Sensing device

• US 4,825,689 A
• Filed: 10/03/1988
• Issued: 05/02/1989
• Est. Priority Date: 01/25/1986
• Status: Expired due to Fees

• Current Assignee: Lucas Industries Limited (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Original Assignee: Lucas Industries Limited (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Inventors: Haworth, Roy, Russell, Michael F.
• Primary Examiner(s): Levy, Stewart J.
• Assistant Examiner(s): Raevis, Robert R.
• Application Number:
  US07/253,948
• Time in Patent Office: 211 Days
• Field of Search: 73/117.3, 73/117.2, 73/116, 250/227
• US Class Current: 73/114.09
• 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: G01J 5/0014 for sensing the radiation from gases, flames
• CPC Class Codes: G01J 5/0018 Flames, plasma or welding
• CPC Class Codes: G01J 5/041 Mountings in enclosures or in a particular environment
• CPC Class Codes: G01J 5/044 Environment with strong vibrations or shocks
• CPC Class Codes: G01J 5/046 Materials; Selection of thermal materials
• CPC Class Codes: G01J 5/08 Optical arrangements
• CPC Class Codes: G01J 5/0887 Integrating cavities mimicking black bodies, wherein the heat propagation between the black body and the measuring element does not occur within a solid; Use of bodies placed inside the fluid stream for measurement of the temperature of gases; Use of the reemission from a surface, e.g. reflective surface; Emissivity enhancement by multiple reflections
• CPC Class Codes: G01J 5/0893 Arrangements to attach devices to a pyrometer, i.e. attaching an optical interface; Spatial relative arrangement of optical elements, e.g. folded beam path G01J5/049 takes precedence
• CPC Class Codes: G01M 15/10 by monitoring exhaust gases or combustion flame

Abstract

A sensing device for use in an internal combustion engine to sense combustion of fuel in a combustion chamber of the engine includes a tubular body part in which is located a radiation conductive element one end of which is exposed to the combustion chamber in use. On the other end of the element is a sensor which in use is connected in an electrical circuit. The sensor is responsive to radiation transmitted along the element from the flame in the combustion chamber. The element is held in a bore of the body part by a visco-elastic lining which also provides a gas tight seal and acts to cushion the element against vibration.

Claims

1. A sensing device for attachment to an internal combustion engine whereby an electrical signal can be obtained indicative of combustion of fuel in a combustion space of the engine comprising in combination, a tubular body part adapted to be secured within an opening in an engine wall, the opening communicating with the combustion space, a radiation conductive element extending within a bore defined by the tubular body part, a sealing lining located between the surface of said element and the wall of the bore, said lining acting to retain the element in the bore and to prevent egress of gases from the combustion space, and a sensor mounted on the end of the element which is remote from the combustion space in use, said sensor having a central area in intimate contact with the entire end of said element and having a peripheral area overlapping said end and secured thereto by a fillet joint extending from said peripheral area to a longitudinal side of said element, said sensor being responsive to the radiation transmitted by the element, the other end of the element in use, being exposed to the combustion space, wherein said lining is formed from a visco-elastic material whereby the lining also acts to cushion the element against vibration and shock.

2. A device according to claim 1 in which said material is a silicone rubber.

3. A device according to claim 1 in which the other end of said element is located against a step defined in the bore.

4. A device according to claim 1 in which said sensor is cemented to the one end of said element.

5. A device according to claim 4 in which said sensor comprises a photo-diode having a light opening facing the end of the element.

6. A device according to claim 1 in which said element is formed from quartz, the element having flame polished end surfaces.

7. An internal combustion engine including a sensing device as claimed in claim 1 in which the tubular body part is located in the opening so that the other end of the element is set back from the entrance to the opening from the combustion space by a distance within the range 3-12 mm.