JPS6237051A - Stepping motor - Google Patents

Abstract

PURPOSE:To increase the number of turns for windings, and to improve the characteristics of a motor by directly winding or fitting first and second exciting coils on the outer circumferences of magnetic pole sections for first and second yokes without a bobbin. CONSTITUTION:First and fourth yokes 1-4 are each formed by stamping an iron plate by a press. First and second exciting coils 5, 6 are each disposed in such a manner that they are wound directly on the outer circumferences of respective magnetic pole section 1a, 4a for the first and fourth yokes 4 without a bobbin or previously wound doughnut-shaped coils having no bobbin are fitted. The first - fourth yokes 1-4 are bonded integrally through spot welding, etc.

Description

[Detailed description of the invention] B1 Purpose of the invention [Industrial application field] The present invention relates to stepping motors.

[Conventional technology]

3-4 are a longitudinal sectional front view and an exploded perspective view of a conventional general stepping motor.

In the figure, 20 is a plate for external mounting on the motor side that is connected with screws or the like to the chassis, etc. (not shown) of devices that use a stepping motor, 21 is a first yoke, 22 is a second yoke, and 23 is a third yoke. yoke, 24 is the fourth yoke, 25 is the first excitation coil wound around the pobbin 25a, 26 is the pobin 26a
27 is a rotor magnet (permanent magnet rotor) having a plurality of magnetic poles, 29.
Reference numeral 30 denotes a rotor bearing provided on the first yoke 21, a connector for connecting the first excitation wire, . , a connector that connects the second excitation coil 6 and an external conductor (not shown) to each other.

For external mounting, use plate 20. 1st to 4th yokes 21, 22, 23
・24 are press punched parts made of iron plates.

The first yoke 21 and the fourth yoke 24 each have a circumferential wall 21
b and 24b, and eight equally spaced cut and raised pole teeth 21a and 24a as magnetic poles are provided on a circle concentric with the central axis of the yoke. The rotor bearing 2 is formed by press punching into a chalet shape.
9.31 and connector 30@32 are retrofitted.

The second yoke 22 and the third yoke 23 have six rotor fitting holes 22b and 23b, which are aligned with the center axis of the yoke, and eight equally spaced pole teeth 22a and 23 as magnetic poles on the edges of the holes.
It is press punched into a disc shape with a.

The IT yoke 21 and the second yoke 22 are connected to each other's pole teeth 21.
a and 22a are inserted in an interlocking manner alternately. Similarly, the third yoke 23 and the fourth yoke 24
and are combined with the pole teeth 23a and 24a being fitted into each other in an interlocking manner.

The winding end of the bobbin 25a around which the first excitation coil 25 is wound is connected to the terminal 30a of the connector 30, the bobbin 25a is fitted and stored in the first yoke 21, and the connector 30
The connector is attached to the circumferential wall of the first yoke 21, the second yoke 22 is assembled to the first yoke 21, and both yokes 21 and 22 are joined together by spot welding, adhesive, or the like.

Similarly, the winding end of the bobbin 26a around which the second excitation coil 26 is wound is connected to the terminal 32a of the connector 32, the bobbin 26a is fitted and housed in the fourth yoke 24, and the connector 32 is connected to the fourth yoke 24. The connector is attached to the circumferential wall of the connector, and the third yoke 23 is combined with the fourth yoke 24 to connect both yokes 23 and 24 together.

The assembly of the first and second yokes 21 and 22 and the assembly of the third and fourth yokes 23 and 24 are assembled, and the rotor 27 is inserted into the inner space of both of them, and both end shafts 27a and 27a are respectively attached. The second yoke 22 and the third yoke 23, which are placed back to back, are integrally connected by inserting the bearings into the bearings 29 and 31 and putting them in a built-in state. For external mounting, the entire motor is assembled by integrally connecting the plate 20 and the first yoke 21.

There is also a procedure in which the second yoke 22 and the third yoke 23 and the first yoke 21 and the externally attached plate 20 are integrated by spot welding or the like in advance, and then the entire motor is assembled.

[Problem that the invention seeks to solve]

In the conventional motor as described above, the first and second excitation coils 25 and 26 are housed in the pot bins 25a and 26a1 and the fourth yokes 21 and 24, respectively.
The insides of the first and fourth yokes 21 and 24 are narrowed by storage bins 25a and 26a, and in particular, the insides of the first and fourth yokes 21 and 24 are considerably pinched due to the thickness of the winding cylindrical portion (winding drum) of the bobbin, so that the excitation coils 25 and
26 and the connectors 30-32 are reduced, and as a result, the amount of winding of the excitation coils 25 and 26 is limited, resulting in a reduction in motor characteristics.In addition to disadvantages such as the lack of installation space, it is difficult to assemble the motor. However, due to the structure, it is not possible to wind the wire without a pobbin for connecting the winding wire and the connector, and there are many problems in general, such as the cost of materials, parts, and assembly manufacturing cost being relatively high due to the large number of parts.

The present invention has been proposed in view of the above, and aims to eliminate all of the above-mentioned problems by making this type of motor pobin-less and reducing the number of parts by making the component parts dual-purpose parts. purpose.

B. Structure of the Invention [Means for Solving Problems] The present invention includes a magnetic pole part, a rotor bearing part, a connector for connecting an excitation coil and an external conductor, and an external mounting part. The external mounting includes a first yoke that also serves as a plate, a second yoke that is combined with the first yoke and has magnetic pole parts arranged alternately with the magnetic pole parts on the first yoke side, and a third yoke that has magnetic pole parts. , a fourth yoke that is combined with the third yoke and has magnetic pole parts arranged alternately with the magnetic pole parts on the third yoke side, a rotor bearing part, and a connector for connecting the excitation coil and the external conductor. a yoke, a first excitation coil without a bobbin arranged around the outer circumference of the magnetic pole parts of the combined first and second yokes, and arranged around the outer circumference of the magnetic pole parts of the combined third and fourth yokes. a second excitation coil without a bobbin; and a permanent magnet rotor that is supported between the bearings of the first and second yokes and is built inside the first to fourth yokes.

The gist is a stepping motor characterized by the following.

[For production]

That is, the first excitation coil and the second excitation coil are constructed by winding wires directly around the outer circumferences of the magnetic pole portions of the first yoke and the second yoke, respectively, without a bobbin, or by winding them in a donut shape without a bobbin, which are pre-wound. The bobbin is omitted by fitting the molded coil around the outside of the first yoke and the second yoke, which expands the winding space and allows for more windings than the conventional structure with bobbins. It becomes possible to provide a coil with a large amount of radiation, and the motor characteristics can be significantly improved.

Furthermore, the expansion of the winding space makes it easier to assemble each connector into the first and fourth yokes.

Furthermore, by not having a bobbin and by using both the plate and the first yoke for external mounting, the number of parts can be reduced, and the cost of materials and parts can be reduced.1 Assembly costs can be reduced by simplifying the assembly manufacturing system. .

〔Example〕

1 and 2 are a longitudinal sectional front view and an exploded perspective view of an embodiment of a stepping motor according to the present invention.

In the figure, 1 is a first yoke that is externally mounted and also serves as a plate, 2 is a second yoke, 3 is a third yoke, 4 is a fourth yoke, 5 is a first excitation coil, 6 is a second excitation coil, and 7 is a plurality of It is a rotor magnet (permanent magnet rotor) with magnetic poles.

The first to fourth yokes 1, 2, and 3 yokes 4 are press punched parts of iron plates, respectively.

In the first yoke 1, 1a denotes eight equally spaced pole teeth 8.8 as magnetic pole parts cut and raised concentrically with the central axis.
For external mounting, there are punched holes for inserting mounting screws, etc. 9.1O is the rotor bearing and connector, and the parts are retrofitted. 10a is a terminal of the connector 10.

In the second yoke 2, reference numeral 2a indicates eight equally spaced pole teeth as magnetic pole parts cut and raised on the edge of the rotor insertion hole 2b, which is concentric with the center axis, 2C is a circumferential wall, and 2d is a notch in the circumferential wall. This is the fitting escape part of the formed connector 10.

The first and second yokes l-2 each have pole teeth 1a and
2a are inserted in an interlocking manner alternately.

In the third yoke 3, reference numeral 3a indicates eight equally spaced pole teeth as a magnetic pole section formed by cutting and raising the edge of the rotor insertion hole 3b concentric with the central axis, 3C indicates a circumferential wall, and 3d indicates a cutout in the circumferential wall. This is a fitting escape portion of the connector 12 on the fourth yoke 4 side, which will be described later.

This third yoke 3 can be manufactured using the same press die as the second yoke 2.

In the fourth yoke 4, reference numeral 4a denotes eight equally spaced pole teeth as a magnetic pole section cut and raised concentrically with the central axis.

11@12 is a rotor bearing and a connector, and the parts are retrofitted. 12a is a terminal of the connector 12.

The third and fourth yokes 3 and 4 are connected to each other's pole teeth 3a and 4.
4a are assembled in a state in which they are fitted in an interlocking manner alternately.

The first and second excitation coils 5 and 6 are linearly wound around the outer circumferences of the magnetic pole parts 1a and 4a of the first yoke l and the fourth yoke 4, respectively, without a bobbin, or are pre-wound. Arranged by fitting a donut-shaped coil without a bobbin,
The terminals of those coils 5 and 6 are connected to connectors lOΦ12.
Connect to the terminals 10a and 12a of the connectors 10
- The connectors 12 of the first yoke l and the fourth yoke 4 are attached to the portions 1d-4d, respectively.

Then, the second yoke 2 is combined with the first yoke 1, and both yokes 1 and 2 are integrated by spot welding, etc. Similarly, the third yoke 3 is combined with the fourth yoke 4, and both yokes 4 and 2 are integrated. 3 are integrated, and the rotor 7 and both end shafts 7aφ7a are inserted into the bearings 9-11 respectively, and the rotor 7 is built into the inner space of the two, and the second yoke 2 and the second yoke 2 are placed back to back. The entire motor is assembled by integrally joining the third yoke 3 with spot welding or the like.

C. Effects of the Invention As described above, according to the present invention, the stepping motor is bobbinless and has a large number of winding turns, so the motor characteristics are good, and the number of parts is small, so the cost of materials and parts is reduced, and assembly and manufacturing It is possible to reduce the assembly cost by simplifying the system, and the intended purpose is well achieved.

[Brief explanation of the drawing]

1 and 2 are a longitudinal sectional front view and an exploded perspective view of an embodiment of a motor according to the present invention, and FIGS. 3 and 4 are a longitudinal sectional front view and an exploded perspective view of an example of a conventional motor. 1-2-3-4 are the first to fourth yokes, lag2a/3
A and 4a are cut and raised pole teeth as magnetic pole parts, 5-6 are first and second excitation coils, and 7 is a rotor magnet.

Claims (1)

[Claims] (1) A first yoke that also serves as an external mounting plate and has a magnetic pole part, a rotor bearing part, a connector for connecting an excitation coil and an external conductor, and an external mounting part, and is combined with the first yoke. , a second yoke having magnetic pole portions arranged alternately with the magnetic pole portions on the first yoke side; a third yoke having magnetic pole portions; and a second yoke combined with the third yoke and having magnetic pole portions on the third yoke side. a fourth yoke having alternately arranged magnetic pole parts, a rotor bearing part, and a connector for connecting the excitation coil and the external conductor; a first excitation coil without a bobbin disposed around the magnetic pole portions of the combined third and fourth yokes; a second excitation coil without a bobbin disposed around the outer circumference of the magnetic pole portions of the combined third and fourth yokes; A stepping motor comprising: a permanent magnet rotor supported between bearings and housed within the first to fourth yokes.