JP2007301539A - Liquid injection apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid injection apparatus capable of improving workability while suppressing cost rise. <P>SOLUTION: The liquid injection apparatus is provided with a high-temperature water tank 11 in which a liquid such as high-temperature washing water or the like is stored, a solvent tank 16 in which a solvent (film-forming agent for coating) or the like is stored, a 1st flow passage for supplying the washing water or the like from the high-temperature water tank 11 to a liquid injection valve nozzle 13 via pressure elevation to a predetermined pressure level with the use of a liquid squeeze pump 12, and a 2nd flow passage that is connected to the 1st flow passage for supplying the solvent or the like from the solvent tank 16 to the 1st flow passage, wherein the flow rate of the 1st flow passage is determined to be variable so as to control the negative pressure at the connection part between the 1st and the 2nd flow passages and thus to control the flow of the solvent or the like to the liquid injection valve nozzle 13, so that the type of injection liquid can be changed with the simple configuration. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a liquid ejecting apparatus that ejects a plurality of liquids by switching with a simple configuration using a single fuel ejecting apparatus.

  As pre-painting work, metal surfaces such as iron-based, zinc-based, or aluminum-based surfaces should be coated with a chemical solution such as phosphate prior to coating in order to improve corrosion resistance and coating adhesion. Chemical treatment is applied. Further, a cleaning operation is performed simultaneously by spraying cleaning water maintained at a high pressure on the metal surface after the chemical treatment to remove the chemical solvent floating on the surface without adhering to the metal surface. Such pre-processing work is usually performed by the following steps.

1. Spray the phosphate solution onto the painted plate.
2. Washing water (preferably high-temperature water) pumped by a high-pressure pump is blown onto the metal surface that is a paint plate.

  Here, in the conventional method, the operation of spraying the cleaning water and the chemical solution with completely different liquid jet machines is performed. Further, according to the aspect of the liquid ejecting apparatus described in Japanese Patent Application Laid-Open No. 2005-81301, the tank containing the cleaning water and the tank containing the chemical solution are pressurized to one same ejecting nozzle through a different system passage. Depending on the purpose of use, it is also considered to operate the switching valve in front of the injection nozzle to inject either cleaning water or a chemical solution from the injection nozzle.

JP 200581301 A

  However, when a completely different liquid jet machine is used, the cost and workability are significantly deteriorated. In addition, in the case of performing cleaning and chemical treatment by switching the passage of cleaning water and chemical solution, a separate pump for pumping liquid to each path is required, which is disadvantageous in terms of cost, There has been a problem that the apparatus is also enlarged.

  Accordingly, the present invention has been made to solve the above-described problems, and an object thereof is to provide a liquid ejecting apparatus capable of suppressing an increase in cost and improving workability. In particular, the present invention relates to a liquid ejecting apparatus that ejects cleaning water and a chemical solution onto a coating member as a pretreatment operation for a painting operation.

Means for solving the problem

  According to a first aspect of the present invention, there is provided a liquid ejecting apparatus including a first tank in which a first liquid is stored, a second tank in which a second liquid is stored, and a first liquid from the first tank by a liquid pump. A first feed passage that increases pressure to flow to the injection valve and a second feed that is connected to the first feed passage and feeds the second liquid from the second tank to the first feed passage. A liquid injection device including a flow path, wherein the flow rate of the first liquid flow path is variable to control flow of the second liquid fuel to the first flow path. The liquid ejecting apparatus is characterized.

    According to the first aspect of the invention, by increasing the flow velocity of the first flow passage, the negative pressure at the opening where the first flow passage and the second flow passage communicate is increased, and the negative pressure is reduced. By changing, the flow rate of the second liquid to the injection port can be changed. Therefore, when ejecting at least two kinds of liquids, it is not necessary to use completely different liquid ejecting apparatuses or to switch the kind of liquid to be ejected by using a switching valve, thereby reducing cost and workability. Dramatically improved. Here, when the 1st liquid is used as tap water, it attaches that the 1st tank serves as a tap of tap water.

  A liquid ejecting apparatus according to a second invention is characterized in that, in the configuration of the first invention, the flow velocity of the first flow passage is made variable by making the liquid ejection area of the injection valve variable. The liquid ejecting apparatus according to claim 1.

  The smaller the liquid ejection area, the greater the flow resistance of the first flow passage, and the lower the flow velocity of the liquid flowing through the connecting portion between the first flow passage and the second flow passage. On the contrary, the larger the liquid ejection area, the smaller the flow resistance of the first flow passage, and the higher the flow velocity of the liquid flowing through the connecting portion between the first flow passage and the second flow passage. Therefore, according to the second aspect, by making the liquid ejection area variable, for example, the flow velocity of the first flow passage can be easily changed at a low cost compared to the case where the capacity of the liquid pump is made variable. It can be.

  According to a third aspect of the present invention, there is provided the liquid ejecting apparatus according to the first and second aspects of the invention, wherein the ejection valve has a housing having two parts, a small inner diameter portion and a large inner diameter portion, and slides in the housing. The piston portion connected to the first flow passage, and having an opening at the tip of the piston portion, the outer diameter of the housing being substantially the same as the inner diameter of the small inner diameter portion of the housing. A through hole that penetrates the internal passage of the piston portion is provided on the outer peripheral surface of the piston portion that faces the wall surface of the housing, and the position of the through hole is made small by sliding the housing or the piston portion. The liquid ejecting apparatus according to claim 1, wherein the liquid ejecting apparatus is movable to an inner diameter portion or a large inner diameter portion.

  According to the third aspect, the liquid ejection area of the liquid pressure-fed from the first flow passage can be made variable by the operation of sliding the housing provided in the injection valve. Usually, the operator works with the injection valve housing in hand, and therefore, when switching the flow rate of the first flow passage, it is possible to omit troublesome operations such as temporarily interrupting the operation and switching a separate switching valve. And workability is dramatically improved.

  4. The liquid ejecting apparatus according to claim 1, wherein the first liquid is cleaning water, and the second liquid is a coating film forming agent. 5. is there.

  According to the fourth invention, cleaning and film formation can be performed by the same liquid ejecting apparatus as a pretreatment for coating. Since the coating liquid chemical agent for coating of the second liquid and the cleaning water as the first liquid are mixed and injected from the injection valve, it is not necessary to previously dilute the coating film chemical agent for coating with the solution, or the amount of the solution for thinning Therefore, the capacity of the second tank can be reduced, and the enlargement of the apparatus can be avoided.

The invention's effect

  According to the above invention, at least two types of liquid ejection modes can be switched with a simple configuration in which the flow velocity of the liquid passage is changed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a schematic configuration of a liquid ejecting apparatus according to an embodiment of the present invention.

  The high-temperature water tank 11 storing the high-temperature water is connected to the liquid pumping pump 12 via the first liquid passage 14, and the high-temperature water stored in the high-temperature water tank 11 by the liquid pumping pump 12 is supplied to the second liquid passage 15 ( (Corresponding to the first flow passage described in the claims), the liquid is jetted to the liquid jet nozzle 13. Here, the high-temperature water stored in the high-temperature water tank 11 is preferably kept at 45 to 60 degrees, and the liquid pump 12 supplies high-pressure liquid to the liquid jet nozzle 13 at a maximum of 8.5 MPa.

  The solvent tank 16 storing the chemical solvent is connected to the second liquid passage 15 via the third liquid passage 17 (corresponding to the second flow passage described in the claims), and is connected to the liquid injection nozzle 13 with the chemical solution. Can be supplied. The chemical solution is a chemical solvent for forming a phosphate film on a steel, zinc, or aluminum coated plate. Specifically, the chemical solution contains NaHPO4 · 2H2O at a component concentration of 70 to 85%, a pH adjusting agent, an oxidizing agent, NaF. And a chemical solvent containing a surfactant.

  The third liquid passage 17 and the second liquid passage 15 are connected and supported by a connecting member 21 disposed in the middle of the second liquid passage 15 as shown in FIG. Both ends of the connecting member 21 are communicated with the second liquid passage 15, and a communication hole 22 communicating with the third liquid passage 17 communicating with the solvent tank 16 is provided at the central portion of the connecting member 21. The third liquid passage 17 and the communication hole 22 are connected by a nipple 25 via a spring 23 and an O-ring 24.

  The inner passage of the connecting member 21 has a venturi structure, and the inner passage central portion diameter is smaller than the inner diameter of the second liquid passage 15 connected to both ends, and the inner passage of the connecting member 21 facing the communication hole 22 is formed. The flow velocity in the passage is increased.

  Next, the structure of the liquid injection nozzle 13 will be described in detail with reference to FIG. In the liquid jet nozzle 13 of this embodiment, the piston 33 is slidably fitted into the housing hole 32 formed in the base surface of the housing 31, and the conical tip 34 of the piston 33 abuts on the tip of the housing hole 32. A conical valve seat portion 35 is provided, and a slit-like nozzle 36 that opens from the valve seat portion 35 to the distal end surface of the housing 31 is provided. A needle valve 37 extending to the slit-like nozzle 36 is further provided at the conical tip of the piston 33, and the liquid supplied from the second liquid passage 15 is ejected.

  Four small holes 38 that penetrate the inner passage of the piston 33 are provided in the downstream body of the tip portion 34 of the piston 33, and a seal ring 39 is disposed between the small hole 38 and the tip portion 34. The housing 31 is slidably attached to the piston 33, and the movement in the A direction is allowed until the stopper 40 provided on the housing 31 comes into contact with the convex portion 41 attached to the body of the piston 33. ing.

  The housing 31 is divided into two parts having different inner diameters, and the inner diameter of the first part 31A close to the slit-like nozzle 36 is substantially the same as or slightly larger than the outer diameter of the piston 33. Further, the inner diameter of the second part 31B far from the slit-like nozzle 36 is formed to be about 10% larger than the outer diameter of the piston 33, and there is a predetermined space between the piston 33 and the second part 31B. It has a configuration.

  Next, the injection switching function between the high-temperature water and the chemical solution in this embodiment will be described. As the flow velocity through the communication member 21 increases, the negative pressure generated in the communication hole 22 increases, and the chemical solvent stored in the solvent tank 16 passes through the communication hole 22 through the third liquid passage 17 to form the second liquid. It is supplied to the passage 15. Then, the supplied chemical solvent is mixed with high-temperature water pumped from the liquid pumping pump 12 and sprayed as a chemical solution from the liquid spray nozzle 13, thereby forming a coating on the coated plate.

  On the other hand, if the flow velocity through the communication member 21 is slow, the negative pressure generated in the communication hole 22 is reduced, the chemical solvent from the solvent tank 16 is not supplied to the second liquid passage 15, and high temperature water is supplied from the liquid injection nozzle 13. Only the spray is sprayed and the painted plate can be cleaned.

  As shown in FIG. 3, when the conical tip 34 of the piston 33 is in contact with the valve seat 35 of the housing 31, the small hole 38 provided in the housing 31 is positioned in the first part 11 </ b> A of the housing hole 32. The small hole 38 is closed by the wall surface of the first part 11A. In this state, the liquid supplied to the piston 33 through the second liquid passage 15 is injected only from the needle valve 37 of the piston 33.

  Here, the high-temperature water supplied from the liquid pumping pump 12 at a high pressure passes through the second liquid passage 15 and is jetted through the needle valve 37 having a small jet nozzle area. Accordingly, the spray speed of the spray liquid is increased, and the spraying liquid is sprayed onto the paint plate, whereby the paint plate can be effectively cleaned. Further, since the area of the injection port is small, the flow resistance of the second liquid passage 15 is increased, and the flow velocity through the communication member 21 that is a communication portion between the second liquid passage 15 and the third liquid passage 17 is reduced. Therefore, the negative pressure at the connecting portion between the second liquid passage 15 and the third liquid passage 17 is reduced, and no chemical solvent is supplied from the third liquid passage 17 to the second liquid passage 15, and only high-temperature water is second. The liquid is supplied from the liquid passage 15 to the liquid jet nozzle 13.

  Next, as shown in FIG. 4, in a state where the housing 31 is moved in the direction A and the stopper 40 is in contact with the convex portion 41 attached to the body of the piston 33, the small hole 38 provided in the piston 33 has the first hole 38. Open to 2 part 31B. Then, the liquid supplied from the second liquid passage 15 is ejected from the needle valve 37 and the small hole 38. Here, a space portion 42B is formed between the small hole 38 and the housing wall surface of the second part 31B, and the liquid ejected from the small hole 38 once accumulates in the space portion 42B, and the first part 31A of the housing 31 Together with the liquid supplied to the space portion 42A and finally ejected from the needle valve 37, it is ejected from the slit-shaped nozzle 36. Further, a seal ring (not shown) is inserted into the liquid so that the liquid ejected from the small hole 38 does not leak from the connecting portion between the housing 31 and the second liquid passage 15.

  Since the liquid supplied from the second liquid passage 15 to the piston 33 is ejected from the needle valve 37 and the small hole 38, the flow resistance is higher than that ejected from only the needle valve 37 as shown in FIG. Get smaller. Therefore, the flow velocity of the communication portion between the second liquid passage 15 and the third liquid passage 17 is increased, and the negative pressure generated in the communication hole 22 is increased, so that the chemical solvent passes from the solvent tank 16 through the third liquid passage 17. A chemical solution supplied to the second liquid passage 15 and mixed with high-temperature water is ejected from the liquid ejection nozzle 13.

  As described above, the chemical solvent can be mixed into the high-temperature water by changing the flow velocity of the passage through which the high-temperature water flows. Therefore, the injection of only the high-temperature water and the chemical solvent and the high-temperature water can be performed with a very simple configuration. The injection of the mixed chemical solution can be switched. Further, according to a preferred embodiment, it is possible to switch between injection of only high-temperature water and injection of a chemical solution only by sliding the housing 31. Usually, the operator performs the operation by holding the housing 31 of the liquid injection nozzle 13 in his / her hand, so that the troublesomeness of temporarily interrupting the operation with the switching is eliminated, and the operation efficiency is greatly improved. In particular, in the case where a switching valve is separately provided to switch injection of high-temperature water and mixed solution, it is necessary to once remove the operator's hand from the injection nozzle, so that the work efficiency is much higher than that of such a configuration. Improvement can be achieved.

  The embodiments disclosed herein are illustrative and non-restrictive in every respect. If a slight increase in cost is acceptable, a variable capacity liquid pump can be used to change the flow rate of the first flow passage. The scope of the present invention is shown not by the above description but by the scope of claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

1 is a schematic configuration diagram of a liquid ejecting apparatus according to an embodiment of the invention. FIG. 6 is a structural diagram of a connecting member disposed in the middle of the second liquid passage and the third liquid passage according to the embodiment of the present invention. Sectional drawing of the liquid injection valve nozzle which concerns on embodiment of this invention (the 1) Sectional drawing of the liquid injection valve nozzle which concerns on embodiment of this invention (the 2)

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 High temperature water tank 12 Liquid pressure pump 13 Liquid injection nozzle 14 1st liquid passage 15 2nd liquid passage 16 Solvent tank 17 3rd liquid passage 21 Connection member 22 Connection hole 23 Spring 24 O-ring 31 Housing 31A 1st part 31B 2nd Part 32 Housing hole 33 Piston 34 Tip portion 35 Valve seat portion 36 Slit-shaped nozzle 37 Needle valve 38 Small hole 39 Seal ring 40 Stopper 41 Protruding portion 42A Space portion 42B Space portion

Claims (4)

A first tank in which the first liquid is stored, a second tank in which the second liquid is stored, and a first liquid from the first tank that is pressurized to a predetermined pressure by a liquid pump and is sent to an injection valve. A liquid ejecting apparatus comprising: a first flow path; and a second flow path connected to the first flow path and configured to flow the second liquid from the second tank to the first flow path. There,
A liquid ejecting apparatus that controls flow of the second liquid fuel to the first flow passage by changing a flow rate of the first flow passage.   2. The liquid ejecting apparatus according to claim 1, wherein the flow velocity of the first flow passage is variable by making the liquid ejection area of the ejection valve variable. 3.   The injection valve has a housing having two parts, a small inner diameter portion and a large inner diameter portion, and is slidably disposed in the housing, and has an outer diameter substantially the same as the inner diameter of the small inner diameter portion of the housing. A piston portion connected to the first flow passage, the front end of the piston portion being open, and a penetrating through the internal passage of the piston portion on the outer peripheral surface of the piston portion facing the wall surface of the housing 3. The position of the through hole can be moved to a small inner diameter portion or a large inner diameter portion of the housing by providing a hole and sliding the housing or the piston portion. Liquid ejector.     4. The liquid ejecting apparatus according to claim 1, wherein the first liquid is cleaning water, and the second liquid is a coating film forming agent.

Images