Moisture content measuring device

Abstract

To provide a moisture content measuring device that can prevent a conduction failure caused by rust between a crushing roller and an electrode terminal.SOLUTION: When grain which is the harvest is being crushed between circumferential surfaces of crushing rollers 17, 18, a signal corresponding to an electrical resistance value between the electrode terminals 45, 46 is output from a measurement circuit. Roller electrodes 32, 35 are attached in a replaceable manner to a front end surface 27 of a roller shaft 25 of the crushing roller 17 and a front end surface 28 of the roller shaft 26 of the crushing roller 18, respectively. With this, when rust is generated in a localized area where the roller electrode 32 and the electrode terminal 45 come into contact with each other and / or a localized area where the roller electrode 35 and the electrode terminal 46 come into contact with each other, the roller electrodes 32, 35 can be replaced with the roller electrodes 32, 35 in which rust is not generated, for example, new roller electrodes 32, 35.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a moisture content measuring device mounted on a harvesting machine such as a combine, which measures the moisture content of the harvested product harvested by the harvesting machine.

Background Art

[0002] For example, a combine is a harvesting machine that harvests grains such as rice and wheat. In a combine, the crops standing in the field are cut by a cutting device, and the cut crops are conveyed from the cutting device to a threshing device, and the grains are removed from the crop straw by the threshing device. The grains separated from the straw are conveyed from the threshing device to a discharge portion provided at the upper part in the grain tank, and are discharged from the discharge portion into the grain tank and collected.

[0003] Some combines are equipped with an electric resistance type moisture content measuring device (moisture meter) in the grain tank to measure the moisture content of the grains. The moisture content measuring device is arranged at a position where it can receive the grains discharged from the discharge portion. The moisture content measuring device is provided with a pair of crushing rollers, and electrode terminals for measuring the electric resistance value between the electrode rollers are provided in contact with the shafts of the respective crushing rollers. The grains received in the moisture content measuring device are卷入between the circumferential surfaces of the crushing rollers by the rotation of the crushing rollers and crushed between the circumferential surfaces of the crushing rollers. With the crushed product of the grains sandwiched between the circumferential surfaces of the crushing rollers, the electric resistance value between the crushing rollers is measured, and the moisture content of the grains is determined from the electric resistance value (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, it was found that conventional moisture content measuring devices develop rust in the localized area where the crushing roller shaft and the electrode terminals come into contact. When this rust occurs, poor conductivity occurs between the crushing roller and the electrode terminals, making it impossible to accurately measure the electrical resistance between the crushing rollers.

[0006] The objective of the present invention is to provide a moisture content measuring device that can prevent poor electrical conductivity caused by rust between the crushing roller and the electrode terminal. [Means for solving the problem]

[0007] To achieve the above objective, the moisture content measuring device according to the present invention is a moisture content measuring device mounted on a harvesting machine for measuring the moisture content of harvested produce harvested by the harvesting machine, and includes a pair of crushing rollers whose circumferential surfaces are arranged in close proximity to each other and which crush the harvested produce between their circumferential surfaces by rotation, roller electrodes which are interchangeably attached to one end face of each of the crushing rollers, electrode terminals which contact each of the roller electrodes, and a measuring circuit which outputs a signal corresponding to the electrical resistance value between one electrode terminal and the other electrode terminal when the harvested produce is being crushed between the circumferential surface of one crushing roller and the circumferential surface of the other crushing roller.

[0008] In this configuration, when harvested produce is being crushed between the circumferential surface of one crushing roller and the circumferential surface of the other crushing roller, the measurement circuit outputs a signal corresponding to the electrical resistance value between the electrode terminals of one and the other. A roller electrode is removably attached to one end face of each crushing roller. This allows the roller electrode to be replaced with a new one (a roller electrode that has not rusted) if rust occurs in the area where the roller electrode and the electrode terminal come into contact. By replacing the roller electrode with a new one, poor conductivity due to rust between the crushing roller and the electrode terminal can be prevented, and the electrical resistance value between one crushing roller and the other can be measured accurately. Consequently, the moisture content of the harvested produce being crushed between one crushing roller and the other can be measured accurately.

[0009] In conventional moisture content measuring devices, the electrode terminals are in contact with the shaft of the crushing roller. Therefore, if rust occurs in the area where the crushing roller shaft and the electrode terminals are in contact, the crushing roller must be replaced with a new one, which is time-consuming and costly. In contrast, in the moisture content measuring device according to the present invention, if rust occurs in the area where the roller electrode and the electrode terminal are in contact, only the roller electrode needs to be replaced. Compared to conventional moisture content measuring devices, this reduces the time and cost of replacement.

[0010] Furthermore, the problem of rust formation is particularly pronounced in moisture content measuring devices installed in harvesters, but less likely to occur in moisture content measuring devices installed in dryers. Comparing harvesters and dryers, the humidity inside the tank where harvested material is stored is high in harvesters, while the temperature inside the room where the material to be dried is stored is low in dryers. Therefore, the problem that the present invention aims to solve is a problem that is not present in moisture content measuring devices installed in dryers, and the present invention cannot be easily conceived based on the configuration of moisture content measuring devices installed in dryers.

[0011] The moisture content measuring device further includes a case for housing a crushing roller, and electrode terminals may be interchangeably mounted on the case.

[0012] In this configuration, if rust occurs at the point where the roller electrode and electrode terminal come into contact, the electrode terminal can be replaced with a new one (an electrode terminal that is not rusted). By replacing the electrode terminal with a new one, poor conductivity due to rust between the crushing roller and the electrode terminal can be prevented, and the electrical resistance between one crushing roller and the other can be measured with greater accuracy. Consequently, the moisture content of the harvested material being crushed between the two crushing rollers can be measured with greater accuracy.

[0013] The roller electrode may be exposed from the case, and the electrode terminal may be configured to contact the roller electrode outside the case.

[0014] This configuration allows the user of the harvesting machine to visually check for rust in the localized area where the roller electrode and electrode terminal come into contact.

[0015] The moisture content measuring device further includes a spacer interposed between one end face of the crushing roller and the roller electrode, and preferably the roller electrode is suspended from the case.

[0016] This configuration prevents the roller electrodes from rubbing against the case when the crushing roller rotates.

[0017] The moisture content measuring device further includes a terminal holding member fixed to the case, and the electrode terminals may be held by the terminal holding member and extend from the terminal holding member.

[0018] In this configuration, the electrode terminals extend in a direction intersecting the rotation axis of the crushing roller, and the tip may bend in a direction approaching the roller electrode midway, and the tip may be in contact with the roller electrode.

[0019] The bending of the electrode terminal increases the contact pressure between the tip of the electrode terminal and the roller electrode. As a result, rust formation at the local contact point between the roller electrode and the electrode terminal can be prevented, and even if rust does occur, the rotation of the crushing roller (roller electrode) can scrape off the rust with the electrode terminal. Therefore, poor conductivity due to rust between the crushing roller and the electrode terminal can be prevented.

[0020] The moisture content measuring device may further include a mounting base to which a terminal holding member is attached and which is attached to a case.

[0021] Furthermore, the electrode terminals are in contact with the roller electrodes at a position offset in a predetermined direction from the rotation axis of the crushing roller, the mounting base has a pair of walls facing each other in a predetermined direction, and the terminal holding member may be positioned between the pair of walls.

[0022] If the electrode terminal contacts the roller electrode at a position offset in a predetermined direction with respect to the rotation axis of the crushing roller, when the crushing roller rotates, the electrode terminal may sway in the predetermined direction, and the contact state between the electrode terminal and the roller electrode may become unstable. By arranging the terminal holding member between a pair of wall surfaces of the mounting base, the movement of the terminal holding member in a predetermined direction is restricted, so that it is possible to suppress the sway of the electrode terminal in the predetermined direction when the crushing roller rotates.

[0023] By attaching the terminal holding member to a single mounting base, the electrode terminal, the terminal holding member, and the mounting base may be integrated.

[0024] With this configuration, the one and the other electrode terminals and the terminal holding member that holds them can be removed from the case together with the mounting base and replaced with new ones.

[0025] When the crushing roller is made of a metal different from that of the electrode terminal, it is preferable that at least the portion of the roller electrode that contacts the electrode terminal is made of the same metal as the electrode terminal.

[0026] Thereby, it is possible to prevent the occurrence of dissimilar metal contact corrosion (galvanic corrosion) at the local portion where the roller electrode and the electrode terminal contact each other.

[0027] The roller electrode is fixed to the crushing roller by a fixing screw, and a configuration in which the fixing screw is made of a metal different from that of the roller electrode may be adopted.

[0028] Furthermore, a configuration may be adopted in which the crushing roller is made of iron, the roller electrode and the electrode terminal are made of copper, and the fixing screw is made of stainless steel.

[0029] Since copper and stainless steel have similar natural potentials (ionization tendencies), using stainless steel fixing screws when the roller electrodes are made of copper can suppress galvanic corrosion at the point where the roller electrodes and fixing screws come into contact. As a result, rust caused by galvanic corrosion on the roller electrodes can be suppressed, and poor conductivity due to rust between the crushing roller and the electrode terminals can be further prevented. [Effects of the Invention]

[0030] According to the present invention, poor conductivity due to rust between the crushing roller and the electrode terminal can be prevented. Therefore, the electrical resistance between one crushing roller and the other can be measured with high accuracy, and consequently, the moisture content of the harvested material being crushed between the two crushing rollers can be measured with high accuracy. [Brief explanation of the drawing]

[0031] [Figure 1] This is a right side view of a combine harvester equipped with a moisture content measuring device according to one embodiment of the present invention. [Figure 2] This is a perspective view of a moisture content measuring device. [Figure 3] This is a view of the moisture content measuring device from the front. [Figure 4] This is a perspective view of the front lower part of the roller unit, seen from the front and below. [Figure 5] This diagram illustrates the circuit configuration of a moisture content measuring device. [Figure 6] This block diagram shows the key components of the electrical system of a combine harvester. [Figure 7] This flowchart shows the flow of the anomaly detection process. [Figure 8] This is a side view of an electrode terminal according to a modified example. [Figure 9] This is a view of the mounting base according to a modified example, seen from the front. [Modes for carrying out the invention]

[0032] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0033] <Overall configuration of a combine harvester> Figure 1 is a right side view of a combine harvester 1 equipped with a moisture content measuring device according to one embodiment of the present invention.

[0034] A combine harvester is an agricultural machine that cuts and threshes crops while traveling through a field, and is a harvesting machine that collects grain.

[0035] Combine harvester 1 employs a pair of crawler tracks 2 on the left and right sides as a running device capable of traversing uneven terrain such as fields. The machine frame 3 is supported by the left and right crawler tracks 2, and power from the engine mounted on the machine frame 3 is transmitted to the crawler tracks 2 via a transmission.

[0036] Furthermore, a cabin 4, a threshing device 5, and a grain tank 6 are mounted on the machine frame 3. A harvesting device 7 for cutting crops is mounted in front of the crawler track 2 and the machine frame 3.

[0037] Cabin 4 is located on the front end of the aircraft frame 3. Cabin 4 provides a space for the user to board, and within this space are, for example, a cockpit where the user sits and control levers that the user operates. A retractable door 8 is provided on the right side of Cabin 4, and the user can open the door 8 and enter Cabin 4.

[0038] The threshing device 5 is located to the left rear of the cabin 4. The grain tank 6 is located behind the cabin 4 and to the right of the threshing device 5. In the threshing device 5, the sorting material obtained by threshing the crop is sorted and collected. The collected sorting material (grain) is transported to the grain tank 6 and stored in the grain tank 6. An unloader 9 is connected to the grain tank 6, and the grain stored in the grain tank 6 can be discharged from the grain tank 6 to the outside of the machine by the unloader 9.

[0039] <Moisture content measuring device> Figure 2 is a perspective view of the moisture content measuring device 11.

[0040] The grain tank 6 is equipped with a moisture content measuring device 11 for measuring the moisture content of the grain stored in the grain tank 6. Although not shown in the figures, the grain tank 6 is also equipped with a discharge section for discharging the grain transported from the threshing device 5. The discharge section is equipped with rotating blades that rotate around an axis extending in the vertical direction, and the grain transported to the discharge section is swept away by the rotating blades. The moisture content measuring device 11 is positioned in a location that can receive the grain discharged from the discharge section, for example, on the front inner wall surface of the grain tank 6.

[0041] In the following, assuming that the moisture content measuring device 11 is located on the front inner wall surface of the grain tank 6, the front-to-back, left-to-right, and up-and-down directions of the moisture content measuring device 11 are the same as the front-to-back, left-to-right, and up-and-down directions of the combine harvester 1.

[0042] The moisture content measuring device 11 is equipped with a box-shaped housing 12. A roller unit 13 is provided inside the housing 12, and an opening 14 is formed on the rear surface of the housing 12 to expose the rear surface of the roller unit 13.

[0043] The roller unit 13 includes a rear case 15 with an open front. An inlet 16 is formed on the rear surface of the rear case 15 for receiving grain into the rear case 15.

[0044] A pair of crushing rollers 17 and 18 are housed inside the rear case 15. The crushing rollers 17 and 18 are arranged side by side behind the receiving inlet 16, with their rotation axes extending in the front-to-back direction. There is a gap between the circumferential surfaces of the crushing rollers 17 and 18 that corresponds to the size of the rice (paddy rice), and is slightly smaller than the width of the rice (length in the direction perpendicular to the longitudinal direction). Numerous minute irregularities are formed on the circumferential surfaces of the crushing rollers 17 and 18. Powered by the motor 66 (see Figure 6), the left crushing roller 17 rotates clockwise, and the right crushing roller 18 rotates counterclockwise.

[0045] Some of the grain scattered from the discharge port in the grain tank 6 reaches the housing 12 and is directly received into the housing 12 through the receiving port 16. In addition, a guide member 19 is attached to the rear surface of the housing 12, and grain that reaches the guide member 19 flows over it, falls from the guide member 19, and is received into the rear case 15 through the receiving port 16. The grain received into the rear case 15 through the receiving port 16 accumulates on the circumferential surfaces of the crushing rollers 17 and 18. When the crushing rollers 17 and 18 rotate, the grain is crushed as it is squeezed between the circumferential surfaces of the crushing rollers 17 and 18.

[0046] Figure 3 is a view of the moisture content measuring device 11 from the front.

[0047] The roller unit 13 includes a plate-shaped front case 21. The front case 21 is provided to close the front of the rear case 15, and the rear case 15 and the front case 21 together provide a roller housing space for housing the crushing rollers 17 and 18.

[0048] Figure 4 is a perspective view of the front lower part of the roller unit 13, seen from the front and below.

[0049] The front case 21 has circular openings 22 and 23 formed on the axes of the crushing rollers 17 and 18, respectively. The crushing rollers 17 and 18 each have an integral roller shaft 25 and 26. The front end surface 27 of the roller shaft 25 and the front end surface 28 of the roller shaft 26 (see Figure 8) are exposed forward through the openings 22 and 23, respectively.

[0050] A ring-shaped roller electrode 32 and a spacer 33 are interchangeably attached to the front end surface 27 of the roller shaft 25 by a fixing screw 31. Specifically, the fixing screw 31 is inserted from the roller electrode 32 side into the center of the roller electrode 32 and spacer 33, which are stacked on top of each other. A screw hole is formed in the center of the front end surface 27 of the roller shaft 25, and the tip of the fixing screw 31, which is inserted through the roller electrode 32 and spacer 33, is screwed into this screw hole. In this way, the roller electrode 32 and spacer 33 are fixed to the roller shaft 25 with the spacer 33 interposed between the front end surface 27 of the roller shaft 25 and the roller electrode 32. Because the spacer 33 is interposed between the front end surface 27 of the roller shaft 25 and the roller electrode 32, the roller electrode 32 is provided in a state of floating from the front case 21 and is not in contact with the front case 21. When the fixing screw 31 is removed, the fixing of the roller electrode 32 and spacer 33 to the roller shaft 25 is released. Therefore, by removing the fixing screw 31, the roller electrode 32 and spacer 33 can be removed from the roller shaft 25. Then, the fixing screw 31 can be used to attach another roller electrode 32 and spacer 33 to the front end face 27 of the roller shaft 25.

[0051] An annular plate-shaped roller electrode 35 and a spacer 36 are removably attached to the front end surface 27 of the roller shaft 26 by fixing screws 34. The mounting configuration of the roller electrode 35 and spacer 36 is the same as that of the roller electrode 32 and spacer 33, so a detailed explanation is omitted.

[0052] A terminal unit 41 is attached to the front case 21. The terminal unit 41 comprises a mounting base 42, terminal holding members 43 and 44 attached to the mounting base 42, and electrode terminals 45 and 46 held by the terminal holding members 43 and 44, respectively.

[0053] The mounting base 42 is roughly rectangular in shape. The mounting base 42 is positioned on the front surface of the front case 21, below the roller electrodes 32 and 35, and extends longer in the left-right direction than in the up-down direction. The mounting base 42 is attached to the front case 21 by, for example, two fixing screws 37.

[0054] The terminal holding members 43 and 44 are positioned on the front surface of the mounting base 42, each offset to the left with respect to the center of the roller electrodes 32 and 35. The terminal holding members 43 and 44 have the same configuration, and each of the terminal holding members 43 and 44 is equipped with a front holding plate 47 and a rear holding plate 48 that are stacked on top of each other.

[0055] Electrode terminals 45 and 46 have the same configuration. Here, we will explain the configuration of electrode terminal 45, and omit the explanation of the configuration of electrode terminal 46. In Figures 3 and 4, the parts of electrode terminal 46 that correspond to the parts of electrode terminal 45 are given the same reference numerals as the parts of electrode terminal 45.

[0056] The base end 51 of the electrode terminal 45 is roughly rectangular in shape. The electrode terminal 45 has two terminal arms 52 and 53 that extend from the base end 51 in the longitudinal direction of the base end 51. On one side of the tip of each terminal arm 52 and 53, roughly semicircular terminal contacts 54 and 55 are provided protruding.

[0057] The electrode terminal 45 is positioned such that its base end 51 is sandwiched between the front retaining plate 47 and the rear retaining plate 48 of the terminal retaining member 43, and the terminal contacts 54 and 55 contact the roller electrode 32 at a position shifted to the left with respect to the center of the roller electrode 32 (the rotation axis of the crushing roller 17). The front retaining plate 47 and the rear retaining plate 48 are then attached to the mounting base 42 in an integrated state by fixing screws 56 that penetrate the terminal retaining member 43 in the front-to-back direction, and the base end 51 of the electrode terminal 45 is sandwiched between the front retaining plate 47 and the rear retaining plate 48.

[0058] The electrode terminal 46 is positioned such that its base end 51 is sandwiched between the front retaining plate 47 and the rear retaining plate 48 of the terminal retaining member 44, and the terminal contacts 54 and 55 contact the roller electrode 35 at a position shifted to the left with respect to the center of the roller electrode 35 (the rotation axis of the crushing roller 18). The front retaining plate 47 and the rear retaining plate 48 are then attached to the mounting base 42 in an integrated state by fixing screws 57 that pass through the terminal retaining member 43 in the front-rear direction, and the base end 51 of the electrode terminal 46 is sandwiched between the front retaining plate 47 and the rear retaining plate 48.

[0059] The roller electrodes 32, 35 and electrode terminals 45, 46 are made of the same type of metal, while the crushing rollers 17, 18 are made of a different type of metal than the roller electrodes 32, 35 and electrode terminals 45, 46. The materials of the spacers 33, 36 and fixing screws 31, 34 may be the same type of metal as the roller electrodes 32, 35 and electrode terminals 45, 46, or they may be a different type of metal. Furthermore, the materials of the spacers 33, 36 and fixing screws 31, 34 may be the same type of metal as the crushing rollers 17, 18, or they may be a different type of metal. However, since the spacers 33, 36 and fixing screws 31, 34 come into contact with the roller electrodes 32, 35, it is preferable that they be made of materials with a similar natural potential (ionization tendency) to the materials of the roller electrodes 32, 35 and electrode terminals 45, 46 in order to suppress the occurrence of galvanic corrosion. For example, the crushing rollers 17 and 18 are made of iron, the roller electrodes 32 and 35 and electrode terminals 45 and 46 are made of copper, and the spacers 33 and 36 and fixing screws 31 and 34 are made of stainless steel.

[0060] Figure 5 is a diagram illustrating the circuit configuration of the moisture content measuring device 11.

[0061] The moisture content measuring device 11 is equipped with a measuring circuit 61. The measuring circuit 61 includes an internal constant current source 62 that outputs a measuring current. The measuring circuit 61 is connected to electrode terminals 45 and 46 via conductors 63 and 64, respectively. Conductor 64 is connected to ground. When grain is being crushed between the circumferential surface of crushing roller 17 and the circumferential surface of crushing roller 18, a measuring current is supplied from the internal constant current source 62 to electrode terminal 45 via conductor 63, and a signal (voltage) corresponding to the potential difference between electrode terminals 45 and 46 that occurs at this time is output from the measuring circuit 61. The larger the electrical resistance between electrode terminals 45 and 46, the larger the potential difference between electrode terminals 45 and 46, so the signal output from the measuring circuit 61 is a signal corresponding to the electrical resistance between electrode terminals 45 and 46.

[0062] <Electrical configuration of a combine harvester> Figure 6 is a block diagram showing the main electrical components of combine harvester 1.

[0063] Combine 1 is equipped with an ECU (Electronic Control Unit) 65. The ECU 65 has a microcontroller, which includes, for example, a CPU, non-volatile memory such as flash memory, and volatile memory such as DRAM (Dynamic Random Access Memory).

[0064] The ECU 65 controls the motor 66 provided in the moisture content measuring device 11 to switch the rotation and stopping of the crushing rollers 17 and 18. The ECU 65 also controls the measuring circuit 61 so that when the grain is being crushed between the circumferential surfaces of the crushing rollers 17 and 18 due to their rotation, a measuring current is supplied from the internal constant current source 62 of the measuring circuit 61 to the electrode terminals 45. The ECU 65 then obtains the electrical resistance value between the electrode terminals 45 and 46 from the signal output by the measuring circuit 61. Furthermore, using the obtained electrical resistance value between the electrode terminals 45 and 46, the ECU 65 uses a calibration curve to determine the moisture content of the grain crushed between the circumferential surfaces of the crushing rollers 17 and 18, i.e., the grain stored in the grain tank 6.

[0065] Furthermore, within the cabin 4, an operation panel 67 is positioned so that a user seated in the driver's seat can see and operate it. The operation panel 67 consists of a touch panel, for example, which is constructed by overlaying pressure-sensitive or capacitive transparent film switches on a display such as an LCD. Various information and images of operation buttons are displayed on the operation panel 67 under the control of the ECU 65. When a user touches an operation button, the operation panel 67 receives an instruction corresponding to the type of operation button that was touched. When an instruction is received by the operation panel 67, a signal corresponding to the content of that instruction is input from the operation panel 67 to the ECU 65.

[0066] <Anomaly detection processing> Figure 7 is a flowchart showing the flow of the anomaly detection process.

[0067] When measuring the moisture content of grains, the ECU65 performs an abnormality detection process.

[0068] In the anomaly detection process, the electrical resistance value between electrode terminals 45 and 46 is obtained from the signal output by the measurement circuit 61 (step S1).

[0069] Then, it is determined whether or not the electrical resistance value exceeds a threshold (step S2).

[0070] If rust occurs between the crushing roller 17 and the electrode terminal 45, such as in the area where the roller electrode 32 and the electrode terminal 45 come into contact, and the conductivity between the crushing roller 17 and the electrode terminal 45 decreases, the electrical resistance between the electrode terminals 45 and 46 will increase. Similarly, if rust occurs between the crushing roller 18 and the electrode terminal 46, such as in the area where the roller electrode 35 and the electrode terminal 46 come into contact, and the conductivity between the crushing roller 18 and the electrode terminal 46 decreases, the electrical resistance between the electrode terminals 45 and 46 will increase. Therefore, if the electrical resistance between the electrode terminals 45 and 46 exceeds a threshold value, it is possible that rust has occurred between the crushing roller 17 and the electrode terminal 45 and / or between the crushing roller 18 and the electrode terminal 46.

[0071] Therefore, if the electrical resistance value between electrode terminals 45 and 46 exceeds a threshold, a message indicating that an abnormality has occurred in the moisture content measuring device 11 is displayed on the operation panel 67, thereby notifying the user of the abnormality in the moisture content measuring device 11 (step S3). By notifying the user of the abnormality in the moisture content measuring device 11, the user of the combine harvester 1 can be prompted to perform maintenance to resolve the abnormality.

[0072] <Effects and Effects> As described above, when grains, which are the harvested product, are being crushed between the circumferential surfaces of the crushing rollers 17 and 18, the measurement circuit 61 outputs a signal corresponding to the electrical resistance value between the electrode terminals 45 and 46. Roller electrodes 32 and 35 are removably attached to the front end surface 27 of the roller shaft 25 of the crushing roller 17 and the front end surface 28 of the roller shaft 26 of the crushing roller 18, respectively. This allows the roller electrodes 32 and 35 to be replaced with rust-free roller electrodes 32 and 35, for example, new roller electrodes 32 and 35, if rust occurs in the local area where the roller electrode 32 and electrode terminal 45 are in contact and / or where the roller electrode 35 and electrode terminal 46 are in contact. By replacing the roller electrodes 32 and 35, poor conductivity due to rust can be prevented between the crushing roller 17 and electrode terminal 45 and between the crushing roller 18 and electrode terminal 46, respectively, and the electrical resistance value between the crushing rollers 17 and 18 can be measured accurately. Consequently, the moisture content of the grain being crushed between the circumferential surfaces of the crushing rollers 17 and 18 can be measured with high accuracy.

[0073] In conventional configurations, the electrode terminals are in direct contact with the shaft of the crushing roller. Therefore, if rust occurs in the area where the crushing roller shaft and the electrode terminals are in contact, the crushing roller must be replaced with a new one, which is time-consuming and costly. In contrast, with the moisture content measuring device 11, if rust occurs in the area where the roller electrode 32 and the electrode terminal 45 are in contact, and / or where the roller electrode 35 and the electrode terminal 46 are in contact, only the roller electrodes 32 and 35 need to be replaced. Compared to conventional moisture content measuring devices, this reduces the effort required for replacement and lowers the cost of replacement.

[0074] The moisture content measuring device 11 comprises a rear case 15 and a front case 21 that house the crushing rollers 17 and 18. The electrode terminals 45 and 46 are detachably mounted on the front case 21. This allows the electrode terminals 45 and 46 to be replaced with new, rust-free electrode terminals 45 and 46 if rust occurs in the area where the roller electrode 32 and the electrode terminal 45 come into contact and / or where the roller electrode 35 and the electrode terminal 46 come into contact. By replacing the electrode terminals 45 and 46, poor conductivity due to rust can be prevented between the crushing roller 17 and the electrode terminal 45, and between the crushing roller 18 and the electrode terminal 46, respectively, allowing for more accurate measurement of the electrical resistance between the circumferential surfaces of the crushing rollers 17 and 18. Consequently, the moisture content of the grain being crushed between the circumferential surfaces of the crushing rollers 17 and 18 can be measured with greater accuracy.

[0075] The roller electrodes 32 and 35 are exposed from the front case 21, and the electrode terminals 45 and 46 are outside the front case 21 and contact the roller electrodes 32 and 35, respectively. This configuration allows the user of the combine harvester 1 to visually check for rust at the points where the roller electrode 32 and electrode terminal 45 come into contact, and at the points where the roller electrode 35 and electrode terminal 46 come into contact.

[0076] Spacers 33 and 36 are interposed between the front end surface 27 of the crushing roller 17 and the roller electrode 32, and between the front end surface 28 of the crushing roller 18 and the roller electrode 35, so that the roller electrodes 32 and 35 are raised from the front case 21. This prevents the roller electrodes 32 and 35 from rubbing against the front case 21 when the crushing rollers 17 and 18 are rotating.

[0077] The moisture content measuring device 11 further includes terminal holding members 43 and 44 fixed to the front case 21, and the electrode terminals 45 and 46 are held by the terminal holding members 43 and 44, respectively, and extend from the terminal holding members 43 and 44, respectively. Since the terminal holding members 43 and 44 are attached to a single mounting base 42, the electrode terminals 45 and 46, the terminal holding members 43 and 44, and the mounting base 42 are integrated as a terminal unit 41. Therefore, by removing the terminal unit 41 from the front case 21 and replacing the terminal unit 41 with a new one, the electrode terminals 45 and 46, the terminal holding members 43 and 44, and the mounting base 42 can all be replaced with new ones at once.

[0078] The roller electrodes 32 and 35 are made of the same type of metal as the electrode terminals 45 and 46. This prevents galvanic corrosion from occurring at the points where the roller electrode 32 and electrode terminal 45 come into contact, and at the points where the roller electrode 35 and electrode terminal 46 come into contact.

[0079] The roller electrode 32 is fixed to the crushing roller 17 by a fixing screw 31, and the roller electrode 35 is fixed to the crushing roller 18 by a fixing screw 34. The roller electrodes 32, 35 and electrode terminals 45, 46 are made of copper, and the fixing screws 31, 34 are made of stainless steel. Since copper and stainless steel have similar natural potentials (ionization tendencies), using stainless steel fixing screws 31, 34 when the roller electrodes 32, 35 are made of copper can suppress the occurrence of galvanic corrosion at the points where the roller electrodes 32, 35 and the fixing screws 31, 34 come into contact. As a result, rust caused by galvanic corrosion can be suppressed on the roller electrodes 32, 35, and poor conductivity due to rust can be further prevented between the crushing roller 17 and electrode terminal 45, and between the crushing roller 18 and electrode terminal 46.

[0080] <Variation> Although one embodiment of the present invention has been described above, the present invention can also be implemented in other forms.

[0081] For example, as shown in Figure 8, the electrode terminals 45 and 46 may have terminal arms 52 and 53 extending vertically, with the middle portion of the terminal arms 52 and 53 being bent so that the terminal contacts 54 and 55 at the tips are in contact with the roller electrodes 32 and 35.

[0082] The bending of the electrode terminals 45 and 46 increases the contact pressure between the terminal contacts 54 and 55 and the roller electrodes 32 and 35. As a result, rust formation can be prevented at the localized contact points between the roller electrodes 32 and 35 and the terminal contacts 54 and 55. Even if rust does occur, the rotation of the crushing rollers (roller electrodes 32 and 35) can scrape off the rust with the terminal contacts 54 and 55. Therefore, poor conductivity due to rust can be prevented between the crushing rollers 17 and 18 and the electrode terminals 45 and 46.

[0083] Furthermore, as shown in Figure 9, grooves 71 and 72 may be formed on the front surface of the mounting base 42 at the mounting positions of the terminal holding members 43 and 44, respectively. Groove 71 has wall surfaces 73 and 74 that face each other in the left-right direction at intervals corresponding to the left-right width of the terminal holding member 43. Groove 72 has wall surfaces 75 and 76 that face each other in the left-right direction at intervals corresponding to the left-right width of the terminal holding member 44. The terminal holding members 43 and 44 may then be fitted into grooves 71 and 72, respectively.

[0084] If electrode terminal 45 contacts roller electrode 32 at a position shifted to the left with respect to the rotation axis of crushing roller 17, and electrode terminal 46 contacts roller electrode 35 at a position shifted to the left with respect to the rotation axis of crushing roller 18, then when the crushing rollers 17 and 18 rotate, electrode terminals 45 and 46 may wobble from side to side, potentially causing unstable contact between electrode terminals 45 and 46 and roller electrodes 32 and 35. By positioning terminal holding members 43 and 44 between the walls 73 and 74 of groove 71 and between the walls 75 and 76 of groove 72, respectively, the wobbling of electrode terminals 45 and 46 from side to side when the crushing rollers 17 and 18 rotate can be suppressed.

[0085] While the combine harvester 1 was used as an example of a harvesting machine, the present invention is not limited to the combine harvester 1, but can also be applied to harvesting machines that harvest vegetables such as carrots, radishes, edamame, and cabbage.

[0086] Furthermore, various design modifications can be made to the aforementioned configuration within the scope of the matters described in the patent claims. [Explanation of Symbols]

[0087] 1: Combine harvester (harvesting machine) 11: Moisture content measuring device 17,18: Crushing roller 21: Front case (case) 25,26: Roller shaft (crushing roller) 27,28: Front end surface (one end surface) 31,34: Fixing screws 32,35: Roller electrodes 33,36: Spacer 42: Mounting base 43,44: Terminal holding member 45,46: Electrode terminal 54, 55: Terminal contacts (tip) 61: Measurement circuit 65: ECU 73, 74, 75, 76: Wall surface

Claims

1. A moisture content measuring device mounted on a harvesting machine, which measures the moisture content of the harvested produce harvested by the harvesting machine, A pair of crushing rollers, whose circumferential surfaces are positioned close to each other and which crush the harvested material between their circumferential surfaces by rotation, A roller electrode is removably attached to one end face of each of the crushing rollers, Each of the roller electrodes has an electrode terminal that contacts it, A moisture content measuring device, comprising: a measuring circuit that outputs a signal corresponding to the electrical resistance value between one electrode terminal and the other electrode terminal when the harvested material is being crushed between the circumferential surface of one crushing roller and the circumferential surface of the other crushing roller.

2. The present invention further includes a case for housing the crushing roller, The moisture content measuring device according to claim 1, wherein the electrode terminals are replaceably attached to the case.

3. The roller electrode is exposed from the case, The moisture content measuring device according to claim 2, wherein the electrode terminals contact the roller electrode outside the case.

4. The present invention further includes a spacer interposed between the one end face of the crushing roller and the roller electrode, The moisture content measuring device according to claim 3, wherein the roller electrode is suspended from the case.

5. The present invention further includes a terminal holding member fixed to the case, The moisture content measuring device according to claim 2, wherein the electrode terminal is held by the terminal holding member and extends from the terminal holding member.

6. The moisture content measuring device according to claim 5, wherein the electrode terminal extends in a direction intersecting the rotation axis of the crushing roller, and the tip is bent in a direction approaching the roller electrode midway, and the tip is in contact with the roller electrode.

7. The moisture content measuring device according to claim 5, further comprising a mounting base to which the terminal holding member is attached and which is attached to the case.

8. The electrode terminals are in contact with the roller electrodes at a position offset in a predetermined direction with respect to the rotation axis of the crushing roller. The mounting base has a pair of wall surfaces facing each other in the predetermined direction, The moisture content measuring device according to claim 7, wherein the terminal holding member is arranged between the pair of wall surfaces.

9. The moisture content measuring device according to claim 7 or 8, wherein the electrode terminal, the terminal holding member, and the mounting base are integrated by being attached to a single mounting base.

10. The crushing roller is made of a different metal from the electrode terminals. The moisture content measuring device according to claim 1, wherein at least the portion of the roller electrode that contacts the electrode terminal is made of the same type of metal as the electrode terminal.

11. The roller electrode is fixed to the crushing roller by a fixing screw. The moisture content measuring device according to claim 10, wherein the fixing screw is made of a different metal from the roller electrode.

12. The crushing roller is made of iron, The roller electrode and the electrode terminal are made of copper. The moisture content measuring device according to claim 11, wherein the fixing screw is made of stainless steel.

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