Simple-Fill Inc., which is developing technology to allow vehicles running on compressed natural gas to fill up at home, has raised $170,000 through convertible notes offered to three investors, the company disclosed in a Securities and Exchange Commission filing. The offering this month called for raising a total of $250,000 with the notes, meant to be converted later to equity stakes. The investors were not identified and Simple-Fill executives could not immediately be reached for comment. Simple-Fill…