Clutch system and vehicle transmission system including the same

Abstract

To provide a clutch system including a first clutch member and a second clutch member for transmitting torque from a vehicle power generator.SOLUTION: A first clutch member has a first clutch element having a first surface, and a first friction material disposed on the first surface. The second clutch member is configured to engage the first clutch plate, and includes a second clutch element having a second surface and a second friction material disposed on the second surface. The first friction material is configured to be engaged with the second friction material during operation of a vehicle power generator.SELECTED DRAWING: Figure 2A

Description

[Technical Field]

[0001] 1.Technical Field

[0002] The present invention relates generally to clutch systems, and more particularly to clutch systems for use in vehicle transmission systems. [Background technology]

[0003] 2. Description of Related Technology

[0004] Several components of a vehicle powertrain may employ systems that facilitate the transfer of power from the vehicle's power generator (i.e., internal combustion engine, electric motor, fuel cell, etc.) to the vehicle's drive wheels. A vehicle transmission is located downstream from the power generator and enables vehicle launch, gear shifting, and other torque transfer events. The vehicle transmission may be coupled to a clutch system. Clutch systems of some form can be found throughout the many different types of vehicle transmissions currently available for vehicle operation. Clutch systems can be used in torque converters for automatic transmissions, multi-plate clutch packs for automatic or semi-automatic dual clutch transmissions (DCTs), and launch clutches that may be incorporated into automatic transmissions with 7 to 10 gears as a replacement for torque converters, to name just a few. Similar clutch systems are found in other locations in the vehicle powertrain besides the vehicle transmission.

[0005] 1 , a conventional clutch system 100 typically includes a plurality of clutch plates 102 rotatably coupled to a shaft 26, the plurality of clutch plates 102 being used to mesh two or more opposing rotating surfaces by selectively creating interfacial frictional engagement between the surfaces. Each clutch plate 102 includes a core plate 104 made of steel and defining a bore for receiving the shaft 26 such that each clutch plate 102 is rotatably coupled to the shaft 26. Each clutch plate 102 additionally includes friction material 108 disposed on either side of the core plate 104, which provides the intended frictional engagement between the plurality of clutch plates 102.

[0006] A conventional clutch assembly 100, as shown in FIG. 1, also includes at least one separator plate 110, typically made of steel, positioned between two consecutive conventional clutch plates 102. During operation, the clutch plates 102 move between an engaged position in which the clutch plates 102 engage with the separator plate 110 and a disengaged position in which the clutch plates 102 disengage from the separator plate 110. The separator plate 110 functions as a heat sink to absorb energy generated by the frictional engagement of the two opposing rotating surfaces. Having a separator plate 110 in the clutch system 100 requires a large axial space of the clutch system 100, and the clutch must be designed for high maximum heat, so a heat sink is not always utilized. Other clutch assemblies include core plates made of steel and with friction material positioned on only one side of the core plate. However, in this arrangement, the friction material of the first clutch plate engages the core plate of the second clutch plate, resulting in potential thermal gradients and additional energy problems. Summary of the Invention [Problem to be solved by the invention]

[0007] Thus, there remains a need to provide an improved clutch system. [Means for solving the problem]

[0008] A clutch system operably coupled to a vehicle power generator is disclosed. The clutch system includes a first clutch member for transmitting torque from the vehicle power generator. The first clutch member includes a first clutch element having a first surface and a first friction material disposed on the first surface. The clutch system also includes a second clutch member for transmitting torque from the vehicle power generator and configured to engage with the first clutch member. The second clutch member includes a second clutch element having a second surface and a second friction material disposed on the second surface. The first friction material and the second friction material may be the same or different. The first friction material is configured to be engaged with the second friction material during operation of the vehicle power generator. A vehicle transmission system including a vehicle transmission and a clutch system is also disclosed. [Effects of the Invention]

[0009] Thus, configuring the first friction material to be engaged with the second friction material during operation of the vehicle engine leads to a reduction in the axial length of the clutch system and also leads to improved performance of the clutch system, more specifically, an increased separation coefficient across a range of loads. [Brief explanation of the drawings]

[0010] Other advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings. [Figure 1] 1 is a simplified cross-sectional view of a prior art clutch system including a plurality of clutch plates and a separator plate; [Figure 2A]1 is a simplified cross-sectional view of a vehicle transmission system according to the present invention including a plurality of clutch plates having a single layer of friction material disposed thereon in a disengaged position. [Figure 2B] 1 is a simplified cross-sectional view of a vehicle transmission system according to the present invention including a plurality of clutch plates having a single layer of friction material disposed thereon in an engaged position. [Figure 3] 3 is a top view of a core plate of the clutch plate according to the embodiment shown in FIG. 2. [Figure 4] FIG. 3 is a top view of a clutch plate according to the embodiment shown in FIG. 2. [Figure 5] 2 is a further simplified cross-sectional view of a clutch system according to the present invention including a plurality of clutch plates having a dual layer friction material disposed thereon. [Figure 6] 2 is a further simplified cross-sectional view of a clutch system according to the present invention including a plurality of clutch plates having a three-layer friction material disposed thereon. [Figure 7] 1 is a graphical representation of instantaneous peak coefficient plotted with respect to friction material load. [Figure 8] 1 is a graphical representation of peel coefficient plotted with respect to friction material load. [Figure 9] FIG. 10 is a side perspective view of a clutch system according to another embodiment in a disengaged position. [Figure 10] FIG. 10 is a side perspective view of the clutch system of FIG. 9 in an engaged position. DETAILED DESCRIPTION OF THE INVENTION

[0011] Referring to the drawings, wherein like numerals indicate like parts throughout the several views, a vehicle transmission system 10 is shown generally in FIG. 2. The vehicle transmission system 10 is operably coupled to a vehicle power generator 12. In one example, the vehicle power generator 12 is a vehicle engine, such as an internal combustion engine, although it is contemplated that the vehicle power generator 12 may be any type of power generator, including, but not limited to, an electric motor, a battery, or a fuel cell. The vehicle transmission system 10 includes a vehicle transmission 14 coupled to the vehicle power generator 12. The vehicle transmission 14 may be any type of transmission, including, but not limited to, automatic, manual, automated-manual, dual-clutch, continuously variable, etc. Additionally, the vehicle transmission system 10 also includes a clutch system 20 operably coupled to the vehicle transmission 14. The clutch system 20 may be a wet clutch system, a semi-wet clutch system, or a dry latch system. It is also contemplated that the clutch system may be a plate clutch system (see FIGS. 2-6), a cone clutch system (see FIGS. 9 and 10), or other clutch system. The clutch system 20 may also include a shaft 26 having a length and an axis A extending along the length.

[0012] In one example, clutch system 20 includes first and second clutch members 21, 23 for transferring torque from vehicle power generator 12. It is contemplated that first and second clutch members 21, 23 may be clutch plates, with first clutch member 21 being first clutch plate 22 and second clutch member 23 being second clutch plate 24. However, it is also contemplated that first and second clutch members 21, 23 may be other clutch members, including, but not limited to, first and second cones 25, 27, respectively. First clutch member 21 also includes first clutch element 29 having first surface 31, and second clutch member 23 includes second clutch element 33 having second surface 35.

[0013] 2A-3 , the first clutch element 29 is a first core plate 28, and the second clutch element 33 is a second core plate 46, although the first clutch element 29 and the second clutch element 33 may be other clutch elements known to those skilled in the art. The first core plate 28 defines a bore 30 extending along an axis A. The bore 30 receives the shaft 26 such that the first core plate 28 is rotatably coupled to the shaft 26. The shaft 26 is also commonly referred to as a hub. The first core plate 28 includes an inner core surface 32 defining the bore 30 and an outer core surface 34 radially spaced apart from the inner core surface 32 relative to the axis A, such that the outer core surface 34 surrounds the inner core surface 32 about the axis A. The first core plate 28 also includes a first side surface 36 extending between the inner core surface 32 and the outer core surface 34 and facing a first direction along the axis A. First core plate 28 further includes a second side 38 extending between inner core surface 32 and outer core surface 34 and facing a second direction opposite the first direction along axis A. Still referring to Figures 2A-3, first core plate 28 is solid between inner core surface 32 and outer core surface 34 around the entire periphery of core plate 28 between inner core surface 32 and outer core surface 34, i.e., core plate 28 is not hollow.

[0014] 3, the first core plate 28 is non-flexible and includes a splined portion 40. In the example shown in FIG. 3, the splined portion 40 includes an outer core surface 34 that includes a plurality of teeth 42 configured to engage with a toothed portion of another component. However, it is contemplated that the splined portion 40 may alternatively include the inner core surface 32 of the core plate 28 such that the plurality of teeth 42 are disposed on the inner core surface 32.

[0015] 2A and 2B, the clutch system 20 includes a second clutch plate 24. The second clutch plate 24 may be the same as or different from the first clutch plate 22. In one example, the second clutch plate 24 includes a second core plate 46 that is similar to the first core plate 28 in that the second core plate 46 also defines a bore for receiving the shaft 26 such that the second core plate 46 is also coupled to the shaft 26. Furthermore, the second core plate 46 also includes a first side surface 50 and a second side surface 52, similar to the first clutch side surface 36 and the second clutch side surface 38 of the first core plate 28 described above. The second core plate 46 may be the same as or different from the first core plate 28 in terms of shape, size, materials of construction, etc.

[0016] The first core plate 28 and the second core plate 46 may be constructed of any suitable material for use in the clutch system 20. At least one of the first core plate 28 and the second core plate 46 is constructed of a metallic material. Such metallic materials that may be used include, but are not limited to, stainless steel, mild carbon steel, and aluminum, and may include surface treatments such as phosphate coating, nickel coating, and anodizing. In one example, at least one of the first core plate 28 and the second core plate 46 is constructed of 1035 carbon steel. As another example, at least one of the first core plate 28 and the second core plate 46 may be constructed of a polymeric material. Examples of such polymeric materials that may be used include thermosetting and thermoplastic materials. Examples of such thermosetting materials that may be used include polyester, vinyl ester, epoxy, phenolic, urethane, polyamide, polyimide, and the like. Examples of such thermoplastic materials that may be used include polyethylene terephthalate (PET), polypropylene, polycarbonate, polybutylene terephthalate (PBT), vinyl, polyethylene, polyvinyl chloride (PVC), and the like. When a polymeric material is used, it may be used as a homogeneous polymeric material or may be used with a polymeric material reinforcement such as metal, fiberglass, carbon fiber, or the like.

[0017] 2A, 2B, and 4, the first clutch plate 22 includes friction material disposed on at least one of the first and second sides 36, 38 of the first core plate 28. The friction material is adhered to the first core plate 28 to form the first clutch plate 22. The friction material may be adhered to the first core plate 28 by, for example, an adhesive. Typically, the first clutch plate 22 includes friction material on both the first and second sides 36, 38. However, it should be understood that the first clutch plate 22 may have friction material on only one of the first side 36 or the second side 38. In the example shown in FIGS. 2A and 2B, the first friction material 54 is disposed on the first side 36 of the first core plate 28, and the second friction material 56 is disposed on the second side 38 of the first core plate 28. Additionally, a third friction material 58 is disposed on the first side 50 of the second core plate 46 and a fourth friction material 60 is disposed on the second side 52 of the second core plate 46 .

[0018] In one example shown in Figures 9 and 10, the first clutch element 29 is a first cone 25, the first surface 31 is an outer conical surface, and the first friction material 54 is disposed on the outer conical surface. In other words, the first cone 25 is a male conical element having an aperture therethrough to receive the shaft 26. The second clutch element 33 is a second cone 27, the second surface 35 is an inner conical surface, whereby the second friction material 56 is disposed on the inner conical surface. In other words, the second cone 27 is a female conical element also having an aperture therethrough to receive the shaft 26 and is configured to be engaged with the first cone 25. The first cone 25 and the second cone 27 can be similar in material, function, bore, etc. to the first and second core plates 28, 46 described herein.

[0019] The first friction material 54, the second friction material 56, the third friction material 58, and the fourth friction material 60 may be the same or different, including having the same or different chemical compositions and / or physical forms. In one example, at least one of the first friction material 54, the second friction material 56, the third friction material 58, and the fourth friction material 60 does not contain steel. Preferably, all of the friction materials 54, 56, 58, and 60 do not contain steel. In other words, it is preferred that none of the first friction material 54, the second friction material 56, the third friction material 58, and the fourth friction material 60 is a separator plate and / or is not composed of steel. In another example, at least one of the first friction material 54, the second friction material 56, the third friction material 58, and the fourth friction material 60 is composed of a paper material. Although not required, in many paper materials, the fibers contained therein contain cotton and have a fiber length of about 1 to about 9 mm. These fibers are described further below. In this paper material example, preferably, all of friction materials 54, 56, 58, and 60 are comprised of paper material. In other words, for this example, it is also preferred that none of first friction material 54, second friction material 56, third friction material 58, and fourth friction material 60 are separator plates and / or comprise steel. As a result of the arrangement described in this paragraph, a friction-to-friction interface is achieved between first clutch plates 22, 24.

[0020] The friction material is a component of the clutch system 20, and any discussion of the friction material contained herein is applicable to any one or more of the first friction material 54, the second friction material 56, the third friction material 58, and the fourth friction material 60. In certain embodiments, the friction material may contain one or more plies or layers. In other words, in this case, the friction material does not include two or more separate plies or layers. In such cases, the friction material may also be referred to as a unitary body.

[0021] In other embodiments, the friction material contains more than one ply or layer, i.e., multiple plies or layers. For example, the friction material may contain two layers, as would be present in a two-ply structure. Non-limiting, exemplary multi-layer friction materials are described in U.S. Patent No. 6,875,711; U.S. Patent No. 10,436,272; and U.S. Patent Publication No. 2019 / 0003544, the entire contents of which are incorporated herein by reference.

[0022] 5, at least one of the first friction material 54, the second friction material 56, the third friction material 58, and the fourth friction material 60 is a two-ply friction material. However, it is contemplated that at least one of the first friction material 54, the second friction material 56, the third friction material 58, and the fourth friction material 60 may be a single-ply friction material as shown in Figures 2A and 2B or a three-ply friction material as shown in Figure 6. It should be understood that a two-ply friction material may be used in combination with a three-ply friction material, if desired.

[0023] As noted above, the first friction material 54, the second friction material 56, the third friction material 58, and the fourth friction material 60 can be the same or different. Although not required, in certain embodiments, the first friction material 54, the second friction material 56, the third friction material 58, and the fourth friction material 60 each independently comprise a friction-generating layer and a base layer. The friction-generating layer provides a friction-generating surface and contains friction particles, including diatomaceous earth particles and / or cashew nut particles. The base layer is adjacent to the friction-generating layer and provides a mating surface facing opposite and generally parallel to the friction-generating surface of the friction-generating layer. The mating surface of the base layer is bonded to the core plates 28, 46, the first cone 25, and the second cone 27. The base layer contains fibers and a filler. As described further below, the fibers of the base layer contain aramid fibers, carbon fibers, and / or cellulose fibers. The filler contains carbon particles and / or diatomaceous earth particles. Additional descriptions and options for fibers and fillers are provided below: Additionally, the friction material is typically porous and includes a resin present in the friction-generating layer and the base material layer.

[0024] The friction material includes a base layer. As noted above, it should be understood that in some embodiments, the friction material is a single-layer material and therefore includes only the base layer and no additional layers (e.g., friction-generating layers). The base layer can alternatively be described as a core layer, a primary layer, or a porous layer. In some embodiments, the base layer has a thickness of 0.2 mm to 3.7 mm, 0.3 mm to 3 mm, 0.3 mm to 2 mm, 0.3 mm to 1 mm, 0.3 mm to 0.9 mm, 0.4 mm to 0.8 mm, 0.5 mm to 0.7 mm, 0.6 mm to 0.7 mm, or 0.2 mm to 0.35 mm. Alternatively, the thickness of the base layer is less than 3.75 mm, less than 3 mm, less than 2 mm, less than 1 mm, less than 0.9 mm, less than 0.8 mm, less than 0.7 mm, less than 0.6 mm, less than 0.5 mm, or less than 0.4 mm, but greater than 0.1 mm. In additional non-limiting embodiments, all thickness values ​​and ranges of values ​​between and including the endpoints of the recited ranges are expressly contemplated by this specification. The thickness may refer to the thickness of the resin before or after curing.

[0025] The substrate layer contains fibers. The fibers may alternatively be described as a plurality of fibers. One or more different types of fibers may be included in the substrate layer. The fibers may be selected from aramid fibers, carbon fibers, cellulose fibers, acrylic fibers, polycarbonate fibers, glass fibers, mineral fibers, and combinations thereof. In various embodiments, the filler comprises one or a combination of the aforementioned filler types. All weight ranges and ratios of various combinations of the aforementioned fibers are expressly contemplated by this specification in various non-limiting embodiments.

[0026] The fibers may include aramid, such as AB homopolymer, AABB polymer, etc. In other embodiments, the fibers consist of or consist essentially of aramid. Various non-limiting examples of aramids include trade names such as Kevlar®, Twaron®, Nomex®, NewStar®, and Teijinconex®. One or more types of aramids may be used. In one embodiment, the aramid is polyparaphenylene terephthalamide. In another embodiment, the aramid is two or more types of aramid, such as a first polyparaphenylene terephthalamide and a second polyparaphenylene terephthalamide different from the first polyparaphenylene terephthalamide.

[0027] In some embodiments, the fibers include cellulose, e.g., cellulose from wood, cotton, etc. In other embodiments, the fibers consist essentially of or consist of cellulose. The cellulose fibers can be selected from abaca, bagasse, bamboo, coir, cotton, fike, flax, linen, hemp, jute, kapok, kenaf, piña, pine, raffia, ramie, rattan, sisal, wood fibers, and combinations thereof. In some specific embodiments, cellulose fibers derived from wood, such as birch and / or eucalyptus, are used. In other embodiments, cellulose fibers such as cotton are used. When used, cotton fibers typically have fibrillated strands attached to the main fiber core to help prevent delamination of the friction material during use.

[0028] In yet other embodiments, the fibers comprise acrylic. In other embodiments, the fibers consist of or consist essentially of acrylic. Acrylic fibers are typically formed from one or more synthetic acrylic polymers, such as those formed from at least 85% by weight of acrylonitrile monomers.

[0029] In yet other embodiments, the fibers comprise carbon. In other embodiments, the fibers consist of or consist essentially of carbon.

[0030] In various embodiments, the fibers have diameters of 1 μm to 500 μm and lengths of 0.1 mm to 20 mm. In additional non-limiting embodiments, all values ​​and ranges of values ​​for diameter and length inclusive of and between the endpoints of the aforementioned ranges are expressly contemplated hereby.

[0031] The fibers may be woven, nonwoven, sintered, or of any other suitable construction.

[0032] In various embodiments, the fibers have a Canadian Standard Freeness (T 227 om) ("CSF") of greater than 200. In some embodiments, less fibrillated fibers are utilized having a CSF of 250 to 550. In still other embodiments, the fibers have a CSF of 550 to 750 or greater than 750. In additional non-limiting embodiments, all values ​​and ranges of values ​​for CSF within and including the endpoints of the aforementioned ranges are expressly contemplated hereby.

[0033] The term "CSF" denotes that the degree of fibrillation of a fiber can be described as a measure of the fiber's freeness. The CSF test is an empirical test procedure that arbitrarily measures the rate at which 3 grams of fiber drains from a suspension in 1 liter of water. Thus, less fibrillated fibers have a higher freeness or higher rate of drainage of fluid from the friction material than other fibers. Notably, the CSF value can be converted to a Schopper-Riegler value. The CSF can be an average value representing the CSF of all fibers. As such, it should be understood that the CSF of any one particular fiber may fall outside the above ranges, but the average value falls within these ranges.

[0034] The substrate layer also includes a filler. The filler is not limited and may be any known in the art. For example, the filler may be a reinforcing or non-reinforcing filler. The filler may be selected from silica, diatomaceous earth, graphite, carbon, alumina, magnesia, calcium oxide, titania, ceria, zirconia, cordierite, mullite, sillimanite, spodumene, petalite, zircon, silicon carbide, titanium carbide, boron carbide, hafnium carbide, silicon nitride, titanium nitride, titanium boride, and combinations thereof. In various embodiments, the filler is diatomaceous earth. In various embodiments, the filler includes a combination of one or more of the aforementioned filler types. All weight ranges and ratios of various combinations of the aforementioned filler types are expressly contemplated by this specification in various non-limiting embodiments.

[0035] The filler can have a particle size of 0.5 to 80 microns, or 0.5 to 20 microns. In additional non-limiting embodiments, all values ​​and ranges of values ​​of particle size inclusive of and within the endpoints of the recited ranges are expressly contemplated hereby.

[0036] The substrate layer may further include additives known in the art.

[0037] The friction material may also include a friction-generating layer. The friction-generating layer is also commonly referred to as a "deposit" or "deposit layer." The friction-generating layer may be disposed on the friction material in a graded pattern measured from the friction-generating surface toward the interior of the base material layer (toward the bonding surface), with the concentration of the components of the friction-generating layer being greatest at the friction-generating surface.

[0038] In many embodiments, the friction-generating layer has a thickness of 10 μm to 600 μm, 12 μm to 450 μm, 12 μm to 300 μm, 12 μm to 150 μm, or 14 μm to 100 μm. Alternatively, the thickness of the friction-generating layer is less than 150 μm, less than 125 μm, less than 100 μm, or less than 75 μm but greater than 10 μm. In additional non-limiting embodiments, all thickness values ​​and ranges of values ​​inclusive of and within the endpoints of the aforementioned ranges are expressly contemplated hereby. Thickness may refer to the thickness of the friction-generating layer before or after the resin has cured.

[0039] The friction-generating layer may include friction-adjusting particles. The friction-adjusting particles may include one or more different types of particles. The friction-adjusting particles provide a high coefficient of friction to the friction material. The type or types of friction-adjusting particles utilized may vary depending on the friction characteristics desired.

[0040] In various embodiments, the friction modifying particles may be selected from any one or more of the filler particle types (fillers) described above, or the fillers may be selected from any one or more of the friction modifying particle types (friction modifying particles) described below.

[0041] In various embodiments, the friction modifying particles are selected from silica particles, carbon particles, graphite particles, alumina particles, magnesia particles, calcium oxide particles, titania particles, ceria particles, zirconia particles, cordierite particles, mullite particles, sillimanite particles, spodumene particles, petalite particles, zircon particles, silicon carbide particles, titanium carbide particles, boron carbide particles, hafnium carbide particles, silicon nitride particles, titanium nitride particles, titanium boride particles, cashew nut particles, rubber particles, and combinations thereof. In various embodiments, the friction modifying particles comprise one or more combinations of the foregoing particle types. All weight ranges and ratios of various combinations of the foregoing particle types are expressly contemplated by this specification in various non-limiting embodiments.

[0042] In some embodiments, the friction modifying particles comprise at least one particle type selected from cashew nut particles, silica particles, and diatomaceous earth particles, while in other embodiments, the friction modifying particles consist essentially of or consist of various combinations of cashew nut particles, silica particles, and diatomaceous earth particles.

[0043] In some embodiments, the friction modifying particles comprise cashew nut particles. In yet other specific embodiments, the friction modifying particles consist essentially of, or consist of, cashew nut particles. Of course, in some such embodiments, the friction-generating layer consists essentially of, or consists of, cashew nut particles. Those skilled in the art will understand that cashew nut particles are particles formed from cashew nut shell liquid. Cashew nut shell liquid is sometimes referred to as cashew nut shell liquid (CNSL) and its derivatives.

[0044] In some embodiments, the friction modifying particles comprise diatomaceous earth particles. Of course, in other embodiments, the friction modifying particles consist essentially of, or consist of, diatomaceous earth particles. In some such embodiments, the friction-generating layer therefore consists essentially of, or consists of, diatomaceous earth particles. Diatomaceous earth is a silica-containing mineral. Diatomaceous earth is an inexpensive abrasive that exhibits a relatively high coefficient of friction. CELITE® and CELATOM® are two trade names for diatomaceous earth that may be used.

[0045] In some embodiments, the friction modifying particles comprise a combination of cashew nut particles and diatomaceous earth particles. Of course, in other embodiments, the friction modifying particles consist essentially of, or consist of, a combination of cashew nut particles and diatomaceous earth particles. In some such embodiments, the friction-generating layer consists essentially of, or consists of, a combination of cashew nut particles and diatomaceous earth particles.

[0046] In various embodiments, the friction modifying particles comprise elastomer particles. Elastomer particles exhibit elasticity and other rubber-like properties. Such elastomer particles may be at least one particle type selected from cashew nut particles and rubber particles. In some embodiments, rubber particles are used that include silicone rubber, styrene butadiene rubber, butyl rubber, and halogenated rubber (e.g., chlorobutyl rubber, bromobutyl rubber, polychloroprene rubber, nitrile rubber), etc. In other embodiments, rubber particles are used that consist essentially of or consist of silicone rubber, styrene butadiene rubber, butyl rubber, and halogenated rubber (e.g., chlorobutyl rubber, bromobutyl rubber, polychloroprene rubber, nitrile rubber), etc.

[0047] In some particular embodiments, the elastomeric particles comprise silicone rubber particles, hi other particular embodiments, the elastomeric particles consist essentially of or consist of silicone rubber particles.

[0048] In some particular embodiments, the elastomer particles comprise nitrile rubber particles. In other particular embodiments, the elastomer particles consist essentially of or consist of nitrile rubber particles.

[0049] In various embodiments, the friction modifying particles have an average diameter of 100 nm to 80 μm, 500 nm to 30 μm, or 800 nm to 20 μm. In additional non-limiting embodiments, all values ​​and ranges of values ​​of average diameter within and including the endpoints of the recited ranges are expressly contemplated hereby.

[0050] The friction-generating layer may further comprise friction-adjusting fibers, which may be selected from any of the fiber types described above.

[0051] In some embodiments, the friction-generating layer comprises friction modifying particles but does not comprise friction modifying fibers, hi some such embodiments, the friction-generating layer consists essentially of or consists of friction modifying particles.

[0052] In other embodiments, the friction-generating layer includes both friction-modifying particles and friction-modifying fibers. For example, in some particular embodiments, the friction-generating layer includes cellulose fibers, diatomaceous earth particles, and optionally elastomeric particles.

[0053] The friction-generating layer may further include additives known in the art.

[0054] In various embodiments, the components of the friction-generating layer (e.g., friction modifying particles, friction modifying fibers, and / or optional additives) are within the top 3000 ft of the base layer. 2 0.5-100 lbs (278.71 m 2 0.2 to 45.4 kg per 3000 ft of the surface of the substrate layer 2 3 to 80 lbs per 278.71 m² (1.4 kg to 36.3 kg per 278.71 m²) of the surface of the substrate layer 2 3-60 lbs (278.71 m) 2 1.4kg to 27.2kg per unit area) and the surface of the substrate layer 2 3 to 40 lbs per 278.71 m² (1.4 kg to 18.1 kg per 278.71 m²) of the top 3000 ft² of the substrate layer 2 3-20 lbs (278.71 m) 2 1.4 kg to 9.1 kg per 3000 ft² (1.4 kg to 5.4 kg per 278.71 m²) of the surface of the substrate layer, or 3 to 12 lbs per 3000 ft² (1.4 kg to 5.4 kg per 278.71 m²) of the surface of the substrate layer 2 3-9 lbs (278.71 m) 2 The amounts used are 1.4 kg to 4.1 kg per 3000 ft. In additional non-limiting embodiments, all amounts and ranges of values ​​inclusive of and within the endpoints of the ranges set forth above are expressly contemplated hereby. 2The unit is lbs per 3000 ft² of the surface of the substrate layer, a unit commonly used in the paper industry as a measure of weight based on surface area. 2 This represents the weight of the friction-generating layer per unit area.

[0055] As indicated above, the friction material may also include one or more additional layers, which may include any combination of the fibers and fillers described above.

[0056] The resin is present within the friction material. The resin can be uniformly or non-uniformly dispersed within the friction material. In some embodiments, the resin is present in one of the layers. Typically, the resin is present in all of the one or more layers.

[0057] The resin is curable. Alternatively, the resin can be of the non-curable variety. In various embodiments, depending on the stage of formation of the friction material, the resin can be uncured, partially cured, or fully cured.

[0058] In some embodiments, the resin may be any thermosetting resin suitable for providing structural strength to the friction material. Phenolic resins and phenol-based resins may be used. Phenolic resins are a type of thermosetting resin produced by the condensation of an aromatic alcohol, typically phenol, with an aldehyde, typically formaldehyde. Phenolic resins are thermosetting resin blends that typically contain at least 50% phenolic resin by weight, based on the total weight of all resins, excluding any solvents or processing acids. It should be understood that various phenolic resins may contain modifying components such as epoxy, butadiene, silicone, tung oil, benzene, cashew oil, and the like. In some embodiments, silicone-modified phenolic resins are used that contain 5 to 80% by weight of a silicone resin, with the remainder being attributable to the phenolic resin or a combination of the phenolic resin with other different resins. In other embodiments, epoxy-modified phenolic resins are used that contain 5 to 80% by weight of an epoxy resin, with the remainder being attributable to the phenolic resin or a combination of the phenolic resin with other different resins.

[0059] In some embodiments, the resin comprises 5 to 100 or 5 to 80 weight percent silicone resin, based on the total weight of all resins, excluding any solvents or processing acids. Silicone resins that can be used include thermoset silicones and elastomeric silicones. Various silicone resins, such as those containing D, T, M, and Q units (e.g., DT resins, MQ resins, MDT resins, MTQ resins, QDT resins, etc.), can also be used.

[0060] In various embodiments, the resin is present in an amount of 20-90, 20-80, or 25-60 weight percent, based on the total weight of all non-resin components in the friction material 10. For example, the resin may be present in an amount of 25-75, 25-70, 30-75, 30-70, 30-55, or 35-65 weight percent, based on the total weight of all non-resin components in the friction material. This value may alternatively be described as the "target pick-up" of the resin. In additional non-limiting embodiments, all values ​​and ranges of values ​​for resin amount within and including the endpoints of the aforementioned ranges are expressly contemplated hereby.

[0061] Once cured, the cured resin provides strength and rigidity to the friction material, adheres the components of the layer(s) to one another while maintaining a desired porosity for proper lubricant flow and retention, and bonds the friction material to a substrate (e.g., core plates 28, 46), as described below.

[0062] The friction material includes a plurality of pores, the pores having a uniform pore size.

[0063] The pores can be uniformly or non-uniformly distributed throughout the friction material. For example, at least one of the base layer, the friction-generating layer, and any additional layers can contain pores (be porous). In some examples, each layer has a different porosity, average pore size, and / or median pore size. In other examples, each layer has approximately the same porosity, average pore size, and / or median pore size.

[0064] Pore ​​size can be determined using ASTM D4404-10. In various embodiments, the friction material has a median pore size of 0.5 to 50, 1 to 50, 2 to 50, 2 to 45, 2 to 30, 2 to 15, or 3 to 10 μm, as determined using ASTM D4404-10. In additional non-limiting embodiments, all values ​​and ranges of values ​​of median pore size inclusive of and within the endpoints of the aforementioned ranges are expressly contemplated hereby.

[0065] In other embodiments, the friction material has a void volume of 25% to 85% as determined using ASTM D4404-10. The void volume of a friction material may be described as the percentage of the friction material that is open to air. In various embodiments, the friction material 10 has a void volume of 30 to 80%, or 40 to 75%, as determined using ASTM test method D4404-10. In additional non-limiting embodiments, all values ​​and ranges of values ​​of void volume within and including the endpoints of the aforementioned ranges are expressly contemplated by this specification.

[0066] In still other embodiments, the friction material has a compression of 2 to 30, 4 to 15, or 6 to 8% at 2 MPa. Compression is a material property of a friction material that can be measured when the friction material is disposed on a substrate (i.e., when the friction material is disposed on a core plate as part of a friction plate) or when the friction material is not disposed on a substrate. Typically, compression is a measurement of the distance (e.g., mm) that the friction material 10 is compressed under a specific load. For example, the thickness of the friction material 10 is measured before a load is applied. Then, the load is applied to the friction material 10. The new thickness of the friction material 10 after the load has been applied for a specified time is measured. Notably, this new thickness of the friction material 10 is measured while the friction material 10 is still under load. As will be appreciated by those skilled in the art, compression is typically related to elasticity. The more elastic the friction material, the more rebound is observed after compression. This typically leads to less lining loss and less hot spot formation, both of which are desirable during use. In additional non-limiting embodiments, all values ​​and ranges of values ​​of compression within and including the endpoints of the stated ranges are expressly contemplated by this specification.

[0067] The initial thickness of the friction material is typically 0.3 to 4, 0.4 to 3, 0.4 to 2, 0.4 to 1.6, 0.4 to 1.5, 0.5 to 1.4, 0.6 to 1.3, 0.7 to 1.2, 0.8 to 1.1, or 0.9 to 1 mm. This thickness refers to the thickness before bonding to a substrate (e.g., core plate 28, 46) and may be referred to as the caliper thickness. This thickness may refer to the thickness of the friction material with uncured resin dispersed throughout or the thickness of the base paper without any resin present. In additional non-limiting embodiments, all thickness values ​​and ranges of values ​​inclusive of and within the endpoints of the aforementioned ranges are expressly contemplated by this specification.

[0068] After bonding to the substrate and the resin has cured, the friction material typically has a total thickness of 0.3 to 3.75, 0.4 to 3, 0.4 to 2, 0.4 to 1.6, 0.4 to 1.5, 0.5 to 1.4, 0.6 to 1.3, 0.7 to 1.2, 0.8 to 1.1, or 0.9 to 1 mm. This thickness is typically the thickness of the fiber / substrate, including deposits and resin, measured after bonding to the substrate. In additional non-limiting embodiments, all values ​​and ranges of values ​​for total thickness inclusive of and within the endpoints of the aforementioned ranges are expressly contemplated hereby.

[0069] In various embodiments, the friction material is bonded to a substrate, typically a core plate, a first cone, and a second cone, and when bonded to the substrate, the bonding surfaces achieve a bonded attachment to the substrate with or without the aid of an adhesive or some other suitable bonding technique.

[0070] In one example, the friction material includes a friction-generating layer that provides a friction-generating surface. The friction-generating material includes friction-modifying particles selected from carbon particles, diatomaceous earth particles, cashew nut particles, and combinations thereof. The friction material may include a base layer adjacent to the friction-generating layer, providing a mating surface opposite the friction-generating surface of the friction-generating layer. The base layer includes fibers, including aramid fibers, carbon fibers, and / or cellulose fibers, along with a filler containing carbon particles and / or diatomaceous earth particles. Resin is present in the friction-generating layer, core layer, and base layer.

[0071] During operation of the vehicle power generator 12, the first clutch plate 22 and the second clutch plate 24 move between a disengaged position, in which the first clutch plate 22 and the second clutch plate 24 are disengaged from one another, and an engaged position, in which the clutch plate 22 and the second clutch plate 24 are engaged with one another. Conventional clutch systems 110 (see FIG. 1 ) include steel separator plates positioned between the clutch plates to provide a heat sink for energy generated during engagement. Importantly, however, the clutch system 20 described herein does not include a steel separator plate. More specifically, when the first clutch plate 22 and the second clutch plate 24 are in the engaged position, the second friction material 56 disposed on the first core plate 28 is configured to engage with the third friction material 58 disposed on the second core plate 46. The direct engagement of the second friction material 56 and the third friction material 58 establishes a friction-to-friction interface. Furthermore, by directly engaging the second friction material 56 and the third friction material 58, the separation coefficients at "Instantaneous Peak" (FIG. 7) and at "1 second" (FIG. 8) are increased over conventional clutch assemblies having steel separator plates. More specifically, FIGS. 7 and 8 graphically illustrate the increased separation coefficients and instantaneous peaks of the first and second improved clutch systems 20 (either improved clutch system 1 or 2) compared to conventional clutch systems 1, 2, and 3. Eliminating separator plates leads to reduced weight and axial length of both the vehicle transmission system 10 and the clutch system 20, which leads to increased overall fuel efficiency and reduced vehicle emissions. Furthermore, directly engaging the second friction material 56 and the third friction material 58 with each other during operation leads to additional vehicle performance improvements, including increased separation coefficients across a variety of loads, as best shown in FIGS. 7 and 8.

[0072] Similarly, as best shown in Figures 9 and 10, the first cone 25 and the second cone 27 move between a disengaged position in which the first cone 25 and the second cone 27 are disengaged from one another and an engaged position in which the first cone 25 and the second cone 27 are engaged with one another. That is, the first friction material 54 of the first cone 25 engages the second friction material 56 of the second cone 27. Conventional cone clutch systems engage the first friction material 54 of the first cone 25 with a steel surface of the second cone 27 to provide a heat sink for energy generated during engagement. However, the clutch system 20 described herein engages the first friction material 54 of the first cone 25 with the second friction material 56 of the second cone 27. By directly engaging the first friction material 54 and the second friction material 56, a friction interface is established, which, as previously described, provides reduced weight and length along with improved vehicle performance.

[0073] All combinations of the above embodiments throughout the disclosure are expressly contemplated by this specification in one or more non-limiting embodiments, even if such disclosure is not verbatim set forth in a single paragraph or section above. In other words, an expressly contemplated embodiment may include any one or more elements described above selected and combined from any part of this disclosure. Furthermore, one or more of the above values ​​may be adjusted by, for example, ±5%, ±10%, ±15%, ±20%, ±30%, ±40%, ±50%, ±60%, ±70%, ±80%, ±90%, ±100%, ±120%, ±140%, ±160%, ±180%, ±200%, ±220%, ±240%, ±260%, ±280%, ±300%, ±400%, ±500%, ±500%, ±600%, ±700%, ±800%, ±900%, ±1000%, ±1200%, ±1400%, ±1600%, ±1800%, ±1800%, ±1900%, ±2000%, ±2200%, ±2400%, ±2600%, ±2800%, ±3000%, ±4000%, ±5000%, ±5000%, ±6000%, ±7000%, ±8000%, ±9000%, ±1900%, ±1900%, ±2000%, ±2000%, ±3000%, ±4000%, ±5000%, ±5000%, ±6000%, ±7000%, ±8000%, ±9000%, ±1900%, ±1900%, ±2000%, ±1900%, ±2000%, ±2000%, ±3000%, ±4000%, ±5000%, ±5000%, ±6000%, ±7000%, ±8000%, ±9000%, ±1900%, ± It is acceptable for the results to vary by ±20%, ±25%, etc. Unexpected results may be obtained from each member of a Markush group (or groups) independent of all other members (members). Each member, individually and / or in combination, may be relied upon in specific embodiments within the appended claims and may provide adequate support for such embodiments. The subject matter of all combinations of independent and dependent claims, both singly and multiple dependent, is expressly contemplated herein. The present disclosure is illustrative, including in terms used to describe rather than to limit. Many modifications and variations of the present disclosure are possible in light of the above teachings, and the present disclosure may be practiced in ways other than as specifically described herein.

[0074] In describing various embodiments of the present disclosure, both individually and collectively, any ranges and subranges relied upon should be understood to be included within the scope of the appended claims, and all ranges incorporating all and / or any partial values ​​herein should be understood to be described and contemplated, even if such values ​​are not explicitly set forth herein. Those skilled in the art will readily recognize that the recited ranges and subranges fully describe and enable various embodiments of the present disclosure, and that these ranges and subranges may be further described into related halves, thirds, fourths, fifths, etc. As merely an example, a range of "0.1 to 0.9" may be further described, individually and collectively, into a lower third, i.e., 0.1 to 0.3; a middle third, i.e., 0.4 to 0.6; and an upper third, i.e., 0.7 to 0.9, all of which may be relied upon individually and / or collectively for specific embodiments within the scope of the appended claims to provide appropriate support for such embodiments. Additionally, for expressions defining or modifying ranges, such as "at least," "greater than," "less than," "equal to or less than," etc., it should be understood that such expressions include subranges and / or upper or lower limits. As another example, the range "at least 10" inherently includes subranges of at least 10 to 35, at least 10 to 25, 25 to 35, etc., each of which may be relied upon individually and / or collectively for specific embodiments within the appended claims and provide appropriate support for such embodiments. Finally, individual numbers within a disclosed range may be relied upon for specific embodiments within the appended claims and provide appropriate support for such embodiments. For example, the range "1 to 9" includes various individual integers, such as 3, as well as individual numbers including decimal points (or fractions), such as 4.1, which may be relied upon for specific embodiments within the appended claims and provide appropriate support for such embodiments.

Claims

1. 1. A clutch system operably coupled to a vehicle power generator, said clutch system comprising: a first clutch member for transmitting torque from the vehicle power generator, a first clutch element having a first surface; and a first clutch member comprising a first friction material disposed on the first surface; a second clutch member configured to transfer torque from the vehicle power generator and to engage the first clutch member, a second clutch element having a second surface; and a second clutch member comprising a second friction material disposed on the second surface; The first friction material and the second friction material may be the same or different, and the first friction material is configured to engage the second friction material during operation of the vehicle power generator.

2. The clutch system of claim 1 , wherein at least one of the first clutch element and the second clutch element is made of steel.

3. 3. The clutch system of claim 1, wherein at least one of the first friction material and the second friction material is steel-free.

4. 4. The clutch system of claim 1, wherein at least one of the first friction material and the second friction material comprises a paper material.

5. The clutch system of any one of claims 1 to 4, wherein at least one of the first friction material and the second friction material is a two-ply friction material.

6. 6. The clutch system of claim 1, wherein the first clutch element is a first cone and the first surface is an outer cone surface, whereby the first friction material is disposed on the outer cone surface.

7. 7. The clutch system of claim 6, wherein said second clutch element is a second cone and said second surface is an inner cone surface, whereby said second friction material is disposed on said inner cone surface.

8. 1. A vehicle transmission system operably coupled to a vehicle power generator, comprising: a vehicle transmission coupled to the vehicle power generator; and A vehicle transmission system comprising the clutch system of any one of claims 1 to 7 operably connected to the vehicle transmission.

9. 1. A clutch system operably connected to a vehicle engine, the clutch system comprising: a first clutch plate for transmitting torque from the vehicle engine, a first core plate; a first friction material disposed on a first side of the first core plate; a second friction material disposed on a second side of the first core plate opposite the first side of the first core plate; and a second clutch plate configured to transmit torque from the vehicle engine and to engage the first clutch plate, a second core plate; a third friction material disposed on a first side of the second core plate; and a fourth friction material disposed on a second side of the second core plate opposite the first side of the second core plate; the first friction material, the second friction material, the third friction material, and the fourth friction material may be the same or different; The clutch system, wherein the second friction material is configured to engage the third friction material during operation of the vehicle engine.

10. The clutch system of claim 9 , wherein at least one of the first core plate and the second core plate is made of steel.

11. 11. The clutch system of claim 9, wherein at least one of the first friction material, the second friction material, the third friction material, and the fourth friction material does not include steel.

12. 12. The clutch system of claim 9, wherein at least one of the first friction material, the second friction material, the third friction material, and the fourth friction material is a single layer friction material.

13. 13. The clutch system of any one of claims 9 to 12, wherein the clutch system does not include a steel separator plate.

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