Rammer for tank gun loading: US Pat. No. 7,674,199

U.S. Patent No. 7,674,199, issued on March 9, 2010 to Meggitt Defense Systems, Inc. of Irvine, CA, discloses a rigidizable chain for use in loading ammunition rounds into the breach of a tank gun.

Large-caliber tank guns utilize a rammer to load the ammunition rounds into the gun breach with sufficient force and speed to position the rounds (which can weigh 110 pounds or more) properly.  In view of the space limitations, these rammers are designed to be stowable.  Previously-used rammers are described by the patent as being complex, expensive, or suffering from large “jerking” movements due to fluctuations in transverse velocity or acceleration.  The patent discloses that its rigidizable chain ”produces a significantly smoother chain movement and rammer action.”

Meggitt produces various ammunition handling systems for tanks and helicopters, one of which is the “Stryker mobile gun system replenisher” for 105mm mobile gun systems, which includes a “self-locking zipperchain rammer” which might be covered by the ’199 patent. 

 The ’199 patent issued with an additional 902 days of patent term (the time that the patent may be asserted against accused infringers).  The standard patent term is 20 years from the filing date of the patent application, however, in certain circumstances, additional time may be granted to make up for delays in the USPTO’s handling of the patent application.  In a recent federal appeals court decision, it was found that the USPTO was using an incorrect algorithm to calculate the ”patent term adjustments.”  As a result, the patent term adjustments for certain recently issued U.S. patents are eligible to be recalculated by the USPTO upon request by the patentee.