Apparatus and method for protecting engine electronics from radio frequency interference
AssigneeBrunswick Corporation
InventorArthur O. Fitzner
Life of this patent
Estimating the term…
Abstract
A system and method for its implementation for suppressing RFI effects on an electronic control module enclosed in a metal housing includes inserting a plurality of high frequency shunts in the wires attached to the module through the housing. The shunts, comprising by-passing capacitors include one capacitor on the incoming wire disposed closely adjacent the housing and grounded thereto and another capacitor on each wire disposed closely adjacent the connection of the wire to the active circuit of the module and grounded to the circuit ground network. The housing includes a direct connection to ground and the ground network for the electronic module has a single ground connection to the housing.
Claims15
In an electronic control module including electronic circuit means, a metal housing and external conductors extending through the housing and having electrical connections to the circuit means, a system for suppressing RFI signals induced in the conductors and entering the electronic module via the conductors comprising:
- an external ground connection to the housing;
- first RFI voltage shunt means connecting each conductor to the housing closely adjacent its entry through the housing;
- second RFI voltage shunt means connecting each conductor to the ground network for the circuit means closely adjacent the connection of the conductor to the circuit means;
- and,
- a single ground connection between the housing and the ground network for the circuit means.
A method of suppressing engine spark ignition RFI in an electronic engine control module including a metal housing enclosing the module, circuit board means within the housing, and external conductors extending through the housing and operatively connected to the circuit board means, the method comprising the steps of:
- (1) grounding the housing to the engine block;
- (2) inserting first RFI shunt means between the housing and each conductor closely adjacent its entry to the housing;
- (3) inserting second RFI shunt means between each conductor and the ground network for the circuit board means closely adjacent the connection of said conductor to the circuit board means;
- and,
- (4) establishing a single ground connection between the housing and the ground network for the circuit board means.
A system for suppressing the effects of engine spark ignition RFI on an electronic module comprising:
- a grounded metal housing enclosing the circuit means;
- external conductors extending into the housing and connected to the circuit means;
- a plurality of high frequency shunts from each of the conductors to ground;
- one of said shunts on each conductor disposed closely adjacent the point of entry of the conductor into the housing and conductively attached thereto;
- another of said shunts on each conductor disposed closely adjacent the point of connection of the conductor to the circuit means and conductively attached to the circuit means ground network;
- and,
- a single ground connection between the housing and the circuit means ground network.
Dependencies are inferred from the claim text.