JP2006047120A - Noncontact variable voltmeter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a noncontact variable voltmeter capable of acquiring a linear output in a desired rotation range. <P>SOLUTION: A magnetometric sensor 60<SB>A</SB>is arranged on a position where a magnetosensitive part of the magnetometric sensor 60<SB>A</SB>is faced to the boundary position between the N-pole and the S-pole of a magnet 40 on a reference position of the circular rotatable magnet 40 having the N-pole and the S-pole, and a magnetometric sensor 60<SB>B</SB>is provided at an angle of 90° with respect to the magnetometric sensor 60<SB>A</SB>. In the range of -45° to +45°, an output from the magnetometric sensor 60<SB>A</SB>is output as it is, and in the range of +45° to +135° after the magnet 40 is rotated by +45° from the reference position, an output from the magnetometric sensor 60<SB>B</SB>is added to a held output by a limiter of the magnetometric sensor 60<SB>A</SB>and output, and thereby an output voltage changing linearly corresponding to a rotation angle in the range of 180° from -45° to +135° wherein the magnet 40 is rotated is acquired. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a contactless variable voltage device composed of a magnet and a magnetic sensor, and more particularly to a variable resistor incorporated in a stick controller or the like used as an input device for a personal computer or a game device, or a normal variable resistor. The present invention relates to a non-contact variable voltage device used for the above.

As a non-contact variable voltage generator using a magnet and a magnetic sensor, a bearing is fixed at the center of the upper part of the housing, and the operation shaft is rotatably supported by this bearing, and the magnet is integrated with the operation shaft in the operation shaft portion in the housing. A magnetic sensor that is mounted so as to rotate and a magnetic sensor is arranged opposite to the magnet and the output of the magnetic sensor is changed by a change in magnetic flux caused by the rotation of the magnet is disclosed (for example, see Patent Document 1).
Japanese Patent Laid-Open No. 11-325956

  In the conventional non-contact variable voltage device described above, the magnet and the magnetic sensor are arranged, for example, in the positional relationship shown in FIG. In FIG. 8, the circular magnet 40 is rotated in the vicinity of the magnetic sensor 60 by the operation shaft attached to the attachment hole 41. In accordance with the rotation of the magnet 40, the magnetic sensor 60 outputs a voltage corresponding to the rotation angle of the magnet 40.

  As shown in FIG. 8, the rotation position where the N pole and S pole of the magnet 40 are equidistant from the magnetic sensor 60 is 0 °, and the S pole is 90 ° in the direction approaching the magnetic sensor 60 from this 0 ° position. The rotated position is -90 °, and conversely, the position where the N pole is rotated in the direction approaching the magnetic sensor 60 from the 0 ° position is the + 90 ° rotational position. FIG. 9 shows an output waveform of the magnetic sensor 60 when the magnet 40 is rotated from a position of −90 ° to a position of + 90 ° by the operation shaft.

  As is apparent from this figure, the output voltage changes almost sinusoidally with the rotation of the operation shaft, and when the rotation angle of the variable voltage device is 0 to 180 ° (-90 ° to + 90 ° in FIG. 9), − In the rotation range of 45 ° to + 45 °, the change in output voltage is linear, but in the range of −90 ° to −45 ° and + 45 ° to + 90 °, the change in output voltage is not linear and practically 120 °. Even if it can be used in the range of (−60 ° to + 60 °), there is a problem that a linear output voltage cannot be obtained at all rotation angles of 0 ° to 180 °.

  The present invention has been made paying attention to the above-mentioned problems, and an object thereof is to provide a contactless variable voltage device capable of obtaining a linear output at a desired rotation angle wider than that in the prior art.

  The contactless variable voltage device of the present invention includes a housing, an operation shaft rotatably supported by the housing, a magnet attached to an operation shaft portion in the housing and rotating integrally with the operation shaft, and opposed to the magnet. A non-contact variable voltage device that changes the output of the magnetic sensor by changing the magnetic flux due to the rotation of the magnet, and includes a plurality of the magnetic sensors, and the magnetic sensors have a predetermined angle with respect to each other. And a summing means for summing up the outputs of the plurality of magnetic sensors, and the summing means obtains an output corresponding to the rotation of the operation shaft. The summing means here can be exemplified by an adding means, but may be a subtracting means.

  In the present invention, each magnetic sensor includes a limiter that holds and outputs the output when the absolute value of the output exceeds a predetermined value, and the limiter output can be input to the summing means.

  In the present invention, 90 ° is exemplified as the predetermined angle. In the present invention, any magnetic sensor may be used as long as it can take out a change in the strength of the magnetic field as an electric signal, and a Hall element, a magnetoresistive element [for example, a magnetic resistance sensor (MR sensor)]. Is exemplified.

  According to the present invention, a plurality of magnetic sensors are provided, and the output voltage of the variable voltage device is obtained by adding together the output voltages from which the linear characteristics of the respective magnetic sensors are obtained. Can be obtained.

  In addition, if the absolute value of each magnetic sensor output exceeds a predetermined value by the limiter of the magnetic sensor, the predetermined value is held and output, so that the influence of the non-linear part of each magnetic sensor can be reduced, and the linear change It becomes easy to obtain the output voltage.

  In addition, by setting the position shift angle between the magnetic sensors to 90 °, a linear region in the range of 90 ° can be obtained with each magnetic sensor, and by using two magnetic sensors, the linear range can be obtained in the rotation range of 180 °. An output voltage with various changes can be obtained.

  Hereinafter, the present invention will be described in more detail with reference to embodiments. FIG. 1 shows an external perspective view of a contactless variable voltage device according to an embodiment of the present invention. Further, FIG. 2 shows a cross-sectional view of the main part of the contactless variable voltage device of this embodiment, and FIG. 3A shows a side view seen from the bottom side of the housing with the shield cover removed. The viewed side view is shown in FIG.

  In the contactless variable voltage device 1 according to this embodiment, a housing is constituted by a circular case 10 having an open bottom and a shield cover 11 fitted to the bottom so as to close the bottom opening of the case 10. The case 10 has a positioning boss 12 used for positioning when the voltage device 1 is incorporated in a device that uses the voltage device 1.

  A bearing portion 20 projects from the center of the upper portion of the case 10, and the operation shaft 30 is provided near the center portion by the bearing portion 20 as an engaging portion that engages with the inner wall of the bearing portion 20 of the case 10. A hook 31, a hook 32 that protrudes from the inner end (left end) and attaches the magnet 40, and a rib 34 that engages around the magnet 40 and positions the magnet 40. The hooks 31 and 32 have moderate elasticity so that both can be displaced.

  Corresponding to the hook 31 of the operation shaft 30, a support portion (step portion) 21 that supports the operation shaft 30 by engaging with the hook 31 is provided on the inner wall of the bearing portion 20 of the case 10. A convex portion 22 is provided at the end of the bearing portion 20 in the case 10, and the convex portion 22 abuts on the stepped portion 33 of the operation shaft 30. Therefore, when the operating shaft 30 is inserted into the bearing portion 20, the hook 31 of the operating shaft 30 engages with the support portion 21 of the bearing portion 20, and the convex portion 22 of the case 10 contacts the stepped portion 33 of the operating shaft 30. Thus, the operation shaft 30 is reliably supported so as not to be detached from the bearing portion 20. A screw portion 23 for fixing the contactless variable voltage device 1 to an input device such as a stick controller with a nut is formed on the outer periphery of the bearing portion 20.

  Inside the case 10, a magnet 40 having a circular planar shape as shown in FIG. 7 is attached to the inner end of the operation shaft 30, and the magnet 40 rotates integrally with the operation shaft 30. The magnet 40 has a mounting hole 41 at the center thereof, and the hook 32 of the operating shaft 30 is inserted into the mounting hole 41 and the hook 32 engages with the peripheral edge of the mounting hole 41, so that the magnet 40 is It is integrally attached to the operation shaft 30. When assembling the operation shaft 30 to the case 10, it is only necessary to first attach the magnet 40 to the operation shaft 30 and then insert the operation shaft 30 into the bearing portion 20 from the bottom side of the case 10. .

A printed circuit board 50 is fixed to the case 10 with screws 51 inside the case 10. On one surface side of the printed circuit board 50, a magnetic sensor positioned and the magnetic sensor 60 _A, which is held by the sensor holder 61 _A, as shown in FIG. 7, the different positions of the angle of the magnetic sensor 60 _A and 90 degrees 60 and _B and the sensor holder 61 _B, are mounted and the connector 55 for external circuit connection, the other side the various constituting the circuit portion for converting the output change of the magnetic sensor 60 _a, 60 _B to the voltage change An electronic component 56 is mounted. The magnetic sensor 60 _A (60 _B) is securely fixed to the fixing hook 62 _A (62 _B) in the sensor holder 61 _A (61 _B), the hook 62 _A (62 _B) is in a hole formed in the printed circuit board 50 It is mated.

The magnetic sensor 60 _A is arranged with a slight gap around the outer periphery of the magnet 40. Magnet 40 is facing surface circular arc-shaped magnetic sensor 60 _A, also the magnet 40 is rotated, so that the distance between the opposed surface and the magnetic sensor 60 _A of the magnet 40 is maintained constant Yes. The magnetic sensor 60 _A is positioned so that when the operating shaft 30, that is, the magnet 40 is at the reference position, the magnetic sensing section faces the boundary between the N pole and the S pole of the magnet 40 (see the position shown in FIG. 7). and it has the magnetic sensors 60 _a in this state does not detect a magnetic change, not output. The magnetic sensor 60 _B is disposed at an angle of 90 degrees toward the positive rotation direction of the operation shaft 30 with respect to the magnetic sensor 60 _A around the operation shaft 30, and the relationship with the magnet 40 is related to the magnetic sensor 60 _A. It is the same as the case of. Thus, it is one of the features of the contactless variable voltage device of this embodiment that the two magnetic sensors 60 _A and 60 _B are provided and these magnetic sensors are arranged at an angle of 90 °.

The connector 55 is mounted toward the outside of the case 10 and is connected to, for example, a shielded cable. Note that the magnetic sensors 60 _A and 60 _B and the printed circuit board 50 may be separately disposed and connected to each other by lead wires. The shield cover 11 is made of a magnetic material. By surrounding the magnet 40 and the magnetic sensors 60 _A and 60 _B with the shield cover 11, the shield cover 11 is hardly affected by external magnetism, and the magnetism of the internal magnet 40 is exposed to the outside. There is less leakage.

Next, a circuit example which is a circuit connection of various electronic components 56 including the magnetic sensor of the contactless variable voltage device 1 of this embodiment will be described. FIG. 4 shows an example of a circuit when a Hall element is used as the magnetic sensor. Magnetic sensor circuit 70 _A is the signal output circuit of the magnetic sensor 60 _A, the magnetic sensor circuit 70 _B is a signal output circuit of the magnetic sensor 60 _B, the outputs of the magnetic sensor circuit 70 _A and a magnetic sensor circuit 70 _B, The signals are added by the adding circuit 71 and output. Details of the operation will be described later.

Magnetic sensor circuit 70 _A is cut and the magnetic sensor 60 _A is a Hall element, an analog amplifier IC ₁ for amplifying the voltage from the magnetic sensor 60 _A, the predetermined value or more the output of the analog amplifier IC ₁ in the positive and negative And a limiter IC ₂ for output.

In the magnetic sensor circuit 70 _A , the voltage applied between V _{CC and} V _EE is passed through the resistors R ₁ and R ₂ to pass through the magnetic sensor 60 _A that is a Hall element. If no magnetism to the magnetic sensor 60 _A, the magnetic sensor 60 _A does not generate a voltage, through the output connected to the resistor R _3, R _4, is not provided input to the analog amplifier unit IC _1. This is also the case of no magnetic force boundary between N pole and S pole of the magnet 40 to the magneto-sensitive portion of the magnetic sensor 60 _A is facing. Here, the operating shaft 30 is rotated, when the N pole approaches the magnetic sensor 60 _A, positive voltage to the output terminal of the resistor R ₄ to the connected magnetic sensor 60 _A is connected to the resistor R ₃ an output terminal side Negative voltage is generated at The output voltage of the magnetic sensor 60 _A is input to the amplifier IC ₁ , amplified by an amplification factor determined by the resistor R ₅ , and input to the limiter IC ₂ . When the N pole further approaches the magnetic sensor 60 _A and the output of the amplifier IC ₁ reaches a predetermined value, the limiter IC ₂ cuts the value beyond it, and when it reaches the predetermined value, it is held at the predetermined value thereafter. Output voltage.

Conversely, the operating shaft 30 is rotated, when the S pole approaches the magnetic sensor 60 _A, the magnetic sensor A positive voltage on the output terminal side of the resistor R ₃ connected to the magnetic sensor 60 _A is connected to the resistor R _{4 A} negative voltage is generated on the 60 _A output terminal side. The output voltage of the magnetic sensor 60 _A is input to the amplifier IC ₁ , amplified by an amplification factor determined by the resistor R ₅ , and a negative voltage is input to the limiter IC ₂ . When the S pole further approaches the magnetic sensor 60 _A and the output of the amplifier IC ₁ becomes more negative than a predetermined negative value, the limiter IC ₂ cuts the further negative amount. When the S pole is further approached, a voltage held at a predetermined value is output thereafter.

As a result of the above operation, the output voltage of the magnetic sensor circuit 70 _{A corresponds} to the normal rotation (clockwise rotation) of the operation shaft 30 as shown by the thick line in FIG. The angle changes linearly, and is held at a predetermined value of minus or plus at a minus angle of −45 ° or more and a plus angle of + 45 ° or more, respectively.

The magnetic sensor circuit 70 _B has basically the same circuit as the magnetic sensor circuit 70 _A , but the magnetic sensor 60 _B is arranged 90 ° away from the magnetic sensor 60 _{A in the} forward rotation direction. Therefore, in the magnetic sensor circuit 70 _B , the operation shaft 30 is rotated so that the position where the boundary between the N pole and the S pole of the magnet 40 faces the magnetic sensitive part of the magnetic sensor 60 _A is 0 °, and the output waveform is obtained. If it shows, it will become like S2 of FIG.5 (b). In this waveform, when the operating shaft 30 is rotated in the plus direction, the output changes linearly from the position of + 45 ° 90 ° behind the output of the magnetic sensor circuit 70 _A , and then linearly outputs up to + 135 °. Change continues.

In this embodiment, both outputs of the magnetic sensor 70 _A and the magnetic sensor circuit 70 _B are input to the adder circuit 71, the rotation start of the operation shaft 30 is set to −45 °, and then to the position of + 45 °, the magnetic sensor While the output of the circuit 70 _A rises linearly, the output of the magnetic sensor 70 _B is limited to the minus side and is held at 0 V. Therefore, only the linear change output of the magnetic sensor circuit 70 _A is output from the adder circuit 71. . Next, from the position of + 45 ° to + 135 °, the output of the magnetic sensor circuit 70 _A is limited to V _1, and only the output of the magnetic sensor circuit 70 _B changes linearly from 0 v to V ₁ . Therefore, during this time, the output of the adder circuit 71 changes linearly from V ₁ to 2V ₁ . In this way, by adding and outputting the outputs of the magnetic sensor circuit 70 _A and the magnetic sensor circuit 70 _B by the adder circuit 71, as shown in FIG. 6, the operating shaft 30 is rotated by 180 ° from −45 ° to + 135 °. In the range, a linear output voltage corresponding to the rotation angle can be obtained.

When the operation shaft 30 is rotated to the angle + 135 ° shown in FIGS. 5 and 6 and this time the operation shaft 30 is rotated in the reverse direction to + 45 °, the output of the magnetic sensor circuit 70 _A is limited to V ₁ . In contrast to the voltage, the output of the magnetic sensor circuit 70 _B changes linearly from V ₁ to 0 as shown in FIG. Therefore, the output of the adding circuit 71 during this period changes from 2V _{1 to} V ₁ shown in FIG.

Further, when the operation shaft 30 is rotated in the reverse direction from the angle + 45 ° to −45 °, the output of the magnetic sensor 70 _A decreases linearly from V ₁ to 0. On the other hand, the output of the magnetic sensor circuit 70 _B remains limited to 0v. Therefore, the output of the adder circuit 71 during this period changes from V _{1 to} 0 in FIG.

  As described above, in the contactless variable voltage device 1 of this embodiment, when the operation shaft 30 is normally rotated from −45 ° to + 135 °, or conversely from + 135 ° to −45 °, the operation shaft 30 is rotated. An output voltage corresponding to each rotational position can be obtained linearly.

  In the above embodiment, the case where two magnetic sensors are arranged 90 ° apart and linear output characteristics are obtained in the rotation range of 0 to 180 ° has been described. However, as another embodiment, three magnetic sensors are provided. The sensors may be arranged with a 60 ° shift, and linear outputs at a rotation angle of 60 ° obtained by the respective magnetic sensors may be added to obtain a linear output characteristic within a rotation range of 0 to 180 °. Further, the four magnetic sensors are arranged with a 45 ° offset, and linear outputs are added at a rotation angle of 45 ° obtained by each of the magnetic sensors so that a linear output characteristic is obtained in a rotation range of 0 to 180 °. good.

1 is an external perspective view of a contactless variable voltage device according to an embodiment of the present invention. It is principal part sectional drawing of the same contactless variable voltage device. It is the side part (a) seen from the housing bottom face side in the state which removed the shield cover of the non-contact variable voltage device of Drawing 1, and the side view (b) seen from the operation axis side. It is a figure which shows the circuit example of the magnetic sensor circuit containing the magnetic sensor of the contactless variable voltage device of the embodiment. It is a figure which shows the output waveform of the magnetic sensor circuit. It is a figure which shows the relationship between the rotation position of the operating shaft of the same embodiment non-contact variable voltage device, and an output voltage. It is a figure which shows the installation position of the magnet and magnetic sensor of the contactless variable voltage device of the embodiment. It is a figure which shows the installation position of the magnet and magnetic sensor of the conventional non-contact variable voltage device. It is a figure which shows the relationship between the rotation position of the operating shaft of the conventional non-contact variable voltage device, and the output of a magnetic sensor.

Explanation of symbols

1 Non-contact variable voltage device 10 Case (housing)
11 Shield cover (housing)
30 Operation shaft 40 Magnet 60 _A , 60 _B Magnetic sensor 70 _A , 70 _B Magnetic sensor circuit IC ₁ Analog amplifier IC ₂ Limiter 71 Adder circuit

Claims (3)

A housing, an operation shaft that is rotatably supported by the housing, a magnet that is attached to an operation shaft portion in the housing and rotates integrally with the operation shaft, and a magnetic sensor that is disposed to face the magnet. In the non-contact variable voltage device that changes the output of the magnetic sensor by the change of magnetic flux due to the rotation of the magnet
The magnetic sensor includes a plurality of magnetic sensors, each magnetic sensor is disposed at a predetermined angle, and includes a summing means for summing up the outputs of the plurality of magnetic sensors, and the summing means enables rotation of the operation shaft. A non-contact variable voltage device characterized by obtaining a corresponding output.   2. The magnetic sensor according to claim 1, further comprising a limiter that holds and outputs the absolute value of the output when the absolute value of the output exceeds a predetermined value, and inputs the limiter output to the summing unit. Non-contact variable voltage device.   The contactless variable voltage device according to claim 1 or 2, wherein the predetermined angle between the magnetic sensors is 90 °.

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