JP3223500B2 - Stepping motor type instrument - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stepping motor type instrument using a stepping motor capable of rotating forward and backward as a movable portion of an indicating instrument.

[0002]

2. Description of the Related Art PM-type stepping motors have been widely used as actuator parts in the fields of OA equipment, home electric appliances, automobiles and the like (for example, JP-A-5-161333, JP-A-3-145960). Japanese Patent Laid-Open Publication No. Hei 1-190249 and Japanese Patent Laid-Open Publication No. Hei 1-190248), the forward and reverse rotation control is easy, and the size can be easily reduced depending on the driving torque. Has also attracted attention.

When such a stepping motor is used as an indicating instrument, for example, as shown in FIG. 6, annular bobbins C and D around which exciting coils A and B are wound and exciting coils A and B are used.
Are concentrically laminated with each other to form a stator H having a hollow portion G, and the exciting coil A guided to the hollow portion G of the stator H through the annular yokes E and F. , B, and accommodates a rotor J composed of a permanent magnet having a rotation axis I which is driven to rotate by the magnetic path of the support plate K or L fixed to the stator H with respect to the rotation axis I of the rotor J. Bearing member K composed of oil-impregnated bearings
1, a connecting base M1 of a pointer M is press-fitted and fixed to the tip of a rotating shaft I protruding from a support plate K, and an instrument dial N is arranged between the pointer M and the support plate K. If the signal (current) supplied to the excitation coils A and B is controlled in accordance with the measured amount (for example, the running speed of the vehicle or the engine speed), the measured amount on the instrument dial N by the indicator M2 of the pointer M can be obtained. Instructions are possible.

[0004]

However, in such a structure in which the pointer M is simply mounted on the tip of the rotary shaft I, the bearing member K1 protrudes from the support plate K toward the pointer M, and the rotation of the pointer M takes place. It is necessary to extend the connecting base M1 to the rotor J side in order to secure a contact area between the shaft I and the connecting base M1 of the pointer M and to stably fix the pointer M to the rotating shaft I. There is a problem that the portion of the rotation axis I protruding from the support plate K toward the pointer M becomes longer, and the height O from the motor bottom surface to the front surface of the pointer M becomes larger.

SUMMARY OF THE INVENTION The present invention has been made in view of the above, and an object of the present invention is to provide a stepping motor type instrument which can reduce the height dimension by devising a motor structure and achieve a thinner device.

[0006]

In order to achieve the above object, the present invention provides a hollow portion formed by laminating an annular bobbin on which an exciting coil is wound and an annular yoke for guiding a magnetic path of the exciting coil. And a rotor comprising a permanent magnet rotatably housed in the hollow portion and rotatable by a magnetic path of the exciting coil guided through the annular yoke, and connected to one end of the rotating shaft. A pointer that has a connecting base and an indicator that extends in a direction substantially perpendicular to the rotation axis and that responds to the rotor; and a bearing member that is fixed between the pointer and the stator and that supports the rotation axis of the rotor. A stepping motor type instrument comprising a metal supporting plate provided, and instructing the measurement amount by the pointer by supplying a signal corresponding to the measurement amount to the excitation coil, A first recess is formed at the support plate position corresponding to the connection base of the needle and projects toward the rotor to receive and hold the bearing member. The first recess is provided at the rotor position corresponding to the first recess. Is provided with a second recess for accommodating the same.

According to the present invention, the first concave portion accommodates a connecting base of the pointer.

Further, the present invention provides a stator having a hollow portion formed by laminating an annular bobbin around which an exciting coil is wound and an annular yoke for guiding a magnetic path of the exciting coil, and rotatably housed in the hollow portion. A rotor composed of a permanent magnet having a rotating shaft rotated by a magnetic path of the exciting coil guided through the annular yoke, a connecting base connected to one end of the rotating shaft, and a direction substantially orthogonal to the rotating shaft. A pointer that has an indicating portion that extends to the rotor and that is responsive to the rotor; and a resin support plate that is fixed between the pointer and the stator and that supports the rotating shaft of the rotor. A stepping motor-type instrument for instructing the measurement amount by the pointer by supplying a signal corresponding to the pointer, wherein the needle is positioned at the position of the support plate corresponding to the connection base of the pointer. The rotating shaft to form a first recess for accommodating the connecting base and holds a bearing to protrude on the other side,
A second recess for accommodating the first recess is formed at the rotor position corresponding to the first recess.

[0009]

According to the present invention, a stator having a hollow portion is provided by laminating an annular bobbin wound with an exciting coil and each annular yoke for guiding a magnetic path of the exciting coil. A rotor having a rotating shaft rotated by a magnetic path of an exciting coil guided through an annular yoke is rotatably housed in the portion, and a metal supporting plate having a bearing member for supporting the rotating shaft of the rotor is provided on the stator. A stepping motor body is provided, and a pointer having a connecting base and an indication portion which is press-fitted and fixed to the rotating shaft is provided at a tip of a rotating shaft of the stepping motor body, and a signal corresponding to a measured amount is supplied to the exciting coil. By doing so, a stepping motor-type instrument that indicates the measurement amount by the indicator of the pointer on the instrument dial is configured, and the row is moved to the indicator plate position corresponding to the connection base of the pointer. By forming a first recess for projecting to the side and receiving and holding the bearing member, and providing a second recess for housing the first recess at a rotor position recessed against the first recess, The protruding portion from the support plate is absorbed by the first and second concave portions, and the rotating shaft portion protruding from the support plate to the pointer side is shortened, thereby reducing the height dimension.

At this time, if the connecting base of the pointer is also accommodated in the first recess, the rotating shaft portion protruding from the support plate toward the pointer can be further shortened, and the height dimension can be suppressed.

According to the present invention, a stator having a hollow portion is provided by laminating an annular bobbin wound with an exciting coil and respective annular yokes for guiding a magnetic path of the exciting coil. A rotor having a rotating shaft rotated by a magnetic path of an exciting coil guided through a yoke is rotatably housed, and a resin supporting plate for supporting a rotating shaft of the rotor is provided on a stator to constitute a stepping motor body, At the tip of the rotating shaft of this stepping motor main body, a pointer having a connecting base press-fitted and fixed to the rotating shaft and an indicating portion is provided, and a signal corresponding to the measured amount is supplied to the exciting coil, so that it is displayed on the instrument dial. The stepper motor type instrument which indicates the measurement amount by the indicator of the pointer is constructed, and it is projected to the rotor side at the indicator plate position corresponding to the connection base of the pointer, and the rotating shaft A first recess for holding the bearing and accommodating the coupling base is formed, and a second recess for accommodating the first recess is provided at a rotor position recessed with respect to the first recess, thereby extending toward the rotor. The clearance of the connecting base of the pointer is formed in the stator, the rotating shaft portion protruding from the support plate toward the pointer is shortened, and the height is reduced.

[0012]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

1 to 3 show a stepping motor type instrument according to a first embodiment of the present invention. FIG. 1 is an exploded perspective view of the stepping motor type instrument, and FIG. 2 is a stepping motor shown in FIG. FIG. 3 is an exploded perspective view of the main body, and FIG. 3 is a sectional view showing an assembled state of the stepping motor type instrument shown in FIG.

In FIG. 1, a stepping motor type instrument according to the present embodiment comprises a stepping motor main body 1 having a rotating shaft projecting forward, which will be described later, and a light guide plate 2 disposed in front of the stepping motor main body 1. The instrument dial 3 includes an instrument dial 3 arranged in front of the light guide plate 2 and a pointer 4 mounted on the rotary shaft of the stepping motor main body 1 located on the instrument dial 3.

As shown in FIG. 2, the stepping motor main body 1 has a first exciting coil 13 wound around an annular yoke 12 composed of a cup-shaped outer yoke 10 and a flat inner yoke 11. Stator 15 having a first annular bobbin 14 made of resin sandwiched in a stacked state, and a cup-shaped outer yoke 16
A second annular bobbin 20 made of a resin around which a second excitation coil 19 is wound is sandwiched between an annular yoke 18 composed of a plate-shaped inner yoke 17 and a second yoke 18. Stator 21
Each of the annular yokes 12 and 18 is formed by stamping and pressing a flat metal plate made of an iron-based material such as SEC, SPC, or Permalloy.
A plurality of pole teeth 10 extending from 0, 11, 16 and 17 into the winding portions of the annular bobbins 14 and 20 and being combined with each other in a comb shape.
a, 11a, 16a, and 17a are formed.

The stators 15 and 21 are laminated concentrically so that the opening sides of the outer yokes 10 and 16 constituting the stators face each other, and constitute a laminate having a hollow portion 22 (see FIG. 3) at the center. Then, the rotor 23 is rotatably housed and disposed in the hollow portion 22 of the laminate.

The rotor 23 is formed of a cylindrical permanent magnet having a plurality of magnetic poles on its peripheral surface corresponding to the pole teeth 10a, 11a, 16a, and 17a of the annular yokes 12 and 18, and the center of its center. A rotating shaft 24 whose both ends are supported by support plates 25 and 26 is fixed, and is formed by supplying a signal to be described later to each of the exciting coils 13 and 19, and is rotated forward and backward by a magnetic path guided through each of the annular yokes 12 and 18. It rotates in the direction.

The support plates 25, 26 are provided with the respective stators 15, 21.
Consists of a metal plate fixed to the outer surfaces of the outer yokes 10 and 16,
Bearing members 27 and 28 made of resin or oil-impregnated bearings are fixed at positions corresponding to the rotating shaft 24, respectively.

Of the support plates 25 and 26, the pointer 4
At the position of the support plate 25 facing a connecting base described later, a first concave portion 29 protruding toward the rotor 23 in FIG. 3 showing the assembled state is formed.
The bearing member 27 is fixed and held in the housed state on the bottom portion 30 on the projecting side. On the other hand, on the front side of the rotor 23 corresponding to the first recess 29, a second recess 23 which is larger than the outer diameter of the first recess 29 and accommodates the first recess 29 including the bearing member 27 therein.
a is formed.

The support plate 25 has a mounting portion 31 for mounting the stepping motor main body 1 on the light guide plate 2. The support plate 25 is used for mounting the stepping motor main body 1 on another member. It also has the function of a member.

As shown in FIG. 3, the stepping motor main body 1 constructed as described above is provided with a mounting portion for the support plate 25.
A pointer 4 is attached to and fixed to the light guide plate 2 supporting the instrument dial 3 through screws 31 through a through hole 33 formed in the light guide plate 2 and the instrument dial 3. Be linked.

In this case, the light guide plate 2 is made of a translucent resin such as acryl or polycarbonate.
Is formed of a so-called transmissive dial plate on which a translucent display portion (not shown) for characters, numerals, indicators, etc. is formed except for a ground color portion.
, And a light from a light source (not shown) is guided through the light guide plate 2 behind the instrument dial 3 and the hands 4 so that the light transmitted through the instrument dial 3 is transmitted. Translucent resin substrate for the light-sensitive display part and the pointer 4
35 is made to shine.

The light-transmitting resin substrate 35 constituting the pointer 4
Is a cylindrical connecting base 36 that extends in the axial direction of the rotating shaft 24 and is press-fitted and fixed to the rotating shaft 24, and an indicator that extends from the front of the connecting base 36 in a direction substantially orthogonal to the axial direction of the rotating shaft 24. At the position of the support plate 25 facing the connecting base 36 as described above, the first recess 29 larger than the outer diameter of the connecting base 36 is formed.

The stepping motor type instrument configured as described above controls the signal (current) supplied to the exciting coils 13 and 18 in accordance with the measured amount (for example, the running speed of the vehicle or the engine speed), thereby providing a pointer. 4 rotates on the instrument dial 3 in response to the rotor 23, and performs the measurement amount instruction by reading the contrast of the indicator 37 of the pointer 4 and the translucent display of the instrument dial 3. I have.

As described in detail above, the stepping motor type instrument according to the present embodiment guides the annular bobbins 14, 20 around which the exciting coils 13, 19 are wound and the magnetic paths of the exciting coils 13, 19, respectively. The first and second stators 15 and 21 each having a hollow portion 22 are provided by laminating the respective annular yokes 12 and 18.
A rotor 23 having a rotating shaft 24 rotated by a magnetic path of each of the exciting coils 13 and 19 guided through each of the annular yokes 12 and 18 is rotatably housed in the hollow portion 22 of each of the stators 15 and 21. The stepping motor body 1 is provided with support plates 25 and 26 having bearing members 27 and 28 for supporting the rotating shaft 24 of the rotor 23.
And a pointer 4 having a connecting base 36 and a pointing portion 37, which is press-fitted and fixed to the rotating shaft 24, is provided at the tip of the rotating shaft 24 of the stepping motor main body 1.
And a signal corresponding to the measured amount is supplied to the instrument dial 3 so that a stepping motor type instrument for indicating the measured amount by the indicating portion 37 of the hands 4 on the instrument dial 3 is constituted.
A first concave portion 29 is formed at a position of the support plate 25 corresponding to 36 to protrude toward the rotor 23 and accommodates and holds the bearing member 27. A first concave portion 29 is formed at a position of the rotor 23 corresponding to the first concave portion 29.
Is provided, the protrusion of the bearing member 27 from the support plate 25 is absorbed by the stator 15, that is, the first and second recesses 29 and 23a. The portion of the rotating shaft 24 protruding toward the hands 4 is shortened, and the height S from the bottom surface of the stepping motor main body 1 to the front surface of the hands 4 can be suppressed to achieve a reduction in thickness. The lower support plate 26, to which the bearing member 28 is fixed, is also provided with a recess similar to the first recess 29 of the support plate 25. The second under the rotor 23
If the concave portion similar to the concave portion 23a is formed, the bearing member 28 does not protrude from the bottom surface of the support plate 26, and the thickness including the rotating shaft 24 can be reduced.

FIG. 4 is a sectional view showing a main part of a second embodiment of the present invention. In this embodiment, a part of a connecting base 36 of a pointer 4 is formed on a support plate 25 together with a bearing member 27. Recess
29, and the other parts are
This is the same as the embodiment.

With this configuration, the same effect as that of the first embodiment can be obtained, and the clearance of the connecting base 36 of the pointer 4 can be formed in the stator 15 so as to protrude from the support plate 25 toward the pointer 4. The height dimension can be suppressed by further shortening the rotating shaft 24 portion.

FIG. 5 is a cross-sectional view showing a third embodiment of the present invention. In this embodiment, support plates 25 and 26 are formed of synthetic resin, and a through-hole-shaped bearing portion 38 for holding the rotating shaft 24 as a bearing is provided. ,
39, thrust regulating portions 40 and 41 of the rotor 23 are provided around the bearing portions 38 and 39, and the rotor 23 made of a permanent magnet is rotated through the magnet holder 23b.
At the position of the support plate 25 opposite to the connecting base 36 of the pointer 4, a first recess 29 for accommodating the connecting base 36 of the pointer 4 is formed, and the bottom 30 of the first recess 29 is formed. The bearing portion 38 and the thrust regulating portion 40 are provided on the
At a position of the rotor 23 facing the rotor 29, a second recess 23a for accommodating the first recess 29 is formed.

An instrument dial 3 is disposed in front of the stepping motor main body 1 thus configured. The instrument dial 3 and the stepping motor main body 1 are screwed through a mounting portion 31 of the support plate 25. The other parts are the same as in the first embodiment.

With this configuration, the clearance of the connecting base 36 of the pointer 4 extending toward the rotor 23 can be formed in the stator 15, and the portion of the rotating shaft 24 protruding from the support plate 25 toward the pointer 4 can be shortened. Further, the height S from the bottom surface of the stepping motor main body 1 to the front surface of the pointer 4 can be suppressed to achieve a reduction in thickness. In this example, the rotating shaft
Although the lower end of 24 is provided to protrude from the support plate 26,
If the lower end of the rotating shaft 24 is provided so as not to protrude from the support plate 26, the thickness including the rotating shaft 24 can be reduced.

In this embodiment, the bearing portion 38 is formed in a simple through hole shape. However, the bearing portion 38 is formed in a cylindrical shape projecting toward the hands 4 or the rotor 23, and a portion projecting toward the hands 4 is formed in the first recess 29.
You may make it accommodate in.

[0032]

As described in detail above, the present invention relates to a stator having a hollow portion formed by laminating an annular bobbin around which an exciting coil is wound and an annular yoke for guiding a magnetic path of the exciting coil. A rotor comprising a permanent magnet rotatably housed in a hollow portion and having a rotating shaft rotated by a magnetic path of the exciting coil guided through the annular yoke; a connecting base connected to one end of the rotating shaft; A pointer having a pointing portion extending in a direction substantially perpendicular to the shaft, the pointer being responsive to the rotor, and a bearing member fixed between the pointer and the stator and supporting a rotating shaft of the rotor. A stepping motor type instrument comprising a support plate and supplying the signal corresponding to the measured amount to the exciting coil to instruct the measured amount by the pointer, corresponding to a connection base of the pointer. A first recess for projecting toward the rotor and receiving and holding the bearing member is formed at the support plate position, and a second recess for housing the first recess at the rotor position corresponding to the first recess. Providing the concave portion can provide a stepping motor that can achieve a reduction in thickness.

Further, according to the present invention, further reduction in thickness can be achieved by the first recess accommodating the connecting base of the pointer.

The present invention also provides a stator having a hollow portion formed by laminating an annular bobbin around which an exciting coil is wound and an annular yoke for guiding a magnetic path of the exciting coil, and rotatably housed in the hollow portion. A rotor composed of a permanent magnet having a rotating shaft rotated by a magnetic path of the exciting coil guided through the annular yoke, a connecting base connected to one end of the rotating shaft, and a direction substantially orthogonal to the rotating shaft. A pointer which has an indicating portion extending to the rotor and which is responsive to the rotor; and a resin support plate which is fixed between the pointer and the stator and supports a rotating shaft of the rotor. A stepping motor-type instrument for instructing the measurement amount by the pointer by supplying a signal corresponding to the pointer, wherein the needle is positioned at the position of the support plate corresponding to the connection base of the pointer. The rotating shaft to form a first recess for accommodating the connecting base and holds a bearing to protrude on the other side,
By forming the second recess for accommodating the first recess at the rotor position corresponding to the first recess, it is possible to provide a stepping motor capable of achieving a reduction in thickness.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a stepping motor type instrument according to a first embodiment of the present invention.

FIG. 2 is an exploded perspective view of the stepping motor main body shown in FIG.

FIG. 3 is a sectional view showing an assembled state of the stepping motor type instrument main body shown in FIG. 1;

FIG. 4 is a sectional view of a main part of a stepping motor type instrument according to a second embodiment of the present invention.

FIG. 5 is a sectional view of a stepping motor according to a third embodiment of the present invention.

FIG. 6 is a sectional view showing a conventional example.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 stepping motor main body 2 light guide plate 3 instrument dial plate 4 hands 10, 16 outer yokes 10 a, 11 a, 16 a, 17 a 11, 17 inner yokes 12, 18 first and second annular yokes 13, 19 first and second Excitation coil 14, 20 First and second annular bobbins 15, 21 First and second stator 22 Hollow part 23 Rotor 23a Second concave part 23b Magnet holder 24 Rotating shaft 25, 26 Support plate 27, 28 Bearing member 29 First concave portion 30 Bottom portion 31 Mounting portion 32 Screw 33 Through hole 34 Light-shielding cover 35 Translucent resin base 36 Connecting base 37 Indicator 38, 39 Bearing 40, 41 Thrust restrictor S Height

Claims (3)

(57) [Claims] A stator provided with a hollow portion formed by laminating an annular bobbin around which an exciting coil is wound and an annular yoke for guiding a magnetic path of the exciting coil; and the annular portion rotatably housed in the hollow portion. A rotor consisting of a permanent magnet having a rotating shaft rotated by a magnetic path of the exciting coil guided through a yoke, a connecting base connected to one end of the rotating shaft, and an instruction extending in a direction substantially orthogonal to the rotating shaft; And a metallic support plate having a bearing member fixed between the pointer and the stator and supporting a rotating shaft of the rotor. A stepping motor type instrument for instructing the measurement amount by the pointer by supplying a signal corresponding to the measurement amount, wherein the position of the support plate corresponding to the connection base of the pointer is A second recess is formed to protrude toward the rotor side to receive and hold the bearing member, and to accommodate the first recess at the rotor position corresponding to the first recess.
A stepping motor type instrument provided with a concave portion. 2. A stepping motor type instrument according to claim 1, wherein said first recess houses a connecting base of said pointer. 3. A stator having a hollow portion formed by laminating an annular bobbin around which an exciting coil is wound and an annular yoke for guiding a magnetic path of the exciting coil, and the annular portion rotatably housed in the hollow portion. A rotor consisting of a permanent magnet having a rotating shaft rotated by a magnetic path of the exciting coil guided through a yoke, a connecting base connected to one end of the rotating shaft, and an instruction extending in a direction substantially orthogonal to the rotating shaft; And a pointer responsive to the rotor having a portion, and a resin support plate fixed between the pointer and the stator and supporting a rotating shaft of the rotor, the excitation coil corresponding to a measured amount. A stepping motor type instrument for supplying the signal to indicate the measurement amount by the pointer, wherein the stepper motor-type instrument projects to the rotor side at the support plate position corresponding to the connection base of the pointer. Forming a first recess for accommodating the coupling base and holding the rotary shaft as a bearing, and forming a second recess for accommodating the first recess at the rotor position corresponding to the first recess. A stepping motor type instrument characterized by the following.