Fences – Highway guard
Reexamination Certificate
1998-04-22
2001-01-16
Kim, Harry C. (Department: 3629)
Fences
Highway guard
C404S006000
Reexamination Certificate
active
06173943
ABSTRACT:
BACKGROUND
The present invention relates to guardrails of the type that are placed alongside a roadway to redirect a moving vehicle that has left the roadway.
Modern guardrails are relied on for two separate functions that are to some extent in tension with one another. First, the guardrail preferably has adequate tensional strength in the longitudinal direction that a vehicle striking an intermediate portion of the guardrail at an oblique angle will be prevented from passing through the guardrail and redirected along the length of the guardrail. This function requires considerable tensional strength.
Second, the guardrail preferably slows a vehicle that strikes the end of the guardrail at a suitable rate such that excessive decelerations are not applied to the vehicle and the guardrail does not impale the vehicle.
Various prior-art approaches have been suggested for accommodating these two separate functions of guardrail design. See for example, Sicking U.S. Pat. Nos. 5,547,309 and 5,407,298, Mak U.S. Pat. 5,503,495, and U.S. patent application Ser. No. 08/990,468 (U.S. Pat. No. 5,967,497), filed Dec. 15, 1997, assigned to the assignee of the present invention.
The present invention is directed to improvements in guardrails that further reduce any tendency of the guardrail to impale an impacting vehicle while maintaining a desired level of longitudinal tensional strength.
SUMMARY
The present invention is defined by the following claims, and nothing in this section should be taken as a limitation on those claims.
By way of introduction, the preferred embodiment described below includes a guardrail having an array of vehicle-deflecting rails secured to an array of posts. This embodiment further includes an impact-receiving element that is slidably mounted to the forward end of the first rail. This impact-receiving element includes a vehicle-engaging portion having a frontal area substantially greater than the frontal area of the end of the first rail. Because the impact-receiving element is slidably mounted to the first rail, an impacting vehicle initially accelerates the impact-receiving element, without substantially accelerating or deforming the remaining rails. Since the frontal area of the impact-receiving element is substantially greater than that of the first rail, impact forces on the vehicle are spread. These two features cooperate to reduce any tendency of the guardrail to impale the vehicle.
REFERENCES:
patent: 4678166 (1987-07-01), Bronstad et al.
patent: 4928928 (1990-05-01), Buth et al.
patent: 5022782 (1991-06-01), Gertz et al.
patent: 5078366 (1992-01-01), Sicking et al.
patent: 5391016 (1995-02-01), Ivey et al.
patent: 5407298 (1995-04-01), Sicking
patent: 5503495 (1996-04-01), Mak
patent: 5547309 (1996-08-01), Sicking
patent: 5775675 (1998-07-01), Sicking et al.
patent: 5791812 (1998-08-01), Ivey
patent: 5797591 (1998-08-01), Krage
patent: 5957435 (1999-09-01), Bronstad
patent: 5967497 (1999-10-01), Denman et al.
patent: 6022003 (2000-02-01), Sicking et al.
Denman Owen S.
Welch James B.
Brinks Hofer Gilson & Lione
Energy Absorption Systems, Inc.
Kim Harry C.
LandOfFree
Guardrail with slidable impact-receiving element does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Guardrail with slidable impact-receiving element, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Guardrail with slidable impact-receiving element will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2453795