JP2008145392A - Position detector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a position detector capable of detecting a plurality of positions, and that has flexibility in its installation location. <P>SOLUTION: Signal lines Q1-Q4 are formed of wiring patterns, each having a different combination as to whether the position is on an electromagnetic coupling position by each of detection positions A-G. A detection line S1 is connected to a detection section 10. A sensor unit 9 has detecting coils C1, C2 and a signal transmission coil CT connected thereto. When the signal lines are AC-driven by a drive section 2 and a unit 9 is placed on the signal lines, the detecting coils C1, C2 pick up AC signals by a combination of the signal lines corresponding to the detection position; a detection line is AC-driven via the signal transmission coil; and then the detection section detects the detection position where the sensor unit is placed based on the waveform. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a position detection device that performs mechanical position detection and length / distance measurement, and in particular applies one of the principle of electromagnetic induction to connect one of a signal line and a coil that are relatively movable. The present invention relates to a position detection device that performs AC driving, extracts an AC signal from the other, and determines the position and the like based on the waveform.

In the case where the mechanical position is detected and the length is electrically measured, conventionally, the required position is generally detected by directly turning on / off the mechanical contact. For example, Patent Document 1 below discloses an invention relating to a liquid level gauge that detects a liquid level by providing a magnet in a float that moves up and down as the liquid level rises and falls, and opening and closing a contact of a reed switch according to the position variation of the magnet. It is disclosed.
Japanese Patent Laid-Open No. 2003-214928

  However, it has been difficult to detect a plurality of positions with a single device in the method of detecting a necessary position by ON / OFF of a direct mechanical contact as described above. Therefore, as a method for detecting a plurality of positions, a method has been proposed in which a plurality of position codes of different objects are printed and read by an optical sensor. However, in this method, the influence of external light on the optical sensor or the object is also proposed. Since the possibility of reading errors is high due to dirt on the printed code and adhesion of dust, the installation environment has been limited.

  Therefore, the present invention can detect a plurality of positions with a single device and is not easily affected by the influence of external light or environmental conditions, so that the installation location is highly flexible and can be used, for example, outdoors or underwater. An object of the present invention is to provide such a position detection device.

The position detection device according to claim 1 is a plurality of electrically independent wires arranged in the first direction and extending in the second direction, and the electromagnetic coupling positions of the wires are in the first direction. And a plurality of detection positions are set along the second direction, and each of the detection positions has a different combination of whether or not each of the wirings is at the electromagnetic coupling position. A plurality of signal lines formed in a pattern;
An electromagnetic having a plurality of coils which are provided so as to be relatively movable along the second direction of the signal line and are set at the electromagnetic coupling positions of the signal lines when arranged at the detection positions. A coupling part;
A drive unit that AC drives each of the plurality of signal lines or the coils of the electromagnetic coupling unit;
When the plurality of signal lines or the coils of the electromagnetic coupling unit are AC driven by the driving means, induction is performed on the coils of the electromagnetic coupling unit or the signal lines by electromagnetic induction at the electromagnetic coupling positions. A detection unit that detects an AC signal to be detected and detects a position of the electromagnetic coupling unit in the second direction of the signal line;
It is characterized by having.

The position detection device according to claim 2 is the position detection device according to claim 1,
The signal lines are electrically independent from each other, arranged in the first direction so as to be adjacent to the signal lines, extend in the second direction, and are defined in the first direction at the plurality of detection positions. Formed with a wiring pattern to be arranged at the electromagnetic coupling position, further comprising a detection line connected to the detection unit,
The plurality of coils of the electromagnetic coupling unit are detection coils in which alternating current is induced by alternating current flowing through the signal lines at the electromagnetic coupling positions when the coils are arranged at the detection positions of the signal lines.
The electromagnetic coupling unit further includes a signal carrying coil set to the detection line when arranged at each detection position, and the detection coil is connected in series to the signal carrying coil,
When the driving means drives the signal line with alternating current, an alternating current is induced in the detection coil in the electromagnetic coupling portion arranged at any of the detection positions of the signal line, and this alternating current flows to the signal carrier coil. A detection signal is generated on the detection line, and the detection unit detects the detection signal to detect in which detection position of the signal line the electromagnetic coupling unit is located. .

The position detection device according to claim 3 is the position detection device according to claim 1,
The drive unit, the electromagnetic coupling unit that is AC-driven by the drive unit, and a winding mechanism that is provided with the signal line and that allows a sheet having the second direction as a longitudinal direction to be taken in and out through the electromagnetic coupling unit. Has a body provided with
The detection unit for detecting the feeding length of the sheet from the waveform of alternating current generated in the signal line is provided at the tip of the sheet,
The detection means detects the alternating current induced in the signal line of the sheet by the drive means AC driving the coil of the electromagnetic coupling unit, so that any detection position of the signal line of the sheet is the It is characterized by detecting whether the sheet is located at the electromagnetic coupling portion and detecting the length of the sheet pulled out from the main body.

The position detection device according to claim 4 is the position detection device according to claim 1,
The plurality of signal lines are each formed in a closed loop shape on a sheet having the second direction as a longitudinal direction, and one side thereof along the second direction is formed by the wiring pattern and along the second direction. The other side is formed so as to be parallel to the second direction at a certain interval at the detection position on the one side,
The plurality of coils of the electromagnetic coupling unit are connected to the detection unit, and when arranged at the respective detection positions of the signal line, alternating current flows through the respective signal lines at the respective electromagnetic coupling positions. Is a detection coil that is induced,
The electromagnetic coupling unit is connected to the driving unit, and drives the signal line with an alternating current by an alternating current provided from the driving unit when the electromagnetic coupling unit is disposed at each of the detection positions on the other side of the signal line. A coil is further provided,
When the drive means AC drives the drive coil of the electromagnetic coupling unit, an alternating current is induced in the signal line of the sheet, and this alternating current induces an alternating current in the detection coil of the electromagnetic coupling unit. By detecting by the detection unit, it is detected which detection position of the signal line of the sheet the electromagnetic coupling unit is set.

The position detection device according to claim 5 is the position detection device according to claim 1,
The alternating current given to the signal line or the coil by the drive unit is an intermittent signal, and the detection unit detects a relative position of the signal line and the electromagnetic coupling unit in the second direction by a combination of the intermittent signals. It is characterized by that.

  According to the position detection device of the first aspect, when a plurality of signal lines are AC driven by the driving means, an AC signal is induced by electromagnetic induction in the coil of the electromagnetic coupling unit. Can be detected. Alternatively, if the coil of the electromagnetic coupling unit is AC driven by the driving means, an AC signal is induced by electromagnetic induction on the plurality of signal lines, and this can be detected by the detection unit. Here, since the AC signal detected by the detection unit has a waveform corresponding to a different wiring pattern for each detection position of the signal line where the electromagnetic coupling unit is arranged, a plurality of detection positions set for the signal line Which of the electromagnetic coupling portions is present can be determined from this waveform, and the relative position of the electromagnetic coupling portion to the signal line can be detected.

  According to the position detection apparatus of the second aspect, when a plurality of signal lines are AC driven by the driving means, an AC signal is induced by electromagnetic induction in the detection coil of the electromagnetic coupling unit. The AC signal induced in the detection coil is applied to the signal carrier coil of the electromagnetic coupling unit to generate an AC signal on the detection line, and this AC signal is detected by the detection unit. Here, since the AC signal detected by the detection unit has a waveform corresponding to a different wiring pattern for each detection position of the signal line where the electromagnetic coupling unit is arranged, a plurality of detection positions set for the signal line Which of the electromagnetic coupling portions is present can be determined from this waveform, and the relative position of the electromagnetic coupling portion to the signal line can be detected.

  For example, when the position detection device according to claim 2 is applied to a liquid level gauge, the second direction of the signal line is set to the vertical direction in which the liquid level moves, and the electromagnetic coupling unit is provided in the float. If the liquid level can be moved up and down along the signal line as the liquid level rises and falls, the liquid level moves up and down, the float moves, and if the detection position of the signal line facing the electromagnetic coupling part on the float changes, the detection Since the part can detect the detection position from the waveform of the AC signal flowing in the detection line, the position of the liquid level can be known.

  According to the position detection device of the third aspect, if the electromagnetic drive unit is AC driven by the driving means in a state where the sheet is pulled out from the winding mechanism by an arbitrary length, the signal line is AC driven by electromagnetic induction. A signal is induced, and the AC signal is detected by a detection unit provided at the leading end of the drawn sheet. Here, since the AC signal detected by the detection unit has a waveform corresponding to a different wiring pattern for each detection position of the signal line of the sheet facing the electromagnetic coupling unit, a plurality of signals set in the signal line It can be determined from the waveform which of the detection positions and the electromagnetic coupling portion face each other, and it can be determined how long the sheet has been pulled out from the winding mechanism.

  For example, when the position detection device according to claim 3 is applied to length measurement, a detection unit provided with display means on the front end of the sheet that can display the detection position of the sheet or the sheet drawing length corresponding thereto. It is possible to measure the length from the measurement starting point to the sheet leading edge by providing the main body at the measurement starting point and pulling out the sheet in the measuring direction and observing the display on the display means and stopping the sheet pulling out. it can.

  According to the position detection device of the fourth aspect, the sheet is laid on the object to be measured, the electromagnetic coupling portion is moved along the longitudinal direction of the sheet, and is stopped when the sheet is moved by a desired distance. In this state, if the drive unit of the electromagnetic drive unit is AC driven by the drive means, an AC signal is induced on the signal line by electromagnetic induction, and this AC signal induces an AC signal in the detection coil of the electromagnetic drive unit. A signal is detected by the detection unit. Here, since the AC signal detected by the detection unit has a waveform corresponding to a different wiring pattern for each detection position of the signal line of the sheet facing the electromagnetic coupling unit, a plurality of signals set in the signal line Which of the detection positions and the electromagnetic coupling portion face each other can be determined from the waveform, and which position in the longitudinal direction of the sheet can be determined.

  For example, when the position detection device according to claim 4 is applied to the length measurement, the sheet is placed on the measurement target (for example, on the ground such as the ground), and the electromagnetic coupling is performed while operating the drive unit and the detection unit. If the electromagnetic coupling part is stopped at a desired position while moving the part along the longitudinal direction of the sheet (along the second direction of the measurement line) and checking the detection result of the detection part, From the detection result of the detection unit indicating the movement amount, a desired movement length (a predetermined distance from the reference position) of the electromagnetic coupling unit can be obtained.

  According to the position detection device of the fifth aspect, in the effects of the above-described configurations, the alternating current given to the signal line or the coil is an intermittent signal, so that each detection position of the signal line where the electromagnetic coupling unit is arranged A position detection signal can be obtained as a signal having a waveform corresponding to the wiring pattern unique to the. Increasing the number of signal lines or the number of coils of the electromagnetic coupling unit corresponding to the number of signal lines can increase the detection positions that can be identified by the waveform.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention which are considered best by patent applicants at the time of filing to implement the present invention will be described with reference to FIGS.
1. First embodiment (first example, FIGS. 1 to 5)
FIG. 1 is a block diagram illustrating a configuration of the position detection device of the first example, FIG. 2 is a cross-sectional view of a sensor unit as an electromagnetic coupling unit in the first example, and FIG. 3 is a signal line in the first example. FIG. 4 is a waveform diagram showing a drive waveform and a detection waveform in the first example, and FIG. 5 is a more specific application of the first example. It is a perspective view which shows an example.

(1) Configuration As shown in FIG. 1, the position detection device 1 using electromagnetic induction in the first example includes signal lines Q1 to Q4 which are a plurality of electrically independent wirings (four in this example). Have. These signal lines Q <b> 1 to Q <b> 4 are arranged in a direction (first direction) orthogonal to the lines, and are extended in the longitudinal direction (second direction). It is connected and is driven by an alternating current by the drive unit 2. Then, as shown in FIG. 2, these signal lines Q1 to Q4 are sandwiched between insulating sheet materials, and are sheets (flexible sheets) that are moisture-proof or waterproof and flexible flaky parts. Pattern substrate) 3.

  As shown in FIG. 1, the drive unit 2 includes a power source 4 that converts power supplied from a commercial power source or a battery into a constant voltage, an oscillation circuit 5 that generates a reference signal for controlling the circuit, and an oscillation circuit. A frequency dividing circuit 6 that converts and divides the signal 5 into a required signal, a control circuit 7 that generates a signal for controlling the operation to the signal lines Q1 to Q4, and a power source 4 by a control signal from the control circuit 7 And a drive circuit 8 for supplying current from the signal lines Q1 to Q4.

  From the drive circuit 8, a signal serving as a measurement reference is output to signal lines Q1 to Q4 which are electrically independent wirings. Of the signal lines Q1 to Q4, a portion in the range designated as “coding region” in FIG. 1 is a movable range of the sensor unit 9 which is an electromagnetic coupling portion having a coil, and the signal line is coded. In the area, a special wiring pattern for forming position data is formed based on the positional relationship with the sensor unit 9 (details will be described later with reference to FIG. 3).

  As shown in FIG. 1, in the coding region of the signal lines Q1 to Q4, one detection line S1 is routed in a loop along the signal lines Q1 to Q4, and both ends of the detection lines S1 are detection units. 10, an AC signal induced in the detection line S <b> 1 can be detected by the detection unit 10. This detection line S1 is a detection signal for detecting the position of the sensor unit 9 arranged along the signal lines Q1 to Q4, and a signal obtained selectively by the sensor unit 9 from the signal lines Q1 to Q4 in the coding region. It is a wiring for transmitting to the detection unit 10.

  As shown in FIG. 1, the detection unit 10 to which the detection line S1 is connected includes an amplifier 11 that amplifies the signal of the detection line S1, a sensor unit based on the signals of the signal lines Q1 to Q4 that are reference signals and the signal from S1. 9 comprises an arithmetic circuit 12 for calculating the position 9 and a display 13 for displaying the result. In addition, it is good also as providing the external device controlled by the signal which shows the position of the sensor unit 9 which the arithmetic circuit 12 calculated in addition to providing the display 13 instead of the display 13.

Then, when the sensor unit 9 is disposed at an arbitrary position within the range of the coding area in which the signal lines Q1 to Q4 are special wiring patterns, and the driving unit 2 drives the signal lines Q1 to Q4, the sensor The unit 9 spreads the signals of the signal lines Q1 to Q4 in different combinations for each position, induces alternating current of the waveform based on this signal to the detection line S1, and this is detected by the detection unit 10, so The position of the sensor unit 9 is detected.
Regarding the mechanism of position detection by such a sensor unit 9, the structure of the sensor unit 9 and the wiring patterns of the signal lines Q1 to Q4 will be described in detail below.

  As shown in FIG. 2, the sensor unit 9 has three coils C1, C2, and CT in which wires are wound around three U-shaped magnetic bodies 15, respectively. The whole is formed as a single component having a moisture-proof and waterproof structure molded by a molding material 14 such as a resin so that a concave portion corresponding to the concave portion appears in the outer shape.

  Of the three coils of the sensor unit 9, two are detection coils C1 and C2, and when an alternating current flows through the signal lines Q1 to Q4 passing between the U-shaped portions of the magnetic body 15, An alternating current is induced by electromagnetic inductive coupling. One is a signal carrying coil CT, which is connected in series to the two detection coils C1 and C2, respectively, and transmits an alternating current generated in the two detection coils C1 and C2 to the detection line S1 by electromagnetic induction coupling. . In the first example, one detection coil C1 and the other detection coil C2 are wound in opposite directions, and the wires constituting the coils C1 and C2 are wound around the magnetic body 15 and the signal carrying coil CT. Is configured.

The position of the signal line Q1 to Q4 in the coding area of the signal line Q1 to Q4 where the sensor unit 9 is arranged to detect the position of the sensor unit 9 is the position with the sensor unit 9. Explain the relationship.
As shown in FIG. 3, in the signal lines Q1 to Q4 arranged in the coding area, the electromagnetic coupling positions where the electromagnetic coupling with the detection coils C1 and C2 of the sensor unit 9 is possible are arranged in parallel with each other ( The first direction (lateral direction in FIG. 3) is defined. This corresponds to a position where each of the detection coils C1 and C2 of the sensor unit 9 receives the signal lines Q1 to Q4. A plurality of detection positions A to G are set at predetermined intervals along the extending direction of each signal line Q1 to Q4 (second direction, vertical direction in FIG. 3), and each of the signal lines Q1 to Q4 is For each detection position, the four signal lines Q1 to Q4 are formed in a special wiring pattern bent into a rectangle so that the combination of whether or not each is at the electromagnetic coupling position is different. That is, when the sensor unit 9 is arranged at each detection position, the combination of the types of the signal lines Q1 to Q4 electromagnetically coupled to the two detection coils C1 and C2 of the sensor unit 9 is different for each detection position. Become. For example, in FIG. 3, the sensor unit 9 is at the detection position B. In this case, the detection coil C1 is electromagnetically coupled only to the signal line Q2, and the detection coil C2 is not electromagnetically coupled to any signal line Q2.

  As described above, the signal lines Q1 to Q4 are arranged so as to induce a combination signal necessary for detection of the detection position in the detection coils C1 and C2 at the detection position where the movable sensor unit 9 is arranged. Has been. Such an actual pattern of the signal lines Q1 to Q4 is specifically determined in consideration of the position and interval of the concave portion of the magnetic body 15 of the detection coils C1 and C2 in the sensor unit 9.

  As shown in FIG. 3, the detection line S <b> 1 in the coding region is configured by a sawtooth wiring pattern so as to exist at the electromagnetic coupling position only at the detection position. That is, the detection line S1 is arranged so as to come to the position of the magnetic body 15 of the signal carrier coil CT only at a position where position detection is performed. Therefore, only when the sensor unit 9 is disposed at any detection position, the detection line can be electromagnetically coupled to the signal carrying coil CT of the sensor unit 9.

(2) Operation According to the above configuration, when the drive unit 2 AC drives the signal lines Q1 to Q4 with the sensor unit 9 arranged at any of the detection positions of the signal lines Q1 to Q4, The signal lines Q1 to Q4 at the electromagnetic coupling position and the detection coils C1 and C2 of the sensor unit 9 are electromagnetically coupled, and an alternating current is induced in the detection coils C1 and C2. This alternating current flows through the signal carrier coil CT and generates a detection signal on the detection line S1. The detection signal is detected by the detection unit 10, but the waveform corresponds to the combination of the signal lines Q1 to Q4 arranged at the electromagnetic coupling position at the detection position. It can be seen at which detection position of the lines Q1 to Q4.

  The operation of the above-described first example position detection apparatus 1 will be described in more detail with reference to FIG. As shown in the enlarged view in FIG. 4, an AC signal of several kHz to several hundred kHz is applied as an intermittent signal from the drive circuit 8 of the drive unit 2 to the signal lines Q1 to Q4. Here, the state in which alternating current is output is referred to as ON. The signals given to the signal lines Q1 to Q4 are partially overlapped and output for adjacent signal lines.

The outline of the signal induced in the position of the sensor unit 9 and the detection line S1 will be described below with reference to FIGS.
As shown in FIG. 3, at the position A, a signal on the signal line Q1 is induced in the detection coil C1, and a signal on the signal line Q2 is induced in the detection coil C2. Since the winding directions of the detection coil C1 and the detection coil C2 are opposite to each other, when both signals are ON, a signal having a reverse phase is applied to the signal carrier coil CT. As shown in FIG. 4, the signal line Q1 and the opposite phase signal of the signal line Q2 are induced in the detection line S1, and the overlapping portion of the signal line Q1 and the signal line Q2 is induced by turning off the overlapping portion.

  As shown in FIG. 3, at the position B, the signal of the signal line Q2 is induced in the detection coil C1, and there is no signal in the detection coil C2, so that the detection line S1 has the signal line Q2 as shown in FIG. Only the signal is induced.

  As shown in FIG. 3, at the position C, the signal of the signal line Q2 is induced in the detection coil C1, the signal of the signal line Q3 is induced in the detection coil C2, and the signal of the signal line Q2 and the signal line Q3 are induced in the detection line S1. Since the reverse phase signal is induced, as shown in FIG. 4, the signals of the signal line Q2 and the signal line Q3 are induced with the overlapping portion turned OFF.

  As shown in FIG. 3, at the position D, there is no signal in the detection coil C1, and a signal on the signal line Q3 is induced in the detection coil C2, so that the signal line Q3 is reverse to the detection line S1 as shown in FIG. Only the phase signal is induced.

  As shown in FIG. 3, at the position E, the signal of the signal line Q3 is induced in the detection coil C1, the signal of the signal line Q4 is induced in the detection coil C2, and the signal is sent to the detection line S1 as shown in FIG. Since the signal on the line Q3 and the reverse phase signal on the signal line Q4 are induced, the signals on the signal line Q3 and the signal line Q4 are induced with the overlapping portion turned off.

  As shown in FIG. 3, at the position F, there is no signal in the detection coil C1, and signals in the signal line Q3 and the signal line Q4 are induced in the detection coil C2, so that a signal is sent to the detection line S1 as shown in FIG. Only the antiphase signals on lines Q3 and Q4 are induced.

  As shown in FIG. 3, at the position G, the signal of the signal line Q2 is induced in the detection coil C1, and the signals of the signal lines Q3 and Q4 are induced in the detection coil C2. Therefore, as shown in FIG. In S1, a signal on the signal line Q2 and a reverse phase signal on the signal lines Q3 and Q4 are induced, and an overlapping portion of the signal on the signal line Q2 and the signal on the signal line Q3 is induced in an OFF state.

  As described above, the detection unit 10 compares the ON time of the signal induced in the detection line S1 corresponding to the detection position of the sensor unit 9 with the ON time of each drive signal, thereby detecting the detection position of the sensor unit 9. Can know.

(3) Modifications and application examples In the first example, there were four signal lines, two detection coils of the sensor unit 9, and one signal carrying coil. However, by increasing these numbers, It is also possible to increase the detection position.

According to the first example, since the sensor unit is composed of only three coils having a magnetic material, the sensor unit can be reduced in size and weight, and is suitable for a device that reduces the movable part as in liquid level detection.
FIG. 5 shows an outline of a structural example when the position detection device 1 of the first example is applied to a liquid level gauge. A float 21 floats on the liquid surface along a support column 20 erected in the liquid in the storage tank. Can be moved up and down as indicated by the arrows in the figure. The signal lines Q1 to Q4 and the detection line S1 are arranged on the surface of the support column 20 so that the vertical direction in which the liquid level moves is the second direction. Detection coils C1 and C2 and a signal carrying coil CT corresponding to the sensor unit 9 are provided on the inner peripheral surface side of the float 21, and the coils C1, C2 and CT are located at positions corresponding to the signal lines Q1 to Q4. In order to prevent this position from shifting, the float 21 is provided with a rotation stopper (not shown).

  When the liquid level moves up and down and the float 21 moves and the detection positions of the signal lines Q1 to Q4 facing the detection coils C1 and C2 provided in the float 21 change, the detection unit 10 flows through the detection position to the detection line S1. Since it can be detected from the waveform pattern of the AC signal as described above, the position of the liquid level can be known.

  6 and 7 show a more specific structure example when the position detection device 1 of the first example is applied to a liquid level gauge. FIG. 6 floats on the water surface as a float 22 and moves up and down together with the water surface. FIG. 7 is a front view of the column 23 to which the sensor unit 9 is attached. Note that the circuit configuration and operation of the position detection device as the liquid level gauge are substantially the same as those in the first example described with reference to FIGS. 1, 3, and 4.

  The sensor unit 9 shown in FIG. 6 is a part in which various coils described above are embedded in a waterproof structure in a mold resin 24 having a rectangular parallelepiped shape, and a column 23 including a drive unit 2 and a detection unit 10 described later. Is mechanically separate and electrically unconnected and is an independent part. A circular guide hole 24a penetrating vertically is provided in the center of the mold resin 24. Further, a guide recess 24b having a rectangular cross section is opened through the inner peripheral surface of the guide hole 24a in the vertical direction. ing. In the mold resin 24, two detection coils C1, wound around the magnetic body 25 at a predetermined interval in the circumferential direction of the inner peripheral surface at a position close to the inner peripheral surface of the guide hole 24a. C2 and one signal carrier coil CT are provided, and are configured to be electromagnetically coupled to a signal line or the like, which will be described later, disposed along the inner peripheral surface of the guide hole 24a.

  The support | pillar 23 shown in FIG. 7 is a rod-shaped member arrange | positioned with the vertically long attitude | position in the liquid which is going to detect the level of a liquid level. The column 23 is a cylindrical body having an outer diameter slightly smaller than the guide hole 24a of the sensor unit 9, and an anti-rotation rib 23b having a smaller cross-sectional shape than the guide recess 24b of the sensor unit 9 is provided in the vertical direction on the outer peripheral surface thereof. It is formed continuously. Accordingly, when the support 23 is inserted into the guide hole 24 a of the sensor unit 9 and the rotation prevention rib 23 b of the support 23 is inserted into the guide recess 24 b of the sensor unit 9, the sensor unit 9 can move up and down along the support 23. The guide recess 24b and the rotation prevention rib 23b cannot be rotated due to the engagement.

  As shown in FIG. 6, the sheet 3 in which the signal lines Q1 to Q4 and the detection line S1 are sandwiched by an insulating sheet material with a waterproof structure is attached to the outer peripheral surface of the column 23, and the signal lines Q1 to Q1 are attached. The arrangement of Q4 and the detection line S1 is configured such that the vertical direction (the direction of the axis) of the support column on which the liquid level moves is the second direction.

  As shown in FIG. 7, a main body 26 is provided at the upper end of the column 23 where the liquid level does not reach. The main body 26 incorporates the drive unit 2 and the detection unit 10 shown in FIG. 1 in a waterproof or drip-proof structure, and the drive unit 2 is connected to the signal lines Q1 to Q4 of the sheet so that the drive signal is transmitted. The detection unit 10 is connected to the detection line S1, and the position of the sensor unit 9 can be detected by detecting a signal guided to the detection line S1.

  In the above configuration, the support column 23 is arranged in a vertically long posture in the liquid whose level is to be detected, and the sensor unit 9 is inserted into the support column 23 to float on the liquid surface. For example, in the case of detecting the amount of liquid in a liquid storage tank, a support column 23 in which the sensor unit 9 is set is provided in the storage tank, and in the case of measuring the water level of a river or sea for monitoring, the river or sea The device is installed at a predetermined monitoring position.

  The sensor unit 9 that floats on the liquid level is placed at a detection position of any of the signal lines Q1 to Q4 on the column 23 side according to the position of the liquid level. When the drive unit 2 of the main body 26 drives the signal lines Q1 to Q4 with alternating current, the signal lines Q1 to Q4 at the electromagnetic coupling position at the detection position and the detection coils C1 and C2 of the sensor unit 9 are electromagnetically coupled. An alternating current is induced in C1 and C2. This alternating current flows through the signal carrier coil CT and generates a detection signal on the detection line S1. The detection signal is detected by the detection unit 10 of the main body 26. The waveform corresponds to the pattern combination of the signal lines Q1 to Q4 arranged at the electromagnetic coupling position at the detection position. Thus, it can be seen at which detection position of the signal line Q1 to Q4 the sensor unit 9 is arranged. That is, the position of the sensor unit 9 in the longitudinal direction of the column 23 can be determined, and therefore the position of the water surface on which the sensor unit 9 is floating is determined.

2. Second Embodiment (Second Example, FIGS. 8 to 11)
FIG. 8 is a block diagram showing a configuration of the position detection device 30 of the second example, FIG. 9 is a cross-sectional view of the electromagnetic coupling portion in the second example, and FIG. 10 shows signal lines in the sheet of the second example. FIG. 11 is a wiring diagram showing a wiring pattern in relation to an electromagnetic coupling portion, and FIG. 11 is a waveform diagram showing a drive waveform and a detection waveform in the second example.

(1) Configuration The position detection device 30 using electromagnetic induction according to the second example can be used for measuring length or distance with ease of use such as a tape measure.

  As shown in FIG. 8, the main body 31 that is a drive unit of the position detection device 30 includes a power source 4 that converts power supplied from the commercial power source 4 or the battery into a constant voltage, and a signal that serves as a reference for controlling the circuit. An oscillation circuit 5 that generates a signal, a frequency dividing circuit 6 that converts and divides the signal of the oscillation circuit 5 into a required signal, a control circuit 7 that generates a control signal that controls the operation of the signal line, and a control circuit 7 The drive circuit 8 supplies the current from the power source 4 to the electromagnetic coupling unit by the signal from the signal and the electromagnetic coupling unit 32 driven by the drive circuit 8.

  As shown in FIG. 9, the electromagnetic coupling unit 32 includes three drive coils C <b> 4 to C <b> 4 including a magnetic body 15 for generating a magnetic circuit based on an output from the drive circuit 8 and windings wound around the magnetic body 15. C6, and is configured to induce an AC signal on a signal line of a sheet 33 to be described later by the principle of electromagnetic induction.

  As shown in FIG. 8, in the main body 31, a sheet 33 provided with signal lines Q1 to Q3 is wound and housed around a drum body, and the sheet 33 can be fed or wound as required. A take-off mechanism 34 is provided. As shown in FIG. 10, the sheet 33 is a long belt-like member, and three independent signal lines Q1 to Q3 configured in the same pattern as the signal lines of the first example are arranged in the second direction. It is configured to be looped by being routed between the proximal end portion and the distal end portion so as to coincide with the longitudinal direction of the long band shape. As shown in FIG. 9, the signal lines Q1 to Q3 are provided between two upper and lower insulating sheet members, and have a sufficient moisture-proof and waterproof structure.

  As shown in FIGS. 8 and 10, a power source circuit 35 that converts an alternating current signal flowing in the signal lines Q <b> 1 to Q <b> 3 on the sheet 33 into a direct current to be a circuit power source 4 and a signal line The waveform shaping circuit 36 that amplifies and stabilizes the alternating current signals of Q1 to Q3, the arithmetic circuit 12 that calculates the distance from which the sheet 33 is drawn by determining the signals of the signal lines Q1 to Q3, and the calculated data are displayed. A detection unit 10 is provided in which the display 13 is housed in a housing 37.

  As shown in FIGS. 8 and 9, the sheet 33 is led out of the main body 31 through three drive coils C <b> 4 to C <b> 6 provided in the electromagnetic coupling portion 32 of the main body 31. Since the signal lines Q1 to Q3 of the sheet 33 pass through the magnetic circuits of the drive coils C4 to C6 that are AC driven by the drive circuit 8, the signal lines Q1 to Q3 provided on the sheet 33 are used. The AC signal is induced by electromagnetic induction according to the wiring pattern of the signal lines Q1 to Q3 at the portion facing each of the drive coils C4 to C6, and the AC signal is detected by the detection unit 10.

  In other words, the currents induced by the drive coils C4 to C6 flow through the signal lines Q1 to Q3 of the sheet 33 passing through the electromagnetic coupling unit 32, but the sheet 33 is fed from the main body 31 to each of the signal lines Q1 to Q3. Since whether or not an induced electromotive force is generated at each detection position when being pulled out is set by a wiring pattern, the detection position of the sheet 33 corresponding to the pull-out length (facing the drive coils C4 to C6) Can be determined from the waveform of the AC signal generated on the signal lines Q1 to Q3.

(2) Operation According to the above configuration, if the electromagnetic coupling unit 32 is AC driven by the drive circuit 8 with the sheet 33 pulled out from the winding mechanism 34 by an arbitrary length, the signal lines Q1 to Q3 have An AC signal is induced by electromagnetic induction, and this AC signal is detected by the detection unit 10 provided at the leading end of the drawn sheet 33. Here, the AC signal detected by the detection unit 10 has a waveform corresponding to the wiring pattern of the signal lines Q1 to Q3 of the sheet 33 that the drive coils C4 to C6 of the electromagnetic coupling unit 32 face each other. It can be determined from the waveform which of the plurality of detection positions set on the signal lines Q1 to Q3 and the electromagnetic coupling portion 32 face each other, and how long the sheet 33 is pulled out from the winding mechanism 34. Can be judged.

  Accordingly, if the main body 31 is installed at the measurement starting point and the sheet 33 is pulled out in the measurement direction, the sheet 33 is pulled out while passing through the electromagnetic coupling portion 32, and the detection positions A to O of the sheet 33 are electromagnetically coupled. The current passes through the drive coils C1 to C3 through the signal lines Q1 to Q3, and sequentially passes and moves through the section 32. Therefore, by looking at the display on the display unit 13 and stopping the drawing of the sheet 33 when an appropriate detection position is detected, the length from the measurement starting point to the leading end of the sheet 33 can be measured.

  The effect | action in the position detection apparatus 30 of the 2nd example mentioned above is demonstrated still in detail with reference to FIG. As shown in the enlarged view in FIG. 11, an AC signal of several kHz to several hundred kHz is applied as an intermittent signal from the drive circuit 8 of the main body 31 to the drive coils C4 to C6. Here, the state in which alternating current is output is referred to as ON. Each type of signal induced in the signal lines Q1 to Q3 is determined by the time difference from the signal serving as the base point. Therefore, the drive signal given to the drive coils C4 to C6 is given by the time difference after a long ON signal. The continuous waveform is ON for a predetermined time.

Hereinafter, the outline of the detection position of the sheet 33 facing the electromagnetic coupling unit 32 and the signal waveforms induced in the signal lines Q1 to Q3 at that time will be described with reference to FIGS.
As shown in FIG. 10, at the position A, there is only the signal line Q1 corresponding to the drive coil C4 of the electromagnetic coupling section 32. Therefore, as shown in FIG. 11, the signal of the drive coil C4 is induced on the signal line Q1. No signal is induced in the other signal lines Q2 and Q3.

  As shown in FIG. 10, at the position C, the signal line Q1 corresponds to the drive coil C4 of the electromagnetic coupling unit 32, the signal line Q2 corresponds to the drive coil C5, and the signal line Q3 corresponds to the drive coil C6. As shown in FIG. 11, the signal of the drive coil C4 is induced in the signal line Q1, the signal of the drive coil C5 is induced in the signal line Q2, and the signal of the drive coil C6 is induced in the signal line Q3. Is induced.

  As shown in FIG. 10, at the position D, the signal line Q1, the signal line Q2, and the signal line Q3 corresponding to the drive coil C6 respectively exist corresponding to the drive coil C4 of the electromagnetic coupling unit 32. As shown in FIG. 2, the signal of the drive coil C1 is induced on the signal lines Q1 and Q2, and the signal of the drive coil C6 is induced on the signal line Q3.

  As shown in FIG. 10, at the position H, the signal line Q1 passes through the drive coils C4 and C5. Therefore, as shown in FIG. 11, the signal line Q1 includes the signal of the drive coil C4 and the drive coil. A signal combined with the C5 signal is induced. Since the signal line Q2 and the signal line Q3 do not pass through any of the drive coils, no signal is induced.

  As shown in FIG. 10, at the position K, the signal line Q1 and the signal line Q2 pass through the drive coil C5. Therefore, as shown in FIG. 11, the signal line Q1 and the signal line Q2 include the drive coil C5. Signal is induced. The signal line signal line Q3 does not pass any drive coil, so no signal is induced.

  As shown in FIG. 10, at the position M, the signal line Q1 passes through the drive coil C5 and the signal line Q2 passes through the drive coil C6. Therefore, as shown in FIG. A signal is induced, and a signal of the drive coil C6 is induced on the signal line Q2. Since the signal line Q3 does not pass through any of the drive coils, no signal is induced.

  As shown in FIG. 10, at the position O, the signal line Q2 exists corresponding to the drive coil C5 and the signal line Q3 exists corresponding to the drive coil C6. Therefore, as shown in FIG. A signal of the drive coil C5 is induced in Q2, and a signal of the drive coil C6 is induced in the signal line Q3. Since the signal line Q1 does not pass through any of the drive coils, no signal is induced.

(3) Modifications / applications, etc. In the second example, there are three signal lines and three drive coils for the electromagnetic coupling unit 32. By increasing these numbers, the detection position can be increased. Is also possible.

  According to the second example, since the length of the sheet 33 pulled out from the main body 31 can be displayed on the display unit 13 provided at the tip of the sheet 33, the sheet 33 pulled out from the starting point where the main body 31 is provided. It can be used like a tape measure as a measuring instrument that measures the distance to the measurement point reached by the tip.

3. 3rd Embodiment (3rd example, FIGS. 12-15)
FIG. 12 is a block diagram showing the configuration of the position detection device 40 of the third example, FIG. 13 is a cross-sectional view of the electromagnetic coupling part in the third example, and FIG. 14 shows signal lines in the sheet of the third example. FIG. 15 is a wiring diagram showing a wiring pattern in relation to an electromagnetic coupling portion, and FIG. 15 is a waveform diagram showing a drive waveform and a detection waveform in the third example.

(1) Configuration As shown in FIG. 12, the position detection device 40 using electromagnetic induction in the third example includes a plurality of electrically independent (three in this example) signal lines Q1 to Q3. Have. These signal lines Q1 to Q3 are arranged in a direction (first direction) orthogonal to the lines, are extended in the longitudinal direction (second direction), and are configured in a closed loop as a whole. Is formed as a special coding area.

  As shown in FIG. 12, the drive unit 2 ′ of the position detection device 40 generates a power source 4 that converts the power supplied from the commercial power source 4 or the battery into a constant voltage, and a signal that serves as a reference for controlling the circuit. An oscillation circuit 5 to be generated, a frequency dividing circuit 6 that converts and divides the signal of the oscillation circuit 5 into a required signal, a control circuit 7 that generates a control signal for controlling an operation to the signal line, It has a drive circuit 8 for supplying a current from the power source 4 as a reference signal to the drive coils C4 to C6 of the electromagnetic coupling unit 41 installed at a position other than the coded region of the signal line by a control signal.

  As shown in FIG. 12, the detection unit 10 ′ of the position detection device 40 is an amplifier that amplifies signals from the detection coils C1 to C3 of the electromagnetic coupling unit 42 arranged in the coding regions of the signal lines Q1 to Q3. 11 and the drive signal applied to the drive coils C4 to C6 as a reference signal and the signals from the detection coils C1 to C3 amplified by the amplifier 11 are installed in the coding region of the signal lines Q1 to Q3. It has the arithmetic circuit 12 which calculates the position of the part 42, and the indicator 13 which displays the result. In addition, it can also be set as the structure which provides the external device controlled with the signal which shows the position of the electromagnetic coupling part 42 which the arithmetic circuit 12 calculated instead of the indicator 13 or with the indicator 13. FIG.

  The two electromagnetic coupling portions 41 and 42 on the drive side and the detection side described above have the same configuration, and as shown in FIG. 13, the configuration is substantially the same as the electromagnetic coupling portion 32 of the second example (FIG. 9) (FIG. 13 illustrates the drive side). That is, the drive coils C4 to C6 have a magnetic body 15 for generating a magnetic circuit by an output from the drive circuit 8 and a winding wound around the magnetic body, and the signal lines Q1 to Q3 are in the magnetic circuit. By passing, electric power is induced in the signal line by electromagnetic induction. The detection coils C <b> 1 to C <b> 3 detect a current flowing through the signal line as a signal by a winding wound around the magnetic body 15 by magnetic coupling. In the third example, the drive unit 2 ′ having the drive-side electromagnetic coupling unit 41 and the detection unit 10 ′ having the detection-side electromagnetic coupling unit 42 are configured separately from the signal lines Q1 to Q3. The sensor unit 45 is configured integrally as a part.

  In the position detection device 40 using electromagnetic induction of the third example, the signal lines Q1 to Q3 are sandwiched between two sheets of insulating upper and lower sheets as shown in FIG. It is configured as a sheet 43, which is a flaky independent component part. The sheet 43 has a long strip shape as shown in FIG. The signal lines Q <b> 1 to Q <b> 3 have the same pattern as the signal lines of the first example, and the base end portion and the tip end portion of the sheet 43 so that the second direction coincides with the longitudinal direction of the long strip shape of the sheet 43. It is routed between and is configured in a loop.

  As shown in FIG. 14, the signal lines Q1 to Q3 provided in the sheet 43 have a drive coil of the electromagnetic coupling unit 41 on the drive unit 2 ′ side on one side (lower side in FIG. 14) along the longitudinal direction. A straight line portion to which a drive signal which is a reference signal is given by C4 to C6, and the other side along the longitudinal direction (upper side in FIG. 14) is a signal line Q1 to Q3 for each detection position A to O. Are coded regions formed by wiring patterns having different combinations of whether or not each is at an electromagnetic coupling position. If the detection coils C1 to C3 of the electromagnetic coupling unit 42 on the detection unit 10 'side are arranged in the coded region, a detection signal that is a combination of drive signals corresponding to the arranged detection positions A to O can be obtained. As described above, the signal lines Q1 to Q3 in the third example have the drive signal and the coding region where the signal is extracted adjacent to each other in the same direction. Drive and detection can be performed by moving the electromagnetic coupling portions 41 and 42 of the integrated sensor unit 45 along the wiring.

(2) Operation In the above configuration, the electromagnetic coupling portions 41 and 42 of the sensor unit 45 are placed at predetermined positions on the sheet 43 such that the sheet 43 is laid on the measurement target and normally faces the signal lines Q1 to Q3. The electromagnetic coupling portions 41 and 42 of the sensor unit 45 are moved along the longitudinal direction while the drive coils 8 are AC driven by the drive circuit 8. An AC signal is induced on the signal lines Q1 to Q3 by electromagnetic induction. This AC signal induces an AC signal in the detection coils C1 to C3, and this AC signal is detected by the detection unit 10 ′. Here, the AC signal detected by the detection unit 10 ′ is set to be different for each detection position A to O of the signal lines Q1 to Q3 of the sheet 43 facing the drive coils C4 to C6. Therefore, it is possible to determine from the waveform which one of the plurality of detection positions A to O set in the signal lines Q1 to Q3 and the electromagnetic coupling portion 42 face each other, and the length of the sheet 43 It can be determined at which position in the direction the electromagnetic coupling part 42 of the sensor unit 45 is present.

  The effect | action in the position detection apparatus 40 of the 3rd example mentioned above is demonstrated still in detail with reference to FIG. An AC signal of several kHz to several hundred kHz is applied as an intermittent signal from the drive circuit 8 to the drive coils C4 to C6 of the electromagnetic coupling unit 41. Here, the state in which alternating current is output is referred to as ON.

  The detection coils C4 to C6 of the electromagnetic coupling unit 32 of the detection unit 10 ′ move the signal line by the drive coils C4 to C6 by moving the coding region of the signal line that is patterned so that the position information data is obtained. The combination signal can be detected as a position detection signal by combining the ON times of the AC signals induced in Q1 to Q3.

The outline of each detection position of the sheet 43 facing the detection coil of the electromagnetic coupling unit 32 on the driving side and the signal waveform induced in the detection coil of the electromagnetic coupling unit 32 at that time will be described with reference to FIGS. I will explain.
As shown in FIG. 14, at the position A, since there is only the signal line Q1 corresponding to the detection coil C1, as shown in FIG. 15, the signal of the drive coil C4 is induced in the detection coil C1, and the other Since there is no corresponding signal line in the detection coils C2 and C3, no signal is induced.

  As shown in FIG. 14, at the position B, since the signal line Q1 and the detection coil C2 have a signal line Q2 corresponding to the detection coil C1, as shown in FIG. 15, the detection coil C1 has a drive coil C4, A signal from the drive coil C5 is induced in the detection coil C2, and no signal is induced because there is no corresponding wiring in the detection coil C3.

  As shown in FIG. 14, at the position C, there is a signal line Q1 corresponding to the detection coil C1, a signal line Q2 corresponding to the detection coil C2, and a signal line Q3 corresponding to the detection coil C3. As shown in FIG. 15, the drive coil C4 is induced in the detection coil C1, the drive coil C5 is induced in the detection coil C2, and the drive coil C6 is induced in the detection coil C3.

  As shown in FIG. 14, at the position E, the signal lines Q1 and Q2 correspond to the detection coil C1, and the signal line Q3 corresponds to the detection coil C2. Therefore, as shown in FIG. The signals of the drive coils C4 and C5 are induced in the coil C1, the signal of the drive coil C6 is induced in the detection coil C2, and no signal is induced because there is no corresponding signal line in the detection coil C3.

  As shown in FIG. 14, at the position G, there is a signal line Q1 corresponding to the detection coil C1, and a signal line Q2 corresponding to the detection coil C3, so that the detection coil C1 is driven as shown in FIG. The signal of the coil C1 is induced, the signal of the drive coil C2 is induced in the detection coil C3, and no signal is induced because there is no corresponding signal line in the detection coil C2.

  As shown in FIG. 14, at the position of H, since there is a signal line Q1 corresponding to the detection coils C1 and C2, as shown in FIG. 15, the signal of the drive coil C4 is induced in the detection coils C1 and C2, Since there is no corresponding signal line in the detection coil C3, no signal is induced.

  As shown in FIG. 14, at the position J, there is a signal line Q1 corresponding to the detection coil C1, there are signal lines Q1 and Q2 corresponding to the detection coil C2, and signal line Q3 corresponding to the detection coil C3. Therefore, as shown in FIG. 15, the signal of the drive coil C4 is induced in the detection coil C1, the signals of the drive coils C4 and C5 are induced in the detection coil C2, and the signal of the drive coil C6 is induced in the detection coil C3. A signal is induced.

  As shown in FIG. 14, since there are signal lines Q1 and Q2 corresponding to the detection coil C2 at the position L, the signals of the drive coils C4 and C5 are induced in the detection coil C2, as shown in FIG. The Since there is no corresponding signal line in the detection coils C1 and C3, no signal is induced.

  As shown in FIG. 14, at the position M, there is a signal line Q1 corresponding to the detection coil C2, and there is a signal line Q2 corresponding to the detection coil C3. Therefore, as shown in FIG. The signal of the drive coil C4 is induced, and the signal of the drive coil C5 is induced in the detection coil C3. Since there is no corresponding signal line in the detection coil C1, no signal is induced.

  As shown in FIG. 14, at the position N, there is a signal line Q2 corresponding to the detection coil C3. Therefore, as shown in FIG. 15, a detection coil in which the signal of the drive coil C5 is induced in the detection coil C3. Since there is no corresponding signal line in C1 and C2, no signal is induced.

  As shown in FIG. 14, at the position O, since there is a signal line Q2 corresponding to the detection coil C2, as shown in FIG. 15, a detection coil in which the signal of the drive coil C5 is induced in the detection coil C2. Since there is no corresponding signal line in C1 and C3, no signal is induced.

(3) Modifications, application examples, etc. In the third example, there are three signal lines and three drive coils and three detection coils for the sensor unit 45, but the detection position can be increased by increasing these numbers. It is also possible to increase.

  When the position detection device 40 of the third example is applied to the length measurement, the sheet 43 is laid on a measurement target (for example, on the ground such as the ground), and the drive unit 2 ′ and the detection unit 10 ′ are operated. However, the sensor unit 45 having the electromagnetic coupling portions 41 and 42 is moved along the longitudinal direction of the sheet 43 (along the second direction of the signal line), and the detection result of the detection unit 10 ′ is displayed on the display unit 13. If the sensor unit 45 is stopped at a desired position while checking, the desired movement length (reference position) of the sensor unit 45 or the electromagnetic coupling part 42 is determined based on the detection result of the detection unit 10 ′ indicating the movement amount of the electromagnetic coupling part 42. A predetermined distance).

  Further, the position detection device 40 of the third example connects the sheet 43 provided on the measurement target and the sensor unit 45 (electromagnetic coupling portions 41 and 42) that move on the sheet 43 for measurement of the measurement target by wiring. This is not necessary, and the measurement resolution and detection position can be easily dealt with by changing the wiring on the sheet 43 side, which is suitable for detecting the position of the moving body and the position of the rotating body.

  FIG. 16 shows a specific configuration example when the above-described third example is applied to the position detection of a moving object. The sheet 43 is fixed to the upper surface serving as a measurement surface of the moving body 50, and the sensor unit 45 is disposed at a position facing the sheet 43.

  In such an arrangement, it is assumed that the driving unit 2 ′ of the sensor unit 45 applies an AC signal as an intermittent signal to each of the driving coils C4 to C6, and the moving body 50 moves by a certain length along the second direction in this state. . The detection coils C4 to C6 of the sensor unit 45 move relative to the sheet 43 along the coded region of the sheet 43 in which signal lines are patterned so that position information data can be obtained. In accordance with the position of the coding area 45 facing, the combination signal of the ON time of the AC signal induced in the signal lines Q1 to Q3 is detected and output as a position detection signal.

  If the detection result is confirmed on the display unit 13 of the detection unit 10 ′ of the sensor unit 45 when the moving body 50 is moved at a certain distance and stopped at a certain position, each position A to each of the coding regions having different position detection signals is obtained. Since the distance from the reference position (starting point to measurement start position) of O is known, the distance that the moving body has moved from the reference position can be obtained.

  FIG. 17 shows a specific configuration example when the above-described third example is applied to the position detection of the rotating body. The disc-shaped rotator 51 is rotatable about a rotation axis (not shown) at the center of the figure of the disc, and a driving force is applied from a rotator driving unit 52 that rotates in contact with the outer peripheral surface. Rotate. The sheet 43 is fixed to the outer peripheral surface of the rotating body so that the circumferential direction is the second direction, and the sensor unit 45 is disposed at a position facing the sheet 43. In FIG. 17, the sensor unit 45 includes electromagnetic coupling portions 41 and 42 disposed facing the sheet 43 of the rotating body 51, and a drive unit 2 ′ and a detection unit 10 ′ as a control unit main body that controls the electromagnetic coupling units 41 and 42. They are shown separately.

  In such an arrangement, it is assumed that the drive unit 2 ′ of the control unit main body of the sensor unit 45 applies an AC signal as an intermittent signal to each of the drive coils C <b> 4 to C <b> 6 and rotates the rotating body 51 by a certain length in this state. The detection coils C4 to C6 of the sensor unit 45 move relative to the sheet 43 along the coded region of the sheet 43 in which signal lines are patterned so that position information data can be obtained. In accordance with the position of the coding area 45 facing, the combination signal of the ON time of the AC signal induced in the signal lines Q1 to Q3 is detected and output as a position detection signal.

  If the detection result is confirmed on the display unit 13 in the detection unit 10 ′ of the control unit main body of the sensor unit 45 when the rotating body 51 stops at a certain position, each position A of the coding area where the position detection signal is different. Since the rotation angle from the reference position (starting point or measurement start position) of ~ O is known, the rotation position of the rotating body 51 (the amount rotated from the reference position (rotation angle)) can be obtained.

  Moreover, if the detection part 10 'of the control part main body outputs the data of the rotational position of the rotary body 51 obtained from the detection coils C1 to C3 to the rotary body drive part 52 and uses it for the drive control, Stop and speed control are possible.

FIG. 1 is a block diagram illustrating a configuration of the position detection device of the first example. FIG. 2 is a cross-sectional view of a sensor unit as an electromagnetic coupling portion in the first example. FIG. 3 is a wiring diagram showing the wiring pattern of the signal lines in the first example in relation to the sensor unit. FIG. 4 is a waveform diagram showing a drive waveform and a detection waveform in the first example. FIG. 5 is a perspective view schematically showing a structural example of a specific application example of the first example. FIG. 6 is a cross-sectional view showing a more specific application example of the first example. FIG. 7 is a front view showing a more specific application example of the first example. FIG. 8 is a block diagram illustrating a configuration of the position detection device of the second example. FIG. 9 is a cross-sectional view of the electromagnetic coupling portion in the second example. FIG. 10 is a wiring diagram showing the wiring pattern of the signal lines in the sheet of the second example in relation to the electromagnetic coupling portion. FIG. 11 is a waveform diagram showing a drive waveform and a detection waveform in the second example. FIG. 12 is a block diagram illustrating a configuration of the position detection device of the third example. FIG. 13 is a cross-sectional view of the electromagnetic coupling portion in the third example. FIG. 14 is a wiring diagram showing a wiring pattern of signal lines in the sheet of the third example in relation to the electromagnetic coupling portion. FIG. 15 is a waveform diagram showing a drive waveform and a detection waveform in the third example. FIG. 16 is a cross-sectional view showing a case where the position detection device of the third example is used for position detection of a moving body. FIG. 17 is a schematic plan view showing a case where the position detection device of the third example is used for position detection of a rotating body.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,30,40 ... Position detection apparatus 2,2 '... Drive part 3,33,43 ... Sheet (flexible pattern board | substrate)
DESCRIPTION OF SYMBOLS 9 ... Sensor unit as an electromagnetic coupling part 10, 10 '... Detection part 31 ... Main body as a drive part 32, 41, 42 ... Electromagnetic coupling part 34 ... Winding mechanism 45 ... Sensor unit as an electromagnetic coupling part 50 ... Moving body 51 ... Rotating body C1-C3 ... Detection coil C4-C6 ... Drive coil CT ... Signal transfer coil Q1-Q4 ... Signal line S1 ... Detection line

Claims (5)

A plurality of electrically independent wirings arranged in the first direction and extending in the second direction, wherein the electromagnetic coupling position of each wiring is determined in the first direction, and a plurality of wirings are arranged along the second direction. A plurality of signal lines formed in a wiring pattern such that a combination of whether or not each wiring is in the respective electromagnetic coupling position is different for each detection position;
An electromagnetic having a plurality of coils which are provided so as to be relatively movable along the second direction of the signal line and are set at the electromagnetic coupling positions of the signal lines when arranged at the detection positions. A coupling part;
A drive unit that AC drives each of the plurality of signal lines or the coils of the electromagnetic coupling unit;
When the plurality of signal lines or the coils of the electromagnetic coupling unit are AC driven by the driving means, induction is performed on the coils of the electromagnetic coupling unit or the signal lines by electromagnetic induction at the electromagnetic coupling positions. A detection unit that detects an AC signal to be detected and detects a position of the electromagnetic coupling unit in the second direction of the signal line;
A position detection device characterized by comprising: The signal lines are electrically independent from each other, arranged in the first direction so as to be adjacent to the signal lines, extend in the second direction, and are defined in the first direction at the plurality of detection positions. Formed with a wiring pattern to be arranged at the electromagnetic coupling position, further comprising a detection line connected to the detection unit,
The plurality of coils of the electromagnetic coupling unit are detection coils in which alternating current is induced by alternating current flowing through the signal lines at the electromagnetic coupling positions when the coils are arranged at the detection positions of the signal lines.
The electromagnetic coupling unit further includes a signal carrying coil set to the detection line when arranged at each detection position, and the detection coil is connected in series to the signal carrying coil,
When the driving means drives the signal line with alternating current, an alternating current is induced in the detection coil in the electromagnetic coupling portion arranged at any of the detection positions of the signal line, and this alternating current flows to the signal carrier coil. A detection signal is generated on the detection line, and the detection unit detects the detection signal to detect which detection position of the signal line the electromagnetic coupling unit is disposed. The position detection device according to claim 1. The drive unit, the electromagnetic coupling unit that is AC-driven by the drive unit, and a winding mechanism that is provided with the signal line and that allows a sheet having the second direction as a longitudinal direction to be taken in and out through the electromagnetic coupling unit. Has a body provided with
The detection unit for detecting the feeding length of the sheet from the waveform of alternating current generated in the signal line is provided at the tip of the sheet,
The detection means detects the alternating current induced in the signal line of the sheet by the drive means AC driving the coil of the electromagnetic coupling unit, so that any detection position of the signal line of the sheet is the The position detection device according to claim 1, wherein the position detection device detects whether the sheet is located at an electromagnetic coupling portion and detects a length of the sheet pulled out from the main body. The plurality of signal lines are each formed in a closed loop shape on a sheet having the second direction as a longitudinal direction, and one side thereof along the second direction is formed by the wiring pattern and along the second direction. The other side is formed so as to be parallel to the second direction at a certain interval at the detection position on the one side,
The plurality of coils of the electromagnetic coupling unit are connected to the detection unit, and when arranged at the respective detection positions of the signal line, alternating current flows through the respective signal lines at the respective electromagnetic coupling positions. Is a detection coil that is induced,
The electromagnetic coupling unit is connected to the driving unit, and drives the signal line with an alternating current by an alternating current provided from the driving unit when the electromagnetic coupling unit is disposed at each of the detection positions on the other side of the signal line. A coil is further provided,
When the drive means AC drives the drive coil of the electromagnetic coupling unit, an alternating current is induced in the signal line of the sheet, and this alternating current induces an alternating current in the detection coil of the electromagnetic coupling unit. The position detection device according to claim 1, wherein the position detection device detects at which detection position of the signal line of the sheet the electromagnetic coupling unit is set by being detected by the detection unit. The alternating current given to the signal line or the coil by the drive unit is an intermittent signal, and the detection unit detects a relative position of the signal line and the electromagnetic coupling unit in the second direction by a combination of the intermittent signals. The position detection device according to claim 1.

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