AUTOMOTIVE DOOR CHECK WITH ENERGY STORAGE BODY FIELD OF THE INVENTION

This invention relates to automotive door check devices, and in particular to a compact mechanical device capable of holding an automotive door in a number of predetermined open positions with a predetermined force.

DESCRIPTION OF THE PRIOR ART

It has been found useful to check the movement of an automotive door in a number of predetermined open positions to assure convenient and safe ingress/egress of the occupants. The door is normally checked against movement in at least one open position with an effort or resistive force adequate to resist wind gusts and the effect of parking on an incline or grade.

The most common form of automotive door check apparatus is a mechanical device that resists motion by releasably storing energy in response to forced motion of the system. These devices, located between the vehicle's body structure and door, can be configured to be integral with the door hinge or separate as autonomous mechanical assemblies. Energy storage is generally achieved by a form of spring with coil and torsion arrangements being the most popular configurations. As the door is opened or closed, the door check apparatus is configured to release energy entering the check positions and to store it when moving out of the check positions. The most common method of storing energy in the spring system is by means of a cam arrangement that moves in conjunction with the door. This cam can work within the hinge to ultimately produce a torque around the pivot axis of the hinge, or can work linearly in a separate checking apparatus which produces a force vector to resist door movement at selected opening positions.

US5173991 to Carswell describes a common type of separate door checking apparatus that utilizes a molded link member to provide a cam arrangement and a pair of coil springs to releasably store energy. The coil springs are contained in a check housing and are acted upon by the molded link member via ball bearings and ball bearing retainers. The check housing is rigidly attached to the vehicle door and the molded link member is pivotally connected to the vehicle body structure. The device of Carswell provides a robust, reliable and relatively compact solution for checking the movement of an automotive door. There are numerous similar solutions that utilize rollers or sliders in place of the ball bearings of Carswell. US6370733 to Paton et. al. describes a separate checking apparatus that utilizes a molded link member or check arm and rollers. US6842943 to Hoffmann et. al. describes a separate checking apparatus that utilizes a molded check arm and sliders.

Because the automotive door check apparatus must be located between the vehicle's body structure and door, it is forced to occupy a severely restricted package space as there is limited clearance between the vehicle body structure and the door and very

little volume available within the door. Additionally, the weight of the automotive door check apparatus must not be too great as a significant proportion of the door check apparatus mass resides within the door profile, which swings on a pivot and is highly sensitive to weight. In general, the manufacturing costs of automotive components are among the lowest of any comparable industry and so simple solutions with low part counts are highly desirable. The main focus of an automotive door check development is to attain the required check efforts in the smallest possible package at the lowest achievable weight and cost. Using as few components as possible is highly desirable. The type of spring and its related strain energy storage capability combined with the package efficiency of the actuation mechanism ultimately dictate the overall effectiveness of the automotive door check apparatus.

GENERAL DESCRIPTION OF THE INVENTION

Accordingly, it would be advantageous to create an automotive door check apparatus that provides identical functional performance to the prior art configurations but does so with fewer components and moving parts than these existing arrangements.

The present invention reduces the complexity, weight and cost of an automotive door check apparatus by combining the functions of the check housing and mounting bracket with that of the energy storage device. This combining of functions eliminates the requirement for separate springs, multiple piece check housings and ball bearings, rollers or sliders as utilized by the prior art devices. The door check apparatus of the present invention is reduced to two moving parts from a minimum of seven in the prior art arrangements.

The present invention replaces the check housing, mounting bracket and springs of the conventional prior art automotive door check apparatus with a single piece unitary check body manufactured from a resilient material capable of storing and releasing energy. This unitary check body is rigidly attached to the vehicle door via a mounting face and is configured with a pair of compliant leaves and a guidance arrangement. A check arm is configured with detent features and cam surfaces and is adapted to pivotally connect to the vehicle body structure and pass into the vehicle door through a suitable access opening. The unitary check body is rigidly attached to the vehicle door at the access opening. The check arm is adapted to move through the unitary check body and slideably interface with the guidance arrangement in response to rotary motion of the vehicle door relative to the vehicle body structure. This relative rotary motion is checked with predetermined forces at positions determined by the relationship between the detent features of the check arm relative to the guidance arrangement of the unitary check body. The predetermined check forces are generated from the energy stored and released by the compliant leaves of the unitary check body. The compliant leaves of the unitary check body store and release energy in response to the motion of the guidance arrangement as it is forced to follow the profile of the detent features and cam surfaces of the check arm as the check arm moves through the unitary check body. As is common in the art, the predetermined check forces act primarily along the centerline axis of the check arm and the check

arm is installed with an offset to the hinge swing centerline so as to induce a checking moment to resist relative rotary motion between the vehicle door and vehicle body structure. In this manner the automotive door check apparatus of the present invention provides identical check force and moment generation to the devices of the prior art with only two primary components.

In a further aspect of the present invention the check arm is configured with a pivot boss and is pivotally connected to a mounting bracket via a pivot rivet. The mounting bracket is then rigidly mounted to the vehicle body structure via bolting, welding, bonding, riveting or similar fastening means.

In a preferred embodiment of the present invention the check arm is formed from a moldable plastic material and contains a metallic reinforcement co-molded within the plastic material.

In a further aspect of the present invention the check arm is configured with a bump stop that is adapted to pass through the guidance arrangement of the unitary check body with no contact. The vehicle door is prevented from further rotation at its full open swing limit by the bump stop contacting the unitary check body at its mounting face. In this manner the stop loads associated with preventing further rotation of the vehicle door are transferred directly to the vehicle door structure rather than through the unitary check body. This allows the unitary check body to be optimized for the single function of generating the predetermined checking forces via the compliant leaves rather than also being required to carry full open stop loads. This bump stop arrangement is a primary differentiator over the prior art in which the check housings are configured to withstand the full open swing limit stop loads.

In a preferred embodiment of the present invention an energy absorber is incorporated into the bump stop of the check arm so that when it contacts the backside of the mounting face of the unitary check body the kinetic energy carried by the moving vehicle door is dissipated. By dissipating the kinetic energy in a controlled manner the vehicle door is prevented from bouncing closed when it reaches the full open swing limit.

In an additional aspect of the present invention the check arm is adapted to accept a paint clip device that is configured with additional detent features and cam surfaces. The paint clip device is configured to provide additional check positions as required during the paint and assembly process of the vehicle. The paint clip device is configured to be easily removable from the check arm after the paint and assembly process. In this way the automotive door check apparatus of the present invention is capable of providing a temporary check position at the vehicle door full closed limit to facilitate painting prior to the door latch being installed.

In a preferred embodiment of the present invention the unitary check body is manufactured from a high strength steel or a similar compliant but strong material. The mechanical properties of this resilient material, the geometric configuration of

the compliant leaves and the profile shape of the detent features and cam surfaces are configured so that the resilient material never exceeds its elastic limit within the operating range of the automotive door check apparatus.

In further aspects of the present invention: a) the unitary check body contains a pair of compliant leaves and a guidance arrangement, and is adapted to be rigidly mounted to a vehicle door via bolting, welding, bonding, riveting or similar fastening means; b) the unitary check body is manufactured from a high strength steel so that the compliant leaves are capable of storing and releasing energy; c) the check arm contains a bump stop, cam surfaces and detent features, and is pivotally connected to the vehicle body structure via a mounting bracket and pivot rivet arrangement and configured to slideably interface with the guidance arrangement of the unitary check body; d) the check arm is formed from a moldable plastic material and contains a reinforcement co-molded within the plastic material; e) the bump stop feature incorporates an energy absorbing material co- molded with the plastic material of the check arm; f) the mounting bracket is rigidly mounted to the vehicle body via bolting, welding, bonding, riveting or similar fastening means; such that rotary motion of the vehicle door relative to the vehicle body structure is checked with predetermined forces generated from the energy stored and released by the compliant leaves of the unitary check body, at positions determined by the relationship between the detent features of the check arm relative to the guidance arrangement, and the vehicle door is prevented from further rotation at its full open swing limit by the bump stop feature contacting the unitary check body at its mounting surface so that stop loads associated with preventing further rotation are transferred directly to the vehicle door structure, and the vehicle door is prevented from bouncing closed by the energy absorbing material.

Further aspects of the invention will become apparent from the following description. BRIEF DESCRIPTION QF THE DRAWINGS

FIG. 1 is a perspective view of the inventive automotive door check apparatus;

FIG. 2 is a perspective view of the inventive automotive door check apparatus in a typical automotive installation;

FIG. 3 is a plan view of the check arm of the inventive automotive door check apparatus;

FIG. 4 is a plan view of the inventive automotive door check apparatus shown with the vehicle door at its full open swing limit;

FIG. 5 is a perspective view of the check arm of the inventive automotive door check apparatus showing partial interior detail;

FIG. 6 is a perspective view of an alternative embodiment of the inventive automotive door check apparatus;

FIG. 7 is a perspective view of a further alternative embodiment of the inventive automotive door check apparatus including a paint clip device;

FIG. 8 is a perspective view of a further alternative embodiment of the inventive automotive door check apparatus illustrating removal of the paint clip device;

FIG. 9 is a perspective view of a further alternative embodiment of the inventive automotive door check apparatus with the paint clip device removed.

DETAILED DESCRIPTION OF THE INVENTION

Referring to Figures 1 and 3, an automotive door check apparatus (1) consists of a unitary check body (10) and a check arm (30). The unitary check body (10) is configured with a mounting face (12), a pair of compliant leaves (14), a guidance arrangement (16) and at least one mounting fastener (18). The check arm (30) is configured with a pivot boss (32), a mounting bracket (34), a pivot rivet (36), detent features (38), cam surfaces (39) and a bump stop (40). Referring to Figures 1 and 2, the unitary check body (10) is adapted to rigidly attach to a vehicle door (2) via its at least one mounting fastener (18). The check arm (30) is adapted to rigidly mount to a vehicle body structure (3) via its mounting bracket (34) and at least one attachment fastener (48). The check arm (30) is configured to rotate around its pivot rivet (36) and to move through the unitary check body (10) and slideably interface with the guidance arrangement (16).

Relative rotary motion between the vehicle door (2) and vehicle body structure (3) causes the check arm (30) to move through the unitary check body (10) and slideably interface with the guidance arrangement (16) forcing the compliant leaves (14) to move in response to the cam surfaces (39) and detent features (38) of the check arm (30).

The unitary check body (10) is manufactured from a resilient material capable of storing and releasing energy while generating predetermined contact forces in response to the displacement of the compliant leaves (14). The mechanical properties of the resilient material, geometric configuration of the compliant leaves (14) and profile shape of the detent features (38) and cam surfaces (39) are configured so that the resilient material never exceeds its elastic limit within the operating range of the automotive door check apparatus (1). In a preferred embodiment of the present invention the unitary check body (10) resilient material is a high strength steel. In an alternative embodiment of the present invention the unitary check body (10) resilient material is a high strength composite or a similar compliant but strong material.

When the check arm (30) moves through the unitary check body (10) it slideably interfaces with the guidance arrangement (16) and the compliant leaves (14) move into the detent features (38) releasing energy and lowering their contact forces. As the check arm (30) continues to move through unitary check body (10) and slideably interface with the guidance arrangement (16) the complaint leaves (14) move out of the detent features (38) and up onto the cam surfaces (39) increasing their contact

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forces and storing energy. The contact forces in combination with the profile shape of the detent features (38) generate predetermined checking forces along the axis of the check arm (30). Relative rotary motion of the vehicle door (2) and the vehicle body structure (3) is checked by the predetermined checking forces at positions determined by the relationship between the detent features (38) of the check arm (30) relative to the guidance arrangement (16).

In a preferred embodiment of the present invention the check arm (30) is formed from a moldable plastic material which integrally includes the detent features (38), cam surfaces (39), pivot boss (32) and bump stop (40). Referring to Figure 5, a further aspect of the preferred embodiment is illustrated in which the molded plastic check arm (30) contains a co-molded reinforcement (44) manufactured from steel, aluminum, reinforced plastic or a similar structural material.

Figure 4 illustrates a further aspect of the door check apparatus, showing the vehicle door (2) at its full open swing limit and the bump stop (40) in contact with the backside of the mounting face (12) of the unitary check body (10). Further rotation of the vehicle door (2) is prevented by the bump stop (40) transferring the stop loads directly from the check arm (30) into the vehicle door structure through the single material thickness of the mounting face (12) of the unitary check body (10). The short load path between the bump stop (40) and vehicle door structure allows the unitary check body (10) to be optimized for the single function of generating the predetermined checking forces via the compliant leaves (14) rather than also being required to carry full open stop loads. This bump stop arrangement is a primary differentiator over the prior art in which the check housings are configured to withstand the full open swing limit stop loads.

A preferred embodiment of the bump stop (40) of the check arm (30) is illustrated in Figure 6. An energy absorber (42) is incorporated into the bump stop (40) so that when it contacts the backside of the mounting face (12) of the unitary check body (10) the kinetic energy carried by the moving vehicle door (2) is dissipated thereby preventing the vehicle door (2) from bouncing closed when it reaches the full open swing limit. In a further aspect of this preferred embodiment, the energy absorber (42) is co-molded with check arm (30).

As illustrated in Figures 7, 8 and 9, in a further aspect of the present invention, the check arm (30) is adapted to accept a paint clip device (46) that is configured with additional detent features (58) and cam surfaces (59). The paint clip device (46) is configured to provide additional check positions as required during the painting and assembly process of the vehicle. The paint clip device (46) is configured to be easily removable from the check arm (30) after the painting and assembly process. Figure 8 illustrates the paint clip device (46) being removed from the check arm (30) using a screwdriver (55) to pry it free and Figure 9 shows the check arm (30) with the paint clip device (46) completely removed. In this way the automotive door check apparatus (1) of the present invention is capable of providing a temporary check

position at the vehicle door (2) full closed limit to facilitate painting prior to the door latch being installed.