JP2004154641A - Multi-liquid mixing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the back flow of a mixed liquid inside a mixer to the side of a feeding passage at the time when the discharging operation of the mixed liquid is stopped. <P>SOLUTION: The midway part of a mixed liquid hose 28 connected to a static mixer 26 is provided with a flowmeter 35, and the performance and stop of the discharging operation in a spray gun 29 are detected based on the measured result by the flowmeter 35. When a controller judges that the discharging operation of the spray gun 29 is stopped based on a signal from the flowmeter 35, it operates a solenoid valve 17, closes an opening and closing valve under feeding a liquid to a premixer 19, and stops the feeding operation of the liquid. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a multi-liquid mixing apparatus that mixes a plurality of liquids at a fixed ratio, and more particularly to a multi-liquid mixing apparatus suitable for a coating machine that discharges and paints while mixing a main agent and a curing agent.
[0002]
[Prior art]
For example, in a two-component coating machine that discharges while mixing the main agent and curing agent at a predetermined ratio, after supplying the main agent and curing agent alternately to the premixer via separate paths, both solutions are supplied to the static mixer. A mixing device for mixing is provided. A spray gun is connected to the static mixer via a hose, and a mixed liquid (paint) is discharged from the spray gun (for example, see Patent Document 1).
[0003]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 11-347460 (second page, FIG. 1)
[0004]
[Problems to be solved by the invention]
In the above-described conventional mixing apparatus, when the main agent and the curing agent are alternately supplied to the premixer, they are pushed out and the mixed solution in the premixer flows into the static mixer, and further, the mixed solution in the static mixer moves toward the spray gun. Extruded and discharged. That is, a balance is maintained between the operation of discharging the mixed liquid from the spray gun and the operation of supplying the main agent and the curing agent to the premixer.
[0005]
Therefore, if the balance is lost due to the stop of the discharge operation of the spray gun, the mixed liquid in the premixer may flow backward to the main agent or curing agent supply source side. Therefore, a backflow prevention valve is provided in the supply path from the supply source of each liquid.
[0006]
However, when the backflow prevention valve stops functioning for some reason, the backflow of the liquid mixture from the premixer cannot be prevented, and there is a problem that the backflowed liquid mixture flows toward the supply source through the supply path.
[0007]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a multi-liquid mixing apparatus that can prevent the mixed liquid in the mixer from flowing backward to the supply path when the mixed liquid discharge operation is stopped. is there.
[0008]
[Means for Solving the Problems]
The multi-liquid mixing apparatus according to claim 1 of the present invention is configured to independently supply a plurality of different liquids to the mixer and a mixer that mixes the liquids by sequentially supplying a plurality of different liquids. A liquid supply operation for sequentially supplying the plurality of liquids to the mixer by controlling an opening / closing operation of the opening / closing valve And a spray gun connected to the mixer via a discharge path for discharging the liquid mixture in the mixer, wherein the liquid supply means executes and stops the liquid supply operation. It is characterized in that it is interlocked with the execution and stop of the discharge operation of the mixed liquid from the gun.
[0009]
According to the above configuration, the liquid supply means closes the open / close valve in the open state when the discharge operation of the spray gun is stopped, stops the liquid supply operation, and opens the open / close valve when the discharge operation is executed. Then, the liquid supply operation is resumed. That is, when the discharge operation of the mixed liquid from the spray gun is stopped, all the on-off valves provided in the supply path are closed, and the liquid flow in the supply path and the discharge path is stopped. Therefore, the mixed liquid in the mixer does not flow backward to the supply path side.
[0010]
In this case, the discharge path is provided with discharge detection means for detecting the execution and stop of the discharge operation of the mixed liquid from the spray gun, and the liquid supply operation by the liquid supply means is executed based on the detection result of the discharge detection means. It is good to comprise so that it may stop (invention of Claim 2).
[0011]
The discharge detection means outputs a signal corresponding to the execution and stop of the discharge operation of the spray gun. Therefore, the liquid supply means can execute or stop the liquid supply operation based on the signal from the discharge detection means. In this case, the discharge detection means can be composed of a flow meter for detecting the flow rate of the mixed liquid flowing through the discharge path, a pressure gauge for detecting the pressure in the discharge path, and the like.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an overall configuration diagram schematically showing a two-component mixing type coating machine 1 (corresponding to a multi-component mixing device) according to the present embodiment. The coating machine 1 according to the present embodiment includes three pressure feed pumps 2 to 4 constituting a main agent supply source, one pressure feed pump 5 constituting a curing agent supply source, and a pressure feed pump 6 for a cleaning thinner. . Although not shown, the pumps 2 to 6 are connected to tanks for storing a main agent, a curing agent, and a cleaning thinner, respectively.
[0013]
Further, all the pressure pumps 6 are connected to the manifold 7. The manifold 7 is internally divided into a main agent flow path 8 and a hardener flow path 9. On / off valves 10 to 13 are respectively provided at the four inlets of the main agent flow path 8, and the main pumping pumps 2 to 4 are connected to the on / off valves 10 to 12. In addition, on / off valves 14 and 15 are respectively provided at the two inlets of the curing agent passage 9, and the on-off valve 14 is connected to the pressure-feed pump 5 for the curing agent. A pressure pump 6 of the cleaning thinner is connected to the on-off valves 13 and 15.
[0014]
The on-off valves 10 to 15 are pneumatically driven for explosion-proof reasons. Pressurized air for driving the on-off valves 10 to 15 is supplied from a pressurized air supply source 16 via an electromagnetic valve 17.
[0015]
An outlet of the main agent flow path 8 of the manifold 7 is connected to a premixer 19 via a main agent passage 18 (corresponding to a supply path). The outlet of the hardener flow path 9 of the manifold 7 is connected to the premixer 19 via a hardener path 20 (corresponding to a supply path). In the middle of the main agent passage 18 and the hardener passage 20, flow meters 21 and 22 and backflow prevention valves 23 and 24 are provided, respectively.
[0016]
The premixer 19 has a double cylindrical structure having a distribution pipe inside the mixing chamber, similar to the premixer described in, for example, Japanese Patent Laid-Open No. 11-347460. The main agent passage 18 is connected to a mixing chamber, and the curing agent passage 20 is connected to a distribution pipe.
[0017]
When the main agent and the curing agent are alternately supplied to the mixing chamber and the distribution pipe of the premixer 19 so as to have a predetermined mixing ratio, both liquids are discharged from the mixing chamber outlet in a roughly mixed state. A static mixer 25 is connected to the mixing chamber outlet, and the main agent and the curing agent are mixed almost uniformly in the static mixer 25. The premixer 19 and the static mixer 25 constitute a mixer 26.
[0018]
A drain valve 27 is connected to the discharge port of the static mixer 25. A spray gun 29 is connected to one outlet of the drain valve 27 via a mixed liquid hose 28 (corresponding to a discharge path). A flow meter 35 is provided in the middle of the mixed solution hose 28. Further, a drain hose 30 is connected to another outlet portion of the drain valve 27, and a drainage tank 31 is disposed at the tip of the drain hose 30.
[0019]
The spray gun 29 has a discharge valve that is opened and closed by a manual operation by an operator. By opening the discharge valve, the mixed liquid in the static mixer 25 is discharged from the spray gun 29 through the mixed liquid hose 28, and by closing the discharge valve, the discharge operation of the mixed liquid from the spray gun 29 is stopped. To do.
[0020]
The drain valve 27 is a pneumatically driven type similar to the on-off valves 10 to 15. Pressurized air for driving the drain valve 27 is supplied via a solenoid valve from a pressurized air supply source (not shown). The liquid flowing into the drain valve 27 from the static mixer 25 flows to the mixed solution hose 28 side during the painting operation, and flows to the drain hose 30 side during the cleaning operation.
[0021]
FIG. 2 schematically shows the electrical configuration of the coating machine 1 according to the present embodiment. The control device 32 controls the control program for controlling various operations of the coating machine 1, the premixer 19 and the mixer 26. Various data such as capacity are stored in advance. The control device 32 is connected with flow meters 21, 22, 35 and operation keys 33. In addition, the electromagnetic valve 17 and the indicator 34 are connected to the control device 32.
[0022]
The flow meters 21, 22, and 35 are configured to generate one pulse signal by measuring a constant flow rate, for example. In particular, the flow meter 35 measures the flow rate of the mixed liquid flowing through the mixed liquid hose 28 as the mixed liquid is discharged from the spray gun 29. Therefore, in this embodiment, the flow meter 35 constitutes a discharge detection means.
[0023]
The operation keys 33 and the indicator 34 are provided on an operation panel (not shown) provided in the coating machine 1. The operation key 33 is used for setting the mixing ratio of the main agent and the curing agent, the color change of the paint (selection of the main agent), and the like, and the indicator 34 displays the operation status of the coating machine 1 and reports an abnormality. Is to do. The control device 32 controls the drive of the display 34 and the electromagnetic valve 17 in accordance with a control program stored in advance based on the pulse signals from the flow meters 21, 22, 35, the operation signals of the operation keys 33, and the like. It has become. In the present embodiment, the control device 32 and the electromagnetic valve 17 constitute liquid supply means.
[0024]
Next, the operation of the above configuration will be described. When the operation key 33 is operated to set the main agent type, the mixing ratio of the main agent and the curing agent, etc., the control device 32 determines the main agent and the main agent in one supply cycle based on the set mixing ratio and the capacity of the premixer 19. The amount of hardener supplied is calculated and stored.
[0025]
When the start of the liquid supply operation is instructed, the electromagnetic valve 17 is actuated based on a command signal from the control device 32, and any one of the on-off valves 10-12 and the on-off valve 14 are alternately opened at regular intervals. . Thereby, the liquid supply operation is executed. At this time, the control device 32 detects the supply amount of the main agent to the premixer 19 based on the pulse signal input from the flow meter 21, and supplies the curing agent to the premixer 19 based on the pulse signal input from the flow meter 22. Detect the amount. Based on these detection results, an operation command signal for the electromagnetic valve 17 is output at a predetermined timing.
[0026]
As a result, the main agent and the curing agent are sequentially supplied to the manifold 7 in a predetermined supply amount, respectively, and proceed to the premixer 19 through the main agent passage 18 and the curing agent passage 20. The main agent and the curing agent supplied to the premixer 19 are roughly mixed and then supplied to the static mixer 25 to be completely mixed.
[0027]
At this time, when the discharge valve of the spray gun 29 is opened by the operator, the liquid mixture in the static mixer 25 is discharged from the spray gun 29 through the liquid mixture hose 28. As a result, the flow meter 35 outputs a pulse signal corresponding to the flow rate of the mixed liquid flowing in the mixed liquid hose 28.
[0028]
In this state, when the discharge valve of the spray gun 29 is closed and the discharge operation is stopped, the mixed liquid does not flow in the mixed liquid hose 28, so the flow meter 35 does not output a pulse signal. Then, the control device 32 determines that the discharge operation has been stopped and outputs a supply stop signal to the electromagnetic valve 17. Thereby, the open on-off valve of the on-off valves for the main agent or the curing agent is closed, and the liquid supply operation to the premixer 19 is stopped. At this time, the control device 32 calculates and stores the remaining supply amount at the time when the on-off valve is closed from the input signal from the flow meter 21 or 22.
[0029]
When the discharge valve of the spray gun 29 is opened and the discharge operation is resumed, the flow meter 35 detects the flow of liquid in the mixed liquid hose 28 and generates a pulse signal. As a result, the control device 32 outputs an operation command signal to the electromagnetic valve 17. At this time, the control device 32 opens the on-off valve closed in response to the stop of the discharge operation for a time corresponding to the remaining amount of supply, and then again, any of the main agent on-off valves 10 to 12 at a predetermined timing. Then, the solenoid valve 17 is operated so as to alternately open the opening / closing valves 14 for the hardener and the curing agent.
[0030]
Thus, in this embodiment, the opening / closing of the on-off valve is controlled in accordance with the execution and stop of the discharge operation of the spray gun 29. Therefore, when the discharge operation from the spray gun 29 is stopped, the liquid supply operation to the premixer 19 is stopped, and the flow of all the liquids in the supply path and the discharge path is stopped. For this reason, the liquid mixture in the premixer 29 does not flow backward to the supply path.
[0031]
In the present embodiment, a flow meter 35 is provided in the middle of the mixed solution hose 28. When the flow meter 35 detects the flow of liquid in the mixed solution hose 28, the spray gun 29 performs a discharge operation. It was configured to be judged. Thereby, the operation of the spray gun based on the operator's operation can be indirectly detected.
[0032]
The present invention is not limited to the above-described embodiments, and for example, the following modifications and expansions are possible.
The discharge detection means can be constituted by a pressure sensor provided in the middle of the mixed solution hose in addition to the flow meter.
[0033]
An air flow sensor for detecting the flow of compressed air supplied to the spray gun in order to atomize the paint (mixed liquid) discharged from the spray gun is provided, and the spray gun discharge operation is performed based on the detection signal of the air flow sensor. You may make it detect execution and a stop. In this case, the air flow sensor constitutes the discharge detection means.
[0034]
You may comprise the discharge valve provided in a spray gun from a solenoid valve. Further, similarly to the on-off valves 10 to 15, the discharge valve may be constituted by a pneumatically driven valve, and pressurized air from a pressurized air supply source may be supplied via an electromagnetic valve. And it may comprise so that the operation signal of an electromagnetic valve may be inputted into control device 32, and it may be constituted so that execution and stop of discharge operation may be detected based on the input signal from the above-mentioned electromagnetic valve. In this case, the electromagnetic valve constitutes the discharge detection means.
[0035]
A flow meter is provided in the middle of the mixed solution hose to detect the flow of liquid in the mixed solution hose, and the discharge operation is detected based on the input signal from the solenoid valve. When the flow of the liquid in the mixed liquid hose is not detected, it may be configured to notify that clogging has occurred in the mixed liquid hose by sounding a buzzer or the like.
[0036]
When the flow meter 21 or 22 detects the flow of the liquid when the on-off valve is closed based on the discharge of the mixed liquid from the spray gun being stopped, the control device 32 sounds the buzzer. It may be configured to notify that an abnormality has occurred.
[0037]
The multi-component mixing apparatus of the present invention can also be applied to a mixing apparatus that mixes three liquids of a main agent, a curing agent, and a diluent, and an adhesive mixing apparatus that includes a plurality of types of liquids. Further, the present invention can be applied not only to paints and adhesives but also to all devices that mix various liquids. Furthermore, the present invention can be applied to an apparatus for mixing a gel-like liquid having a very high viscosity.
[0038]
【The invention's effect】
As is clear from the above description, the multi-liquid mixing device of the present invention links the execution and stop of the liquid supply operation to the mixer with the execution and stop of the discharge operation of the mixed liquid from the spray gun. It is possible to prevent the mixed liquid from flowing back to the supply path side as much as possible.
[Brief description of the drawings]
FIG. 1 is a diagram schematically showing an overall configuration of a two-component mixed coating machine according to an embodiment of the present invention. FIG. 2 is a block diagram showing an electrical configuration.
1 is a two-component mixing type coating machine (multi-component mixing device), 10 to 15 are on-off valves, 17 is an electromagnetic valve (liquid supply means), 18 is a main agent passage (supply passage), and 20 is a curing agent passage (supply passage). , 26 is a mixer, 28 is a mixed liquid hose (discharge path), 29 is a spray gun, 32 is a control device (control means, liquid supply means), and 35 is a flow meter (discharge detection means).

Claims (2)

A mixer for mixing the liquids by sequentially supplying a plurality of different liquids;
A plurality of supply passages for independently supplying a plurality of different liquids to the mixer;
An on-off valve provided in each of the supply paths;
A liquid supply means for performing a liquid supply operation for sequentially supplying the plurality of liquids to the mixer by controlling an open / close operation of the open / close valve;
In a multi-liquid mixing apparatus comprising a spray gun connected to the mixer via a discharge path for discharging the liquid mixture in the mixer,
The liquid supply device is configured to link the execution and stop of the liquid supply operation with the execution and stop of the discharge operation of the mixed liquid from the spray gun. Provided with a discharge detection means for detecting the execution and stop of the discharge operation of the mixed liquid from the spray gun provided in the discharge path;
2. The multi-liquid mixing apparatus according to claim 1, wherein the liquid supply means is configured to execute and stop the liquid supply operation based on a detection result of the discharge detection means.

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