Rate stiffening jounce bumper assembly
The present invention provides a rate stiffening jounce bumper assembly, including a cup member having a large-headed mushroom stud which is inserted into the cup-shaped member and overmolded with an elastomeric bumper material. The head portion of the mushroom stud forms a shelf against which the bumper material is compressed such that the head portion effectively shortens the bumper spring thereby providing a stiffer spring rate to be obtained with a taller jounce bumper assembly.
1. A jounce bumper assembly comprising:
a generally cup-shaped member having a base portion and a sidewall portion extending from said base portion and defining a cavity, said base portion including a mounting aperture therein;
a stud extending through said mounting aperture and having a shoulder including an axially directed face disposed against said base portion and a radially extending head portion axially spaced from said axially directed face of said shoulder and disposed in said cavity, said head portion having a diameter larger than a diameter of said shoulder;
a bumper molded within said generally cup-shaped member and extending around said head portion, said bumper extending from said cup.
2. The jounce bumper assembly of claim 1 , wherein said head portion has a diameter equal to at least one half a diameter of said sidewall portion.
3. The jounce bumper assembly of claim 1 , wherein a top surface of said head portion is spaced from said base portion by a distance between one-third and two-thirds of a height of said generally cup-shaped member.
4. The jounce bumper assembly of claim 1 , wherein said sidewall portion of said generally cup-shaped member has a plurality of openings therein.
5. The jounce bumper assembly of claim 1 , wherein said generally cup-shaped member includes a plurality of radially inwardly extending tabs disposed adjacent to said head portion of said stud.
6. The jounce bumper assembly of claim 1 , wherein said generally cup-shaped member is made from metal.
7. The jounce bumper assembly of claim 1 , wherein said bumper is formed of a material selected from at least one of a group consisting of solid and foamed elastomeric materials.
8. A jounce bumper assembly for a wheel suspension system of a vehicle including a frame member and a strut member displaceable relative to said frame member along a line of travel, comprising:
a generally cup-shaped member having a base portion and a sidewall portion extending from said base portion and defining a cavity, said base portion including a mounting aperture therein;
a stud extending through said mounting aperture and having a shoulder including an axially directed face disposed against said base portion and a head portion axially spaced from said shoulder and having a surface facing in an opposite direction from said axially directed face of said shoulder and disposed in said cavity, a top surface of said head portion being axially spaced from said base portion by a distance between one-third and two-thirds of a height of said generally cup-shaped member;
a bumper disposed within said generally cup-shaped member and extending around said head portion , said bumper extending from said cup-shaped member.
9. The jounce bumper assembly of claim 8 , wherein said head portion has a diameter equal to at least one half a diameter of said sidewall portion.
10. The jounce bumper assembly of claim 8 , wherein said sidewall portion of said generally cup-shaped member has a plurality of openings therein.
11. The jounce bumper assembly of claim 8 , wherein said generally cup-shaped member includes a plurality of radially inwardly extending tabs disposed adjacent to said head portion of said stud.
12. The jounce bumper assembly of claim 8 , wherein said generally cup-shaped member is made from metal.
13. The jounce bumper assembly of claim 8 , wherein said bumper is formed of a material selected from at least one of the group consisting of solid and foamed elastomeric materials.