JP3963045B2 - Apparatus for measuring moisture content by microwave and tea process control method using the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for measuring the moisture content of tea leaves and the like using microwaves, and in particular, there is little variation for each measurement, and furthermore the moisture content by microwaves can be reduced compared to conventional devices. The present invention relates to a measurement method, an apparatus therefor, and a tea process control method using these.
[0002]
BACKGROUND OF THE INVENTION
The processing of tea leaves in a tea factory has a substantial number of processes that substantially promote the drying of tea leaves. Specifically, from the steamed leaves of about 360% moisture content (based on the weight of tea leaves with zero moisture). Finally, it is subjected to cocoon drying until crude tea with a moisture content of about 5% is obtained.
[0003]
The process for this includes the leaf-making process, the rough-cooking process, the twisting process, the mid-stitching process, the mid-stitching process, the refinement process, and the drying process. This is an important factor in the operation of tea making equipment to obtain good quality products.
[0004]
Therefore, recently, as a device for grasping the moisture content, an electric resistance type moisture meter, a microwave type moisture meter, a near infrared type moisture meter, etc. are used. There was room for improvement.
First, the electric resistance type moisture meter measures the electrical resistance of the tea leaf by positioning the tea leaf between the electrodes. In principle, it can only measure the moisture on the tea leaf surface, so the measurement result tends to depend on the surface resistance. Therefore, it is inaccurate and it is difficult to grasp the water content of the entire tea leaf, and it is insufficient for use as data for controlling the tea production line.
In addition, if a voltage higher than a certain level is applied due to the moisture content of the tea leaves, dielectric breakdown will occur and measurement will be impossible. Data processing is complicated.
[0005]
In addition, since the microwave moisture meter requires a load cell, which is a tea leaf weight measuring device, the configuration of the measurement system cannot be denied.
[0006]
The near-infrared moisture meter can measure the moisture up to the inside of the tea leaf slightly than the electric resistance-type moisture meter, but in principle can only measure the moisture on the tea leaf surface. In addition, since the near-infrared irradiation range is very narrow, there is a drawback that only a small part of the sample can be measured. Furthermore, since the near-infrared moisture meter is expensive, its versatility is poor.
[0007]
[Technical problem to be solved]
The present invention has been made from such a background, and does not require weight measurement means as in the case of conventional devices, can reduce the cost of the entire device, and can improve the measurement accuracy. The technical problem is to develop a method for measuring moisture content using microwaves, a device therefor, and a tea process control method using them.
[0008]
[Means for Solving the Problems]
In other words, the microwave moisture content measuring apparatus according to claim 1 forms a transmission path composed of a microstrip line between a microwave transmitter and a receiver, and this transmission path is located in a tea leaf housing portion of the sampling apparatus. Let In a device for measuring moisture content, The tea leaf accommodating portion includes a bottom plate, a pair of side plates rising on both sides of the bottom plate, a top plate provided to face the bottom plate, and a shutter frame and a back plate rising before and after the bottom plate. The microstrip line is disposed on one or both of the pair of side plates, or one or both of the top plate or the bottom plate, and the back plate extends along the side plate and the bottom plate. Or a plate frame member provided with the microstrip line, or another plate frame member facing the plate frame member provided with the microstrip line, or It is characterized in that a pressing plate is formed by making both movable.
According to this invention, it is possible to measure the moisture content of the tea leaves accommodated in the tea leaf accommodating portion with high accuracy without requiring the weight measurement of the tea leaves.
Also, Since the arrangement position of the microstrip line can be selected in accordance with the installation position of the moisture content measuring device limited by the tea making device, versatility can be enhanced.
In addition, a plurality of measurement data can be obtained by measuring the tea leaves of the same sample with two microstrip lines attached at two locations, and the measurement accuracy is improved.
Also, By pressing the tea leaves taken into the tea leaf container with the pressing action plate, the tea leaf density can be made more uniform for each measurement, so that more accurate measurement can be performed. Since it can discharge | emit, it can measure the moisture content of the tea leaf in process by attaching with respect to the apparatuses (rough grinder etc.) which comprise a tea production line.
[0009]
And claims 2 The microwave moisture content measuring device described above is characterized in that, in addition to the above requirements, the strip conductor in the microstrip line is covered with a protective plate having an appropriate thickness.
According to this invention, since the tea leaf does not directly touch the strip conductor, the electric field generated between the strip conductor and the conductor plate is not disturbed, and the moisture content can be measured with high accuracy. Further, corrosion, wear and damage of the strip conductor can be prevented.
[0010]
Further claims 3 The microwave moisture content measuring apparatus described above is characterized in that, in addition to the above requirements, an air bag is provided on the pressing action plate.
According to the present invention, the tea leaves are pressed against the microstrip line by the airbag, so that the density of the tea leaves for each measurement is made more uniform, so that more accurate measurement can be performed.
[0011]
Further claims 4 In addition to the above requirements, the microwave moisture content measuring apparatus described is provided with a cleaning mechanism for removing tea leaves, moisture, etc. adhering to the microstrip line.
According to this invention, since the tea leaves for the previous measurement do not remain on the microstrip line, highly accurate measurement can be performed.
[0012]
Further claims 5 In addition to the above-described requirements, the microwave moisture content measuring apparatus described above includes a mechanism that can change the position where the microstrip line faces the tea leaves.
According to the present invention, the reliability of data is increased by continuously performing measurement with different measurement locations on the same sample, and more accurate measurement can be performed.
[0013]
And claims 6 The tea making process control method using the described microwave moisture content measuring device is formed by forming a transmission path between a microwave transmitter and a receiver with a microstrip line, before processing by a tea manufacturing apparatus, after processing, or processing The tea leaf inside is positioned facing this microstrip line, and the moisture content of the tea leaf is calculated from the difference in the reception level caused by the absorption of microwaves by the moisture contained in the tea leaf, and according to this moisture content And determining when to take out tea leaves from tea making equipment.
According to this invention, the moisture content of the tea leaf is measured with high accuracy, and the tea leaf processing status is determined based on this value, so that the processing status of the tea leaf can be optimized, Quality processed tea leaves can be obtained.
The above problems can be solved by using the configuration of the invention described in each of the claims as a means.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the structure of the moisture content measuring apparatus using microwaves according to the present invention will be described, and then the moisture content measuring method using microwaves and the tea process control method using these will be described.
As shown in FIG. 1, the moisture content measuring device 1 of the present invention is configured integrally with a sampling device 2 provided in a side plate portion 21 of a roughing machine 20 in a tea factory as an example. Of course, as for the location where the moisture content measuring device 1 is disposed, an appropriate position such as the front surface of the roughing machine 20 can be selected.
[0015]
First, the sampling device 2 will be described. In this device, a tea leaf accommodating portion 3 is formed as shown in FIG. 2, and the tea leaf accommodating portion 3 is a pair of plates that rise on both sides of the bottom plate 4 and the bottom plate 4. In a rectangular space defined by plate frame members including the side plates 5R and 5L, the top plate 8 provided opposite to the bottom plate 4, and the shutter plate 6 and the back plate 7 rising before and after the bottom plate 4. is there. A slight clearance is provided between the bottom plate 4, the back plate 7 and the side plate 5.
In the following description, “front” means the roughing machine 20 side to which the sampling device 2 is attached, and “rear” means the opposite direction.
[0016]
The back plate 7 is configured to be movable back and forth along the side plate 5 and the bottom plate 4 to form a discharge action plate, and one side plate 5 (the side plate 5R as an example in the present embodiment) is used as the bottom plate 4. Along with the other side plate 5 (in this embodiment, as an example, the side plate 5L), the pressing plate is configured to be movable so as to approach and separate.
For this reason, the cylinders 7a and 5a are fixed to the housing 9 using appropriate brackets, and these rods are fixed to the back surface of the back plate 7 and the back surface of the side plate 5R, respectively.
[0017]
Further, a nylon brush 17 as an example of a cleaning mechanism is provided on one side (side plate 5L side) of the back plate 7 over the entire longitudinal direction. As the cleaning mechanism, an air purge mechanism including a nozzle for blowing compressed air as appropriate, in addition to the nylon brush 17, rubber spatula, cloth, etc., which wipes the upper surface of the side plate 5L by the movement of the back plate 7 is adopted. You can also.
[0018]
The shutter plate 6 opens and closes the tea leaf housing part 3 by moving up and down along the front end surfaces of a pair of opposed side plates 5. A rod of a cylinder 6 a fixed to the housing 9 is attached to the shutter plate 6. It is fixed to the upper end surface.
[0019]
Further, a microstrip line 10 is disposed on the surface of the other side plate 5L facing the movable side plate 5R on the side of the tea leaf accommodating portion 3, and the microstrip line 10 has a strip conductor 12 side. The surface is covered with an appropriate protective plate 16 made of an insulating material. In the present embodiment, an acrylic plate having a thickness of 0.4 mm is used as the protective plate 16.
[0020]
Hereinafter, the above-described microstrip line 10 will be described in detail.
The microstrip line 10 is a microwave transmission line that is structurally formed by removing one of the conductor plates of a symmetrical strip line, but that can be considered as a modification of two parallel wires electrically. . 3A, the strip-shaped strip conductor 12 is positioned above the conductor plate 11 as shown in FIG. 3A. In order to hold the strip conductor 12, the conductor plate 11 and the strip conductor are arranged. 12 is formed by inserting a dielectric 13 as a spacer.
[0021]
As a material for the conductor plate 11 and the strip conductor 12, it is preferable to use a metal having high conductivity such as copper or iron, but a metal having excellent corrosion resistance such as stainless steel can also be used. The dielectric 13 is made of glass fiber, ceramic, or the like containing silicone, fluororesin, epoxy resin or the like.
[0022]
In the present embodiment, since a microwave of 4 GHz (λ≈7.5 cm) is handled as an example of the 3 to 5 GHz band (λ≈10 to 6 cm) in the electromagnetic wave, the microstrip line at this frequency is used. The dimensions and the like are appropriately designed so that the characteristic impedance of 10 matches the transmitter 19a and the receiver 19b. In the present embodiment, as an example, the dielectric 13 is a relative dielectric constant ε. _r An epoxy containing glass fiber of about 4.7 was used, the width of the strip conductor 12 was 2 to 5 mm, and the distance between the strip conductor 12 and the conductor plate 11 was 1 to 1.5 mm. Of course, these values are the relative dielectric constant ε of the dielectric 13. _r Depending on the value of, the frequency of the microwave used, and the like.
Further, the frequency of the electromagnetic wave to be used is not limited to the above-mentioned 3-5 GHz band microwave, and an appropriate high frequency can be selected as long as the frequency is absorbed by moisture.
[0023]
As shown in FIG. 4A, the shape of the strip conductor 12 in the present embodiment is such that a straight line portion is provided on a diagonal line of the side plate 5R, this straight portion is U-turned, and the input end 12a and the output are formed on one side of the side plate 5R. By positioning the end 12b, the portion below the diagonal line of the side plate 5R is drawn almost over the entire area.
With respect to the routing pattern of the strip conductor 12, it can be routed over almost the entire area along each side of the side plate 5R as shown in FIG. 4B, or at several places as shown in FIG. 4C. Various embodiments can be adopted, such as passing the entire surface of the side plate 5R by folding it back.
[0024]
Further, in the microstrip line 10, the impedance in the non-linear portion of the strip conductor 12 is different from that in the linear portion, so that microwaves are reflected or radiated. In order to avoid these, the non-linear portion of the strip conductor 12 has an acute angle. It is preferable to use an H bent with a blunt angle by cutting away the portion or an H corner with a curve.
[0025]
As shown in FIG. 4, high frequency connectors 14a and 14b such as SMA and BNC are attached to the input end 12a and the output end 12b of the strip conductor 12, respectively, and a transmitter 19a and a receiver are connected by a coaxial cable C or the like. 19b.
[0026]
Here, the measurement principle of the moisture content measuring apparatus 1 of the present invention described above will be described. The strip line includes a symmetric strip line and an asymmetric strip line. The symmetrical strip line can be considered as a modification of the coaxial line, and it can be considered that the coaxial line is transformed into a square waveguide or a rectangular waveguide, and finally its side wall is removed. As shown in FIG. 3B, an electric field (solid line in the figure) is generated from the lower surface of the upper surface of the strip conductor 12 'toward the conductor plate 11' as shown in FIG. A magnetic field (broken line in the figure) around the conductor 12 'is generated.
[0027]
On the other hand, the non-target strip line is structurally formed by removing one of the conductive plates of the symmetric strip line, but is considered to be an electrically deformed parallel two line. That is, as shown in FIG. 3A, an electric field (solid line in the figure) is generated from the lower surface of the strip conductor 12 toward the conductor plate 11, and a magnetic field (broken line in the figure) centered on the strip conductor 12 is generated. Yes. Further, an electric field is generated from the upper edge of the strip conductor 12 toward the conductor plate 11 by the edge effect, and the width of the strip conductor 12 is equivalently increased by the electric field by the edge effect.
The microstrip line 10 used in the present invention is of the non-target type, and is designed as a 3 to 5 GHz band as an example of the transmission frequency.
[0028]
The attenuation of the microwave propagating through the microstrip line 10 as described above becomes a conductor loss, a dielectric loss, and a radiation loss. That is, in the measurement system shown in FIG. 4, the difference between the output value from the transmitter 19a and the input value to the receiver 19b is the sum of the conductor loss, dielectric loss and radiation loss, and the microstrip line 10 When a predetermined level of microwave is transmitted from the transmitter 19a in a state where the sample (tea leaf A) is not positioned above, the microwave attenuated by the amount of the loss arrives at the receiver 19b. The level is the reference value.
[0029]
Then, as shown in FIG. 3A, when the tea leaf A is located facing the strip conductor 12 in the microstrip line 10 with the protective plate 16 interposed, the tea leaf A is exposed from the upper surface edge of the strip conductor 12 to the conductor plate. 11 to block the electric field toward H ₂ When the natural frequency of the electric dipole of O coincides with the frequency of the microwave, a resonance phenomenon of molecules occurs in this portion, the microwave is absorbed, and the microwave is attenuated according to the moisture content of the tea leaf A.
In this respect, the principle of moisture content measurement by microwaves of the present invention is different from the measurement principle of the electric resistance type moisture meter described in the background of the invention.
[0030]
The difference between the level of the microwave transmitted from the transmitter 19a and the level of the microwave arriving at the receiver 19b is the sum of the amount of absorption of the microwave by the tea leaf A as the sample and the amount of attenuation due to the loss. The value obtained by subtracting the attenuation (reference value) due to the loss from the value at this time is the absorption M (dB) of the microwave by the tea leaves A.
And from this value M (dB), the moisture content G (%) of the sample (tea leaf A) can be obtained by the following equation.
G = aM + b (a and b are correction values)
The correction values a and b are values obtained by experiments in advance, and are obtained from the M value obtained by measurement using the measurement system and the weight value of the tea leaves A before and after drying using a weigh scale. It is determined because a correlation can be found between the measured moisture value (measured value).
[0031]
As in the measurement principle described above, the moisture contained in the tea leaf A (tea leaf A located in the space where the electric field is generated) located in the state of being deposited near the upper portion of the strip conductor 12 absorbs microwaves. The tea leaves A located away from the strip conductor 12 do not block the electric field and do not absorb microwaves, so that they are not measured. Therefore, as long as the thickness of the tea leaf A located on the microstrip line 10 is ensured to some extent, the measured value does not change due to the difference in the amount of tea leaf A deposited (sampling amount).
In this part, the moisture content measurement by the microwave of the present invention is different from the measurement principle of the electric resistance type moisture meter described in the background of the invention. That is, in the electrical resistance type, the sample (tea leaf A) located between the electrodes is a part of the circuit, and the moisture content correlated with the resistance value is measured by measuring the resistance value of the sample (tea leaf A). Is measuring. However, since the water drop attached to the surface of tea leaf A actually has a lower resistance value than tea leaf A, a large amount of current flows through the water drop, and the measurement results tend to depend on the water attached to the surface and become inaccurate. It has become difficult to grasp the entire moisture contained in the tea leaves A.
[0032]
The basic embodiment of the moisture content measuring device 1 of the present invention is as described above, and hereinafter, a moisture content measuring method using microwaves using this device and a tea process control method using these will be described.
[0033]
(1) Measurement of reference value
First, in a state where the cylinder 6a is extended and the shutter plate 6 closes the opening 21a, that is, in a state where the tea leaf A is not located in the tea leaf accommodating portion 3, the transmitter is connected to the microstrip line 10 serving as the microwave transmission path. When a microwave is supplied from 19a, a microwave having a level attenuated by the loss inherent in the microstrip line 10 arrives at the receiver 19b, and this reception level is used as a reference value.
[0034]
(2) Sampling
Next, as shown in FIG. 5 (a), when the cylinder 6a is contracted and the shutter plate 6 is retracted, the front surface of the tea leaf housing 3 opens, so It is taken into the accommodating part 3.
[0035]
(3) Pressing of tea leaves
Next, as shown in FIG. 5 (b), the cylinder 6 a is extended and the shutter plate 6 is advanced to close the front surface of the tea leaf housing portion 3, thereby restricting the entry of the tea leaf A into the tea leaf housing portion 3. Then, as shown in the auxiliary projection view of FIG. 5B, the cylinder 5a is extended so that the side plate 5R faces the side plate 5L, and the pressure corresponding to the preset processing state of the tea leaf A (2 kg / cm as an example) ² ), And the tea leaves A sandwiched between the side plates 5R and 5L have a uniform density by eliminating the air between the tea leaves A, and the microstrip line 10 disposed on the side plates 5L. On the other hand, the protective plate 16 is interposed to face closely.
[0036]
(4) Measurement and calculation of moisture content
Then, after an appropriate time has passed, when microwaves are supplied to the microstrip line 10 from the transmitter 19a in this state, the microwaves are absorbed by the moisture contained in the tea leaves A.
For this reason, the level of the microwave transmitted from the transmitter 19a toward the microwave strip line 10 and the level of the microwave received by the receiver 19b do not coincide with each other. The water content of tea leaf A is calculated from the difference between the two.
[0037]
(5) Discharge of tea leaves
Next, as shown in FIG. 5 (c), the cylinder 5a is contracted to move the side plate 5R away from the side plate 5L, and the cylinder 6a is further contracted to retract the shutter plate 6 to open the front surface of the tea leaf storage unit 3. Then, the cylinder 7a is extended and the back plate 7 is advanced to return the tea leaf A located in the tea leaf accommodating portion 3 into the roughing machine 20 from the opening portion 21a.
At this time, since the nylon brush 17 serving as a cleaning mechanism wipes the surface of the protective plate 16, all the tea leaves A located in the tea leaf storage unit 3 can be returned to the roughing machine 20, and the next and subsequent measurements are accurately performed. be able to.
[0038]
(6) Control of tea making process
Next, the moisture content value obtained as described above is processed by a control panel provided in the roughing machine 20 or a control panel for controlling the entire tea production line, and the moisture content is determined as a suitable value in the roughing machine 20. At that point, the processing by the roughing machine 20 is stopped and the tea leaves A are discharged and conveyed to the next process.
[0039]
[Other embodiments]
In the basic embodiment described above, various modifications can be made to the apparatus configuration and measurement method as described below.
[0040]
[Other Embodiments of Microstrip Line Arrangement, etc.]
First, the arrangement of the microstrip line 10 is not limited to one place, but may be arranged on the side plate 5R facing the side plate 5L in addition to the side plate 5L. In this case, the tea leaves A accommodated in the tea leaf accommodating portion 3 can be measured at two locations, that is, the microstrip line 10 provided on the side plate 5L and the microstrip line 10 provided on the side plate 5R. Can be improved.
In addition to the bottom plate 4 as shown in FIG. 6, the microstrip line 10 may be the shutter plate 6, the back plate 7, or the top plate 8 although not shown.
[0041]
In addition, the microstrip line 10 is disposed on the plate frame member because the electric field from the strip conductor 12 toward the conductor plate 13 only needs to pass through the tea leaf housing portion 3. It can also be arranged on the back surface of the side plate 5. In this case, the side plate 5 is made of a material having a relative dielectric constant close to 1, so that the protective plate 16 becomes unnecessary. Further, since the microstrip line 10 is located outside the tea leaf housing part 3, the manufacture and maintenance of the apparatus are simplified.
[0042]
When the strip conductor 12 is protected, instead of providing the protective plate 16, the strip conductor 12 is coated with an insulating resin such as a fluororesin so that the tea leaves A and the like adhere to the strip conductor 12. It can also be prevented. In addition, although the above description demonstrated the case where the moisture content measuring apparatus 1 was comprised integrally with the sampling apparatus 2 which is provided in a tea-making apparatus, it is not restricted to this, About the part which has a common structure, the moisture content measuring apparatus mentioned later The present invention can also be applied to a case where 1 is configured as an independent device.
[0043]
[Other Embodiments with Different Pressing Actions]
In the previous embodiment, the pressing action on the tea leaf A was performed by the side plate 5R, but the point is that the density of the tea leaf A can be kept constant, and can be performed as follows. .
First, a pressing action can be performed by the top plate 8. Specifically, as shown in FIG. 6, a microstrip line 10 is disposed on the surface of the bottom plate 4 on the tea leaf housing part 3 side, and further, A cylinder 8a is connected to a top plate 8 facing the bottom plate 4 to form a pressing action plate.
[0044]
And claims 3 As described above, by providing the airbag 15 on the top plate 8 serving as the pressing action plate, the pressing action can be performed by the airbag 15. 6A, the airbag 15 is formed with a recess on one side of the top plate 8, and an expansion member 15a such as a rubber plate is fixed inside the recess and its peripheral portion is closely fixed. In this way, a chamber is formed, and the expansion member 15a is configured not to protrude from the recess in a contracted state.
[0045]
Here, the measurement using the moisture content measuring apparatus 1 configured as described above will be briefly described. First, similarly to the previous embodiment, after (1) measurement of a reference value and (2) sampling, ( 3) Press the tea leaves. That is, as shown in FIG. 6B, the cylinder 8a is extended to advance the top plate 8 toward the bottom plate 4 to a preset position, and air is supplied to the airbag 15 to inflate the expansion member 15a. The tea leaves A sandwiched between the airbag 15 and the bottom plate 4 eliminate the air between the tea leaves A to make the density uniform, and interpose a protective plate 16 with respect to the microstrip line 10 disposed on the bottom plate 4. And become close. Next, (4) measurement and calculation of water content, (5) discharge of tea leaves.
In addition, although the above description demonstrated the case where the moisture content measuring apparatus 1 was comprised integrally with the sampling apparatus 2 which is provided in a tea-making apparatus, it is not restricted to this, About the part which has a common structure, the moisture content measurement mentioned later is mentioned. The present invention can also be applied to a case where the device 1 is configured as an independent device.
[0046]
[For accuracy improvement instead of pressing action reference Form]
In the previous embodiment, the measurement was performed in a state where the tea leaf A was pressed in order to improve the measurement accuracy. However, depending on the properties of the tea leaf A, the measurement can be performed without requiring the pressing. Specifically, in the case of tea leaves A having a low water content, such as tea leaves A processed by a milling machine, the air between the tea leaves A is eliminated and the density becomes uniform at the stage of sampling without being pressed. , Do not need to press. In this case, the vibration mechanism 18 may be provided to vibrate the tea leaves A so as to positively equalize the density between the tea leaves A. Specifically, as shown in phantom lines in FIGS. 5 and 6, a vibration mechanism 18 is provided on the bottom plate 4 as an example of a plate frame member. As the vibration mechanism 18, as an example, on the rotation shaft of the motor, A known configuration such as a vibration motor having a weight with an eccentric center of gravity or a combination of a crank mechanism and a motor can be employed. By using such a vibration mechanism 18, the tea leaves A are not inadvertently crushed.
In addition, although the above description demonstrated the case where the moisture content measuring apparatus 1 was comprised integrally with the sampling apparatus 2 which is provided in a tea-making apparatus, it is not restricted to this, About the part which has a common structure, the moisture content measurement mentioned later is mentioned. The present invention can also be applied to a case where the device 1 is configured as an independent device.
[0047]
[Other Embodiments of Microwave Transceiver Arrangement]
In the previous embodiment, the transmitter 19a and the receiver 19b are provided at a location distant from the sampling device 2, and these are connected to the microstrip line 12 using the connector 14 and the coaxial cable C. In addition, a receiving device or a voltmeter or the like instead of the receiving device may be directly mounted on the back surface of the plate frame member constituting the tea leaf housing unit 3. In this case, changes in the measurement environment due to the bending of the coaxial cable C can be eliminated, and more accurate measurement can be performed.
In addition, although the above description demonstrated the case where the moisture content measuring apparatus 1 was comprised integrally with the sampling apparatus 2 which is provided in a tea-making apparatus, it is not restricted to this, About the part which has a common structure, the moisture content measurement mentioned later is mentioned. The present invention can also be applied to a case where the device 1 is configured as an independent device.
[0048]
[Other embodiments for different measurement locations]
In the previous embodiment, the microstrip line 10 has one line with respect to the plate frame member, and the measurement was performed on a fixed measurement site for one sample. 5 As shown in FIG. 4, a mechanism that allows the position of the microstrip line 10 to face the tea leaf A can be changed.
Specifically, as an example, by providing a plate frame member including the microstrip line 10 to be rotatable or slidable by an appropriate mechanism, the relative position between the microstrip line 10 and the tea leaves A can be changed, It is possible to continuously perform the measurement with different measurement locations on the same sample.
In addition, even if a plurality of microstrip lines 10 are provided for the plate frame member and the measurements on the individual microstrip lines 10 are sequentially performed sequentially, the measurement can be performed with different measurement locations for the same sample. Can be done continuously.
In addition, although the above description demonstrated the case where the moisture content measuring apparatus 1 was comprised integrally with the sampling apparatus 2 which is provided in a tea-making apparatus, it is not restricted to this, About the part which has a common structure, the moisture content measurement mentioned later is mentioned. The present invention can also be applied to a case where the device 1 is configured as an independent device.
[0049]
[Other Embodiments of Measurement Method]
Next, another embodiment of the measurement method will be described.
[0050]
[Other embodiments of measurement timing]
As for the timing of the measurement, it suffices if the density of the tea leaves A is kept constant. Therefore, the tea leaves A in the tea leaf accommodating portion 3 are pressed by the side plate 5R and the air between the tea leaves A is excluded. After the density is made uniform, the pressing by the side plate 5R or the like may be released, and measurement may be performed at that time.
[0051]
[Other Embodiments of Microwave Used for Measurement]
Moreover, although the microwave used in the previous embodiment was one frequency (4 GHz), as an example, a plurality of measurements were performed using microwaves having a plurality of different frequencies in the 3 to 5 GHz band, and these measured values were measured. It is also possible to take the average of the above, and the measurement accuracy can be improved.
[0052]
[Embodiments used as individual measuring devices]
As described above, the moisture content measuring device 1 of the present invention is configured integrally with the sampling device 2 included in the tea making apparatus, and is configured as a measuring device separate from the sampling device 2 and provided in the tea factory. You can also.
As an example, as shown in FIG. 7 (a), the inside of a cylinder 30 is used as a tea leaf accommodating portion 3, and a bottom plate 4 is provided at the bottom of the cylinder 30, and a piston is slid as the piston sliding inside the cylinder 30. A plate 8 is used. A microstrip line 10 is provided on the upper surface of the bottom plate 4, and a protective plate 16 is covered on the microstrip line 10.
[0053]
Further, as shown in FIG. 7B, the bottom plate 4 is provided with a vibration mechanism 18, the microstrip line 10 is disposed on the bottom plate 4, and the tray D is placed on the microstrip line 10. It can also be. The material of the tray D is preferably a material having a relative dielectric constant close to 1, such as PP or PE.
For such a moisture content measuring device 1, tea leaves A sampled by a belt conveyor or the like are supplied automatically or manually, and tea leaves A are generated during the electric field from the strip conductor 12 to the conductor plate 13. It is possible to measure the moisture content by positioning.
[0054]
【The invention's effect】
According to the present invention, the weight measuring means is not essential as in the conventional apparatus, the cost of the entire apparatus can be reduced, and the measurement accuracy can be improved. An apparatus and a tea process control method using these devices can be provided.
[Brief description of the drawings]
FIG. 1 is a side view showing a state in which a moisture content measuring device of the present invention is attached to a roughing machine.
FIG. 2 is a longitudinal side view and an auxiliary projection view showing a moisture content measuring device of the present invention.
FIG. 3 is a cross-sectional view showing a state of an electric field in a microstrip line and a target strip line.
FIG. 4 is a plan view showing various forms of a microstrip line.
FIG. 5 is an explanatory view showing stepwise a moisture content measurement method using microwaves.
FIG. 6 is an explanatory view showing stepwise another embodiment of a method for measuring moisture content by microwaves.
FIG. 7 is a side view showing a moisture content measuring device configured as an individual measuring device.
[Explanation of symbols]
1 Moisture content measuring device
2 Sampling equipment
3 Tea leaf storage
4 Bottom plate
5 side plate
5a cylinder
5R side plate
5L side plate
6 Shutter plate
6a cylinder
7 Backboard
7a cylinder
8 Top plate
8a cylinder
9 Case
10 Microstrip line
11 Conductor plate
12 Strip conductor
12a input terminal
12b output terminal
13 Dielectric
14 Connector
14a connector
14b connector
15 airbag
15a expansion member
16 Protection plate
17 Nylon brush
18 Vibration mechanism
19a transmitter
19b receiver
20 roughing machine
21 Side plate
21a opening
30 cylinders
A tea leaves
C Coaxial cable
D saucer

Claims (6)

In the apparatus for measuring the moisture content by forming a transmission path composed of a microstrip line between a microwave transmitter and a receiver and positioning the transmission path in a tea leaf accommodating section in a sampling device, the tea leaf accommodating section Is composed of a plate frame member including a bottom plate, a pair of side plates rising on both sides of the bottom plate, a top plate provided to face the bottom plate, and a shutter plate and a back plate rising before and after the bottom plate. The microstrip line is disposed on one or both of the pair of side plates, or one or both of the top plate or the bottom plate, and the back plate can be moved along the side plate and the bottom plate. A plate frame member provided with the microstrip line, or a plate frame member provided with this microstrip line Moisture content measuring device according microwaves, characterized in that the pressing action plate by one or both of the other plate frame member opposed configured to be movable. The micro strip conductor in the strip line, a microwave moisture content measuring apparatus according to the appropriate thickness of the coated claim 1, wherein in the protective plate. The moisture content measuring apparatus using microwaves according to claim 1 or 2, wherein an air bag is provided on the pressing plate. The moisture content measuring apparatus using microwaves according to claim 1, 2 or 3 , further comprising a cleaning mechanism for removing tea leaves, moisture adhering to the microstrip line. 5. The moisture content measuring apparatus using microwaves according to claim 1, 2, 3 or 4 , further comprising a mechanism capable of changing a position where the microstrip line faces the tea leaves. The transmission path between the microwave transmitter and receiver is formed by a microstrip line, and the tea leaves before, after or during processing by the tea making equipment are positioned facing this microstrip line. From the difference in reception level caused by the absorption of microwaves due to moisture contained in the water content, the water content of the tea leaf is calculated, and the extraction time of the tea leaf from the tea making device is determined according to the water content, A tea process control method using the microwave moisture content measuring device according to claim 1, 2, 3, 4 or 5 .

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