JP3604472B2 - Multi-point magnetic field measurement device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an apparatus for performing multipoint magnetic field measurement by combining a plurality of magnetic sensor ICs.
[0002]
[Prior art]
The magnetic sensor and IC are packaged in a single package, or a multi-point magnetic sensor IC that combines multiple magnetic sensor ICs is used to measure the magnetic field at multiple points. It is widely used for detecting various positions of industrial equipment such as looms, automobiles, and home appliances, home automation such as opening and closing detection of blind shutters, and home security such as detection of window breakage. Conventionally, magnetic sensor ICs are arranged for each measurement point by the number of measurement points. FIG. 6 shows a configuration of a conventional multipoint magnetic field measuring apparatus. A plurality of magnetic sensor ICs ₁ arranged at positions a _{11 to} a _mn respectively have an input terminal 2, an output terminal 3 and a ground terminal 4, and magnetic sensor ICs a _{11 to am 1} ,... A _{1n to} a _mn. The input terminal 2 is connected to a common input wiring 5 to receive an input voltage from the data processing device 8, and the ground terminal 4 is also connected to the common ground wiring 7. However, the outputs of the magnetic sensor ICs are routed to the output wiring 6 for each IC and collected and processed by the data processing device 8 having various arithmetic functions, so that the magnetic field measurement or the position state detection at each measurement point is performed. ing. The number of wirings is m × n + 2. However, these devices that require magnetic field measurement have recently become larger and more complex due to energy saving or optimal control, and the number of measurement points that require magnetic field measurement has also increased significantly. As a result, the number of wirings of the output of the magnetic sensor IC that are routed to the data processing device for each magnetic sensor IC has been increasing, and in addition to the increase in weight, which is a problem in automobiles and the like, the wiring is complicated. However, problems such as a decrease in reliability and an increase in costs for assembling the apparatus have become significant.
[0003]
[Problems to be solved by the invention]
The present invention relates to an apparatus for measuring a magnetic field at multiple points by combining a large number of magnetic sensor ICs. The number of output wires of the sensor IC is reduced, thereby reducing the reliability of the device due to the increase in the number of measurement points and the reliability of the device due to the increase in the number of measurement points. It is an object of the present invention to provide a multi-point magnetic field measurement device having a simple configuration that has been solved.
[0004]
[Means for Solving the Problems]
Multipoint magnetic field measuring apparatus according to the present invention, by combining a plurality of holes IC, position _{a xy (x = 1~m, y} = 1~n) in multipoint magnetic field measuring device for measuring the magnetic flux density of, m × n And the input terminals of the Hall ICs connected to the input wirings divided into n wirings common to each of the y positions at the positions a _xy arranged in the _mxn. through the respective output terminals of the Hall IC, which is connected to the output line which is divided into m pieces of wires is common for each of the m × placement position a _xy in n x, the entering-force interconnect the input voltage is sequentially swept applied to the entering force terminals by dividing time Te, the data processing means to obtain an output voltage from Kide output terminal before in synchronization with the sweep application of the input voltage via a pre Kide force lines It is characterized by having.
[0005]
Also features Hall IC der Rukoto having a function in which a plurality of Hall IC converts the output of the TTL level corresponding to the output voltage set threshold of the Hall element, respectively.
[0006]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a multipoint magnetic field measuring apparatus according to the present invention will be described with reference to FIG.
[0007]
A magnetic sensor IC 1 having a three-terminal configuration having a power input terminal 2, an output terminal 3, and a ground terminal 4 is disposed at a measurement position a _xy (a _{11 to am 1} ... A _{1n to} a _mn ). Input terminal of the magnetic sensor IC position _{a xy} for x = 1 to m having the same value of y, _i.e., the input of the magnetic sensor IC1 input terminal _2, a 12 _{~a m2} of the magnetic sensor IC1 of a 11 _{~a m1} The input terminals 2 of the magnetic sensor IC _{1 of the} terminals 2,... A _{1n to} a _mn are respectively connected to the input wiring 5 divided into n wirings common to x = 1 to m, and similarly the same. output terminals of the magnetic sensor IC position _{a xy} of y = 1 to n having a value of x, _i.e., the output terminal of the output terminal _3, a 21 _{~a 2n} magnetic sensor IC1 of the magnetic sensor IC1 of a 11 _{~a 1n} The output terminals 3 of the magnetic sensor ICs ₁ ... An _{1 to} a _mn are connected to output wirings 6 divided into m wirings common to y = 1 to n, respectively. Ground end 4 is connected to a common ground wiring 7. The (m + n + 1) wires routed from each measurement point are connected to a data processing device 8 having an arithmetic function.
[0008]
As shown in FIG. 2, the data processing device 8 having the arithmetic function performs the time division through the n divided input wirings common to each of x = 1 to m at the position a _xy and performs time division to set the m at the position of y = 1. The input voltage Vcc is sequentially swept to the input terminals of the magnetic sensor ICs at the position of y = 2, the input terminals of the m magnetic sensor ICs at the position of y = 2,... On the other hand, as shown in FIG. 3, in synchronization with the application of the input voltage, the output signals of the magnetic sensor IC are sequentially output from the m divided output wirings common to the positions a _xy at every y = 1 to n. Receive and determine Vout. With the configuration as described above, the multi-point magnetic field measurement apparatus of the present invention can measure all magnetic fields at the measurement points _axy by time division. The connection of the input terminal and the output terminal is changed, and each input terminal is connected to the input wiring 5 divided into m wirings common to each of the positions a _xy at y = 1 to n, and each output terminal is connected to each position. It is the same even if it is connected to the output wiring 6 divided into n wirings common to each of x = 1 to m of a _xy .
[0009]
It should be noted here that x and y of the position a _xy do not merely indicate a position on a rectangular coordinate on a two-dimensional plane. The position a _xy can indicate a position on a curved surface, a position on oblique coordinates, or a position on one-dimensional coordinates. x and y may be considered to be used for grouping magnetic sensor ICs. FIG. 4 shows a configuration in which the magnetic sensor ICs are arranged at nine positions x _{11 to} x ₃₃ on a straight line. The input terminals of the magnetic sensor ICs arranged at the positions x ₁₁ , x ₂₁ , x ₃₁ , the input terminals of the magnetic sensor ICs arranged at the positions x ₁₂ , x ₂₂ , x ₃₂ and the positions x ₁₃ , x ₂₃ , x ₃₃ . The input terminals of the arranged magnetic sensor ICs are connected to the respective input wirings divided into three common wirings. On the other hand, the input terminals of the magnetic sensor ICs arranged at the positions x ₁₁ , x ₁₂ , x ₁₃ , the input terminals of the magnetic sensor ICs arranged at the positions x ₂₁ , x ₂₂ , x ₂₃ and the positions x ₃₁ , x ₃₂ , x An output terminal of the magnetic sensor IC arranged at ₃₃ is connected to each of the output wirings divided into three common wirings.
[0010]
As shown in FIG. 1, the magnetic sensor IC of y = 1 is changed from the magnetic sensor IC of y = 1 by time division via input wiring divided into n wirings common to x = 1 to m at the position a _xy. The sweep speed at which the voltage is applied by sweeping sequentially to the sensor IC may be set at the time resolution required for the multipoint magnetic field measuring device. However, the faster the sweep speed, the better, so it is close to the limit that the magnetic sensor IC can follow. It is possible to set
[0011]
In the multipoint magnetic field measuring apparatus according to the present invention, the output signals of the n magnetic sensor ICs are stably obtained at the terminals of the m output wirings common to the positions a _xy at y = 1 to n. It is also preferable to provide a buffer circuit for the purpose.
[0012]
The magnetic sensor IC used in the multipoint magnetic field measuring apparatus of the present invention preferably has a function of converting the output voltage of the magnetic sensor into an output of a TTL level corresponding to a set threshold value. If so, it may be a single package as shown in FIG. 1 or a module composed of several parts. In particular, a single-package one is most suitable in terms of a simple configuration of a multi-point magnetic field measuring apparatus. The magnetic sensor used in the magnetic sensor IC may be any element such as a Hall element, a semiconductor magnetoresistive element, a ferromagnetic magnetoresistive element, and a coil, as long as it can measure a magnetic field, but can measure a static magnetic field. From the viewpoint, a Hall element, a semiconductor magnetoresistive element, and a ferromagnetic magnetoresistive element are more preferable, and among them, a Hall element widely used as a magnetic sensor is optimal from the viewpoint of cost. Furthermore, when an IC using a Hall element is used as the magnetic sensor IC, any of an InSb Hall element, an InAs Hall element, a GaAs Hall element, and a Si Hall element can be used as the Hall element. In particular, an InSb Hall element is optimal from the viewpoint that highly sensitive magnetic field measurement is possible.
[0013]
【Example】
Hereinafter, the multipoint magnetic field measuring apparatus of the present invention will be described in detail with reference to examples, but the present invention is not limited to the examples.
[0014]
As a magnetic sensor IC, a 5 × 6 Hall IC array as shown in FIG. 1 was manufactured using a Hall IC having a three-terminal configuration in which a high-sensitivity InSb Hall element and an IC were incorporated in a single package by a hybrid structure. Position a _xy for x = divided commonly become six wires per 1-5 input lines, common to become five output lines, divided into wired for each position a _xy of y = 1 to 6, a ground wire Was connected to a data processor. The Hall IC uses an element of a one-sided magnetic field operation type as shown in FIG. 5, the power supply voltage Vcc is set to 5 V, the threshold magnetic flux density Bop at which the output becomes a low level of about 0 V is 20 mT, and the output is a high level of about 5 V The magnetic flux density Brp having a threshold value of 15 mT was used. 5 1 element of the measuring point a ₁₁ in the Hall IC array × 6 only paste the magnet, and the state where the output is added 20mT larger magnetic field is the magnetic flux density Bop threshold of approximately 0V. In this state, the sweep speed of the power supply voltage Vcc that is sweep-applied by time division to input wires divided into six wires common to x = 1 to 5 at the position a _xy is changed, and the state of the magnetic field is determined by data processing. We checked whether we could judge. As a result, even by increasing the sweep speed to 50 kHz, only when the power supply voltage Vcc is applied to the input lines of a _x1, confirmed that it is possible to determine as about 0V output from the output line of a _1y is low did it.
[0015]
【The invention's effect】
As described above, the multipoint magnetic field measuring apparatus of the present invention can greatly reduce the number of Hall IC wirings required by the number of measurement points as compared with the conventional example. Specifically, the number of wirings, which conventionally required at least m × n + 2 wirings for an m × n Hall IC array, could be reduced to m + n + 1. Needless to say, this effect becomes more significant as the number of measurement points increases. 2. Description of the Related Art An apparatus for measuring a magnetic field at multiple points by combining a large number of Hall ICs has been widely used as a position state detecting apparatus in combination with a magnet of a moving part of an object to be measured. In recent years, these devices have become larger and more complex from the perspective of energy saving and optimal control, and the number of measurement points requiring magnetic field measurement tends to increase significantly. The multipoint magnetic field measuring apparatus of the present invention reduces the number of output wirings of the Hall IC that are routed to the data processing device for each Hall IC, and as a result, the reliability of the apparatus is reduced due to the complicated wiring and the assembly of the apparatus is difficult. This solves problems such as an increase in the cost of the device, and achieves high mass productivity with an innovative and simple configuration. In the future, various types of equipment and devices will become more sophisticated and complicated, and as a result, the number of measurement points for which magnetic field measurement is required is expected to further increase. The benefits are great and immeasurable.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of an example of a multipoint magnetic field measuring apparatus according to the present invention.
FIG. 2 is a diagram illustrating sweep application of an input voltage used in the multipoint magnetic field measuring apparatus of the present invention.
FIG. 3 is a diagram illustrating a method of determining the presence or absence of a magnetic field used in the multipoint magnetic field measurement device of the present invention.
FIG. 4 is a diagram showing a configuration of another example of the multipoint magnetic field measurement device of the present invention.
FIG. 5 is a diagram showing an operation of a Hall IC used as a magnetic sensor IC in the embodiment of the multipoint magnetic field measuring apparatus of the present invention.
FIG. 6 is a diagram showing a configuration of a conventional multipoint magnetic field measuring apparatus.
[Explanation of symbols]
1 Magnetic sensor IC
2 Input Terminal of Magnetic Sensor IC 3 Output Terminal of Magnetic Sensor IC 4 Ground Terminal of Magnetic Sensor IC 5 Input Wiring 6 Output Wiring 7 Ground Wiring 8 Position of Data _{Processor axy} Measurement Point

Claims (2)

In a multi-point magnetic field measuring apparatus that measures a magnetic flux density at a position a _xy (x = 1 to m, y = 1 to n) by combining a plurality of Hall ICs,
a plurality of Hall ICs arranged in mxn,
An input terminal of each of the Hall ICs connected to an input wiring divided into n wirings common to every y at a position a _xy arranged in the m × n ;
An output terminal of each of the Hall ICs connected to an output wiring divided into m wirings common to each x of the position a _xy arranged in the m × n ,
Sequentially sweeping the input voltage applied to the entering force terminal by time division through the entering-force interconnect, the output voltage from the previous Kide output terminal in synchronization with the sweep application of the input voltage via a pre Kide force lines And a data processing means for obtaining the following. Multipoint magnetic field measuring apparatus according to claim 1, wherein said plurality of Hall IC is a Hall IC having a function of converting the output of the TTL level corresponding to the output voltage set threshold of the Hall element, respectively .

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