Abstract: An electrical discharge machining apparatus is disclosed having a frame with a base and a vertical support secured to and extending upwardly from the base. A tank adapted to contain an electrolytic liquid is secured to the vertical support by an adjustment mechanism which enables the vertical position of the tank to be varied. A work holder is optionally pivotally secured to the top of the vertical support and movable between a work position in which the work support and work are aligned with the tank and an inspection position in which the work holder is laterally spaced from the tank. Electrical discharge electrodes are contained within the tank while a servo motor vertically moves the work support with its attached work against the electrodes to perform the machining operation. The electrical discharge apparatus is particularly suited for dental prosthesis applications.

Abstract: The present invention provides a system for detecting leaks in the evaporative emission control system utilized in automotive vehicles. Such control systems include a carbon filled canister having both a vent port and a fuel vapor port. The fuel vapor port, as well as a vapor line from the fuel tank, are connected through a purge valve to the intake manifold of the internal combustion engine. The present invention includes a vent valve which is fluidly connected with the canister vent port. An electronic control system closes both the vent valve and opens the purge valve thereby exposing the evaporative emission control system to the partial vacuum in the intake manifold. After a predetermined time period, the purge valve is closed thus entrapping the partial vacuum in the purge system while a pressure transducer thereafter monitors the partial vacuum in the purge system.