Seat belt latch plate assembly with two-shot noise dissipating bumpers

A seat belt latch plate assembly includes a latch plate and a latch plate cover carried on the latch plate. That latch plate cover is made by means of a two-shot injection molding process and includes integral bumpers that are made from a soft, sound dissipating material and have an energy absorbing cross-sectional shape.

TECHNICAL FIELD

This document relates generally to the motor vehicle equipment field and, more particularly, to a new and improved seat belt latch plate assembly that reduces the noise that assembly would otherwise make when unlatched and resting between the side of a car seat and the B-pillar of the motor vehicle.

BACKGROUND

When the front passenger seat belt is not in use, the latch plate assembly connected to the seat belt webbing rests in a narrow area between the B-pillar trim and the side of the car seat with the latch plate parked on the exposed seat belt webbing toward the car seat. This parked location keeps the seat belt latch plate assembly in an accessible position so that the passenger may easily find and grasp it when donning the seat belt.

However, it should be appreciated that when the vehicle is traveling on a bumpy or uneven road surface with the seat belt latch plate assembly in this position, the mass of the seat belt latch plate assembly can induce significant side-to-side movement. This may cause a repetitive impact with the side of the car seat which in turn generates an unwanted noise or rattle that can annoy or dissatisfy a motor vehicle operator or other occupant.

This document relates to a new and improved seat belt latch plate assembly with integral bumpers that address and resolve this issue in an effective and efficient manner. The bumpers are an effective passive countermeasure that performs the desired function without requiring the operator to take any specific action.

Better noise reduction is ensured through the softness, thickness, number, position and shape of the bumpers which absorb and dissipate impact energy over a wide range of contact severities and angles that would otherwise result in noise generation. The integral molded-in-place bumpers have a purposeful appearance while the soft material may be color keyed to the base plastic of the latch plate cover thereby providing an overall perception of quality and design excellence.

Advantageously, the integral bumpers provide for long-term durability as they are attached to the seat belt latch plate assembly through a two-shot injection molding process. Accordingly, the bumpers will not peel or delaminate with use or age.

SUMMARY

In accordance with the purposes and benefits described herein, a new and improved seat belt latch plate assembly is provided. That seat belt latch plate assembly comprises a latch plate and a latch plate cover carried on the latch plate. The latch plate cover includes a first integral bumper made from a noise dissipating material.

The first integral bumper may have a C-shaped cross section. The first integral bumper may be hemi-ellipsoid in shape. The first integral bumper may include a first wall defining a first open channel. The first integral bumper may include a first lip and a second lip. The first wall may be tapered toward the first lip and the second lip.

The latch plate cover may be a two-shot, single piece plastic overmold on the latch plate. In one possible alternative embodiment, the latch plate cover may comprise a base section overmold on the latch plate and a two-shot, snap-on trim cover secured to the base section.

The seat belt latch plate assembly may further include a second integral bumper spaced from the first integral bumper. In such an embodiment, both of the first and second integral bumpers may be hemi-ellipsoid in shape.

The first integral bumper may include a first wall defining a first open channel. The second integral bumper may include a second wall defining a second open channel. The first wall may include a first lip and a second lip. The second wall may include a third lip and a fourth lip. The first wall may be tapered toward the first lip and the second lip. The second wall may be tapered toward the third lip and the fourth lip.

The latch plate cover may comprise a two-shot, single-piece overmold on the latch plate. That two-shot, single-piece overmold may include (a) a body section molded from a first material and (b) first and second integral bumpers molded from a second material. The first material is more rigid than the second material and the second material is softer than the first material. The first material may be selected from a first group of materials consisting of nylon (polyamide), polypropylene and combinations thereof. The second material may be selected from a second group of materials consisting of thermoplastic elastomers.

In another possible embodiment, the latch plate cover comprises a two-shot snap-on trim cover and a cooperating base section overmold on the latch plate. The two-shot, snap-on trim cover may include (a) a body section molded from a first material and (b) first and second integral bumpers molded from a second material. The first material is more rigid than the second material and the second material is softer than the first material. The first material may be selected from a first group of materials consisting of nylon (polyamide), polypropylene and combinations thereof. The second material may be selected from a second group of materials consisting of thermoplastic elastomers.

In the following description, there are shown and described several preferred embodiments of the seat belt latch plate assembly. As it should be realized, the seat belt latch plate assembly is capable of other, different embodiments and its several details are capable of modification in various, obvious aspects all without departing from the seat belt latch plate assembly as set forth and described in the following claims. Accordingly, the drawings and descriptions should be regarded as illustrative in nature and not as restrictive.

Reference will now be made in detail to the present preferred embodiments of the seat belt latch plate assembly, examples of which are illustrated in the accompanying drawing figures.

DETAILED DESCRIPTION

Reference is now made toFIGS. 1-8illustrating the new and improved seat belt latch plate assembly10. The seat belt latch plate assembly10includes a latch plate12, made from steel, metal or other high strength material, and a latch plate cover14, carried on the latch plate.

The latch plate12includes a tongue body16having a latching lug18with a central opening20. As is known in the art, the latching lug18is received and secured in the latch member of a seat belt buckle (not shown). The tongue body16also includes a guide slot22that receives the seat belt webbing24upon which the latch plate assembly10is carried.

The latch plate cover14includes a first integral bumper26and a second integral bumper28spaced from the first integral bumper. The two bumpers26,28are made from a material that will dissipate noise when the seat belt latch plate assembly10engages, for example, the side of a car seat30as illustrated inFIGS. 2, 3 and 4. For purposes of this document, a noise dissipating material is defined as a thermoplastic elastomer.

In the embodiment illustrated inFIGS. 1-5, the latch plate cover14includes a body section32molded from a plastic material while the first and second integral bumpers26,28of the latch plate cover are molded from an elastomer material. The plastic material is more rigid than the elastomer material and the elastomer material is softer than the plastic material.

The bumpers26,28may assume a number of different shapes. As best illustrated inFIG. 1, each of the bumpers26,28may be hemi-ellipsoidal in shape. As illustrated best inFIGS. 5 and 6, the first integral bumper26includes a first wall34having a first lip36and a second lip38outlining a first open channel40defined by the first wall. Further, the first wall34tapers toward the first lip36and the second lip38. Similarly, as illustrated best inFIGS. 7 and 8, the second integral bumper28includes a second wall42having a third lip44and a fourth lip46outlining a second open channel48defined by the second wall. Further, the second wall42tapers toward the third lip44and the fourth lip46. As a result, the first and second integral bumpers26,28each have an energy-absorbing, substantially C-shaped cross section as best illustrated inFIGS. 5 and 7.

The hollow cross-section, tapered wall thickness (thicker at the base, thinner at the lips36,38) and curved shape of the bumpers26,28help to define the operating characteristics of the bumpers. Those bumpers26,28are initially highly compliant to dissipate energy from the impact of the latch plate assembly10against the car seat30. That compliance progressively decreases to slow the latch plate assembly10after initial contact (seeFIGS. 6 and 8) and prevent other parts thereof from contacting the car seat30.

The elastomer material from which the bumpers26,28are constructed is soft enough to maintain flexibility and durable enough to resist warping or degradation in a typical vehicle environment. The elastomer material is also compatible with the plastic material so as to enable two-shot injection molding of the latch plate cover14by two-shot molding processes generally known in the art. In at least some embodiments, the first and second integral bumpers26,28will also be color matched to the body section32.

The body section32of the latch plate cover14may be made from a plastic material selected from a first group of materials consisting of nylon (polyamide), polypropylene and combinations thereof. The first and second bumpers26,28may be made from an elastomer material selected from a second group of materials consisting of thermoplastic elastomers. Here it should be appreciated that the listed materials are merely exemplary of those that could be used and should not be considered as limiting in scope.

As should be appreciated, the size, quantity and external shape of the integral bumpers26,28on the latch plate cover14may be varied in order to provide the desired performance and the elimination of rattles and noise when the latch plate assembly10is unbuckled and resting between the side of the car seat30and the B-pillar of the motor vehicle. The height of the bumpers26,28should prevent contact of all parts of the latch plate12against the car seat30when resting unbuckled. The number and external shape of the bumpers26,28may best be determined by the shape of the surface of the car seat30where the latch plate assembly10makes contact and the dimensional stability of the bumper or second material.

As illustrated inFIG. 9, in one possible embodiment the latch plate cover14may comprise a two-shot, single-piece plastic overmold on the latch plate12.

As illustrated inFIG. 10, in an alternative embodiment, the latch plate cover14may comprise a two-shot, snap-on trim cover50and a cooperating base section overmold52on the latch plate12. The two-shot, snap-on cover50may be secured to the base section overmold52by any appropriate fastening means such as the cooperating pins54on the cover and the pin receivers56on the base section overmold.

The foregoing has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the embodiments to the precise form disclosed. Obvious modifications and variations are possible in light of the above teachings. For example, it should be appreciated that the latch plate cover14may assume other configurations. For example, one or more integral bumpers may also be provided on the opposite side or face of the latch plate cover14to prevent rattling against the side or pillar of the motor vehicle. All such modifications and variations are within the scope of the appended claims when interpreted in accordance with the breadth to which they are fairly, legally and equitably entitled.