Electro-rheological fluid and cylinder device using same
AssigneeHitachi Astemo, Ltd.
InventorsSatoshi ISHII, Seogchul SHIN, Yuichiro YAMAMOTO, Hitomi TAKAHASHI
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Abstract
Provided is an electro-rheological fluid, including: a fluid having an insulating property; and a polyether-based polyurethane particle containing a metal ion, wherein the polyurethane particle contains a chain extender, wherein the metal ion includes at least a Li ion, and wherein a ratio ([Li]/[O]) of a molar concentration ([Li]) of the Li ion to a molar concentration ([O]) of oxygen atoms of ether groups in the polyurethane particles satisfies the following condition: [Ratio of molar concentration ([Li]) of Li ion to molar concentration ([O]) of oxygen of ether groups] [Li]/[O]≥9.0×10−5.
Claims15
An electro-rheological fluid, comprising:
- a fluid having an insulating property;
- and
- a polyether-based polyurethane particle comprising a metal ion,
- wherein the polyurethane particle comprises a chain extender,
- wherein the metal ion comprises at least a Li ion, and
- wherein a ratio ([Li]/[O]) of a molar concentration ([Li]) of the Li ion to a molar concentration ([O]) of oxygen atoms of ether groups in the polyurethane particle satisfies the following condition.
- [Ratio of molar concentration ([Li]) of Li ion to molar concentration ([O]) of oxygen of ether groups]
- [
- Li
- ]
-
- /
- [
- O
- ]
- ≥
- 9
- .
- 0
- ×
- 1
-
- 0
- -
- 5
A cylinder device, comprising:
- a piston rod;
- an inner cylinder into which the piston rod is inserted;
- and
- an electro-rheological fluid arranged between the piston rod and the inner cylinder,
- wherein the electro-rheological fluid comprises a fluid having an insulating property and a polyether-based polyurethane particle comprising a metal ion, the polyurethane particle comprises a chain extender, and the metal ion comprises at least a Li ion, and
- wherein a change in damping force of the electro-rheological fluid due to a temperature change is less than 10%.
Dependencies are inferred from the claim text.