Patent ID: 8282360
Filing Date: 2012-10-09
Classification: F04B

Abstract:
1. A pneumatically operated reciprocating pump comprising two opposed pumping chambers, in each one of which a respective flexible bellow slides between a compressed position and an expanded position, a slide of the two flexible bellows being controlled by shuttle means capable to alternatively let a gaseous fluid in one of the two chambers for expanding the respective flexible bellow, whereby when each one of the two flexible bellows assumes a threshold expanded position it interacts with mechanical means allowing the gaseous fluid to be discharged from the respective chamber, each one of the two flexible bellows having a front end in contact with a shaft that is alternatively pushed by one of the two flexible bellows thus compressing the other, each one of the two chambers being connected to at least one respective suction valve and to at least one respective delivery valve, wherein each delivery valve is provided with compensating elastic means capable to compensate variations of rate of fluid that is pumped by the respective chamber, wherein said shuttle means comprises a pneumatically operated shuttle valve comprising a shaped spool sliding between two limit positions within a perforated cylinder, which shuttle valve is connected, for each chamber, to one or more delivery ducts and to one or more ducts for respectively letting and discharging gaseous fluid in and from the respective chamber, the shuttle valve being capable to alternatively open and close the delivery ducts of the two chambers depending on the position of the spool, the spool being moved by the gaseous fluid coming from a chamber through the respective discharge ducts when the spool is in a position in which the spool opens the delivery ducts of the other chamber, and wherein, for each chamber, said one or more delivery ducts and said one or more discharge ducts are internal to the shuttle valve and to a head covering the respective chamber, the two heads being removably coupled to a pump body, the shuttle valve being fastened to the two heads through hollow screws provided with at least one duct capable to put at least one duct internal to the shuttle valve in communication with at least one duct of the respective head.