Passive lap and shoulder belt system

The invention relates to a passive occupant restraining lap and shoulder belt system.

It is well known in motor vehicles to restrain an occupant in the seat by a lap belt disposed across the lap and a shoulder belt disposed diagonally across the chest. It is also known to connect the outboard belt ends to the door so that the belt is automatically moved between a restraining position about the occupant and a stowed position forwardly of the seat in response to movement of the door between open and closed positions. It is common in such passive belt systems to connect the outboard end of the lap belt to the door generally adjacent the hip of the occupant. However, it has been found that this low position of the belt obstructs occupant ingress and egress.

Accordingly, it has been recognized as desirable to move the outboard lap belt end forwardly and/or upwardly upon opening of the door to facilitate occupant ingress or egress. United States patent Keppel et al 3,680,883, issued August 1, 1972, and assigned to the assignee of this invention, provides a track on the door having a guide loop traveling therein to move the outboard lap belt end forwardly and upwardly upon opening of the door. Other prior art devices such as United States patents Westrate et al 3,815,934, issued June 11, 1974 and Keppel et al 3,770,078, issued November 6, 1973, and assigned to the assignee of this invention, provide a reel driven by a motor or a door responsive drive mechanism which winds a cord attached to the lap belt to pull the lap belt forwardly and upwardly upon opening movement of the door.

A passive occupant restraining belt arrangement according to the invention, for use in a vehicle body having an occupant compartment in which an occupant seat is accessible through a door opening selectively opened and closed by a movable door, comprises: a lap belt and a shoulder belt having inboard ends mounted on the vehicle body generally adjacent the hip of the occupant and outboard ends mounted on the door; and retractor means associated with the lap and shoulder belts for retracting the belts upon closing movement of the door and extending the belts upon opening movement of the door; in which arrangement the shoulder belt retractor means is provided on the door adjacent the hip of the occupant and mounts the outboard end of the shoulder belt; an anchor loop is mounted on the door generally adjacent the shoulder of the occupant and slidably receives the shoulder belt to dispose the shoulder belt diagonally across the chest of the occupant when the door is closed and dispose the shoulder belt in an occupant access position forwardly of the seat when the door is open; and a connecting means acts between the lap belt and the shoulder belt to move the lap belt along the door toward the anchor loop during opening movement of the door whereby the lap belt assumes an occupant access position generally parallel with the access position of the shoulder belt to facilitate occupant ingress and edgess.

The present invention provides a new and improved lap and shoulder belt systen wherein unwinding of the shoulder belt upon opening of the door lifts the lap belt to a stowed occupant access position generally parallel with the shoulder belt.

According to a preferred embodiment of the present invention a passive three-point lap and shoulder belt system has the inboard ends of the lap and shoulder belts mounted on the vehicle body generally adjacent the hip of the occupant by an emergency release buckle. Lap and shoulder belt retractors are mounted on the door generally adjacent the hip of the occupant for winding the belts thereon upon closing mouvement of the door and unwinding the belts therefrom upon opening movement of the door. An anchor loop is mounted on the door generally adjacent the shoulder of the occupant and slidably receives the shoulder belt to dispose the shoulder belt diagonally across the chest of the occupant when the door is closed and forwardly of the occupant when the door is open. A guide loop is attached to the shoulder belt at a point thereon which travels between the retractor and the anchor loop during movement of the door between open and closed positions. The guide loop slidably receives the lap belt to lift the lap belt from the retractor and vertically along the door toward the anchor loop during opening movement of the door so that the lap belt assumes a stowed occupant access position generally parallel with the shoulder belt to facilitate occupant ingress and egress. Closing of the door winds the shoulder belt and lowers the lap belt to the restraining position across the lap of the occupant.

The object, feature and advantage of the invention resides in the provision of a door mounted passive three-point lap and shoulder belt system wherein the unwinding of the shoulder belt from a retractor adjacent the hip of the occupant and toward a door mounted shoulder height anchor loop in response to opening movement of the door lifts the lap belt along the door from the lap of the occupant to a stowed occupant access position generally parallel with the shoulder belt.

This invention and how is may be performed are hereinafter particularly described with reference to the accompanying drawingj in which:-

• Figure 1 is a perspective view of a motor vehicle occupant compartment having a belt arrangement according to the invention, with the lap and shoulder belts shown in occupant restraining positions with respect to a phantom-line indicated seated occupant;
• Figure 2 is a sectional view taken in the direction of arrows 2-2 of Figure 1; and
• Figure 3 is a perspective view of the vehicle with the door shown in the open position moving the lap and shoulder belts to their stowed occupant access positions.

Referring to Figure 1, the vehicle body generally indicated at 10 defines a passenger compartment 12 in which an occupant seat 14 is provided for seating a phantom-line indicated occupant. The vehicle body has a door opening 16 which is selectively closed by a door 20 which has its forward end pivoted to the vehicle body.

As seen in Figure 1, the occupant is restrained in a seated position by a belt arrangement which includes a lap belt 24 and a shoulder belt 26. The inboard ends of lap belt 24 and shoulder belt 26 are joined at a latch plate 28. An emergency release buckle 30 mates with the latch plate 28 and is attached to the drive line tunnel 34 of the vehicle body by a short length of belt 36 and an anchor bolt 38.

As best seen in Figure 1, the outboard end of lap belt 24 is connected to the door 20 at a position generally adjacent the hip of the occupant to position the lap belt in an occupant restraining position When the door 20 is closed. The outboard end of the shoulder belt 26 is slidably mounted on the window frame 40 of the door 20 by an anchor loop 42 so that the shoulder belt 26 is disposed over the shoulder and across the chest of the occupant when the door 20 is closed.

Referring to Figure 2, it is seen that a retractor assembly generally indicated at 46 is attached to the door generally adjacent the hip of the occupant and includes a lap belt reel 48 to which the end of the lap belt 24 is attached and a shoulder belt reel 50 to which the end of shoulder belt 26 is attached. The reels 48 and 50 are respectively rotatable on reel shafts 52 and 54 and have associated winding springs, not shown, which rotate the reels in the counterclockwise direction as seen in Figure 2 to wind the lap and shoulder belts thereon. Ratchet teeth 58 and 60 are provided respectively on the reels 48 and 50 for engagement by a conventional latching mechanism, not shown, to lock the reels against belt unwinding rotation. The latching mechanism may be of the inertia actuated type such as United States patent Griffin 3,831,878, issued August 22, 1974 and incorporated herein by reference. The latching mechanism may also be connected to the door handle as in United States patent Keppel et al 3,770,078, issued November 6, 1973 or Arlauskas et al 3,692,328, issued September 19, 1972 and incorporated herein by reference. Other suitable prior art retractor locking mechanisms may also be used.

As best seen in Figure 2, the lap belt 24 is connected to the shoulder belt 26 by a guide loop 64 having a central aperture which slidably receives the lap belt 24 and which is attached to the shoulder belt 26 by a short length of strap 66 sewn to the shoulder belt. As seen by comparing Figures 1 and 3, the strap 66 attaches the guide loop 64 to the shoulder belt 26 at a point on the shoulder belt which travels vertically between the retractor assembly 46 and the anchor loop 42 during winding and unwinding of the shoulder belt 26 from the reel 50 in response to movement of the door 20 between the open and closed positions. Upon movement of the door 20 from the closed position of Figure 1 to the open position of Figure 3, the lap belt 24 is unwound from reel 48 and shoulder belt 26 is unwound from reel 50. During opening movement of the door, the guide loop 64 is lifted vertically along the door from adjacent the retractor assembly 46 to adjacent the anchor loop 42 so that the outboard portion of the lap belt 24 assumes a position generally parallel with the position of the shoulder belt 26 when the door reaches the full open position of Figure 3. During such vertical movement the lap belt 24 slides through the guide loop 64 to permit movement of the lap belt relative the shoulder belt and thereby accommodate an extent of lap belt unwinding which may differ from the extent of shoulder belt unwinding.

It will be understood that the position of the strap 66 connecting the guide loop 64 to the shoulder belt 26 determines how close the lap belt 24 approiches a parallel condition with the shoulder belt. It may be desirable to have the belts spaced somewhat from one another as seen in Figure 3 so that even though the door is fully open a still further unwinding of the lap and shoulder belts may be obtained as the occupant pushes the belts forwardly somewhat in order further to facilitate his entry or exit. Furthermore, the provision of the space between the lap and shoulder belts permits the occupant to reach between the belts to grasp the door handle to pull the door closed so that the shoulder belt will be positioned above the occupant's arm and the lap belt will be positioned below the occupant's arm. On the other hand, it may be desirable to have the belts more closely parallel when the door is open to provide an aesthetically pleasing system by minimizing the visual presence of the belt system.

As the door is pulled closed from its open position of Figure 3, the shoulder belt and lap belt are wound by their respective reels 48 and 50. The winding of shoulder belt 26 lowers the guide loop 64 along the door from adjacent the anchor loop 42 to adjacent the retractor assembly 46. Accordingly, the lap belt is lowered to the restraining position of Figure i across the lap of the occupant as the lap and shoulder belts are rewound.

Referring to Figures 1 and 2, it will be inderstood that the relative spacing of the retractor assembly 46 and anchor loop 42, the geometry of a particular seat belt system, or the movement of the seat or occupant rearward of the Figure 1 position may necessitate winding of the shoulder belt 26 beyond the position shown in Figure 2. Accordingly, the lower end 68 of the strap 66 may pass through an opening 70 of a plastic housing 72 on the retractor assembly 46 while the guide loop 64 rests upon the housing 72. The strap 66 attaching the guide loop to the shoulder belt will accordingly define a strap length sufficient to accommodate the maximum needed-extent of shoulder belt winding.

The aperture of anchor loop 42 is of adequate size to allow the upper end 74 of strap 66 to pass therethrough during shoulder belt unwinding upon door opening to lift the guide loop 64 into engagement with the guide loop 42 so that the lap belt 24 is parallel with the shoulder belt 26. It may be advantageous to employ a strap 66 of elastic material so that the shoulder belt 26 may be further unwound after guide loop 64 engages the anchor loop 42 by permitting the strap 66 to stretch and loop about the guide loop 64 after its upper end 74 and its lower end 68 have successively passed through the guide loop 42.

It will be understood that the lap belt reel 48 may be mounted inboard the seat in which case the outboard end of the lap belt may be fixedly attached to the door adjacent the shoulder belt reel. Furthermore, the inboard belt ends may be mounted on the seat.

Thus, it is seen that the invention provides a new and improved passive three-point lap and shoulder belt system wherein the shoulder belt lifts the lap belt vertically along the door to a stowed access position generally adjacent the shoulder belt upon opening movement of the door and lowers the lap belt onto the lap of occupant upon closing of the door.