JPH11152102A - Powder filling apparatus and method - Google Patents

Abstract

(57) [Abstract] (with correction) [Problem] To suppress the variation in the weight of cut powder, suppress the decrease in weighing accuracy due to long-term use, and suppress the decrease in weighing accuracy when the specific gravity of powder changes. In addition, variations in the weighing time are suppressed. SOLUTION: This powder filling apparatus cuts a certain amount of powder and sequentially fills the container, and a shutter 1a provided at a lower end of the powder storage means 1 and a servo for adjusting an opening width of the shutter 1a. Motor 6 and load cell 3 for measuring the weight of the powder dropped by the opening of shutter 1a
When the separation of the powder is started, the servo motor 6 is controlled based on the weighed weight of the load cell 3 so that the opening width of the shutter 1a gradually decreases from the large opening width to the small opening width with the passage of time. And a control device for cutting the powder having the target weight and filling the container with the target weight. The control device performs the following measurement so that the weighing time from the start of the powder cutting to the end of the cutting is constant. Is corrected for the large opening width.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a powder filling apparatus and a powder filling method, and more particularly to a technique for filling powder with no variation in target weight.

[0002]

2. Description of the Related Art When a powder is cut into a uniform weight and filled into a container or the like, a shutter provided at a lower end of a hopper in which the powder is stored is conventionally opened and closed using mechanical means including a cam and a rod. The falling of the powder was adjusted and the weight of the dropped powder was measured using a balance. When the measured value reached a predetermined value, the shutter was closed.
If the cut weight deviates from the specified weight range when the powder is cut several times, the weight of the weight, which is the basis of the weight measurement on the balance, is adjusted to keep the powder constant. Was to be carved by weight.

[0003]

However, in the above-mentioned conventional powder filling apparatus, the variation in the powder filling weight was large due to the following matters. That is, the shutter is opened and closed by the cam being actuated and pressed by the rod, and the movement of the shutter becomes poor due to the adhesion of powder, so that the measurement accuracy is reduced. Prolonged use wears the edges of the support that supports the balance rod, reducing weighing accuracy. After the powder was cut several times, the weight of the weight was adjusted when the weight of the cut powder deviated from the specified weight range.If the specific gravity of the powder changed, adjust the weight of the weight. During this time, the weight may deviate significantly from the specified weight or the weighing time may vary.

[0004] The present invention has been made in view of the above-mentioned problems, and has the following objects. (1) To provide a powder filling apparatus and method capable of suppressing variation in weight of cut powder. (2) To provide a powder filling device capable of suppressing a decrease in measurement accuracy due to long-term use. (3) To provide a powder filling apparatus and method capable of suppressing a decrease in measurement accuracy when the specific gravity of the powder changes. (4) To provide a powder filling apparatus and method capable of suppressing variations in measuring time.

[0005]

In order to achieve the above object, the present invention relates to a powder filling apparatus which cuts a fixed amount of powder and sequentially fills a container with the powder. A shutter provided at the lower end of the body housing means, a servomotor for adjusting the opening width of the shutter,
A load cell for measuring the weight of the powder dropped by the opening of the shutter, and when the separation of the powder is started, the opening width of the shutter is changed from the large opening width to the small opening width with the passage of time based on the measured weight of the load cell. And a control device for controlling the servomotor so as to gradually narrow the powder to separate the target weight of powder and filling the container. The control device has a constant weighing time from the start of powder separation to the end of separation. In order to achieve the above, means for correcting the large opening width at the time of separating the next powder is adopted.
Further, such a means is provided with a weight checker for measuring the filling weight of the container filled with the powder, and the control device is configured to set the target weight of the powder cutout based on the filling weight measured by the weight checker. It is conceivable to add a means for correcting the small opening width of the shutter at the time of separating the next powder so that

[0006] As means relating to the powder filling method,
A powder filling method in which a certain amount of powder is cut out and sequentially filled in a container, and the opening width of a shutter is gradually reduced from a large opening width to a small opening width by using a servo motor for the stored powder. When the powder having the target weight is cut in such a manner, means for correcting the large opening width and performing the next cutting is adopted so that the weighing time becomes constant. It is also conceivable to add a means for correcting the small opening width and performing the next cutting so that the measured weight of the actually cut powder becomes the target weight.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS.
The powder filling device and method according to the present invention will be described. In the present embodiment, the present invention is applied to filling of a powder cleaning agent.

First, the configuration of the powder filling apparatus according to the present embodiment will be described with reference to FIG. In this figure, reference numeral 1 denotes a powder storage hopper (powder storage means), in which a powder detergent A (powder) is stored, and a shutter 1a is provided at a lower end thereof. Shutter 1a
Is configured to be opened and closed by rotating in the direction of arrow X about the fulcrum 1a, and by rotating, a part of the powder detergent A is dropped onto the weighing hopper 2 arranged below. It is configured as follows.

FIG. 2 is a perspective view showing the detailed structure of the shutter 1a. As shown in FIG.
a is formed by joining the respective peripheral portions of two arc plates 1c and 1d parallel to each other with a curved plate 1e. The powder storage hopper 1 is provided with a rectangular plate material 1f protruding downward, and the shutter 1a is rotatably attached to the powder storage hopper 1 via a fulcrum 1b. , The powder detergent A is dropped from a gap formed between the plate material 1c. Further, a groove 1g is provided on the plate member 1f side of the curved plate 1e, so that the area of the gap can be finely adjusted according to the rotation of the shutter 1a.

The weighing hopper 2 is supported by a device main body (not shown) via a load cell 3.
An opening / closing door 2a is provided at the lower end. Load cell 3
Measures the weight of the weighing hopper 2. A tare 4 (container) placed on a transfer means (not shown) is arranged below the door 2a, and the tare 4 is transferred onto the weight checker 5 by the transfer means. It has become. Weight checker 5
Is for weighing the weight of the tare 4 filled with the powder detergent A.

An axis of a servo motor 6 is connected to a fulcrum 1b of the shutter 1a, and an encoder 7 for detecting the rotation is mounted on the axis of the servo motor 6. The servo motor 6 is driven by a servo motor controller 8, and the servo motor
The controller 8 is controlled by a servo motor / amplifier 9.

The servo motor / amplifier 9 is provided with a weight value of the weighing hopper 2 inputted from the load cell 3 and a servo motor 6 fed back from the encoder 7.
A control signal for instructing the amount of rotation of the servo motor 6 is generated based on the detected rotation amount of the servo motor 6 and output to the servo motor controller 8. The opening / closing door 2a is a cylinder 1
0, the cylinder 1
0 is controlled by the filling machine sequencer 11.

The filling machine sequencer 11 controls the entire operation of the present powder cutting device, and includes a servomotor
The cylinder 10 is controlled based on the weight of the weighing hopper 2 input from the load cell 3 via the amplifier 9. That is, the filling machine sequencer 11 controls the cylinder 10 so that the opening / closing door 2a is opened when the powder detergent A is dropped into the weighing hopper 2 and its weight is stabilized.

The filling machine sequencer 11 has a target weight, a permissible weight range, a weighing time (to be described later) and a permissible weighing of the separated powder detergent B to be cut from the hopper 1 for storing powder to the hopper 2 for weighing. The time range is stored in the internal memory in advance. The filling machine sequencer 11
The data stored in the internal memory and the weight measured by the weight checker 5, that is, the filling weight of the cut powder detergent B actually filled in the tare 4, and the time actually measured by various internal timers The operation of the servo motor 6, that is, the opening and closing of the shutter 1a, is controlled based on the weighing time. The servo motor controller 8, the servo motor amplifier 9, and the filling machine sequencer 11 constitute a control device.

Next, the filling machine sequencer 11 shown in FIG.
A method for filling powder using the above-described powder filling apparatus will be described with reference to the operation flow of FIG. In the present embodiment, as described below, the opening width of the shutter 1a is set to a large opening width (large opening width) and a small opening width (small opening width), that is, set in two stages. The large powder opening width, the small powder opening width, and the shutter 1
It is also assumed that the time when a is set to the large input opening width (large input opening time) and the time when the small input opening width is set (small input opening time) are also stored in the internal memory of the filling machine sequencer 11 in advance.

First, when the transfer means places the tare 4 below the door 2a, this is detected by a sensor (not shown), and a tare pull-in signal a (see FIG. 4) is input to the filling machine sequencer 11. You. The filling machine sequencer 11 starts the input timer of the tare pull-in signal when the tare pull-in signal a is input (Step S1), and outputs the weighing start signal b to the servo motor amplifier 9 when the input timer counts up. (Step S2).

The filling machine sequencer 11 starts a timer for measuring the large opening time (output timer of a large opening width) at the same time as the output of the weighing start signal b (step S3). A timer for measuring the opening time (output timer for the small opening width) is started (step S4). On the other hand, as shown in FIG. 4, the servo motor amplifier 9 outputs the large closing control signal c to the servo motor controller 8 until the output timer of the large closing opening time expires, and the small closing opening signal. Until the output timer for the width times out, the small input control signal d is output to the servo motor controller 8.

The large closing control signal c is a control signal for instructing opening of the shutter 1a with a large opening width, and the small closing control signal d is a control for instructing opening of the shutter 1a with a small opening width. Signal. In this case, the small input control signal d is input to the servomotor controller 8 for a period longer than the large input control signal c by a certain time.

In a state where the two control signals are simultaneously inputted, the servo motor controller 8 drives the servo motor 6 to open the shutter 1a with a large opening width in accordance with the large closing control signal c.
In this case, the large input opening width may be set to a constant opening width or to gradually narrow the opening width with the passage of time.

When the large closing control signal c is stopped, the servo motor 6 is driven so as to open the shutter 1a with a small closing opening width in accordance with the small closing control signal d. As a result, during the period (large throw time shown) in which the large throw control signal c and the small throw control signal d are simultaneously input to the servomotor controller 8, the shutter 1a is opened with the large throw opening width. Load cell 3
Powder detergent B divided from the powder storage hopper 1 to the measurement hopper 2 of the weight measured by
Increases relatively sharply as shown by characteristic e.

Subsequently, during a period in which only the small throw control signal d is input to the servomotor controller 8 (small throw time shown), the shutter 1a is opened with a small throw opening width, so that the cut powder washing is performed. The weight of agent B will increase relatively slowly over time, as shown by characteristic f. When the output of the large injection control signal c and the output of the small injection control signal d are stopped, the servo motor
The controller 8 drives the servo motor 6 so that the shutter 1a is closed.

As shown in FIG. 4, during the period in which the shutter 1a is closed (fall time), the separated powder detergent B
Changes more slowly than the characteristic f, as indicated by the characteristic g, and becomes to be indicated by the characteristic h after the elapse of the head time. When the shutter 1a is completely closed and the falling time ends, the change in weight of the cut powder detergent B becomes constant as shown by the characteristic h. The weight at this time is the cut weight of the cut powder detergent B finally cut into the weighing hopper 2.

The output timer for the small opening width is timed up (that is, the output of the small insertion control signal d is stopped).
Then, the filling machine sequencer 11 starts a weighing completion output timer to measure a certain time (step S5),
When the weighing completion output timer times out, a weighing completion signal j is output to the servo motor amplifier 9 (step S6). The metering completion output timer starts measuring time from the stop time of the small injection control signal d,
When the weight change becomes stable to a constant value and a certain period elapses, the time is up and a weighing completion signal j is output.

That is, as shown in FIG. 4, the filling machine sequencer 11 sets the time (weighing time) from the output of the weighing start signal b to the output of the weighing completion signal j to be a predetermined fixed time. The large opening width of the shutter 1a and the servo motor 6 when the large closing control signal c is output.
Is set.

Here, the rate of change in weight of the powder cleaning agent A falling into the weighing hopper 2 with respect to the fixed opening width of the shutter 1a differs when the specific gravity of the powder cleaning agent A, that is, the material changes. . Therefore, when the large input opening width and the small input opening width are constant, in order to separate the target weight of the separated powder cleaning agent B, the above measuring time is set to the powder cleaning agent A.
Needs to be changed according to the type (material) of the device.

Under such circumstances, the filling machine sequencer 11 changes the large charging opening width according to the type of the powder detergent A so that the servo motor / amplifier 9 can maintain the metering time constant. Control. That is, the separation of the powder detergent A during the large throw time is performed by adjusting the large throw opening width so that the measuring time is constant. Then, the subsequent separation of the powder detergent A in the short throw time is adjusted according to the measurement result of the weight checker 5 so that the cut weight of the powder detergent A becomes the target weight. It has become.

When the metering completion signal j is output as described above, the filling machine sequencer 11 operates the cylinder 10 to open the opening / closing door 2a (step S7), and cleans the cut powder in the metering hopper 2. The agent B is dropped and filled in the tare 4. As a result, the weight of the cut powder detergent B measured by the load cell 3 rapidly decreases as shown by the characteristic i in FIG. And the filling machine sequencer 11
When it is determined from the weighed value of the load cell 3 that the weight has decreased to around "0", a near-zero signal m is output to the servo motor amplifier 9 (step S8).

In this way, the powdered detergent B
Is filled, the tare 4 is transferred from immediately below the weighing hopper 2 and the next tare 4 is carried in. Then, the weight of the carried out tare 4 is measured by the weight checker 5 and fed back to the filling machine sequencer 11 (step S9).

The filling machine sequencer 11 subtracts the pre-stored unit weight of the tare 4 from the weight value input from the weight checker 5, and calculates the weight of only the cut powder detergent B filled. And compare with the target weight. Then, it is determined whether or not the measured weight of the cut powder cleaning agent B is within the target weight range (step S10).

When the determination is "NO", that is, when it is determined that the weight of the cut powder detergent B actually measured by the weight checker 5 is out of the allowable weight range stored in the internal memory. The filling machine sequencer 11 sets the weight of the cut powder detergent B within the allowable weight range based on the deviation between the weight of the cut powder detergent B actually measured by the weight checker 5 and the target weight. The small opening width is corrected as described above (step S11).
As a result, the width of the small input opening when the powder cleaning agent A is cut next is changed, and the weight of the separated powder cleaning agent B falls within the allowable weight range.

On the other hand, the judgment in step S10 is "YE
In the case of "S", the filling machine sequencer 11 determines whether or not the weighing time is within the allowable weighing range (step S12). If the determination is "NO", the large opening width is corrected so that the weighing time falls within the allowable weighing range (step S13), and the large opening width is output according to the adjustment amount. The respective timer times of the timer and the output timer of the small throw opening width, that is, the large throw time and the small throw time are corrected (step S14). As a result, the weighing time, which is the time from the output of the weighing start signal b to the output of the weighing completion signal j, falls within the allowable weighing range.

[0032]

As described above, according to the powder filling apparatus and method according to the present invention, the following effects can be obtained. (1) The opening width of the shutter is forcibly and finely set by the servomotor, and the weight of the powder is measured by the load cell without change over time. Therefore, the variation in the weight of the cut powder can be suppressed, and the powder having the target weight can be cut constantly and stably. (2) Since the balance rod is not used unlike the conventional art, the edge of the supporting material for supporting the balance rod does not wear out, so that a decrease in the measurement accuracy due to long-term use can be suppressed. (3) It is conceivable that when the specific gravity of the powder changes, the weight of the cut powder changes. However, based on the weighed weight actually measured by the weight checker, the small opening width at the next cut is determined. Is corrected, so that the powder can be filled into the container with high weight accuracy. (4) The large opening width at the time of the next powder cutting is corrected so that the weighing time from the start of the powder cutting to the end of the cutting is constant, so that variations in the weighing time can be suppressed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a powder filling apparatus in one embodiment of a powder filling apparatus and method according to the present invention.

FIG. 2 is a perspective view showing a configuration example of a shutter which is a part of the powder filling device in one embodiment of the powder filling device and method according to the present invention.

FIG. 3 is a flowchart showing an operation of a filling machine sequencer in one embodiment of the powder filling apparatus and method according to the present invention.

FIG. 4 is a timing chart illustrating a powder filling method in one embodiment of the powder filling apparatus and method according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Powder storage hopper (powder storage means) 1a ... Shutter 1b ... Support point 1c, 1d ... Arc plate 1e ... Curved plate 1f ... Plate material 1g ... Groove 2 ... Metering hopper 2a ... … Opening door 3… Load cell 4… Tare 5… Weight checker 6… Servo motor 7… Encoder 8… Servo motor controller (control device) 9… Servo motor amplifier (control device) 10… ... Cylinder 11 ... Filling machine sequencer (control device) A ... Powder cleaner B ... Partition powder cleaner a ... Tare-in signal b ... Measurement start signal c ... Large input control signal d ... Small input Control signal j: Measurement complete signal m: Near zero signal

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Satoshi Sakuma 1-3-7 Honjo, Sumida-ku, Tokyo Inside Lion Engineering Co., Ltd.

Claims (2)

[Claims] 1. A powder filling device which cuts a fixed amount of powder and sequentially fills a container, comprising: a shutter provided at a lower end of a powder storing means; a servo motor for adjusting an opening width of the shutter; A load cell for measuring the weight of the powder dropped by the opening of the shutter; a weight checker for measuring the filling weight of the container filled with the powder; and A control device that controls the servomotor so that the opening width of the shutter gradually narrows from the large opening width to the small opening width with the passage of time, and separates the target weight of powder into the container. The control device corrects the large opening width at the time of the next powder cutting so that the measurement time from the start of the powder cutting to the end of the cutting is constant, and A powder filling device for correcting a small opening width of a shutter at the time of cutting the next powder based on the filling weight measured by the weight checker so that the powder cutting weight becomes a target weight. . 2. A powder filling method for cutting a fixed amount of powder into a container and filling the powder sequentially in a container, wherein a servo motor is used to change the opening width of the shutter from the large opening width to the small opening width of the stored powder. When cutting the powder having the target weight so as to gradually narrow the width, the large opening width is corrected so that the weighing time is constant, and the next cutting is performed, and the weighing weight of the actually cut powder is measured. The powder filling method is characterized in that the small opening width is corrected and the next cutting is performed so that the target opening weight becomes the target weight.