JP6794907B2 - Engagement device - Google Patents

Description

The present invention relates to an engaging device capable of switching between an engaged state and an open state by using the polarity reversal of a permanent magnet.

Conventionally, as disclosed in Patent Documents 1 and 2, an engaging device using two types of permanent magnets and an electromagnet has been known. For example, in Patent Document 1, as illustrated in FIG. 13, the polarity fixing magnet 100 which is relatively difficult to magnetize, the polarity variable magnets 102A and 102B which are relatively easy to magnetize, and the coils 104A and 104B for reversing the polarity. The engaging device (brake device) using the above is disclosed.

The polar variable magnets 102A and 102B have coils 104A and 104B wound around them, respectively. The variable polarity magnets 102A and 102B and the coils 104A and 104B are fixed together with the fixed side yoke 106. The fixing ring 107 is provided so that the polarity variable magnets 102A and 102B are in contact with the side surfaces thereof. The fixing ring 107 includes an arc-shaped yoke 108 and a polarity fixing magnet 100 that connects adjacent arc-shaped yokes 108A and 108B. Rotating rings 110 are provided on the inner peripheral surface of the fixing ring 107 with a gap (interval).

FIG. 14 illustrates a diagram in the open state. The magnetic flux of the polarity fixing magnet 100 and the magnetic flux of the polarity variable magnets 102A and 102B are in the forward direction (series), and the combined magnetic flux of both is the polarity variable magnet 102A → arcuate yoke 108A → polarity fixing magnet 100 → arcuate yoke 108B → It passes through the loop path L_OFF of the polarity variable magnet 102B → the fixed side yoke 106 → the polarity variable magnet 102A →.

FIG. 15 illustrates a diagram of the engaged state. This is illustrated when the polarities of the polarity variable magnets 102A and 102B are reversed from the state shown in FIG. 14 by the magnetic field generated from the coils 104A and 104B. At this time, the magnetic flux of the polar variable magnets 102A and 102B passes through the loop path L_ON1 with the fixed side yoke 106 → the polar variable magnet 102B → the arc-shaped yoke 108B → the rotating ring 110 → the arc-shaped yoke 108A → the polar variable magnet 102A. Further, the magnetic flux of the polarity fixing magnet 100 passes through the loop path L_ON2 of the arc-shaped yoke 108B → the rotating ring 110 → the arc-shaped yoke 108A → the polarity fixing magnet 100.

The inner peripheral surfaces of the arc-shaped yokes 108A and 108B and the outer peripheral surface of the rotating ring 110 are formed with irregularities along the circumferential direction. Therefore, the gap between the two is different along the circumferential direction. The magnetic resistance passing through the gap changes according to the fluctuation of the gap. For example, when the convex portions of the inner peripheral surfaces of the arc-shaped yokes 108A and 108B and the outer peripheral surfaces of the rotating ring 110 face each other, the magnetic resistance takes the minimum value, and when the concave portions face each other, the magnetic resistance takes the maximum value. From this state, when the arcuate yokes 108A and 108B and the rotating ring 110 try to rotate relative to each other from the above state, a force for maintaining the magnetic flux acts, and as a result, the rotating ring 110 engages with the fixed ring 107 and rotates. The rotational movement of the ring 110 is stopped.

Japanese Unexamined Patent Publication No. 2016-217371 Japanese Unexamined Patent Publication No. 1-35331

By the way, it is conceivable to apply an engaging device using the polarity reversal of a permanent magnet to the engagement between rotating bodies. For example, in the brake device of FIG. 13, it is conceivable that the fixing ring 107 is rotatable (rotating ring 107') and a magnetic path is formed with the polarity variable magnets 102A and 102B through a predetermined gap.

However, in such a case, as shown in FIG. 16, the polarity is reversed between the polarity variable magnets 102A and 102B, and the polarity of the rotating ring 107 ′ receiving the polarity is also reversed along the circumferential direction (rotational direction). If the polar variable magnets 102A and 102B and the rotating ring 107'move relative to each other in this state, an eddy current is generated along with the change in the magnetic flux, which may hinder the rotation of the rotating ring 107'. Therefore, an object of the present invention is to provide an engaging device capable of suppressing the generation of eddy currents due to rotation as compared with the conventional case.

The present invention relates to an engaging device. The engaging device includes a fixed body, a first rotating body, and a second rotating body. The fixed body is wound between a bobbin having a small-diameter cylindrical portion and a pair of large-diameter annular portions provided at both ends in the axial direction of the small-diameter cylindrical portion, and a pair of large-diameter annular portions of the small-diameter cylindrical portion. It is equipped with a coil. The first rotating body includes a ring-shaped first rotating body yoke having a gap with one outer peripheral surface of a pair of large-diameter ring portions and facing the inner peripheral surfaces, and the other of the pair of large-diameter ring portions. A ring-shaped second rotating body yoke having a gap and facing the inner peripheral surfaces is provided. The second rotating body includes an inner peripheral surface formed so that the gap width with the outer peripheral surface of the first and second rotating body yokes is different along the circumferential direction. At least one of the fixed body and the first rotating body is provided with a first permanent magnet and a second permanent magnet that is easier to magnetize than the first permanent magnet. The magnetic field generated from the coil reverses the magnetic poles of the second permanent magnet, and the magnetic fluxes of the first and second permanent magnets pass through the second rotating body in response to the magnetic pole reversal of the second permanent magnet. The magnetic field of the second permanent magnet can be switched to an open state in which the magnetic field does not pass through the second rotating body. In this configuration, the gap widths between the outer peripheral surfaces of the pair of large-diameter ring portions and the inner peripheral surfaces of the first and second rotating body yokes are formed to be equal along the circumferential direction. Further, between one outer peripheral surface of the pair of large-diameter annular portions and the inner peripheral surface of the first rotating body yoke, and between the other of the pair of large-diameter annular portions and the inner peripheral surface of the second rotating body yoke. Only magnetic fluxes of the same polarity pass along the circumferential direction between them.

Further, in the above invention, the first permanent magnet may be provided on the first rotating body so as to connect the first rotating body yoke and the second rotating body yoke.

Further, in the above invention, the second permanent magnet is provided on a pair of large-diameter ring portions, and is relatively on the outer peripheral side and relatively on the inner peripheral side with one magnetic pole provided along the circumferential direction. It may be provided with the other magnetic pole provided along the circumferential direction.

Further, in the above invention, the second permanent magnet is provided on the first and second rotating body yokes, and is relatively on the outer peripheral side and relatively on the inner peripheral side with one magnetic pole provided along the circumferential direction. It may be provided with the other magnetic pole provided along the circumferential direction.

In another aspect of the engaging device of the present invention, the engaging device includes a fixed body, a first rotating body, a second rotating body, and a guide member. The fixed body is wound between a bobbin having a small-diameter cylindrical portion and a pair of large-diameter annular portions provided at both ends in the axial direction of the small-diameter cylindrical portion, and a pair of large-diameter annular portions of the small-diameter cylindrical portion. It is equipped with a coil. The first rotating body has an annular shape, and has a gap with one outer peripheral surface of a pair of large-diameter annular portions so that the inner peripheral surfaces face each other. The second rotating body has an annular shape, and has a gap with the other outer peripheral surface of the pair of large-diameter annular portions so that the inner peripheral surfaces face each other. The guide member guides at least one of the first and second rotating bodies in the axial direction. The fixed body is provided with a first permanent magnet and a second permanent magnet that is easier to magnetize than the first permanent magnet. The magnetic field generated from the coil reverses the magnetic poles of the second permanent magnet, and the magnetic fluxes of the first and second permanent magnets pass through the first and second rotating bodies in response to the magnetic pole reversal of the second permanent magnet and engage both. It is possible to switch between the engaged state of matching and the open state in which the magnetic fields of the first and second permanent magnets do not pass through the first and second rotating bodies. In this configuration, the gap widths between the outer peripheral surfaces of the pair of large-diameter ring portions and the inner peripheral surfaces of the first and second rotating bodies are formed to be equal along the circumferential direction. Further, between one outer peripheral surface of the pair of large-diameter annular portions and the inner peripheral surface of the first rotating body, and between the other of the pair of large-diameter annular portions and the inner peripheral surface of the second rotating body. Only magnetic fluxes of the same polarity pass along the circumferential direction.

Further, in the above invention, the first permanent magnet may be provided on the fixed body on the outer peripheral side of the coil so as to connect a pair of large diameter ring portions.

Further, in the above invention, the second permanent magnet is provided on a pair of large-diameter ring portions, and is relatively on the outer peripheral side and relatively on the inner peripheral side with one magnetic pole provided along the circumferential direction. It may be provided with the other magnetic pole provided along the circumferential direction.

Further, in the above invention, a row of protrusions that mesh with each other may be formed on the facing surfaces of the first rotating body and the second rotating body.

According to the present invention, the gap widths between the outer peripheral surfaces of the pair of large-diameter annular portions of the fixed body and the inner peripheral surfaces of the first and second rotating body yokes are made equal along the circumferential direction. Further, between one outer peripheral surface of the pair of large-diameter ring portions and the inner peripheral surface of the first rotating body yoke, and between the other of the pair of large-diameter ring portions and the inside of the second rotating body yoke. Only magnetic fluxes having the same polarity pass along the circumferential direction with the peripheral surface. As a result, the change in magnetic flux along the circumferential direction, that is, the rotation direction can be suppressed, and the generation of eddy current can be suppressed.

It is a partially cutaway perspective sectional view of the engaging device which concerns on 1st Embodiment. It is a partially cutaway perspective sectional view which shows another example of the engaging apparatus which concerns on 1st Embodiment. It is a graph explaining the characteristic of a permanent magnet. It is a figure which illustrates the open state of the engaging device which concerns on 1st Embodiment. It is a figure which illustrates the time of polarity reversal of the engaging device which concerns on 1st Embodiment. It is a figure which illustrates the engaging state of the engaging device which concerns on 1st Embodiment. It is a partially cutaway perspective sectional view which shows further another example of the engaging apparatus which concerns on 1st Embodiment. It is a figure which illustrates the open state and the engaging state of another example of the engaging device which concerns on 1st Embodiment. It is a partially cutaway perspective sectional view of the engaging device which concerns on 2nd Embodiment. It is a figure which illustrates the open state of the engaging device which concerns on 2nd Embodiment. It is a figure which illustrates the time of polarity reversal of the engaging device which concerns on 2nd Embodiment. It is a figure which illustrates the engaging state of the engaging device which concerns on 2nd Embodiment. It is a perspective sectional view of the engaging device which concerns on the prior art. It is a figure which illustrates the open state of the engaging device which concerns on the prior art. It is a figure which illustrates the engaging state of the engaging device which concerns on the prior art. It is a figure explaining the magnetic flux when the engaging state of the engaging device which concerns on the prior art is applied to the engagement between rotating bodies.

<First Embodiment>
FIG. 1 illustrates the engaging device 10 according to the first embodiment. The engaging device 10 includes a fixed body 12, a first rotating body 14, and a second rotating body 16. The engaging device 10 functions as, for example, a clutch device that connects the first rotating body 14 and the second rotating body 16 to transmit a driving force. From FIG. 1, the drawings show X-axis, Y-axis, and Z-axis that are orthogonal to each other. The Y-axis is an axis parallel to the rotation axis. The X-axis and Z-axis are radial axes orthogonal to the rotation axis. The X-axis and Z-axis are also orthogonal.

The fixed body 12 includes a bobbin 18, a coil 20, and variable polarity magnets 22A and 22B (second permanent magnets). The bobbin 18 is an H-shaped member viewed from the side (Z-axis direction), and has a small-diameter cylindrical portion 26 extending in the rotation axis direction (Y-axis direction) and a pair of large-diameter annular portions 24A provided at both ends thereof. It is equipped with 24B. At least a part of the bobbin 18 is made of a high magnetic permeability material, for example, a soft magnetic material such as low carbon steel.

A coil 20 is wound around the small-diameter cylindrical portion 26 of the bobbin 18. The coil 20 is connected to an external power source (not shown) via the connection wiring 28. The number of turns of the coil 20 around the small-diameter cylindrical portion 26 may be one or a plurality of turns.

The variable polarity magnets 22A and 22B form at least a part of the large-diameter ring portions 24A and 24B, respectively. For example, the entire large diameter ring portions 24A and 24B may be composed of the polarity variable magnets 22A and 22B, respectively. In this case, the small-diameter cylindrical portion 26 is formed of a high magnetic permeability material and used as a yoke. The outer peripheral surface of the variable polarity magnet 22A constitutes the outer peripheral surface of the large-diameter annular portion 24A, and the outer peripheral surface of the variable polarity magnet 22B constitutes the outer peripheral surface of the large-diameter annular portion 24B.

The polarity variable magnets 22A and 22B are configured so that only the same magnetic poles are aligned along the circumferential direction. For example, in the polarity variable magnet 22A, as shown by a broken line in FIG. 1, one magnetic pole 23A (for example, S pole) is relatively arranged on the outer peripheral side along the circumferential direction, and relatively on the inner peripheral side. The other magnetic pole 23B (for example, N pole) is arranged along the circumferential direction. By doing so, only magnetic fluxes having the same magnetism pass along the circumferential direction.

The polarity variable magnet 22B is arranged so that the magnetic poles are reversed from those of the polarity variable magnet 22A. That is, one magnetic pole 23B (for example, N pole) is relatively arranged on the outer peripheral side along the circumferential direction, and the other magnetic pole 23A (for example, S pole) is relatively arranged on the inner peripheral side along the circumferential direction. ) Is placed.

Both the polarity variable magnets 22A and 22B may have a cylindrical shape. Further, as shown in FIG. 2, a plurality of arc-shaped variable polarity magnets 22A and 22B may be assembled to form a cylindrical shape.

The variable polarity magnets 22A and 22B have a characteristic that they are easier to magnetize than the polarity fixing magnet 32 (first permanent magnet) described later. That is, it has a characteristic that the magnetic poles are more easily inverted than the polarity fixing magnet 32. FIG. 3 illustrates a magnet characteristic graph composed of a magnetic field (horizontal axis) and a magnetic flux density (vertical axis).

Generally, the operating point of a magnet is determined by the intersection of a permeance straight line (a straight line determined by the shape of a magnet or a magnetic circuit) and a demagnetization curve. For example, assuming a permeance straight line as shown in FIG. 3, the operating point of the alnico magnet (Alnico5) is point A, and that of the neodymium magnet is point B. From this graph, it can be seen that the alnico magnet can obtain only about 1/3 of the magnetic flux density of the neodymium magnet.

This leads to the fact that the alnico magnet (Almico5) is easy to magnetize but has a weak magnetic force, and the neodymium magnet (Ne-Fe-B) is difficult to magnetize but has a strong magnetic force. Based on the above, the polarity variable magnets 22A and 22B are composed of, for example, alnico magnets, and the polarity fixing magnet 32 is composed of, for example, neodymium magnets.

The first rotating body 14 includes a first rotating body yoke 30A, a second rotating body yoke 30B, and a polarity fixing magnet 32. The first rotating body 14 is a substantially ring-shaped member provided on the outer peripheral side of the fixed body 12 and on the inner peripheral side of the second rotating body 16. The first rotating body 14 can rotate along its circumferential direction (in other words, around the Y axis).

The first rotating body yoke 30A is made of a high magnetic permeability material, and is made of a soft magnetic material such as low carbon steel. The first rotating body yoke 30A has a substantially annular shape, and its inner peripheral surface is provided with a gap (interval) so as to face the outer peripheral surface of the large-diameter annular portion 24A (polarity variable magnet 22A). Further, the axial length of the first rotating body yoke 30A is formed to be substantially equal to the axial length of the large-diameter annular portion 24A (polarity variable magnet 22A).

Further, the gap width W1 between the inner peripheral surface of the first rotating body yoke 30A and the outer peripheral surface of the large-diameter annular portion 24A (polarity variable magnet 22A) is formed so as to be equal along the circumferential direction. As a result, the magnetic resistance due to the gap becomes uniform along the circumferential direction, so that the change in magnetic flux along the circumferential direction is suppressed, and as a result, the generation of eddy current is suppressed.

For example, the outer peripheral surface of the large-diameter annular portion 24A (polarity variable magnet 22A) and the inner peripheral surface of the first rotating body yoke 30A are formed so as to be concentric circles in a side view (Y-axis direction view). The first rotating body 14 maintains a gap width W1 between the first rotating body yoke 30A and the outer peripheral surface of the large-diameter annular portion 24A (polarity variable magnet 22A) by a bearing or the like (not shown).

The second rotating body yoke 30B is made of a high magnetic permeability material, and is made of a soft magnetic material such as low carbon steel. The second rotating body yoke 30B also has a substantially annular shape like the first rotating body yoke 30A, and its axial length is substantially equal to the axial length of the large-diameter annular portion 24B (polarity variable magnet 22B). .. Further, the inner peripheral surface of the second rotating body yoke 30B is provided with a gap (interval) so as to face the outer peripheral surface of the large-diameter annular portion 24B (polarity variable magnet 22B).

Further, the gap width W1 between the inner peripheral surface of the second rotating body yoke 30B and the outer peripheral surface of the large-diameter annular portion 24B (polarity variable magnet 22B) is formed to be equal along the circumferential direction. As a result, the magnetic resistance becomes uniform along the circumferential direction, so that the change in magnetic flux due to the gap along the circumferential direction is suppressed, and as a result, the generation of eddy current is suppressed.

For example, the outer peripheral surface of the large-diameter annular portion 24B (polarity variable magnet 22B) and the inner peripheral surface of the second rotating body yoke 30B are formed so as to be concentric circles in a side view (Y-axis direction view). The first rotating body 14 maintains a gap width W1 between the inner peripheral surface of the second rotating body yoke 30B and the outer peripheral surface of the large-diameter annular portion 24B (polarity variable magnet 22B) by a bearing or the like (not shown).

On the other hand, the gaps between the outer peripheral surfaces of the first and second rotating bodies 30A and 30B and the inner peripheral surfaces of the second rotating body 16 are formed so as to be different along the circumferential direction. For example, uneven portions 31A are formed on the outer peripheral surfaces of the first and second rotating body yokes 30A and 30B along the circumferential direction, and the uneven portions 31B are also formed on the inner peripheral surfaces of the second rotating body 16 along the circumferential direction. Is formed. With such a shape, the magnetic resistance between the outer peripheral surfaces of the first and second rotating body yokes 30A and 30B and the inner peripheral surface of the second rotating body 16 is different along the circumferential direction. .. As a result, the relative rotation between the first and second rotating body yokes 30A and 30B and the second rotating body 16 is hindered, and both can rotate in synchronization.

As described above, the polarity fixed magnet 32 (first permanent magnet) has a characteristic that it is difficult to magnetize as compared with the polarity variable magnets 22A and 22B. For example, the polarity fixing magnet 32 is composed of a neodymium magnet. The polarity fixing magnet 32 is provided so as to connect (connect) between the first rotating body yoke 30A and the second rotating body yoke 30B. That is, the polarity fixing magnet 32 has a function of communicating (connecting) the gap between the first rotating body yoke 30A and the second rotating body yoke 30B. The polarity fixing magnet 32 is formed, for example, in an annular shape.

The polarity fixing magnet 32 may be provided on at least one of the fixed body 12 and the first rotating body 14. Regarding this point, since the polarity fixing magnet 32 (first magnet) is provided on the first rotating body 14, there is an advantage that the number of gaps to be overcome when forming a magnetic flux loop with the second rotating body 16 is only two. Is obtained. As a comparative example, when a polar fixing magnet 32 is provided on the fixed body 12, when a magnetic flux loop with the second rotating body 16 is formed including a gap formed between the fixed body 12 and the first rotating body 14. The number of gaps to overcome is four. In this way, by providing the polar fixing magnet 32 on the first rotating body 14 having a relatively small number of gaps to be overcome, it is possible to suppress a decrease in magnetic force due to magnetic resistance when the gap is overcome.

The second rotating body 16 is a cylindrical member provided on the outer peripheral side of the first rotating body 14. The second rotating body 16 is made of a high magnetic permeability material, and is made of a soft magnetic material such as low carbon steel. The second rotating body 16 is rotatably supported around its axis (Y axis) by a bearing or the like (not shown).

4 to 6 illustrate the open state, the magnetic pole reversal, and the engaged state of the engaging device 10 according to the first embodiment. In addition, each of FIGS. 4 to 6 shows the ZZ plane of the perspective view of FIG. 1 or FIG.

FIG. 4 shows an example at the time of opening. At the time of opening, the first rotating body 14 and the second rotating body 16 are disengaged. Specifically, as shown in FIG. 4, the polar variable magnets 22A and 22B and the polar fixed magnets 32 have the same polarity (in a series state), and the magnetic fluxes of these magnets become a combined magnetic flux and are loops shown by broken lines. It passes through the path L_OFF. Specifically, the magnetic fluxes of the polar variable magnets 22A and 22B and the polar fixed magnet 32 are the polar fixed magnet 32 → the first rotating body yoke 30A → the polar variable magnet 22A → the bobbin 18 (small diameter columnar portion 26) → the polar variable magnet 22B. → Second rotating body yoke 30B → Passes through the path with the polarity fixing magnet 32.

FIG. 5 illustrates the state at the time of polarity reversal. By supplying an electric current to the coil 20 to generate a magnetic field, the polarities of the variable polarity magnets 22A and 22B are reversed. For example, from the graph of FIG. 3, a magnetic field having an intermediate value between the operating points A and B is generated in the coil 20, and the polarities of the polar variable magnets 22A and 22B are selectively inverted.

FIG. 6 illustrates the state at the time of engagement after the polarity is reversed. As shown by the broken line in this figure, the magnetic fluxes of the variable polarity magnets 22A and 22B and the magnetic fluxes of the fixed polarity magnets 32 have opposite polarities, so that two types of loop paths L_ON1 and L_ON2 are conceptually generated in parallel. To do.

That is, a loop path L_ON1 that passes through the path of the polarity fixing magnet 32 → the first rotating body yoke 30A → the second rotating body 16 → the second rotating body yoke 30B → the polarity fixing magnet 32 is formed. Further, it passes through the path of the polarity variable magnet 22A → the first rotating body yoke 30A → the second rotating body 16 → the second rotating body yoke 30B → the polarity variable magnet 22B → the bobbin 18 (small diameter cylindrical portion 26) → the polarity variable magnet 22A. Loop path L_ON2 is formed.

Since the loop paths L_ON1 and L_ON2 pass through (chain) the first rotating body 14 and the second rotating body 16, they are magnetically coupled to each other. Further, as described above, since the facing surfaces of the two are formed so that the gap width W2 changes along the circumferential direction (rotation direction), the first rotating body 14 and the second rotating body 14 and the second rotation so as to hinder the change in magnetic flux. The body 16 rotates synchronously. That is, they are engaged.

Further, since the loop paths L_ON1 and L_ON2 pass through (chain) the fixed body 12 and the first rotating body 14, they are magnetically coupled to each other. However, as described above, only magnetic fluxes having the same polarity pass along the circumferential direction on the outer peripheral surface of the large-diameter annular portion 24A (variable polarity magnet 22A) of the bobbin 18 and the inner peripheral surface of the first rotating body yoke 30A. Similarly, the outer peripheral surface of the large-diameter annular portion 24B (variable polarity magnet 22B) of the bobbin 18 and the inner peripheral surface of the second rotating body yoke 30B also have only magnetic fluxes having the same polarity along the circumferential direction (rotation direction). pass.

Further, the outer peripheral surface of the large-diameter annular portion 24A (polarity variable magnet 22A) of the bobbin 18 and the inner peripheral surface of the first rotating body yoke 30A, and the large-diameter annular portion 24B (polarity variable magnet 22B) of the bobbin 18 The gap width W1 between the outer peripheral surface of the magnet and the inner peripheral surface of the second rotating body yoke 30B is formed to be constant along the circumferential direction (rotational direction). As a result, since the magnetic flux distribution along the circumferential direction is not generated, the generation of eddy currents that cause "catch" of rotation is suppressed, and the first rotating body 14 and the second rotating body 16 can be smoothly rotated. Become.

<Modified example of the first embodiment>
In the example shown in FIG. 1, the fixed body 12 is provided with the polarity variable magnets 22A and 22B, but the present invention is not limited to this form. For example, as illustrated in FIG. 7, the first rotating body 14 may be provided with the polarity variable magnets 22A and 22B.

In the example shown in FIG. 7, the polarity variable magnet 22A is provided on the inner peripheral side of the first rotating body yoke 30A, and the polarity variable magnet 22B is provided on the inner peripheral side of the first rotating body yoke 30A. Here, for convenience, assuming that the polarity variable magnet 22A is included as a part of the first rotating body yoke 30A and the polarity variable magnet 22B is included as a part of the second rotating body yoke 30B, the first rotating body yoke is included. The gap width W1 between the inner peripheral surface of the 30A (variable polarity magnet 22A) and the outer peripheral surface of the large-diameter annular portion 24A is formed so as to be equal along the circumferential direction. Similarly, the gap width W1 between the inner peripheral surface of the second rotating body yoke 30B (polarity variable magnet 22B) and the outer peripheral surface of the large-diameter annular portion 24B is formed so as to be equal along the circumferential direction.

Further, as in the example of FIG. 1, the polarity variable magnets 22A and 22B are configured so that only the same magnetic poles are aligned along the circumferential direction. For example, in the variable polarity magnet 22A, as shown by a broken line in FIG. 7, one magnetic pole 23A (for example, S pole) is relatively arranged on the outer peripheral side along the circumferential direction, and relatively on the inner peripheral side. The other magnetic pole 23B (for example, N pole) is arranged along the circumferential direction.

The polarity variable magnet 22B is arranged so that the magnetic poles are reversed from those of the polarity variable magnet 22A. That is, one magnetic pole 23B (for example, N pole) is relatively arranged on the outer peripheral side along the circumferential direction, and the other magnetic pole 23A (for example, S pole) is relatively arranged on the inner peripheral side along the circumferential direction. ) Is placed.

The upper part of FIG. 8 shows an example when the engaging device 10 according to the embodiment of FIG. 7 is open, and the lower part of FIG. 8 shows an example when the engaging device 10 is engaged.

In the upper part of FIG. 8, the polarities of the variable polarity magnets 22A and 22B and the polarity fixing magnet 32 are aligned, and the magnetic fluxes of these magnets are in series to form a combined magnetic flux and pass through the loop path L_OFF shown by the broken line. Specifically, the magnetic fluxes of the polar variable magnets 22A and 22B and the polar fixed magnet 32 are the polar fixed magnet 32 → the first rotating body yoke 30A (polarity variable magnet 22A) → bobbin 18 → the second rotating body yoke 30B (variable polarity). Magnet 22B) → Passes through the path with the polarity fixing magnet 32.

The lower part of FIG. 8 illustrates the state of engagement after polarity reversal. As shown by the broken line in this figure, the magnetic fluxes of the variable polarity magnets 22A and 22B and the magnetic fluxes of the fixed polarity magnets 32 have opposite polarities, so that two types of loop paths L_ON1 and L_ON2 are conceptually generated in parallel. To do.

That is, a loop path L_ON1 that passes through the path of the polarity fixing magnet 32 → the first rotating body yoke 30A → the second rotating body 16 → the second rotating body yoke 30B → the polarity fixing magnet 32 is formed. Further, the first rotating body yoke 30A (polarity variable magnet 22A) → the second rotating body 16 → the second rotating body yoke 30B (polarity variable magnet 22B) → bobbin 18 → the first rotating body yoke 30A (polarity variable magnet 22A). The loop path L_ON2 that passes through the path of the above is formed.

Since the loop paths L_ON1 and L_ON2 pass through (chain) the first rotating body 14 and the second rotating body 16, they are magnetically coupled to each other. Further, as described above, since the facing surfaces of the two are formed so that the gap width W2 changes along the circumferential direction (rotation direction), the first rotating body 14 and the second rotating body 14 and the second rotation so as to hinder the change in magnetic flux. The body 16 rotates synchronously. That is, they are engaged.

On the other hand, since the loop paths L_ON1 and L_ON2 pass through (chain) the fixed body 12 and the first rotating body 14, they are magnetically coupled. However, as described above, only magnetic fluxes having the same polarity pass along the circumferential direction on the outer peripheral surface of the large-diameter annular portion 24A of the bobbin 18 and the inner peripheral surface of the first rotating body yoke 30A (polarity variable magnet 22A). Similarly, the outer peripheral surface of the large-diameter annular portion 24B of the bobbin 18 and the inner peripheral surface of the second rotating body yoke 30B (polarity variable magnet 22B) also have only magnetic fluxes having the same polarity along the circumferential direction (rotation direction). pass.

Further, the outer peripheral surface of the large-diameter annular portion 24A of the bobbin 18, the inner peripheral surface of the first rotating body yoke 30A (polarity variable magnet 22A), and the outer peripheral surface of the large-diameter annular portion 24B of the bobbin 18 and the second. The gap width W1 of the rotating body yoke 30B (variable polarity magnet 22B) with the inner peripheral surface is formed so as to be constant along the circumferential direction (rotation direction). As a result, since the magnetic flux distribution along the circumferential direction is not generated, the generation of eddy currents that cause "catch" of rotation is suppressed, and the first rotating body 14 and the second rotating body 16 can be smoothly rotated. Become.

<Second Embodiment>
FIG. 9 illustrates the engaging device 50 according to the second embodiment. The engaging device 50 functions as an actuator device capable of relatively moving the first rotating body 52 and the second rotating body 54 in the axial direction (Y-axis direction). The engaging device 50 includes a fixed body 56, a first rotating body 52, a second rotating body 54, and a guide member 58.

The fixed body 56 includes a bobbin 60, a coil 62, a polarity fixing magnet 64 (first permanent magnet), and polarity variable magnets 66A and 66B (second permanent magnet). The bobbin 60 includes a small-diameter cylindrical portion 68 and large-diameter annular portions 70A and 70B at both ends in the axial direction (Y-axis direction) thereof. Further, a polarity variable magnet 66A is provided as a part of the large diameter ring portion 70A, and a polarity variable magnet 66B is provided as a part of the large diameter ring portion 70B. The portion of the bobbin 60 other than the variable polarity magnets 66A and 66B functions as a yoke. That is, the portion is made of a high magnetic permeability material, and is made of a soft magnetic material such as low carbon steel.

The variable polarity magnets 66A and 66B have a characteristic that they are easier to magnetize than the fixed polarity magnets 64. As will be described later, the polarities of the variable polarity magnets 66A and 66B are reversed by the magnetic field generated from the coil 62. The variable polarity magnets 66A and 66B are composed of, for example, alnico magnets.

Further, the polarity variable magnets 66A and 66B are configured so that only the same magnetic poles are aligned along the circumferential direction. For example, in the variable polarity magnet 66A, as shown by the broken line in FIG. 9, one magnetic pole 67A (for example, S pole) is relatively arranged on the outer peripheral side along the circumferential direction, and relatively on the inner peripheral side. The other magnetic pole 67B (for example, N pole) is arranged along the circumferential direction. With this configuration, only magnetic fluxes having the same polarity pass along the circumferential direction on the outer peripheral surface of the large-diameter annular portion 70A of the bobbin 60 and the inner peripheral surface of the first rotating body 52.

The polarity variable magnet 66B is arranged so that the magnetic poles are reversed from those of the polarity variable magnet 66A. That is, one magnetic pole 67B (for example, N pole) is relatively arranged on the outer peripheral side along the circumferential direction, and the other magnetic pole 67A (for example, S pole) is relatively arranged on the inner peripheral side along the circumferential direction. ) Is placed. With this configuration, only magnetic fluxes having the same polarity pass along the circumferential direction (rotational direction) on the outer peripheral surface of the large-diameter annular portion 70B of the bobbin 60 and the inner peripheral surface of the second rotating body 54.

The coil 62 is wound around the small-diameter cylindrical portion 68 of the bobbin 60. The coil 62 is connected to an external power source (not shown) via the connection wiring 72. The number of turns of the coil 62 around the small-diameter cylindrical portion 68 may be one or a plurality of turns.

The polarity fixing magnet 64 is provided on the outer peripheral side of the coil 62, for example. For example, the polarity fixing magnet 64 is provided so as to connect (connect) the large-diameter ring portion 70A and the large-diameter ring portion 70B in the axial direction. That is, the polarity fixing magnet 64 has a function of connecting (connecting) the gap between the large diameter ring portions 70A and 70B. The polarity fixing magnet 64 is formed, for example, in an annular shape. The polarity fixing magnet 64 is composed of, for example, a neodymium magnet.

The first rotating body 52 is a substantially annular member coaxial (Y-axis) with the bobbin 60. The inner peripheral surface thereof is provided with a gap (via) and faces the outer peripheral surface of the large-diameter annular portion 70A of the fixed body 56. The gap width W1 between the inner peripheral surface of the first rotating body 52 and the outer peripheral surface of the large-diameter annular portion 70A is configured to be constant (equal) along the circumferential direction. As a result, the magnetic resistance becomes uniform along the circumferential direction, so that the change in magnetic flux due to the gap along the circumferential direction is suppressed, and as a result, the generation of eddy current is suppressed.

For example, the outer peripheral surface of the large-diameter annular portion 70A and the inner peripheral surface of the first rotating body 52 are formed so as to be concentric circles in a side view (Y-axis direction view). The gap width W1 between the inner peripheral surface of the first rotating body 52 and the outer peripheral surface of the large-diameter annular portion 70A is maintained by a bearing or the like (not shown).

The first rotating body 52 can rotate around an axis (around the Y axis) and can move linearly along the axial direction (Y axis direction). For example, the first rotating body 52 moves linearly in the axial direction while being guided by the guide member 58. The first rotating body 52 is urged by the return spring 76 to a side separated from the second rotating body 54. As will be described later, when the engaging device 50 is engaged, the first rotating body 52 moves linearly toward the second rotating body 54 so as to resist this urging force.

Further, on the side surface 73 of the first rotating body 52 facing the second rotating body 54, a protrusion row 74A provided with a plurality of protrusions (dogs) along the circumferential direction is provided. The protrusion width in the protrusion row 74A is the same as the pitch (interval) of the protrusion row 74B provided on the side surface (opposing surface) of the second rotating body 54, and the pitch in the protrusion row 74A is the protrusion width of the protrusion row 74B. It is preferable that it is the same as. By providing such a configuration, when the first rotating body 52 and the second rotating body 54 are close to each other along the axial direction, the projection rows 74A and 74B mesh with each other, and synchronous rotation driving becomes possible.

The guide member 58 is a substantially cylindrical member provided so as to cover the outer peripheral surface of the first rotating body 52. The inner peripheral surface of the guide member 58 and the outer peripheral surface of the first rotating body 52 can be moved relative to each other by, for example, sliding. That is, the movement of the first rotating body 52 is guided in the axial direction by the guide member 58. One end of the return spring 76 is connected to the flange 78 of the guide member 58. A plurality of return springs 76 may be provided in the circumferential direction. Further, the guide member 58 can rotate in synchronization with the first rotating body 52.

The second rotating body 54 is a substantially cylindrical member coaxial (Y-axis) with the bobbin 60. The inner peripheral surface thereof is provided with a gap and faces the outer peripheral surface of the large-diameter annular portion 70B of the fixed body 56. The gap width W1 between the inner peripheral surface of the second rotating body 54 and the outer peripheral surface of the large-diameter annular portion 70B is configured to be constant (equal) along the circumferential direction. As a result, the magnetic resistance becomes uniform along the circumferential direction, so that the change in magnetic flux due to the gap along the circumferential direction is suppressed, and as a result, the generation of eddy current is suppressed.

For example, the outer peripheral surface of the large-diameter annular portion 70B and the inner peripheral surface of the second rotating body 54 are formed so as to be concentric circles in a side view (Y-axis direction view). The gap width W1 between the inner peripheral surface of the second rotating body 54 and the outer peripheral surface of the large-diameter annular portion 70B is maintained by a bearing or the like (not shown).

The second rotating body 54 is adjacent to the first rotating body 52 in the axial direction (Y-axis direction). Further, the second rotating body 54 is rotatable around an axis (around the Y axis). On the other hand, unlike the first rotating body 52, the second rotating body 54 is restricted from linear movement in the axial direction.

Not limited to this form, the second rotating body 54 may also be provided with a guide member 58 so that it can move linearly in the axial direction. Further, the guide member 58 may be provided only on the second rotating body 54 to regulate the linear motion of the first rotating body 52.

On the side surface (opposing surface) of the second rotating body 54 facing the first rotating body 52, a protrusion row 74B provided with a plurality of protrusions (dogs) along the circumferential direction is provided. As described above, it is preferable that the protrusion width in the protrusion row 74B is the same as the pitch (interval) of the protrusion row 74A, and the pitch in the protrusion row 74B is the same as the protrusion width of the protrusion row 74A.

10 to 12 illustrate the open state, the magnetic pole reversal, and the engaged state of the engaging device 50 according to the second embodiment. It should be noted that FIGS. 10 to 12 all show the ZZ plane of the perspective view of FIG.

FIG. 10 shows an example at the time of opening. At the time of opening, the first rotating body 52 and the second rotating body 54 are disengaged.

As shown in FIG. 10, the polar variable magnets 66A and 66B and the polarity fixed magnet 64 have the same polarity, and the magnetic fluxes of these magnets form a combined magnetic flux in series and pass through the loop path L_OFF shown by the broken line. Specifically, the magnetic fluxes of the polar variable magnets 66A and 66B and the polar fixed magnet 64 are as follows: polar fixed magnet 64 → large diameter ring portion 70A → polar variable magnet 66A → small diameter cylindrical portion 68 → polar variable magnet 66B → large diameter circle. It passes through the path from the ring portion 70B to the polarity fixing magnet 64.

As described above, the magnetic fluxes of the polar variable magnets 66A and 66B and the polar fixed magnet 64 do not pass (interlink) with the first rotating body 52 and the second rotating body 54. Therefore, the first rotating body 52 is separated from the second rotating body 54 in the axial direction (Y-axis direction) by the return spring 76 without attracting the two due to the magnetic force.

FIG. 11 illustrates the state at the time of polarity reversal. By supplying a current to the coil 62 to generate a magnetic field, the polarities of the variable polarity magnets 66A and 66B are reversed. For example, from the graph of FIG. 3, a magnetic field having an intermediate value between the operating points A and B is generated in the coil 62 to selectively reverse the polarities of the polar variable magnets 66A and 66B.

FIG. 12 illustrates the state of engagement after polarity reversal. As shown by the broken line in this figure, the magnetic fluxes of the variable polarity magnets 66A and 66B and the magnetic fluxes of the fixed polarity magnets 64 have opposite polarities, so that two types of loop paths L_ON1 and L_ON2 are conceptually generated in parallel. To do.

That is, a loop path L_ON1 that passes through the path of the polarity fixing magnet 64 → the large diameter ring portion 70A → the first rotating body 52 → the second rotating body 54 → the large diameter ring portion 70B → the polarity fixing magnet 64 is formed. .. Further, the path from the variable polarity magnet 66A → the large diameter annular portion 70A → the first rotating body 52 → the second rotating body 54 → the large diameter annular portion 70B → the variable polarity magnet 66B → the small diameter cylindrical portion 68 → the variable polarity magnet 66A. A loop path L_ON2 passing through is formed.

Since the loop paths L_ON1 and L_ON2 pass through (chain) the first rotating body 52 and the second rotating body 54, they are magnetically coupled and attract each other. At this time, the first rotating body 52 moves linearly in the axial direction (Y-axis direction) against the elastic force of the return spring 76 and approaches the second rotating body 54. Further, the protrusion row 74A of the first rotating body 52 and the protrusion row 74B of the second rotating body 54 mesh with each other, and both rotate and move in synchronization with each other.

At this time, the fixed body 56, the first rotating body 52, and the second rotating body 54 are magnetically coupled by the loop paths L_ON1 and L_ON2. However, as described above, only magnetic fluxes having the same polarity pass along the circumferential direction on the outer peripheral surface of the large-diameter annular portion 70A of the bobbin 60 and the inner peripheral surface of the first rotating body 52, and similarly, the bobbin 60 Only magnetic fluxes having the same polarity pass along the circumferential direction (rotational direction) of the outer peripheral surface of the large-diameter annular portion 70B and the inner peripheral surface of the second rotating body 54. Further, the outer peripheral surface of the large-diameter annular portion 70A of the bobbin 60 and the inner peripheral surface of the first rotating body 52, and the outer peripheral surface of the large-diameter annular portion 70B of the bobbin 60 and the inner peripheral surface of the second rotating body 54. The gap width W1 with and is formed to be constant along the circumferential direction (rotational direction). As a result, since the magnetic flux distribution along the circumferential direction is not generated, the generation of eddy currents that cause "catch" of rotation is suppressed, and the first rotating body 52 and the second rotating body 54 can be smoothly rotated. Become.

10,50 Engagement device, 12,56 fixed body, 14,52 first rotating body, 16,54 second rotating body, 18,60 bobbin, 20,62 coil, 22A, 22B, 66A, 66B polarity variable magnet, 24A, 24B, 70A, 70B Large diameter ring part, 26,68 small diameter column part, 30A, 30B rotating body yoke, 32,64 polar fixing magnet, 74A, 74B protrusion row.

Claims (8)

It was wound between a bobbin having a small-diameter cylindrical portion and a pair of large-diameter annular portions provided at both ends in the axial direction of the small-diameter cylindrical portion, and the pair of large-diameter annular portions of the small-diameter cylindrical portion. A fixed body with a coil,
A gap is provided between the outer peripheral surface of one of the pair of large-diameter annular portions and the ring-shaped first rotating body yoke whose inner peripheral surfaces face each other, and the other of the pair of large-diameter annular portions. A first rotating body including a ring-shaped second rotating body yoke whose inner peripheral surfaces face each other, and
A second rotating body having an inner peripheral surface formed so that the gap width between the first and second rotating body yokes and the outer peripheral surface is different along the circumferential direction.
With
At least one of the fixed body and the first rotating body is provided with a first permanent magnet and a second permanent magnet that is easier to magnetize than the first permanent magnet.
The magnetic field generated from the coil reverses the magnetic poles of the second permanent magnet, and the magnetic fluxes of the first and second permanent magnets pass through the second rotating body in response to the magnetic pole reversal of the second permanent magnet. It is possible to switch between the state and the open state in which the magnetic fields of the first and second permanent magnets do not pass through the second rotating body.
It ’s an engaging device,
The gap widths between the outer peripheral surfaces of the pair of large-diameter ring portions and the inner peripheral surfaces of the first and second rotating body yokes are formed to be equal along the circumferential direction.
Between one outer peripheral surface of the pair of large-diameter ring portions and the inner peripheral surface of the first rotating body yoke, and between the other of the pair of large-diameter ring portions and the inner circumference of the second rotating body yoke. Only magnetic fluxes of the same polarity pass along the circumferential direction between the surfaces.
Engagement device. The engaging device according to claim 1.
The first permanent magnet is an engaging device provided on the first rotating body so as to connect the first rotating body yoke and the second rotating body yoke. The engaging device according to claim 1 or 2.
The second permanent magnet is provided on the pair of large-diameter ring portions, and has one magnetic pole that is relatively on the outer peripheral side and is provided along the circumferential direction, and is relatively on the inner peripheral side and is circumferential. Engagement device with the other magnetic pole provided along the direction. The engaging device according to claim 1 or 2.
The second permanent magnet is provided on the first and second rotating body yokes, and is relatively on the outer peripheral side and relatively on the inner peripheral side with one magnetic pole provided along the circumferential direction. An engaging device including the other magnetic pole provided along the circumferential direction. It was wound between a bobbin having a small-diameter cylindrical portion and a pair of large-diameter annular portions provided at both ends in the axial direction of the small-diameter cylindrical portion, and the pair of large-diameter annular portions of the small-diameter cylindrical portion. A fixed body with a coil,
A ring-shaped first rotating body having a gap with one outer peripheral surface of the pair of large-diameter annular portions and facing the inner peripheral surfaces.
A ring-shaped second rotating body having a gap with the other outer peripheral surface of the pair of large-diameter annular portions and facing the inner peripheral surfaces.
A guide member that guides at least one of the first and second rotating bodies in the axial direction, and
With
The fixed body is provided with a first permanent magnet and a second permanent magnet that is easier to magnetize than the first permanent magnet.
The magnetic field generated from the coil reverses the magnetic poles of the second permanent magnet, and the magnetic fluxes of the first and second permanent magnets pass through the first and second rotating bodies in response to the magnetic pole reversal of the second permanent magnet. It is possible to switch between an engaged state in which the two are engaged with each other and an open state in which the magnetic fluxes of the first and second permanent magnets do not pass through the first and second rotating bodies.
It ’s an engaging device,
The gap widths between the outer peripheral surfaces of the pair of large-diameter ring portions and the inner peripheral surfaces of the first and second rotating bodies are formed to be equal along the circumferential direction.
Between one outer peripheral surface of the pair of large-diameter ring portions and the inner peripheral surface of the first rotating body, and between the other of the pair of large-diameter ring portions and the inner peripheral surface of the second rotating body. Only magnetic fluxes of the same polarity pass along the circumferential direction between them.
Engagement device. The engaging device according to claim 5.
The first permanent magnet is an engaging device provided on the fixed body on the outer peripheral side of the coil so as to connect the pair of large-diameter ring portions. The engaging device according to claim 5 or 6.
The second permanent magnet is provided on the pair of large-diameter ring portions, and has one magnetic pole that is relatively on the outer peripheral side and is provided along the circumferential direction, and is relatively on the inner peripheral side and is circumferential. Engagement device with the other magnetic pole provided along the direction. The engaging device according to claim 5 or 6.
An engaging device in which a row of protrusions that mesh with each other is formed on the facing surfaces of the first rotating body and the second rotating body.