JP2021074669A - Air type dispenser - Google Patents

Abstract

To provide an air type dispenser that can highly accurately detect a residual quantity of a material in a syringe.SOLUTION: A syringe 7 discharges a material 12 when being fed with dry air. A valve 4 switches between feeding dry air into the syringe 7 and evacuating dry air from the syringe 7. A flow meter 6 measures a flow rate of dry air evacuated from the syringe 7. A residual quantity detection part 8 detects a residual quantity of a material in the syringe 7 by comparing a measurement value of the flow meter 6 to a threshold.SELECTED DRAWING: Figure 1

Description

The present invention relates to an pneumatic dispenser.

In an air dispenser, when dry air is supplied to the syringe, the syringe ejects the material. Conventionally, the pressure in the syringe is compared with the threshold value to detect the remaining amount of the material in the syringe (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 10-128208

However, the pressure inside the syringe is affected by the expansion of the syringe or the pressure loss from the fittings through which air flows. Therefore, it was not possible to detect the remaining amount of the material inside the syringe with high accuracy.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to obtain an air-type dispenser capable of detecting the remaining amount of a material inside a syringe with high accuracy.

The air-type dispenser according to the present invention includes a syringe that discharges a material when dry air is supplied, a valve that switches between supplying the dry air to the syringe and exhausting the dry air from the syringe, and the syringe. It is characterized by including a flow meter for measuring the flow rate of the dry air exhausted from the syringe and a remaining amount detecting unit for detecting the remaining amount of the material inside the syringe by comparing the measured value of the flow meter with a threshold value. And.

In the present invention, the flow rate of dry air exhausted from the syringe is measured, and the measured value is compared with a threshold value to detect the remaining amount of material inside the syringe. Here, the pressure inside the syringe changes due to the expansion of the syringe or the pressure loss from the joints, but the flow rate of dry air is not affected by the pressure inside the syringe. Therefore, the remaining amount of the material inside the syringe can be detected with high accuracy.

It is the schematic which shows the air type dispenser which concerns on Embodiment 1. FIG. It is the schematic which shows the side surface of a syringe. It is the schematic which shows the side surface of a syringe. It is a flowchart of the operation of the air type dispenser which concerns on Embodiment 1. FIG. It is a flowchart of the operation of the air type dispenser which concerns on Embodiment 2. It is a flowchart of the operation of the air type dispenser which concerns on Embodiment 3. It is a flowchart of the operation of the air type dispenser which concerns on Embodiment 4.

The pneumatic dispenser according to the embodiment will be described with reference to the drawings. The same or corresponding components may be designated by the same reference numerals and the description may be omitted.

Embodiment 1.
FIG. 1 is a schematic view showing an air-type dispenser according to the first embodiment. This air-type dispenser is a semiconductor manufacturing device used for manufacturing a semiconductor device. The air-type dispenser is contained in a box made by bending ordinary steel (SPCC) to prevent the exposure of each equipment.

The air supply port 1 and the pressure adjusting regulator 2 are connected to each other via a polyurethane tube 3a. The pressure adjusting regulator 2 and the solenoid valve 4 are connected via a polyurethane tube 3b. The solenoid valve 4 and the exhaust port 5 are connected via a polyurethane tube 3c. The solenoid valve 4 and the flow meter 6 are connected via a polyurethane tube 3d. The flow meter 6 and the syringe 7 are connected via a polyurethane tube 3e. The polyurethane tubes 3a to 3e are made of polyurethane and have an outer diameter of 6 mm and an inner diameter of 4 mm.

The CPU board 8 and the D / A converter 9 are electrically connected via a signal transmission line 10a. The D / A converter 9 and the pressure adjustment regulator 2 are electrically connected via a signal transmission line 10b. The CPU board 8 and the solenoid valve 4 are electrically connected via a signal transmission line 10c. The flow meter 6 and the A / D converter 11 are electrically connected via a signal transmission line 10d. The A / D converter 11 and the CPU board 8 are electrically connected via a signal transmission line 10e.

2 and 3 are schematic views showing the side surfaces of the syringe. The material of the syringe 7 is polypropylene. The material 12 is filled inside the syringe 7. The material 12 is, for example, an Ag paste for joining a semiconductor element onto a lead frame. When the dry air is supplied from the upper opening, the syringe 7 discharges the material 12 from the lower opening. FIG. 2 shows a state of 100% material filling, and FIG. 3 shows a state of 30% material filling.

The air supply port 1 is configured to take in dry air from an external dry air generator (not shown) or the like and supply it into the dispenser. The pressure adjusting regulator 2 adjusts the pressure (kPa) of the dry air supplied from the air supply port 1. However, the pressure adjusting regulator 2 has a depressurizing function for reducing the pressure of the dry air, but does not have a boosting function. The pressure of the dry air decompressed by the pressure adjusting regulator 2 is displayed on the digital pressure gauge 13.

The solenoid valve 4 is a valve having a three-way valve structure, and the valve is opened and closed by a control signal transmitted from the CPU board 8 via a signal transmission line 10c. When the control signal transmitted from the CPU board 8 to the solenoid valve 4 is less than a predetermined voltage as a non-energized signal, for example, 0 V, the inside of the valve is connected so that the flow meter 6 side and the exhaust port 5 side are connected as a path. The valve works. This state is called "closed state". When the control signal transmitted from the CPU board 8 to the solenoid valve 4 is equal to or higher than a predetermined voltage as an energization signal, for example, 5 V, the inside of the valve is connected so that the air supply port 1 side and the flow meter 6 side are connected as a path. The valve works. This state is called "open state". The solenoid valve 4 switches between an open state in which dry air is supplied to the syringe 7 and a closed state in which dry air is exhausted from the syringe 7.

The discharge amount can be adjusted by adjusting the pressure adjusting regulator 2 so that the pressure becomes the set pressure. The discharge amount can also be adjusted by adjusting the open state time of the solenoid valve 4. The pressure set by the pressure adjusting regulator 2 and the open state time of the solenoid valve 4 are set to optimum values according to the characteristics of the material 12 and the tact time at the time of manufacturing the product.

The CPU board 8 outputs a binary (1 or 0) digital signal. The D / A converter 9 converts a digital signal into an analog signal. The pressure adjusting regulator 2 adjusts the pressure adjusting valve in response to this analog signal.

The portion of the syringe 7 in contact with dry air changes according to the remaining amount of the material 12 inside the syringe 7. The syringe 7 expands at the portion where the dry air comes into contact. Therefore, the flow rate of the dry air discharged from the syringe 7 changes according to the remaining amount of the material 12 inside the syringe 7. Therefore, in the present embodiment, the flow meter 6 measures the flow rate (L / min) of the dry air discharged from the syringe 7. The flow meter 6 outputs the measured value as an analog signal. The A / D converter 11 converts an analog signal into a binary (1 or 0) digital signal. The CPU board 8 inputs a digital signal to read the flow rate of dry air.

The flow rates of dry air in the state of 100% material filling shown in FIG. 2 and the state of 30% material filling shown in FIG. 3 are measured in advance and set as threshold values on the CPU substrate 8. The CPU board 8 is a remaining amount detecting unit that detects the remaining amount of the material 12 inside the syringe 7 by comparing the measured flow rate of dry air with a threshold value.

FIG. 4 is a flowchart of the operation of the air type dispenser according to the first embodiment. The pressure adjusting regulator 2 decompresses the dry air, and the CPU board 8 transmits a control signal to the solenoid valve 4 for a predetermined time to open the valve (step S1). When in the open state, dry air is supplied to the syringe 7 through the flow meter 6. The material 12 in the syringe 7 is pumped and discharged by the supplied dry air (step S2). The discharge amount is adjusted by the pressure of the dry air decompressed by the pressure adjusting regulator 2 and the open state time of the solenoid valve 4.

The solenoid valve 4 is closed to complete the discharge operation (step S3). At the moment when the solenoid valve 4 is closed, the flow meter 6 side and the exhaust port 5 side are connected as a path. Then, the dry air remaining inside the syringe 7 and the polyurethane tubes 3d and 3e is exhausted from the exhaust port 5 (step S4).

The flow meter 6 measures the flow rate of the dry air exhausted from the syringe 7 (step S5). The measured value of the flow meter 6 is converted into a digital signal by the A / D converter 11 and transmitted to the CPU board 8 (step S6). The CPU board 8 compares the measured value of the flow rate of dry air with a predetermined threshold value (step S7), and detects the remaining amount of the material 12 inside the syringe 7 (step S8). Here, the pressure inside the syringe 7 changes due to the expansion of the syringe 7 or the pressure loss from the joints, but the flow rate of the dry air is not affected by the pressure inside the syringe 7. Therefore, the remaining amount of the material 12 inside the syringe 7 can be detected with high accuracy.

As a result of detecting the remaining amount, if the syringe 7 contains sufficient material, the CPU board 8 does not issue a warning alarm. On the other hand, when the material in the syringe 7 is about to run out, the CPU board 8 issues a warning alarm. As a result, the material 12 can be used without waste, and the amount of waste of the material 12 can be reduced.

Embodiment 2.
FIG. 5 is a flowchart of the operation of the air type dispenser according to the second embodiment. In the present embodiment, the configuration of the air-type dispenser is the same as that in the first embodiment, except that the flow rate of the dry air supplied to the syringe 7 is measured.

The CPU board 8 transmits a control signal to the solenoid valve 4 for a predetermined time to open the valve (step S1). At this time, the flow meter 6 measures the flow rate of the dry air supplied to the syringe 7 (step S9). The measured value of the flow meter 6 is converted into a digital signal by the A / D converter 11 and transmitted to the CPU board 8 (step S10). The CPU board 8 compares the measured value of the flow rate of dry air with a predetermined threshold value (step S11). As a result, the remaining amount of the material 12 inside the syringe 7 is detected (step S12).

Then, as in the first embodiment, the material 12 in the syringe 7 is pumped and discharged by the supplied dry air (step S2). When the set discharge operation is completed, the solenoid valve 4 is closed (step S3). The dry air remaining inside the syringe 7 and the polyurethane tubes 3d and 3e is exhausted from the exhaust port 5 (step S4).

As described above, in the present embodiment, the flow rate of the dry air supplied to the syringe 7 for pressurizing the inside of the syringe 7 and discharging the material 12 is measured. As a result, the measured value of the flow meter 6 can be acquired earlier than that of the first embodiment, so that the calculation processing time of the CPU board 8 can be secured. Therefore, since there is no waiting for treatment of the CPU board 8 at the time of continuous discharge, the discharge interval can be shortened and the tact time is improved. Other configurations and effects are the same as those in the first embodiment.

Embodiment 3.
FIG. 6 is a flowchart of the operation of the air type dispenser according to the third embodiment. In the present embodiment, the configuration of the pneumatic dispenser is the same as that of the first embodiment, and a step of adjusting the pressure of the dry air is added to the operation of the second embodiment.

Here, the polyurethane tubes 3a to 3e and the syringe 7 expand due to pressure. The expansion coefficient of the syringe 7 increases as the surface area of the syringe 7 increases. As the material 12 in the syringe 7 disappears, the surface area increases and the expansion rate increases. When the expansion rate becomes high, the pressure applied to the material 12 in the syringe 7 decreases, and the discharge amount decreases. As the remaining amount of the material 12 in the syringe 7 decreases, the discharge amount decreases at the same discharge pressure and the same discharge time. This phenomenon is called head difference.

Therefore, in the present embodiment, the pressure adjusting regulator 2 automatically increases the pressure of the dry air supplied to the syringe 7 as the remaining amount of the material 12 inside the detected syringe 7 decreases (step S13). As a result, it is possible to suppress variations in the discharge amount due to the head difference and keep the discharge amount constant. Other configurations and effects are the same as in the second embodiment.

Embodiment 4.
FIG. 7 is a flowchart of the operation of the air type dispenser according to the fourth embodiment. In the present embodiment, the configuration of the air-type dispenser is the same as that in the first embodiment, and a step of adjusting the supply time of dry air is added to the operation of the third embodiment.

Similar to the third embodiment, the pressure adjusting regulator 2 automatically increases the pressure of the dry air supplied to the syringe 7 as the remaining amount of the material 12 inside the detected syringe 7 decreases (step S13). Further, as the remaining amount of the material 12 inside the detected syringe 7 decreases, the electromagnetic solenoid valve 4 prolongs the time for supplying dry air to the syringe 7. As a result, it is possible to suppress variations in the discharge amount due to the head difference and keep the discharge amount constant. Further, although it is difficult to finely adjust the pressure in the syringe 7 to reach the set value, it is possible to avoid fine adjustment of the pressure by lengthening the time for supplying dry air. Other configurations and effects are the same as in the third embodiment.

2 Pressure regulator, 4 Solenoid solenoid valve (valve), 6 Flow meter, 7 Syringe, 8 CPU board (remaining amount detector), 12 Material

Claims (4)

A syringe that discharges material when dry air is supplied,
A valve that switches between supplying the dry air to the syringe and exhausting the dry air from the syringe.
A flow meter that measures the flow rate of the dry air exhausted from the syringe, and
An air-type dispenser including a remaining amount detecting unit that detects a remaining amount of the material inside the syringe by comparing a measured value of the flowmeter with a threshold value. A syringe that discharges material when dry air is supplied,
A valve that switches between supplying the dry air to the syringe and exhausting the dry air from the syringe.
A flow meter that measures the flow rate of the dry air supplied to the syringe, and
An air-type dispenser including a remaining amount detecting unit that detects a remaining amount of the material inside the syringe by comparing a measured value of the flowmeter with a threshold value. The air-type dispenser according to claim 2, further comprising a pressure adjusting regulator that raises the pressure of the dry air supplied to the syringe as the remaining amount of the material inside the syringe that is detected decreases. The air-type dispenser according to claim 2 or 3, wherein the valve prolongs the time for supplying the dry air to the syringe as the remaining amount of the material inside the syringe that is detected decreases.

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