JPH0780233B2 - Material feeder - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a material supplying apparatus for supplying a material to an extruder for molding a side molding made of synthetic resin or the like.

[0002]

2. Description of the Related Art Conventionally, this type of material supply device has utilized a screw conveyor, and this screw conveyor is connected to the material input port of an extruder so that pellets can be connected to the material input port. Materials such as powder were continuously supplied.

However, in the material supply device using the screw conveyor, the supply amount tends to vary.

Therefore, in the case of manufacturing an extruded product having no variation, it is necessary to precisely weigh and supply the material, and the vibration feeder and the weight of the vibration feeder are weighed,
In order to maintain a constant amount of material supplied from the vibration feeder to the extruder,
It is conceivable to configure the material supply device by using a control circuit that inputs a signal (measurement value) from the measuring device and adjusts the vibration mode of the vibration feeder.

However, even in the case where the vibration feeder, the measuring device, and the control circuit are used, the following problems occur.

That is, in the vibration feeder, the hopper for storing the material is fixed to the upper part of the trough so that the material can be supplied. Then, the vibrating feeder sequentially supplies the material stored in the hopper to the material input port of the extruder through the trough.

However, when the inside of the hopper becomes empty, it is necessary to separately supply the material into the hopper. At this time, the control circuit ignores the measured value from the measuring device because the weight of the material supplied into the hopper is unknown. Then, during that time, the vibrating feeder vibrates to supply the material so as not to completely stop the supply of the material to the extruder. However, if the control circuit ignores the measured value for a long time,
The molded product extruded from the extruder becomes a defective product over a long period of time.

The present invention is intended to solve the above-mentioned problems, and an object of the present invention is to provide a material supply device capable of supplying a constant amount of material to an extruder without causing defective products from the extruder. To do.

[0009]

SUMMARY OF THE INVENTION A material supply device according to the present invention supplies a material to a extruder while metering the material. Therefore, a vibrating feeder, a measuring device for measuring the vibrating feeder, and the extruding device from the vibrating feeder. A control circuit for adjusting a vibration mode of the vibration feeder by inputting a signal from the weighing device in order to keep the amount of the material supplied to the machine constant, and the vibration feeder moves the material. And a hopper connected to the material supply port of the extruder and fixed to the upper part of the trough to allow the stored material to flow into the trough. When the material in the hopper is below the minimum storage weight, 1/2 to 1 / of the minimum storage weight
4 is provided with a lot feeding device for feeding the material having a weight within the range of 4 into the hopper, and the lot feeding device is held in a system different from that of the vibrating feeder and the weighing device.

[0010]

In the material supply device according to the present invention,
When the stored weight of the material in the hopper is less than the minimum stored weight,
A material having a weight within the range of 1/2 to 1/4 of the minimum storage weight is supplied from the lot supply device into the hopper of the vibration feeder.

Therefore, the material is supplied into the hopper by dividing it into pieces by the lot supply device. At that time, when the material is supplied into the hopper, the control circuit is in a state of ignoring the measured value from the measuring device, and in a non-controlled state, the trough of the vibrating feeder vibrates and sends the material to the extruder. However, the time during which the measured value is ignored is the material supply time into the hopper, and since the lot supply device divides the material into the hopper and supplies the material into the hopper, the number of times is large, but each is short,
Even if it is not controlled by the control circuit, the trough can vibrate constantly and supply a substantially constant amount of material to the extruder.

Therefore, the material supply apparatus according to the present invention can supply a certain amount of material to the extruder without causing defective products from the extruder.

Further, the lot feeder of the present invention is held in a separate system from the vibrating feeder and the weighing device, and when the material is fed to the lot feeder itself, it gives unnecessary impact to the vibrating feeder and the weighing device. Therefore, it is possible to prevent the fixed amount of the vibration feeder from being supplied to the extruder.

The weight supplied by the lot supply device into the hopper at a time is 1/2 to the minimum storage weight in the hopper.
The reason why the range is 1/4 is that if it is less than 1/4,
If the ratio of the non-control time becomes large and exceeds 1/2, the thickness of the material layer in the trough rapidly increases due to the lot supply, and the accuracy of the weight supplied to the extruder deteriorates.

Furthermore, in the material supply apparatus of the present invention,
An interference member that interferes with the material falling from the lot supply device can be arranged between the hopper and the lot supply device. In this case, when the material is supplied from the lot supply device into the hopper, the impact of the falling material is reduced by the interference member, so that the measuring device for measuring the vibration feeder can be prevented from malfunctioning.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

As shown in FIGS. 1 and 2, the material supply device M of the embodiment has a vibration feeder 1, a weighing device 9, and a control circuit 1.
0 and a lot supply device 11 are provided.

The vibration feeder 1 includes a vibrating trough 2 and
A hopper 3 fixed to the upper part of the trough 2 for dropping the stored material P into the trough 2. The trough 2 is supported by a plurality of lower leaf springs 4, and a transformer 5 is fixed to the leaf springs 4. Then, the trough 2 vibrates as the transformer 5 attracts and repels the leaf spring 4. Further, this transformer 5 has a control circuit 1
It is electrically connected to 0 and adjusts a vibration mode such as an amplitude for vibrating the leaf spring 4 and the trough 2 according to an electric signal from the control circuit 10.

A hose S connected to the material input port O of the extruder E is connected to the supply end side of the material P of the trough 2.

The weighing device 9 comprises a load cell,
The load cell 9 is electrically connected to the control circuit 10 and also supports and fixes the lower portion of the leaf spring 4.

The vibration feeder 1 and the load cell 9 are supported by a support frame 8 disposed below the load cell 9. Further, the support frame 8 straddles the extruder E and is fixed to the installation surface H of the extruder E.

Between the load cell 9 and the support frame 8, in order to prevent the load cell 9 from being greatly affected by the vibration of the installation surface H, the weight 6 located on the lower surface of the load cell 9 and the weight 6 are placed. The anti-vibration plate 7 located on the lower surface is arranged. In the load cell 9, the influence of the vibration of the vibration feeder 1 is removed by an electric filter.

The control of the control circuit 10 for supplying a constant amount of the material P from the trough 2 will be described. The control circuit 10 sends an electric signal (measurement value) from the load cell 9 corresponding to the weight of the vibration feeder 1. The weight of the residual material of the material P that has been input and discharged from the trough 2 is calculated, and the supply weight of the material P is calculated from the change in the weight of the residual material per unit time. Then, the calculated value is compared with the target value, and the vibration mode of the transformer 5 is adjusted so that the deviation becomes zero. By the way, in the case of the embodiment, the extruder E
The supply amount of the material P to be supplied to the material supply port O is 40 to 5
It is set to a predetermined constant value within the range of 0 g / s.

The control circuit 10 also includes a hopper 3 which will be described later.
While the material P is being supplied therein, the material supply weight is unknown, so the measured value from the load cell 9 is ignored. More specifically, a shutter 15 to be described later opens and closes until the suspension of the material P supplied into the hopper 3 settles down (in the embodiment, the opening and closing of the shutter 15 takes about 2 seconds, and the suspension settles down about 1 second). 0.5 seconds, a total of about 3.5 seconds), ignoring the measured value from the load cell 9. Then, during that time, the transformer 5 is operated in the vibration mode immediately before the material P is supplied into the hopper 3. By the way, the reason for continuing the operation of the transformer 5 in this way is that if the material supply to the extruder E is completely stopped, the molded product extruded from the extruder E will be a defective product for a long time. Because it will be.

The lot supply device 11 includes a storage pipe 12 arranged above the hopper 3 of the vibration feeder 1 and a storage pipe 12.
And a suction hopper 17 connected to the upper part of the. The lot supply device 11 is supported by a support frame 21 connected to the lower surface of the storage pipe 12,
The support frame 21 is fixed to the extruder E as a system separate from the support frame 8.

The storage tube 12 is made of a transparent material such as a glass tube, and photoelectric switches 13 and 14 electrically connected to the control circuit 10 are fixed to the upper and lower portions of the outer peripheral surface. A shutter 15 that is opened and closed horizontally by an air cylinder 16 is arranged below the storage pipe 12.

Further, two round bars 22 which are held by the support frame 21 and extend in the horizontal direction are arranged below the shutter 15 and between the hopper 3 of the vibration feeder 1 (see FIG. 3). These round bars 22 are the storage tubes 12
It is an interference member that reduces the impact of the material P falling from the inside into the hopper 3.

In the case of the embodiment, the photoelectric switch 1
When 3 is turned off, that is, when the material P is sufficiently filled in the storage pipe 12, the weight of the stored material P is 2 kg. On the other hand, the minimum storage weight of the material P in the hopper 3 of the vibration feeder 1 is set to 4.5 kg. In addition, hopper 3
The maximum allowable weight is 10 kg.

The air cylinder 16 has a control circuit 10
Is configured to operate by The operation of the air cylinder 16 will be described. The material P in the hopper 3 is
Is equal to or less than the minimum storage weight, and the photoelectric switch 13 is turned off so that the material P is sufficiently filled in the storage pipe 12, the control circuit 10 which inputs the electric signal from the load cell 9 and the photoelectric switch 13 Therefore, the air cylinder 16
A predetermined valve to switch to operate to open the shutter 15. Then, when the photoelectric switch 14 is turned on and the material P is emptied in the storage tube 12, the control circuit 10 that has input the electric signal from the photoelectric switch 14 causes the shutter 15 to be closed again. Operate.

The suction hopper 17 is divided into two upper and lower chambers 17A and 17B by a rubber plate 19 disposed inside. The rubber plate 19 has an opening 19a at the center which narrows downward. Also, the rubber plate 19
The upper chamber 17A separated by the above is provided with a connection port 18 capable of communicating with the material can C, and a vacuum pump 23
The connection pipe 20 connected to the is connected.

The vacuum pump 23 is used for transferring the material P in the supply canister C into the upper chamber 17A. When the vacuum pump 23 operates, the inside of the upper chamber 17A becomes negative pressure, and the material P The material P in the can C is sucked into the upper chamber 17A. Then, thereafter, the material P sucked into the upper chamber 17A opens the opening 19a of the rubber plate 19 by its own weight and drops into the storage can 12.

The vacuum pump 23 is electrically connected to the control circuit 10 so as to be controlled, and the photoelectric switch 13 is turned off except when the shutter 15 is open, that is, the material inside the storage can 12. It continues to operate until P is fully filled, and its operation continues with the vibration feeder 1.
This is continued until the weight of the material in the hopper 3 reaches the over level (6 kg in the embodiment).

Next, an operation mode of the material supply apparatus M of the embodiment will be described. First, the hopper 3 of the vibration feeder 1
When the material P is sufficiently stored therein (when the material P stored in the hopper 3 is 4.5 kg or more), the control circuit 10 corresponds to the weight of the vibration feeder 1 from the load cell 9. The weight of the residual material of the material P discharged from the trough 2 is calculated based on the electric signal (measured value), and the supply weight of the material P is calculated from the change in the weight of the residual material per unit time,
The calculated value is compared with the target value, and the vibration mode of the transformer 5 is adjusted so that the deviation becomes zero. Therefore, a certain amount of the material P can be supplied to the material supply port O of the extruder E.

After that, when the weight of the material P in the hopper 3 becomes equal to or less than the minimum storage weight (4.5 kg), the control circuit 10 determines a predetermined value based on the electric signals from the load cell 9 and the photoelectric switch 13. Air cylinder 16 by opening and closing the valve
Is operated to open the shutter 15 as shown in FIG. At that time, the storage tube 1 is opened by opening the shutter 15.
2 kg of the material P stored in 2 drops from the lot supply device 11 into the hopper 3. At that time, the falling material P hits the round bar 22 as two interference members before being accommodated in the hopper 3, so that the impact given to the hopper 3 can be reduced.

At the same time when the shutter 15 is opened,
The control circuit 10 ignores the measured value from the load cell 9,
An electric signal is output to the transformer 5 so that the trough 2 of the vibration feeder 1 vibrates in the vibration mode in the state immediately before the shutter 15 is opened, that is, immediately before starting to ignore the measured value from the load cell 9.

Further, when the photoelectric switch 14 is turned on and the material P is emptied in the storage pipe 12, the photoelectric switch 1
The control circuit 10 receiving the electric signal from the control circuit 4 closes the shutter 15 via the air cylinder 16.

After that, after the floating of the material P supplied into the hopper 3 has settled down, the control circuit 10 starts to take in the measured value from the load cell 9, adjusts the vibration mode of the transformer 5, and adjusts the trough 2 to a constant amount. The material P is supplied to the material supply port O of the extruder E.

On the other hand, in the empty storage tube 12, except for the case where the control circuit 10 has the shutter 15 open,
The vacuum switch 23 is controlled to continue to operate until the photoelectric switch 13 is turned off, that is, the material P is sufficiently filled in the storage can 12. Therefore, the material P from the material can C sucked into the upper chamber 17A of the suction hopper 17 is sufficiently filled in the storage tube 12 through the opening 19a of the rubber plate 19.

This control is controlled so as to be continued until the weight of the material P in the hopper 3 reaches an overlevel (6 kg in the case of the embodiment). The weight supplied from the pipe 12 into the hopper 3 is 2 kg, and a single supply from the storage pipe 12 supplies the hopper 3 with a minimum reservoir weight of 4.5 kg to an overlevel of 6 kg. Therefore, the operation of the vacuum pump 23 is once for a predetermined time until the material is supplied to the next hopper 3 after the material is supplied to the hopper 3 once.

In the material supply device M of the embodiment, the material is supplied into the hopper 3 by the lot supply device 11 in a divided manner. That is, when the material is supplied into the hopper 3, the control circuit 10 ignores the measured value from the load cell 9, and the trough 2 of the vibration feeder 1 vibrates in the uncontrolled state to move the material P to the extruder E. send. However, the time during which the measured value is ignored is the time for supplying the material into the hopper 3, and since the lot supply device 11 subdivides and supplies the material P into the hopper 3, the number of times increases. However, each of them is short (about 3.5 seconds in the embodiment), and even if the control circuit 10 does not successively control, the trough 2 vibrates constantly and supplies a substantially constant amount of the material P to the extruder E. Therefore, the generation of defective products in the extruder E can be suppressed as much as possible.

Conventionally, when the inside of the hopper becomes empty, 500 Kg of material P, which is almost the full capacity of the hopper, is supplied, and the control circuit does not control for about 30 seconds. After the material was supplied, a defective product was generated from the extruder E for a long time of 4 minutes. Further, a load cell (measuring device) that has a large allowable load is required, which causes a problem of low measuring accuracy.

Further, the lot feeding device 11 of the embodiment is supported by the support frame 21 and is held separately from the vibrating feeder 1 and the load cell 9, and the material P is fed to the lot feeding device 11 itself by the material can C. It is possible to prevent the vibration feeder 1 and the load cell 9 from being impacted unnecessarily when being supplied from the above, and to prevent the vibration feeder 1 from being quantitatively supplied to the extruder E.

Further, in the material supply device M of the embodiment, a round bar 22 as an interference member which interferes with the material P falling from the lot supply device 11 is arranged between the hopper 3 and the lot supply device 11. When the material is supplied from the lot supply device 11 into the hopper 3, the impact of the falling material P is reduced by the round bar 22, so that the load cell 9 for measuring the vibration feeder 1 can be prevented from malfunctioning. In particular, the load cell 9 needs to have a low allowable load (for example, 15 kg (material weight: 10 kg)) in order to improve weighing accuracy, and is weak against a dynamic load compared to a static load, and the above configuration is durable. It is effective in terms of sex.

In the embodiment, in the lot supply device 11, the case where the material P is supplied into the suction hopper 17 by using the vacuum pump 23 is shown, but the screw conveyor is used instead of the vacuum pump 23. Material P into hopper 17
May be supplied. Further, in this case, the material P is directly supplied to the storage pipe 12,
May be composed of a measuring cell.

Furthermore, in the lot supply device 11 of the embodiment, the photoelectric switch 13 or 14 is used for filling the material P or empty state.
Although the case where the detection is performed is described above, a capacitance type sensor or the like may be used instead.

Furthermore, the lot supply device 11 of the embodiment.
Then, when the material P is supplied from the storage pipe 12 to the hopper 3,
Although the case where the shutter 15 that slides in the horizontal direction is used is shown, a shutter that opens and closes by rotating may be used. By the way, the slide type shutter 15 has an effect that it is difficult to bite the material P, as compared with a shutter that rotates and opens and closes.

Further, in the embodiment, the lot supply device 11
However, assuming that the weight of the material P supplied into the hopper 3 at one time is 2 kg, it is about 44% of 4.5 kg of the minimum storage weight in the hopper 3.
The case is shown. However, the supply to the inside of the hopper 3 once may be 2.25 to 1.125 Kg, which is in the range of 1/2 to 1/4 of 4.5 Kg of the minimum storage weight. In this case, if it is less than 1.125 Kg, the ratio of the non-control time becomes large, and if it exceeds 2.25 Kg, the thickness of the material layer in the trough rapidly increases due to the lot supply, so that the accuracy of the weight supplied to the extruder is improved. Because it gets worse. And, of course, this weight can be dealt with by arbitrarily changing it into a predetermined range if the storage volume of the hopper 3 changes.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of the present invention.

FIG. 2 is a front view of the embodiment.

FIG. 3 is a plan view showing a round bar (interference member) of the embodiment.

FIG. 4 is a view showing a state in which a material is supplied into the hopper of the vibration feeder of the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Vibration feeder, 2 ... Trough, 3 ... Hopper, 9 ... (Measuring device) load cell, 10 ... Control circuit, 11 ... Rot supply device, M ... Material supply device, P ... Material, E ... Extruder, O ... Material Supply port.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display area // B65G 27/00

Claims (1)

[Claims] 1. A vibrating feeder, a metering device for weighing the vibrating feeder, and a supply amount of the material fed from the vibrating feeder to the extruder are kept constant in order to supply the material while being metered to the extruder. Therefore, a control circuit for inputting a signal from the measuring device to adjust the vibration mode of the vibration feeder is provided, and the vibration feeder moves the material and is connected to the material supply port of the extruder. When,
A material supply device comprising: a hopper fixed to the upper part of the trough to allow the stored material to flow into the trough, wherein the material in the hopper is below the minimum storage weight above the hopper. 1 / of the minimum storage weight
A lot supply device is provided for supplying a material having a weight within the range of 2 to 1/4 into the hopper, and the lot supply device is
A material supply device, which is held in a system separate from the vibration feeder and the weighing device.