(under the class definition) Apparatus in which the pump is provided with a valve to control the pump fluid and including means to apply or direct a fluid other than the pump fluid to some portion of the valve.
(1) Note. The fluid may be applied to the valve for various purposes such as lubricating, sealing, cooling, flushing, etc. However, a separate fluid applied to a pump valve portion for the sole purpose of actuating the valve is excluded under this definition. See subclass 507, below, for
such subject matter.
(2) Note. The pre-filling of a chamber containing a valve to form a liquid seal for the valve is considered to be means to apply a fluid to the valve under this definition.
(3) Note. A separate fluid which is injected in or entrained by the pump fluid upstream of the valve so as to intermingle with the pump fluid before contact with the valve is excluded from this definition.
