Pump

Claim 2

A pump comprising: a pump body having a pumping chamber; an outlet check valve mounted in said body to allow the escape of fluid forced out of said pump and to prevent the flow thereof backwards therethrough into said pumping chamber; an inlet check valve to allow flow of fluid into said pumping chamber and to prEvent flow of fluid therethrough from inside of said pumping chamber to a point outside thereof, said body including a wall for said pumping chamber; a flexible diaphragm fixed in said body to define said pumping chamber therewith, said pumping chamber being variable in size, said diaphragm being movable toward and away from said wall, said pumping chamber being fluid tight except when one of said valves is open, said body defining a fluid-tight vacuum chamber on the side of said diaphragm opposite the side thereof on which said wall is located; first means fixed to said body inside said vacuum chamber for moving said diaphragm toward said wall; and a vacuum pump fixed to said body, said vacuum pump being connected to pump fluid from inside said vacuum chamber to a point outside thereof, said vacuum pump being positioned inside said vacuum chamber.

Claim 3

The invention as defined in claim 1, wherein second means are provided which connect said first means and said vacuum pump, a cylindrical drive shaft extending through said body from a point exterior thereof to a point inside said vacuum chamber, third means connected to said shaft for driving said first means and said vacuum pump synchronously via said second means, an annular fluid-tight seal fixed in compression between said drive shaft and said body in a position around said drive shaft to minimize fluid leakage into said vacuum chamber around said drive shaft.

Claim 4

The invention as defined in claim 2, wherein said body has a second wall, a second diaphragm fixed in said body, said second wall and said second diaphragm defining a second pumping chamber said vacuum chamber being defined by said body and both of said diaphragms, and inlet and outlet check valves for said second pumping chamber.

Claim 5

The invention as defined in claim 3, wherein said pumping chambers have a predetermined maximum cross section, said diaphragms having a maximum cross section in a plane perpendicular to said walls only slightly greater than said pumping chamber cross section.

Claim 6

The invention as defined in claim 1, wherein said body has a second wall, a second diaphragm fixed in said body, said second wall and said second diaphragm defining a second pumping chamber, said vacuum chamber being defined by said body and both of said diaphragms, and inlet and outlet check valves for said second pumping chamber.

Claim 7

The invention as defined in claim 5, wherein said pumping chamber has a predetermined maximum cross section, said diaphragm having a maximum cross section in a plane perpendicular to said wall only slightly greater than said pumping chamber cross section.

Claim 8

The invention as defined in claim 1, wherein said pumping chamber has a predetermined maximum cross section, said diaphragm having a maximum cross section in a plane perpendicular to said wall only slightly greater than said pumping chamber cross section.

Claim 9

A pump comprising: a housing; flexible diaphragm means sealed in said housing dividing the space therein into inner and outer chamber means, said inner chamber means being evacuated, said diaphragm means including two diaphragms dividing said housing into one inner chamber and two outer chambers, said inner chamber means being said inner chamber, said outer chamber means being said outer chambers; back-up plate means for said diaphragm means, said back-up plate means being a back-up plate for each diaphragm; intake and exhaust check valve means for said outer chamber means, said intake valve means being an intake valve in said housing extending into each outer chamber at the positions of each corresponding back-up plate, said intake valve means also including a leaf spring to bias each intake valve closed, at least one magnet being carried by one of said back-up plate means and said intake valve means, and a ferromagnetic material being carried by the other to open said intake valve means as soon as one corresponding back-up plate is positioned its minimum distance from the corresponding internal surface of said housing In a corresponding outer chamber, a corresponding intake valve thereby being quickly opened at the bottom of the pump stroke to provide for maximum intake efficiency, said housing being made of a nonmagnetic material; and power means to reciprocate said back-up plate means to pump a fluid from said intake valve means to said exhaust valve means, the lower pressure in said inner chamber holding said diaphragm means back to cause said diaphragm means to withdraw fluid from said intake valve means with improved efficiency, said power means including means to reciprocate said back-up plates in unison in a manner to cause the intake valve to open in one outer chamber while the intake valve in the other chamber is closed, and vice versa, so as to pump fluid out of said outer chambers alternately, said diaphragm having a uniform thickness, said housing having a dish-shaped internal surface in each of said outer chambers for each of said diaphragms to contact, said dish-shaped surfaces being flat over a major central portion thereof and being concave toward said inner chamber of the periphery thereof, each said back-up plate having a curvature to mate with each corresponding outer chamber surface.

Claim 10

A pump comprising: a housing; flexible diaphragm means sealed in said housing dividing the space therein into inner and outer chamber means, said inner chamber means being evacuated, said diaphragm means including two diaphragms dividing said housing into one inner chamber and two outer chambers, said inner chamber means being said inner chamber, said outer chamber means being said outer chambers; back-up plate means for said diaphragm means, said back-up plate means being a back-up plate for each diaphragm; intake and exhaust check valve means for said outer chamber means, said intake valve means being an intake valve in said housing extending into each outer chamber at the positions of each corresponding back-up plate, said intake valve means also including a leaf spring to bias each intake valve closed, at least one magnet being carried by one of said back-up plate means and said intake valve means, and a ferromagnetic material being carried by the other to open said intake valve means as soon as one corresponding back-up plate is positioned its minimum distance from the corresponding internal surface of said housing In a corresponding outer chamber, a corresponding intake valve thereby being quickly opened at the bottom of the pump stroke to provide for maximum intake efficiency, said housing being made of a nonmagnetic material; and power means to reciprocate said back-up plate means to pump a fluid from said intake valve means to said exhaust valve means, the lower pressure in said inner chamber holding said diaphragm means back to cause said diaphragm means to withdraw fluid from said intake valve means with improved efficiency, said power means including means to reciprocate said back-up plates in unison in a manner to cause the intake valve to open in one outer chamber while the intake valve in the other chamber is closed, and vice versa, so as to pump fluid out of said outer chambers alternately, said diaphragm having a uniform thickness, said housing having a dish-shaped internal surface in each of said outer chambers for each of said diaphragms to contact, said dish-shaped surfaces being flat over a major central portion thereof and being concave toward said inner chamber of the periphery thereof, each said back-up plate having a curvature to mate with each corresponding outer chamber surface.

Claim 11

The invention as defined in claim 8, wherein each of said intake valves is adapted to be opened by a ferromagnetic material carried thereby and carried by each corresponding back-up plate, the magnet in each case having a sufficient force of attraction to open each corresponding intake valve against the pressure in said outer chambers and against the force of said springs when the corresponding back-up plate is at the bottom of the pump stroke.

Claim 12

The invention as defined in claim 9, wherein each of said intake valves is adapted to be opened by a ferromagnetic material carried by each corresponding back-up plate, the spring for each intake valve being sufficiently strong to overcome the magnetic force of attraction.

Claim 13

The invention as defined in claim 10, wherein said power means includes an auxiliary vacuum pump to withdraw air from said inner chamber means.