Spray head assembly

Claim 2

A spray head comprising: body means including passageway means therein; discharge orifice means connected with said passageway means; a first inlet for material to be sprayed connected with said passageway means upstream from said orifice means; a second inlet having a predetermined cross-sectional area for actuating air and connected with said passageway means between said orifice means and said first inlet; means providing an air restriction having a cross-sectional area less than said predetermined area between said orifice means and said second inlet; a valve seat disposed in said passageway means between said inlets; a valve element engageable with said seat for blocking said passageway means and preventing the flow of material to be sprayed therethrough; said body means including a chamber behind said valve element and communicating with said air inlet; a piston slidable in said chamber and connected with said valve element; said piston being operable by back pressure provided by the actuating air for opening said valve element and spring means within said body means and engaging said piston for normally biasing the valve element against the valve seat; said valve seat comprising an element of relatively soft material presenting an annular edge; and said valve element being formed of relatively hard material.

Claim 3

A spray head, as defined in claim 1, which includes an adjustable stop element mounted in said body means and projecting into said chamber for engaging said piston and limiting opening of the valve element for controlling the flow of material to be sprayed.

Claim 4

A spray head, as defined in claim 1, wherein said valve seat element is formed of plastic, said valve element being pointed and engaging said edge with substantially line contact.

Claim 5

A spray head comprising: body means including passageway means therein; discharge orifice means connected with said passageway means; a first inlet for material to be sprayed connected with said passageway means upstream from said orifice means; a second inlet having a predetermined cross-sectional area for actuating air and connected with said passageway means between said orifice means and said first inlet; means providing an air restriction having a cross-sectional area less than said predetermined area between said orifice means and said second inlet; a valve seat disposed in said passageway means between said inlets; a valve element engageable with said seat for blocking said passageway means and preventing the flow of material to be sprayed therethrough; said body means including a chamber behind said valve element and communicating with said air inlet; a piston slidable in said chamber and connected with said valve element; said piston being operable by back pressure provided by the actuating air for opening said valve element; and spring means within said body means and engaging said piston for normally biasing the valve element against the valve seat; said body means comprising a main body member having said passageway means therein; said passageway means including a first section and a second larger diameter section defining a chamber; said orifice means comprising a nozzle member having a discharge orifice at its outer end and a tubular inner end extending into said chamber and having a predetermined internal diameter; a fitting mounted within said body member and including a first portion in said first passageway section and having said valve seat thereon and a second tubular portion extending into said tubular nozzle section and having an external diameter less than said predetermined diameter and cooperating with said tubular nozzle section for providing said air restriction; said fitting having a bore extending therethrough from the valve seat and communicating with the nozzle.

Claim 6

A spray head comprising: body means including passageway means therein; discharge orifice means connected with said passageway means; a first inlet for material to be sprayed connected with said passageway means upstream from said orifice means; a second inlet having a predetermined cross-sectional area for actuating air and connected with said passageway means between said orifice means and said first inlet; means providing an air restriction having a cross-sectional area less than said predetermined area between said orifice means and said second inlet; a valve seat disposed in said passageway means between said inlets; a valve element engageable with said seat for blocking said passageway means and preventing the flow of material to be sprayed therethrough; said body means including a chamber behind said valve element and communicating with said air inlet; a piston slidable in said chamber and connected with said valve element; said piston being operable by back pressure provided by the actuating air for opening said valve element; and spring means within said body means and engaging said piston for normally biasing the valve element against the valve seat; said body means comprising a main body member having said passageway means therein; said passageway means including a first section and a second larger diameter section defining a chamber; said orifice means comprising a nozzle member having a discharge orifice at its outer end and a tubular inner end extending into said chamber and having a predetermined internal diameter; a fitting mounted within said body member and including a first portion in said first passageway section and having said valve seat thereon and a second tubular portion extending into said tubular nozzle section and having an external diameter less than said predetermined diameter and cooperating with said tubular nozzle section for providing said air restriction; said fitting having a bore extending therethrough from the valve seat and communicating with the nozzle.

Claim 7

A spray head, as defined in claim 4, wherein said body means includes a supplementary body member connected with said main body member and cooperating therewith in defining said first mentioned chamber, said spring means comprising a compression spring disposed between an end wall of said supplementary body member and said piston.

Claim 8

A spray head, as defined in claim 5, which comprises an adjustable stop element extending through said end wall of the supplementary body member for engaging the piston and limiting opening movement of the valve element for controlling the rate of floW of the material being sprayed during a spraying operation.