JPH0688005B2 - Spray gun for painting - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention provides a fan-shaped spray flow suitable for coating by supplying an air flow from the periphery to a fan-shaped spray ejected from an orifice type flat spray nozzle. It relates to a spray gun that is designed to generate.

(Problems of the prior art) Various spraying devices have been announced in which an air flow is added to the fan-shaped spray from an orifice type flat-spraying liquid jet nozzle from the surroundings. 57-
There are those described in Japanese Patent No. 90762 and Japanese Patent Application Laid-Open No. 50-53430.

The prior art described in Japanese Utility Model Laid-Open No. 57-90762 is also provided under the condition that a lip-shaped jet nozzle formed by the intersection of a dome-shaped concave hole and a groove is crowned on a flat spray nozzle. Therefore, the fan-shaped spray ejected from the jet nozzle in the fan-shaped air flow is ejected in a common plane relationship to improve atomization and prevent mist scattering. Tail generation prevention effect, mist scattering prevention effect, spray flow disturbance prevention effect, etc. are recognized, but it is especially sufficient for finish coating of highly adhesive paints that tend to generate tails, metallic paints that tend to cause spots on the coating I was not satisfied.

Further, the prior art described in Japanese Patent Application Laid-Open No. 50-53430 supplies a fan-shaped spray ejected from a flat spray jet nozzle with a hollow conical air stream that gradually narrows from the rear to the front. It is designed to supply an obliquely forward airflow to both sides of the hollow conical air film by maintaining the balance of the hollow conical air film and from both sides. Since it is difficult to maintain the balance of the air flow of the fan-shaped spray flow, the fan-shaped spray flow is partially shaded, and a turbulent phenomenon of swinging under the line is likely to occur,
There is a serious defect that causes uneven painting.

(Object of the Present Invention) The present invention not only further improves the atomization effect, the tail generation prevention effect, the mist scattering prevention effect, the spray flow disturbance prevention effect, etc., but also flattens the spray without impairing these various effects. It is an object of the present invention to provide a spray gun for painting, which can improve coating efficiency and efficiently coat a wide range.

(Characteristics of the present invention) In order to achieve the above object, the present invention is arranged such that the jet nozzle member is capped on an orifice type flat spray nozzle, and the jet nozzle member is a lip for ejecting a fan-shaped airflow. -Shaped flat blown jet liquid nozzle, and the orifice-type flat-blown jet liquid nozzle is provided with a lip-shaped jetted liquid nozzle. In addition, the fan ejecting from the lip-shaped jet nozzle is arranged so that the long axis of the lip-shaped jet nozzle of the jet nozzle and the long axis of the lip-shaped opening of the jet nozzle have a cross shape. The atomized spray and the fan-shaped airflow ejected from the lip-shaped opening in the fumarolic nozzle are ejected in a cross-shaped cross section under a common axis, which results in a fan-shaped angle of the fan-shaped atomized ejected from the lip-shaped ejection port. To It is narrowed and propelled in a conical tendency, and further, protrusions are provided on both sides, which are appropriately separated in the long axis direction from the lip-shaped opening of the jet nozzle.
The pair of fumarolic nozzles are provided obliquely forward under the condition that they are directed to the front near the outside of the minor axis end of the lip-shaped opening in the fumarolic nozzle and are gradually expanded with the adjacent nozzles. Of the air blown from each of the above-mentioned conical nozzles are caused to collide with each other near both ends near the base of the fan-shaped spray jetted from the orifice type flat-spraying liquid nozzle, and a pair of fan-shaped air flows generated by this collision cause the cone This is characterized in that the fan-shaped spray propelled in a tendency to be turned toward is outwardly directed to widen the spray angle of the fan-shaped spray.

(Example) Hereinafter, the example which shows the coating spray gun of this invention in drawing is demonstrated in detail.

As shown in FIGS. 1 to 3, the spray gun body 1
The valve seat 2 is fixed to the central portion of the spray gun main body 1 through which the needle valve 3 corresponding to the valve seat 2 is provided so as to move back and forth. The paint which is pressure-fed from the rear of the spray gun can be fed from the valve seat 2 to the front by retreating the needle valve 3, and at the front end of the spray gun body 1 there is a lip-shaped jet 5c. A holder 6 having a flat-blowing jet nozzle 5 fixed to the tip is provided oppositely with an interposition of a packing 7, and a jet nozzle 8 having a jet nozzle 8 having a lip-shaped opening 8a on the outer peripheral side of the holder 6. The member 9 has the same axial line relationship as that of the orifice type flat-spraying liquid nozzle 5, and the long axis of the lip-shaped liquid jet port 5c and the long axis of the lip-shaped opening 8a have a vertical and horizontal cross shape. With the nut 10 sprayed while mated The holder 6 and the spray gun body 1 are provided with ventilation passages 11 and 12 so as to communicate with the jet nozzle 8 respectively.
While supplying pressurized air supplied from the rear from both ventilation passages 12 and 11 to the fumarolic nozzle 8, a fan-shaped air flow is ejected from the fumarolic nozzle 8, and the fan-shaped air flow causes the flat-blowing liquid jet nozzle 5 to eject. The spraying fan-shaped paint spray is made to be conical, in other words, has a tendency to have a circular elliptical cross section, and the spray nozzle member 9 is further provided with a lip-shaped opening 8a of the spray nozzle 8. Protrusions 13 and 13 are provided on both sides which are appropriately separated in the longitudinal direction, and two pairs of jet nozzles 14 and 14 are provided inside the protrusions 13 and 13 to form the lip-shaped opening 8
Under the condition of directing to the front near the outside of the short axis end of a, it is provided in a state of being slightly obliquely forward and gradually expanding forward with the adjacent nozzles, whereby the orifice type flat spray nozzle 5 Of the fan-shaped spray ejected from the vicinity of both ends near the base, the air streams ejected from the fumarolic nozzles 14 and 14 can be made to collide with each other, and the vent nozzles 14 and 14 communicate with them. In addition to installing 15 and 15 in the rearward direction, the spray gun body 1 is also provided with an air passage 16 that communicates with the air passage 15, so that pressurized air supplied from the rear is supplied from the air passages 16 and 15 to the fumarolic nozzles 14 and 14. At the same time, the air flow ejected from the fumes nozzles 14 and 14 was jetted with a tendency to collide with the counter air flow diagonally forward, and collided at the outer side near both end edges near the base of the fan-shaped spray. rear,
The confluence flattens the particles and propels them obliquely forward to the outside, thereby enlarging the fan-shaped spray having a conical tendency toward the outside to widen the fan-shaped angle.

As the orifice type flat-spraying jet nozzle 5, as shown in FIGS. 7 to 9, for example, a recessed hole 5a having a dome-shaped terminal portion and a rear open state is provided in a short cylindrical nozzle member, and a front end is provided. A groove 5b having a V-shaped cross section is provided in the portion so as to intersect with the end portion of the recessed hole 5a, and a lip-shaped jet port 5c is opened.

In addition to the above, in order to further flatten the spray and widen the fan-shaped angle, the flattening fumes directed obliquely forward and toward the axis of the jet nozzle 5 are located in the middle of the fusible nozzles 14, 14 in the projecting portion 13. The nozzles 17 and 18 are provided under a state in which a proper distance is maintained in the front and rear, and the air passage 1 communicating with both the flattening fumarolic nozzles 17 and 18 and the air passage 16 is provided.
It is preferable to provide 9 to eject the air flow toward the central portion of the fan-shaped spray toward the base, and the flattening fumes nozzles 17 and 18 are used before the jet air flow collides with the spray. It is preferable that the flat flows are formed by colliding with each other in an acute angle relationship, and the flat flow is supplied along the side surface of the fan-shaped spray from obliquely rearward.

By using the electrostatic coating method in combination with the present invention, it is possible to improve atomization and coating efficiency. In the embodiment shown in FIGS. 1 to 3, Conductive wires 20 and 21 penetrating the spray gun main body 1 and the squirt nozzle member 9 are provided under the interposition of a contact part in the middle, and the tip of the conductive wire 21 is used as a needle electrode 22. It is arranged obliquely inward from a portion near the tip of the projecting portion 13 and is disposed near the base surface of the fan-shaped spray.
By applying a high voltage through the conductive wires 20 and 21, the fan-shaped spray is charged with a high voltage.

Further, in the embodiment shown in FIG. 4, instead of the needle-shaped electrode 22 described in the embodiment in FIGS. 1 to 3, the jet nozzle 5 itself is made of conductive cemented carbide and applied to the electrode. In addition to forming the tip sharp, the holder 6 is made of metal so that the portion near the tip of the conductive wire 21 is brought into contact with the holder 6, and other configurations are the same in nature as in the above embodiment. For this reason, the same parts are designated by the same reference numerals and the description thereof will be omitted.

As for the lip-shaped fumarole 8a provided in the fumarolic nozzle member 9, as shown in FIGS. 1 to 3, a dome-shaped concave hole 25 is provided in the rear open state in the center near the front end, and the front end has a rounded bottom. By intersecting a certain V-shaped groove 26 with the dome-shaped recessed hole 25 to an appropriate depth and performing conical counterbore from the outside on the same axis, both inner portions in the minor axis direction are formed. It is desirable to provide arcuate notches 27, 27,
Further, in order to strengthen the conicalization of the fan-shaped spray, obliquely inward blowout ports 28, 28 may be provided outside the arcuate notch 27 in the lip-shaped opening 8a.

In addition, as shown in FIG. 5 and FIG. 6, the squirting nozzle 8 may have relatively thin and deep notches 27, 27 provided at both inner sides of the lip-shaped opening 8a in the minor axis direction. Often, in manufacturing, as in the formation of the lip-shaped opening 8a, the V-shaped groove 26 'having a rounded bottom is crossed with the V-shaped groove 26 in a cross shape, and the dome shape is formed. While intersecting with the recessed hole 25 to an appropriate depth, thereby ejecting a fan-shaped airflow having a cross-shaped cross section in the center, one fan-shaped airflow, that is, a lip-shaped opening 8a.
The fan-shaped airflow ejected from the fan attracts the central plane portion of the fan-shaped spray to both sides, and at the same time, the fan-shaped airflow ejected from the other fan-shaped airflow, i.e., the notches 27, 27 prevents the occurrence of tails. It is designed to exert the effect of preventing spray scattering.

With the above configuration, when using it, the supply pressure of the paint is several to 150 kg / cm ^2, and the supply pressure of air is several kg / cm.
It is selected to be ² or less, and it is possible to adapt to a wide range of low-viscosity to high-viscosity paints and other paints having various properties by selecting the supply pressures thereof.

(Effect) As described above, according to the present invention, the jet nozzle 8 having the lip-shaped opening 8a for jetting the fan-shaped air flow is provided, and the jet nozzle 8 is the same as the outer peripheral portion of the orifice type flat spray nozzle 5. In addition to the axial relationship, the lip-shaped jet port 5c and the long axis of the lip-shaped jet port 8a are arranged so that the long axis of the lip-shaped jet port 5c has a cross shape, and jetted from the lip-shaped jet port 5c. By making the fan-shaped spray and the fan-shaped air flow ejected from the lip-shaped fumarole 8a eject in a cross-shaped cross section under the common axis,
While concentrating the flat portion of the fan-shaped spray toward the both sides, and tending to push the end-edge portion of the fan-shaped spray toward the center, the fan-shaped spray is once conical in the propulsion process, Moreover, two pairs of jet nozzles 14 and 14 are provided on both sides of the lip-shaped opening 8a, which are appropriately separated in the longitudinal direction, and the air flow ejected from the jet nozzles 14 and 14 is the orifice-type jet nozzle 5. So that they collide with each other near both edges near the base of the fan-shaped spray ejected from
As a result, the fan-shaped spray that tends to be conical is crushed from both sides, and is attracted toward the edge to widen the angle.Since such fan-shaped spray is once conical and then fanned, it is atomized. The effect of preventing tail generation and the effect of preventing turbulence of the spray flow are significantly improved without sacrificing the effect and mist scattering prevention effect, and at the same time uniform atomization is realized, which results in a uniform coating film with no unevenness. It can be easily formed, especially when using a metallic paint that is likely to cause subtle mottle on the coating film, it is possible to finish coating without causing mottle,
In addition, the fan-shaped spray can be widened without causing the so-called hollow-out phenomenon in which the central portion of the spray is reduced while exhibiting the above-described effects, so that the efficiency of the coating work can be realized.

[Brief description of drawings]

1 to 3 show a main part of a coating spray gun of the present invention in one embodiment. FIG. 1 is a vertical sectional side view, FIG. 2 is a partially broken front view, and FIG. FIG. 4 is a cross-sectional plan view, FIG. 4 is a cross-sectional plan view of only essential parts in another embodiment, and FIGS. 5 and 6 are vertical side views and front views of only fumarolic nozzles in still another embodiment. FIG. 7 is an enlarged vertical side view of only the orifice type flat spray nozzle, FIG. 8 is a front view of the nozzle, and FIG. 9 is a cross-sectional plan view of the nozzle. 1-Spray gun body 5-Orifice type flat-blown jet liquid nozzle 5a-Concave hole 5b-Groove 5c-Lip-shaped jet port 6-Holder 8--Fume nozzle 8a-Lip-shaped opening 9 ...... Fume nozzle member 13 ...... Projection part 14 ...... Fume nozzle 21 ...... Dome shape concave hole

Claims (1)

[Claims] 1. A nozzle member is provided with a recessed hole (5a) having a dome-shaped end portion in a rear open state, and a groove (5b) having a V-shaped cross section is provided at a front end portion of the recessed hole (5a). An orifice type flat-blowing jet nozzle (5) of a type in which a lip-shaped jet port (5c) is provided so as to intersect the portion is adopted, and this orifice-type flat-blowing jet nozzle (5) is attached to a holder (6). ) Is attached to the front end of the spray gun main body (1), and a fumarolic nozzle member (9) is provided separately, and a dome-shaped recess is formed in the central portion of the fumarolic nozzle member (9) near the front end. While forming the hole (21) in the rear open state,
At the front end of the dome-shaped concave hole (21), an air-jet nozzle (8) having a fan-shaped airflow jet lip-shaped opening (8a) is opened, and the air-jet nozzle member (9) uses the orifice type flat-blown jet. The relationship between the liquid nozzle (5) and the long axis of the lip-shaped jet (5c) and the long axis of the lip-shaped opening (8a) has a cross shape in the same axial relationship. Attached to the front end of the spray gun body (1) in a closed state, the fan-shaped spray and the lip-shaped opening (8a) ejected from the lip-shaped jet port (5c)
And a fan-shaped air flow ejected from the jet nozzle have a cruciform cross section under a common axis, and the jet nozzle member (9) is appropriately separated from the lip-shaped opening (8a) in the longitudinal direction. Protrusions (13) and (13) are provided on both sides, and two pairs of jet nozzles (1) are provided inside the protrusions (13) and (13).
4) and (14) are provided obliquely forward while being directed outward near the short axis end of the lip-shaped opening (8a) and gradually expanding with the adjacent nozzles. The airflows ejected from the nozzles (14) and (14) in opposite directions can be made to collide with each other in the vicinity of both end edges of the fan-shaped atomization base ejected from the orifice type flat spray liquid nozzle (5). Spray gun for painting.