JPH0150183B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a toroidal coil type rotating electric machine.

Generally, a toroidal coil type rotating electrical machine has a ring-shaped iron core, for example, if it has a four-pole configuration, about
It consists of an armature having four toroidal coils divided at 90° intervals, and a field having magnetic poles separated by a certain gap for each coil. It is configured to generate magnetic flux from the magnetic poles to the annular core of the armature in the radial direction. In this four-pole example, the magnetic poles of the field are alternately different in the order of N pole, S pole, N pole, and S pole. The four coils of the corresponding armature are also wound in such a way that the winding directions are alternately reversed. Assuming that this armature coil is also connected to the series,
When a certain magnitude of current is passed through this coil, a torque is generated between the field and the armature, and this torque is proportional to the magnitude of the current, and the direction of the torque is determined by the direction of the current. Let us now consider a case where the armature is on the outside and the field is on the inside, and the armature is used as a stator and the field is used as a rotor. Such a toroidal coil rotating electrical machine is usually used when the rotation range of the rotor is limited to a certain angle, for example, within a range of plus or minus 20 degrees around a reference position. Examples of applications include control of hydraulic rotary valves, and servo motors in limited range rotation servo systems. For such applications, toroidal coil type rotating electric machines are very convenient because they do not have any commutators or slip rings, so even though they are DC machines, they do not have frictional torque or consumable parts like AC induction machines.

On the other hand, this type of toroidal coil type rotating electrical machine has the property that the magnitude of torque generated by the same current changes depending on the relative positional relationship between the field and the armature. Figure 1 is a diagram that generally explains this property. The angle reference position is when the center of each magnetic pole of the field is at the center of each toroidal coil, and the horizontal axis shows the field and armature. The relative rotation angle θ is plotted, and the vertical axis plots the torque when the current is set to a certain constant value. When the rotation angle θ is zero, that is, at the reference position mentioned above, the generated torque is the maximum value τm, but as θ goes to the left or right, the torque decreases, and the number of poles decreases to P. Then,
The torque becomes zero when θ is π/P radians. In the above example, since P is 4, the torque becomes zero when θ is 45°. Normally, in this type of toroidal coil type rotating electric machine, the specifications specify how much of the maximum value τm the torque can fall within the range of angles used, for example, plus or minus 20 degrees, and the torque is adjusted accordingly. Designed with In FIG. 1, the limit of torque attenuation is generally defined at this point by assuming that when θ is θf, the torque is τf.

The above is an example of a torque motor, which is a 4-pole toroidal coil type rotating electrical machine, but the number of poles ranges from 2 to a considerable number of poles, and the field is fixed. In some cases, the armature is the rotor.

In addition, toroidal coil type rotating electric machines are sometimes used as tachometers instead of torque motors, and in this case, no current is applied to the armature from the outside, and instead a voltage is proportional to the relative angular velocity of the field to the armature. utilizes the property of generating electricity from a toroidal coil. In this case, if we take the generated voltage for a constant angular velocity instead of the torque as the vertical axis in FIG. 1, we will see a curve that is exactly the same as that described for the torque. In this case, the generated voltage for a certain angular velocity at θf is defined as a specification.

Generally, in this type of toroidal coil type rotating electrical machine, it is necessary to leave a certain angular range of space without coils between each toroidal coil. Conventionally, in order to obtain the space _ts between the coils, the annular core was accurately marked,
Using this as a guide, each toroidal coil was wound to create a designated space. However, such conventional methods have the drawback that when each coil is wound in multiple layers, the windings may collapse or shift, resulting in a problem that a predetermined space _ts cannot be obtained. The change in the predetermined width t _s of this space means that
This has a significant effect on the curves in Figure 1. That is, this type of toroidal coil type rotating electric machine has a serious drawback in that, for example, when the angle θf is, the desired lower limit torque τf cannot be obtained correctly.

Therefore, the main object of the present invention is to provide a toroidal coil type rotating electrical machine that eliminates the above-mentioned conventional drawbacks.

The gist of the present invention is to provide an armature having a plurality of toroidal coils divided at equal intervals on a ring-shaped core, a field having the same number of magnetic poles as the plurality of toroidal coils, and a field disposed inside the armature. In a toroidal coil type rotating electrical machine consisting of a magnet and a case in which an armature is housed, a central axis of the ring-shaped core is placed on the outer peripheral surface of the ring-shaped core corresponding to each adjacent gap between a plurality of toroidal coils. A step portion is formed on the inner peripheral surface of the case and has a free end surface that abuts one end surface in the direction of the central axis of the ring-shaped core of each projection. A toroidal coil type rotating electrical machine is characterized by the following.

FIG. 2 is an exploded perspective view of an example of a toroidal coil type rotating electric machine according to the present invention, and FIG. 3 is a sectional view taken along a plane perpendicular to the rotation axis O in the assembled state. In the figure, 1 shows the field of the toroidal coil type rotating electrical machine as a whole, 2 shows the armature as a whole, and 3 shows the case.
The example of the present invention shown in FIGS. 2 and 3 is a four-pole case, in which the field 1 is placed inside the armature 2 and the case 3 is placed on the outermost side. Therefore, in this case, the field 1 is a four-pole protruding field.

As shown in the figure, the field 1 is connected to a ring-shaped yoke 11 made of magnetic material at equiangular intervals (in this case
It consists of four magnets 12, 13, 14 and 15 fixed to the outer circumferential surface of a ring-shaped yoke 11 with a predetermined gap between adjacent ones at an angle of 90 degrees. As is well known, each magnet has substantially the same shape and is magnetized along its thickness direction, that is, along the diameter direction of the ring-shaped yoke 11. For example, if the surface of the magnet 12 is magnetized to the south pole and the inner surface (the surface fixed to the yoke 11) is magnetized to the north pole, the magnet 14 on the opposite side to the yoke 11
are magnetized with the same polarity, but the magnets 13 and 15 between them are magnetized with opposite polarities. In other words, each magnet 12 to 15
are sequentially magnetized with opposite polarities.

On the other hand, the armature 2 includes a ring-shaped core 21 made of a magnetic material such as iron, and four toroidal coils 22, 23, 24 and 2 wound around the core 21.
5, and four protrusions 26, 2 each having a predetermined width _ts fixed to the outer peripheral surface of the ring-shaped core 21 so as to be located between the adjacent toroidal coils 22 to 25.
7, 28 and 29. The ring-shaped core 21 of each toroidal coil 22...25 has the same length in the circumferential direction, and the winding directions thereof are sequentially reversed.

The case 3 has a cylindrical shape made of a thin plate, and the armature 2
When storing the armature in this cylindrical case 3, the inner diameter of the cylindrical case 3 is selected so that the outer periphery of the protrusions 26...29 of the armature 2 is in contact with the inner periphery of the cylindrical case 3. . A thick ring 31 is fixed to the inner peripheral surface near one open end of the cylindrical case 3, and the armature 2
When inserted into the case 3, one end surface of each projection 26...29 in the direction of the central axis O abuts against the free end surface of the ring 31, and the positioning of the armature 2 in the direction of the central axis O is performed. Do as you please. Note that the ring 31 may be formed integrally with the cylindrical case 3, and a step similar to the ring 31 may be formed on the inner peripheral surface of the cylindrical case 3.

Next, the protrusions 26...29, which are one of the main elements of the present invention, will be explained. As shown in the figure, each protrusion 26...29 has substantially the same shape, has a length spanning at least the entire length of the outer peripheral surface of the ring-shaped core 21 in the direction of the central axis O, and has a width of the outer peripheral surface in the circular direction. is a predetermined width _ts , and the length l protruding outward from the outer circumferential surface of the ring-shaped core 21 is determined by taking into consideration the diameter of the conducting wire of the toroidal coil wound around the ring-shaped core 21, the number of layers of the coil, etc. and be selected appropriately. Therefore, when winding each toroidal coil 22...25 around the ring-shaped core 21, each projection 26...29 not only serves as a conventional marking (positioning each coil), but also Since each coil can be reliably prevented from collapsing or shifting, it is possible to wind each coil uniformly and also to have a predetermined length. Furthermore, the spacing between the coils, that is, the space, can be reliably maintained at a predetermined width _ts . Furthermore, the positioning between the armature and the case can be carried out very simply.

In addition, the means provided on the armature to abut against the step portion provided in the case that positions the armature in the direction of the central axis is replaced by a plurality of toroids divided at equal intervals on the ring-shaped core of the armature. Since it also serves as a protrusion provided on the outer peripheral surface of the ring-shaped core for regulating the space between the coils, the structure of the rotating electric machine is simplified.

Therefore, the lower limit torque of the toroidal coil type rotating electric machine can be reliably set to the intended value, and even when this machine is mass-produced, variations in characteristics can be kept to a minimum.

Although the above description describes a four-pole toroidal coil type rotating electric machine, the present invention is not limited to this example, and can of course be applied to a toroidal coil type rotating electric machine with two poles or an even number of poles of six or more poles. is not limited to the above-mentioned salient pole type, but may be of a cylindrical type, for example.

Furthermore, the same effect can be obtained even when the present invention is applied to a type in which the field is disposed outside the armature.

Note that many changes and changes may be made without departing from the gist of the invention.
It will be obvious that modifications may be readily made by those skilled in the art.

[Brief explanation of drawings]

FIG. 1 is a torque distribution diagram of a toroidal coil type rotating electric machine, FIG. 2 is an exploded perspective view of an example of the toroidal coil type rotating electric machine of the present invention, and FIG. 3 is a sectional view showing its assembled state. In the figure, 1 is a field, 2 is an armature, 3 is a case, 11 is a yoke, 12...15 is a magnet, 21 is a ring-shaped core, 22...25 is a toroidal coil, 26...... Reference numerals 29 indicate protrusions.

Claims (1)

[Claims] 1. an armature having a plurality of toroidal coils divided at equal intervals on a ring-shaped core; a field having the same number of magnetic poles as the plurality of toroidal coils and arranged inside the armature; In a toroidal coil type rotating electric machine comprising a case in which the armature is housed, a central axis of the ring-shaped core is provided on the outer peripheral surface of the ring-shaped core corresponding to each adjacent gap between the plurality of toroidal coils. a protrusion extending at least the entire length in the direction of the ring-shaped core, and a free end surface on the inner peripheral surface of the case that abuts one end surface of the protrusion in the direction of the central axis of the ring-shaped core. A toroidal coil type rotating electrical machine characterized by having a stepped section.