Abstract:
Adapter rings for attaching automotive clutch assemblies to different types of flywheels are disclosed. A single adapter ring may be installed on different types of stock or aftermarket flywheels. In one embodiment, a multiple-disc clutch assembly may be mounted onto the adapter ring. The multiple-disc clutch unit may fit inside a stock bellhousing to enable the user to utilize the stock clutch release mechanism and simultaneously increase the holding power capability while maintaining light pedal effort. Aftermarket replacement OEM clutch units including the adapter ring may be used with higher horsepower engines in automotive vehicles with manual transmissions.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/422,892 filed Dec. 14, 2010, which is incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to adapter rings for attaching automotive clutch assemblies to different types of flywheels. A single adapter ring may be used to mount aftermarket multiple-disc clutch assemblies to various types of automotive flywheels. 
       BACKGROUND INFORMATION 
       [0003]    Automotive clutch assemblies are typically mounted on a flywheel driven by the engine of the automobile. In certain types of clutch assemblies, multiple clutch discs are used in order to increase the frictional surface area when the clutch is engaged. Examples of multiple-disc clutch assemblies are disclosed in U.S. Pat. Nos. 3,360,089; 3,797,622; 4,466,524; 4,540,079; 4,715,484; 4,815,189; 5,054,597; 7,977,991, which are incorporated herein by reference. 
         [0004]    Aftermarket multiple-disc clutch assemblies are often installed in automobiles to increase performance. Original equipment manufacturer (OEM) or stock clutch units may not provide optimum performance and often require replacement because they cannot support the horsepower of the engine, and can fail. Higher horsepower engines and drivelines require a higher performance or heavy duty clutch unit to hold the horsepower for proper application to the driveline. 
         [0005]    Different types of automobiles have different types of flywheels. The mounting arrangement for aftermarket clutch assemblies is different based upon the particular type of automobile and its corresponding flywheel design. In the past, providing a higher performance OEM replacement clutch unit required the user to additionally purchase a matching flywheel. Most aftermarket high performance clutch assemblies are sold with a new or dedicated flywheel, which adds to the cost of upgrading clutch and auto performance. Furthermore, most aftermarket OEM replacement clutches have a harder-than-stock pedal effort, which makes the vehicle more difficult to drive, and the clutch may not release properly with OEM hydraulic release systems. 
         [0006]    The adapter rings of the present invention solve the problems noted above and are able to be used on street or strip driven automotive vehicles. 
       SUMMARY OF THE INVENTION 
       [0007]    The present invention provides adapter rings for attaching automotive clutch assemblies to different types of flywheels. A single adapter ring may be installed on different types of stock or aftermarket flywheels. In one embodiment, a multiple-disc clutch assembly may be mounted onto the adapter ring. The multiple-disc clutch unit may fit inside a stock bellhousing to enable the user to utilize the stock clutch release mechanism and simultaneously increase the holding power capability while maintaining light pedal effort. Aftermarket replacement OEM clutch units with adapter rings of the present invention may be used with higher horsepower engines in manual transmission automotive vehicles for street and strip use. 
         [0008]    An aspect of the present invention is to provide an adapter ring for attaching automotive clutch assemblies to flywheels comprising an annular base having a flywheel-engaging surface, at least one raised portion extending axially from the base structured for attachment to the clutch assembly, a first set of flywheel mounting holes extending axially through the base arranged for mounting the adapter ring to a first type of flywheel, and a second set of flywheel mounting holes at different locations from the first set of flywheel mounting holes extending axially through the base arranged for mounting the adapter ring to a second type of flywheel. 
         [0009]    Another aspect of the present invention is to provide an assembly comprising an automotive clutch assembly, an automotive flywheel, and an adapter ring connecting the automotive clutch assembly to the automotive flywheel, wherein the adapter ring comprises a first set of flywheel mounting holes that are used to mount the adapter ring on the automotive flywheel, and a second set of flywheel mounting holes that are not used to mount the adapter ring on the automotive flywheel. 
         [0010]    A further aspect of the present invention is to provide a method of installing an automotive clutch assembly on an automotive flywheel comprising selecting an adapter ring from a plurality of adapter rings having different flywheel mounting hole arrangements, attaching the automotive clutch assembly to the adapter ring, and attaching the adapter ring to the automotive flywheel. 
         [0011]    These and other aspects of the present invention will be more apparent from the following description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]      FIG. 1  is a partially schematic side sectional view illustrating an automotive flywheel and clutch assembly including an adapter ring in accordance with an embodiment of the present invention. 
           [0013]      FIG. 2  is a plan view of an adapter ring in accordance with an embodiment of the present invention. 
           [0014]      FIG. 3  is a side sectional view taken through section  3 - 3  of  FIG. 2 . 
           [0015]      FIG. 4  is a plan view of an adapter ring in accordance with another embodiment of the present invention. 
           [0016]      FIG. 5  is a side sectional view taken through section  5 - 5  of  FIG. 4 . 
           [0017]      FIG. 6  is a plan view of an adapter ring in accordance with a further embodiment of the present invention. 
           [0018]      FIG. 7  is a side sectional view taken through section  7 - 7  of  FIG. 6 . 
       
    
    
     DETAILED DESCRIPTION 
       [0019]      FIG. 1  is a partially schematic side sectional view illustrating a clutch assembly  5  including a clutch cover  6 . The clutch assembly  5  is mounted on a flywheel  8  driven by an automobile engine (not shown). An adapter ring  10  of the present invention is mounted on the flywheel  8  by bolts or any other conventional type of mechanical fastener. The clutch assembly  5  may be of any known design, including multiple-disc clutch assemblies and the like. Examples of suitable multiple-disc clutch assemblies  5  that may be used with adapter rings of the present invention include assemblies commercially available from McLeod Racing, LLC under the designations McLeod RST Street Twin and McLeod RXT Street Twin. 
         [0020]      FIGS. 2 and 3  illustrate an adapter ring  10  in accordance with an embodiment of the present invention. The adapter ring  10  includes an annular base  11  having a substantially flat surface for contacting a flywheel, and several sets of flywheel mounting holes extending therethrough in an axial direction parallel with the central axis of the adapter ring  10 . 
         [0021]    As shown most clearly in  FIG. 2 , the adapter ring  10  includes a first set of six flywheel mounting holes  12  equally spaced around the circumference of the base  11 , i.e., at intervals of 60°. In the embodiment shown, the diametrical distance between the centers of opposing holes is 12.375 inches. Each hole  12  of the first set may have a diameter of 0.395-0.397 inch. While various dimensions are disclosed herein for purposes of describing certain embodiments of the present invention, it is to be understood that many different modifications may be made to the configurations and dimensions described herein, and such modifications are intended to be within the scope of the present invention. 
         [0022]    The adapter ring  10  includes a second set of six flywheel mounting holes  13  equally spaced around the circumference of the base  11  at different positions from the first set of flywheel mounting holes  12 . In the embodiment shown, the diametrical distance between opposing holes  13  is 12.625 inches, and each hole  13  has a diameter of 0.395-0.397 inch. 
         [0023]    A third set of flywheel mounting holes  14  comprises three pairs of holes, with each pair equally spaced around the circumference of the base  11 , i.e., at intervals of 120°. In each pair of the third set of holes  14 , the adjacent holes are located an arc distance of 32° away from each other, as measured around the circumference of the base  11 . The third set of flywheel mounting holes  14  are located the same radial distance from the center of the adapter ring  10  as the first set of flywheel mounting holes  12 . The diameter of each hole  14  of the third set is 0.315-0.316 inch. 
         [0024]    A fourth set of flywheel mounting holes  15  comprises three pairs of holes spaced equal distances apart around the circumference of the base  11  at different locations from the first, second and third sets of holes  12 ,  13  and  14 . Each pair of holes  15  in the fourth set are located a linear distance of 3.563 inches from each other. The holes  15  of the fourth set have diameters of 0.315-0.316 inch. The holes  15  are located a radial distance from the center of the adapter ring  10  such that a circle extending around the circumference of the adapter ring  10  passing through the center of each hole  15  has a diameter of 12.875 inches. 
         [0025]    As shown most clearly in  FIG. 2 , three recesses  16  are spaced equal distances around the circumference of the base  11 . When mounting conventional clutch assemblies, the recesses  16  provide receiving areas for the heads of rivets (not shown) that hold clutch floater straps to floater plates, and allow clearance when the pressure plates compress the clutch discs and floater assembly. The recesses  16  may thus be used to space the clutch pressure plate to the correct height to properly compress two discs and one floater plate to the flywheel, and to space the drive straps for the floater plate to the correct release height. Spacing the floater straps allows for correct release of the discs. A secondary benefit allows added strength to the entire adapter ring. A circle around the circumference of the base  11  passing through the center of each recess  16  has a diameter of 10.935 inches. Each recess  16  has a diameter of 0.625 inch, and is 0.15 inch deep. 
         [0026]    As shown in  FIGS. 2 and 3 , the adapter ring  10  includes raised portions  17  that extend from the base  11  in an axial direction parallel with the central axis of the adapter ring  10 . In the embodiment shown, the adapter ring has three raised portions  17 . The height H of each raised portion  17 , measured in the axial direction from the surface of the base  11 , may be selected depending upon the amount of compression that is required to apply correct pressure to the clutch disc(s), floater plate(s), and flywheel. In the embodiment shown, the height H is 0.350 inch, and the thickness B of the base  11  is 0.220 inch. The overall thickness T of the adapter ring  10  is 0.570 inch (+0.002/−0.000). As shown in  FIG. 3 , a portion of the raised portion  17  has a slightly increased thickness T′ of 0.590 inch. However, it is to be understood that such dimensions may be modified as desired. 
         [0027]    The base  11  of the adapter ring  10  in the embodiment shown in  FIGS. 2 and 3  has an inside diameter of 10.000 inches, and an outside diameter of 13.500 inches. The raised portions  17  have the same inside diameter as the base  11 , and have an outside diameter of 11.125 inches. However, such dimensions may be modified as desired. 
         [0028]    As shown in  FIG. 2 , six pressure plate mounting holes  18  are located at equally spaced distances around the circumference of the adapter ring  10 , and extend axially through the raised portions  17  and base  11 . The pressure plate mounting holes  18  are tapped for receiving threaded bolts (not shown), e.g., tapped for standard ⅜-16 bolts. A circle around the circumference of the adapter ring  10  passing through the center of each hole  18  has a diameter of 10.550 inches. 
         [0029]    As further shown in  FIG. 2 , three floater strap mounting holes  19  located at equal distances around the circumference of the adapter ring  10  extend axially through the raised portions  17  and the base  11 . The floater strap mounting holes  19  are tapped for receiving threaded bolts (not shown). The floater strap mounting holes  19  are located the same radial distance from the center of the adapter ring  10  as the pressure plate mounting holes  18 . As shown in  FIG. 2 , the linear distance between each floater strap mounting hole  19  and the closest recess  16  is 2.355 inches. 
         [0030]    In accordance with another embodiment of the present invention as illustrated in  FIGS. 4 and 5 , an adapter ring  20  is provided including a base  21  and raised portions  17  similar to those of the adapter ring  10  shown in  FIGS. 2 and 3 . However, the adapter ring  20  shown in  FIGS. 4 and 5  includes different sizes and arrangements of flywheel mounting holes in comparison with the adapter ring  10  shown in  FIGS. 2 and 3 . 
         [0031]    In the embodiment of  FIGS. 4 and 5 , the adapter ring  20  includes a first set of six flywheel mounting holes  22  equally spaced around the circumference of the base  21 . In the embodiment shown, the diametrical distance between opposing flywheel mounting holes  22  is 12.375 inches, and the diameter of each hole  22  is 0.395-0.397 inch. 
         [0032]    The adapter ring  20  includes a second set of six flywheel mounting holes  23  equally spaced around the circumference of the base  21 , at different locations from the first set of holes  22 . The holes  23  are located a diametric distance of 12.625 inches away from each other, and have diameters of 0.395-0.397 inch. 
         [0033]    The adapter ring  20  also includes a first set of three dowel pin holes  24  extending axially through the base  21  that are spaced equally around the circumference of the base, i.e., at 120° intervals. The dowel pin holes  24  may be used to locate the adapter ring  20  on the flywheel and align the mounting holes of the adapter ring  20  to the flywheel. The dowel pin holes  24  are located the same radial distance from the center of the adapter ring  20  as the first set of holes  22 . Each dowel pin hole  24  has a diameter of 0.252-0.253 inch. 
         [0034]    The adapter ring  20  includes a second set of two dowel pin holes  25  extending axially through the base  21  that are equally spaced around the circumference of the base  21 , i.e., at 180° intervals. The dowel pin holes  25  may be used to locate the adapter ring  20  on the flywheel and align the mounting holes of the adapter ring  20  to the flywheel. The diametric distance between the two dowel pin holes  25  is 12.772 inches, and the diameter of each dowel pin hole is 0.241-0.242 inch. 
         [0035]    The adapter ring  20  as shown in  FIGS. 4 and 5  includes the same arrangement of recesses  16 , raised portions  17 , pressure plate mounting holes  18 , and floater strap mounting holes  19  as shown in the embodiment of  FIGS. 2 and 3 . 
         [0036]    As can be seen by comparing the two different embodiments of the adapter rings  10  and  20 , the rings have the same overall dimensions and common mounting hole arrangements for the clutch assemblies. However, the different patterns of flywheel mounting holes allow the adapter ring  10  of  FIGS. 2 and 3  to be used on various types of flywheels, while the adapter ring  20  of  FIGS. 4 and 5  may be used on various other types of flywheels. 
         [0037]    In accordance with a further embodiment of the present invention as shown in  FIGS. 6 and 7 , an adapter ring  30  comprises a base  31  with similar recesses  16 , raised portions  17 , pressure plate mounting holes  18 , and floater strap mounting holes  19  as shown in the embodiments of  FIGS. 2-5 . However, in the embodiment shown in  FIGS. 6 and 7 , the outer diameter of the base  31  is 12.250 inches, which is slightly smaller than the embodiments shown in  FIGS. 2-5 . The smaller outer diameter of the adapter ring  30  and its unique flywheel mounting hole arrangement permits the adapter ring  30  to be used with various types of flywheels different from the flywheels to which the adapter rings  10  and  20  may be mounted. 
         [0038]    As shown in  FIG. 6 , the adapter ring  30  includes a first set of six flywheel mounting holes  32  equally spaced around the circumference of the base  31 . The flywheel mounting holes  32  of the first set are located diametric distances of 11.375 inches from each other. Each hole  32  has a diameter of 0.315-0.316 inch. 
         [0039]    A second set of six flywheel mounting holes  33  are equally spaced around the circumference of the base  31  at different locations from the first set of flywheel mounting holes  32 . The second set of holes  33  are diametrically positioned from each other at a distance of 11.625 inches. The diameter of each hole  33  is 0.395-0.397 inch. 
         [0040]    A third set of flywheel mounting holes  34  comprises three pairs of holes equally spaced around the circumference of the base  31 , i.e., at 120° intervals. For each pair of the mounting holes  34 , the linear distance between adjacent holes is 3.125 inches. The diameter of each hole  34  is 0.315-0.316 inch. The third set of flywheel mounting holes  34  are located the same radial distance from the center of the adapter ring  30  as the first set of flywheel mounting holes  32 . 
         [0041]    As shown in  FIG. 6 , a first set of three dowel pin holes  35  are equally spaced around the circumference of the adapter ring  30  at different locations from the first, second and third sets of holes  32 ,  33  and  34 . The dowel pin holes  35  may be used to locate the adapter ring  30  on the flywheel and align the mounting holes of the adapter ring  30  to the flywheel. The dowel pin holes  35  are located the same radial distance from the center of the adapter ring  30  as the first set of flywheel mounting holes  32 . The diameter of each dowel pin hole  35  is 0.252-0.253 inch. 
         [0042]    As shown in  FIG. 6 , the adapter ring  30  also includes a first set of nine recessed spot faces  36  comprising semi-circular recesses in the raised portions  17  located as shown. The spot faces extend axially along the entire height H of the raised portions  17 . The spot faces  36  are reliefs to allow a socket or wrench to contact a head of a bolt (not shown) passing through an adjacent flywheel mounting hole  32  or  34  so the bolt can be tightened to the proper torque during installation of the adapter ring  30 . The clearances provided by the recessed spot faces  36  thus allow a socket or wrench to cleanly contact the bolt head. As shown in  FIG. 6 , the adapter ring  30  includes a second set of recessed spot faces  37  adjacent three of the flywheel mounting holes  33  having similar shapes and used for similar purposes as the recessed spot faces  36 . In addition, a third set of spot faces  38  are provided at an end of each raised portion  17  adjacent to three of the flywheel mounting holes  32 . 
         [0043]    The clutch adapter rings of the present invention may be drilled for multiple clutch pattern applications to accommodate many flywheel designs and sizes. It has been found that three different clutch adapter rings, each having multiple flywheel mounting hole arrangements as described herein, enable one clutch assembly model to be used with virtually any type of currently available automotive flywheel. The raised area of the adapter ring allows proper clutch adjustment for proper operation of the pressure plate, clutch discs and clutch floater plate of clutch assemblies. An adapter ring of the present invention having mounting holes for various clutch flywheel patterns, and having a raised area, allows stock or aftermarket clutch assemblies to be bolted on existing stock or aftermarket automotive flywheels. 
         [0044]    The adapter rings of the present invention can be used with most stock releasing mechanisms such as mechanical linkages, cable linkages and hydraulic linkages. They can be used with stock OEM or other aftermarket flywheels, and can be used inside existing stock or aftermarket bellhousings. In certain embodiments, the adapter rings allow the use of multi-disc clutch units that provide greater holding power than OEM and other aftermarket clutch units, and also still fit into OEM and other aftermarket bellhousings. The adapter rings also allow for the use of smaller clutch pressure plates with greater holding power, while at the same time requiring lighter than OEM pedal effort. 
         [0045]    The adapter rings may be made of any suitable material, such as steel, aluminum, titanium or any other material having sufficient strength. The adapter rings may be fabricated by any suitable technique, such as machining to provide the flat base surface and holes for existing flywheel and clutch patterns, and the raised portion for pressure plate and floater plate attachment. 
         [0046]    The adapter rings of the present invention allow the use of existing OEM or other aftermarket flywheels. There is no need to purchase another flywheel when purchasing a new OEM replacement clutch assembly. The adapter rings also allow the use of existing throw-out bearing assemblies, as well as the use of pressure plate assemblies that keep the clutch pedal effort lighter than most OEM applications. Furthermore, the adapter rings may keep the pedal effort and release height the same as in OEM assemblies, and allow the use of multiple discs on OEM or other aftermarket flywheels. The adapter rings match the OEM clutch patterns and dowel pins, and increase the holding power beyond OEM type and other aftermarket clutches. Higher-horsepower engines and drivelines may thus be more readily used within current and future automotive vehicles. 
         [0047]    Whereas particular embodiments of this invention have been described above for purposes of illustration, it will be evident to those skilled in the art that numerous variations of the details of the present invention may be made without departing from the invention as defined in the appended claims.