US4600636A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Core material for an automobile bumper
Assignee: JAPAN STYRENE PAPER Corp A CORP OF JAPAN
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Filing: 1985-03-06
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Granted: 1986-07-15
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Expires: 2005-03-06
Abstract
Abstract For use in an automobile bumper, a core material composed of a molded article of prefoamed polyolefin resin particles. The core material has a density of 0.05 to 0.15 g/cm3 and the relation represented by the following expression E20/ rho >/=20 kg-cm/g wherein E20 is the amount of energy absorption (kg-cm/cm3) when the core material is compressed to 50% at 20 DEG C., and rho is the density (g/cm3) of the core material.
Inventors
- 👤 Shohei Yoshimura
- 👤 Akira Adachi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:12
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/22; C08J9/228; C08J9/232; B; B60; B60R; B60R19/00; B60R19/02; B60R19/03; C08J9/16; C08J9/18; C08J2323/00; C08J2323/02; Y; Y10; Y10T; Y10T428/00; Y10T428/23; Y10T428/233; Y10T428/239; Y10T428/249921; Y10T428/249953
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
122 words
A core material for use in automobile bumpers, said core material being composed of a molded article of prefoamed particles of a polyolefin resin, and having a density of 0.05 to 0.15 g/cm 3 and the relation represented by the following expression E.sub.20 /ρ≧20 kg-cm/g wherein E 20 is the amount of energy absorption (kg-cm/cm 3 ) when the core material is compressed to 50% at 20° C., and ρ is the density (g/cm 3 ) of the core material, wherein said particles are nearly spherical in shape, have a particle diameter of 2 to 15 mm, a cell diameter of 0.10 to 2.00 mm and a proportion of closed cells of at least 90% and contain air filled within the cells.
Claim 2
Dependent Claim
122 words
A core material for use in automobile bumpers, said core material being composed of a molded article of prefoamed particles of a polyolefin resin, and having a density of 0.05 to 0.15 g/cm 3 and the relation represented by the following expression E.sub.20 /ρ≧20 kg-cm/g wherein E 20 is the amount of energy absorption (kg-cm/cm 3 ) when the core material is compressed to 50% at 20° C., and ρ is the density (g/cm 3 ) of the core material, wherein said particles are nearly spherical in shape, have a particle diameter of 2 to 15 mm, a cell diameter of 0.10 to 2.00 mm and a proportion of closed cells of at least 90% and contain air filled within the cells.
Claim 3
Dependent Claim
28 words
The core material of claim 1 which has a density of 0.06 to 0.13 g/cm 3 and the relation represented by the following expression E 20 /ρ≧22 kg-cm/g.
Claim 4
Dependent Claim
133 words
In an automobile bumper which is composed of a core material and a surface covering material, the improvement wherein said core material is composed of a molded article of prefoamed particles of a polyolefin resin, and having a density of 0.05 to 0.15 g/cm 3 and the relation represented by the following expression E.sub.20 /ρ≧20 kg-cm/g wherein E 20 is the amount of energy absorption (kg-cm/cm 3 ) when the core material is compressed to 50% at 20° C., and ρ is the density (g/cm 3 ) of the core material, wherein said particles are nearly spherical in shape, have a particle diameter of 2 to 15 mm, a cell diameter of 0.10 to 2.00 mm and a proportion of closed cells of at least 90% and contain air filled within the cells.
Claim 5
Dependent Claim
133 words
In an automobile bumper which is composed of a core material and a surface covering material, the improvement wherein said core material is composed of a molded article of prefoamed particles of a polyolefin resin, and having a density of 0.05 to 0.15 g/cm 3 and the relation represented by the following expression E.sub.20 /ρ≧20 kg-cm/g wherein E 20 is the amount of energy absorption (kg-cm/cm 3 ) when the core material is compressed to 50% at 20° C., and ρ is the density (g/cm 3 ) of the core material, wherein said particles are nearly spherical in shape, have a particle diameter of 2 to 15 mm, a cell diameter of 0.10 to 2.00 mm and a proportion of closed cells of at least 90% and contain air filled within the cells.
Claim 6
Dependent Claim
30 words
The automobile bumper of claim 3 wherein the core material has a density of 0.06 to 0.13 g/cm 3 and the relation represented by the following expression E.sub.20 /ρ≧22 kg-cm/g.
Claim 7
Dependent Claim
17 words
The automobile bumper of claim 3 which has a bumper height of from 50 to 100 millimeters.
Claim 8
Dependent Claim
24 words
The automobile bumper of claim 3 wherein the polyolefin resin is selected from the group consisting of polypropylene, ethylene/propylene random copolymer and high-density polyethylene.
Claim 9
Dependent Claim
15 words
The automobile bumper of claim 3 wherein the polyolefin resin is an ethylene/propylene random copolymer.
Claim 10
Dependent Claim
13 words
The automobile bumper of claim 3 wherein the polyolefin resin is high-density polyethylene.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-07-14 | 1990-01-13 | 1990-07-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-07-14 | 1994-01-13 | 1994-07-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-07-14 | 1998-01-13 | 1998-07-15 | $7700.00 | Window Closed / Lapsed |