JP2010131493A - Liquid discharge apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To give three states of pressurizing, suction and opening to atmosphere to a syringe while reducing the number of stop valves to be used. <P>SOLUTION: The liquid discharge apparatus includes the syringe 10 in which a liquid is filled and an air pressure source 12 for discharging the filled liquid from the tip part by supplying pressurized air to the syringe. A suction port 14C of an ejector 14 having negative pressure generation function is connected to the syringe, an air feed port 14A of the ejector is connected to the air pressure source. An air supply stop valve 18 and an evacuation stop valve 20 are respectively arranged between the air pressure source and the air supply port of the ejector and in the exit side of the discharge port 14B of the ejector. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a liquid ejecting apparatus, and more particularly to a suitable liquid ejecting apparatus adapted for applying an adhesive to an electronic substrate.

  2. Description of the Related Art In a surface mounting apparatus that mounts electronic components on an electronic substrate, double-sided mounting in which components are mounted on both surfaces of the substrate is generally performed.

  In this double-sided mounting process, the mounted electronic component is generally fixed with an adhesive so that the electronic component does not fall when the substrate is turned over. Therefore, an adhesive application device (liquid ejection device) has been conventionally used to apply an adhesive to a predetermined position of the substrate.

  As such an adhesive application device, for example, Patent Document 1 includes a pressurization source, a negative pressure source, and an air release port in order to create three states of pressurization, suction, and air release. By providing three ON / OFF circuits to control and switching each, a syringe filled with adhesive is supplied with a positive pressure and discharged, and a negative pressure is supplied to reduce the residual pressure at the time of discharge. A material that has been applied by a series of operations of rapid removal and then opening to the atmosphere is disclosed.

JP 2006-192371 A

  However, the adhesive application device disclosed in Patent Document 1 includes three states: positive pressure supply (pressurization), negative pressure supply (suction), and air release to a syringe that discharges the filled adhesive. In order to produce the above, since the on-off valves are individually provided for the positive pressure source, the negative pressure source, and the atmosphere opening port, there is a problem that a total of three on-off valves are required.

  The present invention has been made to solve the above-mentioned conventional problems. The number of on-off valves to be used is reduced, and the three states of pressurization, suction, and air release are reliably realized with respect to the syringe. It is an object of the present invention to provide a liquid ejection device that can perform the above-described process.

  The present invention relates to a liquid discharge apparatus comprising a syringe for filling a liquid and a pneumatic pressure source for supplying pressurized air to the syringe and discharging the filled liquid from a tip portion. A suction port of an ejector having a pressure generating function, an air supply port of the ejector are connected to the air pressure source, and an air supply on / off valve is connected between the air pressure source and the air supply port of the ejector, The above problems are solved by providing an exhaust opening / closing valve on the outlet side of the exhaust port of the ejector.

  The present invention also opens the air supply on / off valve, closes the exhaust on / off valve to discharge liquid, and opens the exhaust on / off valve to suck the residual pressure in the syringe while the air supply on / off valve is open. Control means for controlling a discharge operation including a step and a step of closing the air supply on / off valve and opening the inside of the syringe to the atmosphere while the exhaust on / off valve is open may be provided.

  According to the present invention, when the high-pressure air supplied from the air supply port is discharged from the exhaust port between the air pressure source that is the pressurization source and the syringe, the negative pressure can be generated in the suction port. Since an ejector having a function is provided, an air supply on / off valve is provided on the inlet side of the air supply port, and an exhaust on / off valve is provided on the outlet side of the exhaust port. By switching appropriately, three states of pressurization, suction, and release to the atmosphere can be reliably created in the syringe. Therefore, since it was possible to reduce the number of three on-off valves that were conventionally required to achieve this to two, the cost of the solenoid valve can be reduced to 2/3 compared to the existing method. did it.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  In FIG. 1, the outline | summary of the pneumatic circuit which comprises the principal part of the adhesive agent coating apparatus of one Embodiment which concerns on this invention is shown.

  The adhesive application device (liquid ejection device) of this embodiment is mounted on a head (not shown) that is moved up and down by a Z-axis drive mechanism, and is filled with an adhesive (liquid); A pneumatic pressure source 12 composed of a compressor or the like is provided to supply pressurized air through the pipe to the syringe 10 and discharge the filled adhesive from the tip.

  In this adhesive application device, an ejector (ejector-type vacuum generator) 14 having a negative pressure generating function is interposed between the syringe 10 and the air pressure source 12. When the pressurized air supplied to the air supply port 14A is discharged from the exhaust port 14B, the ejector 14 can generate a negative pressure at the suction port 14C.

  In this embodiment, the suction port 14C of the ejector 14 is connected to the syringe 10, and the air supply port 14A of the ejector 14 is connected to the air pressure source 12 via the pressure regulator 16 that adjusts the air pressure. Has been.

  An air supply opening / closing valve 18 is disposed between the air pressure source 12 and the air supply port 14A of the ejector 14 separately from the pressure regulator 16, and on the outlet side of the exhaust port 14B of the ejector 14. An exhaust on / off valve 20 is provided, and the exhaust on / off valve 20 communicates with the atmosphere side through a silencer 22. A pressure gauge 24 for detecting the pressure in the pipe is attached to the pipe connecting the syringe 10 and the suction port 14C of the ejector 14.

  In the present embodiment, the air supply on / off valve 18 and the exhaust on / off valve 20 are both composed of electromagnetic valves, and the control unit (control means) 26 controls the opening / closing operation of each electromagnetic valve with respect to the solenoid. Yes.

  Specifically, the control unit 26 opens the air supply opening / closing valve 18 and closes the exhaust air opening / closing valve 20, whereby the positive pressure supplied to the air supply port 14 </ b> A is supplied to the syringe 10 via the suction port 14 </ b> C. The step of introducing the adhesive and discharging the adhesive and opening the exhaust on / off valve 20 with the air supply on / off valve 18 open to enable the negative pressure generating function of the ejector 14 to enable exhaust from the suction port 14C. High pressure air is guided to the port 14B, the residual pressure in the syringe 10 is sucked and removed rapidly, and the air supply opening / closing valve 18 is closed while the exhaust opening / closing valve 20 is open, thereby opening the inside of the syringe 10 to the atmosphere. Control to execute the step to perform.

  The operation of the present embodiment having the above configuration will be described with reference to the time chart of FIG. 4 according to the flowcharts of FIGS.

  First, at step 0, the on-off valve is initialized. Specifically, as shown in the subroutine of FIG. 3, the pressurization on-off valve (air supply on-off valve) 18 is closed, the exhaust on-off valve 20 is opened, and the inside of the syringe 10 is opened to the atmosphere. Set to the initial state.

  After the initialization of the on-off valve is completed, the operation of the coating loop from step 1 to step 13 is executed a specified number of times.

  Specifically, the head (not shown) to which the syringe 10 is attached is moved to the application position (step 1), and the exhaust on-off valve 20 is closed at timing t1 (step 2).

  Next, the head starts to be lowered by the Z-axis motor at timing t2 (step 3), and after waiting for a preset specified time (step 4), the pressurization on / off valve 18 is opened at timing t3 (step 5).

  Thereafter, after waiting for a specified time (step 6), the exhaust on-off valve 20 is opened at timing t4 (step 7), and after waiting for a further specified time (step 8), the pressurizing on-off valve is closed at timing t5 (step 9). The head descent is completed at timing t6 (step 10). Thereafter, after waiting for a specified time (step 11), the head ascent is started at timing t7 (step 12), and when the head ascent is completed, one coating operation is terminated (step 13).

  In the present embodiment, as shown in FIG. 4 as a change over time in the pressure in the syringe, in the process of sucking the residual pressure in the syringe, it is difficult to stop the suction in a state where the atmospheric pressure is exactly equal each time. Therefore, after the suction operation, the atmosphere is released to the atmosphere at timing t5, thereby preventing the leakage of the adhesive and the drawing into the syringe.

  According to the present embodiment described in detail above, the exhaust on-off valve 20 is closed and the pressurization on-off valve 18 is opened to supply the air supply port 14A of the ejector 14 as shown in FIG. 5A. Since the pressurized air thus introduced is introduced into the syringe 10 via the suction port 14C of the ejector 14, the adhesive inside the syringe 10 can be discharged from its tip. In the figure, 10A represents a float, L represents an adhesive, and S represents a substrate.

  Further, by opening the exhaust on-off valve 20 while the pressurization on-off valve 18 is open, the suction port of the ejector 14 is utilized by utilizing the negative pressure generating function of the ejector 14 as shown in FIG. 5B. The pressurized air in the syringe 10 can be sucked into the exhaust port 14B from 14C.

  Furthermore, by closing the air supply opening / closing valve 18 at the timing when the residual pressure in the syringe 10 is exhausted, the inside of the syringe 10 can be opened to the atmosphere as shown in FIG. Since it is possible to return to the initial state before the discharge, it is possible to start the next discharge operation because preparation for a new discharge is completed.

  Therefore, since only three open / close valves are used, the three states of positive pressure, negative pressure, and open to the atmosphere can be quickly switched in the syringe 10, so that efficient application of the adhesive can be realized.

Pneumatic circuit diagram showing the main part of an adhesive application device according to an embodiment of the present invention The flowchart which shows the procedure of the liquid discharge operation | movement by the adhesive agent coating apparatus of this embodiment. Flow chart showing an initialization loop of the on-off valve that is performed during the liquid discharge operation Time chart showing the time lapse of the liquid discharge operation by the adhesive application device of this embodiment Explanatory drawing which shows the image at the time of the liquid discharge by this embodiment Explanatory drawing which shows the image at the time of rapid removal of the residual pressure by this embodiment Explanatory drawing which shows the image at the time of air release by this embodiment

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Syringe 12 ... Air pressure source 14 ... Ejector 14A ... Air supply port 14B ... Exhaust port 14C ... Suction port 16 ... Pressure regulator 18 ... Air supply (pressurization) on-off valve 20 ... Exhaust on-off valve 22 ... Silencer 24 ... Pressure gauge 26 ... Control unit

Claims (2)

In a liquid ejection apparatus comprising a syringe for filling a liquid, and an air pressure source for supplying pressurized air to the syringe and ejecting the filled liquid from a tip portion,
The syringe has a suction port of an ejector having a negative pressure generating function,
An air supply port of the ejector is connected to the air pressure source,
An air supply on / off valve is provided between the air pressure source and the air supply port of the ejector.
2. A liquid discharge apparatus according to claim 1, wherein an exhaust opening / closing valve is provided on the outlet side of the exhaust port of the ejector.   Opening the air supply on / off valve and closing the exhaust air on / off valve to discharge liquid; opening the air supply on / off valve and opening the exhaust on / off valve to suck the residual pressure in the syringe; and the exhaust on / off valve The liquid discharge apparatus according to claim 1, further comprising a control unit that controls a discharge operation including a step of closing the air supply on / off valve and opening the inside of the syringe to the atmosphere while the valve is open.

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