Spray gun

Claim 2

An improved airless spray gun comprising: a body; a spray nozzle assembly secured to said body wherein said spray nozzle assembly includes; a passageway extending through said spray nozzle assembly having one end in communication with a source of liquid under pressure, a nozzle opening having a center in communication with the other end of said passageway, a needle member having a tapered surface adapted for cooperation and engagement with a tapered surface of a valve port, said tapered surface of said needle member defining a needle angle, a seat member positioned in said passageway between the ends thereof housing said valve port whose tapered surface defines a seat angle, said seat member positioned in said passageway such that the projected extension of the tapered surface of said needle member converges and intersects at approximately the center of said nozzle opening when said needle member is in contact with the tapered surface of said valve port, a chamber extending from said seat member to said nozzle opening; and means for moving said needle member into contact and out of contact with the tapered surface of said valve port thereby defining a closed position and an open position respectively of said needle member.

Claim 3

The improved airless spray gun of claim 1 wherein the end of said chamber extending from said seat member is substantially greater in cross-sectional area than said valve port and the other end converging toward and conforming to said nozzle opening.

Claim 4

The improved airless spray gun of claim 1 wherein said means for moving said needle member into contact and out of contact with the tapered surface of said valve port includes a stop member for limiting the rearward movement of said needle member out of contact with the tapered surface of said valve port and thEreby the size of the opening between said needle member and the tapered surface of said valve port.

Claim 5

The improved airless spray gun of claim 3 wherein the longitudinal position of said stop member is adjustable thereby causing the rearward movement of said needle member and the opening between said needle member and the tapered surface of said valve port to be adjustable to thereby accommodate different sizes of nozzle openings at optimum conditions.

Claim 6

The improved airless spray gun of claim 4 wherein said means for moving said needle member into contact and out of contact with the tapered surface of said valve port further includes a trigger means operatively connected with said needle member for moving said needle member rearwardly out of contact with the tapered surface of said valve port and against said stop member.

Claim 7

An improved airless spray gun comprising: a body; a spray nozzle assembly secured to said body wherein said spray nozzle assembly includes; a passageway extending through said spray nozzle assembly having one end in communication with a source of liquid under pressure, a nozzle opening in communication with the other end of said passageway, a seat member positioned in said passageway between the ends thereof housing a tapered valve port whose tapered surface defines a seat angle, a chamber extending from said seat member to said nozzle opening, a needle member in cooperation with said tapered valve port whose tapered surface defines a needle angle, said needle angle being greater than said seat angle; and means for moving said needle member into contact and out of contact with said seat member thereby defining a closed position and an opened position of said needle member, said seat member being positioned such that the projected extension of the tapered surface of said needle member converges to a point as said nozzle opening when said needle member is in said closed position.

Claim 8

An improved airless spray gun comprising: a body; a spray nozzle assembly secured to said body wherein said spray nozzle assembly includes; a passageway extending through said spray nozzle assembly having one end in communication with a source of liquid under pressure, a nozzle opening in communication with the other end of said passageway, a seat member positioned in said passageway between the ends thereof housing a tapered valve port whose tapered surface defines a seat angle, a chamber extending from said seat member to said nozzle opening, a needle member in cooperation with said tapered valve port whose tapered surface defines a needle angle, said needle angle being greater than said seat angle; and means for moving said needle member into contact and out of contact with said seat member thereby defining a closed position and an opened position of said needle member, said seat member being positioned such that the projected extension of the tapered surface of said needle member converges to a point as said nozzle opening when said needle member is in said closed position.

Claim 9

The improved airless spray gun of claim 6 wherein said needle member has a maximum value of 30* and a minumum value of 10* and wherein said seat angle has a maximum value of 20* and a minimum value of 9*.

Claim 10

The improved airless spray gun of claim 7 wherein said needle angle is about 12* and said seat angle is about 10*.

Claim 11

An improved airless spray gun comprising: a body; a spray nozzle assembly secured to said body wherein said spray nozzle assembly includes; a passageway extending through said spray nozzle assembly having one end in communication with a source of liquid under pressure, a nozzle opening in communication with the other end of said passageway, a seat member positioned in said passageway between the ends thereof housing a tapered valve port whose tapered surface defines a seat angle, a chamber extending from said seat member to said nozzle opening, a needle member in cooperation with said tapered valve port whose tapered surface defines a needle angle; means for moving said needle member into contact and out of contact with said seat member thereby a closed position and an open position of said needle member, said seat member being positioned such that the projected extension of the tapered surface of said needle member converges to a point at said nozzle opening when said needle member is in said closed position and said seat member and said needle member defining an annular cone-shaped passageway when said needle member is in said open position which is sufficient in length to form the fluid passing therethrough into an annular cone-shaped sheet.

Claim 12

An improved airless spray gun comprising: a body; a spray nozzle assembly secured to said body wherein said spray nozzle assembly includes; a passageway extending through said spray nozzle assembly having one end in communication with a source of liquid under pressure, a nozzle opening in communication with the other end of said passageway, a seat member positioned in said passageway between the ends thereof housing a tapered valve port whose tapered surface defines a seat angle, a chamber extending from said seat member to said nozzle opening, a needle member in cooperation with said tapered valve port whose tapered surface defines a needle angle; means for moving said needle member into contact and out of contact with said seat member thereby a closed position and an open position of said needle member, said seat member being positioned such that the projected extension of the tapered surface of said needle member converges to a point at said nozzle opening when said needle member is in said closed position and said seat member and said needle member defining an annular cone-shaped passageway when said needle member is in said open position which is sufficient in length to form the fluid passing therethrough into an annular cone-shaped sheet.

Claim 13

The improved airless spray gun of claim 9 wherein said means for moving the needle member into contact and out of contact with the seat member adjustably controls the flow rate of the liquid passing through said annular cone-shaped passageway.

Claim 14

The improved airless spray gun of claim 9 wherein the length of said cone-shaped passageway is at leasT twice the diameter of said valve port.

Claim 15

The improved airless spray gun of claim 11 having an annular opening located at the entrance to said annular cone-shaped passageway wherein the cross-sectional area of said annular opening is substantially equal to the cross-sectional area of said nozzle opening.

Claim 16

The improved airless spray gun of claim 12 having means to provide for the adjustment and control of the size of the cross-sectional area of said annular opening so as to accommodate any size of nozzle opening.

Claim 17

The improved airless spray gun of claim 13 wherein said annular cone-shaped sheet impinges at said nozzle opening to generate a soft spray suitable for fine finish spraying.

Claim 18

An improved spray gun suitable for the airless spraying of liquids such as paints comprising: a body; a spray nozzle assembly secured to said body including, a nozzle opening extending through one end of said spray nozzle assembly and being elongated in cross section, a chamber in communication with said nozzle opening having a cross-sectional area at one end substantially greater than the cross-sectional area of said nozzle opening, a seat member defining one end of said chamber and containing a tapered valve port having a lateral surface which converges in the direction of said nozzle opening and defines a seat angle, and a conical member suitable for insertion into said valve port having a tapered side which converges in the direction of said nozzle opening to define a conical angle, said conical angle being greater than said seat angle, means for moving said conical member into and out of contact with said seat member thereby defining a closed position and an open position of said conical member; an entrance passageway associated with a source of liquid under pressure and in communication with said valve port; an annular cone-shaped passageway extending through said entrance passageway within said chamber to allow for the passage of said liquid through said annular cone-shaped passageway in the form of an annular cone-shaped sheet which impinges at the entrance of said nozzle opening; an annular opening at the entrance of said annular cone-shaped passageway when said conical member is in said open position having an optimum cross-sectional area substantially equal to the cross-sectional area of said nozzle opening; means to predetermine and to control the cross-sectional area of said annular opening so as to accommodate any size of said nozzle opening.

Claim 19

An improved spray gun suitable for the airless spraying of liquids such as paints comprising: a body; a spray nozzle assembly secured to said body including, a nozzle opening extending through one end of said spray nozzle assembly and being elongated in cross section, a chamber in communication with said nozzle opening having a cross-sectional area at one end substantially greater than the cross-sectional area of said nozzle opening, a seat member defining one end of said chamber and containing a tapered valve port having a lateral surface which converges in the direction of said nozzle opening and defines a seat angle, and a conical member suitable for insertion into said valve port having a tapered side which converges in the direction of said nozzle opening to define a conical angle, said conical angle being greater than said seat angle, means for moving said conical member into and out of contact with said seat member thereby defining a closed position and an open position of said conical member; an entrance passageway associated with a source of liquid under pressure and in communication with said valve port; an annular cone-shaped passageway extending through said entrance passageway within said chamber to allow for the passage of said liquid through said annular cone-shaped passageway in the form of an annular cone-shaped sheet which impinges at the entrance of said nozzle opening; an annular opening at the entrance of said annular cone-shaped passageway when said conical member is in said open position having an optimum cross-sectional area substantially equal to the cross-sectional area of said nozzle opening; means to predetermine and to control the cross-sectional area of said annular opening so as to accommodate any size of said nozzle opening.

Claim 20

An improved airless spray gun comprising: a body; a spray nozzle assembly secured to said body wherein said spray nozzle assembly includes; a passageway extending through said spray nozzle assembly having one end in communication with a source of liquid under pressure, a nozzle opening in communication with the other end of said passageway, means positioned in said passageway between the ends thereof for directing at least two portions of the liquid along converging paths so that said portions intersect at the entrance of said nozzle opening, means for adjustably controlling the flow rate of the liquid portions which intersect at said nozzle opening.

Claim 21

An improved airless spray gun comprising: a body; a spray nozzle assembly secured to said body wherein said spray nozzle assembly includes; a passageway extending through said spray nozzle assembly having one end in communication with a source of liquid under pressure, a nozzle opening in communication with the other end of said passageway, means positioned in said passageway between the ends thereof for directing at least two portions of the liquid along converging paths so that said portions intersect at the entrance of said nozzle opening, means for adjustably controlling the flow rate of the liquid portions which intersect at said nozzle opening.

Claim 22

An improved airless spray gun comprising a body with a passageway therethrough for fluid to be sprayed, means for connecting a high pressure fluid source to one portion of the passageway, a nozzle portion having a spray opening communicating with said passageway, and a valve assembly in said passageway close to said spray opening, said valve assembly comprising a valve body portion having a valve seat opening therein and a needle valve portion movable axially within said valve seat opening between a closed position in which the needle valve portion closes the valve seat opening and passageway and a restricted open position providing for accelerated linear movement of fluid from said passageway through said valve seat opening to said spray opening, at least one of said valve body and needle valve portions having a surface guiding the fluid into a thin annular sheet converging to an apex at said spray opening.

Claim 23

An improved airless spray gun comprising a body with a passageway therethrough for fluid to be sprayed, means for connecting a high pressure fluid source to one portion of the passageway, a nozzle portion having a spray opening communicating with said passageway, and a valve assembly in said passageway close to said spray opening, said valve assembly comprising a valve body portion having a valve seat opening therein and a needle valve portion movable axially within said valve seat opening between a closed position in which the needle valve portion closes the valve seat opening and passageway and a restricted open position providing for accelerated linear movement of fluid from said passageway through said valve seat opening to said spray opening, at least one of said valve body and needle valve portions having a surface guiding the fluid into a thin annular sheet converging to an apex at said spray opening.

Claim 24

A spray gun according to claim 17 in which said valve body portion and needle valve member have cooperating axially extending conical surfaces providing an annular conical passageway therebetween when the valve member is in open position, at least one of said conical surfaces converging toward a vertex at said spray opening and the conical surface of at least said needle valve member terminating at a point spaced axially from said spray opening thereby providing a region of fluid turbulence between the spray opening and the annular conical valve passageway, aid region being located within a conical area defined by the projection of said surface of the valve body toward said spray opening.