JPS6212281Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a moisture measuring device for powder and granular material that can accurately measure the moisture in a low moisture region of powder and granular material online.

Generally, a two-color infrared moisture meter is used as an example of a device that continuously measures the moisture content of powder or granular materials. This two-color infrared moisture meter makes use of the fact that infrared rays of a specific wavelength are absorbed by water, and two types of light are applied to the object to be measured: one at a wavelength that is absorbed by moisture, and one at a comparison wavelength that is not absorbed. , the ratio of the energy of the light that is reflected and returned is determined by comparison calculations, and the moisture content on the surface of the material is instantaneously measured. Therefore, it has features such as non-contact, non-destructive, and non-destructive sampling of the object to be measured, and the ability to measure moisture online. Such a moisture meter is used by being placed in a moisture measuring device as shown in FIG.
That is, an opening 3 is provided at the top of the tip of a screw feeder 2 horizontally connected to the bottom of the crusher 1,
A moisture meter 4 is attached to the flange formed in this opening 3.
, with its moisture detection end 5 facing downward,
A discharge tube 7 is provided at the discharge port 6 provided at the bottom of the tip of the screw feeder 2, a valve 8 is provided on the discharge tube 7, and the powder pulverized by the crusher 1 is sent to the discharge port 6 side by the screw 9. The powder that has reached the powder measuring section 10 is continuously measured by a moisture meter 4, and is discharged downward from the discharge tube 7 through the discharge port 6 and the valve 8.

However, in such a conventional moisture measuring device, the powder measuring section 10 located directly below the moisture meter 4 has an uneven top surface as shown in FIG. 2 when viewed from the direction of the arrow in FIG. It is deposited on a slope. The shape of this powder deposit is constantly changing as the screw 9 rotates. Therefore, the moisture detection end 5 of the moisture meter 4 and the powder measurement section 10
Naturally, the distance between The drawback was that it did not hold well even when held, and the measurement accuracy was low. Incidentally, on a trial basis, the distance between the powder measuring section 10 and the moisture meter 4 was kept constant, and the angle of inclination of the top surface of the powder measuring section 10 was varied from 0° to 60°, and the water content of powder with a water content of 1% was determined. Fig. 3 shows the actual measurement results of the moisture content measured by the moisture meter 4. According to the measurement results shown in Figure 3, when the angle of inclination of the measurement surface of the powder was 0°, the measured moisture content was an accurate value of 1.0%, but when the angle of inclination was 60°, The moisture content was measured at 1.3%, which is 30% higher than the actual moisture content. In addition, the inclination angle of the top surface of the powder measuring section 10 is set to 0°, and the distance between the powder measuring section 10 and the moisture meter 4 is set from 150 mm.
Figure 4 shows the results of actually measuring the moisture content of powder with a moisture content of 1% by changing the diameter to 330 mm using moisture meter 4. According to the measurement results shown in Fig. 4, when the measurement distance was 200 mm, the measured moisture content was an accurate value of 1.0%, but when the measurement distance was 150 mm, it was 0.8%.
At 330mm, it shows a value of 1.5%, and due to the difference in measurement distance, the measured value is 50% higher than the actual moisture content.

This idea was made in view of the above circumstances,
A leveling plate is rotatably installed between the moisture meter and the object to be measured, so that the optical path of the light emitted from the moisture meter and reflected by the object to be measured is not blocked when measuring the moisture content of the object to be measured. It is an object of the present invention to provide a moisture measuring device for powder and granular material that can significantly improve the measurement accuracy in measuring the moisture content in the low moisture region of powder and granular material by forming and connecting a rotational drive mechanism thereto. .

An example of this invention is shown below in Figures 5 to 10.
This will be explained based on the diagram. In this embodiment, parts that are substantially the same as those in the conventional example are given the same reference numerals, and the explanation thereof will be omitted.

A lid 11 is provided at the end of the screw feeder 2 on the discharge port 6 side, and a bearing 1 is provided on the lid 11.
2 is provided. Further, a bearing 13 and a rotational drive mechanism (motor) 14 are provided on a base (not shown) located on the same axis of the bearing 12. A drive shaft 15 is connected to the motor 14, and the drive shaft 15 is rotatably supported by bearings 12 and 13.

A leveling plate 16 is provided on the drive shaft 15 so as to be rotatable about an axis perpendicular to the optical axis of light emitted from the moisture meter 4 toward the portion to be measured 10 . As shown in FIGS. 6 to 10, this leveling plate 16 aligns the optical axis of the light into the object 18 (powder) to be measured with the center rod 17 of the drive shaft 15 as the center. It consists of an arcuate plate with a radius that allows it to intervene orthogonally and is slightly smaller than the radius of the inner peripheral surface of the screw feeder 2, and is connected to the arm 19 of the drive shaft 15 via a connecting plate 20. ing. Arm 19 for center rod 17
are provided perpendicularly to each other, and the connecting plate 20 is provided at an angle. Further, a notch 21 is formed in the leveling plate 16 so that the end face of the leveling plate 16 is inclined with respect to the center rod 17 and substantially along the connecting plate 20, located on the screw 9 side.

A fixed position detector 22 is attached to the drive shaft 15 and located between the bearings 12 and 13. This fixed position detector 22 is connected to a leveling plate 16 as described later.
is rotated to a predetermined position so as not to block the optical path of the light emitted from the moisture meter 4 and reflected by the object to be measured 18, it emits a detection signal indicating that there is no obstacle in the optical path of this light. The moisture meter 4 is operated in conjunction with this detection signal.

When measuring the moisture content of the object to be measured 18, the valve 8 is opened, the crusher 1 is operated, and the screw 9 and motor 14 are rotated. Then,
The leveling plate 16 rotates, and the screw 9 sends the object to be measured 18 to the powder measuring section 10, and the upper surface of the object to be measured 18 is leveled by the leveling plate 16. The upper surface of the part to be measured 10 is almost perpendicular to the optical axis of the light when the light is emitted from the moisture meter 4 toward the part to be measured 10, and the angle of inclination of the moisture meter 4 with respect to the moisture detection end 5 is 0. It becomes ゜. Further, the distance from the moisture detection end 5 to the surface of the portion to be measured 10 is always constant. When the leveling plate 16 rotates to a predetermined position as shown in FIG. The optical path of the emitted light will not be blocked. At this time, the connecting plate 20,
The arm 19 and the center rod 17 are located at positions where they do not block the optical path of the light emitted from the moisture meter 4 toward the part to be measured 10. When this happens, the leveling plate 16 is located at a predetermined position, and the fixed position detector 22 detects that there is no obstacle in the optical path of the light emitted from the moisture meter 4 to the part to be measured 10. The moisture meter 4 emits light toward the part to be measured 10 in conjunction with the signal,
This light hits the part to be measured 10, and a part of the light is reflected and returns to the moisture meter 4, thereby causing the part to be measured 18
The moisture content is measured. The powder scraped up by the leveling plate 16 passes through the connecting plate 20 and is sent from this connecting plate 20 to the discharge port 6 side, and from this discharge port 6 passes through the valve 8 provided at the lower part of the discharge pipe 7. It is housed in a container (not shown). Note that when the rotating state of the leveling plate 16 in the screw feeder 2 and the leveling state of the object to be measured 18 by the leveling plate 16 are observed from the direction of the arrow X in FIG. 5, they are roughly shown in FIG. 10. Therefore, when measuring the moisture content of the object to be measured 18, the angle of inclination of the top surface of the part to be measured 10 with respect to the moisture detection end 5 of the moisture meter 4 is always constant at approximately 0°, and from the moisture detection end 5 to the top surface of the part to be measured 10. It can be seen that the distance is always constant. The line between vertical lines A and B shown in FIG. be done.

As explained above, according to this invention, a leveling plate is rotatably provided between the moisture meter and the object to be measured,
A leveling plate is formed so that the optical path of the light emitted from the moisture meter and reflected by the object to be measured is not blocked when measuring the moisture content of the object to be measured, and a rotational drive mechanism is connected to this. When measuring the moisture content of an object, the top surface of the part to be measured does not always tilt with respect to the moisture detection end of the moisture meter, and the distance from the moisture detection end to the top surface of the part to be measured is always constant. , it is possible to greatly improve the accuracy of moisture measurement in low moisture regions of objects to be measured, and furthermore, this invention can be widely applied online.

[Brief explanation of the drawing]

Fig. 1 is a schematic cross-sectional view showing an example of a conventional moisture measuring device for powder and granular materials, Fig. 2 is a view of the main part of Fig. 1 in the direction of arrows, and Fig. 3 shows the inclination angle of the upper surface of the part to be measured. Figure 4 shows the variation in the measured moisture content of the measured object as the distance from the moisture detection end of the moisture meter to the top surface of the measured object changes. FIG. 5 is a schematic sectional view showing an embodiment of the invention; FIG. 6 is a partially omitted schematic perspective view showing the state of one of the leveling plates during rotation; FIG. 7 is a diagram showing fluctuations in measured values; is a view in the direction of the arrow in Fig. 6, Fig. 8 is a view in the direction of the arrow in Fig. 6, Fig. 9 is a view in the direction of the arrow in Fig. 6, and Fig. 10 is a view in the direction of the arrow in Fig. 6.
The figure is a schematic view taken in the direction of the arrows in FIG. 4... Moisture meter, 5... Moisture detection end, 10... Powder measuring section, 14... Rotation drive mechanism (motor), 1
5... Drive shaft, 16... Leveling plate, 18... Measured object, 20... Connection plate, 21... Notch.

Claims (1)

[Scope of utility model registration request] Emits light toward the object to be measured consisting of powder and granules,
A moisture meter that measures the moisture of the object to be measured using reflection of the light by the object to be measured, and an optical axis of the light between the moisture meter and the object to be measured located directly below the moisture meter. The light source is provided rotatably around an axis perpendicular to the light beam, and during rotation it intervenes in the object to be measured perpendicular to the optical axis of the light, and rotates to a predetermined rotational position when measuring the moisture content of the object to be measured. a leveling plate formed so as not to block the optical path of the light; and a rotational drive mechanism connected to the leveling plate so as not to block the optical path of the light during moisture measurement of the object to be measured. A moisture measuring device for powder and granular materials.