Regeneration system for particulate trap

• US 5,105,619 A
• Filed: 02/12/1990
• Issued: 04/21/1992
• Est. Priority Date: 02/13/1989
• Status: Expired due to Fees

• Current Assignee: Isuzu Motors Limited
• Original Assignee: Isuzu Motors Limited
• Inventors: Arai, Minoru
• Primary Examiner(s): Hart, Douglas
• Application Number:
  US07/478,951
• Time in Patent Office: 799 Days
• Field of Search: 60/274, 60/286, 60/277, 55/283, 55/DIG. 30
• US Class Current: 60/286
• CPC Class Codes: F01N 2390/02 using electric components only
• CPC Class Codes: F01N 3/023 using means for regenerating the filters, e.g. by burning trapped particles by electrically controlling the supply of combustible mixture or its constituents only F02D41/0235
• CPC Class Codes: F01N 3/027 using electric or magnetic heating means
• CPC Class Codes: F01N 3/032 during filter regeneration only
• CPC Class Codes: F01N 3/32 using air pump using jet air pumps F01N3/34; pumps in general F04
• CPC Class Codes: F01N 9/002 of filter regeneration, e.g. detection of clogging
• CPC Class Codes: F02B 3/06 with compression ignition compression ignition engines using air or gas for blowing fuel into compressed air in cylinder F02B13/02
• CPC Class Codes: F02D 2041/0022 for diesel engines by throttle control
• CPC Class Codes: F02D 35/0038 by means of air pumps
• CPC Class Codes: F02D 41/1441 Plural sensors
• CPC Class Codes: Y02T 10/40 Engine management systems
• CPC Class Codes: Y10S 55/30 Exhaust treatment

Abstract

A regeneration system for a particulate trap provided in an exhaust pipe of an engine in which the temperature rising rate of the front temperature of the trap is calculated from the output of a temperature sensor to control the air flow from an air pump, so that the temperature rising rate may be confined within a predetermined range and the front temperature may be raised up to a predetermined ignition value.

Claims

1. A regeneration system for a particulate trap provided in an exhaust pipe of an engine, comprising;

sensing means for sensing the temperature at the front of said trap,

an air pump for supplying air flow for the front of said trap,

heating means for electrically heating said trap, and,

control means for energizing said heating means and said air pump upon the regeneration of said trap and then for calculating the temperature rising rate of the front temperature of said trap from the output of said sensing means to control the air flow from said air pump so that said temperature rising rate may be confined within a predetermined range, thereby raising the front temperature of said trap up to a predetermined ignition value.

2. A regeneration system for a particulate trap provided in an exhaust pipe of an engine according to claim 1, wherein said control means deenergizes said heating means and fixes the air flow from said air pump at a predetermined value when the front temperature of said trap reaches the predetermined ignition value.

3. A regeneration system for a particulate trap provided in an exhaust pipe of an engine according to claim 2, wherein said control means deenergizes said air pump when a predetermined time interval has lapsed after said heating means had been deenergized.

4. A regeneration system for a particulate trap provided in an exhaust pipe of an engine according to claim 1, further comprising pressure sensing means for sensing the pressure difference between the front pressure and the rear pressure of said trap, said control means initiating the regeneration of said trap when the pressure difference sensed by said pressure sensing means exceeds a predetermined value.

5. A regeneration system for a particulate trap provided in an exhaust pipe of an engine according to claim 4, further comprising:

an inlet valve provided at the front of said trap in the exhaust pipe; and

a bypass valve provided in a bypass pipe across said trap, said control means closing said inlet valve and opening said bypass valve when the regeneration of said trap is initiated, while opening said inlet valve and closing said bypass valve when the regeneration of said trap is completed.