JPH0449108A - Screw type discharge device - Google Patents

Abstract

PURPOSE:To permit discharge of fluid in a fixed quantity, with high precision, consecutively and uniformly without being influenced by the viscosity of the fluid, the fluidity or the amount of fluid in a barrel but removing the influence of the foam by providing a screw, which extracts the fluid in a container from a discharge opening and moves to the second discharge opening, and a control device to control the rotation of the driving structure of the screw. CONSTITUTION:With a signal from a sensor 30, a control device body 32 output a set pressure value designated signal for a pressure setting device 22 to a servo amplification circuit 42 which supplies the specified voltage to a motor 44 to drive it. When the motor 44 sends compressed air in an air pump 46 to the upper portion of the fluid in a barrel 4, a pressure sensor 48 detects it and the compressed air is returned to the circuit 42. Consequently, the upper portion of the fluid in the barrel 4 is constantly supplied with a fixed pressure set by the setting device 22. When the device body 32 outputs a rotating speed signal of a motor 8 to a servo amplification circuit 34 by a signal from the sensor 30, the circuit 34 responding to the input signal applies the specified voltage to the motor 8 to drive it. Next, the motor 8 drives a screw 12 and discharges a fixed amount of fluid coming through a piping 18 into a specified container through a second discharge opening 6.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a dispensing device for dispensing and dispensing a fluid in a fixed amount, and particularly to a dispensing device that can stably dispense and dispense a predetermined amount of fluid with high precision. Regarding.

[Prior Art] A conventional dispensing device for dispensing and dispensing a fluid in a quantitative manner generally stores the fluid in a cylindrical container (hereinafter referred to as a barrel) that has a narrow discharge opening at one end and is open at the other end. A plunger that slides inside the container is pushed through the opening by a piston, and the stored fluid is pressurized and discharged at a constant rate.

[Problem to be solved by the invention] By the way, according to the conventional dispensing method, it is difficult to move the piston with high precision, and in particular, it is difficult to move the piston with high viscosity due to the stars of the fluid present in the barrel. The pressure varies greatly, and there is also the risk of air being mixed in and causing foaming, making it difficult to discharge while running correctly.

Purpose of the Invention] Therefore, the present invention solves the above-mentioned disadvantages, eliminates the influence of the viscosity and fluidity of the fluid, and the amount of fluid in the barrel, and eliminates the influence of bubbles to accurately quantify the amount of fluid. The object of the present invention is to realize a fluid ejecting device that is capable of continuously and uniformly ejecting fluid.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the screw type discharge device of the present invention includes a fluid container provided with a discharge port, and a second fluid container that extracts the fluid in the container from the discharge port. The invention is characterized in that it includes a screw that moves to the discharge port, a screw drive mechanism, and a control device that controls the rotation of the screw drive mechanism.

[Function] With the above-mentioned configuration, when discharging fluid, the viscosity and fluidity of the fluid can be controlled by controlling the rotational speed of the screw corresponding to the structural dimensions of the screw and the timing of stopping with high precision by the control device. It does not affect the amount of fluid inside the barrel. In addition, since the fluid is pumped by a screw, the influence of bubbles can be removed, and even in continuous discharge, the amount of fluid discharged is stabilized and a fixed amount of fluid is discharged.

[Example code] The present invention will be described in detail below based on the drawings.

Figure 1 shows a schematic side view of the screw type discharge device according to the present invention, and Figure 2 shows the side view of the fluid container (hereinafter referred to as barrel) and motor section in the screw type discharge device shown in Figure 1. It is the mouth. Further, FIG. 3 is a schematic block diagram of a control circuit in a schematic example of the screw type discharge device shown in FIG. 1, and FIG. 4 is a schematic block diagram of a circuit according to another control method.

In FIG. 1, 2 is an I11 control device whose details will be described later, 22 is a pressure setting device for applying pressure from the back of the fluid when discharging fluid, and 24 is the rotation of a screw that determines the discharge amount per unit time when discharging fluid. A speed setting device 26 is a timer setting device for setting the fluid ejection time and controlling the fluid ejection amount when discharging the fluid.9 Also, 4 is a barrel for storing the fluid to be ejected, and 6 is the number 1 as described in the claims. 2 outlet,
8 is a motor, 8a is an electric cable connecting the control device 2 and the motor 8, 10 is a mechanical unit containing a screw, the details of which will be described later, and the motor 8 has a rotation speed determined by the setting value of the rotation speed setting device 24. The barrel 4 rotates to drive and rotate a screw (to be described later) installed inside the time mechanism section 10, which is set by a timer setter 26, and a fixed amount of fluid stored in the barrel 4 is discharged from the second discharge port 6.

At this time, according to the viscosity of the fluid, the pressure setting device 22
Apply back pressure to the fluid at a pressure set by

4a is a pressure air pipe for transmitting the back pressure to the barrel.

In the 2nd I21, 4 and 8 are respectively the 1st [21
9, there is a barrel and a motor as mentioned above, 10 is the mechanism part 6, which is the second discharge port, 9 is a mechanism part 10, a screw 12 for moving the filled fluid by rotation, and an air Special boats 1, 4. The barrel discharge port 16 described in the claims and the pipe 18 connecting the discharge port 16 and the screw 12 are installed, and on the opposite side of the pipe 8 from the discharge port 16, the pipe 18 is cleaned, etc. A boat 18a is provided that can be opened when necessary.

In the above-mentioned configuration diagram, description of functional elements that are not directly related to the explanation of the present invention, such as a container to which a predetermined fluid is discharged by the present screw-type discharge device and a movement drive mechanism for the container, is omitted.

In FIG. 3, 22, 24, and 26 respectively indicate the pressure setting device, rotation speed setting device, and timer setting device described above in FIG.

Further, 30 is a sensor that confirms the presence of a partner container to which a predetermined fluid is to be discharged and distributed from the discharge device and obtains a signal to start discharge.

Reference numeral 32 denotes a control device main body, which is composed of an electronic circuit having predetermined functions. 34 is a servo amplifier circuit that drives the motor 8, and the control device main body 3 that converts each setting value mentioned above and outputs it as a command value of the motor rotation speed.
The motor 8 is started or stopped according to the signal from the motor 2, and the rotational speed is controlled.

The motor 8 is a DC motor, and is driven and controlled by a water amplification motor 34, and rotates the screw 12 at a predetermined speed for a predetermined time via a power transmission gear mechanism ([2I not shown)] to generate fluid. Dispense a fixed amount.

38 is a tachometer for detecting the rotational speed of the motor, and the detected value is returned to the servo amplifier circuit 34. The servo amplification circuit 34 compares the detected value with a signal output from the control device main body 32, and outputs the signal so that the deviation becomes zero to control the rotation of the motor 8 and maintain stable rotation of the screw 12.

Reference numeral 44 denotes a DC motor, and includes an air pump 46 that generates pressurized air to apply a predetermined back pressure to the upper part of the fluid inside the barrel via the piping 4a, as described above in the explanation of FIG. , gear mechanism for power transmission (not shown)
Drive through.

42 is a servo amplifier circuit that drives the motor 44,
The motor drive power is output in accordance with a signal from the control device body 32 which converts the pressure setting value set by the pressure setting device 22 and outputs it as an air pressure command value, starts or stops the rotation of the motor 44, and , to control the rotation speed.

A pressure sensor 48 detects the pressure obtained by the air pump 46, and the detected value of the pressure sensor 48 is returned to the servo amplifier circuit 42. The servo amplifier circuit 42 compares the detected value with the signal output from the control device main body 32,
The rotation of the motor 44 is controlled by outputting so that the deviation becomes zero, and the output air pressure of the air pump is maintained at the set value.

In the above block diagram, circuit elements that are not directly necessary for the explanation of the present invention are omitted, such as a power supply circuit, a power switch, a start/stop switch for the dispensing function, and a signal circuit that outputs a dispensing completion signal. There is.

Next, the operation in the above configuration will be explained.

When the fluid to be discharged and distributed by the screw type discharge device is determined, the rotation speed of the motor is set to determine the rotation speed of the screw 12 in accordance with the viscosity and fluidity of the fluid and the amount of one discharge. and a timer setting device 2 corresponding to the discharge amount per time determined by the mechanism structure such as the pitch and diameter of the screw 12 depending on the rotation speed.
Set 6.

In addition, if the fluid has high viscosity and poor fluidity and there is a risk that the fluid may not stably flow from the barrel 4 into the screw 12, in order to apply back pressure to the fluid in the barrel 4,
The pressure setting device 22 is set to a predetermined pressure value corresponding to the quality of the fluid and the discharge amount per hour.

After injecting a predetermined fluid into the barrel 4, the fluid dispensing device equipped with the screw-type discharge device according to the present invention is activated, and the screw and the air pump are driven for a predetermined short time, and the air inside is discharged to the second discharge port 6. The fluid is extruded from the air removal boat 14, and the screw 12 is filled with the fluid.

Once the above preparatory steps have been completed, the activation switch (not shown) of the entire dispensing system is pressed and the container to be dispensed with fluid is moved to a predetermined position below the second outlet 6 of the screw dispensing device. , a signal from the sensor 30 that detects the container is input to the control device main body 32.

Based on the input signal, the control device main body 32 controls the pressure setting device 2.
A signal specifying the pressure value set by 2 is output to the servo amplifier circuit 42, and the servo amplifier circuit 42 supplies a predetermined voltage to the motor 44 to drive the motor. motor 4
4 drives the air pump 46 and sends the generated pressurized air to the upper part of the fluid in the barrel 4 via the pipe 4a to apply pressure to the fluid. The pressure value is sensed by pressure sensor 48 and returned to servo amplifier circuit 42 . Therefore, a constant pressure set by the pressure setting device 22 is always supplied to the upper part of the fluid in the barrel 4.

In addition, the control device main body 32 is controlled by a signal from the sensor 30.
corresponds to the rotation speed value set by the 1 rotation speed setting device 24, and performs preset processing according to predetermined conditions such as a gear mechanism between the motor 8 and the screw 12,
Surho amplifies the signal indicating the rotation speed of the motor 8 that you created! Output to @34.

The servo amplifier circuit 34 corresponds to the input signal and supplies a predetermined voltage to the motor 8 to drive the motor.

The motor 8 drives the screw 12 and the air pump 46
is pushed from the outlet 16 of the barrel by the pressure of the pipe 1
8 is discharged from the second discharge port 6 into a predetermined container (not shown) in a constant amount determined by the structure of the screw and the set rotational speed.

The rotational speed of the motor 8 is detected by the tachometer 38 and sent back to the servo amplifier circuit 34. Therefore, the rotational speed of the motor 8 is always maintained at a predetermined rotational speed determined from the setting value of the rotational speed setting device 24. Therefore, screw 1
The rotation speed of No. 2 is maintained at the set value. In addition, as mentioned above, the fluid is pushed by a constant pressure from the top of the barrel and always flows uniformly into the screw, so the fluid flows into the second screw.
It is discharged from the discharge port 6 at a constant discharge amount.

In addition, the control device main body 32 is controlled by a signal from the sensor 30.
starts an internal timer, and when the value of the timer matches the value set by the timer setter 26, the control device main body 32 instructs the servo amplifier circuit 34 to change the direction of rotation of the motor 8. After outputting a signal with a predetermined voltage value indicating the opposite direction to the previous one for about 0-5 seconds, the output of the signal is stopped.

Therefore, the motor 8 is stopped instantaneously by the plugging operation. Therefore, the rotation of the screw 12 is stopped and the discharge of fluid is also stopped.

That is, a predetermined amount of fluid is correctly injected into the container.

Pressure is applied from the upper part of the fluid inside the barrel 4, but the increase in pressure due to the output side being stopped is detected by the pressure sensor 48.
The output value from the servo amplifier circuit 42 to the motor 44 decreases, and the rotation of the motor 44 is reduced. Therefore air pump 4
There is no risk that the rotation of the barrel 6 will decrease and the pressure from the upper part of the fluid in the barrel 4 will become excessive, causing the fluid to leak from the screw gap or the like.

When the value of the timer in the control device main body matches the value set by the timer setter 26 as described above and the rotation of the motor 8 stops, the control device main body 32 sends an output signal (not shown) to the next process. and move the filled container out and move the new empty container under the second outlet. When the movement is completed, the process returns to the beginning of this explanation and the next step begins.

In the above description, the time for applying the reverse voltage before stopping the motor 8 was described as approximately 0.5 seconds, but it is determined to be an appropriate time depending on the properties such as the viscosity of the fluid and the rotational speed of the motor. Alternatively, the time may be fixed, a reverse voltage may be applied, and the voltage may be turned off when the motor stops rotating.

In addition, the tachometer may be a generator-type one such as a tachometer, a means for counting the number of pulses output continuously in a unit time by a pulse encoder, etc., a proximity switch arranged at appropriate intervals, etc. The means for measuring the interval time between pulses output from the apparatus can be appropriately selected according to the specification conditions of the apparatus.

Next, another embodiment will be described with reference to FIG.

In No. 4121, 22 is the pressure setting device described above in FIG. The rotation speed setting device to be set is shown.

Further, 30 is a sensor that confirms the presence of a container to which a predetermined fluid is to be discharged and distributed from the discharge device and obtains a signal to start discharge.

Reference numeral 52 denotes a control device main body, which is composed of an electronic circuit having predetermined functions. 54 is an output circuit for driving the motor 8, which starts or stops the motor 8 in accordance with the signal level output from the control device main body 52 which converts each setting value mentioned above and outputs it as a rotational speed command value of the motor 8; It also controls the rotation speed.

The motor 8 is a DC motor, and is driven and controlled by an output circuit 54, and rotates the screw 12 at a predetermined speed for a predetermined time via a power transmission gear mechanism (not shown) to discharge a fixed amount of fluid. .

Reference numeral 58 denotes a rotation sensor for detecting the rotation of the screw, which is composed of a pulse encoder.
Determined by the function of the encoder.

It outputs a pulse corresponding to the rotation angle of the screw and No. 12 for each rotation of the screw. When the accuracy of the discharge amount is not required, the detected value of the rotation sensor 58 can be used as a signal indicating one revolution of the screwdriver, and the detected value is returned to the control device main body 52.
The control device main body 52 compares the set value set in the rotational speed setter 28 and outputs an output so that the deviation is zero, thereby controlling the rotation of the motor 8 and maintaining stable rotation of the screw 12.

Reference numeral 44 denotes a motor constituted by a DC motor, and includes an air pump 46 that generates pressurized air to apply a predetermined back pressure to the upper part of the fluid inside the barrel via the piping 4a, as described above in the explanation of FIG. , gear mechanism for power transmission (not shown)
Drive through.

42 is a servo amplifier circuit that drives the motor 44,
The motor drive power is output in accordance with a signal from the control device main body 52 which converts the pressure setting value set by the pressure setting device 22 and outputs it as an air pressure command value, starts or stops the motor 44, and also rotates the motor 44. Control speed.

A pressure sensor 48 detects the pressure obtained by the air pump 46, and the detected value of the pressure sensor 48 is returned to the servo amplifier circuit 42. Servo amplification port! @42 compares the detected value with a signal output from the control device main body 52, outputs the signal so that the deviation becomes zero, controls the rotation of the motor 44, and maintains the output air pressure of the air pump at the set value.

In the above block diagram, circuit elements that are not directly necessary for the explanation of the present invention are omitted, such as a power supply circuit, a power switch, a start/stop switch for the dispensing function, and a signal circuit that outputs a dispensing completion signal. There is.

Next, the operation in the above configuration will be explained.

When the fluid to be discharged and distributed by the screw type discharge device is determined, a rotation speed setting device 28 for determining the rotation speed of the screw 12 in accordance with the viscosity and fluidity of the fluid and the amount of discharge of - times; Depending on the rotation speed, screw 1
Discharge 1 determined by the mechanism structure such as pitch and diameter of 2
The screw 12 corresponds to the amount of fluid to be discharged per turn.
The rotation speed setting device 20 is set to set the number of rotations.

In addition, if the fluid has a high viscosity and poor fluidity and there is a risk that it will not flow stably from the barrel 4 to the screw 12, the pressure setting device 22 is used to apply back pressure to the fluid in the barrel. A predetermined pressure value is set depending on the quality and discharge amount per hour.

After injecting a predetermined fluid into the barrel 4, the fluid dispensing device equipped with the screw-type discharge device according to the present invention is started, and the screw and the air pump are driven for a predetermined short time, and the air inside is transferred to the second discharge port and air. The fluid is extruded from the drawing boat 14 and fills the screw.

When the above preparatory steps are completed, the activation switch (112 not shown) of all distribution systems is pressed, and the container to be discharged is moved to a predetermined position under the second discharge port 6 of the screw type discharge device. A signal from the sensor 30 that detects the container is input to the control device main body 52.

Based on the input signal, the control device main body 52 controls the pressure setting device 2.
A signal specifying the pressure value set by 2 is output to the servo amplification circuit 42, and the servo amplification circuit 42 is activated. @42 supplies a predetermined voltage to the motor 44 to drive the motor;
4 applies pressure from the upper part of the fluid in the barrel 4 with the pressurized air generated by driving the air pump 46 via the pipe 4a. The pressure value is detected by the pressure sensor 48 and returned to the servo amplification port &@42. Therefore, a constant pressure set by the pressure setting device 22 is always supplied to the upper part of the fluid in the barrel 4.

In addition, the control device main body 52 receives a signal from the sensor 30.
corresponds to the rotational speed value set by the rotational speed setting device 28, and generates a level signal that commands the rotational speed of the motor 8 by processing according to predetermined conditions such as the gear mechanism between the motor 8 and the screw 12. It is output to the output circuit 54. The output circuit 54 supplies a predetermined voltage to the motor 8 to drive the motor. The fluid that has been discharged is discharged from the second discharge port 6 into a predetermined container (not shown) at a constant rate determined by the structure of the screw and the set rotational speed.

The rotation of the screw 12 is detected by a signal sent back to the controller main body 52 from a rotation sensor 58 coupled to the screw 12. That is, the control device main body 52 compares the rotational speed of the screw 12 detected from the number of input pulse signals per time from the rotation sensor 58 constituted by a pulse encoder with the rotational speed setting device 28, and adjusts the rotational speed to a deviation or zero. The signal level output to the output circuit 54 is changed accordingly.

Therefore, the rotational speed of the motor 8 is always maintained constant.

So also. The rotational speed of the screw 12 is maintained at a constant value set by the rotational speed setting device 28. Also,
The control device main body 52 counts the number of pulse input signals from the rotation sensor 58, and when the number approaches a predetermined value with respect to the setting value of the rotation speed setting device 20 which determines the amount of discharge distributed per time, the control device main body 52 counts the number of pulse input signals from the rotation sensor 58. , the signal level output to the output circuit 54 is decreased, and when they match, the output of the signal is stopped, and the rotation of the screw is stopped.

Therefore, the rotation of the screw 12 is stopped and the discharge of fluid is stopped.

That is, a predetermined amount of fluid is precisely injected into the container.

Pressure is applied from the upper part of the fluid inside the barrel 4, but the increase in pressure due to the output side being stopped is detected by the pressure sensor 48.
The output value from the servo amplifier circuit 42 to the motor 44 decreases, and the rotation of the motor 44 is reduced. Therefore air pump 4
There is no risk that the rotation of the barrel 4 will decrease and the pressure from the upper part of the fluid in the barrel 4 will become excessive, causing the fluid to leak from the screw gap or the like.

When the motor stops rotating, the controller main body 52 sends an output signal (not shown) to the next process to move the filled container and move the new empty container under the second outlet. When the movement is completed, the process returns to the beginning of this explanation and the next step begins.

In the above explanation of FIG. 3, it was explained that the rotational speed of the motor is set and controlled, or it may be fixed depending on the usage conditions of the present dispensing device, or it may be set at a predetermined multiple level. You may select a fixed value for the motor, or you may select and specify an arbitrary value continuously.Also, although we explained that the plugging operation is performed when the motor stops, it is also possible to select a fixed value for the motor. Also good.

Further, in the explanation of FIG. 4, the motor is stopped by decelerating and stopping using a servo function, but the motor may be stopped by a plugging operation or by a normal stop.

Alternatively, the rotational speed of the screw may be set and controlled depending on the operating conditions of the single-screw discharge device, or the rotational speed may be adjusted to match the characteristics of the motor. There is no need to particularly control the rotational speed.

Although the rotation sensor 58 is described as using a pulse encoder, it is also possible to use any type of N4 type sensor according to the required accuracy, such as a proximity switch that operates with one revolution of the screw.

In the above explanation of Figs. 3 and 4, the screw drive motor was explained as a DC motor, but depending on the correspondence between the motor drive output circuit or servo amplifier circuit and the control device, it may be an AC motor or a pulse motor. Also, depending on the required precision of the discharge amount, it may be possible to simply control the motor on and off without providing a servo function.

Further, in the above description, the motor for driving the air bomber for controlling the back pressure of the liquid in the barrel was explained as a DC motor, but it may be an AC motor depending on the compatibility with the servo amplifier circuit or output circuit and control device for driving the motor. Also, depending on the required accuracy of pressure setting, it may be possible to simply control the motor on/off without providing a servo function.Also, it may be possible to control the air pump by simply controlling the motor, or by using a regulator installed in the pressure air circuit from a normal air pump. You may also do this.

In addition, it is also possible to change the air pressure on the surface of the liquid in the barrel, or by providing a 7-runner at the top of the la body, and adjusting and changing the pressure at the top of the plunger by an appropriate method using air pressure or a mechanical mechanism. Also. Depending on the characteristics of the fluid, such as its fluidity, it is not necessarily necessary to apply pressure to the surface of the liquid within the barrel.

Further, the servo amplification circuit may be configured by an electronic circuit, or the control device main body may be configured by a microcomputer and operated by software processing.

Further, although it has been described that the air naturally escapes from the air-bleeding boat 14, if necessary, the air may be forcibly vented using a vacuum pump or the like.

[Effects of the Invention] As explained in detail above, according to the present invention, when discharging fluid, the viscosity and fluidity of the fluid and the amount of fluid in the barrel can be controlled by precisely controlling the rotational speed of the screw and the stop timing. In addition, since the screw is used for pressure feeding, the influence of bubbles can be removed, and even during continuous discharge, the amount of fluid discharged can be stabilized, and a fixed amount can be discharged. be able to.

[Brief explanation of drawings]

Figure 1 shows an overview of the screw type discharge device based on the present invention.
Figure 2 is a side view of the configuration of the barrel and motor section in the screw type discharge device shown in Figure 1, and Figure 3 is an overview of the control circuit in the general configuration example of the screw type discharge device shown in Figure 1. Block Diagram FIG. 4 is a schematic block diagram of a circuit using another control method. In the figure, 2 is a control device, 4 is a barrel, 6 is a second discharge port, 8 is a motor, 10 is a mechanism, 12 is a screw,
14 is a boat, 16 is a barrel discharge port, 18 is a pipe, 2
0 is a rotation speed setting device, 22 is a pressure setting device, 24 is a rotation speed setting device, 26 is a timer setting device, 28 is a rotation speed setting device, 30 is a sensor, 32 is a control device main body, 34 is a servo amplifier circuit, 38 is a tachometer, 42 is a servo amplifier circuit, 4
4 is a motor, 46 is an air pump, 48 is a pressure sensor, 5
2 is a control device main body, 54 is an output circuit, and 58 is a rotation sensor. Applicant Iwashita Engineering Co., Ltd. Agent
Patent Attorney Yoshimi SaigoFigure 2Figure 1Figure 3Figure 3

Claims (1)

[Claims] 1. A fluid container equipped with a discharge port, a screw that extracts fluid in the container from the discharge port and moves it to a second discharge port, a screw drive mechanism, and a control device that controls the rotation of the screw drive mechanism. A screw-type discharge device characterized by comprising: