Internal-combustion engines – Poppet valve operating mechanism – Electrical system
Patent
1987-03-02
1989-07-11
Wolfe, Willis R.
Internal-combustion engines
Poppet valve operating mechanism
Electrical system
F01L 134
Patent
active
048461202
DESCRIPTION:
BRIEF SUMMARY
The invention relates to a method of operating an internal combustion engine as defined in the generic portion of claim 1.
An internal combustion engine of this kind is known, for instance, from DE-OS No. 30 24 109. The gas exchange valve or valves are maintained in their closed position in that an electromagnet is energized and attracts an armature. A spring system biases the valve in the opening direction, so that upon deenergization of the electromagnet the spring system becomes active and opens the valve. However, when the electromagnet is energized its force is sufficient to maintain the armature in the closed position the bias of the spring system notwithstanding.
Hence, it is necessary to use electrical energy to maintain the valve in its closed position.
The task of the invention resides in operating an internal combustion engine equipped with a gas exchange valve in such a manner that the energy requirements are reduced. As used herein, the term gas exchange valve is intended to connote either fuel intake valve or exhaust valve.
The task is solved by the elements enumerated in the main claim.
In accordance with the invention use is made of the fact that during the combustion process high internal pressure develops in the interior of a cylinder which high pressure is acting upon the valve head. Thus the valve is subjected to a force which additionally pushed it against its seat in the direction of closing. During the effectiveness of this force the holding force to be generated by the magnet may therefore be reduced for the magnet need now only compensate for the spring bias less the force acting upon the valve head.
Since the internal pressure of a cylinder is not constant during the combustion process, the flow of current through the electromagnet, in a preferred embodiment of the invention, is controlled, the degree of current flow being dependent from the interior pressure of the cylinder.
It is difficult to derive a direct measure of the interior pressure of the cylinder; however empirical values indicative of the buildup of the interior pressure are available. Therefore, in accordance with a preferred embodiment of the invention the flow of current through the electromagnet may be controlled as a function of time whereby the level of current flow is a function of the empirically determined buildup of interior pressure within the cylinder during a combustion or compression phase.
When the interior pressure in the cylinder exceeds the force of the spring for pushing the valve into its open position the flow of current through the magnet may even be completely discontinued.
For synchronizing the pattern of current flowing through the electromagnet with the build-up of pressure in the cylinder, the instant of ignition may be utilized, for because of the ignition of the mixture within the cylinder the interior pressure rises sharply beginning with the instant of ignition. Thus, the instant of ignition defines the starting point for the buildup of the interior pressure in the cylinder.
The invention is explained hereinafter on the basis of the drawing.
FIG. 1 is a schematic presentation, in longitudinal section, of structure for practicing the invention; and
FIG. 2 is a diagram of the operation of a four cycle piston engine for explaining the invention.
As mentioned supra, the method in accordance with the invention may be practised in an internal combustion engine of the kind disclosed by DE-OS No. 30 24 109. It is essential that the valve arrangement be as follows: A cylinder head 10 encloses the upper portion of the internal chamber 12 of a cylinder within which combustion processes of the kind customary in a combustion engine take place in a known manner. A valve 14, shown in FIG. 1 in its open position, i.e. lifted from its seat, is provided for opening the intake and/or the exhaust. At its shank 16 the valve 14 is provided with an armature plate 18 which may axially oscillate to and fro between pole faces of a magnet 20 and a magnet 22. When the armature plate 18 is attracted against the magn
REFERENCES:
patent: 1038598 (1912-09-01), Kellum
patent: 1096955 (1914-05-01), Rock
patent: 1471861 (1923-10-01), Perrault
patent: 3853102 (1974-12-01), Myers et al.
patent: 3882833 (1975-05-01), Longstaff et al.
patent: 4515343 (1985-05-01), Pischinger et al.
patent: 4544986 (1985-10-01), Buchl
patent: 4614170 (1986-09-01), Pischinger et al.
Hormann Karl
Macy M.
Wolfe Willis R.
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