagement of the wedge clamp (120) with the belt (105), a force transmitted from the retractor base plate (145) to the force limiting plate (125) causes teeth (140) of the force limiting plate (125) to press against the post (130), which may allow deformation of a set of the teeth (140) of the retractor base plate (145) and the force limiting plate (125) in one of a channel (135), which is defined by the force limiting plate (125) and in which the teeth (140) extend and the pin (130) is arranged to slide in a guided direction until a next set of teeth (140) engages the pin (130).The seat belt assembly (100) of claim 1, wherein the wedge clamp (120) is configured to engage the belt (105) to limit a film spool effect caused by the vehicle impact.The seat belt assembly (100) of any preceding claim, wherein the wedge clamp (120) is configured to engage the belt (105) prior to the vehicle impact.The seat belt assembly (100) of any preceding claim, wherein the wedge clamp (120) engages the belt (105) to reduce movement of the belt (105) relative to the spool (115).The seat belt assembly (100) of any preceding claim, wherein the spool (115) is disposed on a vehicle body.The seat belt assembly (100) of any preceding claim, wherein the belt (105) is configured to be wound onto or unwound from the spool (115) when the wedge clamp (120) is not engaged.The seat belt assembly (100) of any preceding claim, wherein the wedge clamp (120) is configured to reduce movement of the belt (105) relative to the spool (115) independent of a retractor.A seat belt retractor (110) of a vehicle, comprising: a spool (115) connected to the body of the vehicle and configured to receive a belt (105); a wedge clamp (120) configured to selectively engage the belt (105); and a force limiting plate (125) operatively connected to the spool (115), the force limiting plate (125) having deformable teeth (140) configured to engage a post (130), the teeth (130) configured to deform through the post (140) after a vehicle impact and after the wedge clamp (120) engages the belt (105) by the force of the teeth (130) on the post (130), and the seat belt retractor (110) further comprising a retractor base plate (145), and wherein the wedge clamp (120) is non-positively connected to the retractor base plate (145) via the seat belt retractor (110), characterized in that, when the wedge clamp (120) engages the belt (105), a force transmitted from the retractor base plate (145) to the force-limiting plate (125) causes teeth (140) of the force-limiting plate (125) to press against the pin (130), which, when a set of the teeth (140) of the retractor base plate (145) and the force-limiting plate (125) is deformed, can allow to slide in a direction guided by a channel (135) defined by the force-limiting plate (125) and in which the teeth (140) extend and the pin (130) is arranged until a next set of teeth (140) engages the pin (130).The seat belt retractor (110) of claim 8, wherein the wedge clamp (120) is configured to engage the belt (105) to limit a film spool effect.The seat belt retractor (110) of any of claims 8 or 9, wherein the wedge clamp (120) is configured to engage the belt (105) prior to the vehicle impact.The seat belt retractor (110) of any of claims 8 to 10, wherein the wedge clamp (120) engages the belt (105) to reduce movement of the belt (105) relative to the spool (115).The seat belt retractor (110) according to any one of claims 8 to 11, wherein the spool (115) is disposed on a vehicle body.The seat belt retractor (110) of any of claims 8 to 12, wherein engagement of the wedge clamp (120) prevents the belt (105) from being wound onto or unwound from the spool (115).The seat belt retractor (110) of any of claims 8 to 13, wherein the wedge clamp (120) is configured to reduce movement of the belt (105) relative to the spool (115) independent of a retractor.

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