ENGINE SPARK CONTROL AND EXHAUST GAS RECIRCULATION VACUUM SIGNAL SELECTOR

• US 3,783,847 A
• Filed: 12/06/1972
• Issued: 01/08/1974
• Est. Priority Date: 12/06/1972
• Status: Expired due to Term

• Current Assignee: Dale A. Kolody
• Original Assignee: Dale A. Kolody
• Inventors: Kolody, Dale A.
• Primary Examiner(s): Burns, Wendell E.
• Application Number:
  US05/312,445
• Time in Patent Office: 398 Days
• Field of Search: 123/119A,117A 192/.092 74/860
• US Class Current: 123/406.7
• CPC Class Codes: F02D 37/02 one of the functions being ignition
• CPC Class Codes: F02M 2026/009 EGR combined with means to change air/fuel ratio, ignition timing, charge swirl in the cylinder
• CPC Class Codes: F02M 26/57 using electronic means, e.g. electromagnetic valves

Abstract

An engine emission control system includes exhaust gas recirculating and engine spark timing devices each normally connected respectively to axially spaced EGR and spark ports in the carburetor induction passage above the closed position of the throttle valve. Valving is provided under the control of temperature changes and changes in the operation of the vehicle transmission to at times switch the connections to the exhaust recirculating device from EGR port to spark port operation and vice versa, to at times improve emissions while maintaining a constant vehicle drive quality, and at other times improve vehicle drive quality while maintaining a constant emission level.

Claims

1. A carburetor controlled servo system comprising in combination, a vacuum servo having a force movable member variably movable by vacuum applied thereto, a carburetor having an induction passage open at one end to ambient air at essentially atmospheric pressure and connected at its opposite end to engine intake manifold vacuum so as to subject the passage to varying engine pressure depressions, a throttle valve rotatably movable across the passage between essentially closed and wide open throttle positions, a number of pressure sensing ports in the induction passage axially spaced from each other along the induction passage and located above the closed position of the throttle valve in a position to be traversed progressively by the edge of the throttle valve as it moves from a closed position towards the wide open throttle position, means connecting the servo to one of the ports for actuating the force transmitting member, and further means for switching the connection of the servo from the one port to another of the remaining number of ports for varying the movement of the force transmitting member for the same movement of the throttle valve.

2. A servo system as in claim 1, the further means including temperature sensitive means responsive to the attainment of a predetermined temperature for switching the connection of the servo from the one port to the another port.

3. A servo system as in claim 1, the force movable member comprising a valve movable to control the recirculation of engine exhaust gases from the exhaust system to the induction system as a function of movement of the servo, the another port constituting a spark port and being located below the one port closer to the closed position of the throttle valve.

4. A servo system as in claim 3, the further means including ambient temperature sensitive means responsive to the attainment of a predetermined engine temperature to connect the spark port to the first mentioned servo above the predetermined temperature level to increase exhaust gas recirculation flow for the same throttle valve setting as when the one port is connected to the first mentioned servo.

5. A control system as in claim 4, the further means also including check valve means in the connection between the one port and the first mentioned servo preventing communication of the higher pressure in the one port to the latter servo when the spark port is connected to the latter servo.

6. A control system as in claim 3, the further means including a second valve movable between first and second positions respectively blocking a connection between or connecting the spark port and the servo and a check valve in the connection between the one port and the servo operable to prevent communication of the higher pressure in the one port to the servo when the second valve is in the second position while permitting communication of the higher pressure in the one port to the servo when the second valve is in the first position.

7. A control system as in claim 6, including a second servo connected to an engine distributor spark adjustment means movable in opposite directions to advance and retard respectively the engine spark timing as a function of servo movement, means connecting the second servo to the spark port, the second servo having a second force movable member variably movable by spark port vacuum applied thereto.

8. A control system as in claim 6, the further means including an ambiEnt temperature sensitive means responsive to the attainment of a predetermined ambient temperature level for moving the second valve from its first position to its second position.

9. A control system as in claim 6, the further means including additional means operable in response to the attainment of a predetermined condition of operation of a transmission associated with the engine for moving the second valve from its first position to its second position.

10. A control system as in claim 9, the further means including ambient temperature sensitive means responsive to the attainment of a predetermined engine temperature level for also moving the second valve from its first position to its second position.

11. A control system as in claim 8, the second valve being solenoid controlled and movable to the second position when energized, operation of the ambient temperature sensitive means energizing the second valve.

12. A control system as in claim 7, the second valve having three ports the first of which is connected to the spark port while a second port is connected to the first mentioned servo and the third is connected to the second servo, this first position being an at rest position and interconnecting the first and third ports, the second position interconnecting the first and second ports.

13. A control system as in claim 7, the second valve being solenoid controlled and movable to the second position when energized, operation of the ambient temperature sensitive means energizing the second valve, the second valve comprising first and second solenoid controlled valve means, the first being normally closed and solenoid opened to connect the spark port and first mentioned servo, the second being normally open to connect the spark port to the second servo and being solenoid closed, both valve means being energized in response to operability of the ambient temperature sensitive means.

14. An engine spark timing and exhaust gas recirculation control comprising in combination, a carburetor induction passage having a throttle valve rotatably mounted therein and movable between closed and fully open positions, a spark port in the induction passage located above the closed position of the throttle valve, an exhaust gas recirculation (EGR) port located in the induction passage above and axially spaced from the spark port, an (EGR) servo having an (EGR) valve connected thereto spring biased in a closed direction and movable to an open position by vacuum applied to the servo, the (EGR) valve controlling flow of exhaust gases back into the engine induction system, first conduit means connecting the (EGR) port to the (EGR) servo, a second servo having a force transmitting member connected thereto spring biased in one direction and connected to the movable spark adjusting member of an engine distributor and movable in opposite directions to advance or retard the spark, second conduit means connecting the spark port to the second servo, valve means interconnecting the first and second conduit means movable between a first position connecting the spark port to the second servo while disconnecting the spark port from the (EGR) servo and a second position disconnecting the spark port from the second servo while connecting the spark port to the (EGR) servo, a check valve in the first conduit means between the (EGR) port and the connection to the second conduit means to prevent decay of spark port vacuum acting on the (EGR) servo by the (EGR) port pressure, and further means for moving the valve means between its positions to change the pressure level acting on the (EGR) servo for the same degree of throttle opening and also to control the advance or retard of the engine spark timing.

15. A control as in claim 14, the further means including an ambient temperature responsive means operable above a predetermined temperature level to effect movement of the valve means from its first to its second position to provide more vacuum acting on the (EGR) servo for the same throttle opening.

16. A control as in claim 14, the further means including transmission responsive means sensitive to a predetermined transmission operation for effecting movement of the valve means from the first position to the second position.

17. A control as in claim 16, the valve means being solenoid movable from the first to the second position, conditioning the transmission for low and intermediate gear operations above the predetermined temperature energizing the solenoid to move the valve means to its second position providing (EGR) flow as a function of spark port vacuum level and no spark port flow to the second servo, conditioning the transmission for high speed operation de-energizing the valve means solenoid to move the valve means to its first position providing (EGR) flow as a function of (EGR) port vacuum and spark timing adjustment as a function of spark port vacuum.