Diaphragm Pumps with Air Savings Devices

摘要

In at least one illustrative embodiment, a diaphragm pump may comprise a sleeve formed to include (i) a bore extending along a longitudinal axis and (ii) a sleeve port that opens to the bore, and a spool supported in the bore of the sleeve and formed to include a spool port, the spool being configured to move with a diaphragm during at least a portion of a stroke of the diaphragm such that the spool slides relative to the sleeve and, when the diaphragm reaches a turndown position that is between first and second end-of-stroke positions, the spool port aligns with the sleeve port to cause a pilot signal to be supplied to a cut-off valve. At least one of the sleeve and the spool may be rotatable about the longitudinal axis to adjust a location of the turndown position relative to the first and second end-of-stroke positions.

主权项

1. A diaphragm pump comprising:
a first diaphragm that separates a first cavity into a first motive fluid chamber and a first pumped media chamber, the first diaphragm being configured to stroke from a first end-of-stroke position to a second end-of-stroke position in response to compressed fluid being communicated from a compressed fluid inlet to the first motive fluid chamber; a cut-off valve configured to (i) communicate compressed fluid from the compressed fluid inlet to the first motive fluid chamber in response to receiving a first pilot signal and (ii) resist communication of compressed fluid from the compressed fluid inlet to the first motive fluid chamber in response to receiving a second pilot signal; a sleeve formed to include (i) a bore extending along a longitudinal axis and (ii) a first sleeve port that opens to the bore, the first sleeve port being fluidly coupled to the cut-off valve via a pilot line; and a spool supported in the bore of the sleeve and formed to include a first spool port, the spool being configured to move with the first diaphragm during at least a portion of the stroke of the first diaphragm such that the spool slides relative to the sleeve and, when the first diaphragm reaches a turndown position that is between the first and second end-of-stroke positions, the first spool port aligns with the first sleeve port to cause the second pilot signal to be supplied to the cut-off valve via the pilot line; wherein at least one of the sleeve and the spool is rotatable about the longitudinal axis to adjust a location of the turndown position relative to the first and second end-of-stroke positions.