CURB CUSHION

This application is being filed on 14 June 2007, as a PCT

International Patent application in the name of Dwight R. GUNNARSON, a U.S. citizen, and Larry J. THOMSEN, a U.S. citizen, applicants for the designation of all countries, and claims priority to U.S. Utility Patent Application Serial No. 1 1/475,473 filed on 27 June 2006.

Technical Field

The disclosure relates to a device for protecting a surface from damage caused by wheels or tracks of motor vehicles and a method of manufacturing thereof. More particularly, the device includes a cushion that can be configured to protect a curb from damage.

Background of the Invention

It is routinely necessary for heavy vehicles such as dozers, excavators, and dump trucks to traverse raised cement edges along roads commonly referred to as curbs. Curbs often crack or crumble due to the load applied to them via the wheels or tracks of the vehicles.

To protect the curbs, people sometimes cover the curb or fill the transition area between the streets and curb with wood, dirt, or other readily available materials such as tires. In other instances rigid ramps are used to transition between the road surface and the top surface of the curb. Covering the curb and filling in the transition area with available pieces of wood and other random materials yield inconsistent and unreliable results. Often the force from the tires and tracks of the vehicles is transmitted through such protective materials and the curb is nonetheless damaged. It is also common that the protective materials slide away from the curb area as the vehicles traverse the curb, thereby leaving the curb exposed and susceptible to damage.

Protecting the curb by placing dirt over the curb and in the transition area can be effective. However, using dirt to protect the curb can be overly time- consuming, cumbersome, and messy. Protecting the curb with dirt requires that the operators excavate dirt, place it over the curb area, and remove the dirt after the vehicle has traversed over the curb.

Ramps have also been used to protect curbs. An exemplary ramp is disclosed in U.S. Patent No. 5,836,028 (Petersen). The disclosed ramp comprises a rigid construction, which is typical with ramps. Because curb shapes and sizes vary, it is unlikely that any particular rigid ramp can be effectively used to protect different curbs. In addition, since ramps are typically rigid, the forces ramps apply to the road surfaces can be concentrated rather than distributed, thereby causing them to perform poorly. Furthermore, since ramps are designed to support the weight of a heavy vehicle, they arc typically very heavy and difficult to transport and manipulate. There is a need in the art for a method and device for protecting curbs from damage that is more streamline, efficient, and clean.

Summary of the Invention

The disclosure is directed to a device and method for transporting heavy construction equipment over two surfaces separated by an obstacle, such as a curb or a gutter. The device is a cushion that according to some embodiments is constructed of a deformable and resilient material. According to one embodiment, the cushion is positioned at least partially in the transition area between the road surface and the raised curb and over a portion of the upper surface of the curb. The curb cushion protects the curb and also functions as a ramp for facilitating the passing of vehicles over a curb. Given the functionality of the curb cushion it is particularly advantageous for use with heavy vehicles; however, it can be advantageously used with light vehicles such as passenger vehicles and light trucks.

Brief Description of the Drawings

Figure 1 is a perspective view of a curb cushion according to an embodiment of the invention;

Figure 2 is a perspective view of a pair of curb cushions of Figure 1 positioned for use to traverse a first obstacle;

Figure 3 is a perspective view of a pair of curb cushions of Figure 1 positioned for use to traverse a second obstacle; Figure 4 is a side elevation view of the curb cushion of Figure 1 over a third obstacle;

Figure 5 is a side elevation view of the curb cushion of Figure 4 under a wheeled vehicle;

Figure 6 is a side elevation view of the curb cushion of Figure 4 under a tracked vehicle; and Figure 7 is a side elevation view of a curb cushion of Figure 1 over a fourth obstacle and under a tracked vehicle.

Detailed Description of the Preferred Embodiment

The cushion according to the invention is constructed to protect various structures from surface damage while heavy construction vehicles are traveling over them. Referring to Figure 1, the cushion is shown as curb cushion 10 that can be used to protect concrete curb and gutter structures located on most streets and parking lots. The curb cushion includes a top 11, a bottom 13, a first end portion 15, and a second end portion 17. Referring to Figures 2 and 3, the curb cushion 10 of Figure 1 is shown used with other like curb cushions to protect a first obstacle 12 in Figure 2 and a second obstacle 14 in Figure 3.

Referring to Figure 2, the first obstacle 12 is shown as a set-up type curb 16 that is commonly found along residential streets. The curb includes a lower surface 18 that abuts the road surface (not shown), an upper surface 20 that abuts the lawn or sidewalk 22, and a transition surface 24 that connects the upper surface 20 and lower surface 18. Variations of such curb profiles are numerous including, for example, "B6" Style curb (B612 or B618), "D" Style curbs ( D412, D418, D612, D618), or any surmountable curb styles. The word curb used herein is not intended to include or exclude any style of curb. It is used only to refer to the structure typically found adjacent the edges of a road surface. Still referring to Figure 2, the curb cushions 10 are shown parallel and spaced apart to align with the wheels or tracks of a vehicle (not shown).

Referring to Figure 3, four curb cushions 10 are used to protect the second obstacle 14. The curb cushions are position such that they protect the front corner 26 and rear corner 28 of the obstacle 14. Like in Figure 2, the curb cushions .10 are spaced apart and aligned to engage the tires or tracks of a vehicle (not shown). It should be appreciated that the curb cushion 10 may also be used in other applications, such as to provide a ramp and protection over footings and foundations

of structures, or a ramp and protection over rigid pipes and sidewalks. The term curb cushion is used instead of simply cushion because protecting curbs is a common application of the cushion according to the present disclosure.

Referring to Figure 4, the curb cushion 10 is shown over a third obstacle 30. The third obstacle is a curb that includes a lower surface 32, an upper surface 34, and a transition surface 36. The curb shown includes two major stress points 38 and 40. The major stress points 38 and 40 of the depicted curb are located at an extreme edge of the back of the curb and the extreme edge of the front or face of the curb, respectfully. Due to the particular geometric configuration of the curb, it has a tendency to fail (e.g., chip, crack, and/or crumble) at the major stress points 38 and 40 when heavy vehicles (being wheeled or tracked) travel over the curb.

Still referring to Figure 4, the curb cushion 10 is shown in a static state (i.e., in a normal unloaded state). The first end portion 15 extends over the lower surface 32 of the curb and the second end portion 17 extends over the upper surface of the curb. The first and second end portions 15 and 17 include proximal and distal ends. The distal ends 19 and 21 of the first and second end portions 15 and 17 are coincident with the ends of the curb cushion 10 and the proximal ends of the first and second end portions 15 and 17 are where the first and second end portions 15 and 17 join together in the center of the cushion 10. According to the depicted embodiment, the major stress points 38 and 40 are covered by the curb cushion 10. The first end portion 15 covers stress point 40 and the second end portion 17 covers stress point 38.

In the depicted embodiment the first end portion 15 extends over the road surface by one or more inches. The bottom surfaces of the first and second end portions 15 and 17 are shown offset by between 4 to 10 inches. The top 11 includes a first ramped surface 23 that slopes up from the distal end of the first end portion 15 and a second ramped surface 25 that slopes up from the distal end of the second end portion 17. A transition surface 27 connects the ramped surface over the proximal ends of the first and second end portions 15 and 17. In the depicted embodiment the distance Dl between the bottom 13 and top 11 in the transition area in its normal state is between 2 to 12 inches. It should be appreciated that in alternative embodiments, many geometric constructions and dimensions are possible. For

example, the first end portion 15 may not extend over the road surface and the top 11 could, for example, instead include a single curved profile.

The curb cushion 10 includes a plurality of cutouts 42 on its underside 13. The cutouts 42 define a stability core 44 that is positioned between the first end 15 and second end 17 of the curb cushion 10. The stability core 44 provides structural stability for the vehicle even when the curb cushion 10 is at its most deformed state, thereby keeping the vehicle elevated above the surface of the curb 30 at all times, minimizing any force concentration between the wheels or tracks of the vehicle and the surfaces of the curb 30. In the depicted embodiment, the curb cutouts 42 are parallel to each other and run across the width of the curb cushion 10. In addition, in the depicted embodiment the cutouts 42 are angled in a direction away from the bottom surface of the first end portion 15 towards the top 1 1 and second end portion 17 of the curb cushion 10. It should be appreciated that many other alternative cutout arrangements are also possible. Still referring to Figure 4, a relief contour 46 is shown on the underside of the second end of the curb cushion. The relief contour 46 provides a locking feature that keeps the curb cushion 10 in position as the vehicle maneuvers over the curb 30. In addition, the curb cutouts 42 also lessen weight, enable water to flow under the curb cushion 10, and serve as handles for easy lifting and manually transporting the curb cushion. The cutouts 42 and relief contour 46 add flexibility to the curb cushion 10 and enable the curb cushion to predictably deform when loaded.

Referring to Figure 5, the curb cushion 10 of Figure 4 is shown in a dynamic state where a load is applied to the top 11 of the curb cushion 10 via a wheel 50 of a vehicle (not shown). The wheel applies a relatively concentrated force 51 downward into the curb cushion 10 towards the curb 30. The curb cushion 10 deforms to fit the surface profile of the curb 30 and transmits the force 51 from the wheel 50 more evenly along the surface 36 of the curb 30 as shown by arrows 53. By distributing the force 51 across the surface of the curb 30 more evenly, the curb is less likely to be damaged by the wheel 50 of the vehicle. In addition to preventing failure of the curb 30, the curb cushion 10 acts as a ramp to facilitate the passing of the vehicle over the curb 30.

Referring to Figure 6, the curb cushion of Figure 4 is shown in a dynamic state where a load is applied to the top of the curb cushion 10 via the track

downward force 61 applied from the track 60 is distributed across the top surface 11 of the curb cushion. The curb cushion deforms to the space between the track and the curb 30 and distributes the force 61 of the track 60 across the surface profile of the curb 30 shown by arrows 63. If the curb cushion 10 was not positioned between the track 60 and the curb 30, the track would apply a concentrated force at localized areas of the surface of the curb 30, which would likely lead to failure of the curb surfaces 32, 34, 36. Like in Figure 5, the curb cushion 10 redistributes and evens out the force applied from the vehicle onto the curb 30 to help prevent curb 30 from failure.

Referring to Figure 7, the curb cushion 10 of Figure 1 is shown over a curb 70 that has a different surface profile as compared to curb 30. However, like curb 30 curb 70 includes major stress points 71 and 72 that are defined as locations on the curb that arc most susceptible to failing. The curb cushion 10 extends over the major stress points 71 and 72. The curb cushion 10 protects the curb by deforming and redistributing the force across the surface of the curb 70. The cutouts 42 and relief contour 46 arc constructed to enable the curb cushion to predictably deform and be adaptable for use on a wide range of different curb profiles. The cutouts 42 and relief contour 46 also help keep the curb cushion 10 relatively stationary when the vehicle moves across the top 11 of the curb cushion 10, as the curb cushion tends to deform when engaged by the track 60 or wheel 50 rather than slide away as would a more rigid object. It should be appreciated that though four cutouts 42 and one relief contour 46 are shown, an alternative embodiment of the curb cushion 10 may include any suitable number of cutouts 42 are relief contours 46.

Referring back to Figure 4, the depicted embodiment is sized to work well with most curb structures which are between 16 to 32 inches in width C. To work with most curb and gutter structures the overall length L2 of the curb cushion 10 is preferably between 36 to 48 inches long and most preferably 40 inches long. The width W is preferably between 12 to 24 inches wide and most preferably 18 inches wide (see Figure 3). The height H is between 8 to 12 inches and most preferably 10 inches high. It should be appreciated that the curb cushion can be

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manufactured in other geometric orientations and sizes as appropriate for its intended application(s).

In the depicted embodiment the curb cushion 10 is molded out of a flexible material such as dense urethane foam, dense rubber product, or a combination of both. In alternative embodiments the curb cushion 10 can be constructed of other deformable materials or from a combination of materials, some being more deformable than others. For example, in an alternative embodiment the top 11 of the curb cushion 10 could be constructed of a harder plastic material that is adhered to the body portion of the curb cushion to protect the top 11 against abrasion. Preferably, the curb cushion is constructed such that it is heavy enough to maintain position over the curb and gutter, yet light enough to be easily transported by an individual. The preferred design weight is 25 to 50 pounds per cushion. The above specification, examples, and data provide a complete description of the manufacture and use of the composition of the invention. Since many embodiments of the invention can be made without departing from the spirit and scope of the invention, the invention resides in the claims hereinafter appended.