JPS6350818Y2 - - Google Patents

Description

[Detailed explanation of the invention] This invention attracts the armature using magnetic force.
This relates to a magnetic drive device for detaching.

Generally, in a device that attracts and detaches an armature using magnetic force, a holding force is required when the armature is attracted. For this purpose, it is necessary that the armature and the suction surface of the iron core or the like to which the armature is suctioned are brought into close contact with each other.

However, for example, in the case of a configuration in which the core is fixed to the board and the armature is rotatably supported, variations may occur in the length of the core, the perpendicularity of the end face, or the relative position between the core and the armature due to processing or assembly. There is a problem in that the armature does not come into close contact with the adsorption surface of the iron core, resulting in a decrease in holding force.

An object of the present invention is to provide a magnetic drive device that improves holding force by bringing the adhesion surfaces of an armature and a member that adsorbs it into close contact even when there are variations in component accuracy.

Therefore, in the present invention, an adsorption member constituting a magnetic circuit is disposed on the substrate, the armature that is adsorbed to and removed from the adsorption member is rotatably supported by the support member, and the end face of the adsorption member is attached to the substrate. and a holding part that holds the support member movably within a plane perpendicular to the rotation plane of the armature, and after adjusting the position of the support member with the armature in close contact with the end surface of the suction member. The above objective is achieved by fixing it to the holding part.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example in which the magnetic drive device of this embodiment is used as a brake mechanism of a small portable video recorder. In the figure, a magnetic drive device 11 is installed between a pair of flywheels 1 and 2.

As shown in FIG. 2, the magnetic drive device 11 includes a substrate 12, a yoke 14 as a support member with a permanent magnet 13 interposed therebetween, a pair of levers 15 and 16 as an armature, and a spring 17.
and a coil device 19 that houses an iron core 18 as an adsorption member therein. here,
The permanent magnet 13, the yoke 14, and the pair of levers 1
5 and 16 and the iron core 18 constitute a magnetic circuit 20.

The substrate 12 has two parallel to each other on its rear side.
The holding plates 21 and 22, which serve as holding parts for the sheets, each have a guide plate 23 cut and raised on the front edge, and
Rectangular locking holes 2 on both sides of the notch hole 24 in the center
5 and 26 are respectively provided with mounting portions 28 and 29 having mounting holes 27 on both side edges. The guide plate 23 is provided with guide pieces 30 and 31 extending outward on both sides of the top, respectively, and a notch 32 at the center of the top.

The yoke 14 includes two yoke members 33 made of a magnetic material, which are held between the holding plates 21 and 22 of the substrate 12 while holding the permanent magnet 13 between them.
It consists of 34. two yoke members 3
Opposite ends 35 and 36 of 3 and 34 are slightly bent in a direction to sandwich both side surfaces of the permanent magnet 13, and then protrude toward both sides. each end 35,
Rectangular engaging protrusions 37 and 38 are formed at the tips of 36.

Each of the levers 15 and 16 has strip plates 39 and 40 whose tips are bent slightly inward by a magnetic material.
Protrusions 41 and 42 that lock the ends of the spring 17 at the rear end, and rectangular engagement holes that are engaged with the engagement protrusions 37 and 38 of the yoke members 33 and 34 slightly forward of the protrusions 41 and 42 that engage the ends of the spring 17. 43 and 44 have insertion holes 45 and 46 formed at their tips, respectively, through which the guide pieces 30 and 31 of the substrate 12 are inserted, and
Pressing members 47 and 48 made of rubber or the like are attached to the outer surfaces of the tip portions to press the outer peripheral surfaces of the flywheels 1 and 2. The engagement holes 43, 44 have a height dimension that is approximately the same as the height of the engagement protrusions 37, 38, and a width dimension that is approximately the same as the height of the engagement protrusions 37, 38.
The size is slightly larger than the thickness of the . Therefore, due to the clearance between the widthwise dimension of the engagement holes 43 and 44 and the thickness direction dimension of the engagement protrusions 37 and 38, the levers 15 and 16 are
It can be rotated by a predetermined angle using fulcrums 7 and 38.

The coil device 19 includes a bobbin 49 and a coil 50 wound around the outer periphery of the bobbin 49. The bobbin 49 has the iron core 1 inside.
A collar 52 is integrally molded at both ends of a rectangular tube 51 that houses the coil 50 and around which the coil 50 is wound.
A protrusion piece 53 is formed to be fitted into the protrusion piece 53. Further, the coil 50 is configured to be energized with a current in the opposite direction by switching the power source.

Next, the operation of this embodiment will be explained.

First, the method of assembling the magnetic force drive device 11 is to store the iron core 18 in a bobbin 49 around which a coil 50 is wound, and to attach the protruding piece 53 of the bobbin 49 to the substrate 12.
Insert it into the locking holes 25, 26 of and fix it. Also,
Permanent magnet 13 is placed between two yoke members 33 and 34.
is held between the holding plates 21 and 22 of the substrate 12. At this stage, the two yoke members 3
3 and 34 are only sandwiched between the retaining plates 21 and 22, so that they can move laterally, that is, in the longitudinal direction of the iron core 18 and in the vertical direction, and the retaining plates 21 and 2
It is in a state where it can rotate in a state parallel to 2. Subsequently, the engaging protrusions 37 and 38 of the yoke members 33 and 34
The engagement holes 43 and 44 of the levers 15 and 16 are engaged with the levers 15 and 16, and the guide pieces 30 and 31 of the base plate 12 are inserted through the insertion holes 45 and 46 of the levers 15 and 16, respectively.

Here, the pair of levers 15 and 16 are pressed toward the end surface of the iron core 18, and the levers 15 and 16 are brought into close contact with the end surface of the iron core 18. The yoke member 3 is inserted into the engagement holes 43 and 44 of the levers 15 and 16 in this state.
The lateral positions of the yoke members 33 and 34 are adjusted so that the engagement protrusions 37 and 38 of 3 and 34 are properly engaged.
Adjust the vertical position and rotation angle. For example, if the length of the iron core 18 is different from the specified size, the horizontal positions of the levers 15 and 16 are shifted, so the adjustment is made by sliding the yoke members 33 and 34 in the horizontal direction. Furthermore, if the positions where the levers 15 and 16 abut against the end surface of the iron core 18 are shifted in the vertical direction, each yoke member 33 and 3
Slide 4 up and down to adjust. Furthermore,
If the end face of the iron core 18 is not perpendicular to its longitudinal direction, adjustment is made by adjusting the lateral position and rotation angle of each yoke member 33, 34. That is, if the end face of the iron core 18 is inclined in the front-back direction as shown in FIG. If so, the yoke member 33,
All you have to do is turn 34. If the tilt is in a direction other than the front-rear direction or the up-down direction, both operations are performed together.

After this adjustment, the two yoke members 33 and 34 and the permanent magnet 13 are integrated, and the holding plate 21 of the substrate 12,
It is integrally fixed to 22. Incidentally, as the fixing means, suitable means such as adhesion, brazing, screwing, etc. can be used. After this, a pair of levers 1
The spring 1 is inserted between the protrusions 41 and 42 of 5 and 16.
7 is tensioned, and the tips of the pair of levers 15, 16 are urged in a direction away from each other. Here, due to the tensile force of the spring 17, the pair of levers 15,
The moment when the ends of the levers 16 are urged away from each other is M ₁ , and the pair of levers 15 and 16
8, when the coil 50 is not energized, the moment that the pair of levers 15, 16 receives in the direction in which they are attracted to the iron core 18 is M ₂ ,
In a state where the pair of levers 15 and 16 are attracted to the iron core 18, when a current is applied to the coil 50 in a direction that cancels or reduces the magnetic force of the magnetic circuit 20, the pair of levers 15 and 16 are attracted to the iron core 18. The moment received in the direction is M ₀ , and the pair of levers 1
5 and 16 are separated from the iron core 18, when a current is passed through the coil 50 in the direction of increasing the magnetic force of the magnetic circuit 20, the pair of levers 15 and 16 move away from the iron core 18.
The tensile force of the spring 17 is set in advance so as to satisfy the following conditions: M ₀ <M ₁ <M ₃ <M ₂ , where M ₃ is the moment received in the direction in which the spring 17 is attracted.

Now, in the magnetic drive device 11 assembled in this way, when no current is flowing through the coil 50, the pair of levers 15 and 16 are moved against the end face of the iron core 18 by the magnetic force of the permanent magnet 13 of the magnetic circuit 20. It is held in an adsorbed state. In this state, when a current is applied to the coil 50 in a direction that cancels or reduces the magnetic force of the magnetic circuit 20, the magnetic circuit 20
As a result of the zero magnetic force being canceled or reduced, the pair of levers 15 and 16 are rotated away from each other by the tensile force of the spring 17. Therefore, the pressing members 47 and 48 of each lever 15 and 16 press the outer peripheral surfaces of the flywheels 1 and 2, and the flywheels 1 and 2 are kept stationary. At this time, since a magnetic gap is generated between the pair of levers 15, 16 and the iron core 18, even if the current in the coil 50 is cut off, the pair of levers 15, 16 are held by the magnetic force of the permanent magnet 13 alone. It will not be attracted to the iron core 18. Therefore, since the pair of levers 15, 16 are held apart from each other, the flywheels 1, 2 are kept stationary.

Therefore, when it is desired to release the static state of the flywheels 1 and 2, a current is applied to the coil 50 in a direction that increases the magnetic force of the magnetic circuit 20. Then, the magnetic force of the magnetic circuit increases, and the moment that urges the pair of levers 15 and 16 in the direction of adsorption due to the increased magnetic force is stronger than the moment that urges the pair of levers 15 and 16 in the direction of separating them from each other due to the force of the spring 17. In order to overcome the moment urging the
6 is attracted towards the iron core 18. Therefore, the pressing members 47, 48 of the levers 15, 16 are separated from the outer peripheral surfaces of the flywheels 1, 2, and the flywheels 1, 2 become rotatable. At this time, even if the current of the coil 50 is cut off, the pair of levers 15,
Since the flywheels 16 are attracted to the iron core 18 by the magnetic force of the permanent magnet 13, the flywheels 1 and 2 are maintained in a rotatable state.

Therefore, according to this embodiment, the permanent magnet 1 is attached to the substrate 12 fixed between the flywheels 1 and 2.
A pair of levers 15 and 16, which are urged in a direction away from each other by a spring 17, are rotatably supported at the ends of the yoke members 34 and 35, which hold the yoke members 34 and 35 between them. Since the iron core 18 around which the coil 50 is wound is placed between the pair of levers 15 and 16, when no current is applied to the coil 50, the pair of levers 15 and 16 are moved around the iron core by the magnetic force of the permanent magnet 13. 18 and when a current is applied to the coil 50 in a direction that cancels or reduces the magnetic force of the magnetic circuit 20, the pair of levers 15 and 16 move away from each other due to the tensile force of the spring 17. When the coil 50 is rotated and a current is applied to the coil 50 in a direction that increases the magnetic force of the magnetic circuit 20, the pair of levers 15 and 16 that have been rotated away from each other resist the tensile force of the spring 17 and move toward each other. Since it is attracted to the iron core 18, the pair of levers 15 and 16 can be operated simultaneously in opposite directions. Therefore, it is possible to hold the two flywheels 1 and 2 in a stationary or rotatable state at the same time using only one excitation drive device 11, so the size of the video recorder can be reduced compared to a conventional video recorder using a solenoid. It is measured. Moreover, when the coil 50 is temporarily energized, the pair of levers 15 and 16 are rotated in opposite directions, and then the spring 17 or the permanent magnet 1
3, the state is maintained, thereby saving power.

Further, between the holding plates 21 and 22 of the substrate 12, the yoke members 33 and 34 holding the permanent magnet 13 are movable laterally, that is, in the longitudinal direction of the iron core 18 and in the vertical direction. The yoke members 33 and 34 are engaged with the engagement holes 43 and 44 of the pair of levers 15 and 16 in a state in which the pair of levers 15 and 16 are held in a parallel state and rotatably held in close contact with the end face of the iron core 18. After adjusting the horizontal direction, vertical direction, and rotation angle of the yoke members 33 and 34 so that the mating protrusions 37 and 38 properly engage, the yoke members 33 and 34 and the permanent magnet 13 are attached to the holding plate 2.
Since the levers 15 and 16 are fixed integrally between the levers 15 and 22, when the pair of levers 15 and 16 are attracted to the iron core 18, the pair of levers 15 and 16 are attached to the end face of the iron core 18.
Since the levers 16 are in close contact with each other, the pair of levers 15 and 16
It is possible to improve the holding force when the iron core 18 is attracted to the iron core 18. In particular, even if there are variations in the length of the core 18, the perpendicularity of the end faces, and the accuracy of other parts, the pair of levers 15 and 16 can be brought into close contact with the end faces of the core 18 by the above-described adjustment.
Moreover, even when the yoke members 33, 34 are adjusted, since the yoke members 33, 34 and the permanent magnet 13 are always in close contact with each other, no magnetic gap occurs between them.

In addition, the yoke members 33 and 34 and the pair of levers 1
5 and 16, the yoke members 33 and 34 are formed with rectangular engagement protrusions 37 and 38, and the pair of levers 15 and 16 are formed with rectangular engagement holes 43 and 44, so that, for example, It is easier to process than a method in which the two are rotatably connected using a pin or the like. Moreover, since the pair of levers 15, 16 can be freely rotated by a predetermined angle due to the clearance between the engaging protrusions 37, 38 and the engaging holes 43, 44, the pair of levers 15, 16 can be rotated by a predetermined angle. When the levers 15 and 16 are rotated away from each other by a tensile force, the angle of rotation is determined by the clearance, so a stopper or the like is provided to restrict the angle of rotation of the pair of levers 15 and 16 in that direction. There's no need.

By the way, in the above embodiment, the following phenomenon may occur. Now, the direction of the magnetic flux of the magnetic circuit 20 is set to the yoke member 33, the lever 15, and the iron core 1.
8, lever 16, yoke member 34, permanent magnet 13
If the direction is , the yoke member 34 is close to the iron core 18, so it is possible that magnetic flux leaks from the iron core 18 to the yoke member 34 without passing through the lever 16. Then, even if there is a strong attraction force on the lever 15 side, the magnetic flux decreases on the lever 16 side, resulting in a decrease in the attraction force as a whole.

Therefore, as a countermeasure for this point, it is sufficient to lower the magnetic resistance of the magnetic path near the iron core 18 side. Specifically, the yoke member 34 and the lever 16 are made of a material with lower magnetic resistance than the lever 15 and the yoke member 33, or the lever 1
6 and the yoke member 34, and the cross-sectional area ratio with respect to the lever 15 and the yoke member 33 is set to 1 or more. Note that even in the case of FIG. 5, there is leakage magnetic flux, but since the magnetic flux passing through the auxiliary yoke 60 increases, the attraction force increases as a whole. In addition, although there are still problems with assembly, the yoke member 33,
34 and the permanent magnet 13 are rotated 90 degrees to form the same magnetic path, the above problem can also be solved.

In addition, in implementation, only one of the levers 15 and 16 may be actuated. for example,
When only the lever 15 is to be attracted to and removed from the iron core 18, the yoke member 34 and the lever 16 are fixed to the substrate 12 in advance. Therefore, the yoke member 33
is movably held between two holding plates 21 and 22.

In addition to the magnetic circuit 20 described in the above embodiments, the magnetic circuit 20 may be one shown in FIGS. 6 and 7, for example. In the one shown in FIG. 6, a permanent magnet 13B is integrally interposed in the middle of an iron core 18A. In this case, two yoke members 33,
34 are the retaining plates 2 in a mutually overlapping state.
It is held movably between 1 and 22. In addition, the permanent magnets 13C, 13 shown in FIG.
D is integrally attached to both end surfaces of the iron core 18 or to a pair of levers 15 and 16 facing both end surfaces of the iron core 18. Also in this case, the two yoke members 33 and 34 are the same as in FIG. 7. others,
As an aspect of the magnetic circuit 20, iron cores 18, 18A
Various types of magnets, such as those in which permanent magnets are arranged instead of the magnets, are conceivable.

In addition to the coil device 19 described in the above embodiments, the coil device 19 may be one shown in FIGS. 8 to 10, for example. In the coil 50A shown in FIG. 8, a coil 50A is wound in two layers, and an intermediate tap is pulled out from the middle of the coil 50A, and the intermediate tap is used as a common terminal so that current can be passed in the opposite direction. Therefore, in this case, there is an advantage that the power supply can be easily switched. Further, in the one shown in FIG. 9, a partition flange 52A is provided in the center of the hobbin 49, and a coil 50B, 50C are wound in the same direction, and current is applied to the coils 50B and 50C in different directions. Therefore, in this case, it is easy to switch the power supply, but there is a drawback that the coil length is approximately half of the total length of the bobbin. Furthermore, what is shown in FIG. 10 includes two coils 50.
The coils 50E and 50D are wound in two layers in opposite directions, and current is applied to the coils 50E and 50D in the same direction. Therefore, in this case, there is an advantage that the drawback shown in FIG. 9 is eliminated.

Further, yoke members 33, 34 and each lever 15,
The connecting portion with the lever 16 may have a structure in which the levers 15 and 16 are rotatably supported by an ordinary hinge. At that time, when each lever 15, 16 is rotated in a direction away from each other, each lever 15, 16
A stopper may be provided on the substrate 12 to restrict the movement.

Note that the application example of the magnetic drive device of the present invention is not limited to the video tape recorder described in the above embodiment.

As described above, according to the present invention, even if there are variations in component accuracy, the suction surfaces of the armature and the member that suctions it in the assembled state are in close contact with each other, thereby improving the holding force when the armature is suctioned. It is possible to provide a magnetic drive device that obtains the desired results.

[Brief explanation of the drawing]

Fig. 1 is a plan view of an embodiment of the magnetic drive device of the present invention applied to a brake mechanism of a video tape recorder, Fig. 2 is an exploded perspective view of the magnetic drive device, and Fig. 3 is an assembly adjustment of each part. Plan of Time, No. 4
The figure is a sectional view showing a part of each part during assembly and adjustment.
The figure is an explanatory diagram showing an example of eliminating magnetic flux leakage in a magnetic circuit, Figures 6 and 7 are explanatory diagrams each showing a modified example of the magnetic circuit, and Figures 8 to 10 are each a diagram of a coil device. It is a sectional view showing a modification. 12... Board, 15, 16... Lever as armature, 18, 18A... Iron core as adsorption member, 20... Magnetic circuit, 21, 22... Holding plate as holding part, 33, 34... Support Yoke member as a member.

Claims (1)

[Claims for Utility Model Registration] (1) A substrate, an adsorption member disposed on the substrate constituting a magnetic circuit, an armature that is adsorbed to and removed from the end face of the adsorption member, and an armature that is attached to the adsorption member. a support member rotatably supported in a direction toward and away from an end surface of the member, the support member being attached to the substrate within a plane perpendicular to the end surface of the suction member and the rotation plane of the armature, respectively; A magnetic force drive device, characterized in that a holding part is provided for movably holding the support member, and the position of the supporting member is adjusted and fixed to the holding part with the armature in close contact with the end face of the adsorption member. (2) Utility Model Registration In claim 1, the armature is composed of a pair of levers made of a magnetic member that is attracted to and released from both end surfaces of the attraction member, and the support member is 1. A magnetic drive device comprising a pair of yoke members which are movably held at the yoke member and rotatably support each lever in a direction toward and away from an end surface of an adsorption member. (3) Utility Model Registration The magnetic drive device according to claim 2, wherein one side of the pair of levers and the pair of yoke members has a lower magnetic resistance than the other side.