JPH02191104A - Apparatus for charging by weight - Google Patents

Abstract

PURPOSE:To always maintain relation between a charging nozzle and a liquid level constant by a method wherein time elapsed since opening of a liquid valve until reference weight can be obtained is detected, and rising rate of the charge nozzle is compensated according to the elapsed time. CONSTITUTION:A controller 9 is provided with a driver 50 for lifting a charge nozzle 16 by controlling rotation of a servo motor 49 in forward and reverse directions and a valve open/close controller 51 for controlling opening/closing of a liquid valve 25 while a cross reference table indicating relation between time from opening of the liquid valve 25 and height position of the charge nozzle 16 is stored in the driver 50 as per type of vessels. In addition, the controller 9 is provided with a measuring section 52 for detecting the elapsed time until the charged weight reaches reference weight and a compensating section 53 for compensating the cross reference table stored in the driver 50 according to the elapsed time, wherein the compensating section 53 compensates the correspondence in the cross reference table to make rising rate of the charge nozzle increase as the elapsed time becomes shorter and make it decrease as the elapsed time becomes longer.

Description

Detailed Description of the Invention "Field of Industrial Application" The present invention relates to a gravimetric filling device for filling a predetermined weight of a filling liquid into a container, and more specifically, a filling nozzle for filling a filling liquid into a container. The present invention relates to a gravimetric filling device that raises the liquid level in a container in accordance with the rise in the liquid level.

"Prior Art" Conventionally, a weight filling device is known that includes a weighing scale for measuring the weight of a container, a filling nozzle for filling the container with a filling liquid, and a lifting mechanism for lifting and lowering the filling nozzle (for example, Utility Model Publication No. 52-35229).

In this gravimetric filling device, the lower end of the filling nozzle is immersed in the filling liquid, and a liquid level sensor installed at the lower end moves the filling nozzle upward by following the rising level of the filling liquid. When the liquid level reaches a predetermined height, the lower end of the filling nozzle is pulled up from the filling liquid, and when the weighing scale detects that the filling weight has reached a predetermined weight, the liquid valve is closed to complete filling.

In addition, in order to raise the filling nozzle to follow the rise in the level of the filling liquid, the relationship between the filling weight and the height position of the filling nozzle is measured in advance, and the driving source for the lifting mechanism is a servo motor. There has also been proposed a device in which the filling mold M is measured by the weight scale and the position of the filling nozzle is controlled by a servo motor to a height position corresponding to the filling weight (Japanese Patent Application No. 62-201630).

``Problem to be Solved by the Invention'' However, in the former gravimetric filling device, if the filling liquid foams for some reason at the beginning of filling, it becomes difficult to accurately set the liquid level using the liquid level sensor. There are drawbacks.

On the other hand, in the latter gravimetric filling device, the position of the filling nozzle can be controlled at a height corresponding to the filling weight of the filling liquid in the container, so it has the advantage that it is not affected by foaming of the filling liquid. be.

However, on the other hand, the inertia force of the filling liquid filled into each container from the filling nozzle is added to the filling weight measured by the weighing scale. If this inertial force is stable, it is possible to control the height position of the filling nozzle by taking it into account. At the start, the inertial force fluctuates greatly, making it difficult to control the height position of the filling nozzle.

To solve this problem, after the start of filling, the filling nozzle is raised at a predetermined rate of rise, regardless of the actual filling weight, until the inertia force stabilizes. Once the time has elapsed, the height position control of the filling nozzle can be performed based on the filling weight.

However, if the filling nozzle is raised at a predetermined rate of rise regardless of the filling weight, if the viscosity of the filling liquid changes or the pressure applied during pressurized filling changes, etc. Since the actual rate of increase in the liquid level varies, the predetermined rate of increase in the filling nozzle does not match the actual rate of increase in the liquid level.

"Means for Solving Section!!" In view of such circumstances, the present invention provides a weighing scale for measuring the weight of a container, a filling nozzle for filling a filling liquid into the container, and a method for raising and lowering the filling nozzle. In the weight filling device equipped with a lifting mechanism, the driving source of the lifting mechanism is a servo motor, and a control device is provided that inputs a signal from the weighing scale and controls the servo motor to lift and lower the filling nozzle. and the control device includes a drive unit that raises the filling nozzle at a predetermined rate of increase regardless of the filling weight until the filling mold in the container reaches a predetermined reference weight; a valve opening/closing control unit that closes the liquid valve of the filling nozzle when it detects that the desired predetermined weight has been reached; a measuring unit that detects the elapsed time from when the liquid valve is opened until the reference weight is obtained; The present invention provides a weight filling bag W characterized by comprising a correction section that corrects the rate of rise of the filling nozzle to decrease or increase in accordance with an increase or decrease in elapsed time.

In addition, the M2 invention has a different configuration of the control device, and the control device in the second invention has no relation to the filling weight until a predetermined reference time has elapsed after opening the liquid valve of the filling nozzle. a drive unit that raises the filling nozzle at a predetermined rate of increase; a valve opening/closing control unit that closes the liquid valve when it detects that the filling weight reaches the predetermined weight; and a filling weight when the reference time has elapsed. The present invention is characterized by comprising a correction unit that corrects the rate of rise of the filling nozzle to increase or decrease in accordance with an increase or decrease in the filling nozzle.

"Function" According to the above configuration, from the time the liquid valve is opened until the filling weight in the container reaches the predetermined reference voltage, or until the predetermined reference time elapses, filling is performed regardless of the filling amount 1. Since the nozzle is raised at a predetermined rate of rise, the filling nozzle is not affected even if the filling liquid foams or the detected weight fluctuates greatly due to filling with a large flow of filling liquid. It can follow the rise in liquid level.

If the viscosity of the filling liquid fluctuates or the pressurizing force during pressurized filling fluctuates, the amount of filling per unit time fluctuates, and as a result, the rate of rise of the liquid level in the container fluctuates. , in the first invention, detecting the elapsed time from when the liquid valve is opened until the reference weight is obtained;
For example, if the elapsed time becomes shorter, that is, if the amount of filling per unit time increases and the rate of rise of the liquid level in the container increases, the rate of rise of the filling nozzle is increased in accordance with the amount of increase. Since the correction has been made in this manner, the relationship between the filling nozzle and the liquid level can always be maintained constant.

On the other hand, in the second invention, the filling amount t when a predetermined reference time has elapsed after opening the liquid valve of the filling nozzle.
For example, when the filling weight increases, that is, when the filling liter per unit time increases and the rate of rise of the liquid level in the container increases, the filling nozzle Since the correction is made so as to increase the rate of increase of , the relationship between the filling nozzle and the liquid level can always be maintained constant.

``Example'' Hereinafter, an example in which the present invention is applied to a rotary gravimetric filling product will be described. In FIG. The container 2 carried into the interior by the wheel 4 and filled with a predetermined weight of filling liquid by the rotary heavy filling device 3 is discharged onto the conveyor 1 by the discharge star wheel 5.

As shown in FIG. 1, the rotary weight filling machine 3 is equipped with a cylindrical rotating body 6 that is attached to a vertical main shaft (not shown) and rotated in one direction.
A flange portion 6 protruding radially outward at the outer periphery of the
A is provided with a meter 7 for measuring the weight of the container 2 at equal intervals in the circumferential direction. A support table 8 for 2% RM of the container is attached to the top of each weight scale 7, and signals from the total 7 are inputted to a control unit 9 having a microcoscipulator.

Filling nozzles 168 for filling the container 2 placed on the supporting table 8 with the filling liquid are disposed in the upper part of each supporting table 8 in the rotating body 6, and each filling nozzle 16 can be raised and lowered by a lifting mechanism 17 provided on the rotating body 6.

As shown in FIG. 2, the valve housing 18 of each filling nozzle 16 is attached to the upper end of a lifting member 19 constituting the lifting mechanism 17, and the valve housing 18 has a filling passage 20 below its axis. ¥! is forming. The upper end of this filling passage 20 is communicated with a filling liquid tank (not shown) via a radial hole 21 bored in the valve housing 18 and a visible conduit 22 connected thereto, and the lower end thereof is connected to a filling liquid tank (not shown) in the valve housing 18. It communicates with the liquid injection pipe 23 attached to.

A liquid valve 25 made of a bottomed cylindrical bellows is housed in the valve housing 18.
is connected to the piston rod 27 of the cylinder device 26, and when the piston rod 27 is lowered, the valve seat portion 1 in which the valve portion 25a at the bottom of the valve is formed in the valve housing 18.
8a so that the filling passage 20 can be closed.

The piston 28 of the cylinder device 26 formed at the upper end of the piston rod 27 has a first pressure chamber 29 in its upper part and a second pressure chamber 30 in its lower part, and an M1 supply passage formed in the valve housing 18. 31 to the above 1st
When compressed air is supplied to the pressure chamber 29, the piston 28 and piston rod 27 are lowered to close the valve portion 2.
5a is seated on the valve seat portion 188, thereby allowing the above-mentioned filling passage 20 to be closed.

On the other hand, when compressed air is supplied to the second pressure generator 30 from the second supply passage 32 formed in the valve housing 18, the piston 28 and the piston rod 27 are raised to move the valve portion 25a toward the valve seat. 18a, thereby opening the filling passage 20.

Also, inside the valve housing 18, the piston 2
A second piston 33 is fitted in a position below 8 so as to be able to rise and fall freely, and the piston rod 27 is slidably penetrated through the details of the second piston 33. This second piston 33
is formed to have a larger diameter than the piston 28, the above-mentioned second pressure chamber 30 is formed in the upper part, and the third pressure chamber 30 is formed in the lower part.
A pressure chamber 34 is formed.

Therefore, when compressed air is supplied into the second pressure chamber 30 of the cylinder device 26, the second piston 33 is positioned at the lower end to allow the piston 28 to rise, and in this state, the filling passage 20 is fully opened. Therefore, the filling liquid can be filled into the container 2 at a large flow rate.

On the other hand, the third valve formed in the valve housing 18
Compressed air is supplied to the third pressure chamber 34 via the supply passage 35 to position the second piston 33 at the rising end, and at the same time, compressed air is supplied to the first pressure chamber 29 to position the piston 2.
When the piston 8 is lowered, the piston 28 comes into contact with the second piston 33, and its free descent to the lowering end is restricted. In this case, the liquid valve 25 is opened to a small degree, and the filling liquid is filled into the container 2 in a small flow 1.

Generally speaking, in addition to the supply passages 31, 32, and 35, the valve housing 18 has an atmospheric pressure chamber 36 formed in the liquid valve 25 that is connected to the atmosphere in order to allow the volume of the atmospheric pressure chamber 36 to vary. An atmospheric passage 37 is formed to open to the atmosphere, and each of these passages 31, 32, 35, 37 communicates with each of passages 38 to 41 provided inside the elevating member 19.

Passages 38 to 41 provided inside the elevating member 19
Among them, the passage 41 communicating with the atmospheric pressure chamber 36 is opened to the atmosphere at the lower end of the elevating member 19, but the other passages 38 to 40 are provided with flexible conduits and electromagnetic valves (not shown), respectively. It is connected to a compressed air source via.

Next, as shown in FIG.
Supporting vibrators 46 and 46' provided at b and 6c are penetrated through the support vibrators 46 and 46', respectively, so as to be non-rotatable and movable up and down.

The upper and lower discs 6b, 6 are parallel to this elevating member 19.
A screw shaft 47 is rotatably supported on 0M, and the screw shaft 47
A nut member 48 fixed to the elevating member 19 is screwed together.

A servo motor 49 is connected to the lower end of the screw shaft 47 and is fixed to the bottom surface of the disc 6c and whose rotation is controlled by the control table M9.By rotating the servo motor 49 in forward and reverse directions, the The filling nozzle 16 can be raised and lowered via a lifting member 19.

The control device 9 includes a drive section 50 that controls the rotation of the servo motor 49 in forward and reverse directions to raise and lower the filling nozzle 16, and a valve opening/closing control section 51 that controls opening and closing of the filling nozzle and the liquid valves 25 of 16. The drive unit 50 includes a filling nozzle that is set in advance for each type of container, taking into consideration the time since the liquid valve 25 is opened and the height of the liquid level in the container that increases with the passage of time. A correspondence table showing the relationship with the height position of 16 is stored.

The control device 9 also detects the elapsed time from when the liquid valve 25 is opened until the actual filling weight reaches a predetermined standard critical condition, for example, 90% of the predetermined weight to be filled. A measuring section 52 and a correcting section 5 that corrects the correspondence table stored in the driving section 50 according to the elapsed time.
3, the correction unit 53 increases the rate of rise of the filling nozzle as the elapsed time becomes shorter, and decreases the rate of rise of the filling nozzle as the elapsed time becomes longer; The correspondence relationships in the above correspondence table are corrected.

In the above configuration, when the filling nozzle 16 is located at the rising end position and the liquid valve 25 is closed, the air is discharged from the supply star wheel 4, which rotates in synchronization with the rotation of the rotary body 6, onto the support table 8. When containers 2 of
The weight 1 of the empty container 2 is stored in response to a signal input from the container 2. As a result, zero adjustment is performed by subtracting the weight of the empty container 2 from the detected weight, as indicated by the symbol X in FIG.

At the same time, in the movement section A, the drive unit 50 of the control table M9 lowers the filling nozzle 16 that was located at the rising end, and moves the lower end of the liquid injection pipe 23 to the lowering end position close to the bottom of the container 2. This operation is performed based on a signal from a detector (not shown) that detects the rotational position 11 of the rotating body 60 times. At this time, 5. To prevent the lower end of the liquid injection pipe 23 from coming into contact with the bottom of the customer device 2 and damaging the container 2, the lower end of the liquid injection pipe 23 should be set so as to be separated from the bottom of the container 2 by the required distance. Of course there is.

When the filling nozzle 16 moves to the moving section B after being located at the lowering end position in the movement diagram 1ttlA, the valve opening/closing control section 51 of the control device 9 opens the above-mentioned solenoid valve to set the second pressure. Compressed air is supplied into N30 to fully open the liquid valve 25. As a result, the filling liquid is transferred from the filling liquid tank (not shown) to the conduit 22, the radial hole 21,
The container 2 is filled at a large flow rate through the filling passage 20 and the liquid injection pipe 23.

The type of container 2 to be used is input into the control device 9 in advance before starting the filling operation, and the drive unit 50 of the control device 9 selects a necessary correspondence table according to the type of container 2. ing. When the valve opening/closing control section 51 opens the liquid valve 25, the driving section 50 raises the filling nozzle 16 at a required rate of increase set in the correspondence table as time passes.

Therefore, even if the weight detected by the weighing scale 7 changes greatly due to fluctuations in the inertia of the filling liquid filled into the container 2 from the filling nozzle 16 immediately after the liquid valve 25 is opened at point Y in FIG. The filling nozzle 16 can be raised smoothly (see Figures 4b and 4c).

By opening the liquid valve 25, filling of the filling liquid progresses, and the M
5, when the filling weight reaches the reference weight which is smaller than the predetermined weight to be filled, the valve opening/closing control unit 5
1 switches the solenoid valve to provide the first pressure chamber 29 and the third pressure chamber 34.
(At the same time, compressed air is supplied and the opening degree of the liquid valve 258 is switched to a small degree. Therefore, the filling liquid is filled from the filling nozzle 16 into the container 2 at a small flow rate.
Travel section C) in Figure 3.

Even when the liquid valve 25 is switched to a small opening degree, the filling nozzle 16 continues to be gradually raised based on the above correspondence table,
Eventually, when the filling weight reaches a predetermined weight to be filled, the drive unit 50 supplies compressed air only at the first pressure N 29 to close the liquid valve 25 and finish filling the container 2 with the filling liquid.

When this state is reached, the control device 9 raises the filling nozzle 16 to the upper end position and pulls out the liquid injection pipe 23 from the container 2, and the filled container 2 is transported by the discharge star wheel 5 through the support table 8. 1 and the filling operation is completed (see moving section D in Figure M3 and Figure 4d).

By the way, the measurement section 52 measures the elapsed time from when the liquid valve 25 is opened until the filling weight reaches the reference weight, and the correction section 53 measures the elapsed time in the drive section 50 according to the elapsed time. Correct the correspondence table.

Here, an example of the correction by the correction section 53 will be specifically explained. For example, the reference time of the elapsed time is 3000 ms.
(3 seconds), and the tolerance is ±100m5, the correction unit 53 measures the elapsed time in 1/1000 second vehicle position, and calculates the average value of the latest 5 filling operations. .

For example, the first 5 measurement times are 2980m5.300
0ms, 2900m5.2920m5.2950m5, the average time is 2950m5, so this is within the above tolerance ± of the reference time of 3000ms.
Since it is within the range of rooms, the correction unit 53 does not perform correction.

When the 6th elapsed time is measured, the average value of the latest 5 filling operations from the 2nd to the 6th filling operation is calculated, and the average value is within the allowable error range with respect to the reference time. A determination is made as to whether or not it is within the range.

Here, the latest 5 measurement times are 2950m5.283
0m5.2900m5.2820m5.2800m5, their average time is 2860m
5, and therefore exceeds the above tolerance. In other words, in this case, for example, the viscosity of the filling liquid has decreased and the above-mentioned reference weight has been achieved in a shorter time than the reference time. This means that the liquid level has risen, and therefore, in order to maintain the optimum distance between the two, it is necessary to increase the rate of rise of the filling nozzle 16 compared to the current level.

Therefore, the correction unit 53 changes the reference time in the correspondence table for the drive unit 50 from the previous 3000ms to 2860m5, which exceeds the above tolerance, thereby changing the previous 3000ms in the drive unit 50 to the reference time. The correspondence table will be changed from the above correspondence table to the correspondence table in which the reference time is 2860m5.

As a result, when the viscosity of the filling liquid becomes smaller and the level of the filling liquid rises at a faster rate than the rise of the filling nozzle 16 up to that point, the rising of the filling nozzle 16 increases. Therefore, the gap between the filling nozzle 16 and the liquid level becomes too narrow, or the lower end of the filling nozzle 16 is immersed in the filling liquid. Such things can be prevented.

After this, it is determined whether the latest five measurement times are within the tolerance range of ±100 m5 with respect to the new reference time of 2880 m5.

Next, in the above embodiment, correction is made by measuring the elapsed time until the filling weight reaches the reference weight, but in contrast to this, the measuring section 52
The filling mold t may be measured when a predetermined reference time elapses after the liquid valve 25 of No. 6 is opened, for example, in the case of the above embodiment, a sufficiently short reference time of about 2500 m5.

In this case, if the actual filling weight is larger than the standard filling weight when the reference time has elapsed, the liquid level rises faster, so the correction unit 53 controls the filling nozzle 16. It is clear that the correction should be made to increase the rate of increase in .

If necessary, a weight correspondence table showing the filling weight of the filling liquid filled into the container and the height position and distance of the filling nozzle 16 at the time of the filling weight is also stored, and the weight correspondence table is stored and compared to the above-mentioned reference weight. After the actual filling mold jl is measured, or after the reference time has elapsed, the filling nozzle 16 may be raised to follow the actual filling mold jl.

However, in the first embodiment, it is not necessary to set the reference mold j1 to be smaller than the predetermined weight to be filled, and it goes without saying that the reference weight ta may be made equal to the predetermined weight to be filled.

Further, in the above embodiment, the lower end of the filling nozzle 16 is maintained at a position above and close to the liquid level in the container 2 and raised, but if necessary, the lower end of the filling nozzle 16 may be lowered into the filling liquid. It may be made to rise as the liquid level rises in the inserted state.

Furthermore, in controlling the rising height 1t of the filling nozzle 16, it is not necessarily necessary to use the above-mentioned correspondence table; once the filling weight is input, the filling nozzle 16 is
Of course, the height position of the object may also be determined.

In the above embodiments, the present invention is described in detail in a rotary gravimetric filling system [
(As I explained next, when this is applied, the line type heavy I
Of course, it may also be a filling device.

"Effects of the Invention" As described above, according to the present invention, even if the detected weight changes significantly due to foaming of the filling liquid or filling with a large flow rate of the filling liquid, it will not be affected by this. The filling nozzle can be made to follow the rise in the liquid level without any problems, and it can also be used when the viscosity of the filling liquid or the pressurizing force during pressurized filling increases, for example, when the rate of rise in the liquid level in the container increases. can be corrected so as to increase the rate of rise of the filling nozzle according to the amount of increase, so the effect can be obtained that the relationship between the filling nozzle and the liquid level can always be managed with high precision.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing one embodiment of the present invention, and FIG.
Figure 3 is an enlarged sectional view of the main parts of the figure, Figure 3 is a schematic plan view of the whole, Figures 4a to 4d are operation process diagrams showing the filling state, Figure 5 is the relationship between filling weight and time after the start of filling. FIG. 2...-Container 6... Rotating body 9... Control device + 7-... Lifting mechanism 50-... Drive section 52-... Measuring section 3... Rotary mortuary filling device 7... Weight Total + 6 - Filling nozzle 49 - Servo motor 51 - Valve opening/closing control section 53 - Correction section

Claims (2)

[Claims] (1) In a weight filling device equipped with a scale for measuring the weight of a container, a filling nozzle for filling the container with filling liquid, and an elevating mechanism for elevating and lowering the filling nozzle, the drive source of the elevating mechanism is controlled by a servo. A motor is provided, and a control device is provided which inputs a signal from the weight scale and controls the servo motor to raise and lower the filling nozzle, and the control device operates until the filling weight in the container reaches a predetermined reference weight. includes a drive unit that raises the filling nozzle at a predetermined rate of increase regardless of the filling weight, and a valve opening/closing control unit that closes the liquid valve of the filling nozzle when it detects that the filling weight has reached the predetermined weight to be filled. , a measurement unit that detects the elapsed time from when the liquid valve is opened until the reference weight is obtained; and a correction unit that reduces or increases the rate of rise of the filling nozzle in accordance with an increase or decrease in the elapsed time. A weight filling device characterized by comprising a correction section that (2) In a weight filling device equipped with a scale for measuring the weight of a container, a filling nozzle for filling the container with filling liquid, and an elevating mechanism for elevating and lowering the filling nozzle, the drive source of the elevating mechanism is controlled by a servo. A control device is provided which inputs a signal from the weighing scale and controls the servo motor to raise and lower the filling nozzle. A drive unit that raises the filling nozzle at a predetermined rate of increase regardless of the filling weight until a reference time has elapsed, and a valve opening/closing control unit that closes the liquid valve when it is detected that the filling weight has reached the predetermined weight. and a correction unit that corrects the rate of rise of the filling nozzle to increase or decrease in accordance with the increase or decrease in the filling weight when the reference time has elapsed.