McMaster-Carr logo
    Enter e-mail addresses in the fields below
    Message
    Cancel
    Comments
    E-mail address (if you would like a response)
    65 Products

    Soft-Start Centrifugal Clutches
    3D CAD models available

    Disengaged until they rotate fast enough to transmit torque, these clutches give the components on your driven side a smooth start by allowing the driving side to start without load.
    Friction Engagement
    Image of Product. Front orientation. Clutches. Shaft-to-Shaft with ​​​​​​​​ ​Engagement Springs.
    Image of Product. Front orientation. Clutches. Shaft-to-Shaft with ​​​​​​​​ ​Support Rollers.

    Shaft-to-Shaft with

    ​​​​​​​​ ​Engagement

    Springs

    Shaft-to-Shaft

    with

    ​​​​​​​​ ​Support

    Rollers

    Image of Product. Front orientation. Clutches. Through Shaft with ​​​​​​​​ ​Support Rollers and Pulley.

    Through Shaft

    with

    ​​​​​​​​ ​Support

    Rollers and Pulley

    Shaft-to-Shaft—Shaft-to-shaft clutches also act as a shaft coupling, allowing you to regulate torque transmission between two shafts.
    Through Shaft—Through-shaft clutches regulate torque transmission between an input shaft and a mounted component.
    ​​​​​​​​ ​Support Rollers—Clutches with support rollers are quieter and last longer than other centrifugal clutches because the contact points are supported by urethane rollers to prevent slipping.
    ​​​​​​​​ ​With Pulley—Clutches with a pulley come ready to install a V-belt.
    Set-Screw Shaft Mount—Clutches that mount to shafts with set screws bite into your shaft when tightened to hold it.
    Clutch Engagement Springs—Clutch engagement springs allow you to change the speed at which the clutch engages.
    Misalignment
    Capability
    Clockwise-and-Counterclockwise Drive
    For Shaft
    Dia.
    For Shaft
    Type
    Engagement
    Speed, rpm
    Max. Power,
    hp
    Max. Rotation
    Speed, rpm
    Pitch
    Dia.
    For Belt
    Trade Size
    Parallel
    Angular
    OD
    Overall
    Lg.
    Keyway Wd. ×
    Keyway Dp.
    Material
    Shaft Mount
    Type
    Each
    Shaft-to-Shaft with ​​​​​​​​ ​Engagement Springs
    5/8"Keyed830133,600____0.003"0.25°4 3/16"2 1/2"3/16" × 3/32"SteelSet Screw000000000000000
    3/4"Keyed830133,600____0.003"0.25°4 3/16"2 1/2"3/16" × 3/32"SteelSet Screw00000000000000
    1"Keyed830133,600____0.003"0.25°4 3/16"2 1/2"1/4" × 1/8"SteelSet Screw00000000000000
     
    Shaft-to-Shaft with ​​​​​​​​ ​Support Rollers
    1/2"Round1,1007.51,750________3 63/64"3 19/64"__SteelSet Screw00000000000000
    5/8"Keyed1,1007.51,750________3 63/64"3 19/64"3/16" × 3/32"SteelSet Screw00000000000000
    3/4"Keyed1,1007.51,750________3 63/64"3 19/64"3/16" × 3/32"SteelSet Screw00000000000000
    1"Keyed1,1007.51,750________3 63/64"3 17/64"1/4" × 1/8"SteelSet Screw00000000000000
     
    Through Shaft with ​​​​​​​​ ​Support Rollers and Pulley
    5/8"Keyed1,1007.51,7502.8"4L, A____3 63/64"1 7/8"3/16" × 3/32"SteelSet Screw00000000000000
    5/8"Keyed1,1007.51,7503.3"4L, A____3 63/64"1 7/8"3/16" × 3/32"SteelSet Screw00000000000000
    3/4"Keyed1,1007.51,7502.8"4L, A____3 63/64"1 7/8"3/16" × 3/32"SteelSet Screw00000000000000
    3/4"Keyed1,1007.51,7503.3"4L, A____3 63/64"1 7/8"3/16" × 3/32"SteelSet Screw00000000000000
     

    Electric One-Way Clutches

    Unlike mechanical clutches, these clutches let you electrically control when torque is transmitted. They transfer torque in one direction and spin freely in the opposite direction, so they’re useful in applications where you don’t want motion to reverse such as in backstopping, indexing, and overrunning. When you remove power from these clutches, they disengage, cutting torque to your pulley, sprocket, gear, or other mounted component without stopping your drive shaft.
    Friction Engagement
    Image of Product. Front orientation. Clutches. Electric One-Way Clutches.
    Through Shaft—Through-shaft clutches regulate torque transmission between an input shaft and a mounted component.
    Clockwise Drive
    Counterclockwise Drive
    For Shaft
    Dia.
    For Shaft
    Type
    Max. Torque,
    in·lbf
    Max. Rotation
    Speed, rpm
    OD
    Overall
    Lg.
    Electric
    Clutch Type
    Electrical
    Connection
    Permanence
    Shaft Mount
    Type
    Wire Lead
    Lg.
    Voltage,
    V DC
    Current,
    amp
    Each
    Current,
    amp
    Each
    Through Shaft
    1/4"Round301,4001 1/4"1 1/8"Power OnHardwireSpring Pin15"240.1400000000000000.240000000000000
    5/16"Round301,4001 1/4"1 1/8"Power OnHardwireSpring Pin15"240.140000000000000.24000000000000
    3/8"Round751,4001 3/4"1 1/2"Power OnHardwireSpring Pin18"240.1400000000000000.240000000000000
    1/2"Round751,4001 3/4"1 1/2"Power OnHardwireSpring Pin18"240.1400000000000000.240000000000000
     

    One-Way Clutches
    3D CAD models available

    Since they transfer torque in one direction and spin freely in the other, these clutches are useful in applications where you don’t want motion to reverse, such as in backstopping, indexing, and overrunning. For example, they can be used to prevent a conveyor from reversing direction.
    When choosing a clutch, consider how much torque you need to transfer. You should also consider how the clutch will attach to your mounted component.
    Roller Engagement—Knurled Hub
    Image of Product. Front orientation. Clutches. One-Way Clutches, Roller Engagement—Knurled Hub.
    Roller clutches are best for low- to medium-torque transfer in overrunning and indexing applications.
    Clutches with a knurled hub can be press fit into the bore of your component.
    Through Shaft—Through-shaft clutches regulate torque transmission between an input shaft and a mounted component.
    Set-Screw Shaft Mount—Clutches that mount to shafts with set screws bite into your shaft when tightened to hold it.
    Shaft
    Hub
    Clockwise Drive
    Counterclockwise
    Drive
    For Shaft
    Dia.
    For Shaft
    Type
    Max. Torque,
    ft·lbf
    Max. Rotation
    Speed, rpm
    OD
    Overall
    Lg.
    Material
    Keyway Wd. ×
    Keyway Dp.
    Mount
    Type
    Dia.
    Lg.
    Each
    Each
    Through Shaft
    1/4"Round0.835,00015/16"31/32"Steel__Set Screw5/8"9/32"0000000000000000000000000000
    3/8"Keyed4.165,0001 3/16"1"Steel3/32" × 3/64"Set Screw9/16"3/8"00000000000000000000000000
    1/2"Keyed502,0001 1/2"1 9/32"Steel1/8" × 1/16"Set Screw7/8"1/2"00000000000000000000000000
     
    Roller Engagement—Keyed Hub
    Image of Product. Front orientation. Clutches. One-Way Clutches, Roller Engagement—Keyed Hub.
    Roller clutches are best for low- to medium-torque transfer in overrunning and indexing applications.
    Clutches with a keyed hub let you slip on your component.
    Through Shaft—Through-shaft clutches regulate torque transmission between an input shaft and a mounted component.
    Slip-Fit Shaft Mount—Clutches that mount to shafts with a slip fit must be secured with a shaft collar or in some other way that prevents them from moving along the length of your shaft.
    Shaft
    Hub
    Clockwise Drive
    For Shaft
    Dia.
    For Shaft
    Type
    Max. Torque,
    ft·lbf
    Max. Rotation
    Speed, rpm
    OD
    Overall
    Lg.
    Material
    Keyway Wd. ×
    Keyway Dp.
    Mount
    Type
    Dia.
    Lg.
    Keyway Wd. ×
    Keyway Dp.
    Each
    Through Shaft
    1/4"Keyed51,8001 5/8"1 15/16"Steel3/16" × 1/16"Slip Fit7/8"13/16"3/16" × 3/32"00000000000000
    3/8"Keyed141,8002"2 1/8"Steel3/16" × 1/16"Slip Fit1 1/4"1"3/16" × 3/32"0000000000000
    1/2"Keyed141,8002"2 1/8"Steel3/16" × 1/16"Slip Fit1 1/4"1"3/16" × 3/32"0000000000000
    5/8"Keyed281,5002 5/8"2 23/32"Steel3/16" × 1/16"Slip Fit1 3/8"1 5/16"3/16" × 3/32"0000000000000
    3/4"Keyed1001,0003 5/8"3 11/32"Steel3/8" × 3/16"Slip Fit2 1/4"1 1/2"3/8" × 3/16"0000000000000
    1"Keyed1001,0003 5/8"3 11/32"Steel3/8" × 3/16"Slip Fit2 1/4"1 1/2"3/8" × 3/16"0000000000000
    1 1/4"Keyed1001,0003 5/8"3 11/32"Steel3/8" × 3/16"Slip Fit2 1/4"1 1/2"3/8" × 3/16"0000000000000
    1 1/2"Keyed2008004 1/2"4 1/2"Steel3/8" × 3/16"Slip Fit3"2 1/16"3/8" × 3/16"0000000000000
     
    Sprag Engagement—Keyed Hub
    Image of Product. Front orientation. Clutches. One-Way Clutches, Sprag Engagement—Keyed Hub.
    Sprag clutches handle higher torque than roller clutches because they have more contact points. This makes them best for backstopping applications.
    Clutches with a keyed hub let you slip on your component.
    Through Shaft—Through-shaft clutches regulate torque transmission between an input shaft and a mounted component.
    Set-Screw Shaft Mount—Clutches that mount to shafts with set screws bite into your shaft when tightened to hold it.
    Max. Rotation
    Speed, rpm
    Shaft
    Hub
    Clockwise Drive
    Counterclockwise
    Drive
    For Shaft
    Dia.
    For Shaft
    Type
    Max. Torque,
    ft·lbf
    Inner-Race
    Outer-Race
    OD
    Overall
    Lg.
    Material
    Keyway Wd. ×
    Keyway Dp.
    Mount
    Type
    Dia.
    Lg.
    Keyway Wd. ×
    Keyway Dp.
    Each
    Each
    Through Shaft
    5/8"Keyed1101,9509002"2 3/4"Steel3/16" × 3/32"Set Screw1 1/4"1"3/16" × 3/32"00000000000000000000000000000000
    3/4"Keyed3001,9507502.88"3.19"Steel3/16" × 3/32"Set Screw1 3/8"1 5/16"3/16" × 3/32"000000000000000000000000000000
    1"Keyed4501,6506003 1/4"3.56"Steel1/4" × 1/8"Set Screw1 3/4"1 7/16"1/4" × 1/8"000000000000000000000000000000
    1 1/4"Keyed6751,2503503 3/4"3 1/2"Steel5/16" × 5/32"Set Screw2 1/4"1 7/16"5/16" × 5/32"000000000000000000000000000000
     
    Sprag Engagement—Without Hub
    Image of Product. Front orientation. Clutches. One-Way Clutches, Sprag Engagement—Without Hub.
    Image of Product. Front orientation. Clutch Covers.

    Clutch Covers

    Image of ProductInUse. Torque Arm Shown Installed. Front orientation. Clutch Torque Arms.

    Torque Arm Shown Installed

    Image of Product. Front orientation. Clutch Torque Arms.

    Clutch Torque Arms

    Sprag clutches handle higher torque than roller clutches because they have more contact points. This makes them best for backstopping applications.
    Clutches without a hub have a precision ground outer race, so they can be press fit directly into a component and positioned anywhere along the length of your shaft. They also have mounting holes on their face you can use to secure your component or an anti-rotation device, such as a torque arm, for a different backstopping setup.
    Through Shaft—Through-shaft clutches regulate torque transmission between an input shaft and a mounted component.
    Slip-Fit Shaft Mount—Clutches that mount to shafts with a slip fit must be secured with a shaft collar or in some other way that prevents them from moving along the length of your shaft.
    Clutch Covers—Covers protect you from rotating equipment when the clutch is mounted to the end of the shaft.
    Clutch Torque Arms—Clutch torque arms work as an anchor for clutches in backstopping applications. Mount to the outer race of your clutch and a stationary piece of equipment.
    Max. Rotation
    Speed, rpm
    Shaft
    Clockwise or
    Counterclockwise Drive
    Clutch Covers
    Clutch
    Torque Arms
    For Shaft
    Dia.
    For Shaft
    Type
    Max. Torque,
    ft·lbf
    Inner-Race
    Outer-Race
    OD
    Overall
    Lg.
    Material
    Keyway Wd. ×
    Keyway Dp.
    Mount
    Type
    Each
    Each
    Each
    Through Shaft
    3/4"Keyed3002,8008503 1/2"2 3/4"Steel3/16" × 3/32"Slip Fit0000000000000000000000000000000000000000000000
    1"Keyed1,1752,5008004 1/4"3 1/2"Steel1/4" × 1/8"Slip Fit0000000000000000000000000000000000000000000
    1 1/4"Keyed1,1752,5008004 1/4"3 1/2"Steel1/4" × 1/8"Slip Fit0000000000000000000000000000000000000000000
    1 1/2"Keyed2,2502,2007505 3/8"3 3/4"Steel3/8" × 3/16"Slip Fit0000000000000000000000000000000000000000000
    1 3/4"Keyed2,2502,2007505 3/8"3 3/4"Steel3/8" × 3/16"Slip Fit0000000000000000000000000000000000000000000
     

    Electric Clutches for Face-Mount Motors
    3D CAD models available

    Designed to mount directly to a NEMA face-mount motor, these clutches let you electrically control when to transmit power without turning off your motor. When you remove power to these clutches, they stop power transmission by disconnecting your motor's load. To the other side, attach a gearbox or couple a gear, sprocket, pulley, or other component.
    Friction Engagement
    Image of Product. Front orientation. Clutches. Electric Clutches for Face-Mount Motors.
    Through Shaft—Through-shaft clutches regulate torque transmission between an input shaft and a mounted component.
    Set-Screw Shaft Mount—Clutches that mount to shafts with set screws bite into your shaft when tightened to hold it.
    Clutch Controllers—Clutch controllers (sold separately) convert an AC input into a DC output to engage and disengage these clutches. They mount inside an electrical enclosure (sold separately).
    Electrical Enclosures—Electrical enclosures (sold separately) attach directly to these clutches to protect wiring from dust and moisture.
    Clutch Covers—Clutch covers (sold separately) change the open design of these clutches into a totally enclosed fan-cooled unit, protecting them from dust and moisture.
    Clockwise-and-Counterclockwise Drive
    Max. Torque,
    ft·lbf
    Max. Power,
    hp
    Max. Rotation
    Speed, rpm
    For Motor Frame
    Size
    OD
    Overall
    Lg.
    Electric
    Clutch Type
    Electrical
    Connection
    Permanence
    Shaft
    Dia.
    Keyway Wd. ×
    Keyway Dp.
    Material
    Shaft Mount
    Type
    Wire Lead
    Lg.
    Voltage,
    V DC
    Certification
    Current,
    amp
    Each
    Through Shaft
    163/43,600NEMA 48Y, NEMA 56C6 3/4"6 3/4"Power OnHardwire5/8"3/16" × 3/16"SteelSet Screw36"90UL Listed, C-UL Listed0.2000000000000000000
    3033,600NEMA 48Y, NEMA 56C6 3/4"6 3/4"Power OnHardwire5/8"3/16" × 3/16"SteelSet Screw36"90UL Listed, C-UL Listed0.230000000000000000
     

    Noncontact Magnetic Electric Brakes
    3D CAD models available

    Image of Product. Front orientation. Brakes. Noncontact Magnetic Electric Brakes.
    Create drag to slow or stop the motion of your drive system using magnetic force. Because torque is transmitted by magnetic force without contact, there is no wear, so these brakes give you accurate, repeatable braking. Also known as electric hysteresis brakes, they are often used in tensioning, holding, and stopping applications. The brake engages when the power is on and releases when it is off. The amount of electrical current determines the amount of torque that is applied by the brake. Use these brakes with a current-limiting transformer.
    Keyway
    Mounting
    Hole
    Shaft
    Dia.
    Max. Torque,
    in·lbf
    Max. Rotation
    Speed, rpm
    OD
    Overall
    Lg.
    Shaft
    Type
    Wd.
    Dp.
    Electric
    Brake Type
    Drive Direction
    Electrical
    Connection
    Permanence
    Wire Lead
    Lg.
    Voltage,
    V DC
    Thread
    Size
    Thread
    Pitch, mm
    Each
    Through Shaft
    0.118"0.21,9901 1/4"1 5/8"Round____Power OnClockwise and CounterclockwiseHardwire18"24M2.5
    0.4500000000000000
    0.197"0.81,2001 13/16"2"D-Profile____Power OnClockwise and CounterclockwiseHardwire18"24M2.5
    0.450000000000000
    0.197"1.37602"2 1/8"D-Profile____Power OnClockwise and CounterclockwiseHardwire18"24M3
    0.50000000000000
    0.276"3.55702 3/8"3"D-Profile____Power OnClockwise and CounterclockwiseHardwire18"24M4
    0.70000000000000
    0.394"115903 5/8"4"D-Profile____Power OnClockwise and CounterclockwiseHardwire18"24M4
    0.70000000000000
    0.472"195004 7/16"4 7/8"Keyed0.158"0.098"Power OnClockwise and CounterclockwiseHardwire18"24M5
    0.80000000000000
    0.59"324205 7/16"5 1/8"Keyed0.197"0.124"Power OnClockwise and CounterclockwiseHardwire18"24M5
    0.8000000000000000
     
    back to top