.~ Biasing means effects induction stroke of abutment driven, vacuum producing pumping member
DEFINITION
Classification: 417/470
(under subclass 437) Apparatus in which the expansible
chamber pump is disclosed as being utilized for the purpose of producing pressure below that of the surrounding medium (i.e., vacuum pump), the pumping member of which is driven in a chamber collapsing direction by means of an element (e.g., cam) which is unsecured to, and adapted for abutment with the pumping member or portion rigid therewith to drive same, there being provided separate means, other than the pumped fluid, (e.g., spring) associated with the pumping member for continuously urging said pumping member in a chamber expanding direction.
(1) Note. For classification under this definition, the pump must be positively disclosed as being utilized for the purpose of producing a vacuum. Expansible chamber type pumps having the above defined relationship between the pumping member, abutment drive, and biasing means, but which are not disclosed for use in vacuum production are classified below on other features.
SEE OR SEARCH CLASS
92, Expansible Chamber Devices,
129, for an expansible chamber device having an abutment connection between the working member thereof and a power transmission element.
