ISMS - Your source for Logan Clutch and much more.

ISMS™ is an Authorized Distributor for Logan Clutch Corporation Clutches & Brake Products including Air Threading Clutches, Hi-Lo Retrokits, Hi-Speed Conversion Kits, & Electrical-Pneumatic Start-Up Kits.

Call ISMS Toll Free - 800-715-PART

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Logan Clutch Corporation
manufacturers of clutches & brake products
Made in Cleveland, Ohio ●USA

Logan Clutch Corporation offers a complete line of hydraulically or pneumatically actuated industrial clutches and brakes for a variety of wet and dry clutch applications. Markets include: Machine Tool, Marine, Oil Field, Mining, Construction and more.

View Logan Clutch Screw Machine Industry Products & Download Literature

Logan Clutch Applications include: Multi-spindle Screw Machines, Marine Transmissions, Z-Drives, Draw Works, Gearboxes and Over-Center clutches; Tunnel Boring, Road Grinding and Snow Removal Equipment; Deck Winches, Mooring winches, Pump Drives, , Tree Chippers and Tub Grinders - as well as Conventional and High performance friction and steel clutch discs.

Featuring Logan Air Threading Clutches, Logan Hi-Lo Retrokits, & Logan Hi-Speed Conversion Kits for Screw Machines:

Logan Air Threading Clutches

 Logan Air Threading clutch

Logan Clutch Electrical-Pneumatic Start-Up Kit

Optional Electrical-Pneumatic Start-Up Kits are furnished complete with all of the necessary mechanical, pneumatic and electrical components and schematic drawings necessary to make the switch from mechanical to Logan smooth and efficient.
Logan Electrical-Pneumatic Start-Up Kit

Field retrofits take less time, in most cases, since the mechanical portion of the kit is designed to fit within the existing mechanical clutch envelope. All that remains is the plumbing of air lines and the mounting and wiring of a directional control valve, limit switch and bracket.

Step by step, detailed schematics are furnished with each kit.  

How They Work
Logan Air Threading ClutchLogan Air Threading Clutches use your original drive cups or clutch gears to drive the threading spindle. Change of speed is accomplished by a limit switch and a solenoid-activated directional control valve. At the prescribed depth, the limit switch is tripped by the threading slide shaft or a cam, shifting the low-speed clutch to the high-speed clutch and allowing the tap to back out. Slow speed for tapping -- fast speed to back out.

Logan Clutch Hi-Lo Retrokits and 
Hi-Speed Conversion Kits
Logan Hi-Lo Retrokit

Logan Hi-Lo Retrokits and Hi-Speed Conversion Kits are designed to increase productivity, and as a direct result, profitability. 

Logan Hi-Lo & Hi-Speed kits increase productivity

Logan Clutch Retrokit Features:

  • Replaces mechanical clutches, roll clutch, band brake and linkages with air-actuated Logan Clutches.

  • Fast engagement, quick release.

  • Simplifies maintenance -- No disc pack adjustment or slippage.

  • Quick Stop, Power Applied Brake prevents coasting.

  • Modular valving manifold and fittings package with air and electrical schematics are provided.

  • Field retrofitted.

1. How They Work
Simplifies Clutch Maintenance -- No Over Or Under Adjusting
Logan multiple disc air actuated clutches are self adjusting, eliminating the need for mechanical linkages. Pressurizing the Logan cylinder-piston assembly forces the piston to clamp and lock the friction and steel separator discs. Torque is transmitted through to the drive cup. When pressure is removed, release springs separate the separator discs, and maintain a running clearance between the separator and friction discs. The amount of pressure controls the amount of torque. The Piston travel increases automatically to accommodate disc wear, eliminating the need for adjustment.

Positive Crisp Clutch engagement – Increases Productivity
Positive, fast acting Logan clutch engagement allows your screw machine to change speeds much faster and more consistently than conventional mechanical clutch methods. This timesaving translates in greater productivity.

For example: A screw machine utilizing standard high-speed and low-speed mechanical clutches may shift less consistently due to improper adjustment of the mechanical high and low speed clutch disc packs, a worn out mechanical roll clutch, worn linkages or a lose band brake. All of these items require periodic maintenance to maintain a consistent cycle time – and can be a real headache since improper adjustment is difficult to diagnose - unless you stand next to a machine with a stopwatch to detect variation in cycle time. Profitability on many jobs is won or lost based on just a few tenths of a second.

The solution: Air actuated Logan Clutches are self-adjusting, eliminating the need for mechanical adjustment. In addition, Logan Clutches eliminate the need for roll clutches, band brakes, dog levers, linkages etc. – making it easier for the machine to operate without the hassle of constant maintenance and adjustment.

Hidden benefits: Not only do you eliminate maintenance headaches, the machine will now cycle more consistently – every cycle, allowing your maintenance person to focus on more value added activities that will really add savings to your company's bottom line. Also, since the band brake is eliminated, set-up personnel can now position tools closer to the work piece, since tools will no longer dive into the work piece. All of this adds up to better machine utilization - bringing more profits from the same machine.

Now that machine speed changes are controlled with air, it is much easier to install electronic devices such as Microprocessor controls, or cam positioners to further enhance productivity. More detailed information on this subject is covered in our Machine Tool Automation Section.

2. What are the Benefits?

Old-Style Mechanical Clutches - Before

Shifting into High Speed
Conventional mechanical clutches shift into high speed around 40 degrees, and back into low around 215 degrees. The high-speed shift point will vary based on the whether the mechanical high-speed clutch is properly adjusted. For example, if the high-speed clutch is slipping, or sluggish, the shift into high may occur at 50 or 60 degrees – 10 to 20 degrees later than it should. Thus increasing the time it takes to shift back into low speed again.

Shifting into Low Speed
Band brakes are used to slow the high-speed shaft down just after shifting into low. Band brakes require routine adjustment and are notorious for inconsistent operation. Many maintenance mechanics over tighten the band brake to minimize the chance of having the tools coast into the work piece, which can cause sever damage to tooling and the machine. Over tightening the band brake can cause the machine t o shift into low too early, often 10-20 degrees too early. Although this minimizes tool crashes, it ensures that the job may take 10-20% longer than anticipated and quoted – bringing on issues of efficiency and profitability.

Logan Hi-Lo Retrokit - After

Shifting into High Speed
The Logan high-speed clutch is self-adjusting shifting your screw machine into high speed at 20 degrees, 50% faster the old-style mechanical clutches. Since Logan Clutches are self-adjusting, there is no need for your operator or maintenance mechanic to periodically check to see if the high speed or low speed clutch is shifting properly

Shifting into Low Speed
The Logan low speed clutch operates the same way as the high-speed clutch – this time it allowing you to shift into low speed 20 degrees later in the cycle. The inertia of the Logan low speed clutch is so strong – it eliminates the need for a band brake and subsequently the need for the dwell time before going into the cutting cycle of the machine.

Summary: Allowing your machine to shift into high speed 20 degrees earlier and stay in high 20 degrees longer – enables you to gain 40 degrees of additional time in high speed. This benefit reduces the overall cycle time of the machine from 10-20 %. See chart.

Contact ISMS for a quote or more information on Logan Clutch products.

ISMS is your source for Logan Clutch,
Davenport® Machine; CJWinter thread rolls & tooling, Davenport-related products, incl. screw machine tooling; services, accessories including Royal Filtermist Mist Collectors; Swiss Live Tools for Star CNC, Citizen & Swistek machines, & much more.

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Phone Toll Free:  800-715-7278

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