SEAT BELT GUIDE RING

Abstract: An improved guide ring assembly consists of a guide member (32) which is adapted to be pivotally mounted to a portion of an automotive vehicle and a plastics cover member (48) which is snap fit over the guide member (32). The guide member and cover member cooperate to define first and second anti-twist elements (42,56) for preventing twisting or roping of a seat belt (20,22) as it is drawn from its vehicle occupant restraining position to the retractor from which it has been paid out.

Description: The present invention relates generally to guide rings for automotive safety belt systems and more particularly to improvements in the anti-twist features for such guide rings. To enhance the convenient use of automotive seat belts, it is highly desirable to prevent the twisting or roping of the belt upon its retraction into the seat-belt retractor after use. A twisted belt does not readily retract fully and may make its subsequent deployment in the occupant restraining position difficult and time consuming. In seat belt systems for restraining front seat occupants in automobiles, a guide ring, commonly referred to as a "D" ring, is normally positioned at or near the roof or supporting pillar positioned just rearward of the occupants. The seat belt is fed through this ring from the retractor to the seat belt's tongue or other locking element. This guide ring is used both to properly position the shoulder belt across the front seat occupant and to guide the passage of the belt during deployment and retraction. Great attention has been given to the design of the slot in the guide ring in an attempt to prevent the twisting of the belt during restraining use. An example of such slot designs is that shown in U.S. 4,023,826, in which a slot is profiled to resist the tendency of the belt to twist and jam under certain side loads. Another approach to providing an anti-twist feature is that shown in U.S. 4,142,274 in which a simple slot is overlaid with a portion of the guide ring. While approaches such as the foregoing have been effective in many cases in which the belt is partially side loaded in use, the desire to improve the inhibition of twisting during unloaded seat belt retraction after use is a continuing design goal. According to the present invention, there is provided a guide ring assembly for controlling the movement of an automobile seat belt from its occupant restraining position to its stored position in a seat belt retractor, the guide ring assembly comprising, a body member including a mounting portion for pivotally mounting the body member on an interior portion of the automobile and a guide portion having a first slot formed therethrough substantially alignable with the path of the seat belt to the retractor, the first slot being closely sized to the thickness of the seat belt, characterised by a cover member carried on the body member in overlying fashion and having an edge portion positioned adjacent the exit of the slot. Preferably, the cover member is formed of plastics material and its edge portion which acts as a secondary anti-twist means extends laterally substantially over the width of the first slot. The invention will now be described further, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a view of a portion of an automotive front seat belt assembly illustrating a guide ring assembly installed on a vehicle support pillar, Figure 2 is a front view of the guide ring assembly, certain portions broken away for clarity, Figure 3 is a side view of the guide ring assembly of Figure 2, and Figure 4 is a cross-sectional view taken along lines IV-IV of Figure 2. A guide ring assembly 10 is illustrated as being mounted on an interior portion of a pillar 12 of an automobile, such as the central pillar usually referred to as the "B" pillar of the automobile between front and rear panes of glass 14, 16 respectively. When the seat belt system, the remainder of which is not shown, is functioning to restrain a front seat occupant, the seat belt 18 of the system has a portion 20 extending forwardly to restrain the occupant and a portion 22 extending adjacent the pillar 12 to a floor mounted retractor assembly, shown schematically at 11, from which it has been paid out, usually through agency of a spring loaded spool. After release of the front portion 20 from the occupant, the retractor assembly 11 serves to wind up the belt 18 and the guide ring assembly 10 assumes a more nearly vertical position as is illustrated in Figure 2. Because of the flexibility of the belt 18, it is during this operation that the twisting or roping of the belt 18 may occur. The efficacy of the guide ring assembly 10 to prevent this twisting or roping can be best appreciated by reference to Figures 2 to 4. The guide ring assembly 10 comprises a body 24 and a cover member 26. The body 24 includes a mounting portion 28 through which is formed an aperture 30 for receiving a fastener, not shown, by which the guide ring assembly 10 may be fixed for pivotal movement to the pillar 12. Below the mounting portion 28 extends a guide portion 32 at an angle extending away from the face of the pillar 12 towards the interior of the automobile. A plurality of slots are formed through the guide portion 32 of the body 24. Uppermost as viewed in Figure 4 is a generally horizontally extending retaining slot 34 for receiving a catch portion 36 of the cover member 26. Next below, is a profile slot 38 which is formed as a substantially horizontal slot having enlarged end portions, as shown at 40 in Figure 2. The enlarged portions 40 guide and restrain the movement of the lateral edges of the belt 18 when it is in the restraining position, as shown in Figure 1, to resist twisting or roping of the belt 18 as its path changes from vertical as it leaves the retractor assembly 11 to diagonal as it crosses the front seat occupant of the automobile. The remaining lowermost slot 42 formed through guide portion 32 of the body 24 provides the primary means for inhibiting twisting of the belt 18 when the belt is doffed by the vehicle occupant. The cover member 26 is preferably formed as a moulded plastics part of cup-like configuration. It has a channel portion 44 formed to the interior of its upper surface including a wall portion 46 which engages a shoulder 47 formed at the upper end of the mounting portion 28 of the body 24. Spaced inwardly from the mounting portion 28, the wall 48 of the cover member defines with the mounting portion 28 a space 50 for enclosing the mounting fastener. At the lower terminus of the wall 48, a leg 52 terminating in the catch 36 extends perpendicularly for insertion into the retaining slot 34. When an automotive vehicle occupant releases his/her seat belt 18 from its occupant restraining position, the portion 22 adjacent the pillar 12 moves toward the retractor assembly 11, typically under the influence of a conventional spring-loaded spool mechanism. The portion 20 of the belt 18 extended towards the occupant passes through the slot 42 which is closely sized to the thickness of the belt 18, as may be seen in Figure 4, to resist the tendency to twist. The slot 42 is arranged to be alignable in the path of the seat belt 18 as it is drawn to the retractor assembly 11. Under the modest loads imposed by a typical seat belt retractor assembly 11, the smoothing action of the slot 42 is in most cases sufficient to prevent twisting. If, however, a portion of twisted belt exits, contact between the exit 54 of the slot 42 and the lower edge 56 of the cover member 26 will remove the twist from the belt since the edge 56 closely overlies the exit 54 of the slot 42 and lies in the path of the belt 18 as it is pulled toward the retractor assembly 11. The edge 56 is preferably sized to extend to a width greater than that of the seat belt 18 as may be seen in Figure 2.

Claims: A guide ring assembly for controlling the movement of an automobile seat belt (18) from its occupant restraining position to its stored position in a seat belt retractor (11), the guide ring assembly (10) comprising, a body member (24) including a mounting portion (28) for pivotally mounting the body member (24) on an interior portion of the automobile and a guide portion (32) having a first slot (42) formed therethrough substantially alignable with the path of the seat belt (18) to the retractor (11), the first slot (42) being closely sized to the thickness of the seat belt (18), characterised by a cover member (26) carried on the body member (24) in overlying fashion and having an edge portion (56) positioned adjacent the exit of the slot (42). A guide ring assembly as claimed in Claim 1, wherein the cover member (26) is formed of plastics material. A guide ring assembly as claimed in Claim 1 or 2, wherein the edge portion (56) extends laterally substantially over the width of the first slot (42). A guide ring assembly as claimed in any preceding claim, further comprising a tab portion integrally formed with a wall of the cover member (26) and extending towards the body member (24), and a second slot (34) formed through the body member guide portion (32) adjacent the first slot (42) for receiving the tab portion. A guide ring assembly as claimed in Claim 4, further comprising a catch portion (36) formed proximate the free end of the tab portion. A guide ring assembly as claimed in CLaim 4 or 5, wherein the body member (24) further includes a profiled slot (38) having enlarged end openings (40) formed through a portion of the body member (24) spaced from the first slot (42) in alignment with the path of the seat belt (18) distal the retractor (11).

Inventors: BOAG, JOHN
Applicants: FORD FRANCE S. A., FORD MOTOR COMPANY LIMITED, FORD-WERKE AKTIENGESELLSCHAFT
Application year: 1988
Main classification: B60R22
IPC codes: B60R22