Coating nozzle and coating apparatus
A coating nozzle includes: a nozzle hole from which a liquid paint is discharged in a liquid discharge direction; a liquid chamber communicating with the nozzle hole; a paint supply channel communicating with the liquid chamber, the paint supply channel configured to supply the liquid paint to the liquid chamber, a cleaning-liquid supply channel communicating with the liquid chamber, the cleaning-liquid supply channel configured to supply a cleaning liquid to the liquid chamber; and a switching section configured to selectively switch communication and non-communication between the paint supply channel and the liquid chamber.
1 . A coating nozzle comprising:
a nozzle hole from which a liquid paint is discharged in a liquid discharge direction;
a liquid chamber communicating with the nozzle hole;
a paint supply channel communicating with the liquid chamber, the paint supply channel configured to supply the liquid paint to the liquid chamber;
a cleaning-liquid supply channel communicating with the liquid chamber, the cleaning-liquid supply channel configured to supply a cleaning liquid to the liquid chamber; and
a needle valve configured to selectively switch communication and non-communication between the paint supply channel and the liquid chamber,
wherein the cleaning-liquid supply channel is configured to supply the cleaning liquid in a region between a closed tip of the needle valve and the nozzle hole, independently from the paint supply channel supplying the liquid paint to the liquid chamber, and while supplying of the liquid paint by the paint supply channel is stopped, and
the paint supply channel is configured to supply the liquid paint to the liquid chamber while supplying of the cleaning liquid by the cleaning-liquid supply channel is stopped.
2 . The coating nozzle according to claim 1 , further comprising:
a body including:
the paint supply channel;
the cleaning-liquid supply channel; and
the needle valve; and
a nozzle part including:
the liquid chamber; and
the nozzle hole,
wherein the nozzle part is attachable to or detachable from the body.
3 . The coating nozzle according to claim 1 ,
wherein the liquid chamber has:
a first inlet at which the paint supply channel is connected to the liquid chamber; and
a second inlet at which the cleaning-liquid supply channel is connected to the liquid chamber, and
the second inlet is closer to the nozzle hole than the first inlet in the liquid discharge direction.
4 . The coating nozzle according to claim 3 ,
wherein the needle valve openably closes the first inlet.
5 . The coating nozzle according to claim 4 , further comprising:
a driver in an accommodating space, the driver configured to drive the needle valve; and
a blocker attached to the needle valve, the blocker configured to block the liquid paint in the paint supply channel from entering the accommodating space.
6 . The coating nozzle according to claim 5 ,
wherein the driver electromagnetically, pneumatically, or piezoelectrically drives the needle valve.
7 . The coating nozzle according to claim 5 ,
wherein the blocker is resistant to a solvent contained in the liquid paint or the cleaning liquid.
8 . The coating nozzle according to claim 1 ,
wherein the nozzle hole has:
a minimum opening dimension of 20 μm or more; and
a maximum opening dimension of 500 μm or less.
9 . The coating nozzle according to claim 1 ,
wherein the paint supply channel includes a circulation channel, from which the liquid paint is discharged, to circulate the liquid paint.
10 . The coating nozzle according to claim 1 ,
wherein the first inlet is in a vicinity of the second inlet,
the needle valve having a leading end to close the first inlet at a closed position, and
the leading end of the needle valve at the closed position protrudes into an interior of the liquid chamber from the first inlet.
11 . The coating nozzle according to claim 10 ,
wherein the cleaning liquid supplied from the cleaning-liquid supply channel is supplied from the second inlet to the liquid chamber in a state where the needle valve closes the first inlet.
12 . A coating apparatus comprising:
the coating nozzle according to claim 1 ; and
a slider including an axis to which the coating nozzle is attached, the slider configured to move the coating nozzle in an axial direction of the axis.
13 . The coating apparatus according to claim 12 , further comprising:
a rotator configured to rotate an object,
wherein the coating nozzle is configured to discharge the liquid paint to the object rotated by the rotator to coat the object with the liquid paint.