 |
|
|
The X Teeth Variable Cam is similar to the PWM Variable Cam except that pulse width is not considered. Such cams have X equidistant teeth. A cam trigger shall be issued each time a synchronous edge is observed, synchronized with the edge selected in the Variable Cam Phase block.
Such patterns can be utilized by all available sensing technologies.
Those crank encoders that support a single synchronization point can utilize this variable cam configuration. The implementation is able to determine halfcycle information from a cam like this that can move relative to the crank provided a window can be defined relative to the synchronization point that will always encapsulate a tooth on one halfcycle and will not contain a tooth in the other halfcycle. The system will not operate as expected if this windowing condition is not met on the cam that is providing halfcycle information to the crank encoder.
A cam that is only being used to provide cam phaser position is not constrained by these location rules. Thus only the cam being used by the crank encoder for halfcycle information, which is nominally the cam phaser allocated on the CAM resource, would have such a restriction in a dual cam phaser system.
This cam, when used with the 36 minus 2 crank encoder, detects the halfcycle position by looking for the presence or absence of a cam tooth within the 12 tooth window after the missing tooth region.