Bulletin number: SB103-1

Category: Safety

Date issued: April 29, 2003

Machine models: ASC prefeeders.

Subject: Unexpected retracting of the extendo.

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To our valued customer:

This service bulletin is part of an ongoing effort to provide quality service and support for all Alliance Machine Systems International, LLC products. If you need assistance or more information, please call Gary Kneale, Field Service Manager, at 509-535-0356 and select Option two.

The prefeeder extendo conveyor is used to shingle blocks of corrugated into the finishing machine hopper.  The extendo is comprised of two, telescoping sections.  The section with the tamping system, located closest to the die cutter, is called extendo section 2.  Extendo section 2 is extended and retracted with a power adjust mechanism.

There is a possibility that the power adjust mechanism may fail allowing the extendo section 2 to unexpectedly retract to the full-in position.  There is a possibility that a person may be struck by the tamper arm or the end of extendo operator station if a failure occurs.

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There are two designs that have been identified for review.

1. ASC Block Push Bottom Feeder and Standard Bottom Feeder extendos

There is a possibility that the power adjust pinion or spur gear may shear a tooth due to fatigue.  If the machine matches this configuration, please do the following:

1. The original pinion and spur gears should be replaced with heat-treated gears of equivalent size.  Reference Martin part #SXXXX-H.  Note, the “S” designates steel gears with a 14 ý¡ pressure angle, the “X’s” designate the diametral pitch and number of gear teeth, and the H designates heat-treated gears with 0.40% carbon steel.

2. Verify the gears are vertically aligned.  The entire width of the gear teeth between mating gears must be in contact.  If the gears are not vertically aligned, reposition the gears to provide the proper contact.  Note, the shaft on the pinion gear will not be flush with the face of the gear.

3. Inspect the new pinion, spur and rack gears on a monthly basis to verify there are no signs of excessive wear, cracks or missing teeth.  



Figure 1.  Power adjustment system, ASC Block Push Bottom Feeder

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2. ASC Top Feeder extendos

There is a possibility that the power adjust spur gears or sprockets may shear a tooth or the chain may fail due to fatigue or stretching.  If the machine matches this configuration, please do the following:

1. Inspect the spur gears, rack gears and sprockets on a monthly basis to verify there are no signs of excessive wear, cracks or missing teeth.  Inspect the chain on a monthly basis to verify there are no signs of excessive wear or damage.

2. Verify the spur gear and rack gears are in alignment.  Verify that the two chain sprockets are in alignment.

3. If one of the two spur gears need to be replaced, then replace both gears with heat-treated gears of equivalent size.  Reference Martin part #SXXXX-H.  Note, the “S” designates steel gears with a 14 ý¡ pressure angle, the “X’s” designate the diametral pitch and number of gear teeth, and the H designates heat-treated gears with 0.40% carbon steel.

Figure 2.  Power adjustment system, ASC Top Feeder

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