detector

Abstract

To provide a technology for reducing energy consumption of a detector which detects a number of rotation of a rotating needle of a measuring meter.SOLUTION: A detector according to an aspect of the present invention includes: a magnet arranged on a rotating needle; a magnetic sensor for measuring an angle of the rotating needle on the basis of a magnetic field of the magnet, and an arithmetic operation device. An angle space of the rotation of the rotating needle is divided according to a first condition. The number of divisions of the first condition is three or more. A reference value is obtained by dividing the minimum rotation period of the rotating needle by the number of divisions of the first condition. The arithmetic operation device acquires a measurement result from the magnetic sensor at a time interval shorter than the reference value, and calculates the rotation number of the rotating needle by detecting that the rotating has circulated in a section area of the first condition in the angle space on the basis of the acquired measurement result.SELECTED DRAWING: Figure 10A

Description

[Technical Field]

[0001] The present invention relates to a detector for reading the meter of an instrument such as a flow meter. [Background technology]

[0002] Various methods have been developed to detect the rotation of a rotary pointer in a meter such as a flow meter. For example, Patent Document 1 proposes a water meter equipped with a unit that uses magnetism to detect the rotation of a rotary pointer (pointer). Specifically, in the water meter proposed in Patent Document 1, a pair of magnets are attached to the rotary pointer, and a magnetic sensor is placed above the rotary pointer. The flow rate indicated by the meter is detected based on the detection result of the magnetic sensor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5873686 Summary of the Invention [Problem to be solved by the invention]

[0004] In the magnetic method proposed in Patent Document 1 and elsewhere, the direction of the magnetic field generated by a magnet attached to the rotating hand changes as the rotating hand rotates. By measuring the direction of this magnetic field with a magnetic sensor, the angle of the rotating hand can be measured. However, the present inventors have discovered that this magnetic method has the following problems.

[0005] That is, the rotating hand can rotate in both the forward direction (clockwise) and the reverse direction (counterclockwise). In order to identify the direction of rotation and measure the number of rotations of the rotating hand, measurements must be performed continuously using a magnetic sensor. To avoid misidentifying the direction of rotation, it is preferable to perform measurements using the magnetic sensor continuously at shorter time intervals. However, performing measurements using the magnetic sensor continuously at short time intervals increases the amount of energy consumed to drive the magnetic sensor. With conventional methods, it has been difficult to identify the direction of rotation and efficiently measure the number of rotations of the rotating hand.

[0006] In one aspect, the present invention has been made in consideration of the above-described situation, and its purpose is to provide a technology for reducing energy consumption in a detector that detects the number of rotations of a rotary needle in an instrument. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, the present invention employs the following configuration.

[0008] That is, a detector according to one aspect of the present invention is used in an instrument having an axis and a rotating hand configured to rotate around the axis. The detector includes a magnet placed on the rotating hand of the instrument, a magnetic sensor configured to measure the angle of the rotating hand based on the direction of a magnetic field generated by the magnet, and a computing device. The angular space of the rotation of the rotating hand is divided according to a first condition. The number of partitioned areas formed by the division according to the first condition is three or more and is less than the number of scale marks on the instrument. The computing device is configured to continuously obtain measurement results of the angle of the rotating hand from the magnetic sensor by operating the magnetic sensor at time intervals shorter than a reference value, and to calculate the number of rotations of the rotating hand based on the obtained measurement results by detecting that the rotating hand has circulated through the partitioned areas formed by the division according to the first condition in the angular space. The reference value is obtained by dividing the minimum rotation period of the rotating hand by the number of partitioned areas formed by the division according to the first condition.

[0009] In a detector having this configuration, the angular space of the rotary pointer is divided into a plurality of division areas according to a first condition in order to detect the number of rotations of the rotary pointer. The number of division areas formed by the division of the first condition (hereinafter also referred to as the "number of divisions of the first condition") is set to a natural number equal to or greater than three and less than the number of graduations. The number of graduations may be any natural number greater than three. In a typical example, the number of graduations is 10 (for example, a 1-liter meter, a 10-liter meter, etc. of a flow meter).

[0010] Furthermore, the time interval for driving the magnetic sensor (for measuring the angle of the rotating hand) is set to less than a reference value. The reference value is obtained by dividing the minimum rotation period of the rotating hand by the division number of the first condition. In other words, this reference value corresponds to the time it takes for the rotating hand to change the angle of one segment when rotating at the minimum period (maximum speed). By setting the time interval for measuring the angle of the rotating hand to less than this reference value, the number of segment changes due to the rotation of the rotating hand over the time from any measurement time to the next measurement time (hereinafter also referred to as "one sampling time") can be reduced to one or less. In other words, even if the rotating hand is rotating at the maximum speed, it is possible to prevent a situation in which a rotating hand belonging to a certain segment skips an adjacent segment and changes to two or more segments ahead after one sampling time has elapsed.

[0011] Because the number of divisions in the first condition is three or more, by specifying the measurement time interval (measurement timing) in this manner, it is possible to prevent the rotating hand from reaching the same segmented area after one sampling time has elapsed when the rotating hand rotates in both the forward and reverse directions. As an example, assume that the number of divisions in the first condition is four, and that at a certain measurement time, the rotating hand belongs to the first segmented area of ​​four segmented areas (first to fourth segmented areas, in order). In this case, by specifying the measurement timing as described above, the segmented area that can be reached after one sampling time has elapsed when the rotating hand rotates in the forward direction is the second segmented area. On the other hand, the segmented area that can be reached after one sampling time has elapsed when the rotating hand rotates in the reverse direction is the fourth segmented area. In this way, by specifying the measurement timing as described above, it is possible to prevent the rotating hand from reaching the same segmented area after one sampling time has elapsed for both forward and reverse rotations. This makes it possible to identify the transition direction when the rotating hand circulates through the segmented areas. In other words, it is possible to identify whether the rotating hand has transitioned in the forward or reverse direction. Therefore, the number of rotations of the rotary hand can be calculated based on the circulation of the divided areas by the rotary hand.

[0012] In addition, by bringing the measurement time interval closer to the reference value, the number of times the magnetic sensor is driven while the rotating hand remains in one segmented area can be reduced. When the rotating hand is rotating at maximum speed, by bringing the measurement time interval closer to the reference value, the number of times the magnetic sensor is driven while the rotating hand belongs to each segmented area can be optimally reduced to one. By setting the number of segmented areas to be less than the number of scales, the number of times the magnetic sensor is driven during one rotation of the rotating hand can be optimally reduced to less than the number of scales. In other words, with this configuration, the number of times the magnetic sensor is driven when measuring the rotation speed of the rotating hand can be reduced using the reference value as an index. Therefore, with this configuration, energy consumption can be reduced in a detector that detects the rotation speed of a rotating hand in an instrument.

[0013] In the detector according to the above aspect, the angular space of rotation of the rotating hand may be further divided according to a second condition, in addition to the first condition. The number of divided areas formed by the division according to the second condition (hereinafter also referred to as the "number of divisions according to the second condition") may be greater than the number of divided areas formed by the division according to the first condition, and may correspond to the number of scales on the instrument. The calculation device is further configured to calculate the scale indicated by the rotating hand by identifying the divided area to which the rotating hand belongs from among the divided areas formed by the division according to the second condition, based on the measurement results obtained from the magnetic sensor. According to this configuration, it is possible to detect the scale to which the rotary hand is pointing, as well as the number of rotations of the rotary hand.

[0014] In the detector according to the above aspect, the number of divisions formed by dividing the second condition may be the same as the number of scale marks on the instrument. With this configuration, the number of divisions of the second condition corresponds one-to-one to the number of scale marks, so the scale mark can be directly identified from the division of the second condition to which the rotating hand belongs. This simplifies the process of detecting the scale mark indicated by the rotating hand, and reduces the calculation cost.

[0015] In the detector according to the above aspect, the time interval for operating the magnetic sensor (hereinafter also referred to as the "measurement time interval") may be set to satisfy at least one of the following formulas 1, 2, and 3.

[0016]

number

number

number

[0017] According to Equation 1, when the rotating hand rotates at maximum speed, the number of times the magnetic sensor is driven per rotation can be kept below the number of graduations. According to Equation 2, it is possible to avoid a situation where the magnetic sensor is driven more than once in all the divided areas while the rotating hand rotates at maximum speed. In other words, it is possible to keep the number of times the magnetic sensor is driven to just once in at least some of the divided areas. Therefore, it is possible to reduce the number of times the magnetic sensor is driven per rotation. In Equation 3, the measurement time interval (T i ) lower limit (T min / (M+k)) is the lower limit of Equation 2 (T min / 2M). Therefore, according to Equation 3, the number of times the magnetic sensor is driven can be reduced even more than with Equation 2. Therefore, by setting the measurement time interval to satisfy at least one of Equations 1 to 3, the number of times the magnetic sensor is driven can be reduced as described above when measuring the number of rotations of the rotating hand. This makes it possible to reduce energy consumption in the detector.

[0018] In the detector according to the above aspect, the number of partitioned regions formed by dividing the first condition may be four or less. The reference value is inversely proportional to the number of divisions of the first condition. The larger the reference value, the longer the measurement time interval can be. In other words, there is a large margin for reducing energy consumption. Therefore, according to this configuration, by setting the division number of the first condition to 3 or 4, it is possible to easily reduce energy consumption.

[0019] In the detector according to the above aspect, the magnet may be disposed on the axis of the rotating needle. Because the magnet is disposed on the rotating needle, the magnet also rotates as the rotating needle rotates. The closer the magnet is disposed to the tip of the rotating needle, the greater the stress on the rotating needle due to the rotation of the magnet, which may result in severe wear of the rotating needle. In contrast, according to this configuration, by disposing the magnet on the axis of the rotating needle, such wear can be reduced and the life of the meter can be extended.

[0020] In the detector according to the above aspect, the meter may further include a transparent cover plate that covers the rotary needle. The magnetic sensor and the computing device may be attached to the transparent cover plate. With this configuration, the detector can be appropriately positioned relative to the meter that includes the transparent cover plate.

[0021] The detector according to the above aspect may further include a communication device connected to the arithmetic device and configured to transmit the calculation result of the arithmetic device via wireless communication. With this configuration, it is possible to provide a detector capable of transmitting the calculation result of the arithmetic device via wireless communication.

[0022] In the detector according to the above aspect, the meter may be a flow meter for measuring a flow rate of a liquid. With this configuration, it is possible to reduce energy consumption when detecting the number of rotations of a rotary needle in the flow meter.

[0023] The above standard value (T min / M) specifies the measurement timing so that the number of transitions of the segmented areas in one sampling time is one or less. It is assumed that the measurement timing is set to allow a natural number of transitions of the segmented areas that is equal to or greater than half the number of divisions (number of segmented areas) in the first condition. Under this assumption, if the rotating needle rotates (transitions between segmented areas) in both the forward and reverse directions in one sampling time from any segmented area, there is a possibility that the same segmented area will be reached from that any segmented area. This makes it difficult to distinguish between transitions in each direction. On the other hand, if the measurement timing is set so that the number of transitions of the segmented areas allowed in one sampling time is a natural number that is less than half the number of divisions in the first condition, the transitions described above will not occur. Therefore, in order to distinguish between transitions in the forward and reverse directions, it is sufficient that the measurement timing is set to satisfy such a condition. The reference value (T min / M) is an example of such a condition, and the timing specified by the reference value is an example of a timing at which transitions in the forward and reverse directions can be distinguished. However, the reference value for the measurement timing is not limited to this example. The reference value may be determined as appropriate so as to specify a measurement timing that satisfies the above condition. In another example, the time interval T for operating the magnetic sensor is i may be set to satisfy the conditions of the following formulas 4 and 5. In this case, the greater the number of divisions in the first condition, the greater the number of transitions between the divided regions permitted in one rotation of sampling time. Therefore, even if the number of divisions in the first condition is large, it is possible to reduce energy consumption. Therefore, when the conditions of formulas 4 and 5 are adopted as the reference values, the number of divisions in the first condition does not have to be less than the number of divisions on the instrument (that is, it may be greater than or equal to the number of divisions on the instrument).

[0024] That is, a detector according to one aspect of the present invention is used in an instrument having an axis and a rotating hand configured to rotate around the axis. The detector comprises a magnet placed on the rotating hand, a magnetic sensor configured to measure the angle of the rotating hand based on the direction of a magnetic field generated by the magnet, and a computing device. The angular space of the rotation of the rotating hand is divided according to a first condition. The number of partitioned areas formed by the division according to the first condition is three or more. The computing device operates the magnetic sensor at time intervals that satisfy the conditions of Equations 4 and 5, thereby continuously obtaining measurement results of the angle of the rotating hand from the magnetic sensor, and based on the obtained measurement results, detects that the rotating hand has circulated through the partitioned areas formed by the division according to the first condition in the angular space, thereby The number of rotations of the rotating needle is calculated. In this configuration, the upper limit value (M / 2-q)(T min / M) is the standard value.

[0025]

number

number

[0026] As another embodiment of the detector according to each of the above embodiments, the detector may be an information processing method for realizing each of the above configurations, a program, or a storage medium on which such a program is recorded and which can be read by a computer or other device, machine, etc. Here, a computer-readable storage medium is a medium that stores information such as a program by electrical, magnetic, optical, mechanical, or chemical action. [Effects of the Invention]

[0027] According to the present invention, it is possible to reduce energy consumption in a detector that detects the number of rotations of a rotary needle in an instrument. [Brief explanation of the drawings]

[0028] [Figure 1] FIG. 1 is a schematic diagram showing an example of a scene in which a detector according to an embodiment is used. [Figure 2A] FIG. 2A is a schematic diagram showing an example of a detector according to an embodiment as viewed from above. [Figure 2B] FIG. 2B is a schematic diagram showing an example of the detector according to the embodiment as viewed from the side. [Figure 2C] FIG. 2C schematically illustrates an example of the configuration of a detector according to the embodiment. [Figure 3] FIG. 3 is a schematic diagram showing an example of division of the angle space based on the first condition according to the embodiment. [Figure 4] FIG. 4 is a schematic diagram showing an example of division of the angle space based on the second condition according to the embodiment. [Figure 5A] FIG. 5A shows a schematic example of the measurement results of the magnetic sensor when the rotating needle rotates in the forward direction. [Figure 5B] FIG. 5B shows a schematic example of the measurement results of the magnetic sensor when the rotating hand rotates in the reverse direction. [Figure 6] FIG. 6 is a diagram illustrating an example of a hardware configuration of a calculation device according to an embodiment. [Figure 7] FIG. 7 is a diagram illustrating an example of a software configuration of the arithmetic device according to the embodiment. [Figure 8] FIG. 8 is a flowchart illustrating an example of a processing procedure of the detector (arithmetic device) according to the embodiment. [Figure 9A] FIG. 9A schematically shows an example of the relationship between the rotating needle and the partitioned areas when the rotating needle rotates in the forward direction. [Figure 9B]FIG. 9B schematically shows an example of the relationship between the rotating hand and the partitioned areas when the rotating hand rotates in the opposite direction. [Figure 10A] FIG. 10A shows an example of the measurement result (sin θ) of the magnetic sensor when the rotating needle rotates forward by 72 degrees in one sampling time. [Figure 10B] FIG. 10B shows an example of the measurement result (cos θ) of the magnetic sensor when the rotating needle rotates forward by 72 degrees in one sampling time. [Figure 11] FIG. 11 shows an example of the relationship between the measurement results of the magnetic sensor, the division area to which the rotating hand belongs, and the calculation results of the arithmetic unit when the rotating hand rotates forward by 72 degrees in one sampling time. [Figure 12] FIG. 12 shows an example of the relationship between the measurement results of the magnetic sensor, the division area to which the rotating hand belongs, and the calculation results of the arithmetic unit when the rotating hand rotates forward by 85 degrees in one sampling time. DETAILED DESCRIPTION OF THE INVENTION

[0029] An embodiment according to one aspect of the present invention (hereinafter also referred to as "the present embodiment") will be described below with reference to the drawings. However, the present embodiment described below is merely an example of the present invention in all respects. Various improvements or modifications may be made without departing from the scope of the present invention. In implementing the present invention, specific configurations according to the embodiment may be appropriately adopted. Note that while data appearing in the present embodiment is described in natural language, more specifically, it is specified using computer-recognizable pseudo-language, commands, parameters, machine language, etc.

[0030] §1 Configuration example [Instruments] FIG. 1 schematically shows an example of a usage scenario for the detector 1 according to this embodiment. The detector 1 according to this embodiment is used in a meter having an axis and a rotating needle configured to rotate around the axis. The rotating needle indicates the measurement result of the meter. The rotating needle may be interpreted as a pointer, a liter needle, or the like, depending on the type of meter. The type of meter is not particularly limited as long as it measures the state of an object (e.g., the amount of fluid) by rotating the rotating needle, and may be selected appropriately depending on the embodiment. In one example, the meter may be a flow meter for measuring the amount of liquid. In a typical example, the liquid may be water. Meter F in FIG. 1 is an example of a meter in which the detector 1 is used.

[0031] In the example of Figure 1, meter F is a dry-type water meter. A dry-type water meter is an example of a flow meter. Meter F includes a transparent cover plate T, a display unit D, a 1-liter meter M1, and a 10-liter meter M10. In addition, meter F may include a pilot mark. Meter F has a cylindrical housing with an open top. The housing has an internal space. The display unit D and each meter (M1, M10) are housed in the internal space of the housing. The top of the housing is closed by a transparent cover plate T. As a result, each meter (M1, M10) is covered by the transparent cover plate T, and the internal space is sealed.

[0032] The 1-liter meter M1 is configured to indicate the flow rate of water in 1-liter increments using a rotary pointer. The 10-liter meter M10 is configured to indicate the flow rate of water in 10-liter increments using a rotary pointer. The display D is configured to indicate the flow rate of water in 1-liter increments using a counter. 3 In the example of FIG. 1, the detector 1 is applied to a 1-liter meter M1. However, the application of the detector 1 is not limited to this example. In another example, the detector 1 is configured to indicate the flow rate of water in 10 It may be applied to a liter meter M10. In yet another example, the detector 1 may be applied to any meter equipped with a rotating needle.

[0033] [Detector] 2A is a schematic diagram showing an example of the detector 1 according to this embodiment as viewed from above. FIG. 2B is a schematic diagram showing an example of the detector 1 according to this embodiment as viewed from the side. FIG. 2C is a schematic diagram showing an example of the configuration of the detector 1 according to this embodiment. The detector 1 according to this embodiment includes a magnet 11, a substrate 12, a magnetic sensor 15, a computing device 16, and a communication device 17.

[0034] <Magnet> 2A and 2B, the one-liter meter M1 includes a dial plate 20, a shaft 21, and a rotating needle 22. The dial plate 20 has ten graduations (0 to 9). The shaft 21 is disposed in the center of the dial plate 20. The rotating needle 22 is fixed to the shaft 21 and is configured to be rotatable in a forward direction (clockwise) and a reverse direction (counterclockwise) around the shaft 21 in response to the measurement of the water flow rate.

[0035] The magnet 11 is disposed on the rotary pointer 22. As shown in the figure, in one example, the magnet 11 may be disposed on the axis 21 of the rotary pointer 22. This reduces wear on the rotary pointer 22 caused by the magnet 11 and extends the life of the meter F. However, the arrangement of the magnet 11 is not limited to this example. The magnet 11 may be attached to a region of the rotary pointer 22 other than on the axis 21.

[0036] The type of magnet 11 is not particularly limited as long as it can generate a magnetic field that allows the angle of the rotary pointer 22 to be measured, and may be selected appropriately depending on the embodiment. Any magnet, including known magnets, may be used for the magnet 11. In one example, the magnet 11 may be formed in a flat cylindrical shape and configured to generate a magnetic field in a horizontal direction relative to the rotary pointer 22 (the direction of a plane parallel to the extension direction of the rotary pointer 22). As a result, as the rotary pointer 22 rotates, the magnet 11 rotates on the axis 21, changing the direction of the magnetic field. Therefore, the angle of the rotary pointer 22 can be measured from the direction of the magnetic field generated by the magnet 11.

[0037] <Substrate> 2A to 2C, the substrate 12 is formed in a rectangular flat plate shape. However, the form of the substrate 12 is not limited to this example. The material, shape, and dimensions of the substrate 12 may be determined appropriately depending on the embodiment.

[0038] In this embodiment, the magnetic sensor 15, the computing device 16, and the communication device 17 are attached to the substrate 12. In one example, the magnetic sensor 15, the computing device 16, and the communication device 17 may be attached to a transparent cover plate T that covers the rotary pointer 22 via the substrate 12. The surface of the substrate 12 on which the magnetic sensor 15, the computing device 16, and the communication device 17 are arranged may be selected appropriately depending on the embodiment. This allows the detector 1 to be appropriately positioned with respect to the meter F.

[0039] In the example of Fig. 2B, the substrate 12 is attached to the outer surface of the transparent cover plate T. The substrate 12 may be fixed to the transparent cover plate T by, for example, screws, adhesive, etc. The magnetic sensor 15, the computing device 16, and the communication device 17 are attached to the surface of the substrate 12 opposite to the surface facing the meter F (the upper surface in Fig. 2B).

[0040] However, the arrangement of the substrate 12, the magnetic sensor 15, the computing device 16, and the communication device 17 need not be limited to this example. In another example, the substrate 12 may be attached to the inner surface of the transparent cover plate T. The substrate 12 may be arranged in any location other than the transparent cover plate T. The substrate 12 may be omitted. At least the magnetic sensor 15, the computing device 16, and the communication device 17 may be attached to the inner surface of the transparent cover plate T. Any of them may be attached to the surface of the substrate 12 facing the instrument F (the lower surface in FIG. 2B ). At least one of the magnetic sensor 15, the computing device 16, and the communication device 17 may be disposed anywhere other than on the substrate 12.

[0041] As long as the magnetic sensor 15 can capture the magnetic field generated by the magnet 11, the location of the magnetic sensor 15 is not particularly limited and may be determined appropriately depending on the embodiment. As long as the arithmetic device 16 can be connected to the magnetic sensor 15, the location of the arithmetic device 16 is not particularly limited and may be determined appropriately depending on the embodiment. As long as the communication device 17 can transmit the calculation result of the arithmetic device 16 to the external computer UT, the location of the communication device 17 is not particularly limited and may be determined appropriately depending on the embodiment. The magnetic sensor 15, the arithmetic device 16, and the communication device 17 may be supplied with power by any method, such as a battery, wireless power supply, or solar power supply.

[0042] <Angle space> (First condition) The angle (0 degrees to 360 degrees) of one revolution of the rotary hand 22 can be expressed as an angle space. The angle space is a space that expresses the angle of the rotary hand 22. In this embodiment, the angle space of the rotation of the rotary hand 22 is divided into a plurality of segmented areas by a first condition. The first condition is set in order to detect the number of rotations of the rotary hand 22. The first condition defines the number of segmented areas formed when dividing the angle space at equal intervals. The segmented areas are areas formed by dividing the angle space (0 degrees to 360 degrees).

[0043] In this embodiment, the number of segmented areas formed by the division of the first condition (the number of divisions of the first condition) may be set to three or more and less than the number of markings on the gauge F (in this embodiment, the 1-liter meter M1). The angle of each segmented area formed by the division of the first condition is, for example, 120 degrees if divided into three, 90 degrees if divided into four, and 72 degrees if divided into five.

[0044] FIG. 3 schematically shows an example of division of an angle space according to the first condition of this embodiment. In the example of FIG. 3, the number of divisions under the first condition is four. Four segmented areas A1 to A4 are formed by the division under the first condition. In the example of FIG. 3, the first segmented area A1 is set to represent 0 to 90 degrees. The second segmented area A2 is set to represent 90 to 180 degrees. The third segmented area A3 is set to represent 180 to 270 degrees. The fourth segmented area A4 is set to represent 270 to 360 degrees. However, the relationship between each segmented area A1 to A4 and the angle is not limited to this example and may be determined appropriately depending on the embodiment.

[0045] In the following embodiment, for convenience of explanation, the number of divisions for the first condition is set to 4, and the first to fourth divided areas A1 to A4 are also referred to as the first to fourth quadrants. However, the number of divisions for the first condition does not have to be limited to 4. In another example, the number of divisions for the first condition may be 3. The number of divisions for the first condition may be greater than 4 and less than the number of scale marks (10 in this embodiment).

[0046] In this embodiment, the upper limit (reference value) of the measurement time interval is obtained by dividing the minimum rotation period of the rotary pointer 22 by the division number of the first condition. In other words, the division number of the first condition (the angle of each divided area of ​​the first condition) is used as an index for obtaining the upper limit (reference value) of the measurement time interval. The smaller the division number of the first condition (i.e., the larger the angle of each divided area of ​​the first condition), the larger the reference value. Therefore, the smaller the division number of the first condition, the longer the measurement time interval and the easier it is to reduce energy consumption. Therefore, it is desirable that the division number of the first condition be a value close to 3. In one example, the number of divided areas formed by dividing the first condition may be four or less (i.e., 3 or 4).

[0047] (Second condition) In this embodiment, the angular space of rotation of the rotary hand 22 may be further divided by a second condition, in addition to the first condition. The second condition is set in order to detect the scale indicated by the rotary hand 22. Like the first condition, the second condition also defines the number of partitioned areas formed when the angular space is divided at equal intervals. The number of partitioned areas formed by the division under the second condition (the number of divisions under the second condition) may be set to be greater than the number of partitioned areas formed by the division under the first condition and to correspond to the number of scales on the meter F (in this embodiment, the 1-liter meter M1).

[0048] [Table 1] FIG. 4 schematically shows an example of the division of the angular space according to the second condition of this embodiment. In the example of FIG. 4, the number of divisions according to the second condition is 10, which is the same as the number of scales (10). Ten segmented regions B0 to B9 are formed by the division according to the second condition. The correspondence between each segmented region B0 to B9, the angle, and the scale is as shown in Table 1. However, the correspondence between each segmented region B0 to B9, the angle, and the scale is not limited to this example and may be determined appropriately depending on the embodiment. In the following embodiment, for convenience of explanation, the number of divisions and the number of scales according to the second condition are set to 10. However, the number of divisions and the number of scales according to the second condition are not limited to this example and may be determined appropriately depending on the embodiment.

[0049] In this embodiment, each of the sectional areas B0 to B9 of the second condition is used to calculate the scale indicated by the rotary hand 22. That is, the scale indicated by the rotary hand 22 is calculated by identifying the sectional area to which the rotary hand 22 belongs among the sectional areas B0 to B9 of the second condition. Therefore, as illustrated in FIG. 4, it is preferable that the number of sectional areas formed by dividing the second condition be the same as the number of scales on the instrument. In other words, the correspondence to the number of scales on the instrument may be achieved by a one-to-one correspondence between the number of divisions of the second condition and the number of scales. This makes it possible to directly identify the scale from the sectional area of ​​the second condition to which the rotary hand belongs. This simplifies the process of detecting the scale indicated by the rotary hand, thereby reducing the calculation cost.

[0050] However, the correspondence between the number of divisions in the second condition and the number of scales on the instrument does not have to be limited to this example. Correspondence to the number of scales on the instrument F may be made as long as it is possible to narrow down the scales indicated by the rotary needle by specifying the division area to which the rotary needle belongs. As another example, the correspondence between the number of divisions in the second condition and the number of scales may be a specific ratio, such as 2:1 (two division areas are assigned to one scale) or 1:2 (one division area is assigned to two scales).

[0051] <Magnetic sensor> In this embodiment, the magnetic sensor 15 is configured to measure the angle of the rotating hand 22 based on the direction of the magnetic field generated by the magnet 11. In the example of FIG. 2B, the magnetic sensor 15 is disposed above the magnet 11. The magnetic sensor 15 is configured to measure the angle of the rotating hand 22 by measuring the direction of the horizontal magnetic field applied by the magnet 11. The type of the magnetic sensor 15 is not particularly limited as long as it can capture the magnetic field of the magnet 11 and measure the angle of the rotating hand 22, and may be selected appropriately depending on the embodiment. The magnetic sensor 15 may be any magnetic sensor including a known magnetic sensor (for example, KG1402-61 manufactured by Hamamatsu Koden Co., Ltd.). A sensor may be used.

[0052] The magnetic sensor 15 may be configured to output the angle measurement result in any format. In one example, the magnetic sensor 15 may be configured to output the angle measurement result as sin θ and cos θ values. In the following embodiment, for convenience of explanation, it is assumed that the magnetic sensor 15 is configured to output the angle measurement result in these formats. However, the output format of the magnetic sensor 15 is not limited to this example. In another example, the magnetic sensor 15 may be configured to directly output the value of the angle θ as the measurement result.

[0053] FIG. 5A shows the measurement result (sin 5B shows an example of the rotation angle (θ, cosθ) when the rotary needle 22 rotates in the reverse direction. 10A and 10B are diagrams showing an example of the measurement results (sin θ, cos θ) of the magnetic sensor 15. The magnetic sensor 15 is connected to the arithmetic unit 16. The arithmetic unit 16 substitutes the measurement results (sin θ, cos θ) of the magnetic sensor 15 into the following equation 6 and executes the calculation process of equation 6 to calculate the angle θ of the rotating needle 22.

[0054]

number

[0055] <Communication Device> In this embodiment, the communication device 17 is connected to the arithmetic device 16. The communication device 17 is configured to transmit the results of calculations by the arithmetic device 16 via wireless communication. A known method such as Wi-Fi (registered trademark) or Bluetooth (registered trademark) may be adopted as the wireless communication method. The communication device 17 may be a communication module made up of one or more semiconductors. Any communication device including a known communication device (for example, an RL78 / G1D module manufactured by Renesas Electronics Corporation) may be used as the communication device 17.

[0056] In this embodiment, by providing the communication device 17, it is possible to provide a detector 1 capable of transmitting the calculation results of the arithmetic device 16 by wireless communication. A user can receive the calculation results of the arithmetic device 16 by using an external computer UT. The external computer UT may be a computer designed specifically for the service provided, or may be a general-purpose computer, a mobile phone including a smartphone, a tablet PC (personal computer), or any other computer capable of wireless communication. The computer may be any computer configured to:

[0057] <Arithmetic device> In this embodiment, the arithmetic device 16 is connected to the magnetic sensor 15 and the communication device 17. The arithmetic device 16 is configured to continuously obtain the calculation result of the angle of the rotary pointer 22 from the magnetic sensor 15 by operating the magnetic sensor 15 at time intervals shorter than a reference value. Furthermore, the calculation device 16 is configured to calculate the number of rotations of the rotary pointer 22 by detecting that the rotary pointer 22 has circulated through the divided areas (A1 to A4) formed by the division of the first condition in the angle space based on the acquired measurement results.

[0058] In this embodiment, the reference value (T min / M) is obtained by dividing the minimum rotation period of the rotary pointer 22 by the number of division areas (A1 to A4) formed by dividing the first condition. The minimum rotation period of the rotary pointer 22 may be given as appropriate. In one example, the rotation period of the rotary pointer 22 may be measured while using the meter F for a predetermined period. The minimum value of the measured rotation periods may be obtained as the minimum rotation period. In another example, the minimum rotation period may be obtained from the specifications or standards of the meter F. For example, as in this embodiment, assume that the meter F is a flow meter and the detector 1 is used as a 1-liter meter. In this case, the minimum rotation period may be calculated from the limit flow rate specified in the specifications (performance) of the flow meter. As a specific example, max is 20 [m 3 / h] = (20 × 1000) / (60 × 60) [liters / second]. The rotating needle (liter needle) of a 1 liter meter indicates a flow rate of 10 liters per revolution, so the minimum rotation period is 10 ÷ F max = 1.8 [seconds].

[0059] Reference value (T min / M) is the time interval (measurement time interval) T for operating the magnetic sensor 15. i The upper limit of the measurement time interval T i The lower limit of the time interval T i may be set to satisfy at least one of the above formulas 1, 2, and 3.

[0060] The lower limit of Equation 1 (T min / H), when the rotary hand 22 rotates at the maximum speed, the number of times the magnetic sensor 15 is driven per rotation can be kept below the number of graduations. min / 2M), it is possible to avoid a situation in which the magnetic sensor 15 is driven more than once in all the divided areas A1 to A4 while the rotary hand 22 makes one rotation at the maximum speed. In other words, it is possible to limit the number of times the magnetic sensor 15 is driven to just one in at least one of the divided areas A1 to A4. Therefore, it is possible to reduce the number of times the magnetic sensor 15 is driven per rotation. In Equation 3, the measurement time interval T i The lower limit of (T min / (M+k)) is the lower limit of Equation 2 (T min / 2M). Therefore, according to Equation 3, the number of times the magnetic sensor 15 is driven can be further reduced compared to Equation 2. Therefore, the measurement time interval T i By setting so as to satisfy at least one of the formulas 1 to 3, it is possible to reduce the number of times that the magnetic sensor 15 is driven when measuring the number of rotations of the rotary pointer 22. This makes it possible to reduce energy consumption in the detector 1.

[0061] Furthermore, in this embodiment, the angular space of the rotating hand 22 may be further divided according to the second condition. Accordingly, the calculation device 16 may be further configured to calculate the scale indicated by the rotating hand 22 by identifying the segmented area (B0 to B9) to which the rotating hand 22 belongs, based on the measurement results obtained from the magnetic sensor 15. This makes it possible to detect the scale indicated by the rotating hand 22 as well as the rotation speed of the rotating hand 22.

[0062] The configuration of the arithmetic unit 16 is not particularly limited as long as it is a computer capable of executing the above-described arithmetic processes, and may be determined appropriately depending on the embodiment. In a typical example, the arithmetic unit 16 may be configured by a microcomputer. The arithmetic unit 16 may be a arithmetic module configured by one or more semiconductors.

[0063] (Hardware configuration) FIG. 6 is a diagram showing an example of the hardware configuration of the arithmetic device 16 according to this embodiment. The arithmetic device 16 according to the embodiment is a computer in which a processor 161, a memory 162, and an input / output interface 163 are electrically connected.

[0064] The processor 161 may be, for example, a CPU (Central Processing Unit), a microprocessor, or the like. The memory 162 includes, for example, a RAM, a ROM, etc., and is configured to execute information processing based on programs and various data. The memory 162 includes, for example, a RAM, a ROM, etc., and stores various information such as a program 81. The program 81 is a program for causing the arithmetic unit 16 to execute information processing (see FIG. 8 described below) for detecting the number of rotations of the rotary pointer 22 of the gauge F. The program 81 includes a series of instructions for this information processing.

[0065] The input / output interface 163 is, for example, a USB (Universal Serial Bus) port, a dedicated port, or the like, and is an interface for connecting to an external device. The type and number of input / output interfaces 163 may be determined appropriately depending on the type and number of external devices to be connected. In this embodiment, the arithmetic unit 16 may be connected to the magnetic sensor 15 and the communication unit 17 via the input / output interface 163.

[0066] The program 81 may be stored in a storage medium 91. Accordingly, the arithmetic device 16 may acquire the program 81 from the storage medium 91. The storage medium 91 is a medium that stores information such as a program by electrical, magnetic, optical, mechanical, or chemical action so that a computer or other device, machine, etc. can read the various information stored therein. The type of the storage medium 91 is not particularly limited and may be selected appropriately depending on the embodiment. A drive device may be used to read various information from the storage medium 91. The drive device may be connected to the arithmetic device 16 via the input / output interface 163. The type of drive device may be selected appropriately depending on the type of the storage medium 91.

[0067] The above hardware configuration of the arithmetic unit 16 is merely an example. Regarding the specific hardware configuration of the arithmetic unit 16, components can be omitted, replaced, or added as appropriate depending on the embodiment. For example, the arithmetic unit 16 may include a timer.

[0068] (Software configuration) 7 schematically shows an example of the software configuration of the arithmetic device 16 according to this embodiment. The processor 161 of the arithmetic device 16 executes instructions included in the program 81 stored in the memory 162. As a result, the arithmetic device 16 according to this embodiment operates as a computer including a timing generating unit 60, an acquiring unit 61, an angle calculating unit 62, a first calculating unit 63, a second calculating unit 64, and an integrating unit 65 as software modules.

[0069] The timing generating unit 60 is configured to measure the time interval (timing) for operating the magnetic sensor 15. Electricity is supplied to the magnetic sensor 15 at the timing measured by the timing generating unit 60, and is not supplied with electricity at other times. The units 61 to 65 of the computing device 16 are driven at the timing measured by the timing generating unit 60, and are set to a standby state (e.g., stop mode) at other times. The acquiring unit 61 operates the magnetic sensor 15 at the time interval measured by the timing generating unit 60, thereby continuously acquiring measurement results (sin θ, cos θ) of the angle of the rotating hand 22 from the magnetic sensor 15. The angle computing unit 62 is configured to convert the measurement results (sin θ, cos θ) of the magnetic sensor 15 into an angle (θ).

[0070] The first calculation unit 63 is configured to calculate the number of rotations (n) of the rotary pointer 22 by detecting that the rotary pointer 22 has circulated through the divided areas (A1 to A4) formed by the division of the first condition in the angular space based on the measurement result (θ) acquired from the magnetic sensor 15. The second calculation unit 64 is configured to calculate the scale (p) indicated by the rotating hand 22 by identifying the sectional area to which the rotating hand 22 belongs from among the sectional areas (B0 to B9) formed by dividing the second condition based on the measurement result (θ) acquired from the magnetic sensor 15.

[0071] The integrating unit 65 is configured to integrate the calculation results (n, p) of the first calculating unit 63 and the second calculating unit 64. In this embodiment, the meter F is a flow meter (dry water meter), and the detector 1 is used in a 1-liter meter M1. Therefore, the integrating unit 65 may be configured to calculate the flow rate by performing the calculation of n×10+p. The calculation result obtained by the integrating unit 65 may be provided to the external computer UT via the communication device 17.

[0072] In this embodiment, each software module of the arithmetic device 16 is implemented by the processor 161. However, some or all of the software modules may be implemented by one or more dedicated processors. Each module may be implemented as a hardware module. Furthermore, with regard to the software configuration of the arithmetic device 16, modules may be omitted, replaced, or added as appropriate depending on the embodiment.

[0073] §2 Example of operation 8 is a flowchart showing an example of a processing procedure of the arithmetic device 16 according to this embodiment. The processing procedure described below is an example of an information processing method by the detector 1. However, the processing procedure described below is merely an example, and each step may be changed as much as possible. Furthermore, steps may be omitted, replaced, or added to the following processing procedure as appropriate depending on the embodiment.

[0074] (Step S101) In step S101, the processor 161 operates as the timing generator 60 and determines the time interval (T i In this embodiment, the measurement time interval (T i) is set to be shorter than the reference value. i ) may be set to satisfy at least one of the above formula 1, formula 2, and formula 3.

[0075] The passage of time may be measured by any method. In one example, the passage of time may be measured by software processing. In another example, the computing device 16 may further include a timer, and the passage of time may be measured by the timer. (T i If the time (T i ) has elapsed, the processor 161 proceeds to the next step S102.

[0076] (Steps S102 and S103) In step S102, the processor 161 operates as the acquisition unit 61 and drives the magnetic sensor 15 (i.e., supplies electricity) to acquire the measurement result (sin θ, cos θ) of the angle of the rotating needle 22 from the magnetic sensor 15. In step S103, the processor 161 operates as the angle calculation unit 62 and performs the calculation process of the above equation 6 to convert the measurement result (sin θ, cos θ) of the magnetic sensor 15 into an angle (θ). Upon acquiring the converted measurement result (θ), the processor 161 proceeds to the next step S104.

[0077] (Steps S104 to S106) In step S104, processor 161 determines where to branch the process depending on whether it is an initial operation. If it is an initial operation (i.e., the obtained measurement result is an initial value), processor 161 proceeds to step S105. On the other hand, if it is not an initial operation, processor 161 proceeds to step S106.

[0078] In step S105, the processor 161 stores the measurement result obtained in step S103 as the initial value (θ0) of the angle in the memory 162. In one example of the initial operation, the measurement result of the angle measured with respect to the rotary hand 22 pointing to the scale mark "0" may be acquired as the initial value (θ0). After storing the initial value (θ0) of the angle, the processor 161 returns the process to step S101 and executes the process from step S101 again.

[0079] On the other hand, in step S106, the processor 161 calculates the measurement result (θ t ) and the initial value of the angle (θ0). In this way, processor 161 obtains the measurement result (θ) of the angle of rotating hand 22 at the current sampling time. After obtaining the measurement result (θ), processor 161 proceeds to the next step S107. If the output angle of magnetic sensor 15 and the angle of rotating hand 22 are misaligned, the processing of steps S104 to S106 can make the output angle of magnetic sensor 15 and the angle of rotating hand 22 match.

[0080] (Step S107) In step S107, the processor 161 operates as the acquisition unit 61. That is, the processor 161 detects that the rotary hand 22 has circulated through the divided areas (A1 to A4) formed by the division of the first condition in the angular space, based on the measurement result (θ) acquired from the magnetic sensor 15. As a result, the processor 161 calculates the number of rotations (n) of the rotary hand 22.

[0081] FIG. 9A shows a schematic example of the relationship between the rotary pointer 22 and the division areas (A1 to A4) of the first condition when the rotary pointer 22 rotates in the forward direction. min / M) specifies the measurement timing so that the number of transitions of the segmented area of ​​the first condition in one sampling time is 1 or less. Therefore, as shown in FIG. 9A, during forward rotation, the difference in segmented area number (quadrant difference) between each sampling time is "1" or "0" except for the timing at which one rotation is completed. On the other hand, when transitioning from the final segmented area to the first segmented area (in this embodiment, from the fourth segmented area A4 to the first segmented area A1), the difference in segmented area number (quadrant difference) is "-(M-1)" (in this embodiment, "-3").

[0082] 9B shows a schematic example of the relationship between the rotary pointer 22 and the segmented areas (A1 to A4) of the first condition when the rotary pointer 22 rotates in the reverse direction. For the same reason as in the forward direction case, the difference in segmented area numbers (quadrant difference) between each sampling time during the reverse rotation is "-1" or "0" except for the timing at which one rotation is completed. On the other hand, when transitioning from the first segmented area to the last segmented area (in this embodiment, the first segmented area A1 to the fourth segmented area A4), the difference in segmented area numbers (quadrant difference) is "M-1" (in this embodiment, "3").

[0083] Therefore, as an example of a process for detecting the rotation of the rotary hand 22, the processor 161 may identify the sectional area to which the rotary hand 22 belongs from among the sectional areas (A1 to A4) of the first condition based on the acquired measurement result (θ). Next, the processor 161 may calculate the number difference (quadrant difference) between the sectional areas identified at the current sampling time and the previous sampling time. Then, the processor 161 may detect one rotation of the rotary hand 22 in the forward or reverse direction and count the number of rotations depending on whether the calculated number difference (quadrant difference) is "-(M-1)" or "M-1". After calculating the number of rotations (n) of the rotary hand 22, the processor 161 proceeds to the next step S108.

[0084] (Step S108) Returning to FIG. 8, in step S108, the processor 161 operates as the second calculation unit 64. That is, the processor 161 calculates the measurement result (θ) obtained from the magnetic sensor 15 as Based on this, the processor 161 identifies the segment area to which the rotary hand 22 belongs from among the segment areas (B0 to B9) formed by the division of the second condition.

[0085] In this embodiment, as illustrated in Fig. 4, the number of division areas formed by dividing the second condition may be the same as the number of scales on the gauge F. In this case, the processor 161 can directly identify the scale from the division area of ​​the second condition to which the rotary hand 22 belongs. After calculating the scale (p) indicated by the rotary hand 22, the processor 161 proceeds to the next step S109.

[0086] Note that the method for identifying the sectional area to which the rotary needle 22 belongs in steps S107 and S108 is not particularly limited and may be determined appropriately depending on the embodiment. In one example, the correspondence between the sectional areas (A1 to A4, B0 to B9) of each condition and the angle may be stored in the memory 162 as reference information. In this case, the processor 161 may identify the sectional area to which the rotary needle 22 belongs by referring to the reference information based on the acquired measurement result (θ). In another example, the correspondence may be defined as a processing condition in the program 81. In this case, the processor 161 may identify the sectional area to which the rotary needle 22 belongs by executing a calculation of the processing condition based on the acquired measurement result (θ).

[0087] (Step S109) In step S109, the processor 161 operates as the integrating unit 65 and integrates the calculation results (n, p). The integration method may be determined depending on the application of the detector 1. In this embodiment, as an example of the integration process, the processor 161 may calculate the flow rate by performing the calculation of n×10+p. After integrating the calculation results (n, p), the processor 161 proceeds to the next step S110.

[0088] (Steps S110 and S111) In step S110, processor 161 determines whether or not to transmit the calculation result (n×10+p).

[0089] As an example of the determination process, whether to transmit may be determined based on a trigger. The transmission trigger may be provided as appropriate depending on the embodiment. In one example, the transmission trigger may be set to ON in response to an external computer UT being connected to the arithmetic device 16 via wireless communication. In response, the processor 161 may determine to transmit the calculation results. On the other hand, if the external computer UT is not connected, the transmission trigger may be set to OFF, and in response, the processor 161 may determine not to transmit the calculation results.

[0090] If it is determined that the calculation result is to be transmitted, the processor 161 proceeds to the next step S111. In step S111, the processor 161 transmits the calculation result by wireless communication using the communication device 17. When the transmission is completed, the processor 161 proceeds to the next step S112. On the other hand, if it is determined that the calculation result is not to be transmitted, the processor 161 skips the processing of step S111 and proceeds to step S112.

[0091] (Step S112) In step S112, the processor 161 determines whether or not the process of calculating the number of rotations of the rotary hand 22 is to be ended.

[0092] As an example of the determination process, whether to terminate may be determined based on a trigger. The termination trigger may be provided as appropriate depending on the embodiment. In one example, the termination trigger may be set to off while no optional termination operation is performed. In response to an optional termination operation being performed, the termination trigger may be set to off. In another example, the termination trigger may be set to ON while the remaining power of the power source (e.g., battery, solar cell, etc.) exceeds a predetermined value. In response to the remaining power of the power source falling below a predetermined value, the termination trigger may be set to ON.

[0093] If the termination trigger is OFF, the processor 161 may determine not to terminate the processing. If it is determined not to terminate the processing, the processor 161 returns the processing to step S101 and executes the processing from step S101 again. In this embodiment, the calculation device 16 repeatedly executes the series of processing from step S101, thereby continuously acquiring measurement results of the angle of the rotary hand 22 from the magnetic sensor 15, and can calculate the rotation speed n and scale p of the rotary hand 22 based on the acquired measurement results.

[0094] On the other hand, in response to the termination trigger being on, the processor 161 may determine to terminate the processing. If it is determined to terminate the processing, the processor 161 terminates the processing procedure related to this operation example. After the processing procedure related to this operation example is terminated, the processor 161 may resume the processing from step S101 in response to any trigger, such as, for example, a start operation being performed, or the remaining amount of power exceeding a predetermined value and power being supplied.

[0095] [Measurement example] 10A is a diagram showing an example of the measurement result (sin θ) of the magnetic sensor 15 when the rotating needle 22 rotates 72 degrees in the forward direction in one sampling time. 11 is a diagram showing an example of the measurement result (cosθ) of the magnetic sensor 15 when the rotating hand 22 rotates forward by 72 degrees in one sampling time. 12 shows an example of the relationship between the measurement results of the magnetic sensor 15, the region of the first condition to which the rotating hand 22 belongs, and the calculation results of the arithmetic unit 16 when the rotating hand 22 rotates forward by 72 degrees at a time. FIG. 12 shows an example of the relationship between the measurement results of the magnetic sensor 15, the region of the first condition to which the rotating hand 22 belongs, and the calculation results of the arithmetic unit 16 when the rotating hand 22 rotates forward by 85 degrees at a time in one sampling time. As shown in FIGS. 10A, 10B, 11, and 12, the number of rotations (n) and the scale (p) of the rotating hand 22 can be appropriately calculated by the processing of steps S101 to S109 in both the case of rotation by 72 degrees and the case of rotation by 85 degrees.

[0096] [Features] As described above, in this embodiment, the measurement time interval (T i ) is the reference value (T min / M) specifies that the number of transitions in the division area of ​​the first condition in one sampling time is 1 or less. Since the division number of the first condition is 3 or more, the measurement time interval (T i By defining the range (A1-A4) in this manner, it is possible to prevent the rotary pointer 22 from reaching the same segmented area after one sampling time has elapsed when the rotary pointer 22 rotates in both the forward and reverse directions. In the example of FIG. 4, it is assumed that the rotary pointer 22 belongs to the first segmented area A1. In this case, the segmented area to which the rotary pointer 22 can move when rotated in the forward direction is the second segmented area A2, and the segmented area to which the rotary pointer 22 can move when rotated in the reverse direction is the fourth segmented area A4. In this way, it is possible to prevent the rotary pointer 22 from reaching the same segmented area after one sampling time has elapsed for both the forward and reverse rotations. This makes it possible to distinguish between the forward and reverse rotations of the rotary pointer 22, as exemplified in FIGS. 9A and 9B. Therefore, as shown in FIGS. 11 and 12, the number of rotations of the rotary pointer 22 can be appropriately calculated based on the rotation of the rotary pointer 22 through the segmented areas (A1 to A4) of the first condition.

[0097] In addition, the time interval between measurements (T i ) to the reference value (T min / M), the number of times the magnetic sensor 15 is driven (i.e., the processing of steps S101 to S109 is repeated) while the rotary hand 22 is staying in one of the division areas of the first condition can be reduced. . When the rotary pointer 22 rotates at the maximum speed, the measurement time interval (T i ) to the reference value (T min / M), optimally, the magnetic sensor 15 can be driven once while the rotating hand 22 belongs to each of the division areas (A1 to A4) of the first condition. By setting the number of division areas to be less than the number of scale marks, optimally, the magnetic sensor 15 can be driven less than the number of scale marks during one rotation of the rotating hand 22. That is, in this embodiment, the reference value is used as an index to reduce the number of times the magnetic sensor 15 is driven when measuring the rotation speed of the rotating hand 22. This makes it possible to lengthen the period during which the driving of the magnetic sensor 15 is turned off, as illustrated in FIGS. 10A and 10B. Therefore, according to this embodiment, it is possible to reduce energy consumption in the detector 1 that detects the rotation speed of the rotating hand 22 in the meter F.

[0098] §3 Variations Although the embodiments of the present invention have been described above in detail, the above description is merely illustrative of the present invention in every respect. It goes without saying that various improvements and modifications can be made without departing from the scope of the present invention. For example, the following modifications are possible. Note that, in the following, the same reference numerals are used for components similar to those in the above embodiment, and descriptions of the same points as those in the above embodiment are omitted where appropriate. The following modifications can be combined as appropriate.

[0099] <3.1> In the processing procedure of FIG. 8 , steps may be omitted, replaced, or added. For example, the initial angle value (θ0) may be obtained at any timing. In another example, the initial angle value (θ0) may be acquired in advance before using the detector 1. The arithmetic device 16 may store the initial angle value (θ0) in advance. In this case, the storage location of the initial angle value (θ0) may be appropriately selected depending on the embodiment. In one example, the initial angle value (θ0) may be stored in the memory 162. In another example, the initial angle value (θ0) may be stored as a set value in the program 81. Since the initial angle value (θ0) is stored in advance, the processing of steps S104 and S105 may be omitted. In yet another example, initial values ​​may also be given for the rotation speed n and the scale p. In this case, measurement of the rotation speed and the scale may start from the rotation speed n0 (initial value) and the scale p0 (initial value).

[0100] Furthermore, for example, the magnetic sensor 15 may be configured to directly output the value of the angle θ as a measurement result. In this case, the process of step S103 may be omitted in the above processing procedure. The angle calculation unit 62 may be omitted from the software configuration of the calculation device 16.

[0101] Furthermore, for example, the arithmetic device 16 may be configured to transmit the calculation results (n, p) of steps S107 and S108 as they are. In this case, in the above processing procedure, the processing of step S109 may be omitted. In step S111, the processor 161 may transmit the calculation results (n, p) of steps S107 and S108. The integration unit 65 may be omitted from the software configuration of the arithmetic device 16.

[0102] Also, for example, in the above processing procedure, the timing of executing the processes of step S107 and step S108 does not need to be limited to the example of Fig. 8. In another example, processor 161 may execute the process of step S107 after executing the process of step S108. Processor 161 may execute the process of step S107 and the process of step S108 at least partially in parallel.

[0103] Also, for example, in the above processing procedure, the processing of step S110 may be omitted. In this case, the processor 161 performs the processing up to step S109 at each sampling time. The calculation result (integrated result) may be transmitted. In another example, the processor 161 may omit the processes of steps S110 and S111, and store the calculation results up to step S109 in the memory 162. Then, the processor 161 may transmit an updated version of the calculation result stored in the memory 162 all at once. The transmission of the updated version may be performed at predetermined intervals, such as several times a day, or may be performed in response to a request from the user.

[0104] Also, for example, in step S112 in the above processing procedure, processor 161 may output an alert in response to the remaining power being less than a predetermined value. Then, processor 161 may set a termination trigger to ON in response to an operation in response to this alert.

[0105] <3.2> In the above embodiment, the communication device 17 may be omitted from the configuration of the detector 1. In this case, the calculation results of the arithmetic device 16 may be output by any method. In another example, the arithmetic device 16 may be connected to the external computer UT by wire. In this case, the calculation results of the arithmetic device 16 may be transmitted to the external computer UT by wired communication.

[0106] <3.3> In the above embodiment, the configuration related to the division of the second condition may be omitted. In another example, the calculation device 16 may be configured to calculate only the rotation speed of the rotary pointer 22. In this case, the second calculation unit 64 may be omitted from the software configuration of the calculation device 16. In yet another example, the calculation device 16 may be configured to identify the scale from the measurement result of the angle of the rotary pointer 22 using a method different from that of the above embodiment. As an example of a method of identifying the scale, the processor 161 may identify the scale directly from the measurement result (θ) of the angle of the rotary pointer 22.

[0107] <3.4> In the above embodiment, the measurement time interval (T i ) is the reference value (T min / M) specifies that the number of transitions of the segmented regions of the first condition in one sampling time is one or less. However, the number of transitions allowed in one rotation of the sampling time is not limited to this example. For example, if the number of divisions of the first condition is five or more, it is still possible to distinguish between forward and reverse transitions even if two or less transitions of the segmented regions are allowed for one rotation of the sampling time.

[0108] Here, we will explain the relationship between the number of allowed transitions and identifiability. i ) is set to allow transitions between segmented regions by a natural number equal to or greater than half the number of divisions under the first condition. For example, if the number of divisions under the first condition is 3 or 4, the number of allowed transitions is 2 or more. If the number of divisions under the first condition is 5 or 6, the number of allowed transitions is 3 or more. Under this assumption, when the rotary needle 22 rotates in both the forward and reverse directions in one sampling time from any segmented region in the division under the first condition, there is a possibility that the same segmented region will be reached from that any segmented region.

[0109] As an example, let us assume that the rotating needle 22 belongs to the first division area A1 in the division of FIG. i ) is set to allow two or more transitions, there is a possibility that the same segment area (for example, the third segment area A3 in the case of two transitions) will be reached from the first segment area A1 by both the forward and reverse rotations of one sampling time. The same applies when the number of divisions in the first condition is other than four.

[0110] That is, the time interval between measurements (T i ) is set to allow a natural number of transitions of the divided regions, which is equal to or greater than half of the number of divisions in the first condition, in one sampling time, it becomes difficult to distinguish between forward and backward transitions. i) However, if the number of transitions between partitioned regions allowed in one sampling time is set to a natural number less than half the number of divisions in the first condition, the transitions described above will not occur, and it will be possible to distinguish between forward and backward transitions. For example, if the number of divisions in the first condition is 3 or 4, the number of transitions allowed is 1 or less. If the number of divisions in the first condition is 5 or 6, the number of transitions allowed is 2 or less.

[0111] Therefore, to distinguish between forward and reverse transitions and properly calculate the number of rotations of the rotary needle 22, the time interval between measurements (T i ) may be set to satisfy the above conditions. min / M) is an example of such a condition. The timing specified by the reference value is an example of the timing at which transitions in the forward and backward directions can be distinguished. However, the measurement time interval (T i The reference value of the time interval (T i ) may be determined appropriately so as to be able to specify.

[0112] In another example, the time interval (T i ) may be set to satisfy the conditions of the above-mentioned formulas 4 and 5. In this case, the greater the number of divisions in the first condition, the greater the number of transitions between the divided regions allowed in one rotation of sampling time. Therefore, even if the number of divisions in the first condition is large, it is possible to reduce energy consumption. Therefore, when the conditions of formulas 4 and 5 are adopted as the reference values, the number of divisions in the first condition may be equal to or greater than the number of scales on the meter F.

[0113] That is, in this modification, the detector 1 may be used in an instrument F having an axis 21 and a rotary pointer 22 configured to rotate around the axis 21. The detector 1 may include a magnet 11 disposed on the rotary pointer 22, a magnetic sensor 15 configured to measure the angle of the rotary pointer 22 based on the direction of the magnetic field generated by the magnet 11, and a computing device 16. The angular space of rotation of the rotary pointer 22 may be divided according to a first condition. The number of divisions in the first condition may be three or more. The computing device 16 may be configured to continuously acquire measurement results of the angle of the rotary pointer 22 from the magnetic sensor 15 by operating the magnetic sensor 15 at time intervals that satisfy the above-described formulas 4 and 5. Furthermore, the computing device 16 may be configured to calculate the number of rotations of the rotary pointer 22 based on the acquired measurement results by detecting that the rotary pointer 22 has circulated through a partitioned region in the angular space formed by the division in accordance with the first condition. This, as in the above embodiment, reduces energy consumption in the detector 1 that detects the number of rotations of the rotary pointer 22 in the instrument F.

[0114] Other configurations of this modified example may be the same as those of the above embodiment. i ) may be set to the lower limit value given by the formulas 1 to 3 in the above embodiment. i ) may be set to satisfy at least one of the following formulas 7, 8, and 9.

[0115]

number

number

number

[0116] 1...detector, 11...magnet, 12...substrate, 15...magnetic sensor, 16...arithmetic unit, 17...communication unit, 161...processor, 162...memory, 163...input / output interface, 81...program, 91...storage medium, 60... timing generation unit, 61... acquisition unit, 62... Angle calculation section, 63... First calculation section, 64...Second calculation section, 65...Integration section, F...Instrument, D...Display section, T...Transparent cover plate, M1...1 liter meter, M10...10 liter meter, 20...scale plate, 21...axis, 22...rotating needle, A1-A4... (based on the first condition) area, B0-B9... (Second condition) division area

Claims

1. 1. A detector for use in an instrument having an axis and a rotating needle configured to rotate about the axis, comprising: a magnet disposed on the rotating needle; a magnetic sensor configured to measure the angle of the rotating needle based on the direction of the magnetic field generated by the magnet; and computing device, Equipped with The angular space of rotation of the rotary needle is divided by a first condition, the number of partitioned regions formed by the division of the first condition is three or more and is less than the number of scales of the instrument; The computing device By operating the magnetic sensor at time intervals shorter than a reference value, a measurement result of the angle of the rotating hand is continuously obtained from the magnetic sensor; and calculating the number of rotations of the rotating hand by detecting whether the rotating hand has circulated through the divided area formed by the division of the first condition in the angle space based on the acquired measurement results; It is configured as follows: the reference value is obtained by dividing the minimum rotation period of the rotary hand by the number of the partitioned areas formed by dividing the first condition. Detector.

2. The angular space of rotation of the rotary needle is further divided by a second condition in addition to the first condition, the number of partitioned regions formed by the division of the second condition is greater than the number of partitioned regions formed by the division of the first condition and corresponds to the number of scales of the instrument; the arithmetic device is further configured to calculate a scale indicated by the rotating hand by identifying a segmented area to which the rotating hand belongs among the segmented areas formed by dividing the second condition based on the measurement result acquired from the magnetic sensor. The detector of claim 1 .

3. the number of partitioned regions formed by dividing the second condition is the same as the number of scales on the instrument; 3. The detector of claim 2.

4. The time interval for operating the magnetic sensor is set to satisfy Equation 1.

4. A detector according to any one of claims 1 to 3. [Equation 1] ...(Formula 1) In addition, T ｍｉｎ indicates the minimum rotation period of the rotary needle, T ｉ indicates a time interval for operating the magnetic sensor, H indicates the number of divisions on the gauge, M indicates the number of the partitioned regions formed by dividing the first condition.

5. The time interval for operating the magnetic sensor is set to satisfy Equation 2:

4. A detector according to any one of claims 1 to 3. [Equation 2] ...(Formula 2) In addition, T ｍｉｎ indicates the minimum rotation period of the rotary needle, T ｉ indicates a time interval for operating the magnetic sensor, M indicates the number of the partitioned regions formed by dividing the first condition.

6. The time interval for operating the magnetic sensor is set to satisfy Equation 3:

4. A detector according to any one of claims 1 to 3. [Equation 3] ...(Formula 3) In addition, T ｍｉｎ indicates the minimum rotation period of the rotary needle, T ｉ indicates a time interval for operating the magnetic sensor, M represents the number of the partitioned regions formed by dividing the first condition, A natural number smaller than M is substituted for k.

7. The number of partitioned regions formed by the division under the first condition is four or less.

7. A detector according to any one of claims 1 to 6.

8. The magnet is disposed on the axis of the rotating needle.

8. A detector according to any one of claims 1 to 7.

9. The instrument further includes a transparent cover plate that covers the rotary needle. The magnetic sensor and the computing device are attached to the transparent cover plate.

9. A detector according to any one of claims 1 to 8.

10. a communication device coupled to the computing device and configured to wirelessly transmit results of the computations of the computing device; 10. A detector according to any one of claims 1 to 9.

11. The meter is a flow meter for measuring the flow rate of a liquid. Detector according to any one of claims 1 to 10.

12. 1. A detector for use in an instrument having an axis and a rotating needle configured to rotate about the axis, comprising: a magnet disposed on the rotating needle; a magnetic sensor configured to measure the angle of the rotating needle based on the direction of the magnetic field generated by the magnet; and computing device, Equipped with The angular space of rotation of the rotary needle is divided by a first condition, the number of partitioned regions formed by the division of the first condition is three or more; The computing device By operating the magnetic sensor at time intervals that satisfy the conditions of Equation 4 and Equation 5, the measurement results of the angle of the rotating needle are continuously obtained from the magnetic sensor; and calculating the number of rotations of the rotating hand by detecting whether the rotating hand has circulated through the divided area formed by the division of the first condition in the angle space based on the acquired measurement results; It is configured as follows: Detector. [Equation 4] ...(Formula 4) [Equation 5] ...(Formula 5) In addition, T ｍｉｎ indicates the minimum rotation period of the rotary needle, T ｉ indicates a time interval for operating the magnetic sensor, M indicates the number of the partitioned regions formed by dividing the first condition.

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