Pump for zinc-rich materials or the like

Claim 2

A pumping system comprising a source containing a zinc-rich coating material having a solid content of at least about 45 percent by volume or the like, a pump having an inlet connected to said source operable to pump said coating material from said source to said outlet at a substantially increased pressure, said pump including a pair of relatively movable members cooperating to define a variable volume pump chamber the volume of which is changed by relative movement of said members, inlet and outlet check valves for controlling the flow of said coating material to and from said chamber, at least one of said valves including a spherically curved seat element and a ball valve element formed with mating surfaces of substantial area which are engagable to prevent backflow through said one valve, the area of the mating surface on said seat element being at least about 15 percent of the total area of said ball element, at least one of said mating surfaces being provided by elastomeric material operating to distribute the force of engagement between said elements evenly over said mating surfaces.

Claim 3

A pumping system as set forth in claim 1 wherein said zinc-rich coating material has a water base, said one valve is said inlet check valve, and said mating surface of said valve seat has an area from about 15 percent to about 35 percent of the total area of said ball valve element.

Claim 4

A pumping system as set forth in claim 2 wherein said elastomeric material is provided by said ball valve element and said seat element is provided with a curved relief at least along the inlet side of said spherical seat.

Claim 5

A pumping system as set forth in claim 3 wherein said ball valve element is provided with a rigid core and a layer of elastomeric material enclosing said core.

Claim 8

A method as set forth in claim 5 wherein said one ball check valve is the inlet valve, the area of said mating surface of said seat is from about 15 percent to about 35 percent of the total area of the ball.

Claim 9

A method as set forth in claim 6 including forming a curved relief on the seat of the ball check valve at least along the inlet side of the seat therein.

Claim 10

In a pumping system including a source of zinc-rich coating material having a solid content of at least about 45% by volume or the like, a pump having an outlet and an inlet connected to said source operable to pump said coating material from said source to said outlet at a substantially increased pressure, said pump including a pair of relatively movable members cooperating to define a variable volume pump chamber the volume of which is changed by relative movement of said members, inlet and outlet check valves for controlling the flow of said coating material to and from said chamber, the improvement comprising at least one of said valves including a spherically curved metal valve seat and a ball check valve comprising a substantially rigid metal core encased within a layer of elastomeric material, said valve seat and said ball check valve having mating surfaces of substantial area with substantially the same radius of curvature, said mating surface of said valve seat having an area at least about 15% of the total area of said ball, said valve seat being provided with a curved relief adjacent to the inlet side of said spherically curved seat, said surfaces being engagable to prevent backflow through said one valve.

Claim 11

In a pumping system including a source of zinc-rich coating material having a solid content of at least about 45% by volume or the like, a pump having an outlet and an inlet connected to said source operable to pump said coating material from said source to said outlet at a substantially increased pressure, said pump including a pair of relatively movable members cooperating to define a variable volume pump chamber the volume of which is changed by relative movement of said members, inlet and outlet check valves for controlling the flow of said coating material to and from said chamber, the improvement comprising at least one of said valves including a spherically curved metal valve seat and a ball check valve comprising a substantially rigid metal core encased within a layer of elastomeric material, said valve seat and said ball check valve having mating surfaces of substantial area with substantially the same radius of curvature, said mating surface of said valve seat having an area at least about 15% of the total area of said ball, said valve seat being provided with a curved relief adjacent to the inlet side of said spherically curved seat, said surfaces being engagable to prevent backflow through said one valve.

Claim 12

The improvement set forth in claim 8 wherein said layer of elastomeric material is polyurethane.

Claim 13

The improvement set forth in claim 9 wherein said one valve is the inlet valve, and said mating surface of said valve seat has an area from about 15 percent to about 35 percent of the total area of said ball check valve.

Claim 14

In an airless spray pump for liquid coating material including a pair of relatively movable members cooperating to define a variable volume pump chamber the volume of which is changed by relative movement of said members, an inlet and an outlet to said chamber, inlet and outlet check valves for controlling flow to and from said chamber, the improvement comprising at least one of said valves including a spherically curved metal valve seat and a ball check valve comprising a substantially rigid metal core encased within a layer of elastomeric material, said valve seat and said ball check valve having mating surfaces of substantial area with substantially the same radius of curvature, said mating surface of said valve seat having an area at least about 15 percent of the total area of said ball check valve, said surfaces being engagable to prevent backflow through said one valve.

Claim 15

In an airless spray pump for liquid coating material including a pair of relatively movable members cooperating to define a variable volume pump chamber the volume of which is changed by relative movement of said members, an inlet and an outlet to said chamber, inlet and outlet check valves for controlling flow to and from said chamber, the improvement comprising at least one of said valves including a spherically curved metal valve seat and a ball check valve comprising a substantially rigid metal core encased within a layer of elastomeric material, said valve seat and said ball check valve having mating surfaces of substantial area with substantially the same radius of curvature, said mating surface of said valve seat having an area at least about 15 percent of the total area of said ball check valve, said surfaces being engagable to prevent backflow through said one valve.

Claim 16

The improvement set forth in claim 11 wherein said layer of elastomeric material is polyurethane.

Claim 17

The improvement set forth in claim 11 wherein said one valve is said inlet valve.

Claim 18

The improvement set forth in claim 13 wherein said mating surface of said valve seat has an area from about 15 percent to about 35 percent of the total area of said ball check valve.