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    Grinder Insight Series | Part Driving Methods

    Toyoda Blog

    Grinder Insight Series | Part Driving Methods

    Posted by Shane Farrant on Jul 5, 2018 9:54:01 AM

    In the final Grinder Insight edition, Toyoda’s experts have compiled a helpful list of part driving methods - highlighting each of their strengths and challenges. With a variety of available part driving methods, understanding all your options helps garner the best solution for your part.

    Interested in reading past editions? Take a look below for a comprehensive resource into your Grinder’s capabilities.

    Want to read Part 1: Machine Design? Click Here!
    Want to read Part 2: Machine Options? Click Here! 
    Want to read Part 3: Machine Setup? Click Here! 

    Part 4: What are my available part driving methods?

    DRIVE DOG: [$ Starting Cost]Cam lock Drive Dog

    Drive dogs, such as cam lock or screw type, are driven by a drive pin mounted onto the drive plate on the face of the workhead. During production, the workpiece with drive dog are inserted between centers with the drive pin driving the dog.

    Advantages:
    - Effective and easy to use
    - Easier to hold part roundness between centers when compared to a live workhead
     
    Disadvantages:
    - Increased setup labor time
    - Increased tooling requirements
     
    Screwlock Drive DogsCam Lock
    Left: Screwtype, Right: Cam Lock

    THREE/FOUR JAW CHUCKS: [$$ Starting Cost]

    Three JawFour Jaw

    ThreeversusFour


    COLLET CHUCK: [$$$ Starting Cost]Collet

    Requiring a live workhead center, a collet chuck uses mechanical force to apply full circumferential clamping around the OD or ID of the part.  Collet chucks are often times used during second operations for stronger accuracy and precision.

    Advantages:
    Allows fast clamping and collet change
    - An ideal choice for grinding when the part cannot run between centers
    - Tighter concentricity
    - Offers higher speeds for jobs featuring smaller parts with consistent diameters
     
    Disadvantages:
    - Can be difficult to maintain high precision roundness specifications
    - Since they are ideal for smaller parts with consistent diameters this limits the range of qualified workpieces
    - Due to larger axial length, available distance between centers for the workpiece is reduced.
     
    Toyoda offers 40mm diameter through hole for larger part diameters.

    DUAL CENTER DRIVING WORKHEADS: [$$$ Starting Cost]Center Driving Workheads

    Found on Toyoda’s e300, e500, GL5, and TG4, the dual center driving workheads use two live center workheads that advance and engage the workpiece on both ends. The workpiece is then driven from the center holes.

    Advantages:
    - Time savers
    - No dogs, collets, chucks, or pins needed
     
    Disadvantages:
    - Moderate to high up-front cost
    - Live centers may limit achievable accuracy

    FACE DRIVERS: [$$$$ Starting Cost]Face Driver

    Face drivers use a fixed point and drive pins that rigidly locks the part between the workhead and footstock center points.

    Advantages:
    - High precision
    - Automation
    - Reduced labor setup
     
    Disadvantages:
    - Most susceptible to deflection with less rigid parts
    - Drive pins can affect part end face
    - Live center required for footstock

    ELASO DRIVERS/TOYODA CRAB CHUCK: [$$$ Starting Cost]Elaso Drivers

    Elaso: With a clamping range of 4.9mm to 110mm, Elaso drivers work automatically without the need for auxiliary switch gears. Through manual or automatic loading, Elaso driver jaws open/close through driver housing’s inertial force.

    Advantages:
    - Higher production efficiency by reducing setup time
    - Great choice for automation
    Elasso
    - No additional drive dogs or special workhead 
    requirements
    - Can run between live or dead centers
    - Low maintenance
     
    Disadvantages:
    - Can reduce distance available between centers
    - Requires unit & jaw set for part diameter range
     
     
    Crab (2)

    Crab: Using a dead workhead built for a hydraulic chuck, Toyoda’s Crab Chucks are a customizable solution available in a 10mm to 50mm or 50mm to 100mm capacity.

    Advantages:
    - Allows automatic driving of the part between centers
     
    Disadvantages:
    - Can reduce distance available between centers
    - Requires unit & jaw set for part diameter range 
    Image 1: Elaso credit to CIRO Products Ltd.

    Toyoda, a global leader in grinding machine technology, offers a range of high-performance universal, cylindrical, camshaft, and crankshaft grinding machines all specifically designed to excel in the most demanding of applications.  Contact Shane for additional questions at sfarrant@toyoda.com.

    Written by Shane Farrant

    Shane Farrant is the National Product Manager for Grinders at JTEKT Toyoda Americas.