JPH018997Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for automatically measuring the moisture content of material flowing during a manufacturing process, particularly on a belt conveyor.

Conventionally, the moisture content of materials on a belt conveyor is determined by visual inspection or touch by an experienced worker, by taking a sample from the flowing material and measuring it using a drying method, or by using a high-frequency moisture measurement method. Information was sent upstream in the process to control moisture content in the material. However, methods that rely on the operator's intuition have many errors, dry methods are time-consuming, and even if there is a high-frequency measurement method, it is extremely inconvenient to manually collect and measure each sample, and the number of measurements required is extremely high. This makes quick process control difficult, especially when materials are flowing in large quantities at high speeds, and there has been a strong need for a moisture measuring device that can respond quickly to this problem.

This invention was developed to solve the above-mentioned problems, and the material is picked up by a hopper while being transferred from the upper belt conveyor to the lower belt conveyor.
By configuring the device to automatically prepare the material to be measured, measure moisture content, and release the material,
The purpose of the present invention is to provide a moisture measuring device that automates moisture measurement, makes it quick and accurate, continuously sends accurate information to upstream processes, and provides quick feedback to the manufacturing process.

The present invention provides a hopper with an openable bottom plate between an upper belt conveyor and a lower belt conveyor that transport the material to be measured, and the hopper has an upper level sensor that detects when the material to be measured has reached a predetermined upper limit. a device for inserting a moisture measuring electrode into the upper surface of the material to be measured with constant pressure at the same time as detecting the upper limit amount; a device for opening the bottom plate of the hopper after the moisture measurement is completed; This moisture measuring device is characterized in that it is provided with a lower level detector for detecting the lower limit amount, and a device for simultaneously detecting the lower limit amount and closing the bottom plate of the hopper.

Hereinafter, the present invention will be explained with reference to the drawings and examples. FIG. 1 is a configuration diagram for explaining an embodiment of the present invention. In the figure, a material 1 to be measured is supplied from an upper belt conveyor 2 to a hopper 4 provided between it and a lower belt conveyor 3. The hopper 4 has a bottom plate 5, and the bottom plate 5 is opened and closed by the expansion and contraction of the cylinder 6, and the material 1 is deposited in the hopper 4 and discharged onto the lower belt conveyor 3. An upper level detector 7 and a lower level detector 8 are attached to the hopper 4 at predetermined positions, respectively. Further, a vertical partition wall 9 is provided above the hopper 4 to separate the falling point of the material 1 from the measurement point, and an electrode 10 for moisture measurement is attached to this partition wall 9 via a cylinder 11. The electrode 10 moves up and down as the electrode 10 expands and contracts. Here, the partition wall 9 keeps the upper surface of the material at the moisture content measuring point constant and prevents the upper surface from fluctuating due to falling of the material 1. The upper level detector 7 detects that the moisture content of the material 1 in the hopper 4 has reached a predetermined upper limit, and at the same time operates the cylinder 11 using, for example, a level switch, lowers the electrode 10, and detects the upper surface of the material 1. It is configured to be inserted with a constant pressure.

In this case, the amount of material 1 deposited in the hopper 4 is always kept constant by the upper level detector 7, so that the density of the material 1 at the measurement point is constant.
The electrode 10 for moisture measurement is, for example,
This is something that has already been proposed in Utility Model Application No. 52-99507, etc., and in this embodiment, the electrode structure is as shown in FIG. Three rod-shaped ground electrodes 14 are arranged concentrically in parallel around the periphery of the insulating plate 12, and are attached to the insulating plate 12.
Further, in order to reduce the influence of stray capacitance, the earth side electrode 14 is made longer than the high voltage side electrode 13.

By configuring the moisture measuring electrode 10 in this way, it is easy to maintain a constant pressure on the material to be measured if it is pressed against the material to be measured with a force above a certain level, and as described above, the appropriate pressure can be maintained by the cylinder 11. As a result of being pressed, the material to be measured interposed between the peripheral earth side electrode 14 and the central high voltage side electrode 13 is placed in a substantially constant pressure state.
This satisfies the basic condition of the high-frequency moisture measurement method, that is, the moisture measurement electrode is kept under constant pressure in the material to be measured.
Note that the electrode 10 used in the present invention is not limited to one based on the high frequency measurement method, and may be an electrode based on other principles. When the moisture measurement is thus completed and the cylinder 11 is raised and the electrode 10 is returned to its original position, the cylinder 6 is operated, the bottom plate 5 is opened, and the material 1 is discharged onto the lower conveyor 3. There is.

When the upper surface of the material 1 in the hopper 4 gradually descends as it is discharged, and reaches a predetermined lower limit amount at which the measured material is not measured again, this is detected by a lower level detector and at the same time, for example, by a level switch. The cylinder 6 is operated, the bottom plate 5 is closed, and the material 1 in the hopper 4 is deposited again.

By repeating the above-described operations, the moisture content of the material transported by the belt conveyor is continuously measured.

By configuring the moisture measuring device as described above, the present invention detects when the material is deposited in the hopper and the moisture content can be measured. Insertion, moisture content measurement, release of material in the hopper, detection that the measured material in the hopper has been released to such a state that it cannot be measured again, simultaneous closure of the bottom plate of the hopper, redeposition of material, etc. It can be done automatically.

As described above, the device of the present invention includes a hopper with an openable and closable bottom plate between the upper belt conveyor and the lower belt conveyor that transport the material to be measured, and the hopper has an upper level detector configured as described above. ,
It is equipped with a device that raises and lowers the moisture measuring electrode, a device that opens and closes the bottom plate, a lower level detector, and a device that operates them in conjunction with each other, so it is possible to continuously remove moisture from flowing materials without the need for manpower. Since the measurement can be performed many times and automatically, and the measurement can be performed quickly without requiring much time, there is an effect that feedback to the manufacturing process can be quickly provided.

In addition, the upper level detector keeps the amount of material deposited constant during moisture measurement, and the density of the material to be measured at the measurement point becomes constant, so the moisture measurement value with the electrode inserted with a constant pressure becomes stable. It has the effect of being accurate.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram for explaining an embodiment of the present invention. 2 is a side view and a bottom view showing an example of the moisture measuring electrode shown in FIG. 1. FIG. 1... Material to be measured, 2... Upper belt conveyor, 3... Lower belt conveyor, 4... Hopper, 5... Bottom plate, 6, 11... Cylinder,
7... Upper level detector, 8... Lower level detector, 9... Partition wall, 10... Moisture measurement electrode, 1
2... Plate, 13... High voltage side electrode, 14...
Earth side electrode.

Claims (1)

[Scope of utility model registration request] A hopper with an openable bottom plate is provided between the upper belt conveyor and the lower belt conveyor that transport the material to be measured, and the hopper is provided with an upper level detector for detecting when the material to be measured has reached a predetermined upper limit amount. A device that simultaneously inserts a moisture measuring electrode into the upper surface of the material to be measured with constant pressure when the limit amount is detected, a device that opens the bottom plate of the hopper after the moisture measurement is completed, and a device that detects when the material to be measured has reached a predetermined lower limit amount. A moisture measuring device comprising: a lower level detector; and a device that simultaneously detects the lower limit amount and closes the bottom plate of the hopper.