JPS6233574A - Lance type three-nozzles spray device - Google Patents

Abstract

PURPOSE:To eliminate the problem of paint drop-out, etc., with a lance type painting spray having a body gun and end gun for the inside surface of a vessel by providing a spray nozzle for end and stream nozzle for crevasse to the end gun. CONSTITUTION:A branch path is provided to the paint flow passage of a nozzle tip body of the end gun 3 of the lance type paint spray device having the body gun 2 and the end gun 3 for the inside surface of the vessel. The spray nozzle 8 for end is provided to the top end of the flow passage and the stream nozzle 9 for crevasse is provided to the front end of the above-mentioned branch passage. As a result, the crevasse part is directly painted by the paint jet; therefore, the problem such as paint drop-out is eliminated even in a line where the time to arrive at a drying furnace after painting is short. There is no need for spraying the excessive paint to the vessel body and end part, by which the paint is economized and the generation of bridges and blisters is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a spray device for painting the inner surface of a can, and particularly to a three-nozzle spray device provided with nozzles for painting the crevasse portion.

(Prior art) During the can manufacturing process, the coating on the inner surface of a can is instantaneously stopped in a fixed position.
This is done by inserting two spray guns, one for the can body and one for the can end, into an empty can that is rotating at high speed, and spraying paint.

In this coating method, coating the crevices that occur around the rim of the bottom of a 3-piece can can be done either by excessive paint applied on the end flowing into the crevasse due to centrifugal force, or by
A method is used in which the excess paint applied to the can body is allowed to drip down naturally at the Royal Station during transportation.

For this reason, the coating of crevasse areas is greatly influenced not only by spray conditions, but also by transportation conditions and drying conditions.

Depending on the conditions, there have been problems such as paint omission where the paint is not painted, bridges where a paint film is formed in the shape of a bridge over crevasses, or blisters where excess paint foams in a caramel shape.

Furthermore, in neck-in cans in which the diameter of the can body is reduced near the seam, there has been a problem in that paint tends to accumulate in a portion of the neck shoulder where the diameter has been reduced, and it is difficult for the paint to naturally flow down into the crevasse.

To reliably paint this crevasse, the can body, end,
It is desirable to spray each crevasse with a separate nozzle. However, in the above device called the lance type, there are two guns that can be inserted into the can body: one for the end and one for the body.
The book was the limit, and 3 guns was considered impossible.

In response to this, the present inventors first provided a branching path in the paint flow path of the nozzle tip body of the end gun, provided an end nozzle at the tip of the flow path, provided a crevasse nozzle at the tip of the branched path, and provided the paint flow path to the end gun. We proposed a spray device that directly sprays and paints the crevasse area using a dedicated nozzle. (Japanese Patent Application No. 59-22831) Although this device has two guns inserted into the can body, one for the end and one for the body, it improves the coating of the crevasse area, greatly reducing the coating defects of the conventional device, and making it easier to use. This has the great effect of saving paint as well.

(Problems to be solved by this invention) However, 1. For example, when the speed of the production line is high, such as when manufacturing cans with a small height, the time from finishing painting to reaching the drying oven is short, and the paint does not reach the crevasse. It will not be possible to flow down sufficiently. If the amount of spray is increased to increase the flow rate, problems similar to those of conventional devices will occur.

Structure of the Invention (Means for Solving Problems) The three-nozzle spray device of the present invention is a lance-type coating spray device for the inner surface of a can having a body gun and an end gun, in which a three-nozzle spray device branches into a paint flow path in a nozzle tip body of the end gun. A channel is provided, an end spray nozzle is provided at the tip of the flow path, and a crevasse stream nozzle is provided at the tip of the branch path.

(Function) Spraying from a nozzle is an extremely excellent method for uniformly applying paint within a certain area, but since the mist droplets are spread out and distributed, it is impossible to concentrate on one specific point. do not have. For this reason, when the crevasse nozzle is a spray nozzle, paint adheres to the body portion and end portion near the crevasse, and this paint flows into the crevasse. Therefore, if the time for the inflow is insufficient, the above-mentioned drawbacks will occur.

On the other hand, if the paint from the crevasse nozzle is in the form of a jet rather than a mist, it is much easier to concentrate this stream. Therefore, by directing the paint stream toward the crevasse, the crevasse can be directly coated, which not only ensures reliable coating, but also avoids unnecessary coating around the crevasse.

(Embodiment) Fig. 1 is a conceptual diagram of a lance-type spray gun of the present invention, in which the spray gun inserted into an empty can 1 has a body gun 2 having a nozzle that sprays paint at a certain angle to the axis of the spray gun. and an end gun 3 having a nozzle that sprays paint in the axial direction. As the cross section of the nozzle tip body 3' at the tip of the end gun 3 is shown in FIG. The branch leads to the nozzle 9. This nozzle 9 is a stream injection nozzle that has a minute injection hole of approximately 0°1 ms+diameter at its tip and aims directly at the crevasse portion 5.

This stream is arranged so as to be directly injected into the crevasse of the can 1, so that the amount of coating on the shoulder portion 4 and end portion 6 in the vicinity thereof is much smaller than in the past.

Effects of the Invention Since this invention has the above-mentioned configuration, the paint pass portion is directly painted by the paint jet, so even if the line takes a short time to reach the paint drying oven, problems such as paint waves do not occur. In addition, there is no need to spray excessive amounts of paint onto the body or end of a can, resulting in remarkable effects such as saving paint and preventing the occurrence of bridges and blisters.

BRIEF DESCRIPTION OF THE DRAWINGS The figure is a conceptual diagram of the lance-type spray gun of the present invention, and FIG. 2 is a sectional view of one embodiment of the nozzle tip body. 1: Can body 2: Body gun 3: End gun 5: Crevasse 8: End nozzle 9: Crevasse nozzle

Claims (1)

[Claims] In a lance-type spray device for painting the inside of a can that has a body gun and an end gun, a branching path is provided in the paint flow path of the nozzle tip body of the end gun, and a spray nozzle for the end is installed at the tip of the flow path, and a spray nozzle for the crevasse is installed at the tip of the branching path. A lance-type three-nozzle spray device characterized by being equipped with a stream nozzle.