JP4718881B2 - Position detection device - Google Patents

Description

  The present invention relates to a position detection device.

There is a printer that performs printing on a recording medium (paper) by a print head while reciprocating a head carriage on which the print head is mounted.
As such a printer, a printer having a position detection device for detecting the position of the head carriage in order to control the movement of the head carriage has been proposed (see Patent Document 1).
In other words, this position detection device includes a magnetic scale provided with a magnetic scale provided along the longitudinal direction of the guide shaft on the outer peripheral surface of an axial guide shaft for guiding the print head, and a magnetic scale provided integrally with the print head. And a magnetic sensor that outputs a detection signal by detecting a change in the magnetic field of the scale.
In this position detection device, the position of the head carriage in the longitudinal direction of the guide shaft is obtained based on the detection signal.
Such a position detection device using a magnetic scale is widely applied to various machine tools and automatic machines that require position detection.
JP 62-226007 A

By the way, in order to improve durability, the present applicant provides a magnetic scale provided with a magnetic scale extending linearly along the longitudinal direction of the pipe material in a part of the inner surface of the pipe material in the circumferential direction.
In such a magnetic scale, the detection signal detected by the magnetic sensor has an optimum magnitude, that is, the magnetic sensor faces the outer surface portion of the pipe material provided with the magnetic scale. Therefore, it is necessary to adjust the position of the pipe material in the circumferential direction.
However, if such adjustment work is adjusted by measuring the position of the magnetic sensor and the position of the magnetic scale, the work becomes complicated and the efficiency of the adjustment work cannot be increased.
This invention is made | formed in view of such a situation, The objective is to provide the position detection apparatus which can perform the position adjustment in the circumferential direction of the pipe material with respect to a magnetic sensor easily.

In order to achieve the above object, the present invention is a tubular pipe material and is attached to a part of the inner surface of the pipe material in the circumferential direction and extends linearly along the longitudinal direction of the pipe material. A magnetic scale having a magnetic member formed with a magnetic scale along the direction of movement, and a head holder that is slidably connected to the magnetic scale and is disposed so as to be reciprocally linearly movable in the extending direction of the magnetic scale. Prepare.
In addition, a detection sensor provided integrally with the head holder so as to be movable along the longitudinal direction of the magnetic scale and detecting the magnetic scale and generating a detection signal is selectively selected from two different notification forms. Notification means that can be performed, control means for switching the notification mode of the notification means based on the magnitude of the detection signal output from the detection sensor, and a head carrier that houses this control means and is connected to the head holder .
Further, in the above-mentioned head holder, two flat chips provided on both ends in the longitudinal direction of the magnetic scale and formed with flat surfaces facing the both ends, respectively, project from the side surface of the head carrier, and the flat surfaces of the flat chips are A connecting mechanism that connects the head holder and the head carrier, and includes two pressing pins that contact the tip, and a biasing member that biases at least one of the two pressing pins toward the flat surface of the planar chip. It is provided.

  According to the present invention, it is possible to determine whether or not the magnetic scale is located at a position facing the detection sensor based on the notification of the notification means. This is advantageous in simplifying the operation of adjusting the position of the pipe material in the circumferential direction with respect to the detection sensor.

(First embodiment)
Next, a first embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram illustrating a configuration of a control system of the position detection apparatus according to the first embodiment.
FIGS. 2A and 2B are explanatory views showing the display of the light emitting diodes of the position detection apparatus according to the first embodiment.
FIG. 3 is a configuration diagram of the position detection apparatus according to the first embodiment, and FIG. 4 is a cross-sectional view taken along line AA of FIG.
5 is a front view of the head holder and the head carrier, FIG. 6 is a view as seen from the arrow A in FIG. 5, and FIG. 7 is a view as seen from the arrow B in FIG.
8 is a front view of the head holder and the head carrier, FIG. 9 is a sectional view taken along line BB in FIG. 8, and FIG. 10 is a sectional view taken along line CC in FIG.
FIG. 11A is a plan view of the clamp member, and FIG. 11B is a view taken in the direction of arrow B in FIG.

As shown in FIGS. 3 to 10, the position detection device 100 includes a magnetic scale 10, a head holder 20, a magnetic sensor 30 (corresponding to a detection sensor in claims), and a head carrier 40. .
The position detection device 100 is used for detecting the position of a moving member in various fields, for example, when detecting the position of a table on a bed in a machine tool or when detecting the position of a print head in a printer. The magnetic scale 10 is provided along the moving direction of the moving member, and the head holder 20 is attached to the moving member or formed as a part of the moving member. Both ends thereof are appropriately fixed at positions.
As shown in FIG. 4, the magnetic scale 10 includes a pipe material 12 and a magnetic member 14.
The pipe member 12 is formed in a cylindrical shape in cross section, and is formed of a material that does not magnetically affect the magnetic force of the magnetic member 14.
In the present embodiment, the material of the pipe material 12 is stainless steel SUS304 (JIS), which is a nonmagnetic material. The material of the pipe member 12 may have weak magnetism as long as it does not affect the magnetic force of the magnetic member 14 magnetically.

As shown in FIG. 4, the magnetic member 14 is provided on the inner surface 1202 of the pipe material 12 so as to extend along the longitudinal direction of the pipe material 12 while being in close contact with the inner surface 1202.
The magnetic member 14 is formed in the shape of a circular strip, and the magnetic member 14 has an outer surface 1402 that is in close contact with the inner surface 1202 of the pipe member 12 and an inner surface 1404 that faces the inner space of the pipe member 12.
In the present embodiment, the magnetic member 14 is attached to a part of the inner surface 1202 of the pipe material 12 in the circumferential direction and extends linearly along the longitudinal direction of the pipe material 12.
The magnetic member 14 can be magnetized, and a magnetic scale is formed by alternately magnetizing N poles and S poles at a constant pitch along the extending direction. In other words, the magnetic member 14 is formed with a magnetic scale including a periodic signal in which the N pole and the S pole alternately change along the extending direction. In other words, the magnetic member 14 is recorded with a periodic magnetic pattern in which the N pole and the S pole are alternately changed along the extending direction.
In this embodiment, the magnetic member 14 is formed of a rubber magnet as an elastic material.
The magnetic member 14 is attached to the inner surface 1202 of the pipe material 12 by bonding the inner surface 1202 of the pipe material 12 and the outer surface 1402 of the magnetic member 14 of the magnetic member 14 with a double-sided adhesive tape or an adhesive. The outer surface 1402 of the member 14 is in close contact with the inner surface 1202 of the pipe material 12.

Magnetization of the magnetic member 14, that is, formation of a magnetic scale, is performed using a dedicated magnetizing device.
The magnetizing device includes a magnetic head and a drive circuit that generates a magnetic field from the magnetic head by supplying a drive current to the magnetic head.
The magnetizing device applies a magnetic field from the magnetic head to the magnetic member 14 while relatively moving the magnetic head along the longitudinal direction of the magnetic member 14 with the magnetic head facing the magnetic member 14. Thus, a magnetic scale is formed by magnetizing the N pole and S pole with a constant pitch on the magnetic member 14.
The magnetic scale for the magnetic member 14 is formed by attaching the magnetic member 14 to the inner surface 1202 of the pipe member 12 of the pipe member 12 and then facing the magnetic head to the outer surface of the pipe member 12 of the pipe member 12. 12 may be performed by applying the magnetic field through 12, or before the magnetic member 14 is attached to the pipe member 12, the magnetic head may be directly exposed to the magnetic member 14 alone.
However, when the magnetic graduation is formed after the magnetic member 14 is attached to the inner surface 1202 of the pipe member 12, the mounting error on the inner surface 1202 of the magnetic member 14 or the deformation of the pipe member 12 is caused by the magnetic member. Since the influence on the pitch of the 14 N poles and the S poles can be eliminated, the accuracy of the magnetic scale can be ensured compared with the case where the magnetic scale is formed by magnetizing the magnetic member 14 alone, and the magnetic sensor 30. This is advantageous in detecting the detection signal with high accuracy.

As shown in FIGS. 4 and 10, the head holder 20 includes a holder main body 22 and a connecting portion 23 provided on the holder main body 22 and slidably connected to the magnetic scale 10. The magnetic scale 10 is arranged so as to be capable of reciprocating linear movement in the extending direction.
The connecting portion 23 includes a clamp member 24, an annular member 26, and the like.
As shown in FIGS. 9 and 10, the holder body 22 is provided with a pipe material insertion hole through which the pipe material 12 is inserted in the length direction. The pipe material insertion hole is larger than the pipe material 12. A hole 2202 having an inner diameter of a size and a large-diameter hole 2204 respectively formed at locations near both ends of the hole 2202 in the length direction.
The magnetic sensor 30 is disposed so as to face the hole 2202 at the center in the length direction of the head holder 20, and therefore the magnetic sensor 30 is integrated with the head holder 20 along the longitudinal direction of the magnetic scale 10. It is provided to be movable.
A fitting groove 2206 is formed in the length direction of the holder body 22 so as to communicate with the large diameter hole 2204 at a position of the large diameter hole 2204 having the same phase as the position where the magnetic sensor 30 is located in the circumferential direction of the hole 2202. ing.

Two clamp members 24 are provided, and are respectively disposed on the inner surface of the large-diameter hole 2204.
In the present embodiment, the clamp member 24 is preferably made of a material having elasticity and good slidability (small coefficient of friction) and high wear resistance. For example, a synthetic resin material such as POM or fluorine-based synthetic resin. Is formed by.
As shown in FIGS. 10 and 11, the clamp member 24 includes a base portion 2402 and a pair of arm portions 2404 extending from the base portion 2402 in opposite directions along the circumferential direction of the outer surface of the pipe material 12. .
The base portion 2402 engages with the fitting groove 2206, whereby the clamp member 24 is disposed in the large diameter hole 2204 so as not to rotate.
A reference surface 2406 that can contact the outer surface of the pipe material 12 is formed on the base portion 2404. Since the base portion 2402 engages with the fitting groove 2206, the reference surface 2406 is provided at a location having the same phase as the location where the magnetic sensor 30 is located in the circumferential direction of the hole 2202.
Protrusions 2408 that urge the outer surfaces of the pipe material 12 in a direction to press the outer surface of the pipe material 12 against the reference surface 2402 are provided at the tips of the two arm portions 2404, respectively.

As shown in FIG. 10, the annular member 26 is disposed so as to face the outer end face 2410 of each clamp member 24 positioned opposite to the inner end face where the two clamp members 24 face each other.
The annular member 26 is made of a material having elasticity and is impregnated with lubricating oil. As such a material, for example, a cushion material such as felt can be used.
The annular member 26 has a thickness along the longitudinal direction of the pipe material 12 and has an annular shape extending in contact with the circumferential direction of the outer surface of the pipe material 12.
An inner end surface 2602 where the annular member 26 faces the outer end surface 2410 of the clamp member 24 is in contact with the outer end surface 2410 of the clamp member 24.
The annular member 26 is disposed in a state where the outer peripheral surface thereof is in contact with the inner surface of the large-diameter hole 2204, and is disposed so as not to move in the radial direction of the large-diameter hole 2204.
As shown in FIG. 7, an annular plate-shaped pressing plate 28 having holes 2802 having dimensions slightly larger than the outer diameter of the pipe material 12 at both ends in the length direction of the holder body 22 is attached with screws 2804. ing.
The outer end surface 2604 of the annular member 26 located on the side opposite to the inner end surface 2602 is assembled to the holder main body 22 so as not to move in the direction away from the outer end surface 2410 in the longitudinal direction of the pipe member 12 by the pressing plate 28.

As described above, the magnetic sensor 30 is disposed at the center in the length direction of the head holder 20 so as to face the hole 2202 (see FIG. 10), and the magnetic sensor 30 is based on the magnetic field scale formed on the magnetic member 14. It detects a magnetic field and outputs a detection signal corresponding to the strength of the magnetic field. In this embodiment, a magnetoresistive element (MR sensor) is used. The magnetoresistive element changes its electric resistance in accordance with a change in magnetic field applied to the magnetoresistive element.
In the present embodiment, when the head holder 20 moves back and forth along the magnetic scale 10, the magnetic sensor 30 detects the magnetic scale and outputs a detection signal that periodically increases or decreases (for example, converts to a sine wave shape). To do.

As shown in FIG. 10, the head carrier 40 is connected to the head holder 20. In the present embodiment, the head carrier 40 is coupled to the head holder 20 via the coupling mechanism 42. In other words, the head holder 20 is supported by the head carrier 40 so that the magnetic sensor 30 cannot move in the extending direction of the pipe material 12 and can move in the direction in which the magnetic sensor 30 moves closer to and away from the outer surface of the pipe material 12.
As shown in FIGS. 5 and 8, the head carrier 40 has a case 4002 formed in a flat rectangular plate shape and a lid 4004 that closes a rectangular opening formed in the case 4002. .
The case 4002 is formed with a recess 4005 in which the base of the holder main body 22 is accommodated.
The coupling mechanism 42 includes two planar chips 44 provided at both ends in the length direction of the base portion of the holder main body 22 and two push pins 46 provided on the side surfaces of the recess 4005.
The two flat chips 44 are respectively formed with flat surfaces 4402 facing in opposite directions in the length direction.
The two push pins 46 are coaxially provided so that the extending direction thereof is parallel to the longitudinal direction of the pipe material 20, and one push pin 46 is attached to the head carrier 40 so as not to move in the extending direction, The other push pin 46 is attached to the head carrier 40 so as to be movable toward and away from the flat surface 4402, and is always urged in a direction protruding toward the flat surface 4402 by a coil spring 4602.
The head holder 20 can move in the direction of separating and approaching the outer surface of the pipe member 12 by elastically sandwiching and holding the flat surface 4402 of each planar chip 44 by the tips 4604 of the two push pins 46. Supported by the head carrier 40.
When the head holder 20 and the head carrier 40 are coupled using such a coupling mechanism 42, the pipe in a direction orthogonal to the longitudinal direction of the pipe material 12 when the head holder 20 moves along the longitudinal direction of the pipe material 12. Since the displacement (positional deviation) generated between the material 12 and the head carrier 40 can be absorbed and an excessive force can be prevented from acting between the head holder 20 and the head carrier 40, the head holder 20 and the head carrier 40 are advantageous in improving the durability.

According to such a configuration, the reference surface 2406 that can contact the outer surface of the pipe material 12 and the convex portion 2408 that presses the pipe material 12 against the reference surface 2406 by contacting the outer surface of the pipe material 12. With a very simple structure in which the head holder 20 is coupled to the magnetic scale 10 by the clamp member 24 having the above, the distance between the magnetic sensor 30 provided on the head holder 20 and the outer surface of the pipe material 12, that is, the magnetic sensor 30. And the magnetic member 14 can be kept constant.
Therefore, an accurate and stable detection signal can be obtained from the magnetic sensor 30, which is advantageous in ensuring high position detection accuracy while reducing the manufacturing cost.
Moreover, since the magnetic member 14 with the magnetic scale formed is provided inside the pipe member 12, the magnetic member 14 can be protected by the pipe member 12, and the magnetic member 14 is damaged by hitting the magnetic member 14 or the like. The magnetic scale detection operation by the magnetic sensor 30 may be affected by, for example, deterioration caused by cutting oil or the like adhering to the magnetic member 14, or dust adhering to the magnetic member 14. This is advantageous in improving the stability of the operation of the position detection apparatus 100.
Further, since the magnetic material 24 is provided in close contact with the inner surface 1202 of the pipe material 12, the magnetic flux generated by the magnetic member 14 is efficiently radiated toward the outer surface of the pipe material 12, and the surface magnetic flux density on the outer surface is increased. Therefore, it is advantageous in securing the voltage level of the detection signal detected by the magnetic sensor 36.
Further, since the annular members 26 impregnated with the lubricating oil are disposed on the outer surfaces of the two clamp members 24, the annular member 26 supplies the lubricating oil to the outer surface of the pipe material 12 and adheres to the outer surface of the pipe material 12. This is advantageous for removing the clamp member 24 smoothly with respect to the pipe member 12.
Further, when the head holder 20 is inclined with respect to the pipe material 12 due to deformation of the outer surface of the pipe material 12, the annular member 26 is pressed and deformed by the clamp member 24, so that the clamp member 24 is made elastic by the annular member 26. It is displaced so as to follow the deformation of the outer surface of the pipe material 12. As a result, the clamp member 24 can be prevented from biting into the pipe material 12, which is more advantageous in smoothly sliding the clamp member 24 relative to the pipe material 12.

Next, the configuration of the control system of the position detection apparatus 100 will be described with reference to FIG.
As shown in FIG. 1, the position detection device 100 includes an amplifier 50, a signal processing circuit 52, a comparison / determination circuit 54, a driver circuit 56, a light emitting diode (LED) 58 and the like in addition to the magnetic sensor 30.
The amplifier 50 amplifies the detection signal output from the magnetic sensor 30.
The detection circuit 52 detects a relative displacement amount of the magnetic head 30 (head holder 20) with respect to the magnetic scale 10 by processing the detection signal amplified by the amplifier 50.
The comparison / determination circuit 54 compares the magnitude of the detection signal amplified by the amplifier 50 with a predetermined reference range, determines whether the magnitude of the detection signal matches the predetermined reference range, and determines the determination result. It is output as a signal. Specifically, when the magnitude of the detection signal does not match a predetermined reference range (when the magnitude of the detection signal is not optimal), an “L” level determination signal is output, and the magnitude of the detection signal is When the predetermined reference range is met (when the magnitude of the detection signal is optimal), an “H” level determination signal is output.
If the detection signal is a signal that is converted into a sine wave, for example, the comparison determination circuit 54 determines the amplitude of the detection signal as the magnitude of the detection signal.
The predetermined reference range is set based on a range of magnitudes of the detection signals necessary for the detection circuit 52 to normally perform the relative displacement amount detection operation.

The driver circuit 56 generates a drive signal corresponding to the determination signal output from the comparison determination circuit 54 and supplies the drive signal to the light emitting diode 58.
In the present embodiment, the driver circuit 56 generates a first drive signal if the determination signal is “L” level, and generates a second drive signal if the determination signal is “H” level. .
The light emitting diode 58 can selectively perform at least two types of display different from each other. In the present embodiment, the first light and the second light having different colors are switched to emit light. Specifically, it is configured to emit red light when the first drive signal is supplied, and to emit blue light when the second drive signal is supplied. Yes. It goes without saying that the light emission color of the light emitting diode 58 may be a color other than red or blue.
As shown in FIG. 7, the light emitting diode 58 is provided so as to face outward at a portion of the case 4002 that is visible from the outside, for example, an end face that is located at one end in the length direction of the case 4002.
In the present embodiment, the light emitting diode 58 constitutes a reporting means and a display means in the scope of claims, and the comparison determination circuit 54 and the driver circuit 56 constitute a control means in the scope of claims.
As shown in FIG. 8, a printed circuit board 48 is accommodated in the case 4002 of the head carrier 40, and the amplifier 50, the comparison determination circuit 54, the driver circuit 56, and the light emitting diode 58 described above are accommodated by the printed circuit board 48. Is configured.
In addition, the case 4002 is provided with a connector 49 electrically connected to the printed circuit board 48 so that the detection signal amplified by the amplifier 50 is connected to the outside of the case 4002 via the connector 49. The signal processing circuit 52 is provided to the signal processing circuit 52.
In addition, power for operating the magnetic sensor 30, the amplifier 50, the signal processing circuit 52, the comparison determination circuit 54, the driver circuit 56, and the light emitting diode 58 is supplied from the outside of the case 4002 through the connector 49.

Next, position adjustment in the circumferential direction of the pipe member 12 with respect to the magnetic sensor 30 will be described with reference to FIG. In FIG. 2, the head holder 20 and the head carrier 40 are shown in a simplified manner in order to simplify the description. Such position adjustment is performed when an apparatus or unit for detecting the position of a moving member such as a machine tool or a printer is assembled, or when disassembly adjustment is performed on site after delivery.
As shown in FIG. 2A, when the magnetic member 14 of the magnetic scale 10 is not located at a position facing the magnetic sensor 30, that is, when the magnetic scale is not located, the magnetic sensor 30 has a magnetic member. The magnetic force lines (magnetic flux lines) radiated from the 14 magnetic graduations do not reach or very little, so even if the head holder 30 and the head carrier 40 are relatively moved along the magnetic scale 10, the magnetic sensor 30. The magnitude of the detection signal detected at is small.
In this case, since the comparison determination circuit 54 determines that the magnitude of the detection signal does not match the predetermined reference range, the comparison determination shooting circuit 54 supplies an “L” level determination signal to the driver circuit 56, thereby The driver circuit 56 supplies the first drive signal to the light emitting diode 58, and the light emitting diode 58 emits red light.
Therefore, the operator can know that the magnetic scale is not located at the position facing the magnetic sensor 30 by visually recognizing that the light emission color of the light emitting diode 58 is red.
Therefore, the operator repeats the work of rotating the pipe member 12 in the circumferential direction and then moving the head holder 30 and the head carrier 40 along the magnetic scale 10 to visually recognize the light emission color of the light emitting diode 58.
Eventually, as shown in FIG. 2B, when the magnetic graduation is located at a position facing the magnetic sensor 30, the magnetic force lines output from the magnetic graduation of the magnetic member 14 reach the magnetic sensor 30 sufficiently. When the head carrier 40 is moved along the magnetic scale 10, the magnitude of the detection signal detected by the magnetic sensor 30 increases.
In this case, since the comparison determination circuit 54 determines that the magnitude of the detection signal matches the predetermined reference range, the comparison determination circuit 54 supplies an “H” level determination signal to the driver circuit 56, thereby The circuit 56 supplies the second drive signal to the light emitting diode 58, and the light emitting diode 58 emits blue light.
Therefore, the operator can know that the magnetic graduation is located at the position facing the magnetic sensor 30 by visually recognizing that the light emission color of the light emitting diode 58 is blue, and the pipe member 12 cannot be rotated. The position adjustment in the circumferential direction of the pipe member 12 with respect to the magnetic sensor 30 is finished.

As described above, according to the present embodiment, it can be determined based on the display of the light emitting diode 58 as a notification means whether or not the magnetic scale is located at the location facing the magnetic sensor 30. Compared with the case where the position and the position of the magnetic scale are respectively measured and adjusted, this is advantageous in easily performing the operation of adjusting the position of the pipe member 12 in the circumferential direction with respect to the magnetic sensor 30.
In addition, when some abnormality occurs in the magnetic scale 10 or the magnetic sensor 30 and the magnitude of the detection signal output from the magnetic sensor 30 is reduced, and the magnitude of the detection signal does not match the predetermined reference range. Since the occurrence of the abnormality can be displayed by the light emitting diode 58, it can be easily determined whether or not the position detecting device 100 is operating normally, which is advantageous in easily performing maintenance and inspection work.
In the present embodiment, since the light emitting diode 58 is used as the display means constituting the notification means, and the light emitting diode 58 emits different colors (red and blue), the circumference of the pipe material 12 with respect to the magnetic sensor 30 is increased. Whether or not the position adjustment in the direction has been made can be immediately determined, which is advantageous in reducing the burden on the operator when adjusting the position of the pipe member 12 in the circumferential direction with respect to the magnetic sensor 30.

In the present embodiment, the case where the two types of display are the first light and the second light of the light emitting diode 58 that are different from each other has been described. However, the configuration of the light emitting diode 58 and the notification form thereof are described here. It is not limited to.
For example, two light emitting diodes that emit light having different emission colors may be provided, and two different types of display may be performed by switching the two light emitting diodes to emit light.
Also, two different types of display may be performed depending on whether a single light emitting diode is turned on or off.
Further, the display means is not limited to the light emitting diode, and various conventionally known display devices such as a lamp and a liquid crystal display device can be adopted. However, when the light emitting diode is used as in the present embodiment, Is advantageous in that it consumes less power and occupies less space.
In addition, the notification means is not limited to a visually observable display means, and may be composed of audio output means such as a audible speaker or a buzzer, and the two types of notification forms may be different from each other. Good.
As the two types of voice forms, for example, a voice having a high frequency and a voice having a low frequency, a continuous voice and an intermittent voice, or a language indicating completion and incomplete adjustment can be employed. Or you may make it perform two types of alerting | reporting mutually different by presence or absence of an audio | voice.
The location of the notification means is arbitrary, but if the light emitting diode 58 as the notification means is provided in the head carrier 40 located in the vicinity of the magnetic scale 10 as in this embodiment, the light emitting diode 58 is magnetic. It is advantageous because it can be easily determined that the sensor 30 is for determining whether or not the magnetic scale is positioned at an appropriate position.
Further, in the present embodiment, the case where the control unit is configured by the comparison determination circuit 54 and the driver circuit 56 has been described, but the control unit is changed according to the configuration of the notification unit.
Further, in the present embodiment, the case of a so-called built-in type position detection device in which the magnetic sensor 30 is provided in the head holder 20 slidably connected to the pipe material 10 has been described. The head holder 20 that supports the magnetic sensor 30 is not slidably supported by the pipe material 10 and is provided separately from the pipe material 10 as shown in FIG. Of course, the present invention can also be applied to other position detection devices.
In the embodiment, the case where a rubber magnet is used as the magnetic member 14 has been described. However, the magnetic member is not limited to this, for example, a plastic magnet, a magnetic material coating material, a rare earth magnetic material, a ferrite Any material that can be magnetized, such as a magnetic material, may be used.
Needless to say, the magnetic member 14 may be disposed by pouring a powdery magnetic material into the space inside the pipe member 12 and forming it into a desired shape.
In the embodiment, the case where the pipe member 12 has a cylindrical cross section has been described. However, various hollow cross-sectional shapes such as a rectangular frame and a polygonal frame can be adopted as the cross section of the pipe member 12.

It is a block diagram which shows the structure of the control system of the position detection apparatus of 1st Embodiment. (A), (B) is explanatory drawing which shows the display of the light emitting diode of the position detection apparatus of 1st Embodiment. It is a block diagram of the position detection apparatus of 1st Embodiment. It is AA sectional view taken on the line of FIG. It is a front view of a head holder and a head carrier. It is A arrow directional view of FIG. FIG. 6 is a view taken in the direction of arrow B in FIG. 5. It is a front view of a head holder and a head carrier. It is BB sectional drawing of FIG. It is CC sectional view taken on the line of FIG. (A) is a top view of a clamp member, (B) is a B arrow view of (A). It is explanatory drawing which shows the example of a separate type position detection apparatus.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Magnetic scale, 12 ... Pipe material, 14 ... Magnetic member, 30 ... Magnetic sensor, 54 ... Comparison judgment circuit, 56 ... Driver circuit, 58 ... Light emitting diode, 100 ... Position detection apparatus.

Claims (6)

A cylindrical pipe material and a part of the inner surface of the pipe material in the circumferential direction are attached and extend linearly along the longitudinal direction of the pipe material, and a magnetic scale is formed along the extending direction. A magnetic scale having a magnetic member;
A head holder that is slidably coupled to the magnetic scale, and is disposed so as to be capable of reciprocating linear movement in the extending direction of the magnetic scale;
Said integral head holder and movably provided along the longitudinal direction of the magnetic scale, a detection sensor for generating a detection signal by detecting the magnetic marks,
A notification means capable of selectively performing two types of notification forms different from each other;
Control means for switching the notification mode of the notification means based on the magnitude of the detection signal output from the detection sensor;
A head carrier containing the control means and coupled to the head holder;
In the head holder, two planar chips provided at both ends in the longitudinal direction of the magnetic scale and formed with flat surfaces facing the both ends, respectively, projecting from the side surface of the head carrier, and on the flat surfaces of the planar chip Two push pins whose tips contact each other, and a biasing member that biases at least one of the two push pins toward the flat surface of the planar chip, and connects the head holder and the head carrier. A coupling mechanism to
A position detecting device characterized by comprising:   The control means compares the magnitude of the detection signal with a predetermined reference range, determines whether or not the magnitude of the detection signal matches the predetermined reference range, and switches the notification mode of the notification means. The position detection apparatus according to claim 1, wherein the position detection apparatus is configured to perform the determination based on the determination result.   2. The position detection apparatus according to claim 1, wherein the notification unit is configured by a visually observable display unit, and the two types of notification modes are two different types of display.   The informing means is composed of visually observable display means, the two kinds of informing forms are two kinds of different displays, and the two kinds of displays are the first light and the second light having different colors And the control means causes the display means to emit light with the first light when the magnitude of the detection signal does not match a predetermined reference range, and the magnitude of the detection signal is the predetermined magnitude. The position detecting device according to claim 1, wherein the display means is configured to emit light by the second light when the reference range is met.   5. The position detecting device according to claim 4, wherein the display means is composed of a light emitting diode capable of emitting light by switching between first light and second light having different colors.   2. The position detecting device according to claim 1, wherein the informing means is constituted by an audible sound output means, and the two kinds of informing forms are two kinds of sound forms different from each other.

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