Porous sintered metal and nonporous friction material for clutches
First Claim
1. A lubricated friction clutch for a transmission of the synchronization ring and matching cone type,comprising a first clutch part and a second clutch part that can controllably engage one another, forming a friction pairing, in which the first and second clutch parts are made from differing materials the first clutch part having a first friction surface and the second clutch part having a second friction surface, the first and second friction surfaces being opposed to one another, wherein the first friction surface is a specific frictional material having desirable frictional properties, and the second friction surface is made from an iron-based material of high mechanical strength, the first friction surface being substantially non-porous, and the opposing second friction surface is made from microporous sintered material that is considerably harder than the specific frictional material used in the first friction surface, the second friction surface having pores and being microporous, the second friction surface having a friction-effective area A of 50%<
- A<
90% of the portion of the geometrical area of the friction surface giving an effective contribution to friction and having pores with a mean diameter of less than 300 μ
m.
1 Assignment
0 Petitions
Accused Products
Abstract
An automotive transmission lubricated friction clutch is provided having a synchronization ring and matching cone; these parts form a friction pairing. Materials having different friction characteristics and friction wear resistances are used for the friction surfaces forming the friction pairing. A specific friction material is provided having desirable friction characteristics but lacking pores or drainage thread for one friction surface, and a microporous sintered material having a friction-effective area A of 50% <A <90% of the total friction surface and pores with a mean diameter of <300 μm for the other friction surface. Either the synchronization ring or the matching cone are designed to represent one or the other form of friction surface, as desired. Lubricated friction clutches for automotive transmissions can be manufactured according to the invention that have increased life expectancy, shorter shifting times, smaller sizes and reduced manufacturing costs as compared to other clutches.
21 Citations
14 Claims
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1. A lubricated friction clutch for a transmission of the synchronization ring and matching cone type,
comprising a first clutch part and a second clutch part that can controllably engage one another, forming a friction pairing, in which the first and second clutch parts are made from differing materials the first clutch part having a first friction surface and the second clutch part having a second friction surface, the first and second friction surfaces being opposed to one another, wherein the first friction surface is a specific frictional material having desirable frictional properties, and the second friction surface is made from an iron-based material of high mechanical strength, the first friction surface being substantially non-porous, and the opposing second friction surface is made from microporous sintered material that is considerably harder than the specific frictional material used in the first friction surface, the second friction surface having pores and being microporous, the second friction surface having a friction-effective area A of 50%< - A<
90% of the portion of the geometrical area of the friction surface giving an effective contribution to friction and having pores with a mean diameter of less than 300 μ
m. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
- A<
Specification