Coil-on plug capacitive sensors and passive coil-on plug diagnostic system incorporating same

Abstract

A capacitive sensor for a coil-on plug ignition testing apparatus includes a first portion of the capacitive sensor and a second portion of the capacitive sensor, at least one of which has a substantially planar base, and each of which has one or more engagement members projecting downwardly therefrom. One of or both of the first portion and the second portion may be a capacitive element forming a part of the capacitive sensor. The second portion is connected, and is configured to slide relative, to the first portion. A biasing element is disposed between the first and second portions to bias the first portion toward the second portion and to maintain the first portion and second portion in a compressed state. The first portion may be translated relative to the second portion against a bias of the biasing element, to an extended state for securing to a coil-on plug housing. An electrical connector electrically connects the first portion and/or the second portion forming a capacitive element to an output terminal.

1 - 9 . (canceled)  
     
     
         10 . A magnetic mount capacitive sensor for a coil-on plug ignition testing apparatus, comprising: 
 a magnetic mount base;    a movable arm rotatably attached to the magnetic mount base;    a capacitive sensor rotatably attached to the movable arm; and    a conductor connecting the capacitive sensor to an electrical terminal provided on the magnetic mount base.    
     
     
         11 . A magnetic mount capacitive sensor for a coil-on plug ignition testing apparatus according to  claim 10 , wherein the movable arm is configured to rotate along two axes.  
     
     
         12 . A magnetic mount capacitive sensor for a coil-on plug ignition testing apparatus according to  claim 11 , wherein the movable arm comprises at least one of an articulated section having a joint and a telescoping section.  
     
     
         13 . A magnetic mount capacitive sensor for a coil-on plug ignition testing apparatus according to  claim 12 , wherein a distal end of the movable arm comprises a capacitive sensor mount.  
     
     
         14 . A magnetic mount capacitive sensor for a coil-on plug ignition testing apparatus according to  claim 13 , wherein the capacitive sensor is configured to rotate about at least one axis relative to the capacitive sensor mount.  
     
     
         15 . A magnetic mount capacitive sensor for a coil-on plug ignition testing apparatus according to  claim 14 , wherein at least one of the capacitive sensor and the capacitive sensor mount is configured to translate with respect to the movable arm.  
     
     
         16 . A magnetic mount capacitive sensor for a coil-on plug ignition testing apparatus according to  claim 14 , further comprising a non-conductive material applied to an exterior surface of at least a region of at least one of the capacitive sensor, the capacitive sensor mount, and the movable arm.  
     
     
         17 - 20 . (canceled)  
     
     
         21 . A coil-on plug ignition testing apparatus, comprising: 
 a capacitive sensor comprising a magnetic mount base, a movable arm rotatably attached to the magnetic mount base, a capacitive sensor rotatably attached to the movable arm, and a conductor connecting the capacitive sensor to an electrical terminal provided on the magnetic mount base; and    a control circuit comprising a first circuit region comprising a plurality of input electrical connectors connectable to a first plurality of capacitive sensors, a second circuit region comprising a plurality of input electrical connectors connectable to a second plurality of capacitive sensors, the second circuit region provided parallel to the first circuit region, a first capacitor comprising a region of a capacitive divider provided in at least one of the first circuit region and the second circuit region, and a first potentiometer provided in series with the first circuit region and the second region for attenuation of signals input thereto.