JP2004132843A - Location detection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately set the location of a sensor by a simple operation. <P>SOLUTION: The device is provided with a scale 5 having a location signal, a substrate 9 arranged oppositely to the location signal formation side of the scale, a sensor holder 11 having a sensor 10 detecting the location signal and fixed to the scale 5 side of the substrate 9, and a detector 6 having an adjusting member 12 adjusting an interval of the sensor 10 opposing to the scale 5. Outside areas 19a and 19b formed by dividing the sensor holder 11 into a pair of grooves 17A and 17B are pressed by the adjusting member 12 to accurately adjust the interval of the sensor 10 opposing to the scale 5. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a position detection device that is attached to a main body device such as a machine tool or an industrial robot having a movable part and detects a movement amount and a movement position of the movable part.
[0002]
[Prior art]
2. Description of the Related Art A main body device such as various machine tools and industrial robots is provided with a position detecting device for detecting a moving amount and a moving position of a movable portion such as a table. The position detecting device has a long scale portion provided with a position signal indicating a moving amount and a moving position of the movable portion, and a sensor for detecting the position signal, and the sensor faces a position signal forming surface of the scale portion. And a detection unit that is assembled to perform In the position detecting device, the sensor is positioned with respect to the scale portion at a predetermined interval between the sensor and the position signal forming surface of the scale portion, and is combined.
[0003]
In the position detection device, the detection unit is connected to a movable unit or a fixed unit of the main body device by an appropriate connection mechanism. In the position detection device, for example, when the detection unit is connected to the movable unit, the sensor slides along the position signal forming surface of the scale unit along with the movement operation of the movable unit, and the sensor moves from the fixed point of the scale unit. A position signal at a predetermined position is detected. The position detection device outputs the position information from the detection unit to the main device, and controls the moving operation of the movable unit. In the position detection device, the distance between the sensor and the scale unit is precisely set to a predetermined distance so that the sensor can accurately detect the position signal of the scale unit and perform appropriate control of the movement of the main device.
[0004]
[Problems to be solved by the invention]
In the conventional position detecting device, the sensor is directly attached and fixed to the surface of the detecting unit facing the scale unit, or is attached to a sensor supporting member that supports the sensor, and the sensor supporting member faces the scale unit of the detecting unit. Directly attached to the surface to be fixed. For this reason, in the position detecting device, when fixing the sensor or the sensor supporting member to the detecting portion, the sensor or the sensor supporting member is fixed by using a jig or the like such that the facing distance between the scale portion and the sensor becomes a predetermined facing distance. After being temporarily fixed to the detection unit once in the positioned state, it is permanently fixed to the detection unit.
[0005]
In the position detection device, since the jig or the like is removed when the main fixing is performed, the position of the sensor or the sensor supporting member may be shifted, and the distance between the sensor and the scale may not be accurately set. In the position detection device, since the distance between the sensors facing the scale unit is not precisely set to a predetermined distance, it is difficult to accurately detect the position signal of the scale unit. Further, in the position detection device, since the moving position of the movable portion cannot be accurately detected, there is a problem that the position of the movable portion is not properly controlled. Further, in the position detection device, every time a position shift of the sensor or the sensor support member occurs, a troublesome operation of re-adjusting the position of the sensor or the sensor support member is required, and there is a problem that the working efficiency is reduced. .
[0006]
Therefore, an object of the present invention is to provide a position detecting device that can precisely set the position of a sensor with respect to a scale by a simple operation.
[0007]
[Means for Solving the Problems]
A position detection device according to the present invention that achieves the above-described object includes a detection unit that moves relative to a scale unit provided with a position signal in accordance with a moving operation of a movable unit of a main device, and detects the position signal. Is provided. The detection unit is mounted on a surface of the substrate facing the position signal forming surface of the scale unit, and is mounted on a surface of the substrate facing the scale unit, and a sensor for detecting a position signal is mounted on the substrate facing the position signal forming surface. It has a sensor holder and an adjusting member that adjusts the distance between the sensor and the scale section by pressing the sensor holder from the substrate side. In the sensor holder, a pair of concave grooves is formed in the width direction so as to sandwich the sensor mounting region where the sensor is mounted, and the outer region of the sensor mounting region divided and formed by these concave grooves is adjusted. Pressed by the member.
[0008]
According to the position detection device of the present invention configured as described above, the detection unit moves relative to the scale unit by moving the movable unit of the main unit relative to the fixed unit. In the position detection device, a sensor attached to a substrate of the detection unit detects a position signal of the scale unit, outputs position information to a main device, and performs position control of the movable unit.
[0009]
In the position detection device, an operation of precisely adjusting the facing distance between the position signal forming surface of the scale section and the sensor is performed via the sensor holder by pressing the sensor holder with the adjusting member. In the position detection device, the adjustment member presses the outer region of the sensor mounting region formed by being partitioned by the pair of concave grooves provided in the sensor holder, so that the bending of the sensor holder is absorbed by the pair of concave grooves, The occurrence of bending in the sensor mounting area is suppressed. According to the position detecting device, the simple operation by the adjusting member and the pair of concave grooves of the sensor holder cause the sensor mounting area to move in a state in which the entire sensor mounting area is parallel to the position signal forming surface, thereby forming the position signal of the scale section. The distance between the surface and the sensor is precisely set.
[0010]
Therefore, according to the position detecting device, in a state where the facing distance between the sensor and the position signal forming surface of the scale unit is accurately maintained over the entire area, the detecting unit is moved along with the moving operation of the movable unit of the main device. The sensor detects a position signal by moving relative to the scale unit. According to the position detecting device, the position detection and the position control of the movable portion are precisely performed by detecting the position signal by the precisely set sensor.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. As shown in FIGS. 1 and 2, a position detection device 1 illustrated in the drawings as an embodiment includes a scale unit 5 attached to a fixed unit 2 of a main device 4 having a fixed unit 2 and a movable unit 3, A detection unit 6 attached to the movable unit 3 of the main device 4. The movable section 3 of the main device 4 is a machining table or a bite table of various machine tools, industrial machines or precision machines, and performs a precise movement operation.
[0012]
In the position detecting device 1, a detecting unit 6 is assembled to a scale unit 5, and a connecting mechanism 7 provided at one end of the detecting unit 6 is connected to a carrier 8 connected to the movable unit 3. 3 is transmitted to the detection unit 6 via the coupling mechanism 7 and the carrier 8. In the position detecting device 1, the detecting unit 6 moves the scale unit 5 with the moving operation of the movable unit 3 transmitted to the detecting unit 6. The position detection device 1 feeds back position information detected by the movement of the detection unit 6 to the movable unit 3 and controls the movement operation of the movable unit 3.
[0013]
The scale section 5 is formed in a long shape, and optical, magnetic or mechanical signals indicating positional information such as the moving amount and the moving position of the movable section 3 of the main device 4 are transmitted to the first main surface. The first main surface is formed as a position signal forming surface 5a. The scale portion 5 is made of iron, stainless steel, or the like, has a length sufficient to cover the entire area in the length direction, and is housed in a case member formed in a channel shape with an open bottom portion. I have. The case member has an attachment portion for attachment and fixation to the fixation portion 2 of the main device 4 on one side surface, although details are omitted.
[0014]
The detection unit 6 is provided with a substrate 9 movably disposed facing the position signal forming surface 5 a of the scale unit 5 and a sensor 10 for detecting a position signal of the scale unit 5. , And an adjusting member 12 for adjusting an interval Δx between the sensor 10 and the scale section 5 as will be described later in detail.
[0015]
As shown in FIGS. 2 and 3, the detection unit 6 is combined with the substrate 9 precisely positioned with respect to the scale unit 5 as described in detail later, and the sensor holder 11 fixed to the substrate 9. Is precisely positioned by the adjustment member 12, so that the sensor 10 is precisely set with respect to the position signal forming surface 5 a of the scale section 5 via the sensor holder 11. The detecting unit 6 detects a position signal by sliding the substrate 9 to which the sensor holder 11 is fixed on the position signal forming surface 5a of the scale unit 5 in accordance with the moving operation of the movable unit 3 of the main device 4. At 10, the movement amount and the movement position of the movable unit 3 are output to the main device 4.
[0016]
The substrate 9 is formed in a rectangular shape, and has a recess 13 in which the sensor holder 11 is fixed on a surface facing the scale portion 5. A through hole 14 a through which the screw 14 for fixing the sensor holder 11 passes is formed in the substrate 9 at a position near both ends in the width direction of the storage recess 13. The substrate 9 has a screw hole 12a into which the adjusting member 12 is screwed, and a hole 16 formed in the sensor holder 11 to be described later and fitted with a convex portion 15 serving as a rotation fulcrum for adjusting the angle of the sensor 10 in the rotation direction. Is formed.
[0017]
A plurality of guide rollers 18a to 18e are provided on the substrate 9 so as to be freely slidable in the longitudinal direction of the scale section 5 near both ends of the scale section 5 in the longitudinal direction and at positions facing the lower edge of the scale section 5, respectively. Has been. The substrate 9 is transferred to the scale unit 5 by the guide rollers 18a to 18e rolling on the position signal forming surface 5a with the movement of the movable unit 3 of the main unit 4 via the coupling mechanism 7 and the carrier 8. On the other hand, a smooth sliding movement is performed without vertical vibration, horizontal vibration, or the like.
[0018]
As shown in FIG. 4, the sensor holder 11 is formed in a substantially rectangular shape, and a central area is configured as a sensor mounting area 10 a to which the sensor 10 for detecting the position signal of the scale section 5 is adhered and fixed. ing. The sensor 10 has one end connected to the flexible cable 4a connected to the output unit of the main device 4, and outputs the detected position signal to the output unit as position information.
[0019]
A pair of concave grooves 17A and 17B are formed in the sensor holder 11 in the width direction on the surface facing the scale portion 5 so as to sandwich the sensor mounting region 10a. When adjusting the position of the sensor 10 with respect to the scale portion 5, the sensor holder 11 presses the opposing outer regions 19a and 19b of the sensor mounting region 10a divided by the concave grooves 17A and 17B by the adjusting member 12. In the sensor holder 11, when the outer regions 19a, 19b are pressed by the adjusting member 12 from the substrate 9 side, distortions and flexures generated in the outer regions 19a, 19b are absorbed by the concave grooves 17A, 17B. 10a is prevented from being bent or distorted. Therefore, according to the sensor holder 11, the sensor 10 approaching while maintaining a state parallel to the scale portion 5 is moved and adjusted in parallel to the position signal forming surface 5 a of the scale portion 5. become. Note that the shape of the concave grooves 17A and 17B may have a function of absorbing flexure and distortion of the outer regions 19a and 19b, and is not limited to the concave shape as shown in FIG. Each may be constituted by a plurality of grooves.
[0020]
In the sensor holder 11, screw holes 14b for screwing screws 14 to be fixed to the substrate 9 are provided in the vicinity of both ends in the width direction, and a convex portion 15 fitted to a hole 16 formed in the substrate 9 is attached to the sensor holder. It is formed substantially at the center of one end of the region 10a. The convex portion 15 and the hole portion 16 serve as a fulcrum of rotation of the sensor holder 11 with respect to the substrate 9 in a direction indicated by an arrow A in FIG. I do. The angle of the sensor holder 11 in the rotation direction of the sensor 10 with respect to the scale unit 5 is adjusted in a state where the protrusion 15 is fitted into the hole 16. Note that the swing mechanism only needs to be able to adjust the angle in the rotation direction with respect to the scale portion 5. For example, the convex portion 15 is provided on one of the substrate 9 and the sensor holder 11, and the convex portion 15 is fitted on the other. A hole 16 may be provided.
[0021]
The adjusting member 12 is screwed into the screw hole 12 a from the outside of the substrate 9, and the tip thereof comes into contact with the concave groove 17 </ b> A, 17 </ b> B of the sensor holder 11 stored in the storing recess 13 of the substrate 9 at a position facing the sensor 10. Is installed as follows. The adjusting member 12 is, for example, a screw having a spiral groove formed therein, and is screwed into the screw hole 12 a so that the tip presses the sensor holder 11 so that the adjusting member 12 can be freely adjusted in the direction of approaching the scale portion 5. Consists of members. The adjusting member 12 adjusts the interval Δx and the inclination of the sensor 10 facing the scale unit 5.
[0022]
As shown in FIG. 5, the sensor holder 11 is pressed toward the scale portion 5 via the adjustment member 12, so that the sensor holder 11 is bent or distorted so as to be entirely curved in an arc shape. , 17B are formed to absorb bending and distortion, and the occurrence of bending and distortion in the sensor mounting region 10a is suppressed. Therefore, the sensor holder 11 brings the sensor 10 close to the scale portion 5 in a state of being parallel to the scale portion 5 via the sensor attachment region 10a, and reduces the facing distance Δx between the scale portion 5 and the sensor 10.
[0023]
The adjustment member 12 is loosened in the outward direction, so that the sensor holder 11 reversibly returns to the original state. Therefore, the adjustment member 12 is separated from the scale portion 5 of the sensor 10 in parallel with the scale portion 5 and the sensor 10. Are made wider. The adjusting member 12 is applied with a force in the direction of returning to the external direction by the elastic stress of the sensor holder 11 generated when the adjusting member 12 is pressed in the direction of the scale portion 5, so that the effect of preventing loosening can be obtained. As shown in FIG. 3, the adjusting member 12 is provided at three points in the outer regions 19a and 19b. However, if the opposing distance Δx and the inclination of the sensor 10 with respect to the scale section 5 can be adjusted, two points or four points are provided. The above may be provided.
[0024]
The position detection device 1 precisely adjusts the distance Δx and the inclination of the sensor 10 facing the scale unit 5 as follows. In the position detection device 1, the angle of the sensor holder 11 in the rotation direction is adjusted by rotating the sensor holder 11 to which the sensor 10 is adhered with the projection 15 and the hole 16 as a rotation fulcrum. The position detection device 1 adjusts the interval Δx and the inclination of the sensor 10 facing the scale unit 5 to predetermined intervals and inclinations, and tightens a plurality of screws 14 in a set state, so that the sensor holder 11 13 is fixed.
[0025]
In the position detection device 1, in setting the rotation angle of the sensor holder 11 and the interval Δx and the inclination of the sensor 10 facing the scale unit 5, a predetermined rotation angle, a predetermined rotation angle, Adjust to spacing and tilt. In the position detecting device 1, the displacement generated when the sensor holder 11 is fully fixed to the substrate 9 is adjusted by the adjusting member 12 while observing the output waveform indicating the amount of pressing of the adjusting member 12 by a predetermined amount. It is precisely adjusted to have the interval Δx and the inclination. In the position detecting device 1, by adjusting the sensor holder 11 with the adjusting member 12, the interval Δx and the inclination of the sensor 10 facing the scale unit 5 can be easily and precisely set to predetermined intervals and inclinations.
[0026]
According to the position detection device 1 described above, the displacement that occurs when the sensor holder 11 is permanently fixed to the substrate 9 is reduced by a simple operation using the adjustment member 12 and the pair of concave grooves 17A and 17B formed in the sensor holder 11. With the sensor mounting area 10a being parallel to the position signal forming surface 5a of the scale section 5, the facing distance Δx and the inclination are adjusted, and are precisely set to the predetermined facing distance Δx and the inclination. Therefore, according to the position detecting device 1, the sensor 10 precisely maintains the facing distance Δx and the inclination with the position signal forming surface 5 a of the scale part 5 at the predetermined facing distance and inclination in accordance with the moving operation of the movable part 3. The slide movement is performed in the state of being performed, and the position signal is detected. In the position detection device 1, the position detection and position control of the movable unit 3 are precisely performed based on the position information detected by the precisely held sensor 10.
[0027]
In the position detection device 1, the scale unit 5 is attached to the fixed unit 2 of the main device 4, and the detection unit 6 is attached to the movable unit 3. However, the detection unit 6 is attached to the fixed unit 2, and the movable unit 3 is attached to the fixed unit 2. The scale unit 5 may be attached, and the scale unit may slide with respect to the detection unit 6. In the position detection device 1, the position information detected by the detection unit 6 is fed back to the movable unit 3 to control the moving operation of the movable unit 3. For example, the position information is transmitted to an appropriate display device. Alternatively, the position of the movable section 3 may be displayed.
[0028]
【The invention's effect】
As described in detail above, the position detection device according to the present invention adjusts the displacement generated when the sensor holder is permanently fixed to the substrate by the adjustment member, so that the precise setting of the interval between the sensor and the scale portion can be easily performed. It becomes. Also, in the position detecting device, since the bending of the sensor mounting area is suppressed by the pair of concave grooves provided in the sensor holder, the sensor is parallel to the scale portion, and a change in the position signal due to the inclination of the sensor is prevented. And the detection becomes highly accurate. Therefore, in the position detecting device, since the interval and the inclination of the sensor with respect to the scale section are precisely set, the detection of the position signal becomes highly accurate and stable, and the reliability of position detection and position control of the movable section is improved. .
[Brief description of the drawings]
FIG. 1 is a schematic diagram of a state in which a position detecting device according to the present invention is provided in a main device.
FIG. 2 is a cross-sectional view of a detection unit of the position detection device.
FIG. 3 is a rear view of a detection unit of the position detection device.
FIG. 4 is a perspective view of a sensor holder of the position detecting device.
FIG. 5 is a cross-sectional view of a main part for explaining a position adjustment operation of a sensor with respect to a scale unit in the position detection device.
[Explanation of symbols]
Reference Signs List 1 position detecting device, 5 scale section, 6 detecting section, 7 connecting mechanism, 9 substrate, 10 sensor, 10a sensor mounting area, 11 sensor holder, 12 adjusting member, 12a screw hole, 13 housing recess, 14 screw, 14a through hole , 14b screw hole, 15 convex portion, 16 hole portion, 17a, 17b concave groove, 18a-18e guide roller, 19a, 19b outside region

Claims (2)

Along with the moving operation of the movable unit of the main device, a relative movement is performed with respect to the scale unit provided with the position signal, and a detection unit that detects the position signal is provided.
The detection unit is mounted on a surface of the substrate that faces the position signal forming surface of the scale unit, and is attached to a surface of the substrate that faces the scale unit, and detects the position signal while facing the position signal forming surface. A sensor holder to which a sensor to be detected is attached, and an adjusting member that adjusts an interval between the sensor and the scale portion by pressing the sensor holder from the substrate side,
A pair of concave grooves are formed in the sensor holder in the width direction so as to sandwich the sensor mounting region where the sensor is mounted, and an outer region of the sensor mounting region divided and formed by these concave grooves is the adjusting member. The position of the sensor mounting area is suppressed by the concave groove and the distance between the sensor and the position signal forming surface of the scale section is adjusted. . The board and the sensor holder are provided with a swing mechanism for swingably supporting the sensor holder with respect to the board,
2. The position detection according to claim 1, wherein an angle adjustment of the sensor with respect to a position signal forming surface of the scale is performed by rotating the sensor holder with respect to the substrate by the swing mechanism. apparatus.

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