Bolster spring suspension assembly
A bolster spring assembly is adapted for securement to a vehicle having a primary suspension system for securing an axle to the vehicle. The bolster spring assembly is located and secured between the leaf spring over the axle and the undercarriage of the vehicle as a supplement to the primary suspension system.
Latest E-Z-Ride Corp. Patents:
This Application is a continuation of U.S. patent application Ser. No. 10/726,318 filed Dec. 2, 2003 which claims the benefit of Provisional U.S. Patent Application No. 60/482,956 filed Jun. 27, 2003 by Howard E. Sellers.
BACKGROUND OF THE INVENTION1. Field of the Invention
The invention relates to a suspension system assembly for use with a leaf spring suspension system.
2. Discussion of Prior Art
In vehicle suspension systems, the use of leaf springs and bolster springs is well known. For example one such use of a bolster spring is described in U.S. Pat. No. 5,676,356 to Ekonen. Ekonen discloses a suspension system in which a leaf spring is carried by the undercarriage of the vehicle. A bolster spring is connected between each end of the leaf spring and the underlying end of the axles.
Another example of a vehicle suspension system that utilizes both a leaf spring and a bolster spring is described in U.S. Pat. No. 6,079,723 to Choi. Choi discloses a suspension assembly for a vehicle having a leaf spring with a mounting block affixed to the end of the leaf spring. The mounting block is attached to a bolster spring, and the bolster spring is mounted to the vehicle frame with a bracket.
Both the Ekonen and Choi disclosures combine a leaf spring with a bolster spring to produce a suspension system that provides a smoother ride. However, in both of these disclosures the bolster spring is an integral part of the overall suspension system and can not be easily added to the system as an aftermarket item. It would be desirable, however, to have a method of retrofitting or mounting a bolster spring to an existing leaf spring suspension system without having to completely redesign the entire suspension system.
In early developments leading up to the invention, a layered rubber bolster spring was substituted for the hanger arm at the rear of a leaf spring such that the bolster spring was compressed to accommodate the upwardly flexing of the leaf spring that occurs when the wheel goes over a bump. This, however, provided unsatisfactory results in that it did not control the jounce, or roll of the vehicle chassis in relation to the axle, as well as desired. In addition, it required substantial modification of the entire suspension system.
SUMMARY OF THE INVENTIONA bolster spring suspension assembly is disclosed in which a bolster spring is adapted for mounting to a vehicle between the axle and the undercarriage as a supplement to a second suspension element securing the axle to the vehicle.
One object of the invention is to provide an improved suspension system for providing a smoother ride. Another object of the invention is to provide a way to modify an existing leaf spring suspension to provide a smoother ride. A further object of the invention is to provide a suspension system that reduces jounce.
BRIEF DESCRIPTION OF THE DRAWINGSThese and other aspects of the invention will be apparent from the following description, with reference to the accompanying drawings, in which:
Referring now to the drawings, a vehicle as partially shown in
Suspension assembly 28 as shown in
As best shown in
Bolster spring suspension assembly 28 may be either installed as original equipment or easily retrofitted or attached to an existing leaf spring suspension system. When retrofitting suspension assembly 28 to an existing leaf spring suspension, the original mounting brackets for U-bolts 26 are removed and appropriate holes for bolts 44 are formed in frame member 16. A backing plate 48, best seen in
The description given herein is not considered to be a limitation on other minor and obvious variations, but is only meant to exemplify and encompass the full scope of the invention as set forth in the claims.
Claims
1. A bolster spring configured to be attached to a suspension system of a vehicle including a leaf spring connecting an axle to a frame of the vehicle, the bolster spring being configured to supplement the support provided by the suspension system, and the bolster spring comprising:
- a first end connected to the axle;
- a second end connected to the vehicle frame;
- a plurality of resilient core members located intermediate said ends; and
- a plurality of separator plates, positioned so that at least one of said separator plates is located intermediate a pair of adjacent resilient core members;
- wherein said bolster spring is positioned so that said separator plates are arranged at an angle within a range of about 5° to about 25° with respect to a substantially vertical axis.
2. The bolster spring as set forth in claim 1, further comprising a first bracket connected to said first end and a second bracket connected to said second end.
3. The bolster spring as set forth in claim 2, wherein said first bracket is offset vertically and laterally from said second bracket.
4. The bolster spring as set forth in claim 3, wherein said first bracket includes a pair of mounting holes configured to receive a U-bolt connected to the axle.
5. The bolster spring as set forth in claim 4, wherein said first bracket includes a horizontal plate positioned adjacent to the leaf spring and a vertical plate connected to said bolster spring.
6. The bolster spring as set forth in claim 1, wherein said second end is located vertically above said first end.
7. The bolster spring as set forth in claim 1, wherein said bolster spring is configured to allow only one bolster spring to connect to both the frame and the leaf spring.
8. A suspension system for attaching an axle to a vehicle frame comprising:
- a leaf spring fixed to the frame at a first point and joined by a linkage to the frame at a second point; and
- a bolster spring assembly fixed to the frame at a third point and connected to the leaf spring at a fourth point, said bolster spring assembly comprising at least one bolster spring being longitudinally offset from said fourth point, said bolster spring assembly acting in both shear and torsion.
9. The suspension system for attaching an axle to a vehicle frame as set forth in claim 8, wherein said bolster spring assembly includes only one said bolster spring.
10. The suspension system for attaching an axle to a vehicle frame as set forth in claim 8, wherein said third point is located vertically above said fourth point.
11. The suspension system for attaching an axle to a vehicle frame as set forth in claim 10, wherein said third point is located forward of said fourth point.
12. The suspension system for attaching an axle to a vehicle frame as set forth in claim 8, further including a first bracket and a second bracket, said first bracket connected to said bolster spring at said third point and said second bracket connected to said bolster spring at said fourth point.
13. The suspension system for attaching an axle to a vehicle frame as set forth in claim 12, further including a U-bolt configured to connect said second bracket to the axle.
14. The suspension system for attaching an axle to a vehicle frame as set forth in claim 8, wherein said bolster spring assembly includes a plurality of resilient core members located intermediate said third point and said fourth point and a plurality of separator plates, positioned so that at least one of said separator plates is located intermediate a pair of adjacent resilient core members; wherein said bolster spring assembly is positioned so that said separator plates are arranged at an angle within a range of about 5° to about 25° with respect to a substantially vertical axis.
15. The suspension system for attaching an axle to a vehicle frame as set forth in claim 14, wherein said cores and said separator plates are generally vertically disposed and said third point is spaced apart forwardly and upwardly from said fourth point.
16. The suspension system for attaching an axle to a vehicle frame as set forth in claim 8, wherein said bolster spring assembly extends in the direction of said first point.
17. The suspension system for attaching an axle to a vehicle frame as set forth in claim 16, wherein said bolster spring assembly is located vertically above said axle.
18. The suspension system for attaching an axle to a vehicle frame as set forth in claim 17, further including a bracket connecting said leaf spring to said frame.
19. The suspension system for attaching an axle to a vehicle frame as set forth in claim 18, wherein said bracket retains said leaf spring in a relatively fixed position with respect to said frame.
20. The suspension system for attaching an axle to a vehicle frame as set forth in claim 19, wherein the linkage allows for substantially horizontal movement of the leaf spring with respect to the frame at said second point.
Type: Application
Filed: May 15, 2007
Publication Date: Feb 7, 2008
Applicant: E-Z-Ride Corp. (Milford, IN)
Inventor: Howard Sellers (Milford, IN)
Application Number: 11/803,610
International Classification: B60G 5/00 (20060101);