Diesel engine exhaust particulate filter with intake throttling incineration control

A diesel engine exhaust filter and particulate incineration system in combination with a diesel engine having a normally unthrottled air induction system for admitting combustion air to the engine and an exhaust system for carrying off spent combustion products exhausted from the engine, said filter and incineration system comprising:

• a combustion resistant filter disposed in the exhaust system and operative to collect and retain portions of the largely carbonaceous particulate matter contained in the engine exhaust products, said filter being capable of withstanding without substantial damage internal temperatures sufficient to burn the collected particulate matter, but being incapable of withstanding without damage sustained temperatures above a predetermined level higher than said particulate combustion temperatures,
• a throttle in the induction system and operable to restrict air flow into the engine to reduce the admittance of excess combustion air and thereby increase engine exhaust gas temperature, and
• actuating and control means responsive to the exhaust products temperature in said filter and operative to actuate said throttle periodically during engine operation to an air flow restricting burn mode capable of raising the particulates in said filter to their combustion temperature under certain engine operating conditions and to maintain said throttle mode for a predetermined interval adequate to burn retained particulates in the filter, said actuating and control means being further operative to modulate the throttle position during the periodic burn mode to prevent the combustion temperature within the filter from exceeding said predetermined temperature level above which damage to the filter may occur.