摘要 |
A fluid dispensing apparatus including a fluid ejector including a fluid reservoir having fluid, and configured to eject the fluid, a vacuum pump configured to create negative pressure in an activation mode and to create approximately no pressure in a deactivation mode, a meniscus pressure regulator configured to regulate the negative pressure received from the vacuum pump, a leaking member configured to reduce the negative pressure received from the vacuum pump towards or equal to atmospheric pressure in response to the vacuum pump being placed in the deactivation mode, and a back pressure regulator having a pressure reference port to receive the reduced negative pressure from the leaking member and the regulated negative pressure from the meniscus pressure regulator, the back pressure regulator configured to maintain a non-retraction negative pressure value to position a fluid meniscus in a non-retracted state and a retraction negative pressure value to position the fluid meniscus in a retracted state.
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