JPH08262048A - Apparatus for mounting rotation detector - Google Patents

Abstract

PURPOSE: To position a rotation detector accurately by a method wherein a contact surface of a mounting plate is made to butt against reference surface of a support body, and pressed against the reference surface to fix the support body on the mounting plate. CONSTITUTION: A jig for positioning with the dimensions and shape thereof the same as those of a mounting part 16 of a rotor 14 and a spindle head 20 is prepared and a sensor 12 is adjusted and positioned at the optimum position with respect to a rotor 14 on the symmetry axis of the mounting plate to be fixed on the mounting plate 10 by fixing members 10a and 10b. With the mounting plate 10 pressed against a reference surface 10b, a bolt is tightened to fix the sensor 12 at the optimum position with respect to the rotor 14. When the bolt is turned in the direction for tightening, a washer turns in the direction of increasing the radius of a retaining part together with the bolt to press a contact surface against the reference surface 16b. In addition, this operation is executed simultaneously for a pair of bolts for fixing the mounting plate 10 on the mounting part 16. This device accurately positions the sensor 12 at the optimum position with respect to the rotor 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for mounting a rotation detector such as a rotary encoder.

[0002]

2. Description of the Related Art Conventionally, a drive motor such as an AC servo motor has been used for driving a robot arm of an industrial robot and rotating a ball screw or a spindle of a machine tool. A rotation detector is used to control the drive motor to detect the rotation of the rotation axis of the drive motor. Although there are various types of rotation detectors, a rotation detector provided at the end of the main shaft of the machine tool shown in FIG.

In FIG. 6, a spindle 106 is a spindle head 100.
Is rotatably supported by a bearing (not shown) such as a ball bearing. The rotation detector that detects the rotation of the main shaft 106 is the detection target 1 fitted and fixed to the main shaft 106.
08, and the detection part 110 attached to the spindle head 100 and detecting the rotation of the detected object 108. Although not shown in detail in FIG. 6, the detected object 108 is an annular member having a plurality of teeth formed on its outer peripheral surface. The detection unit 110 is a magnetic sensor, and is connected to a control device (not shown) of a machine tool via an electric wire 110a. Detector 11
0 is arranged so as to face the outer peripheral surface of the detected object 108. When the main shaft 106 rotates, the magnetic field between the detection unit 110 and the teeth of the detected unit 108 changes, and the detection unit 110
Detects the change in the magnetic field and transmits an electric signal corresponding to the change to the control device of the machine tool. Since the change in magnetism is a minute change, the detection unit 110 must be positioned very accurately so as to be close to the side surface of the detected unit 108.

The detector 110 includes a fixing member 112 and a screw 1.
It is attached to the ring-shaped mounting plate 102 by 14 and. The mounting plate 102 is fixed to the mounting portion 104 of the spindle head 100 by inserting a bolt (not shown) screwed into a bolt hole formed in the spindle head 100 into the hole portion 102a. The mounting portion 104 has an anchoring portion or a reference surface 104a which is an outer peripheral surface that is precision machined concentrically with the main shaft 106. The inner peripheral surface of the annular mounting plate 102 is the reference surface 10
Precision-machined with an inner diameter almost equal to the outer shape of 4a,
The mounting plate 102 is accurately positioned by fitting the inner peripheral surface of the mounting plate 102 and the reference surface 104a.
If the detecting section 110 is accurately positioned in advance with respect to the mounting plate 102, the detecting section 110 can be accurately positioned with respect to the detected section 108.

[0005]

According to the above-described mounting device of the rotation detector according to the prior art, since the detecting portion 110 is attached to the annular mounting plate 102, it is necessary to replace or adjust the detecting portion 110. When the mounting plate 102
In FIG. 6, all the mechanical elements arranged above the mounting plate 102 must be removed in order to remove. This problem can be solved if the mounting plate 110 is a semicircular plate or a circular arc-shaped plate member smaller than the semicircular plate so as to be removable in the direction perpendicular to the main shaft 106.
With the configuration of 10 as described above, it is difficult to press the inner peripheral surface of the arc-shaped mounting plate tightly against the reference surface 104a of the mounting portion 104 and accurately position the detection surface.
A problem arises in that it is difficult to accurately position the object with respect to the detected part 108.

An object of the present invention is to solve the above-mentioned problems of the prior art, and it is an object of the present invention to provide a rotation detector mounting device capable of accurately positioning the rotation detector and easily removable. Has an aim.

[0007]

According to the present invention, there is provided a rotation comprising a detection part fixed to a rotary shaft rotatably supported by a support, and a detection part detecting the operation of the detection part. In a rotation detector attachment adjusting device for positioning and fixing the detection part of the detector on a support, a detection part having a reference surface formed on the support and an abutment surface formed in a complementary shape to the reference surface is provided. A gist of a mounting device including a mounting plate that holds the mounting plate, and a mounting plate pressing contact fixing means that fixes the mounting plate to a support body while pressing the mounting plate against the reference surface in a direction substantially perpendicular to the rotation axis on the contact surface. .

[0008]

[Operation] The abutment surface of the mounting plate is abutted against the reference surface of the support,
The mounting plate is fixed to the support body while pressing the contact surface against the reference surface by the mounting plate pressing contact fixing means.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the accompanying drawings. In FIG. 1, a spindle 18 as a rotary shaft is rotatably supported by a spindle head 20 as a support through bearings 20a and 20b. A for the spindle 18
A rotor 24 of a drive motor such as a C servo motor is fitted and a stator 22 fixed to the spindle head 20 is arranged so as to surround the rotor 24. The main shaft 18 rotates by exciting the drive motor.

A rotation detector for detecting the rotation of the main shaft 18 is arranged above or outside the drive motor of the main shaft 18. The rotation detector is fitted on the main shaft 18,
It is provided with a fixed rotating body 14 as a detected portion and a sensor 12 as a detecting portion. As shown in the drawing, the rotating body 14 is an annular member that is fixed concentrically with the rotating shaft 18, and has a plurality of teeth formed of concavities and convexities that extend parallel to the rotating axis on its side surface 14a (FIG. 2 (a)
reference). In the present embodiment, the sensor 12 is a magnetic sensor, which is arranged so as to face the side surface 14a of the rotating body 14 and is connected to a control device (not shown) of a machine tool via an electric wire 12a. The sensor 12 detects a change in the magnetic field between the rotating body 14 and the sensor 12 when the main shaft 12 rotates, and outputs a signal corresponding to the change in the magnetic field to the control unit of the machine tool. The number of revolutions of the spindle 12 is detected by counting the change in the output signal from the sensor 12. The sensor 12 is fixed to the spindle head 20 via the mounting plate 10. The mounting plate 10 is fixed to the spindle head 2 by a fixing means described later.
It is attached to the mounting portion 16 of 0.

Referring to FIG. 4, a mounting portion 16 is formed on the spindle head 20. The mounting portion 16 is formed in an annular shape concentric with the main shaft 18, and has an annular rib 16 protruding from the upper end.
It has a and a mounting surface 16c. An outer peripheral surface 16b of the annular rib 16a is formed as a reference surface precisely machined so as to be concentric with the main shaft 18, and a mounting surface 16c is formed perpendicular to the main shaft 18. The mounting surface 16c is provided with a mounting hole formed by arranging the large hole 16e and the small hole concentrically and axially. A female screw 16d is formed on the inner peripheral surface of the small hole.

As shown in FIG. 3, the mounting plate 10 has a main shaft 18
Is symmetrical arcuate plate member about the objective axis O that passes through the central axis O _S of the reference plane 16b of the mounting portion 16
The contact surface 10e that contacts with is precisely processed. Adjustment holes are formed through the vicinity of both ends 10f of the mounting plate 10. The adjustment hole is composed of a circular engagement hole portion 10c opened on the upper surface of the mounting plate 10 and an elongated hole portion 10d opened on the lower surface.
The engaging hole portion 10c and the elongated hole portion 10d have respective central axes O ₁ ,
O ₂ is formed so as to be offset in a direction parallel to the target axis O. More specifically, the adjustment hole is the elongated hole portion 10.
The central axis O _{2 of} d is formed so as to approach the end 10f of the mounting plate 10 in parallel with the central axis O ₁ of the engaging hole 10c. In particular, the long hole portion 10d is attached to the mounting plate 1
When 0 is properly mounted on the mounting portion 16 of the spindle head 20, its central axis O ₂ is positioned so as to coincide with the central axis of the mounting hole of the mounting portion 16.

The mounting plate 10 has bolts 2 as shown in FIG.
It is fixed to the mounting portion 16 of the spindle head 20 by 6 and a washer 28. In this embodiment, the bolt 26 is a right-handed bolt having a hexagonal hole that can be engaged with a hexagonal wrench 32 for fastening the bolt. The washer 28 has a hexagonal columnar head portion 28a that can be engaged with the spanner 30, an engagement portion 28b that engages with the engagement hole portion 10c of the adjustment hole of the mounting plate 10, and an adjustment hole of the mounting plate 10. A through hole 28d having a leg portion 28c inserted into the elongated hole 10d of FIG.
Are formed.

The engaging portion 28b has a continuous radius from the starting point 28e to the ending point 28f on the outer surface in the direction opposite to the fastening direction of the bolt 26 (counterclockwise direction because the bolt 26 is a right-hand screw in this embodiment). It is preferably formed along the Archimedes curve so as to be substantially larger. Engagement part 28b
Is formed to be equal to or slightly larger than the inner diameter of the engaging hole portion 10c of the mounting plate 10 at the end point 28f where the radius becomes the maximum value. The leg portion 28c is formed in a substantially cylindrical shape, and preferably, when the mounting plate 10 is attached to the mounting portion 16 of the spindle head 20, as shown in FIG. It is formed to have a length that penetrates to reach the large hole portion 16e of the mounting portion 16 and does not contact the bottom surface of the large hole portion 16e. The leg 28c has a large hole 16e
The washer 28 has a diameter substantially equal to the inner diameter of the washer 28 and acts as a rotation axis of the washer 28.

As will be understood from the following description,
The bolt 26, the washer 28, and the adjusting hole of the mounting plate 10 form a pressing and fixing means for the mounting plate 10.

Next, the operation of the mounting device will be described. First,
A positioning jig having the same size and shape as the rotary shaft 18 of the spindle end portion to be actually mounted, the rotating body 14, and the mounting portion 16 of the spindle head 20 is prepared, and the sensor 12 is mounted on the target shaft of the mounting plate 10. It is previously adjusted and positioned on the O at an optimum position with respect to the rotating body 14 and fixed to the mounting plate 10 by the fixing members 10a and 10b.

Next, the mounting plate 1 on which the sensor 12 is mounted
0 is inserted into the mounting portion 16 of the spindle head 20 in the direction perpendicular to the spindle 18. The head 28a of the washer 28 is placed outside and the washer 28 is inserted into the adjustment hole of the mounting plate 10. At this time,
The leg portion 28c of the washer 28 is engaged with the elongated hole 10d of the mounting plate 10, and the engaging portion 28b is engaged with the engaging hole portion 10c of the mounting plate 10. The bolt 26 is inserted into the through hole 28d of the washer 28 and screwed into the female screw 16d of the mounting portion 16 (FIG. 2 (b)).
reference). The hexagon wrench 32 is engaged with the hexagonal hole of the bolt 26 to lightly tighten the bolt 26. At this time, the long hole 10d
Is long in the direction of the target axis O, the mounting plate 1
0 is temporarily fixed so as to be movable in the direction of the target axis O. Next, the spanner 30 is engaged with the head portion 28a of the washer 28 to rotate the bolt 26 in the fastening direction, that is, in the clockwise direction in FIG. Since the leg portion 28c of the washer 28 is inserted into the large hole portion 16e of the mounting hole of the mounting portion 16, the washer 28
Rotates about the leg 28c.

The center axis O ₁ of the engaging hole portion 10c of the mounting plate 10 is larger than the center axis O ₂ of the elongated hole portion 10d.
Since it is offset in the direction away from the end portion 10f of 0, when the washer 28 is rotated, the engaging portion 28b comes into contact with the inner peripheral surface of the engaging hole portion 10c which is close to the end portion 10f of the mounting plate 10. To do. In addition, the engaging portion 28b of the washer 28
Is formed so that the radius continuously increases in the counterclockwise direction from the start point 28e to the end point 28f, and therefore, by rotating the washer 28 in the clockwise direction, the mounting plate 10 at the engaging portion 28b. The radius of the adjusting hole at the contact point with the circular engaging hole portion 10c gradually increases. Therefore,
By rotating the washer 28 in the clockwise direction, the mounting plate 10 is gradually and strongly pressed by the contact between the inner peripheral surface of the engaging hole portion 10c and the side surface of the engaging portion 28b of the washer 28.
In this way, by rotating the washer 28 in the clockwise direction, the mounting plate 10 is attached to the mounting portion 16 at the contact surface 10e.
It is pressed against the reference surface 16b of and is accurately positioned in the mounting portion 16.

Then, the bolt 26 is tightened while the mounting plate 10 is pressed against the reference surface 16b, whereby the sensor 1
2 is fixed in an optimum position with respect to the rotating body 14. As described above, since the engaging portion 28b of the washer 28 is formed so that the radius increases in the direction opposite to the rotation direction in which the bolt 26 is fastened, rotating the bolt 26 in the fastening direction causes the washer 28 to engage. In the direction in which the radius of the joint 28e increases, the bolt 2
It rotates together with 6, and the contact surface 10e is strongly pressed against the reference surface 16b. Further, in the above operation, the mounting plate 10 is attached to the mounting portion 16
It goes without saying that it is desirable to carry out simultaneously with a pair of bolts 26 which are fixed to each other. Thus, the sensor 12 is accurately positioned at the optimum position with respect to the rotating body 14.

In the prior art, a circular reference surface is formed on the spindle head, and a circular inner peripheral surface complementary to this reference surface is formed on the mounting plate of the detection portion of the rotation detector, and the circular inner surface of the mounting plate is formed. The mounting plate that holds the detection portion of the rotation detector is positioned by fitting the surface into the circular reference surface of the spindle head in an insole type.
Therefore, unless all the peripheral elements attached to the rotary shaft such as the main shaft have been removed, the mounting plate of the detection unit cannot be removed for replacement and repair of the detection unit. On the other hand, in the present embodiment, the spindle head 20 is provided with the reference surface 16b which is an outer peripheral surface concentric with the spindle 18, and the mounting plate 10
Is an arcuate plate member having an abutment surface 10e formed in a complementary shape to the reference surface 16b of the spindle head 20. Therefore,
The mounting plate 10 can be attached to and detached from the main shaft 18 in the vertical direction. Further, a bolt 2 which is a means for pressing and fixing the mounting plate
6, the washer 28, and the adjustment holes 10c and 10d of the mounting plate 10.
The mounting plate 10 is fixed to the mounting portion 16 of the spindle head 20 with the contact surface 10e of the mounting plate 10 pressed against the reference surface 16b of the spindle head 20, so that the mounting plate 10 can be accurately positioned. Is possible. As described above, it is possible to properly position the sensor 12 with respect to the rotating body 14 by previously adjusting the sensor 12 to the optimum position using a jig and attaching the sensor 12 to the mounting plate 10. Become.

In the above description, the reference surface 1 of the spindle head 20
Although 6b has a circular shape, the present invention is not limited to this.
Since the reference surface 16b is a means for accurately positioning the mounting plate 10, it is sufficient that the reference surface 16b and the contact surface 10e are precisely machined into complementary shapes. Therefore, the reference surface 16b may be an arcuate or elliptical outer peripheral surface, or may be a linear flat surface. The contact surface 10e of the mounting plate 10 is formed in a complementary shape according to the shape of these reference surfaces 16b. The point is that the mounting plate 10 only needs to have a shape that allows it to be attached to and detached from the main shaft 12 in a substantially vertical direction.

Although the mounting plate 10 has been described as an arc-shaped plate member in the above-described embodiments, the present invention is not limited to this. The contact surface 10e of the mounting plate 10 is used as the reference surface 1 of the spindle head 20.
Since the sensor 12 mounted on the mounting plate 10 is positioned by pressing against the mounting plate 1, the mounting plate 1
The shape of 0 may be any shape as long as the contact surface 10e is precisely processed to be complementary to the reference surface 16b.

Further, the sensor 12 as the detecting section is not limited to the magnetic sensor. The sensor 12 is determined by the type of the rotating body 14 that is the detected portion.
4 may be an optical sensor or an electrostatic capacitance sensor, for example.

Further, although the shape of the engaging portion 28b of the washer 28 is described by the Archimedes curve in the above-mentioned embodiment, this is merely an example and the shape is not limited to the Archimedes curve, and the engaging portion 28b is not limited to the Archimedes curve. It may be formed by another curve. In short, when the washer 28 is rotated, the contact surface 1 of the mounting plate 10
The shape may be such that 0e is pressed against the reference surface 16b of the spindle head 20. Engagement hole portion 10c of the adjustment hole of the mounting plate 10
Since the central axis O ₁ of the contact hole 10d is offset from the central axis O ₂ of the elongated hole 10d, even if the engaging portion 28b is formed in a hexagonal shape, by rotating the washer 28, the contact surface 10e becomes the reference surface. It is possible to press against 16b.

[0025]

According to the present invention, the detector can be attached / detached in the vertical direction with respect to the rotation axis without removing the surrounding mechanical elements. Further, the detection part can be accurately positioned with respect to the detected part by pressing and fixing the inner peripheral surface of the mounting plate to the reference surface of the support body by the mounting plate pressing and fixing means.

[Brief description of drawings]

FIG. 1 is a partial perspective view showing the periphery of an end portion of a spindle of a machine tool having a rotation detector.

FIG. 2 is a partial view showing a state in which the rotation detector mounting device according to the preferred embodiment of the present invention is mounted on the spindle head.
(A) is an end view seen in the direction of the central axis of the main shaft.
2B is a sectional view taken along the line II-II in FIG.

FIG. 3 is a schematic view of a mounting plate according to a preferred embodiment of the present invention. (A) is a top view. 3B is a sectional view taken along the line III-III in FIG.

FIG. 4 is a schematic view of a mounting portion for mounting the mounting plate on the spindle head. (A) is an end view seen in the direction of the central axis of the main shaft. 4B is a sectional view taken along the line IV-IV in FIG. 4A.

FIG. 5 is a schematic view of a washer according to a preferred embodiment of the present invention. (A) is a side view. (B) is a plan view.

FIG. 6 is a partial view showing a state in which a rotation detector mounting device according to a conventional technique is mounted on a spindle head. (A) is an end view seen in the direction of the central axis of the main shaft. 6B is a sectional view taken along the line VI-VI in FIG. 6A.

[Explanation of Codes] 10 ... Mounting plate 10c ... Engagement hole portion 10d ... Oblong hole 10e ... Contact surface 12 ... Sensor 14 ... Rotating body 16 ... Mounting portion 16b ... Reference surface 20 ... Spindle head 26 ... Bolt 28 ... Washer

Claims (1)

[Claims] 1. A detection unit of a rotation detector, comprising: a detection unit fixed to a rotating shaft rotatably supported by a support; and a detection unit for detecting an operation of the detection unit. In a rotation detector mounting and adjusting device for positioning and fixing to a body, a mounting plate having a reference surface formed on a support body, a contact surface formed in a complementary shape to the reference surface, and holding a detection part, and a mounting plate. A mounting device comprising: a mounting plate pressing contact fixing means for pressing the contact surface to the reference surface on the reference surface in a direction substantially perpendicular to the rotation axis.