manufacturers of clutches &
Made in Cleveland, Ohio ●USA
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
Air Threading Clutches
Logan Clutch Electrical-Pneumatic
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.
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.
by step, detailed schematics are furnished with each kit.
Logan 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.
Clutch Hi-Lo Retrokits and
Hi-Speed Conversion Kits
Hi-Lo Retrokits and Hi-Speed Conversion Kits are designed to increase
productivity, and as a direct result, profitability.
Logan Clutch Retrokit
mechanical clutches, roll clutch, band brake and linkages with
air-actuated Logan Clutches.
engagement, quick release.
maintenance -- No disc pack adjustment or slippage.
Stop, Power Applied Brake prevents coasting.
valving manifold and fittings package with air and electrical schematics
How They Work
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
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
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.
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
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.
What are the Benefits?
Mechanical Clutches - Before
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
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.
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.