Serpentine drive system with improved over-running alternator decoupler

A serpentine belt system for an automotive vehicle comprising:

• a drive assembly including an internal combustion engine having an output shaft with a driving pulley thereon rotatable about a driving pulley axis, a sequence of driven assemblies each having a driven pulley rotatable about an axis parallel with said driving pulley axis, and a serpentine belt mounted in cooperating relation with said driving pulley and with said driven pulleys in a sequence which corresponds with the sequence of said driven assemblies when related to the direction of movement of the belt to cause said driven pulleys to rotate in response to the rotation of said driving pulley,
• said sequence of driven assemblies including an alternator assembly including an alternator shaft mounted for rotation about a shaft axis,
• a hub structure fixedly carried by said alternator shaft for rotation therewith about the shaft axis;
• and
• a spring and one-way clutch mechanism coupling said alternator pulley with said hub structure,
• said spring and one-way clutch mechanism comprising a resilient spring member formed separately from and operatively connected in series with a one-way clutch member,
• said resilient spring member being constructed and arranged to transmit the driven rotational movements of said alternator pulley by said serpentine belt to said hub structure such that said alternator shaft is rotated in the same direction as said alternator pulley while being capable of instantaneous relative resilient movements in opposite directions with respect to said alternator pulley during the driven rotational movement thereof,
• said one-way clutch member being constructed and arranged to allow said hub structure and hence the alternator shaft to rotate at a speed in excess of the rotational speed of the alternator pulley when the speed of the engine output shaft is decelerated to a predetermined extent;
• wherein said one-way clutch member comprises a coiled steel structure and a friction material carried by said coiled steel structure, said friction material having a coefficient of friction greater than that for said coiled steel structure;
• and
• wherein said resilient spring member is fixed at one end thereof to said hub structure and connected at an opposite end thereof to said one-way clutch member, said friction material of said one-way clutch member constructed and arranged to frictionally engage said alternator pulley to enable said resilient spring member to transmit the driven rotational movements of said alternator pulley to said hub structure, said friction material constructed and arranged to be in sliding relationship with said alternator pulley to permit the alternator shaft to rotate at said speed in excess of the rotational speed of the alternator pulley when the speed of the engine output shaft is decelerated to said predetermined extent.

A serpentine belt system for an automotive vehicle comprising:

• a drive assembly including an internal combustion engine having an output shaft with a driving pulley thereon rotatable about a driving pulley axis, a sequence of driven assemblies each having a driven pulley rotatable about an axis parallel with said driving pulley axis, and a serpentine belt mounted in cooperating relation with said driving pulley and with said driven pulleys in a sequence which corresponds with the sequence of said driven assemblies when related to the direction of movement of the belt to cause said driven pulleys to rotate in response to the rotation of said driving pulley,
• said sequence of driven assemblies including an alternator assembly including an alternator shaft mounted for rotation about a shaft axis,
• a hub structure fixedly carried by said alternator shaft for rotation therewith about the shaft axis;
• and
• a spring and one-way clutch mechanism coupling said alternator pulley with said hub structure,
• said spring and one-way clutch mechanism comprising a resilient spring member formed separately from and operatively connected in series with a one-way clutch member,
• said resilient spring member being constructed and arranged to transmit the driven rotational movements of said alternator pulley by said serpentine belt to said hub structure such that said alternator shaft is rotated in the same direction as said alternator pulley while being capable of instantaneous relative resilient movements in opposite directions with respect to said alternator pulley during the driven rotational movement thereof,
• said one-way clutch member being constructed and arranged to allow said hub structure and hence the alternator shaft to rotate at a speed in excess of the rotational speed of the alternator pulley when the speed of the engine output shaft is decelerated to a predetermined extent, and
• wherein said resilient spring member and said one-way clutch member are disposed in axially overlapping relation with respect to one another,
• said resilient spring member and said one-way clutch member being connected in series with one another by an intermediate, generally tubular member extending in axially overlapping relation with respect to said resilient spring member and said one-way clutch member;
• wherein said resilient spring member is generally disposed radially inwardly of said tubular member, and wherein said one-way clutch member is generally disposed radially outwardly of said tubular member, said resilient spring member being connected at one end thereof to said hub structure and at an opposite end thereof to said tubular member, said one-way clutch member being connected at one end thereof to said tubular member and having an opposite end portion thereof constructed and arranged to be in friction gripping engagement with said alternator pulley to enable said resilient spring member to resiliently couple said hub structure with said alternator pulley, said one-way clutch member being in surface sliding relation with said alternator pulley to allow said hub structure and hence the alternator shaft to rotate at said speed in excess of the rotational speed of the alternator pulley when the speed of the engine output shaft is decelerated to said predetermined extent.

A serpentine belt system for an automotive vehicle comprising:

• a drive assembly including an internal combustion engine having an output shaft with a driving pulley thereon rotatable about a driving pulley axis, a sequence of driven assemblies each having a driven pulley rotatable about an axis parallel with said driving pulley axis, and a serpentine belt mounted in cooperating relation with said driving pulley and with said driven pulleys in a sequence which corresponds with the sequence of said driven assemblies when related to the direction of movement of the belt to cause said driven pulleys to rotate in response to the rotation of said driving pulley,
• said sequence of driven assemblies including an alternator assembly including an alternator shaft mounted for rotation about a shaft axis,
• a hub structure fixedly carried by said alternator shaft for rotation therewith about the shaft axis;
• and
• a spring and one-way clutch mechanism coupling said alternator pulley with said hub structure,
• said spring and one-way clutch mechanism comprising a resilient spring member formed separately from and operatively connected in series with a one-way clutch member,
• said resilient spring member being constructed and arranged to transmit the driven rotational movements of said alternator pulley by said serpentine belt to said hub structure such that said alternator shaft is rotated in the same direction as said alternator pulley while being capable of instantaneous relative resilient movements in opposite directions with respect to said alternator pulley during the driven rotational movement thereof,
• said one-way clutch member being constricted and arranged to allow said hub structure and hence the alternator shaft to rotate at a speed in excess of the rotational speed of the alternator pulley when the speed of the engine output shaft is decelerated to a predetermined extent;
• and
• wherein said resilient spring member and said one-way clutch member each comprise coiled steel material, and wherein the coils of said resilient spring member and the coils of said one-way clutch member are coiled in an opposite direction from one another, and wherein said resilient spring member expands radially when initially resiliently coupling said hub structure for driven rotation by said alternator pulley.

A serpentine belt system for an automotive vehicle comprising:

• a drive assembly including an internal combustion engine having an output shaft with a driving pulley thereon rotatable about a driving pulley axis, a sequence of driven assemblies each having a driven pulley rotatable about an axis parallel with said driving pulley axis, and a serpentine belt mounted in cooperating relation with said driving pulley and with said driven pulleys in a sequence which corresponds with the sequence of said driven assemblies when related to the direction of movement of the belt to cause said driven pulleys to rotate in response to the rotation of said driving pulley,
• said sequence of driven assemblies including an alternator assembly including an alternator shaft mounted for rotation about a shaft axis,
• a hub structure fixedly carried by said alternator shaft for rotation therewith about the shaft axis;
• and
• a spring and one-way clutch mechanism coupling said alternator pulley with said hub structure,
• said spring and one-way clutch mechanism comprising a resilient spring member formed separately from and operatively connected in series with a one-way clutch member,
• said resilient spring member being constructed and arranged to transmit the driven rotational movements of said alternator pulley by said serpentine belt to said hub structure such that said alternator shaft is rotated in the same direction as said alternator pulley while being capable of instantaneous relative resilient movements in opposite directions with respect to said alternator pulley during the driven rotational movement thereof,
• said one-way clutch member being constructed and arranged to allow said hub structure and hence the alternator shaft to rotate at a speed in excess of the rotational speed of the alternator pulley when the speed of the engine output shaft is decelerated to a predetermined extent;
• and
• wherein said resilient spring member comprises a coil spring fixed at one end thereof to said hub structure and connected at an opposite end thereof to said one-way clutch member, said one-way clutch member comprising a coiled steel structure and a friction material carried by said coiled steel structure, said friction material having a coefficient of friction greater than that for said coiled steel structure, said one-way clutch member having a free end portion thereof biased into engagement with an interior surface of said alternator pulley,
• said friction material at said free end portion of said one-way clutch member constructed and arranged to frictionally engage said alternator pulley when said alternator pulley is initially driven by said belt, and wherein increasing portions of said one-way clutch member extending away from said free end are engaged with said alternator pulley as said alternator pulley continues to be driven until substantially all of said one-way clutch member is engaged with said pulley and rotation from said alternator pulley is imparted through said connection to said resilient spring member so that said resilient spring member resiliently couples said alternator pulley to said hub structure.

A device for transmitting movement from a belt driven by an output shaft of an engine to a shaft of an auxiliary component to be driven, comprising:

• a hub structure constructed and arranged to be fixedly carried by said auxiliary shaft for rotation therewith about a shaft axis;
• a pulley member mounted on said hub structure and constructed and arranged to engage said belt and be rotatably driven thereby;
• and
• a spring and one-way clutch mechanism coupling said pulley member with said hub structure,
• said spring and one-way clutch mechanism comprising a resilient spring member separately formed from and operatively connected in series with a one-way clutch member,
• said resilient spring member being constructed and arranged to transmit the driven rotational movements of said pulley member to said hub structure such that said shaft is rotated in the same direction as said pulley while being capable of instantaneous relative resilient movements in opposite directions with respect to said pulley during the driven rotational movement thereof,
• wherein said resilient spring member is operatively connected at one end thereof to said hub structure and operatively connected at an opposite end thereof to said one-way clutch member,
• said one-way clutch member being spring biased radially outwardly so as to have a portion thereof disposed in frictional engagement with said pulley when said pulley is in a static condition,
• said one-way clutch having increasing portions thereof moved radially outwardly into friction locking engagement with said pulley when said auxiliary shaft is being rotatably driven to thereby rotationally couple said pulley to said resilient spring member and enable said resilient spring member to resiliently transmit the driven rotational movements of said pulley to said hub structure,
• said one-way clutch member being constructed and arranged to allow said hub structure and hence the shaft to rotate at a speed in excess of the rotational speed of the pulley when the speed of the driven pulley is decelerated to a predetermined extent.

A device for transmitting movement from a belt driven by an output shaft of an engine to a shaft of an auxiliary component to be driven, comprising:

• a hub structure constructed and arranged to be fixedly carried by said auxiliary shaft for rotation therewith about a shaft axis;
• a pulley member mounted on said hub structure and constructed and arranged to engage said belt and be rotatable driven thereby;
• and
• a spring and one-way clutch mechanism coupling said pulley member with said hub structure,
• said spring and one-way clutch mechanism comprising a resilient spring member separately formed from and operatively connected in series with a one-way clutch member,
• said resilient spring member being constructed and arranged to transmit the driven rotational movements of said pulley member to said hub structure such that said shaft is rotated in the same direction as said pulley while being capable of instantaneous relative resilient movements in opposite directions with respect to said pulley during the driven rotational movement thereof,
• said one-way clutch member being constructed and arranged to allow said hub structure and hence the shaft to rotate at a speed in excess of the rotational speed of the pulley when the speed of the driven pulley is decelerated to a predetermined extent,
• wherein said one-way clutch member comprises a friction material having a greater coefficient of friction than a material of said resilient spring member, and
• wherein said resilient spring member has a torsional spring rate greater than a torsional spring rate of said one-way clutch member.

A device for transmitting movement from a belt driven by an output shaft of an engine to a shaft of an auxiliary component to be driven, comprising:

• a hub structure constructed and arranged to be fixedly carried by said auxiliary shaft for rotation therewith about a shaft axis;
• a pulley member mounted on said hub structure and constructed and arranged to engage said belt and be rotatably driven thereby;
• and
• a spring and one-way clutch mechanism coupling said pulley member with said hub structure,
• said spring and one-way clutch mechanism comprising a resilient sprint member separately formed from and operatively connected in series with a one-way clutch member,
• said resilient spring member being constructed and arranged to transmit the driven rotational movements of said pulley member to said hub structure such that said shaft is rotated in the same direction as said pulley while being capable of instantaneous relative resilient movements in opposite directions with respect to said pulley during the driven rotational movement thereof,
• said one-way clutch member being constructed and arranged to allow said hub structure and hence the shaft to rotate at a speed in excess of the rotational speed of the pulley when the speed of the driven pulley is decelerated to a predetermined extent,
• wherein said one-way clutch member comprises a coiled steel structure and a friction material carried by said coiled steel structure, said friction material having a coefficient of friction greater than that for said coiled steel structure;
• and
• wherein said resilient spring member is fixed at one end thereof to said hub structure and connected at an opposite end thereof to said one-way clutch member, said friction material of said one-way clutch member constructed and arranged to frictionally engage said pulley to enable said resilient spring member to transmit the driven rotational movements of said pulley to said hub structure, said friction material constructed and arranged to be in sliding relationship with said pulley to permit the hub structure and hence said shaft to rotate at said speed in excess of the rotational speed of the pulley when the speed of the driven pulley is decelerated to said predetermined extent.

A device for transmitting movement from a belt driven by an output shaft of an engine to a shaft of an auxiliary component to be driven, comprising:

• a hub structure constructed and arranged to be fixedly carried by said auxiliary shaft for rotation therewith about a shaft axis;
• a pulley member mounted on said hub structure and constructed and arranged to engage said belt and be rotatably driven thereby;
• and
• a spring and one-way clutch mechanism coupling said pulley member with said hub structure,
• said spring and one-way clutch mechanism comprising a resilient spring member separately formed from and connected in series with a one-way clutch member,
• said resilient spring member being constructed and arranged to transmit the driven rotational movements of said pulley member to said hub structure such that said shaft is rotated in the same direction as said pulley while being capable of instantaneous relative resilient movements in opposite directions with respect to said pulley during the driven rotational movement thereof,
• said one-way clutch member being constructed and arranged to allow said hub structure and hence the shaft to rotate at a speed in excess of the rotational speed of the pulley when the speed of the driven pulley is decelerated to a predetermined extent, and
• wherein said resilient spring member and said one-way clutch member are disposed in axially overlapping relation with respect to one another;
• and
• wherein said resilient spring member and said one-way clutch member are connected in series with one another by an intermediate, generally tubular member extending in axially overlapping relation with respect to said resilient spring member and said one-way clutch member, said resilient spring member being disposed generally radially inwardly of said tubular member, said one-way clutch member being disposed generally radially outwardly of said tubular member, said resilient spring member being connected at one end thereof to said hub structure and at an opposite end thereof to said tubular member, said one-way clutch member being connected at one end thereof to said tubular member and having an opposite end portion thereof constructed and arranged to be in friction gripping engagement with said pulley to enable said resilient spring member to resiliently couple said hub structure with said pulley, said one-way clutch member being in surface sliding relation with said pulley to allow said hub structure and hence said shaft to rotate at said speed in excess of the rotational speed of the pulley when the speed of the pulley is decelerated to said predetermined extent.

A device for transmitting movement from a belt driven by an output shaft of an engine to a shaft of an auxiliary component to be driven, comprising:

• a hub structure constructed and arranged to be fixedly carried by said auxiliary shaft for rotation therewith about a shaft axis;
• a pulley member mounted on said hub structure and constructed and arranged to engage said belt and be rotatably driven thereby;
• and
• a spring and one-way clutch mechanism coupling said pulley member with said hub structure,
• said spring and one-way clutch mechanism comprising a resilient spring member separately formed from and connected in series with a one-way clutch member,
• said resilient spring member being constructed and arranged to transmit the driven rotational movements of said pulley member to said hub structure such that said shaft is rotated in the same direction as said pulley while being capable of instantaneous relative resilient movements in opposite directions with respect to said pulley during the driven rotational movement thereof,
• said one-way clutch member being constricted and arranged to allow said hub structure and hence the shaft to rotate at a speed in excess of the rotational speed of the pulley when the speed of the driven pulley is decelerated to a predetermined extent;
• and
• wherein said resilient spring member comprises a coil spring fixed at one end thereof to said hub structure and connected at an opposite end thereof to said one-way clutch member, said one-way clutch member comprising a coiled steel structure and a friction material carried by said coiled steel structure, said friction material having a coefficient of friction greater than that for said coiled steel structure, said one-way clutch member having a free end portion thereof biased into engagement with an interior surface of said pulley,
• said friction material at said free end portion of said one-way clutch member constructed and arranged to frictionally engage said pulley when said pulley is initially driven by said belt, and wherein increasing portions of said one-way clutch member extending away from said free end are engaged with said pulley as said pulley continues to be driven until substantially all of said one-way clutch member is engaged with said pulley and rotation from said pulley is imparted through said connection to said resilient spring member so that said resilient spring member resiliently couples said pulley to said hub structure.

A serpentine belt drive system for an automotive vehicle comprising:

• a drive assembly including an internal combustion engine having an output shaft with a driving pulley thereon rotatable about a driving pulley axis, a sequence of driven assemblies each having a driven pulley rotatable about an axis parallel with said driving pulley axis, and a serpentine belt mounted in cooperating relation with said driving pulley and with said driven pulleys in a sequence which corresponds with the sequence of said driven assemblies when related to the direction of movement of the belt to cause said driven pulleys to rotate in response to the rotation of said driving pulley,
• said sequence of driven assemblies including an alternator assembly including an alternator shaft mounted for rotation about a shaft axis,
• a hub structure fixedly carried by said alternator shaft for rotation therewith about the shaft axis;
• and
• a spring and one-way clutch mechanism coupling said alternator pulley with said hub structure,
• said spring and one-way clutch mechanism comprising a resilient spring portion disposed in series with a one-way clutch portion, said resilient spring portion having a torsional spring rate at least ten times greater than a torsional spring rate of said one-way clutch portion,
• said resilient spring portion being constructed and arranged to transmit the driven rotational movements of said alternator pulley by said serpentine belt to said hub structure such that said alternator shaft is rotated in the same direction as said alternator pulley while being capable of instantaneous relative resilient movements in opposite directions with respect to said alternator pulley during the driven rotational movement thereof,
• said one-way clutch portion being constructed and arranged to allow said hub structure and hence the alternator shaft to rotate at a speed in excess of the rotational speed of the alternator pulley when the speed of the engine output shaft is decelerated to an extent sufficient to establish the torque between said alternator pulley and said hub structure at a predetermined negative level.

A serpentine belt drive system for an automotive vehicle comprising:

• a drive assembly including an internal combustion engine having an output shaft with a driving pulley thereon rotatable about a driving pulley axis, a sequence of driven assemblies each having a driven pulley rotatable about an axis parallel with said driving pulley axis, and a serpentine belt mounted in cooperating relation with said driving pulley and with said driven pulleys in a sequence which corresponds with the sequence of said driven assemblies when related to the direction of movement of the belt to cause said driven pulleys to rotate in response to the rotation of said driving pulley,
• said sequence of driven assemblies including an alternator assembly including an alternator shaft mounted for rotation about a shaft axis,
• a hub structure fixedly carried by said alternator shaft for rotation therewith about the shaft axis;
• and
• a spring and one-way clutch mechanism coupling said alternator pulley with said hub structure,
• said spring and one-way clutch mechanism comprising a resilient spring portion disposed in series with a helical one-way clutch portion, said one-way clutch portion comprising a material having coefficient of friction greater that a coefficient of friction of a material of said spring portion, said resilient spring member having a torsional spring rate greater than a torsional spring rate of said one-way clutch member,
• said resilient spring portion being constructed and arranged to transmit the driven rotational movements of said alternator pulley by said serpentine belt to said hub structure such that said alternator shaft is rotated in the same direction as said alternator pulley while being capable of instantaneous relative resilient movements in opposite directions with respect to said alternator pulley during the driven rotational movement thereof,
• said one-way clutch portion being constructed and arranged to allow said hub structure and hence the alternator shaft to rotate at a speed in excess of the rotational speed of the alternator pulley when the speed of the engine output shaft is decelerated to a predetermined extent.

A serpentine belt drive system for an automotive vehicle comprising:

• a drive assembly including an internal combustion engine having an output shaft with a driving pulley thereon rotatable about a driving pulley axis, a sequence of driven assemblies each having a driven pulley rotatable about an axis parallel with said driving pulley axis, and a serpentine belt mounted in cooperating relation with said driving pulley and with said driven pulleys in a sequence which corresponds with the sequence of said driven assemblies when related to the direction of movement of the belt to cause said driven pulleys to rotate in response to the rotation of said driving pulley,
• said sequence of driven assemblies including an alternator assembly including an alternator shaft mounted for rotation about a shaft axis,
• a hub structure fixedly carried by said alternator shaft for rotation therewith about the shaft axis;
• and
• a spring and one-way clutch mechanism coupling said alternator pulley with said hub structure,
• said spring and one-way clutch mechanism comprising a resilient spring portion disposed in series with a one-way clutch portion,
• said one-way clutch member being spring biased radially outwardly so as to have a portion thereof disposed in frictional engagement with said alternator pulley when said alternator pulley is in a static condition, said one-way clutch having increasing portions thereof moved radially outwardly into friction locking engagement with said alternator pulley when said alternator pulley is rotatably driven by said belt to drive said alternator shaft,
• said resilient spring portion being constructed and arranged to transmit the driven rotational movements of said alternator pulley by said serpentine belt to said hub structure such that said alternator shaft is rotated in the same direction as said alternator pulley while being capable of instantaneous relative resilient movements in opposite directions with respect to said alternator pulley during the driven rotational movement thereof,
• said one-way clutch portion being constructed and arranged to allow said hub structure and hence the alternator shaft to rotate at a speed in excess of the rotational speed of the alternator pulley when the speed of the engine output shaft is decelerated to a predetermined extent.

A serpentine belt drive system for an automotive vehicle comprising:

• a drive assembly including an internal combustion engine having an output shaft with a driving pulley thereon rotatable about a driving pulley axis, a sequence of driven assemblies each having a driven pulley rotatable about an axis parallel with said driving pulley axis, and a serpentine belt mounted in cooperating relation with said driving pulley and with said driven pulleys in a sequence which corresponds with the sequence of said driven assemblies when related to the direction of movement of the belt to cause said driven pulleys to rotate in response to the rotation of said driving pulley,
• said sequence of driven assemblies including an alternator assembly including an alternator shaft mounted for rotation about a shaft axis,
• a hub structure fixedly carried by said alternator shaft for rotation therewith about the shaft axis;
• and
• a spring and one-way clutch mechanism coupling said alternator pulley with said hub structure,
• said spring and one-way clutch mechanism comprising a resilient spring member formed separately from and operatively connected in series with a one-way clutch member,
• said resilient spring member comprising a helical coil torsion spring, being constructed and arranged to transmit the driven rotational movements of said alternator pulley by said serpentine belt to said hub structure such that said alternator shaft is rotated in the same direction as said alternator pulley while being capable of instantaneous relative resilient movements in opposite directions with respect to said alternator pulley during the driven rotational movement thereof, said torsion spring having the helical coils thereof oriented to expand radially when initially transmitting the rotational movements of said alternator pulley to said hub structure
• said one-way clutch member being constructed and arranged to allow said hub structure and hence the alternator shaft to rotate at a speed in excess of the rotational speed of the alternator pulley when the speed of the engine output shaft is decelerated to a predetermined extent.