JP2001004405A - Magnetic encoder device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable easy attaching work of a magnet for detecting a rotating position and a magnet for detecting a magnetic pole position with high precision. SOLUTION: A magnet 13 for detecting a rotating position and a magnet 14 for detecting a magnetic pole position are collectively attached to one rotating base member 12. The attaching work of both of the magnets 13, 14 are facilitated, the size and the weight of a rotating part are reduced, and the aligning work of magnetic pole positional relation between the magnets 13, 14 is performed without connection to a motor. Thereby both of the magnets 13, 14 are simply aligned with high precision, the rotating base member 12 provided with both of the magnets 13, 14 can be manufactured independently of the motor, and productivity is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a magnetic encoder device attached to a motor.

[0002]

2. Description of the Related Art Generally, in a magnetic encoder device attached to an AC servomotor or the like, as shown in FIGS. 8 and 9, a rotary shaft of a motor or a rotary shaft 1 integrally connected to the motor is used. A rotation position detection magnet (PG magnet) 2 for detecting rotation angle information, and a magnetic pole position detection magnet (pole magnet) 3 for detecting a current supply position to a motor driving coil are fixed. . A position detecting element 4 composed of an MR element or the like is disposed in close proximity to the rotational position detecting magnet 2 so that rotation angle information of several hundred to several thousand pulses per rotation can be obtained by the position detecting element 4. Are detected and output based on magnetic poles magnetized on the outer periphery of the rotational position detecting magnet 2. A magnetic pole position detecting element 5 composed of a Hall element or the like arranged opposite to the magnetic pole position detecting magnet 3 detects the energizing position of a motor driving coil (not shown) at several pulses per rotation. Output.

More specifically, a first rotating disk 6 made of aluminum or the like is fixed to the rotating shaft 1 by press-fitting or shrink-fitting. A magnetized rotation position detection magnet (PG magnet) 2 is attached. On the other hand, the magnetic pole position detecting magnet (pole magnet) 3 magnetized as shown in FIG. 8, for example, is fixed on the shaft end surface of a second rotating disk 7 made of an iron member or the like screwed to the rotating shaft 1. Have been.

[0004] When assembling the two magnets 2 and 3, first, the magnetic pole position detecting magnet 3 is fixed while the electrical angle with the motor driving coil or the driving magnet is adjusted. Next, while rotating the motor based on the signal detected from the magnetic pole position detecting magnet 3, the magnetic pole position detecting magnet 3 is attached to the rotating position detecting magnet 2 so as to have a predetermined magnetic pole positional relationship with the magnetic pole position detecting magnet 3. Magnetization is performed.

[0005]

However, in assembling the two magnets 2 and 3 in such a conventional device,
Since the rotational position detecting magnet 2 and the magnetic pole position detecting magnet 3 are separately fixed, at least two fixing operations are required, which is troublesome. Furthermore, due to a gap formed between the two members,
As the overall structure becomes larger, the moment of inertia of the rotating part increases. In addition, both magnets 2,
Since the magnets 3 are fixed at different places, the positional relationship between the two magnets 2 and 3 is likely to be shifted, and reliability may be a problem.

Accordingly, the present invention can easily and accurately mount a magnet for detecting a rotational position and a magnet for detecting a magnetic pole position, and can improve information detection performance and its reliability. It is an object to provide a magnetic encoder device as described above.

[0007]

In order to achieve the above object, according to the first aspect of the present invention, a rotating position detecting magnet for detecting rotation angle information is provided on a rotating shaft which rotates integrally with a motor. A magnetic pole position detecting magnet for detecting an energized position of a drive coil of the motor, and a magnetic encoder device in which the position is determined with respect to one rotating base fixed to the rotating shaft. The detection magnet and the magnetic pole position detection magnet are integrally mounted in a state where the magnetic pole positions are aligned with each other.

[0008] According to the second aspect of the present invention, in the first aspect,
The position detecting magnet described above is mounted on a peripheral surface of the rotating base, and the magnetic pole position detecting magnet is provided on an axial end surface of the rotating base.

According to a third aspect of the present invention, the magnetic pole position detecting magnet according to the first aspect and a position detecting element for detecting a signal from the position detecting magnet or the position detecting magnet. Magnetic shield means for blocking magnetic interference is provided.

Further, in the invention according to claim 4, the rotary base according to claim 3 is provided with an annular groove so as to be cut out in an axial direction from an axial end face of the rotary base. The magnetic shield means is arranged to enter the annular groove from the outside of the rotating base.

Further, in the invention according to claim 5, the magnetic shield means according to claim 3 is attached to the magnetic rotating base.

Further, in the invention according to claim 6, the magnetic shield means according to claim 3 is arranged near a magnetic pole position detecting element for detecting a signal from the magnetic pole position detecting magnet.

According to the invention having such a configuration, since the rotational position detecting magnet and the magnetic pole position detecting magnet are integrally mounted on one rotating base, the mounting operation is reduced. In addition, the size and weight of the entire apparatus can be reduced. In addition, since the positioning of the magnetic pole position relationship between the two magnets can be performed without being connected to a motor, the positional relationship between the two magnets is determined using a rotation position detecting magnet having a significantly higher resolution. These two magnets can be easily and accurately aligned. In addition, since the rotating base provided with these two magnets can be manufactured and managed completely independently of the motor, the productivity is improved.

By arranging the magnetic shield means as in the present invention, magnetic interference between the two magnets is prevented, and magnetic noise is reduced.
Good signal detection is performed.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings. First, in the embodiment shown in FIG. 1, a rotating shaft of an AC servomotor (not shown) or a rotating shaft 11 connected to the rotating shaft is formed of one non-magnetic material such as aluminum. The rotating base 12 is fitted. A fixing screw 12d is screwed in a radial direction to a boss 12a provided on the lower surface side of the rotating base 12 in the drawing, and the fixing screw 12d
The entirety of the rotating base 12 is fixed to the rotating shaft 11 by being tightened.

A rotating position detecting magnet (PG magnet) 1 is provided on the disk body 12b of the rotating base 12.
3, and a magnetic pole position detecting magnet (pole magnet) 14 are fixed. The position detecting magnet 13 is mounted so as to be annularly arranged with respect to the outer peripheral surface of the disk main body portion 12b of the rotating base 12, and is disposed radially from the outer peripheral surface of the position detecting magnet 13. A position detecting element 15 such as an MR element is disposed on the outer side so as to be closely opposed via a minute gap. The position detection element 15 detects rotation angle information obtained by multipolar magnetization of the position detection magnet 13 in the circumferential direction, and detects rotation angle information of hundreds to thousands of pulses per rotation. And output it.

Further, the magnet 14 for detecting the magnetic pole position
Is fixed to the axial end face of the disk main body 12b of the rotating base 12 on the upper side in the figure, and is magnetized, for example, in the same manner as indicated by the reference numeral 3 in FIG.
That is, a substantially circular concave step 12c is formed at the center of the upper end face in the figure of the disk main body 12b,
An annular magnetic pole position detecting magnet 14 is arranged so as to contact the outer peripheral wall surface of the concave step portion 12c.

On the other hand, a circuit board 16 is arranged in the upper region of the rotating base 12 in the figure so as to face the same at a predetermined interval. A plurality of magnetic pole position detecting elements 17 such as Hall elements are arranged on the circuit board 16 so as to be axially close to and opposed to the magnetic pole position detecting magnets 14. Detection element 17
From the point of view, the energizing position to the driving coil of the motor is detected at about several pulses per rotation.

At this time, the position detecting magnet 13
And the magnet 14 for detecting the magnetic pole position are mounted in a state where the magnetic pole positions are aligned with each other. Done in a separate place without connection. And both magnets 1
The rotating base 12 on which 3, 14 are integrally attached is
When the magnetic pole position detecting magnet 14 is mounted on the rotating shaft 11, the positional relationship with respect to the motor side of the magnet 14 is adjusted. In this case, the positioning operation of the magnetic pole positional relationship between the two magnets 13 and 14 can be easily and accurately performed by using the output signal from the rotation position detecting magnet 13 having a significantly high resolution as a reference. Will be

Further, an annular groove 18 is formed in the rotating base 12 in the outer peripheral area of the shaft end face on the upper side in the figure so as to be cut out from the shaft end face downward in the axial direction. The annular groove 18 is formed so as to extend concentrically over the entire circumference of the rotating base 12. On the other hand, a magnetic shield plate 19 is provided on the circuit board 16 at a position facing the annular groove 18 and opposed to the position detecting element 15 described above, and stands upright in the axial direction. The magnetic shield plate 19 is disposed so as to enter the annular groove 18 from above in the figure.

The magnetic shield plate 19 is made of a magnetic material for magnetic flux collection such as a magnetic steel plate or soft iron. The magnet 14 for detecting the magnetic pole position and the magnet 13 for detecting the position
The position detection element 15 and the position detection element 15 are arranged so as to be magnetically isolated, so that the influence of the strong magnetic field generated from the magnetic pole position detection magnet 14 is reduced by the position detection magnet 13 and the position detection element 15. The magnetic flux is collected so as not to exceed.

According to the present embodiment having such a configuration, the magnet 13 for detecting the rotational position and the magnet 14 for detecting the magnetic pole position are integrally attached to the single rotating base 12. Magnets 13, 14
Is simplified, and the size and weight of the entire rotating part can be reduced.

Further, since the positioning operation of the magnetic pole position relationship between the two magnets 13 and 14 can be performed without connecting to a motor, the position is determined using the rotational position detecting magnet 13 having a remarkably high resolution. A relationship can be obtained, whereby the two magnets 13 and 14 are easily and accurately aligned. Moreover,
The rotating base 12 provided with the two magnets 13 and 14 is
Since it can be manufactured and managed completely separately from the motor, productivity is improved.

Further, by disposing the magnetic shield plate 19 as in the present embodiment, the two magnets 1 are provided.
Magnetic interference between 3, 14 is prevented, magnetic noise is reduced, and good signal detection is performed.

In the second embodiment shown in FIG. 2 in which members corresponding to the above-described first embodiment are represented by the same reference numerals, first, a rotating base 12 is
Are fastened and fixed by a fixing screw 20 screwed in the axial direction. The magnetic shield plate 21 is not provided on the rotating base 12 side as in the first embodiment, but on the circuit board 1.
It is attached to the 6 side. The periphery of the magnetic pole position detecting element 17 except for the surface facing the magnetic pole position detecting magnet 14 is covered with the magnetic shield plate 21. Also in such an embodiment, it is possible to achieve the same operation and effect as in the first embodiment described above.

Next, in a third embodiment shown in FIG. 3 in which members corresponding to the above-described second embodiment are represented by the same reference numerals, a magnetic flux collecting element having a substantially L-shaped cross section will be described. A magnetic shield plate 22 made of a magnetic member is inserted at a joint between the rotating base 12 and the magnet 14 for detecting the magnetic pole position. In such an embodiment, the same operation and effect as those in the above-described embodiment can be obtained. In this case, if the entire rotating base 12 is formed of a magnetic material for magnetic flux collection, the rotating base 12 itself functions as a shield member, so that it is not necessary to use the separate shield plate 22 as described above. The configuration can be simplified.

Next, in a fourth embodiment shown in FIG. 4 in which members corresponding to the above-described third embodiment are represented by the same reference numerals, the magnetic shield plate 23 is formed in a ring shape. The ring-shaped magnetic shield plate 23 is provided between the outer peripheral portion of the magnetic pole position detecting magnet 14 and the circular step 12.
c is inserted at the joint with the inner peripheral wall surface. In such an embodiment, the same operation and effect as those in the above-described embodiment can be obtained.

Next, in each of the fifth, sixth, and seventh embodiments shown in FIGS. 5, 6, and 7 in which members corresponding to the above-described third embodiment are represented by the same reference numerals, The magnetic shield plate as in each embodiment described above is not used,
The magnetic pole position detecting magnet 14 is embedded in the upper end face of the rotating base 32 in the drawing, and in the embodiment shown in FIG. 6, the rotating base 32 is attached to the rotating shaft 11 without using a fixing screw. On the other hand, it is fixed by press fitting or shrink fitting. Further, in the embodiment shown in FIG. 7, the rotating base 32 is fastened and fixed by a fixing screw 33 screwed in the axial direction to the boss 32a. In each of such embodiments, it is possible to achieve the same operation and effect as in the above-described embodiment.

Although the embodiments of the present invention made by the inventor have been specifically described above, the present invention is not limited to the above-described embodiments, and can be variously modified without departing from the gist thereof. Needless to say.

[0030]

As described above, the present invention simplifies the mounting operation by integrally mounting the rotational position detecting magnet and the magnetic pole position detecting magnet on one rotating base. Small rotating parts
By reducing the weight and enabling the work of aligning the magnetic pole positions of the two magnets to be performed without connecting to a motor, the two magnets can be easily and accurately aligned with each other. The rotating body having both magnets can be manufactured separately from the motor, thereby improving productivity. The mounting work of the rotating position detecting magnet and the magnetic pole position detecting magnet can be performed easily and at high cost. Can be performed with precision,
Information detection performance and reliability can be improved at the same time.

In addition, according to the present invention, by arranging the magnetic shield means, the interference between the two magnets is prevented and the magnetic noise is reduced, so that the information detection performance and its reliability are further improved. Can be done.

[Brief description of the drawings]

FIG. 1 is an explanatory cross-sectional view showing a main part of a magnetic encoder device according to an embodiment of the present invention.

FIG. 2 is an explanatory cross-sectional view showing a main part of a magnetic encoder device according to another embodiment of the present invention.

FIG. 3 is a cross-sectional explanatory view showing a main part of a magnetic encoder device according to still another embodiment of the present invention.

FIG. 4 is a cross-sectional explanatory view showing a main part of a magnetic encoder device according to still another embodiment of the present invention.

FIG. 5 is an explanatory cross-sectional view showing a main part of a magnetic encoder device according to still another embodiment of the present invention.

FIG. 6 is a cross-sectional explanatory view showing a main part of a magnetic encoder device according to still another embodiment of the present invention.

FIG. 7 is an explanatory cross-sectional view showing a main part of a magnetic encoder device according to still another embodiment of the present invention.

FIG. 8 is an external perspective explanatory view showing a main part of a generally used magnetic encoder device.

FIG. 9 is an explanatory cross-sectional view showing a main part of the magnetic encoder device shown in FIG. 8;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Rotation axis 12 Rotation base 12b Disk body part 12c Circular concave step part 12d Fixing screw 13 Rotation position detection magnet (PG magnet) 14 Magnetic pole position detection magnet (pole magnet) 15 Position detection element (MR element) 16 Circuit board Reference Signs List 17 Magnetic pole position detecting element (Hall element) 18 Toroidal groove 19 Magnetic shield plate 20 Fixing screw 21, 22, 23 Magnetic shield plate 32 Rotating base 33 Fixing screw

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2F063 AA35 BB10 CA16 DA19 EA03 GA52 GA67 GA72 2F077 AA21 NN03 NN26 PP12 PP14 RR03 UU26 VV23

Claims (6)

[Claims] 1. A rotation position detecting magnet for detecting rotation angle information on a rotating shaft that rotates integrally with a motor, and a magnetic pole position detection for detecting a current supply position to a driving coil of the motor. In the magnetic encoder device in which the magnet and the magnet are fixed, the position detecting magnet and the magnetic pole position detecting magnet are aligned with respect to one rotating base fixed to the rotating shaft in a magnetic pole position relationship. A magnetic encoder device, wherein the magnetic encoder device is integrally mounted in a state where the magnetic encoder device is mounted. 2. The method according to claim 1, wherein the position detecting magnet is mounted on a peripheral surface of the rotating base, and the magnetic pole position detecting magnet is provided on an axial end surface of the rotating base. The magnetic encoder device according to claim 1, wherein: 3. A magnetic shield means for blocking magnetic interference is arranged between the magnetic pole position detecting magnet and the position detecting magnet or a position detecting element for detecting a signal from the position detecting magnet. 2. The magnetic encoder device according to claim 1, wherein: 4. An annular groove is recessed in the rotating base so as to be cut out in an axial direction from an axial end face of the rotating base, and the magnetic shield means is provided in the rotating base from an outer side of the rotating base. The magnetic encoder device according to claim 3, wherein the magnetic encoder device is disposed so as to enter the annular groove. 5. The magnetic encoder device according to claim 3, wherein said magnetic shield means is attached to said magnetic rotating base side. 6. The magnetic encoder device according to claim 3, wherein said magnetic shield means is disposed near a magnetic pole position detecting element for detecting a signal from said magnetic pole position detecting magnet.