JPH0353156Y2 - - Google Patents

Description

[Detailed explanation of the invention] (a) Technical field The present invention relates to a sample moisture measuring device, and more specifically, it combines a measuring device, a heating device, a sample transfer device, etc., and performs control calculations using a microcomputer. , relates to an apparatus for measuring the moisture content of multiple samples.

(b) Prior art Moisture measuring devices that heat and dry a sample placed on a balance with a heat source such as infrared rays, and calculate the moisture content of the sample from the change in weight before and after drying, convert the weight value measured by the balance electronically. One uses an electronic balance that converts it into a signal and displays it digitally, one has a built-in microcomputer in the electronic balance and displays the moisture content digitally, or one uses a microcomputer to control the electronic balance, heating temperature, heating time, etc. There are devices that select the optimal heating conditions according to the sample to be measured and perform more accurate moisture measurements, but they can only measure one sample at a time and require multiple measurements. It cannot be used to measure the moisture content of samples.

On the other hand, there is also a device that heat-dries multiple samples at the same time, manually takes out the samples after drying, and weighs them one by one with an electronic balance to measure the moisture content. It takes a long time to measure because the sample is placed on and removed from the pan manually, and weighing errors due to hot air flow during weighing are added, which not only causes a decrease in measurement accuracy, but also causes the sample to be dry. If this has not been reached, there are problems such as the need to repeat heating, drying, and weighing, and it is not possible to measure the moisture content of multiple samples simultaneously or continuously.

(c) Point of focus The inventors of the present invention have conducted intensive studies to resolve the above-mentioned problems and to develop a device that can continuously and automatically measure the moisture content of multiple samples.
By combining a weighing device, heating device, sample transfer device, etc., and controlling and calculating using a microcomputer, it is possible to efficiently measure multiple samples and prevent weighing errors caused by hot air flow during weighing, resulting in high accuracy. They found a device that can automatically measure moisture and came up with the present invention.

(d) Purpose of the invention The first purpose of the invention is to provide a new device for effectively measuring moisture in various samples.
The second purpose of the present invention is to provide a new moisture measuring device that can measure the moisture content of multiple samples simultaneously or continuously with high efficiency and with high accuracy while preventing weighing errors caused by hot air flow during weighing. It is in.

Further objects of the present invention will become apparent from the following description.

(e) Structure of the invention The purpose of the invention is to measure the moisture content of samples placed in multiple sample dishes by heating them from the top of the sample dishes to evaporate the water in the samples and measure the moisture content. A heating device, a sample plate whose weight may be different between multiple pieces, and a weighing device that converts the weight of the sample before and after drying into an electrical signal, whose weight may be different between multiple pieces. and a windshield that prevents weighing errors due to hot air flow during measurement, which is comprised of a seal tube and a windproof cover provided surrounding the weighing device and the sample dish, and a shielding plate provided on the top of the sample dish when being weighed. The device is equipped with a transfer device on which a plurality of the sample dishes are placed, and an elevating device for moving the transfer device up and down, and is capable of setting the transfer device in a fixed position, blinking and adjusting the intensity of the heat source of the heating device. , control to place the sample plate on the weighing device by lowering the transfer device, memorizing the measured value and checking the absolute dry state, calculating the moisture content, and releasing the sample plate from the weighing device by raising the transfer device. This is achieved by a moisture measuring device equipped with a calculation mechanism.

(f) Specific explanation of the configuration According to the device of the present invention, sample plates (the weights of which may be different among multiple pieces) are prepared based on the measurement method inputted in advance into the microcomputer. starting, stopping, and moving the transfer device up and down, weighing the sample (the weight of which may vary among multiple samples), blinking the heat source of the heating device and adjusting the intensity of heating, and storing the measured values. Confirmation of absolute dryness, calculation of moisture content, etc. are automatically performed, so the measurer only needs to insert and remove samples, and the moisture content of multiple samples can be measured in a short time and by hot air flow during weighing. Errors can also be prevented and the process can be performed with high precision.

In addition, by removing only the sample from the sample dish on which moisture measurement has been completed and inserting another sample, it is possible to successively measure a large number of samples one after another.

Next, one embodiment of the device of the present invention will be described in detail based on the drawings.

FIG. 1 shows an outline of the apparatus of the present invention, in which a plurality of sample dishes 3 containing samples 2 are placed on a rotary table 1 serving as a transfer device.

Although the rotary table 1 is shown as an example of a transfer device, it may be of any type as long as it can place and transfer a plurality of sample plates on a flat surface; for example, a rotating conveyor may be used. A sample plate 3 is placed on the rotary table 1 concentrically, and a plurality of notched holes are provided so that the sample plate 3 can be placed directly on the weighing platform 5 of the electronic balance 4 as a weighing device during measurement. There is. Therefore, except when weighing with the electronic balance, the sample dish 3 is placed in the notched hole on the rotary table, and during weighing, the sample dish located directly above the electronic balance is placed on the rotary table 1.
It has become easier to separate from the

The material of the sample plate 3 is preferably light and made of metal such as stainless steel or aluminum because it is exposed to high temperatures together with the sample 2 by a heating device and is used for weight measurement. The sample plate may be in any shape as long as it can be placed on the rotary table 1 and the weighing platform 5 of the electronic balance. A mesh plate may be used to reduce the weight of the plate itself.

The material of the rotary table 1 may be either metal or plastic, which does not undergo thermal deformation.

The rotary table 1 has a gear 6 on its central axis for rotating the rotary table and a rack-and-pinion mechanism 7 as a lifting device for moving the rotary table up and down, and the gear 6 is connected to an 8-shaft motor with a brake that is a driving source. It meshes with a gear 9 fixedly attached to the. Here, in the embodiment of the present invention, a case where the rotary table 1 is rotated via a gear is illustrated, but a chain, a belt, etc. are similarly adopted instead of a gear on the rotating shaft of the motor 8 with a brake as a mechanism for rotating the rotary table. Needless to say, it is possible to do so.

A motor 8 with a brake for rotating the rotary table once is started or stopped by an electric signal from a control arithmetic unit 10 of a microcomputer.

On the other hand, the detection ends of a plurality of position sensors are attached to the center circumference of the back surface of the rotary table 1, and in response to the position sensors 11, electric signals are sent to the control calculation device 10 to control the operation of the motor 8 with a brake. , commands the rotary table 1 to stop at a specified position.

The rack and pinion mechanism 7 is combined with a motor 12 with a brake, and rotates the pinion in response to an electric signal from a control/arithmetic unit 10. The pinion meshes with a rack having the gear 6 fixedly attached to the upper end thereof, and since the gear 6 is fixedly attached to the rotary table 1, the rotary table 1 moves up and down by the rotation of the pinion.

In this embodiment, a rack-and-pinion mechanism is used as an example of a device for moving the rotary table up and down, but any mechanism that moves the rotary table up and down a certain distance can be used, such as a hydraulic mechanism, a pneumatic mechanism, a screw mechanism, etc. can also be adopted.

Furthermore, in this example, an elevating device was installed to raise and lower the rotary table, but if the elevating device is attached to an electronic balance, which is a weighing device, without moving the rotary table up and down, the sample plate can be moved electronically by raising the electronic balance. The sample dish can be placed on the weighing platform of a balance, and when the electronic balance is lowered, the sample dish can be separated from the weighing platform and placed on a rotary table.

In order to control the vertical movement distance of the rotary table 1, a detection end of a position sensor 13 is provided at the lower end of the rack, and in response to the position sensor 13, an electric signal is transmitted to the control calculation device 10.

In order to weigh a plurality of sample plates (the weights of which may be different among the plurality of sample plates) placed on the rotary table 1, a certain gap is provided directly below the sample plates to serve as a weighing device. One electronic balance 4 is installed. The electronic balance 4 sends the weight value of the object to be weighed to the control calculation device 10 by an electric signal, and displays necessary information on the digital display device 15 according to a program input in advance from the input device 14 of the microcomputer. display or printer 16
It is also possible to record the

The weighing platform 5 of the electronic balance 4 is positioned below the rotary table 1 with a gap while the rotary table 1 is rotating, and during weighing, the rotary table stops rotating and is rotated by lowering the rotary table using an elevating device. The sample plate 3 placed on the table 1 is separated from the rotary table 1 and placed on the weighing table 5.

In order to prevent weighing errors caused by air currents during weighing, a seal cylinder 17 is attached to the electronic balance 4 so as to eliminate a gap with the rotary table 1, and the diameter and height of the sample plate mounting portion of the rotary table 1 are similar to that of the sample plate. It is essential to securely install a larger cylindrical windbreak cover 18.

On the other hand, a shielding plate 19 is used to shield the sample plate to be weighed from the heated atmosphere and prevent the influence of hot air current.
It is essential to securely install the shielding plate, but the lower end of the shielding plate is
The upper end may have a cylindrical shape or a rectangular cylindrical shape with the same height as the ceiling of the main device, and the ceiling may be open. The shielding plate may be made of either metal or plastic, and in particular, in order to improve heat insulation, it is preferable to have a mirror-finished outer surface or a double structure with a heat insulating material inside.

An infrared lamp 20 is provided as a heating device directly above the sample dish 3, and a microcomputer control arithmetic unit 1 receives an electrical signal from a temperature sensor 21 installed in the middle between the sample dish 3 and the infrared lamp 20.
The intensity of heating of the infrared lamp 20 is controlled by the voltage regulator 24 based on the command 0. Although a hemispherical infrared lamp is used as an example of the infrared lamp in this embodiment, any type of infrared lamp may be used as long as the heating and drying effect can be obtained, such as an infrared tube type heater or a ceramic heater. The drying efficiency can be increased by providing the same number of infrared lamps 20 as the other sample plates except for the one directly above the electronic balance, but it is also possible to install at least one infrared lamp 20.

The drying chamber 22 of this apparatus is surrounded by a drying box 23, which reduces the intrusion of outside air and prevents heat radiation. Electronic balance 4 of the drying box 23
An opening/closing window is provided on the side of the installation section for tasks such as loading and unloading samples.

On the other hand, in order to prevent moisture evaporated from the sample from remaining in the drying chamber as the drying progresses, the top plate of the drying box is open or has a perforated plate, and the bottom end of the drying box is placed on the back side of the rotary table 1. It is preferable to bend it with a gap so that it does not come in contact with the drying chamber, and an appropriate amount of outside air is sucked in through this gap along with the convection of the air inside the drying chamber.

The electronic balance 4, motors with brakes 8, 12, etc. are placed in the drying box 2 to avoid the heated atmosphere during drying.
It is located outside of 3.

An example of the moisture measuring operation of the apparatus of the present invention having the above-mentioned configuration will be explained in more detail.

A total of 8 sample dishes 3 are placed in the 8 cutout holes of the rotary table 1, and the rotary table 1 is rotated by driving the motor 8 with a brake. Dry. In this case, the irradiation time and irradiation temperature of the infrared lamp 20 are adjusted in accordance with the moisture measurement prescription inputted in advance from the input device 14 of the microcomputer. When the sample plate 3 reaches an absolutely dry state, the rotation of the rotary table 1 is stopped by the motor 8 with a brake, and the rotary table 1 is stopped at an appropriate position by the position sensor 11. Next, the motor 12 with a brake is started, the rack and pinion mechanism 7 is activated, and the rotary table 1 is lowered and stopped at an appropriate position by the position sensor 13. At this point, the first sample plate 3 is placed on the weighing platform 5 of the electronic balance 4, and the weight (tare) of the sample plate is measured.
It is stored in the control arithmetic unit 10 of the microcomputer. Next, an appropriate amount of the sample 2 (the weight of which may be different among the plurality of samples) is placed in the sample dish, weighed using the electronic balance 4, and stored in the control/arithmetic unit 10.

When the first measurement is completed, the motor 12 with a brake is started, and the rack and pinion mechanism 7 is activated to raise the rotary table 1. When the rotary table 1 rises to the proper position, the motor with brake 12 stops, and then the motor with brake 8 starts to rotate the rotary table 1 by 1/8 turn. At this time, the first sample is located directly under the infrared lamp 20, and heating and drying of the sample has begun. In addition, a second sample pan 3 is placed on the rotary table 1 and stopped directly above the electronic balance 4, and the rotary table is lowered, the sample pan (tare) is weighed, the sample is loaded, and the sample is weighed. , raising and rotating the rotary table, etc., according to the steps previously described. Input the 3rd, 4th, 8th sample in the same way.
It is weighed and drying is in progress.

When samples are placed in all eight sample dishes, based on the measurement method inputted in advance from the input device 14, the rotary table 1 is stopped and lowered for each sample dish, and the dry sample is weighed by the electronic balance 4.
The operation of raising and rotating the rotary table is repeated. All measured values are stored in the control calculation device 10,
When the difference between the two measurements of the same sample is within the allowable range, the dry state is confirmed.
The moisture content is calculated and the sample number and moisture content are displayed on the digital display device 15. The sample that has reached an absolutely dry state and whose moisture content has been measured is removed from the sample pan, and then the next sample is added and the above steps are repeated to obtain the 9th, 10th...nth sample. The moisture content can be measured.

Incidentally, after the samples 2 are placed in all the sample dishes 3, the rotary table 1 may be stopped or rotated continuously for a certain period of time under irradiation with the infrared lamp 20, and then each sample may be weighed.

In addition, in the above example, it is stated that the sample pan 3 is weighed each time it is used, but the weight of all the sample pans should be calculated in advance, and after the samples are put in at the time of moisture measurement, they are placed on the rotary table 1 one after another and the sample weight is measured. I don't mind if you do.

In addition, measurement and calculation by the electronic balance 4, blinking of the infrared lamp 20 and adjustment of heating strength, detection of heating temperature, rotation or stopping of the rotary table by starting or stopping the motor 8 with a brake, and starting or stopping the motor 12 with a brake. The up and down movement of the rotary table or its stopping, the detection of the appropriate position of the rotary table by the position sensors 11 and 13, etc. respond and operate according to the moisture measurement program inputted in advance to the control arithmetic unit 10 of the microcomputer. .

Furthermore, the sample number, moisture content, etc. can be displayed on the digital display device 15 or recorded on the printer 16.

(g) Effects of the invention According to the device of the invention, a separate drying test is performed on any sample to determine the optimum drying conditions, and the drying conditions (heating temperature, , time, etc.) may be modified as appropriate. Furthermore, it can be used not only for evaporating water in a sample, but also for evaporating and drying volatile liquids or organic liquids having a low boiling point or a boiling point close to the boiling point of water.

The device of this invention can efficiently measure moisture especially when there are a large number of samples.
Continuous measurements can be performed under the same conditions except for taking out the moisture by hand, making it possible to shorten measurement time and improve measurement accuracy compared to conventional moisture measurement devices. In particular, measurement accuracy may be reduced due to insufficient drying or denaturation due to burning of the sample due to overheating due to the use of a microcomputer to confirm the absolute dry state of the sample, and weighing errors caused by hot air flow during weighing. It doesn't cause any problems.

Naturally, it is not necessary to create all sample dishes with the same weight, and it is not necessary to create all samples with the same weight, so the equipment is easy to create and maintain, and measurement efficiency is improved. Significant improvement.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram showing one embodiment of the device of the present invention, and FIGS. 2 to 5 show functional control diagrams using a control calculation device of a microcomputer. Specifically, FIG. 2 shows the heating device section, FIG. 3 shows the transfer device section, FIG. 4 shows the lifting device section, and FIG. 5 shows the measuring device section. 1... Rotary table, 2... Sample, 3... Sample plate, 4... Electronic balance, 5... Weighing stand, 6... Gear, 7... Rack and pinion mechanism, 8... Motor with brake, 9 ... Gear, 10 ... Control calculation device, 11 ... Position sensor, 12 ... Motor with brake, 13 ... Position sensor, 14 ... Input device, 15 ... Digital display device, 16 ... Printer, 17 ... ... Seal cylinder, 18 ... Windproof cover, 19 ... Shielding plate, 20 ... Infrared lamp, 2
1...Temperature sensor, 22...Drying room, 23...
Drying box, 24...voltage regulator.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In a moisture measuring device that measures the moisture content by heating samples placed in a plurality of sample trays from the top of the sample trays to evaporate the moisture in the samples, , a sample plate whose weight may be different among a plurality of pieces; a weighing device which converts the weight of the sample before and after drying into an electric signal, whose weight may be different between a plurality of pieces; A windshield device that prevents weighing errors due to hot airflow during measurement, which includes a seal tube and a windbreak cover provided surrounding the weighing device and the sample dish, and a shielding plate provided on the top of the sample dish when being weighed; It is equipped with a transfer device on which a plurality of the sample dishes are placed, and an elevating device for moving the transfer device up and down, and includes a method for setting the transfer device in a fixed position, blinking and adjusting the intensity of the heat source of the heating device, and the transfer device. A control and calculation mechanism is provided for placing the sample plate on the weighing device by lowering the transfer device, memorizing the measured value, checking the absolute dry state, calculating the moisture content, and releasing the sample plate from the weighing device by raising the transfer device. A moisture measuring device characterized by: (2) The moisture measuring device according to claim 1, wherein the measuring device is an electronic balance. (3) The moisture measuring device according to claim 1, wherein the transfer device is a rotary table. (4) The moisture measuring device according to claim 1, wherein the heating device is an infrared lamp.