Capacitive Ignition System

• US 20130206123A1
• Filed: 01/16/2013
• Published: 08/15/2013
• Est. Priority Date: 01/17/2012
• Status: Active Grant

• Current Assignee: MAN Energy Solutions SE (Volkswagen AG)
• Original Assignee: Man Diesel & Turbo SE (Volkswagen AG)
• Inventors: DIRUMDAM, Bjrn, Soler, Edwin Cruz
• Granted Patent: US 10,815,955 B2
• Time in Patent Office: Days
• US Class Current: 123/634
• CPC Class Codes: F02P 1/08 Layout of circuits
• CPC Class Codes: F02P 11/02 Preventing damage to engines or engine-driven gearing
• CPC Class Codes: F02P 3/08 Layout of circuits for low tension F02P3/10
• CPC Class Codes: F02P 3/0846 using digital techniques F02P3/0869, F02P3/0892, F02P3/096 take precedence
• CPC Class Codes: F02P 3/0876 the storage capacitor being charged by means of an energy converter (DC-DC converter) or of an intermediate storage inductance
• CPC Class Codes: F02P 7/06 of circuit-makers or -breakers, or pick-up devices adapted to sense particular points of the timing cycle
• CPC Class Codes: F02P 7/0634 Details of cams or cam-followers
• CPC Class Codes: F02P 9/002 Control of spark intensity, intensifying, lengthening, suppression by means of current control in the storage devices F02P3/05, F02P3/09, during starting F02P15/12

Abstract

A capacitive ignition system for an internal combustion engine includes a voltage converter which has two primary terminals and two secondary terminals a primary voltage source has two voltage source terminals (A+, A−) which are connected in each instance to one of the primary terminals so that a primary circuit is formed; a switch which is incorporated within the primary circuit and a controller so that the switch can be closed and opened; a first control device constructed to actuate the controller in accordance with an ignition pattern for closing and/or opening; an electrical capacitance (C1, C2) within the primary circuit; and a second control device (25) constructed to maintain constant a voltage rise at the secondary terminals, which occurs in order to reach the ignition voltage, as the ignition energy requirement of an ignition device connected to the secondary terminals changes.

Claims

1. A capacitive ignition system for an internal combustion engine comprising:

a voltage converter (40) having a plurality of primary terminals and a plurality of secondary terminals, said voltage converter (40) constructed to convert a voltage applied to said primary terminals into a higher voltage that can be tapped at said secondary terminals by an ignition device (31) of the internal combustion engine;

a primary voltage source (10) for supplying a primary voltage, said primary voltage source (10) having a plurality of voltage source terminals (A+, A−

) connected in each instance to one of said primary terminals of said voltage converter (40) so that a primary circuit (20) is formed;

a switch (T1) incorporated within the primary circuit (20), said switch having a controller (T1.1) for opening and closing said switch (T1);

a first control device (21) connected to said controller (T1.1) of said switch (T1), said control device constructed to actuate said controller (T1.1) of said switch (T1) in accordance with a predefined ignition pattern for closing and opening;

an electrical capacitance (C1, C2) incorporated within the primary circuit (20) so as to be chargeable with the primary voltage to a predetermined electric charge when said switch (T1) is open and able to deliver the charge to said primary terminals of said voltage converter (40) over a specific discharge time when said switch (T1) is closed so that the voltage at said secondary terminals of said voltage converter (40) increases to an ignition voltage; and

a second control device (25) configured such that a voltage rise at said secondary terminals occurring in order to reach the ignition voltage is maintained constant as the ignition energy requirement of the ignition device (31) changes.

2. The capacitive ignition system according to claim 1, wherein said second control device (25) is constructed to maintain constant the voltage rise by controlling the specific discharge time as a function of the ignition energy requirement of the ignition device (31).

3. The capacitive ignition system according to claim 2, wherein said second control device (25) is configured to maintain constant the voltage rise by controlling the discharge time so as to remain constant as the ignition energy requirement of the ignition device (31) changes.

4. The capacitive ignition system according to claim 2, wherein said primary circuit (20) comprises an electrical resistance (R1, R2, R3) and an electrical inductance, wherein one of said electrical capacitance (C1, C2), said electrical resistance (R1-R3) and said electrical inductance is constructed so as to be adjustable in value, and wherein said second control device (25) is constructed to control the discharge time for maintaining constant the voltage rise by changing the value of one of the electrical capacitance (C1, C2), of the electrical resistance (R1-R3) and of the electrical inductance.

5. The capacitive ignition system according to claim 4, wherein said second control device (25) is constructed to increase the electrical capacitance (C1, C2) as the ignition energy requirement of the ignition device (31) increases so as to counteract a shortening of the specific discharge time caused by the increase in the ignition energy requirement.

6. The capacitive ignition system according to claim 4, wherein said second control device (25) is constructed to increase the electrical resistance (R1-R3) as the ignition energy requirement of the ignition device (31) increases so as to counteract a shortening of the discharge time caused by the increase in the ignition energy requirement.

7. The capacitive ignition system according to one of claim 4, wherein said second control device (25) is constructed to increase the electrical inductance as the ignition energy requirement of the ignition device (31) increases so as to counteract a shortening of the discharge time caused by the increase in the ignition energy requirement.

8. The capacitive ignition system according to claim 7, wherein said voltage converter (40) comprises a transformer having a primary coil (L1) and a secondary coil L2), and wherein the electrical inductance is formed by the transformer.

9. The capacitive ignition system according to claim 2, wherein said second control device (25) is constructed to change a level of the primary voltage as a function of the ignition energy requirement of the ignition device (31) while simultaneously controlling the discharge time.

10. The capacitive ignition system according to claim 9, wherein said second control device (25) is constructed to increase the primary voltage as the ignition energy requirement of the ignition device (31) increases.