JPH0733586Y2 - Stator laminated anti-vibration stepping motor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a stepping motor, and more particularly to a stator laminated vibration-proof stepping motor suitable for automatic assembly.

[Prior Art and Problems] Conventionally, a stepping motor has a structure in which a stator and a rotor are arranged in a housing and are laminated by using screws or the like. Therefore, the respective stator cores are restricted by the screws and the like, and the stator cores do not come into contact with each other.

However, various techniques have been proposed for forming a stator core by stacking a plurality of layers, for example, using a claw pole structure without using screws or the like in consideration of automation of lamination. In the case of such a technique, there is a problem in that the coils and the like that form the stator vibrate due to excitation, and noise is generated by the members of the laminated stator cores. In order to solve this, there is a technique in which a vibration damping damper is arranged between stacked stator cores.

According to this technology, it is effective for vibration isolation, but in automatic assembly, the number of steps for installing the vibration isolation damper increases and
There is a problem in that the anti-vibration damper must be positioned and accurately arranged. Therefore, there is a demand for a stepping motor suitable for automatic assembly, capable of reliably performing vibration isolation and preventing noise without increasing the number of components.

An object of the present invention is to provide a stepping motor, which is suitable for automatic assembly, having a structure for preventing noise generated by the upper and lower laminated stator cores.

Another object of the present invention is to provide a stator laminated type vibration-proof stepping motor that can efficiently and practically perform automatic assembly.

[Means for Solving the Problems] The present invention has been made to solve the above problems, and a laminated stator stepping motor according to the present invention includes a stator and a rotor between an upper housing and a lower housing. In the laminated stepping motor provided, the stator is a stator core having convex magnetic poles, and at least two layers of a coil sandwiched between the stators are laminated and positioned in the lower housing. With one concave stator core having a circular magnetic pole,
A projecting stator core having a plurality of coils and projecting magnetic poles is laminated on the concave stator core, the coil is composed of a bobbin, a winding and a terminal, and the bobbin has a side surface provided with a mounting portion for the terminal, And a side surface not having a terminal mounting portion, and winding is provided between these side surfaces, and a thin damper projection is provided on the side surface having the terminal mounting portion together with a projection higher than the plate thickness of the projecting stator core. At least one protrusion having a thickness lower than the plate thickness of each stator core is formed on a side surface of the stator core, the side surface not having the mounting portion of the terminal, and the plurality of coils and the protrusion stator core stacked in the one concave stator core. The height is higher than the upper end surface of the concave stator core.

Further, it is more preferable to provide one or a plurality of ribs on the inner wall of the lower housing.

[Operation] In the stator laminated vibration-damping stepping motor according to the present invention, a thin damper projection is formed on a side surface of the bobbin forming the coil, the side having a mounting portion of the terminal, and the coil in the concave stator core and the projecting stator core. Since the stacking height of the above is formed higher than the upper end surface of the concave stator core, one housing is pressed against the other housing in order to join the upper housing and the lower housing. Each member constituting the stator will come into close contact with each other, and due to the vibration of the coil due to the excitation of the coil, each member constituting the stator will come into contact with each other at a gap portion to generate abnormal noise or noise. Disappears.

Further, in the lamination of the stator, when the coils are laminated so that the side surfaces having the terminals are close to each other, the damper projections are located on the respective bobbin sides of the portions where the protruding stator cores directly contact each other due to the lamination. It is possible to efficiently absorb the vibration of the protruding stator cores that are in contact with each other and prevent noise.

Further, the concave stator core is press-fitted by the rib provided on the inner wall of the lower housing, and the concave stator core does not move in the lower housing due to the vibration generated by the excitation of the coil. No vibration occurs between

In the stator, if the coil and the projecting stator core are sequentially stacked in one concave stator core, the stator stacking is housed in one concave stator core in advance and then press-fitted into the lower housing. Therefore, it is possible to widen the selection range in the assembling process with respect to the automatic assembling, and the yield is good and the working efficiency is good.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings. It should be noted that the members, arrangements, and the like described below do not limit the present invention and can be variously modified within the scope of the gist of the present invention.

As shown in FIG. 1 and FIG. 2, the stepping motor M of the present embodiment has one concave stator core 14 having two housings 11 and 12 and a protruding magnetic pole forming a stator.
And a projecting stator core 15 having projecting magnetic poles and a coil 16
And the rotor 19 as main constituent members, and in this example, the plate 18 and the outer gear 21 and the internal gear 22 that configure the reduction gear 20 are assembled.

Output side housing (upper side in FIGS. 1 and 2
Hereinafter, referred to as an “upper housing” 11 has a hole 11 for exposing an outer gear 21 which constitutes a reduction gear device 20 described later.
a is formed, and the outer gear
A rib 11b is formed to regulate the lower gear 21a of the gear 21, and a bearing portion 11c formed of a recess for receiving a protruding shaft 18b that supports the internal gear 22 and an internal gear 22 are formed on the inner side of the hole 11a. A regulating rib 11d is formed. Further, on both outer side portions of the upper housing 11, engagement positioning protrusions 11e and 11e (only one of which is shown) when the stepping motor M is assembled to various devices are formed so as to project laterally. Then, for example, as shown in FIG. 6, it is assembled and used in the engagement holes 31, 31 formed in the frame 30 of the rangefinder.

A housing located on the side opposite to the output side (see FIGS. 1 and 2).
The lower side in the figure, hereinafter referred to as the "lower housing") 12
Comprises an extending portion 12a and a cylindrical concave portion 12b which is continuous with the extending portion 12a and accommodates the stator. A bearing concave portion 12c (see FIG. 2) is formed in the central portion of the concave portion 12b. Has been done. Then, two positioning protrusions 12d (only one is shown) are provided at predetermined positions on the bottom surface on the side wall side in the cylindrical recess 12b.
Are formed. Further, ribs 12h are formed to project in the vertical direction on the side wall inside the cylindrical recess 12. In this example, the three ribs 12h are provided at substantially equal intervals, but as will be described later, the concave stator core 14 is provided in the concave portion 12.
The number of the ribs 12h is not limited to three in this example as long as the concave stator core 14 is retained in the concave portion 12 with a sufficient press-fitting force when it is fitted. On the side opposite to the extension 12a, a cutout 12e for positioning the terminal 13 is formed.
Are formed.

Further, a groove 12g for supporting the terminal 13 is formed in the notch 12e for positioning the terminal 13.

The terminal 13 used in this example has a groove 12g formed in the notch 12e of the lower housing 12 in which the inner portion connected to the coil 16 is thicker than the end portion extending outside the housing 12. It is configured to match the shape of the groove portion 12g so as to match. Further, four projections 12f, 12f, for engaging with the holes of the upper housing 11 and attaching by heat caulking are formed on the upper surfaces of the four corners of the lower housing 12. The stator is a concave stator core. It has a so-called claw pole structure composed of 14, a projecting stator core 15 and a coil 16, and in this example, it is composed of two layers, an upper layer stator core A and a lower layer stator core B. The upper layer stator core A is laminated so as to sandwich the coil 16 between the projecting stator cores 15, and the lower layer stator core B is formed by sandwiching the coil 16 between one concave stator core 14 and one projecting stator core 15. . That is, there is one concave stator core 14 on the lower housing 12 side.
Is a predetermined number (6 in this example) of magnetic poles 14a formed at regular intervals (60 ° in this example) by sheet metal working toward the inside of the recess. The height of the recessed stator core 14 is the coil 16 or the protruding shape. It is formed to be slightly lower than the stacking height when the stator core 15 is stacked.

The protruding stator core 15 has the same number of magnetic poles 15a as the magnetic poles 14a formed by sheet metal working at regular intervals (60 ° in this example).

The concave stator core 14 is formed with a cutout portion 14b for positioning the terminal 13, and also has a positioning hole 14b.
c, 14d ... are formed in two places at intervals of 82.5 ° and 97.5 °. The holes 14c and 14d are formed with different diameters, and in this example, the hole 14c has a large diameter. The positioning hole 14c is formed on the wall side of the position of the magnetic pole 14a, and the hole 14c engages with two projections 12d formed on the lower housing 12 at a predetermined position and other 2 holes 1
4d engages with two protrusions 17f formed on the bobbin 17 of the coil 16 described later.

In the projecting stator core 15, two engaging holes 15b, 15b facing each other at 180 ° are formed biased to one magnetic pole side of 7.5 ° between the magnetic poles 15a, and at a predetermined position on the outer circumference (that is, in the present example, the above-mentioned engaging Notch 12e of lower housing 12 when stacking
Two notches 15c are formed at 82.5 ° to the side). These engaging holes 15b are fitted with engaging protrusions 17e formed on the bobbin 17 of the coil 16 described below, and the cutout portions 15c are formed.
Is the engaging projection 1 formed on the mounting portion 17c of the terminal 13.
Engage with 7d. And the magnetic pole (pole tooth) 14a of the stator core
And 15a so that the phase difference between them is 30 °.

The formation position of the cutout portion 15c provided in the projecting stator core 15 in the above described example may be configured as follows. That is, the cutout portion of the lower housing 12 that is perpendicular to the line connecting the two engagement holes 15b and 15b and is stacked.
Notches 15c, 15c are formed at positions separated by 1.35 mm in both directions from the point where the line drawn to the 12e side intersects with the circumference of the stator core 15.

The coil 16 of this example includes a bobbin 17, a conductive wire 16a, and a terminal 13. The bobbin 17 consists of a side surface 17a on which the terminal 13 is mounted and a side surface 17b on which the terminal 13 is not mounted.
The conductor 16a is wound between the side surfaces 17a and 17b, and the end of the conductor is wound around the terminal 13. A mounting portion 17c for mounting the terminal 13 is formed on the side surface 17a on which the terminal 13 is mounted, and one engaging protrusion 17d higher than the thickness of the projecting stator core 15 is formed inward of the mounting portion 17c. There is. In addition, the upper surface of the side surface 17a having the terminal 13 (first
(Fig.) Shows a protrusion 17e higher than the thickness of the protruding stator core 15.
And one thin projection damper projection 17g. In this example, one of the two damper protrusions 17g is provided in the vicinity of the above-mentioned protrusion 17e, and the rest are provided at positions separated by about 180 degrees. The height of the damper protrusion 17g is set from the following viewpoints. That is, the upper and lower stator cores A and B
When heat-caulking the upper housing 11 and the lower housing 12 by stacking the above, a gap is generated between the upper housing 11 and the lower housing 12 due to the damper protrusion 17g. However, as will be described later, since the bobbin 17 uses a member having a certain degree of elasticity such as engineered plastic, the upper housing 11 is pressed toward the lower housing 12 side to join the two housings 11 and 12, Thermal caulking can be performed. The height of the damper protrusion 17g is, as described above,
When the upper housing 11 and the lower housing 12 are assembled, the pressing force that exceeds the elastic force of the bobbin 17 is
It is set so that it can be joined to the extent that it does not overlap with 17.

As described above, after the upper layer stator core A and the lower layer stator core B are stacked in the lower housing 12,
When the plate 18 is placed on the upper layer stator core A and the upper housing 11 is fixed to the lower housing 12,
The upper and lower stator cores A and B have sufficient lower stator 12
This is to make it sink into the interior.

On the other hand, two protrusions 17f, 17f smaller than the thickness of the concave stator core 14 are formed on the side surface 17b of the lower stator core B which does not have the terminal 13, and the lower housing 12 formed on the concave stator core 14 is formed. It engages with the holes 14d, 14d which are not engaged with the projection 12d.

Then, one concave stator core 14, a coil 16 and a projecting stator core 15 are sequentially stacked in the concave stator core 14 to form a lower layer stator core B, and the coil 16 is provided between the projecting stator cores 15 constituting the upper layer stator core A.
Are sequentially stacked so as to hold the upper stator core A on the lower stator core B. At this time, the protruding stator core of the lower layer stator core B and the protruding stator core 15 of the lower layer side of the upper layer stator core A respectively have magnetic poles.
The surfaces on which 15a are not formed are formed back to back.

Further, a plate 18 is arranged between the upper housing 11 and the lower housing 12. This plate 18
Has substantially the same outer shape as that of the lower housing 12, and is made of a material containing carbon, for example, in this example, polyphenylene sulphite 70% and carbon 30%.
It also serves as 19 bearings. That is, the plate 18 is formed with a hole 18a serving as a bearing for the rotor 19, and the hole 18a is formed.
At the side of the internal gear 22
A boss 18c that supports the internal gear 22 is formed on the base of the protruding shaft 18b and the protruding shaft 18b that pivotally support the. Further, on the side portion of the boss portion 18c, the protruding shaft 1 that pivotally supports the outer gear 21
A boss portion 18e that supports the 8d and the outer gear 21 is formed. An annular rib (not shown) is formed on the surface of the stator of the plate 18 (that is, the surface opposite to the surface on which the gears forming the speed reducer 20 are disposed) centering on the hole 18a serving as a bearing. Has been done.

The rotor 19 of this example includes a rotor body 19a made of a plastic magnet and a rotor shaft 19b formed integrally with the rotor body 19a. A gear portion 19c is formed on the output side of the rotor shaft 19b, that is, on the end portion side of the rotor shaft on the plate 18 side. This gear portion 19c is used in the speed reducer 2 described below.
It meshes with the lower gear 22a of the 0 internal gear 22.

The reduction gear device 20 is composed of an internal gear 22 and an outer gear 21, and the internal gear 22 has a lower gear 22a having teeth formed on the inner peripheral side and an upper gear 22b formed on the upper surface of the lower gear 22a. And the upper gear 21b which is meshed with the upper gear 22b of the internal gear 22, and the upper gear 21b is integrally formed above the lower gear 21a. , The upper gear 21b
The upper housing 11 is disposed so as to be exposed from the hole 11a. The internal gear 22 includes the protruding shaft 18b of the plate 18 and the boss portion 1
The outer gear 21 is rotatably supported by 8c, and the outer gear 21 is a protruding shaft 18b of the plate 18.
And is pivotally supported by the boss portion 18c.

Next, the assembling of each member having the above configuration will be described. To assemble, first, the other constituent members of the lower layer stator core B are sequentially stacked in one concave stator core 14, and further, the respective constituent members of the upper layer stator core A are sequentially stacked. Then, the rotor 19, the plate 18, the reduction gear 20, and the upper housing 11 are laminated in this order. This will be described in more detail. First, the coil 16 is placed in one concave stator core 14, and the protrusion 17f formed on the bobbin 17 is engaged with the hole 14d of the concave stator core 14. Next, the protruding stator core 15 is laminated. At this time, the engaging hole 15b of the protruding stator core 15
And the protrusion 17e of the bobbin 17 are aligned with the notch 15c of the projecting stator core 15 and the engaging protrusion 17d formed on the mounting portion 17c of the terminal 13. As a result, the lower layer stator core B is assembled, and each magnetic pole 14a of the concave stator core 14 and each magnetic pole 1 of the projecting stator core 15 are assembled.
5a can be arranged at regular intervals (30 ° in this example).

Next, the upper layer stator core A is assembled, but first, the projecting stator core 15 is placed on the projecting stator core 15 forming the lower layer stator core B described above and in the opposite direction to the projecting stator core 15 forming the lower layer stator core B. That is, the magnetic pole is placed on top. At this time, the protruding stator core
The engaging holes 15b of the fifteen and the protrusions 17e of the bobbin 17 constituting the lower layer stator core B are fitted together, and the notches 15c of the projecting stator core 15 and the mounting portion 17c of the terminal 13 constituting the lower layer stator core B are formed. The protrusion-shaped stator core 15 is positioned by being combined with the engagement protrusion 17d.

Next, the coil 16 is placed. At this time, the coil 16 and the projecting stator core 15 are assembled in the same manner as when the lower layer stator core B is laminated. That is, the engagement hole 15b that is not engaged with the protrusion 17e of the bobbin 17 that constitutes the lower layer stator core B,
Together with the protrusion 17e (not shown on the upper stator core side) of the bobbin 17 that constitutes the upper stator core A,
The protruding stator core 15 is positioned by combining the cutout portion 15c of the protruding stator core 15 and the engaging protrusion 17d formed on the mounting portion 17c of the terminal 13.

Further, the projecting stator core 15 is placed with the magnetic poles facing down. By doing so, the upper-layer stator core A also has the magnetic poles 15a of the projecting stator cores 15 spaced at regular intervals (30 in this example).
°) can be placed. Therefore, the magnetic poles of each of the four stator cores can be stacked at positions displaced by a constant distance (15 ° in this example).

Then, the rotor 19 is inserted through the washer 23 from the rotor shaft 19b side without the gear 19c.

Next, the upper layer stator core A laminated as described above.
And the lower layer stator core B is press-fitted into the lower housing 12. At this time, the notch 14b of the concave stator core 14 is
The projection 12d of the housing and the hole 14c of the concave stator core 14 are engaged with each other toward the notch 12e of the lower housing 12. As described above, the recessed stator core 14 is formed with the holes 14c and 14d. However, since the diameter of the hole 14c is larger than the hole 14d, the assembly can be done without any mistake.

Next, the plate 18 is placed. At this time, in this example, the projecting stator core 15 located on the uppermost side of the stacked stators is located closer to the plate 18 than the upper end of the concave stator core 14, and the ribs 18f formed on the plate 18 are projecting. It contacts the upper surface of the stator core 15.

Next, the internal gear 22 is pivotally supported by the protruding shaft 18b, and the lower gear 22a of the internal gear 22 and the gear 19c of the rotor 19 are meshed with each other. Then, use the outer gear 21 and the protruding shaft 18d.
Support with. At this time, the upper gear 22 of the internal gear 22
The lower gear 21a of the outer gear 21 is meshed with b.

Finally, the upper housing 11 is placed, and the upper and lower housings 11 and 12 are thermally caulked to integrate the upper and lower housings.

Here, when the plate 18 and the lower housing 12 are joined, as described above, the laminated portion of the projecting stator 15 on the plate 18 side is slightly smaller than the upper end of the concave stator core 14 on the plate 18 side. However, since the upper housing 11 is mounted and before the upper and lower housings 11 and 12 are thermally crimped, a slight gap is naturally generated between the upper housing 11 and the lower housing 12. There is. However, as described above, since the bobbin 17 is formed of a member having elasticity, the upper housing 11 is replaced by the lower housing.
If you push it to the 12 side, the upper housing 11 and the lower housing
12 and 12 can be easily joined, and heat caulking may be performed in this state. Then, since the upper and lower housings 11 and 12 are thermally crimped in a state in which a slight pressing force is applied to the bobbin 17 in this manner, the members constituting the respective stators are almost in close contact with each other inside the housings 11 and 12. In particular, the joint portion between the projecting stator core 15 forming the upper layer stator core A and the projecting stator core 15 forming the lower layer stator core B in the back-to-back state is surely brought into close contact with each other.

In particular, in the above-mentioned embodiment, the protruding stator core 15 is attached to the plate 18.
Since the ribs projecting inward are formed, the plate 18 and the lower housing 12 are assembled with each other in a state in which a pressing force is further applied.

In the above-described embodiment, an example in which two damper protrusions 17g are provided on the side surface 17a of the bobbin 17 is shown, but the number of the damper protrusions 17g is not particularly limited to two. For example, although one may be provided, in this case, the gap between the side surface 17a of the bobbin 17 and the projecting stator core 15 is not uniform, so that the effect is slightly inferior to the above-described two embodiments. Therefore, it is desirable to provide two or more damper protrusions 17g. Also, the shape of the damper protrusion 17g is not particularly limited.

The stepping motor M described in the above embodiment is
Although the description has been given using the one in which the speed reducer 20 is integrally formed,
The anti-vibration stepping motor of the laminated stator type according to the present invention may be configured without the speed reducer 20. For example, when such a speed reducer is not provided, an upper housing corresponding to the plate 18 is used, and in this case, an upper housing having no space for disposing the speed reducer is used. That is, a rib corresponding to a ring-shaped protruding rib (not shown) centered on the hole 18a serving as a bearing formed in the plate 18 is formed on the surface of the upper housing facing the lower housing 12,
The output shaft 19 extends from the upper housing. The extended output shaft and the known speed reducer can be separately attached as in the known art.

[Advantages of the Invention] Since the present invention is configured as described above, in the stator laminated vibration damping stepping motor according to the present invention, the lamination height of the coil in the concave stator core and the protruding stator core is the concave stator core. Since it is formed higher than the upper end surface of the stator and one of the housings is pressed against the other housing in order to join the upper housing and the lower housing, the respective members constituting the stator come into close contact with each other. By virtue of the vibration of the coil due to the excitation of the coil, the members constituting the stator do not come into contact with each other at the portion where the gap is formed, and no abnormal noise or noise is generated.

Further, in the lamination of the stator, when the coils are laminated so that the side surfaces having the terminals are close to each other, the damper projections are located on the respective bobbin sides of the portions where the protruding stator cores directly contact each other due to the lamination. It is possible to efficiently absorb the vibration of the protruding stator cores that are in contact with each other and prevent noise.

In addition, the ribs projecting from the inner wall of the lower housing prevent the concave stator core from moving in the lower housing and thus prevent vibration between the stator core and the housing.

Since the stator has a structure in which the coil and the projecting stator core are sequentially stacked in one concave stator core, the stator stacking is housed in one concave stator core in advance and then press-fitted into the lower housing. Therefore, it is possible to widen the selection range in the assembling process with respect to the automatic assembling, and the yield is good and the working efficiency is good.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of a stepping motor according to the present invention, and FIG. 2 is a vertical sectional view of the stepping motor. 11 ... Upper housing, 12 ... Lower housing, 12h ... Rib, 14 ... Concave stator core, 14a, 15a ... Pole teeth (pole), 1
4c ... Positioning hole, 15 ... Projected stator core, 15b ... Positioning hole (engagement hole), 16 ... Coil, 17e, 17f ... Positioning projection (projection), 17g ... Damper projection, A ... Upper layer stator core, B ... Lower layer Stator core.

Claims (2)

[Scope of utility model registration request] 1. A laminated type stepping motor in which a stator and a rotor are arranged between an upper housing and a lower housing, wherein the stator is a stator core having convex magnetic poles and at least two layers of a coil sandwiched between the stator cores. Then, the stator is provided with one concave stator core having projecting magnetic poles, and the projecting stator core having a plurality of coils and projecting magnetic poles is laminated on the concave stator core. The coil is composed of a bobbin, a winding wire, and a terminal, and the bobbin has a side surface with a terminal mounting portion and a side surface without a terminal mounting portion, and the coil is wound between these side surfaces. A wire is provided, and a thin damper with a protrusion higher than the plate thickness of the projecting stator core is provided on the side surface provided with the mounting portion of the terminal. At least one protrusion having a thickness lower than the plate thickness of each of the stator cores is formed on a side surface of the stator core, the side surface of which is not provided with the mounting portion of the terminal. A laminated stator stepping motor according to claim 1, wherein the laminated height is higher than the upper end surface of the concave stator core. 2. The stator laminated vibration damping stepping motor according to claim 1, wherein one or more ribs are provided on the inner wall of the lower housing so as to project therefrom.