JP3032920B2 - Inner / outer surface treatment method and apparatus for bottomed can body - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for treating the inner and outer surfaces of a bottomed can body and an apparatus used therefor. Furthermore, the present invention, in a surface treatment tank provided with a plurality of treatment liquid application sections, by an endless belt conveyor having a structure capable of passing gas and liquid, transporting the bottomed can body upside down, A method and apparatus for minimizing the amount of processing liquid adhering to a can body when treating the inner and outer surfaces of the can body by spraying a predetermined processing solution onto the can body from above and below. About.

[0002]

2. Description of the Related Art Among the bottomed can bodies, DI cans having the highest production volume (hereinafter sometimes simply referred to as cans) are usually prepared by first punching a lubricated metal coil into a circular shape, and then drawing and processing. After forming a cup-shaped molded body by re-drawing, then squeezing the molded body while spraying lubricating oil, forming the bottom, and then trimming the opening side to adjust the can height The shape is completed. After such work, the can body is subjected to a degreasing treatment to remove the lubricating oil adhering to the surface of the can, a chemical treatment to improve the adhesion with ink and paint, and a water washing treatment to wash out the chemical liquid. It is common to receive.

[0003] As this surface treatment method, for example, as described in Japanese Patent Application Laid-Open No. 50-77440 and US Pat. No. 3,262,460, a DI can is inverted on a metal net-shaped belt conveyor. Placing, i.e., placing the can opening end down, while transporting horizontally in the surface treatment tank,
Each treatment liquid spraying station (station) in the tank was previously disposed above and below the conveyor, and from the lower spray nozzle, degreasing liquid, industrial water, chemical liquid, industrial water, and deionized water were supplied. Most commonly, the inner and outer surfaces of the can are degreased, converted, and washed by spraying the can body one after another.

As described above, the conveyor for carrying the can body is a net-shaped conveyor and has a large amount of space, so that the processing liquid sprayed onto the can body from above and below naturally flows down through the conveyer. . A processing liquid storage tank is provided below the lower spray nozzle of each processing station to receive the flowing processing liquid, and the processing liquid in these tanks is pumped up and repeatedly used for reuse of each processing liquid. To the upper and lower spray nozzles.

Further, at the end portion of each processing station, instead of the upper spray nozzle, the processing liquid stored at the bottom of the can (the bottom of the inverted can has a concave portion which is recessed toward the open end of the can, so An air injection nozzle for blowing off the processing liquid in the recess is disposed slightly downward above the DI can passing therethrough.

In the conventional apparatus having such a configuration, the DI can placed upside down on a belt conveyor passes through a degreasing treatment station in which a degreasing liquid is sprayed from above and below a conveying path of the can. The lubricating oil adhering to the inner and outer surfaces is washed away, and then passes under the air injection nozzle to blow off the degreasing liquid accumulated at the bottom of the can, and then to the next washing station. enter.

In this processing station, the degreasing liquid adhering to the inner and outer surfaces of the can is washed away by water sprayed from a spray nozzle disposed above and below the conveying path of the can, and then the can is removed. The treated water accumulated at the bottom is blown off by the pressurized air from the air injection nozzle.

[0008] The same treatment is performed in the subsequent chemical conversion treatment station, secondary washing treatment station, and deionized washing treatment station.

Thus, the processing liquid accumulated at the bottom of the can is blown off (blow-off) near the end of each processing station (the blown processing liquid falls into the lower tank). (The sum of the amount of the processing liquid adhering to the surface of the can and the amount of the processing liquid adhering to the conveyor) can be reduced, and as a result, the consumption of the processing liquid can be reduced. To reduce the speed of contamination (or dilution) of the processing solution in the next processing station by bringing the processing solution from the previous processing station to the next processing station, in other words, the life of the processing solution. Can be extended.

[0010]

[Problems to be solved] However, as a measure to reduce the production cost of bottomed cans, the amount of the processing liquid that adheres to the surface of the can (including the open end) and is taken out to the next processing station is still reduced. It is desired to further reduce.

In this case, what can be easily considered is to increase the pressure of the air jetted from the air jet nozzle to force the treatment liquid adhering to the surface of the can to flow down.

However, since the normal DI can has a higher can height than the can diameter and the bottom wall is about three times as thick as the body wall, the center of gravity is considerably high, and the center of gravity is strong (high speed). When the airflow is received, there is a strong possibility that the airbag loses balance and falls over. In practice, there is a limit in increasing the injection air pressure, and it is difficult to implement the method.

Further, the processing liquid remaining on the bottom of the can is only blown off, and the processing liquid adhering to the surface of the can is allowed to flow naturally. Although it is conceivable to increase the length, the time and equipment required for surface treatment are considerably long, and the installation space is also widened.

An object of the present invention is to provide a method and apparatus for treating the surface of a bottomed can body which has solved the above problems.

[0015]

Means for Solving the Problems In order to solve the above problems, the method of the present invention comprises the steps of:
An endless belt conveyor capable of passing gas and liquid, the bottomed can body is placed upside down and conveyed in the horizontal direction, and in each processing solution application step, a predetermined processing liquid is sprayed from above and below the can body. A method of treating the inner and outer surfaces of the can body, wherein, in at least one treatment liquid application step, pressurized air is sprayed from above onto the bottom of the can body after the treatment liquid has been sprayed. And a step of sucking the processing liquid stored and adhered to the opening end of the can body from below is added.

Further, in order to carry out the above method, the apparatus of the present invention comprises a surface treatment tank provided with a plurality of treatment liquid application sections, and a canned bottomed body placed in an inverted position in the surface treatment tank in a horizontal direction. An endless belt conveyor capable of passing gas and liquid with a transfer section for transferring, wherein each processing liquid application section is provided above and below the transfer section of the belt conveyor and is a group of spraying the same processing liquid. Upper and lower spray nozzles, and above the group,
A processing liquid storage tank disposed below the lower spray nozzle, and a means for supplying the processing liquid in the processing liquid storage tank to the lower and upper spray nozzles of the group, In the outer surface treatment device, in at least one treatment liquid application section, the air jet nozzle is disposed downward above the belt conveyor in the traveling direction of the belt conveyor ahead of the location of the upper and lower spray nozzle groups. Arranged for
The suction nozzle is disposed below the belt conveyor so as to face upward.

It is preferable that the air injection nozzle and the suction nozzle are arranged at positions facing each other with the belt conveyor therebetween.

Further, the suction nozzle may be provided at a position facing the air jet nozzle with the belt conveyor interposed therebetween, and at a position further forward than the position in the traveling direction of the belt conveyor.

In this case, it is preferable that the distance between the suction nozzle and the opening end of the can body is 5 mm or less.

Further, it is preferable to provide a processing liquid recovery tank communicating with the suction nozzle and to provide a pump and a piping system for returning the processing liquid in the processing liquid recovery tank to the processing liquid storage tank.

In general, the treatment liquid application section is composed of stations for degreasing, primary rinsing, chemical conversion, secondary rinsing and deionized water.

[0022]

According to the method and the apparatus of the present invention, in at least one processing station, a predetermined processing liquid is sprayed from above and below toward a bottomed can body mounted and conveyed on a belt conveyor in an inverted state. Thereafter, while pressurized air is blown from above toward the bottom of the bottomed can body to blow off the processing liquid accumulated at the bottom, the processing liquid attached to the opening end of the bottomed can body is sucked downward. Therefore, not only the processing liquid adhering to the opening end is sucked, but also the flow speed of the processing liquid adhering to the inner surface and the outer surface of the body is increased by this suction. Therefore, the amount of the processing liquid adhering to the bottomed can body when moving to the next processing station is significantly reduced.

Further, in the method and the apparatus of the present invention, since the pressurized air is blown from above the bottomed can body and is suctioned from below the bottomed can body, the air smoothly flows from above to below. The inverted state of the bottomed can body on the belt conveyor is stabilized.

Further, in the apparatus of the present invention, since the suction nozzle is disposed below the belt conveyor, the processing liquid adhering to the belt conveyor is also sucked, and the processing liquid is taken out to the next processing station. The amount is even smaller.

When the air injection nozzle and the suction nozzle are arranged at positions facing each other with the belt conveyor interposed therebetween, the flow of air from above to below becomes straight, so that the bottomed can body can be stabilized on the belt conveyor. The nature is further enhanced.

Further, when the suction nozzle is disposed at a position facing the air jet nozzle with the belt conveyor interposed therebetween and at a position forward of this position in the traveling direction of the belt conveyor,
The amount of the processing liquid adhering to the bottomed can body and the belt conveyor can be further reduced.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An example of the method of the present invention will be described below with reference to the drawings together with an example of the apparatus.

FIG. 1 is a schematic plan view showing a surface treatment apparatus for a can body with a bottom used in the present embodiment, FIG. 2 is a sectional side view taken along the line II-II of FIG. 1, and FIG. FIG. 4 is an explanatory view showing a main part of a suction nozzle, FIG. 5 is a plan view showing a part of a belt conveyor used in this example, and FIG.
It is -B sectional drawing.

In FIG. 1, reference numeral 1 denotes an entire surface treatment tank surrounded by a housing so that each treatment step can be performed continuously. Reference numeral 1A denotes a pre-cleaning zone, and a degreasing treatment station 1A.
1 and the first washing station 1A2, 1B
Is a chemical conversion treatment zone, which is composed of a chemical treatment station 1B1, and 1C is a post-washing zone, which is composed of a secondary washing treatment station 1C1 and a deionized water treatment station 1C2.

In each of the above zones, DI cans (hereinafter abbreviated as cans) 2, 2,...
An endless belt conveyer 10 capable of passing gas and liquid for transporting with b facing upward is provided. Each of these cans has just been trimmed to a predetermined can height.

The can 2 placed upside down on the belt conveyor 10 travels in the direction of arrow Y from the upstream 101 to the downstream 102 of the belt conveyor 10, and passes through the pretreatment zone while passing through the surface treatment tank 1. Degreasing with 1A, primary washing process,
Chemical conversion treatment in chemical conversion treatment zone 1B, post-washing zone 1C
Is subjected to a second washing deionized water treatment. Then, it is dried in a hot air drying furnace (not shown).

At each processing station, a lower spray nozzle group and an upper spray nozzle group for spraying a predetermined processing liquid onto the can are provided below and above the belt conveyor 10, respectively.

More specifically, FIG. 3 shows a lower side 3 extending below the conveyor belt 10a of the belt conveyor 10 in the belt width direction (a direction orthogonal to the traveling direction of the belt) with the same length as the belt width. Reference numeral 5 denotes a nozzle tube, and reference numeral 5 denotes a can 2 so as to face the lower nozzle tube 3 with the transport side belt 10a interposed therebetween.
Is an upper nozzle tube extending in the belt width direction at a length substantially equal to the belt width above. A plurality of pairs of upper and lower nozzle tubes 3, 5 are provided in each processing station at predetermined intervals in the belt traveling direction. These upper and lower nozzle tubes 3,
5, one end 3a, 5a is closed, and the other end 3b, 5b is connected to a degreasing liquid tank 1A3 (a processing liquid tank is different for each processing station). The processing liquid sprayed from the lower spray nozzle 4 and the upper spray nozzle 6 to the can 2 via the nozzle pipes 3 and 5 and flowing down from the can surface returns to the tank 1A3 again.

Each of these spray nozzles is a well-known spray nozzle, and the lower spray nozzle 4 is provided on the upper surface of the tube wall of the lower nozzle tube 3 immediately below the can 2 passing therethrough (in the can body transport section [described later]). (The center of the row of cans), and the upper nozzle pipe 5 facing the lower spray nozzle 4.
The upper spray nozzle 6 is attached to the lower surface of the tube wall at a position corresponding to the position directly above the can 2 passing therethrough. Each nozzle pipe is provided with a flow control valve, and each nozzle pipe can be independently adjusted in pressure.

7 and 7 '(FIG. 3) are provided on the lower surface of the upper wall of the upper nozzle tube 5 with the upper spray nozzle 6 interposed therebetween at the symmetrical positions of the row of cans conveyed on each conveying section. It is a side spray nozzle mounted obliquely above the top surface of the can and at an interval not less than the can diameter and on the same straight line as the nozzle 6, and liquid is supplied from the upper nozzle pipe 5. These side spray nozzles are effective for preventing contact between the front and rear cans.

As shown in FIGS. 2 and 4, the can 2 sprayed with the processing solution by the upper and lower spray nozzles 5 and 3 in one processing station is located before the can 2 moves to the next processing station. An air injection nozzle 8 for blowing off the processing liquid remaining in the concave portion of the can bottom 2b, a processing liquid flowing down the inner and outer surfaces of the can body and accumulating at the open end of the can 2, and a staying processing liquid on the belt And a suction nozzle 9 for sucking the water are provided to face up and down with the belt conveyor 10a on the transport side interposed therebetween.

Pressurized air is supplied to the air injection nozzle 8 from a compressor (not shown).

On the other hand, referring to FIG. 4, the suction nozzle 9 has a plurality of slits 90 on its upper surface which are orthogonal to the traveling direction of the conveyor belt 10a and have a length substantially equal to the width of the belt conveyor 10. The processing liquid is connected to an air blower 92 via a processing liquid recovery tank 91 below and outside the processing liquid tank (the degreasing liquid tank 1A3 in this figure), and the processing liquid is sucked by the air blower. Note that the slit 90 may be a single slit as long as a sufficient suction action is performed.

The processing liquid recovery tank 91 is provided with a filter 93 that allows gas to pass therethrough but not liquid at a position slightly below the connection part to the exhaust fan 92. The liquid is stored in the processing liquid recovery tank 91.

Further, in order to reuse the processing liquid collected in the processing liquid recovery tank 91, the processing liquid storing the same processing liquid from the lower side wall of the processing liquid recovery tank 91 via a pump 94. The processing liquid recovery pipe 95 is piped through the upper side wall of the storage tank and opens into the tank 143.
Is provided.

The pump 94 is activated by an instruction from the controller C which receives an ON signal from a tank level switch 96 provided outside the side wall of the processing liquid recovery tank 91, and is stored in the tank 91. The processing liquid is returned to the processing liquid storage tank, and the operation is stopped in response to a command from the controller C that has received the OFF signal of the switch 96.

It is sufficient that the belt conveyor used in the present invention has a structure through which the processing liquid and the pressurized air can pass. In this example, a belt conveyor newly developed by the present inventors was used. That is, that shown in FIG.

A number of stainless steel unit members 12 formed by bending in a U-shape are prepared, and the bottom 12b of one member 12 is fitted into the open end 12c of the next member. Prepare an appropriate number of 11
A long stainless steel connecting rod 13, 13, 13,... Is penetrated and inserted into each fitting portion of the unit member of each chain at a rotatable, parallel, and equal interval to form a chain group. The rods 13 are connected to the unit members 12 as shown in the figure.
Is mounted so as to be located substantially below the top surface 12a of the plate and substantially at the center of the plate width. Reference numeral 14 denotes a stainless steel intermediate rod disposed at the same height as the connecting rods 13 and between the rods so as to be parallel and rotatable. In this example, the intermediate rods are mounted one by one between the connecting rods. This intermediate rod is made slightly longer than the diameter of the can body so that a can transport portion 10b having a width W enough to place the cans to be processed in a line is secured between the adjacent chains 11 and 11. , Between the opposing unit members of the adjacent chain. Thus, the chains 11, 11,...
The belt conveyor 10 consisting of b ... was formed, and it was constituted endlessly. The reason why the width W is made slightly longer than the can diameter is that the adjacent chains 11
This is to prevent the can from touching.

The connecting rod 13 is connected to the top surface 12a of the unit member.
Although placed below, the intermediate rod 14 is also set at the same height and has the same diameter as the connecting rod, so that the pass line P. L. (The mounting surface of the can) can be on the same line.

With such a configuration, the belt conveyor 10 has a large number of holes or open portions 1 through which the processing liquid sprayed from the upper and lower spray nozzles 4 and 6 can pass.
03. In FIG. 1, reference numeral 15 denotes a drive shaft of the belt conveyor 10, and teeth of a plurality of sprockets 16 attached thereto mesh with the chain.

Next, an embodiment of the surface treatment by the above-described apparatus will be described. First, each can transport section 10b of the belt conveyor 10
The cans 2 are inverted and distributed, and further, for each row of cans, the cans are arranged slightly apart from each other (indicated by d in FIG. 1).
And transport.

Next, at the degreasing station 1A1,
Spray the degreasing solution from above and below. This is the same process as in the prior art.

The can to be processed has a can diameter of 66 mm and a can volume of 350 m.
1 aluminum can, the conveying speed is 15.8 m / min, the injection amount of the degreasing solution is 6800 cm ³ / min, the spray pressure from the upper spray nozzle 5 is 5 kg / cm ² , and that from the lower spray nozzle 3 is 4 kg / cm ² (to prevent floating of the can). It is 4 kg / cm ² from the side spray nozzles 7 and 7 ′.

The can 2 sprayed with the degreasing liquid on the entire inner and outer surfaces as described above is then dripped with the degreasing liquid, and the air jet nozzle 8 and the suction nozzle 9 are disposed near the outlet of the station 1A1. To the place.

The spray pressure is 50 m from the air injection nozzle 8.
Air is injected with mAq (1 kg / cm ² is equal to 10000 mmAq) to blow off the degreasing solution remaining in the can bottom 2b and to remove the processing solution adhering to the outer surface of the side wall 2c with pressurized air. Forced away. on the other hand,
80 m suction force from slit 90 of lower suction nozzle 9
The processing liquid accumulated in the can opening 2a by mAq was sucked together with the processing liquid attached to the unit member 12 and the rods 13 and 14 of the conveyor belt 10 and hanging down. The suction force of the suction nozzle 9 causes
The flow speed of the processing solution attached to the outer surface was increased, and the processing time was saved.

The can thus degreased in this manner was then transported sequentially from the first washing station 1A2 to the last deionized water treatment station 1C2, and treated at each station in the same manner as described above.

As described above, when the air injection nozzle 8 and the suction nozzle 9 are arranged to face each other with the belt conveyor 10 on the conveyance side interposed therebetween, even if the injection pressure of air from the air injection nozzle 8 is increased, the suction nozzle 9 Even if the suction force is increased, the air does not flow turbulently because it flows almost directly below, and there is no danger that the inverted can is turned over. Therefore, the processing liquid accumulated in the can bottom 2b is strongly blown off, Conveyor side belt conveyor 1
The treatment liquid adhering to Oa could be sufficiently absorbed.

As a comparison, when the suction nozzle 9 is omitted, when the pressure of the air blown from the air injection nozzle 8 toward the bottom of the can body is increased to accelerate the forced flow of the processing liquid,
When measuring how far the air pressure can be increased without generating a falling can, up to 30m under the following conditions
It was known to be mAq. Experimental station Rinse station Can height 66 mm Can capacity 350 ml Can diameter 66 mm Can transport speed 15.8 m / min. That is, if air is blown at a pressure higher than this, the falling cans occur one after another, making it unusable for practical use. However, the suction nozzle 9
When this is installed, 80m exceeding this value 30mmAq
Even when spraying with mAq, there was no occurrence of falling over cans, confirming that the effect of the present invention was great.

Further, it was measured how much the amount of the processing liquid recovered from the can differs between when only the air injection nozzle 8 is used and when the suction nozzle 9 is used together.
It was as follows. This also shows that the effect of using the suction nozzle together is remarkable.

The experimental conditions are as follows. Processing speed 2,000 cans / min Spray pressure from air injection nozzle 50 mmAq Suction nozzle suction force 80 mmAq

Table 1 shows the experimental results.

[0057]

[Table 1]

First, the weight of the can after spraying air or the can after spraying air and suctioning with a suction nozzle was measured. After drying, the weight was calculated again by measuring the weight.

From the above results, when the can is moved to the next processing station 5 seconds after the spraying of the processing liquid, when the air injection nozzle and the suction nozzle are used together, the case where only the air injection nozzle is used Compared to 408
A liter / hour treatment liquid recovery will be achieved (only with can adhesions). Actually, in addition to this, the processing liquid adhering to the belt conveyor can also be recovered, so that the effect is extremely large.

In addition to installing the suction nozzle at a position facing the air injection nozzle 8 and further adding the suction nozzle to the front position in the traveling direction of the belt conveyer, the recovery of the processing liquid can be further improved when the suction nozzle is installed next to it. From the experimental results.

Experimental conditions The same as the above experimental conditions except that the suction force of the additional suction nozzle was set to 50 mmAq.

Table 2 shows the experimental results.

[0063]

[Table 2]

However, it is necessary that the suction force of the suction nozzle provided in front is weaker than that of the nozzle provided opposite the air jet nozzle 8.

Further, as another comparison, it was measured how much the processing time was shortened by the difference in the flow rate of the processing liquid between the case where only the air injection nozzle 8 was used and the case where the suction nozzle 9 was used together. Table 3 shows the results.

[0066]

[Table 3]

The distance between the suction nozzle 9 and the can opening 2a is desirably 5 mm or less in order to maintain a strong suction force. If the suction nozzle is located far away from the opening end of the can, wind is generated (turbulent flow), and the can easily falls. According to the experimental results in which the spraying force, suction force, and other conditions were the same, no cans were seen to fall when the length was 5 mm or less, but at 7 mm, about 20% of the cans fell, and at 9 mm, they further increased. Most cans have fallen.

In the above description, D is used as the bottomed can body.
The present invention is applicable to a bottomed can body that performs surface treatment using a plurality of processing liquids, such as an impact can (a bottomed can body often used for aerosol cans). It is.

[0069]

As described above in detail, according to the present invention, in each processing liquid application stage or station, a predetermined bottomed can body is placed on a belt conveyor and passed over by being inverted. After spraying the processing liquid from above and below, before moving to the next station, pressurized air is injected from the air injection nozzle provided above to blow off the remaining processing liquid, Of the processing liquid adhering to the opening of the can or the belt conveyor is suctioned by the suction nozzle arranged below, so that the recovery rate of the processing liquid is increased and the processing liquid is taken to the next station. The processing solution contamination and dilution speed at the next station due to the reduction in the amount of the processing stream are suppressed.

Further, by the cooperative work of the air injection nozzle and the suction nozzle, air can be blown at a higher injection pressure while avoiding falling of the can, so that the recovery amount of the processing liquid and the time required for the recovery can be greatly reduced. To be improved.

[Brief description of the drawings]

FIG. 1 is a schematic plan view of a surface treatment apparatus used in an embodiment of the present invention.

FIG. 2 is a sectional side view taken along the line II-II in FIG.

FIG. 3 is a sectional front view taken along the line III-III of FIG. 2;

FIG. 4 is an explanatory view showing a main part of a suction nozzle.

5A is a plan view showing a part of the belt conveyor used in the embodiment of the present invention, and FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Surface treatment tank 1A Pre-wash zone 1B Chemical conversion zone 1C Post-wash zone 2 DI can 4 Lower spray nozzle 6 Upper spray nozzle 8 Air jet nozzle 9 Suction nozzle 10 Belt conveyor 11 Endless chain

Continuation of the front page (56) References JP-A-50-77440 (JP, A) JP-A-47-33348 (JP, A) JP-A-5-68957 (JP, A) JP-A-56-84291 (JP) U.S. Pat. No. 5,642,792 (JP, U) U.S. Pat. No. 4,582,287 (JP, U) U.S. Pat. (Int.Cl. ⁷ , DB name) B08B 9/34

Claims (8)

(57) [Claims] 1. A bottomed can body is placed upside down on an endless belt conveyor through which gas and liquid can pass through a surface treatment tank including a plurality of treatment liquid application sections, and is conveyed in a horizontal direction. In the step, a method of spraying a predetermined processing liquid from above to the can body to perform an inner / outer surface treatment of the can body,
In at least one treatment liquid application step, pressurized air is injected from above to the bottom of the can body after the treatment liquid has been sprayed, and stored and adhered to the open end of the can body. A method for treating the inner and outer surfaces of a bottomed can body, comprising a step of sucking a treatment liquid from below. 2. The inner / outer surface of a bottomed can body according to claim 1, wherein the step of applying the treatment liquid comprises the steps of degreasing, primary rinsing, chemical conversion, secondary rinsing and deionized water treatment. Processing method. 3. A gas / liquid passage comprising a surface treatment tank having a plurality of treatment liquid application sections, and a transport section for horizontally transferring the inverted bottom-mounted can body in the surface treatment tank. A possible endless belt conveyor, and each processing liquid application section is provided above and below a conveying section of the belt conveyor with a group of upper and lower spray nozzles for spraying the same processing liquid. A processing liquid storage tank disposed below the lower spray nozzle; and a means for supplying the processing liquid in the processing liquid storage tank to the lower and upper spray nozzles. In the outer surface treatment device, in at least one treatment liquid application section, the upper and lower spray nozzles are arranged in front of the belt conveyor in the traveling direction, and
An inner / outer surface treatment for a can body with a bottom, characterized in that an air injection nozzle is disposed downward above the belt conveyor, and a suction chisel is disposed below the belt conveyor. apparatus. 4. The surface treatment tank has a degreasing station, a first rinsing station, a chemical conversion station, a second rinsing station, and a deionized water treatment station as a plurality of treatment liquid application sections. Inner / outer surface treatment equipment for bottomed can bodies. 5. The inner / outer surface treatment apparatus for a can body with a bottom according to claim 3, wherein the air injection nozzle and the suction nozzle are disposed at positions facing each other with the belt conveyor interposed therebetween. 6. The suction nozzle is disposed at a position facing the air jet nozzle across the belt conveyor, and at a position further forward than the position in the traveling direction of the belt conveyor. Inner / outer surface treatment equipment for bottomed can bodies. 7. The inner / outer surface treatment apparatus for a can body with a bottom according to claim 3, wherein the distance between the suction nozzle and the opening end of the can body to be treated is 5 mm or less. 8. The processing liquid collecting tank according to claim 3, further comprising a processing liquid collecting tank communicating with the suction nozzle, a pump and a piping system for returning the processing liquid in the processing liquid collecting tank to the processing liquid storing tank. The inner / outer surface treatment apparatus for a can body with a bottom according to the above item.