JP2024064466A - Liquid injection device - Google Patents

Abstract

[Problem] To reduce the waste of liquid that occurs when the ejection of liquid from a head unit is stopped. [Solution] A liquid ejection device 1 comprising a liquid storage unit 8 for storing liquid 3, a head unit 2 having a nozzle 27 for ejecting the liquid 3 in a continuous flow 3a and converting the continuous flow 3a into droplets 3b to collide with an object in the form of droplets 3b, a liquid delivery unit 6 for delivering the liquid 3 from the liquid storage unit 8 to the head unit 2, a first flow path 7b having one end connected to the liquid delivery unit 6 and the other end connected to the head unit 2, a second flow path 7c having one end connected to the first flow path 7b, and a flow path switching unit 9 disposed at the connection between the first flow path 7b and the second flow path 7c, the flow path switching unit 9 opening the first flow path 7b and closing the second flow path 7c when ejecting the liquid 3 from the head unit 2, and closing the first flow path 7b and opening the second flow path 7c when ejecting the liquid 3 from the head unit 2. [Selected Figure] Figure 1

Description

The present invention relates to a liquid ejection device.

Conventionally, various liquid injection devices have been used to inject liquid onto a target object. Among such liquid injection devices, there are liquid injection devices that inject liquid at high pressure. For example, Patent Document 1 discloses an ultrasonic water jet device that injects water at high pressure from an ultrasonic nozzle.

JP 2007-523751 A

However, in a liquid injection device that injects liquid at high pressure as described in Patent Document 1, even after the injection of liquid from the head unit has stopped, liquid continues to leak from the nozzles of the head unit for a while, resulting in wasted liquid. This is because, for example, the tube that is the liquid flow path expands once when liquid is sent to the head unit at high pressure, and then contracts when the injection of liquid is stopped.

The liquid ejection device of the present invention for solving the above problem includes a liquid storage section for storing liquid, a head section having a nozzle for ejecting the liquid in a continuous flow and converting the continuous flow into droplets to impact the droplets on an object, a liquid delivery section for delivering the liquid from the liquid storage section to the head section, a first flow path through which the liquid flows, one end of which is connected to the liquid delivery section and the other end of which is connected to the head section, a second flow path through which the liquid flows, one end of which is connected to the first flow path, and a flow path switching section disposed at the connection between the first flow path and the second flow path, the flow path switching section being characterized in that when ejecting the liquid from the head section, the flow path switching section opens the first flow path and closes the second flow path, and when ejecting the liquid from the head section is stopped, the flow path switching section closes the first flow path and opens the second flow path.

1 is a schematic diagram illustrating a liquid ejecting apparatus according to a first embodiment. FIG. 11 is a schematic diagram illustrating a liquid ejecting apparatus according to a second embodiment. FIG. 11 is a schematic diagram illustrating a liquid ejecting apparatus according to a third embodiment. FIG. 11 is a schematic diagram illustrating a liquid ejecting apparatus according to a fourth embodiment.

First, the present invention will be briefly described.
In order to solve the above problem, a liquid ejection device of a first aspect of the present invention comprises a liquid storage section for storing liquid, a head section having a nozzle for ejecting the liquid in a continuous flow and converting the continuous flow into droplets so as to collide with a target object in the form of droplets, a liquid delivery section for delivering the liquid from the liquid storage section to the head section, a first flow path through which the liquid flows and having one end connected to the liquid delivery section and the other end connected to the head section, a second flow path through which the liquid flows and having one end connected to the first flow path, and a flow path switching section disposed at a connection between the first flow path and the second flow path, wherein the flow path switching section opens the first flow path and blocks the second flow path when ejecting the liquid from the head section, and blocks the first flow path and opens the second flow path when ejection of the liquid from the head section is stopped.

According to this aspect, the flow path switching unit opens the first flow path and closes the second flow path when liquid is ejected from the head unit, and closes the first flow path and opens the second flow path when liquid ejection from the head unit is stopped. Therefore, the flow of liquid toward the nozzle of the head unit is suppressed when liquid ejection from the head unit is stopped, so that the waste of liquid that occurs when liquid ejection from the head unit is stopped can be reduced.

The liquid injection device of the second aspect of the present invention is characterized in that in the first aspect, the other end of the second flow path is connected to the liquid storage section.

According to this aspect, the other end of the second flow path is connected to the liquid storage section. Therefore, the liquid collected from the other end of the second flow path can be easily reused.

The liquid ejection device of the third aspect of the present invention is characterized in that, in the first or second aspect, it is provided with a control unit that controls opening and closing of the first flow path and the second flow path of the flow path switching unit.

According to this aspect, a control unit is provided that controls the opening and closing of the first flow path and the second flow path of the flow path switching unit. This eliminates the need for the user to manually switch between the opening and closing of the first flow path and the second flow path of the flow path switching unit.

The liquid injection device of the fourth aspect of the present invention is characterized in that in the first aspect, the second flow path is located above the liquid level of the liquid stored in the liquid storage section in the direction of gravity.

According to this aspect, the second flow path is located above the liquid level of the liquid stored in the liquid storage section in the direction of gravity. Therefore, it is possible to prevent the liquid in the first flow path from flowing toward the head section due to the liquid flowing back from the liquid storage section toward the flow path switching section in the second flow path.

The liquid injection device of the fifth aspect of the present invention is characterized in that in the fourth aspect, the other end of the second flow path is connected to the liquid storage section, and the connection section between the second flow path and the liquid storage section is located above the liquid level of the liquid stored in the liquid storage section in the direction of gravity.

According to this aspect, the other end of the second flow path is connected to the liquid storage section, and the connection section between the second flow path and the liquid storage section is located above the liquid level of the liquid stored in the liquid storage section in the direction of gravity. Therefore, it is possible to particularly effectively prevent the liquid in the first flow path from flowing toward the head section due to the liquid flowing back from the liquid storage section toward the flow path switching section in the second flow path.

The sixth aspect of the liquid injection device of the present invention is characterized in that in the first or second aspect, the pressure in the second flow path is configured to be lower than atmospheric pressure when the injection of the liquid from the head portion is stopped.

According to this aspect, the pressure in the second flow path is configured to be lower than atmospheric pressure when the ejection of liquid from the head unit is stopped. Therefore, it is possible to prevent the liquid in the first flow path from flowing toward the head unit due to the liquid flowing back from the liquid storage unit toward the flow path switching unit in the second flow path.

The seventh aspect of the present invention is a liquid ejection device according to the first or second aspect, characterized in that it includes a storage section that stores the head section, and the storage section is located above the liquid level of the liquid stored in the liquid storage section in the direction of gravity.

According to this aspect, the device includes a storage section that stores the head section, and the storage section is located above the liquid level of the liquid stored in the liquid storage section in the direction of gravity. This makes it possible to prevent the liquid from leaking out of the head section stored in the storage section.

The eighth aspect of the liquid injection device of the present invention is characterized in that in the first or second aspect, the flow path switching unit is connected to the flow path through which the liquid flows at three or more ports.

According to this aspect, the flow path switching unit is connected to the flow path through which the liquid flows through three or more ports. With this configuration, the first flow path and the second flow path can be easily formed.

The ninth aspect of the liquid injection device of the present invention is the eighth aspect, in which the flow path switching unit is a three-way valve.

According to this embodiment, the flow path switching unit is a three-way valve. This configuration allows the flow path switching unit to have a simple configuration.

[Example 1]
Hereinafter, an embodiment of the present invention will be described with reference to the attached drawings. Here, the up-down direction in each drawing corresponds to the direction of gravity. First, an outline of a liquid injection device 1A according to Example 1, which is an example of a liquid injection device 1 of the present invention, will be described with reference to FIG. 1. The liquid injection device 1A of this example shown in FIG. 1 includes a liquid storage section 8 that stores the liquid 3 to be injected, a head section 2 having a nozzle 27, a flow path 7 that connects the head section 2 and the liquid storage section 8, a liquid delivery section 6 that has a pump or the like and delivers the liquid 3 from the liquid storage section 8 to the head section 2, and a control section 5 that has a control signal line 52 to the liquid delivery section 6.

Here, the head unit 2 has a nozzle 27 that sprays the liquid 3 in a continuous flow 3a and turns the continuous flow 3a into droplets 3b, which then collide with the target. Therefore, a user can use the liquid injection device 1A configured in this way to spray the liquid 3 from the nozzle 27 of the head unit 2 and collide the liquid 3 with a desired target, thereby applying the liquid 3 to the target, such as cleaning off any deposits that have adhered to the target. In other words, the liquid injection device 1A of this embodiment is a liquid injection device in which the continuous flow 3a of liquid 3 sprayed in a continuous state in direction b from one or more nozzles 27 provided in the head unit 2 is turned into droplets 3b, and the droplets 3b then collide with the target.

As described above, the liquid ejection device 1A of this embodiment is composed of a liquid storage section 8 that stores the liquid 3 as the ejection liquid, a liquid delivery section 6 that delivers the liquid 3, a control section 5 that controls the operation of the liquid delivery section 6, and a head section 2. In addition, by using a soft resin material or the like for the flow path 7 that connects the liquid storage section 8 to the head section 2, it is possible to improve the handling properties.

1, the liquid ejection device 1A of this embodiment includes, as flow paths 7, an upstream flow path 7a through which the liquid 3 flows and which connects the liquid storage section 8 to the liquid delivery section 6, a first flow path 7b through which the liquid 3 flows and which has one end connected to the liquid delivery section 6 and the other end connected to the head section 2, and a second flow path 7c through which the liquid 3 flows and which has one end connected to the first flow path 7b. The second flow path 7c serves as a circulation flow path that can return the liquid 3 that has flowed from the liquid storage section 8 via the upstream flow path 7a to the liquid storage section 8. A flow path switching section 9 is disposed at the connection between the first flow path 7b and the second flow path 7c.

The flow path switching unit 9 is configured to open the first flow path 7b and close the second flow path 7c when the liquid 3 is sprayed from the head unit 2, and to close the first flow path 7b and open the second flow path 7c when spraying of the liquid 3 from the head unit 2 is stopped. Note that the flow path switching unit 9A of this embodiment as the flow path switching unit 9 has a switching lever 11 that can rotate in a rotation direction R, and is configured so that the flow path 7 connected to the upstream flow path 7a can be switched between the first flow path 7b and the second flow path 7c by the user operating the switching lever 11.

In this way, the liquid injection device 1A of this embodiment is equipped with a flow path switching unit 9A that can open the first flow path 7b and close the second flow path 7c when ejecting the liquid 3 from the head unit 2, and close the first flow path 7b and open the second flow path 7c when ejecting the liquid 3 from the head unit 2 is stopped. Therefore, since the flow of the liquid 3 toward the nozzle 27 of the head unit 2 is suppressed when ejecting the liquid 3 from the head unit 2 is stopped, the liquid injection device 1A of this embodiment can reduce the waste of the liquid 3 that occurs when ejecting the liquid 3 from the head unit 2 is stopped.

As shown in FIG. 1, in the liquid injection device 1A of this embodiment, the other end of the second flow path 7c, which is opposite to the end connected to the flow path switching unit 9A, is connected to the liquid storage unit 8. Therefore, the liquid 3 recovered from the other end of the second flow path 7c can be easily reused. In this embodiment, the liquid 3 recovered from the other end of the second flow path 7c is recovered directly in the liquid storage unit 8, so it can be easily reused. However, this is not limited to such a configuration. For example, the liquid 3 may be recovered from the other end of the second flow path 7c in a container other than the liquid storage unit 8, and the user may put the recovered liquid 3 back into the liquid storage unit 8, thereby reusing the liquid 3.

1, in the liquid injection device 1A of this embodiment, the second flow path 7c is arranged to be located above the liquid level 3F of the liquid 3 stored in the liquid storage section 8 in the direction of gravity. Therefore, in the liquid injection device 1A of this embodiment, the liquid 3 in the first flow path 7a can be prevented from flowing toward the head section 2 due to the liquid 3 flowing back from the liquid storage section 8 toward the flow path switching section 9A in the second flow path 7c. Note that "the second flow path 7c is located above the liquid level 3F of the liquid 3 stored in the liquid storage section 8 in the direction of gravity" means that it is sufficient for most of the second flow path 7c to be located above the liquid level 3F in the direction of gravity, and it also means that a part of the second flow path 7c may be located below the liquid level 3F in the direction of gravity.

Also, from another perspective, as shown in FIG. 1, in the liquid injection device 1A of this embodiment, the other end of the second flow path 7c is connected to the liquid storage section 8 at a connection section 10, and the connection section 10 between the second flow path 7c and the liquid storage section 8 is located above the liquid level 3F of the liquid 3 stored in the liquid storage section 8 in the direction of gravity. Therefore, the liquid injection device 1A of this embodiment is particularly effective in preventing the liquid 3 in the first flow path 7a from flowing toward the head section 2 due to the liquid 3 flowing back from the liquid storage section 8 toward the flow path switching section 9A in the second flow path 7c.

From another perspective, as shown in FIG. 1, in the liquid injection device 1A of this embodiment, the pressure of the second flow path 7c when the injection of the liquid 3 from the head unit 2 is stopped is configured to be smaller than atmospheric pressure. This is because the liquid 3 in the second flow path 7c flows toward the liquid storage unit 8 due to its own weight. Therefore, the liquid injection device 1A of this embodiment can suppress the liquid 3 in the first flow path 7a from flowing toward the head unit 2 by the liquid 3 flowing back from the liquid storage unit 8 toward the flow path switching unit 9A in the second flow path 7c. Note that in this embodiment, the second flow path 7c is located above the liquid level 3F of the liquid 3 stored in the liquid storage unit 8 in the gravitational direction, so that the pressure of the second flow path 7c is smaller than atmospheric pressure, but this is not limited to such a configuration. For example, a pump or the like may be connected to the second flow path 7c or the liquid storage unit 8, and the second flow path 7c or the liquid storage unit 8 may be configured to have a negative pressure by driving the pump.

[Example 2]
A liquid injection device 1B of Example 2 will be described below with reference to FIG. 2. FIG. 2 is a diagram corresponding to FIG. 1 showing the liquid injection device 1A of Example 1. The liquid injection device 1B of this example is similar to the liquid injection device 1A of Example 1 except for the configuration described below. Therefore, the liquid injection device 1B of this example has the same characteristics as the liquid injection device 1A of Example 1 except for the points described below. Therefore, in FIG. 2, components common to Example 1 are indicated by the same reference numerals, and detailed descriptions will be omitted.

As shown in FIG. 1, the liquid injection device 1A of the first embodiment includes a flow path switching unit 9A having a switching lever 11 as the flow path switching unit 9. On the other hand, as shown in FIG. 2, the liquid injection device 1B of the present embodiment does not include the switching lever 11 as the flow path switching unit 9, and instead includes a flow path switching unit 9B electrically connected to the control unit 5 by a control signal line 51.

That is, the liquid injection device 1B of this embodiment is equipped with a control unit 5 that controls the opening and closing of the first flow path 7b and the second flow path 7c of the flow path switching unit 9B. Therefore, the liquid injection device 1B of this embodiment is configured to eliminate the need for the user to manually switch between opening and closing the first flow path 7b and the second flow path 7c of the flow path switching unit 9. Note that although the flow path switching unit 9B of this embodiment is a solenoid valve, an air-operated three-way valve may be used instead of the solenoid valve.

[Example 3]
A liquid injection device 1C of Example 3 will be described below with reference to Fig. 3. Fig. 3 is a diagram corresponding to Fig. 1 showing the liquid injection device 1A of Example 1. The liquid injection device 1C of this example is similar to the liquid injection device 1B of Example 2 except for the configuration described below. Therefore, the liquid injection device 1C of this example has the same features as the liquid injection device 1 of Examples 1 and 2 except for the points described below. Therefore, in Fig. 3, components common to Examples 1 and 2 are indicated by the same reference numerals, and detailed descriptions are omitted.

As shown in FIG. 3, the liquid ejection device 1C of this embodiment has a storage section 12 that stores the head section 2 when not in use. As shown in FIG. 3, the storage section 12 is arranged so as to be located above the liquid level 3F of the liquid 3 stored in the liquid storage section 8 in the direction of gravity. Therefore, the liquid ejection device 1C of this embodiment is configured to prevent the liquid 3 from leaking out of the head section 2 stored in the storage section 12.

[Example 4]
A liquid injection device 1D of Example 4 will be described below with reference to Fig. 4. Fig. 4 is a diagram corresponding to Fig. 1 showing the liquid injection device 1A of Example 1. The liquid injection device 1D of this example is similar to the liquid injection device 1B of Example 2 except for the configuration described below. Therefore, the liquid injection device 1D of this example has similar features to the liquid injection devices 1 of Examples 1 to 3 except for the points described below. Therefore, in Fig. 4, components common to Examples 1 to 4 are indicated by the same reference numerals, and detailed descriptions will be omitted.

As shown in Figures 1 to 3, in the liquid injection device 1 of Examples 1 to 3, the flow path switching unit 9 was configured to be connected to three flow paths 7: the upstream flow path 7a, the first flow path 7b, and the second flow path 7c. In other words, in the liquid injection device 1 of Examples 1 to 3, the flow path switching unit 9 was a three-way valve. By configuring the flow path switching unit 9 as a three-way valve, the configuration of the flow path switching unit 9 itself can be simplified. Furthermore, by simplifying the configuration of the flow path switching unit 9, it is possible to achieve a smaller device and lower costs.

On the other hand, as shown in FIG. 4, in the liquid ejection device 1D of this embodiment, the flow path switching unit 9C is connected to the upstream flow path 7a, the first flow path 7b, the second flow path 7c, and the third flow path 7d that leads to the liquid recovery container 13. That is, in the liquid ejection device 1D of this embodiment, the flow path switching unit 9C is connected to the flow path through which the liquid 3 flows through four ports. In this way, the flow path switching unit 9 is not limited to three ports to the flow path 7 through which the liquid 3 flows, and may be connected to four or more ports. As in the liquid ejection devices 1 of Examples 1 to 4, as long as the flow path switching unit 9 is connected to the flow path 7 through which the liquid 3 flows through three or more ports, at least the first flow path 7b and the second flow path 7c can be easily formed.

The present invention is not limited to the above-mentioned embodiments, and can be realized in various configurations without departing from the spirit of the present invention. The technical features in the embodiments corresponding to the technical features in each aspect described in the Summary of the Invention column can be replaced or combined as appropriate to solve some or all of the above-mentioned problems or to achieve some or all of the above-mentioned effects. Furthermore, if a technical feature is not described as essential in this specification, it can be deleted as appropriate.

1...Liquid ejection device, 1A...Liquid ejection device, 1B...Liquid ejection device, 1C...Liquid ejection device, 1D...Liquid ejection device, 2...Head section, 3...Liquid, 3a...Continuous flow, 3b...Liquid droplet, 3F...Liquid surface, 5...Control section, 6...Liquid delivery section, 7...Flow path, 7a...Upstream flow path, 7b...First flow path, 7c...Second flow path, 7d...Third flow path, 8...Liquid storage section, 9...Flow path switching section, 9A...Flow path switching section, 9B...Flow path switching section, 9C...Flow path switching section, 10...Connection section, 11...Switch lever, 12...Storage section, 13...Liquid collection container, 27...Nozzle, 51...Control signal line, 52...Control signal line

Claims (9)

a liquid storage section for storing liquid;
a head unit having a nozzle for spraying the liquid in a continuous stream and converting the continuous stream into droplets for impacting the droplets on an object;
a liquid delivery unit that delivers the liquid from the liquid storage unit to the head unit;
a first flow path through which the liquid flows, one end of which is connected to the liquid delivery section and the other end of which is connected to the head section;
a second flow path through which the liquid flows and one end of which is connected to the first flow path;
a flow path switching unit disposed at a connection portion between the first flow path and the second flow path,
The flow path switching unit is
When the liquid is ejected from the head portion, the first flow path is opened and the second flow path is closed.
a head unit configured to receive the liquid from the head and to eject the liquid from the head unit; 2. The liquid ejection apparatus according to claim 1,
The other end of the second flow path is connected to the liquid storage portion. 3. The liquid ejection apparatus according to claim 1,
A liquid ejecting apparatus comprising: a control unit that controls opening and closing of the first flow path and the second flow path of the flow path switching unit. 2. The liquid ejection apparatus according to claim 1,
The liquid ejecting device according to claim 1, wherein the second flow path is located above a liquid level of the liquid stored in the liquid storage portion in a direction of gravity. The liquid ejection apparatus according to claim 4 ,
The other end of the second flow path is connected to the liquid storage portion,
a connection portion between the second flow path and the liquid storage portion, the connection portion being located above a liquid level of the liquid stored in the liquid storage portion in a direction of gravity. 3. The liquid ejection apparatus according to claim 1,
The liquid ejecting device is configured so that the pressure in the second flow path becomes lower than atmospheric pressure when ejection of the liquid from the head portion is stopped. 3. The liquid ejection apparatus according to claim 1,
A housing portion that houses the head portion is provided,
The liquid ejecting apparatus according to claim 1, wherein the container is located above a liquid level of the liquid stored in the liquid storage portion in a direction of gravity. 3. The liquid ejection apparatus according to claim 1,
The liquid ejecting apparatus according to claim 1, wherein the flow path switching unit is connected to the flow path through which the liquid flows through three or more ports. 9. The liquid ejection apparatus according to claim 8,
The liquid ejecting apparatus according to claim 1, wherein the flow passage switching unit is a three-way valve.

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