JP2000298039A - Position control mechanism of magnetic sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To finely control the attaching position of magnetic sensor and facilitate the control of detection accuracy of the magnetic sensor. SOLUTION: The case 2 of a magnetic sensor 1 is guided to the arrows A1 direction and A2 direction against a stay 29. Between the case 2 and the stay 29, an energizing member 35 for energizing the magnetic sensor 1 in the direction parting from a rotor 28 and a position control screw 37 are provided. By rotating the position control screw 37 and spirally proceeding back and forth, the attaching position of the magnetic sensor 1 to the stay 29 and the gap 39 between the circumference of the rotor 28 and the detection surface 8a of the magnetic sensor 1 can be controlled. After the position control, the case 2 is finally fixed with a screw to the stay 29.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a magnetic sensor position adjusting mechanism for adjusting a mounting position of a magnetic sensor.

[0002]

Conventionally, there has been a magnetic rotary encoder for detecting, for example, the number of revolutions of a motor using magnetism. This has a configuration including a rotating body made of a magnetic material having a gear shape and a magnetic sensor having a magnetic detecting element. Of these, the rotating body is
It is attached to the rotating shaft of the motor so as to rotate integrally therewith. Then, the magnetic sensor is mounted and fixed to the mounting portion such that its detection surface faces the outer peripheral portion of the rotating body.

In this case, it is necessary to adjust a mounting position of the magnetic sensor in order to adjust a gap between a detection surface of the magnetic sensor and an outer peripheral portion of the rotating body. For this reason, conventionally, a long hole is formed in one of the magnetic sensor and the mounting portion, and by using the long hole and the mounting screw inserted through the long hole,
The magnetic sensor is mounted and fixed to the mounting portion while adjusting the gap.

However, in the above-described conventional configuration, there is a problem that although the position of the magnetic sensor can be roughly adjusted, it is difficult to finely adjust the position, and it is difficult to adjust the detection accuracy of the magnetic sensor.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to make it possible to finely adjust a mounting position of a magnetic sensor and to easily adjust the detection accuracy of the magnetic sensor. An object of the present invention is to provide a position adjustment mechanism of a magnetic sensor.

[0006]

In order to achieve the above-mentioned object, a first aspect of the present invention is a position adjusting mechanism for adjusting a mounting position of a magnetic sensor, which reciprocates the magnetic sensor in an adjusting direction. A stay which is provided so as to be guided as possible, and which is attached and fixed to an attachment portion, and an urging member which is provided between the stay and the magnetic sensor so as to urge the magnetic sensor in one direction of the adjustment direction. A member and a position adjusting screw that is provided between the stay and the magnetic sensor so as to be able to advance and retreat, and moves the magnetic sensor in the adjustment direction in accordance with the advance and retraction.

According to the above-described means, the mounting position of the magnetic sensor can be finely adjusted by rotating the position adjusting screw to advance and retreat.

In this case, the urging member and the position adjusting screw are
It is preferable to dispose the position adjusting screws so as to be spaced apart in the axial direction (the invention of claim 2). According to this, it is possible to prevent the occurrence of biting between the position adjusting screw and the urging member when the position adjusting screw is turned.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment in which the present invention is applied to a magnetic rotary encoder will be described below with reference to FIGS. The case 2 of the magnetic sensor 1 has a receiving portion 3 formed therein, a rectangular opening 4 formed in a portion serving as a front detection surface, and an insertion opening larger than the opening 4 also in the rear portion. 5 are formed. Storage section 3
And the opening 4 and the insertion opening 5 communicate with each other. A rectangular frame 6 protrudes from the periphery of the opening 4, and mounting holes 7 are formed at four locations around the frame 6.

On the front surface of the case 2, a plate 8 in the form of a shallow container is arranged so as to cover the opening 4 and the frame 6 from the front. In the plate 8, a portion corresponding to the opening 4 is a detection surface 8a. The plate 8 is formed of a thin plate having a thickness of about 0.1 mm. Four screw insertion holes 9 are formed in the flange portion 8 b at the peripheral edge of the plate 8 in correspondence with the mounting holes 7. A paste sealing material 10 (FIG. 4)
This sealing material 10 is applied to the frame 6
And the inner surface of the plate 8.

On the front side of the plate 8, the plate 8
A rectangular frame-shaped frame 11 is arranged so as to press the flange portion 8b, which is the peripheral portion of the frame, from the front surface. Is formed. So, frame 1
Each screw 13 sequentially inserted through the screw insertion hole 12 of the first plate 1 and the screw insertion hole 9 of the plate 8 is
The plate 8 into the case 2
It is fixed to the front of In this case, the case 2, the plate 8 and the frame 11 are each formed of aluminum which is a non-magnetic material.

As shown in FIGS. 1 and 2, a sensor unit 14 is housed in the housing 3 of the case 2. The holder 15 of the sensor unit 14 has first and second front and rear magnetoresistive elements (MRE).
A sensor IC 18 having magnetic detection elements 16 and 17 is provided, and a bias magnet 1 serving as a magnetic generating means is positioned at the rear side of the sensor IC 18.
9 and two circuit boards 20a and 20b. The first and second magnetic detecting elements 16 and 17 are arranged vertically when viewed from the front. Among them, the first magnetic detecting element 16 is for detecting a reference position signal, and the second magnetic detecting element 1
Reference numeral 7 is for detecting a rotation signal. Two circuit boards 20
Of the circuits a and 20b, the circuit board 20b positioned above is provided with a plurality of output adjusting volumes 21.

The sensor unit 14 is inserted into the storage section 3 through the rear insertion opening 5 and the holder 15 is fixed in the storage section 3 by tightening the screw 22 from the insertion opening 5 side. It is arranged. In this arrangement state, the first and second magnetic detecting elements 16 and 17 are in close contact with the inner surface of the detecting surface 8a. In case 2,
An opening is formed in a portion corresponding to the volume 21, and a cover 24 for closing the opening is provided with a screw 25.
It is attached by. A rear cover 26 is also attached to the rear of the case 2 with screws 27 so as to close the insertion opening 5.

The magnetic sensor 1 constructed as described above is arranged near a rotating body 28 to be detected, which will be described later, and has a predetermined mounting portion 30 via a stay 29 arranged on the lower surface side.
(See the two-dot chain line in FIG. 1). Next, the mounting structure of the magnetic sensor 1 will be described mainly with reference to FIGS.

First, a relatively large elliptical opening 3 is formed on the left and right sides of the lower part of the case 2 of the magnetic sensor 1.
1 and the stay 29 has an opening 31
It is configured to be fixed to the mounting portion 30 by a screw 32 (see a two-dot chain line in FIG. 2) that passes therethrough. The opening 31
Is formed in a shape sufficiently larger than the head of the screw 32.

The case 2 of the magnetic sensor 1 includes a stay 29
In the front-rear direction (FIG. 1 and FIG.
(See arrows A1 and A2). An urging member 35 made of a compression coil spring is provided between a spring receiving portion 33 provided on the lower surface of the case 2 and a spring receiving portion 34 provided on a front portion of the stay 29.
Is provided, and the magnetic sensor 1 is provided with the biasing member 35.
Urged in the direction away from the rotating body 28 (the direction of the arrow A1).

A position adjusting screw 37 inserted into a screw insertion hole 36a of a projecting portion 36 provided at a rear portion of the case 2 is provided.
Is screwed into a screw hole 38 provided at the rear of the stay 29 from behind, and by rotating this position adjusting screw 37 to advance and retreat, the position of the magnetic sensor 1 with respect to the stay 29, and thus the rotating body 28 The gap 39 between the outer peripheral portion of the magnetic sensor 1 and the detection surface 8a of the magnetic sensor 1 can be adjusted. In this case, the urging member 35 and the position adjustment screw 37 are arranged in the axial direction of the position adjustment screw 37, but are arranged apart from each other. Here, stay 29
, The urging member 35 and the position adjusting screw 37 constitute a position adjusting mechanism 40 of the magnetic sensor 1.

The magnetic sensor 1 is attached to the stay 29 by tightening the screws 42 inserted into the screw insertion holes 41 (see FIG. 4) formed on the right and left sides of the lower front part of the case 2. Fixed.

On the other hand, the rotating body 28 is made of a magnetic material, and has a reference position signal generating section 43 having only one mountain-shaped projection 43a on the outer periphery, and a plurality of mountain-shaped projections 44 on the outer periphery.
A rotation signal generating section 44 having a at equal intervals is provided above and below, and is attached to, for example, a rotating shaft of a motor (not shown) so as to rotate integrally therewith. In this case, a notch 45 for forming a gap between the reference position signal generator 43 and the rotation signal generator 44 is formed below the protrusion 43a.
(See FIG. 1). In the magnetic sensor 1, the first magnetic detecting element 16 includes a reference position signal generating section 43, and the second magnetic detecting element 17 includes a rotation signal generating section 44.
And are arranged so as to face each other from the outer peripheral portion via the detection surface 8a.

In the above configuration, when the rotating body 28 rotates, the magnetic flux linked to the first and second magnetic detecting elements 16 and 17 changes, and accordingly, the first and second magnetic detecting elements 16 and 17 change. Since the output signal output from the output signal 17 changes, by detecting the change in the output signal, the rotation speed of the rotating body 28, and thus the motor, can be detected.

According to the above-described embodiment, the position adjustment mechanism 40 is provided below the magnetic sensor 1, and the position adjustment screw 37 of the position adjustment mechanism 40 is rotated to advance and retreat, so that the magnetic sensor 1 The position of attachment to the rotating body 28, and thus the gap 39 between the outer peripheral portion of the rotating body 28 and the detection surface 8a of the magnetic sensor 1, can be finely adjusted, so that the detection accuracy of the magnetic sensor 1 can be easily adjusted.

Further, the urging member 35 and the position adjusting screw 37 in the position adjusting mechanism 40 are
When the position adjustment screw 37 is turned, the position adjustment screw 37 and the urging member 3
There is an advantage that it is possible to prevent the occurrence of biting between the first and the second embodiment.

FIG. 5 shows a second embodiment of the present invention. The second embodiment differs from the first embodiment in the following points. That is, in the position adjusting mechanism 46, between the projecting portion 36 of the case 2 of the magnetic sensor 1 and the stay 47, an urging member 48 made of a compression coil spring is provided.
And the position adjusting screw 49 is set to be longer than the position adjusting screw 37. With the position adjusting screw 49 inserted through the urging member 48, the screw hole 50 of the stay 47 is inserted.
From behind.

Also in this case, the rotating body 28 of the magnetic sensor 1 is rotated and retracted by rotating the position adjusting screw 49.
And the gap 39 between the outer peripheral portion of the rotating body 28 and the detection surface 8a of the magnetic sensor 1 can be finely adjusted.

[0025]

According to the position adjusting mechanism of the magnetic sensor of the present invention, the position of the magnetic sensor can be finely adjusted by rotating the position adjusting screw to advance and retreat.
Consequently, the detection accuracy of the magnetic sensor can be easily adjusted.

According to the position adjusting mechanism of the magnetic sensor according to the second aspect, it is possible to prevent the occurrence of biting between the position adjusting screw and the urging member when the position adjusting screw is turned.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view showing a first embodiment of the present invention.

FIG. 2 is a cross-sectional plan view

FIG. 3 is a front view of a magnetic sensor.

FIG. 4 is an exploded perspective view of a case portion of the magnetic sensor.

FIG. 5 is a view corresponding to FIG. 1 showing a second embodiment of the present invention.

[Explanation of symbols]

1 is a magnetic sensor, 2 is a case, 16 and 17 are first and second
, A rotating body, 29 is a stay, 30 is a mounting part, 35 is a biasing member, 37 is a position adjusting screw, 40 is a position adjusting mechanism, 43 is a reference signal generating part, and 44 is a rotation signal generating part. , 46 indicate a position adjusting mechanism, 47 indicates a stay, 48 indicates an urging member, and 49 indicates a position adjusting screw.

Claims (2)

[Claims] 1. A stay for adjusting a mounting position of a magnetic sensor, the stay being provided so as to reciprocally move the magnetic sensor in an adjusting direction, and being mounted and fixed to a mounting portion. And an urging member provided between the magnetic sensor and the magnetic sensor so as to urge the magnetic sensor in one direction of the adjustment direction. A position adjusting screw for moving the magnetic sensor in the adjustment direction as the screw advances and retreats. 2. The position adjusting mechanism for a magnetic sensor according to claim 1, wherein the urging member and the position adjusting screw are arranged apart from each other in the axial direction of the position adjusting screw.