You can start checking on the status of your return within 24 hours after we have received your electronically filed tax return or 4 weeks after you mail a paper tax return. Q7: How often does Whereâs My Refund? update? Whereâs My Refund? updates are made no more than once per day, usually at night.
How Piezo Injectors Work. The heart of a Piezo (short for piezoelectric) injector is the piezo crystal. When electricity is applied to the crystal, it rapidly expands, thus making it suitable to act as the actuator in a diesel fuel injector.ressurized fuel is delivered to the top of this needle as well, the force of which keeps the needle closed. When the piezo crystal is energized, a valve at the top of the needle opens, allowing the pressurized fuel at the top of the needle to return to the tank through the return line.
How does a phoropter work (mechanically)? There seem to be some really neat gear/clutch mechanisms at work throughout the device, what are the actual mechanisms involved? For instance, how does the axis adjustment knob adjust all the astigmatic lenses and the cross cylinder at the same time? Or how does the fast sphere knob work?