JPS622591Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic drive device, and particularly to a small magnetic drive device suitable for being installed inside a camera or the like.

In recent years, cameras have become increasingly automated, and small magnetic drive devices are often used to drive shutters, apertures, mirrors, and the like. This type of magnetic drive device needs to be extremely compact because it is installed inside a camera, and is also required to have high output, high mechanical precision, and durability in order to prevent malfunctions.

FIG. 1 shows a schematic configuration of a conventional magnetic drive device. In this figure, a coil 2 is wound around a flat yoke 1 to constitute an electromagnet 3, and an armature 4 made of a magnetic material such as iron is opposed to the electromagnet 3 so as to be able to be attracted to and removed from the electromagnet. This armature 4 is rotatable at its center via a drum-shaped shaft 5 to an armature holder 6.
Moreover, it is supported so as to be able to swing up and down about the axial center of the shaft 5 . A stopper 7 is integrally installed on the armature holder 6, and
A predetermined gap is formed between the stopper 7 and the armature 4, and a leaf spring 8 is interposed within this gap to bias the armature 4 in a direction that brings the armature 4 into close contact with the end surface of the yoke 1. Further, a tension spring 9 is interposed between the armature holder 6 and the device main body (not shown), and the tension spring 9 causes the armature 4 to move away from the magnet 3 against the attractive force of the magnet 3. The armature 4 is separated from the magnet 3 when the coil 2 is not energized.

In such a configuration, in order to maximize the attraction force of the armature 4 by the magnet 3 when the coil 2 of the magnet 3 is energized, the end face of the yoke 1 of the magnet 3 and the end face of the armature 4 must be It is necessary to make close contact in the Y-Y plane of FIG. 1 and in the plane perpendicular to the paper plane of FIG. Therefore, in the conventional magnetic drive device, as described above, a predetermined gap is formed between the armature 4 and the stopper 7, and
The armature 4 is rotatably supported on a drum-shaped shaft 5, so that close contact in the Y-Y plane can be adjusted by rotating in the direction of arrow A in FIG. is adjusted by swinging around the central bulge (not shown) of the shaft 5. At this time, the yoke 1 and the armature 4 are urged in the direction of close contact by the leaf spring 8, and the position of the armature 4 is adjusted by this urging force.

However, in such a conventional structure, it is not possible to insert the leaf spring 8 in a small gap between the armature 4 and the stopper 7, for example, a gap of about 0.5 to 2 mm, with a good balance of pressing force. This is extremely difficult and increases the manufacturing cost, and if the balance of the leaf spring 8 is lost or the armature 4 shakes, the armature 4 will move toward and away from the yoke 1 at an angle, rather than at both ends at the same time. This reduces the holding force of the armature 4 by the magnet 3, and causes an abnormally worn part due to friction to occur at the corner of the end face of the yoke 1 due to the contact and separation of the armature 4 many times. This has the disadvantage that the contact area of the armature is reduced, and the holding force of the armature by the magnet 3 is reduced, impairing the stability of holding, that is, the stability of operation.

In addition, when incorporating such a magnetic force drive device into an actual camera, etc., the armature holder 6
Since the movement of the device is taken out to the outside to release the latch of the shutter, etc., it is difficult to seal the entire device. For this reason, there is a possibility that dust may enter the contact surface between the yoke 1 and the armature 4. In particular, if magnetic substances such as iron powder adhere to the contact surface, the adsorption force of the armature 4 will be significantly deteriorated, and the magnetic drive There are drawbacks that can cause the device to malfunction.

In the example shown in FIG. 1, an electromagnet is used as the magnet 3, and when the coil 2 is energized, the armature 4
The armature 4 is pulled from the magnet 3 by using a permanent magnet as the magnet 3, and by winding a coil around the permanent magnet to cancel out the magnetic force of the permanent magnet when the coil is energized. Although there are devices configured to separate the magnets from each other, such devices also have the same drawbacks as mentioned above, and in particular, the permanent magnet has the drawback that magnetic powder tends to adhere to it. Also, the shaft 5 is not necessarily drum-shaped with a thick center, but there are also straight shafts,
This case also has the same drawbacks as described above.

Furthermore, a magnetic force drive device that is compact and capable of stable operation for a long period of time is desired not only for cameras but also for other devices.

The purpose of this invention is to create a magnetic drive that does not require the difficult work of inserting leaf springs in conventional systems, can operate stably for a long period of time without the adhesion of magnetic materials, and can be made more compact. We are in the process of providing equipment.

In the present invention, a rotating magnetic pole is provided opposite to a fixed magnetic pole so that the rotating magnetic pole can be rotated by a predetermined angle by a drive signal, and the rotating magnetic pole is always urged in a predetermined direction by a first urging means. A cam portion is formed by cutting the shaft of the rotating magnetic pole in a direction perpendicular to its axis, and an actuation lever is removably provided on the cam portion, and the actuation lever is pushed into the cam portion by a second biasing means. When the rotating magnetic pole rotates by a predetermined angle against the first urging means, the cam portion and the operating lever are unlocked and the second urging means The operating lever is driven in a predetermined direction, and a dustproof cover is provided to cover at least a portion including the fixed magnetic pole and rotating magnetic pole, so that the magnetic pole portion is configured like a kind of motor and dustproof. In addition to ensuring completeness,
This aims to achieve the above object by eliminating the need for adjustment work using leaf springs.

Hereinafter, embodiments of the present invention will be described based on the drawings.

FIG. 2 shows the basic configuration of the present invention.
In this figure, a fixed magnetic pole 11 consisting of a pair of permanent magnet pieces with different magnetic properties is housed and fixed in a dustproof case 12 made of an iron plate or the like and also serving as a yoke. Inside this dustproof case 12, a rotating magnetic pole 13 is arranged opposite to the fixed magnetic pole 11. The rotating magnetic pole 13 includes a shaft 14 rotatably supported by a dustproof case 12, and a core 1 fixed to the shaft 14 and positioned between a pair of permanent magnet pieces constituting the fixed magnetic pole 11.
5 and is wound around this core 15, and when energized, the core 15
The coil 16 magnetizes the coil 1.
6 is connected to a battery 18 via a switch 17. At this time, the winding direction of the coil 16 is such that when the coil 16 is energized, the S pole is excited at the end of the core 15 on the side opposite to the N pole of the fixed magnetic pole 11, and the S pole is excited at the end of the core 15 on the side opposite to the S pole of the fixed magnetic pole 11. core 15
A north pole is excited at the end of the .

One end of a first tension spring 19 as a first biasing means is attached to the rotating magnetic pole 13, and this tension spring 19 causes the rotating magnetic pole 13 to be biased in a predetermined direction, clockwise in FIG. At the same time, it is stopped at a predetermined position by a stopper 20. The stop position by this stopper 20 is the center position of the magnetic pole excited in the core 15 when the coil 16 is energized,
The position is such that the center position of the magnetic pole of the fixed magnetic pole 11 is shifted by a predetermined angle.

One end of the shaft 14 projects from the dustproof case 12, and a cam portion 21 is integrally formed on this projecting end by flattening or the like. Most of the cam part 21 is cut out from one side of the shaft 14 beyond the central axis, and the cross section perpendicular to the axis is processed to have a substantially thin semicylindrical shape or crescent shape. One end of the operating lever 22 is removably locked. The operating lever 22 is rotatably supported in the middle by a pin 23, and a second biasing means is provided at the end opposite to the locking part to the cam part 21 by sandwiching the pin 23. One end of a second tension spring 24 is attached, and the biasing force of this spring 24 biases one end of the actuating lever 22 so that it is always locked to the cam portion 21 in the state shown in FIG. Furthermore, an operating section 25 for operating a driven section (not shown) is formed at the end of the operating lever 22 on the side where the tension spring 24 is attached.

In such a configuration, when the switch 17 is released and the coil 16 is not energized, the core 15 is positioned at a position offset from the magnetic pole center of the fixed magnetic pole 11 by the first tension spring 19, and in this state, the core 15 is located at a position offset from the magnetic pole center of the fixed magnetic pole 11. The portion 21 and one end of the operating lever 22 are locked.

Next, when the switch 17 is turned on and a drive signal is applied to the coil 16, the core 15 is moved to the coil 16.
The end of the fixed magnetic pole 11 closer to the N pole is magnetized, and the end of the fixed magnetic pole 11 closer to the S pole is excited to have an N pole. The core 15 is rotated counterclockwise in the figure against the biasing force. Therefore, the shaft 14 is also rotated, and the direction of the cam portion 21 having a substantially crescent-shaped cross section changes, and the tip of the actuating lever 22, which has been locked to the corner of the circumferential surface of the cam portion 21, comes off. Since the actuating lever 22 is biased counterclockwise in the figure by the second tension spring 24, it rotates counterclockwise at the same time as the actuating lever 22 and the cam part 21 are disengaged, and the operating part At step 25, a predetermined driven part is driven.

On the other hand, when the switch 17 is released again, the core 15 returns to its old position under the action of the first tension spring 19. In this state, if the actuating lever 22 is rotated clockwise against the second tension spring 24 using a lever or the like (not shown), the actuating lever 22
The tip of the cam part 21 is engaged with the cam part 21 to prepare for the next operation. At this time, the surface of the end of the actuating lever 22 that is locked to the cam part 21 on the opposite side from the cam part 21 side is formed into a rounded surface, so that the cam part 21 at the tip of the actuating lever 22 can easily pass through. It will be done.

According to such a configuration, since the fixed magnetic pole 11 and the rotating magnetic pole 13 are housed in the dustproof case 12, it is possible to effectively prevent magnetic materials such as iron powder from adhering to the magnetic pole parts. Further, since the shaft 14 is processed to form the cam portion 21 and the tip of the actuating lever 22 is locked to the circumferential surface of the cam portion 21, even if the biasing force of the second tension spring 24 is increased, the cam portion 21, that is, the shaft 14, can be easily rotated, and therefore the force for driving the core 15 may be weak, so that the core 15, the coil 16, and the fixed magnetic pole 11 can be made small. Furthermore, since the fixed magnetic pole 13 only needs to be rotated by a relatively small predetermined angle, the coil 1
6 and the battery 18 can be connected by using a lead wire with a little allowance, and unlike a motor, a commutator or the like is not required, and the structure is simple and maintenance is easy.

3 and 4 show a specific embodiment of the magnetic drive device of the present invention. In these figures, a flange portion 33 fixed by spot welding or the like is fixed on a substrate 31 at a position of 180 degrees on the circumferential surface of a dustproof case 32 with screws. The dust-proof case 32 includes a case body 34 formed by deep drawing a steel plate that also serves as a yoke, and crimping pieces that close the opening of the case body 34 and are integrally provided at the four corners of the case body 34. 35
A resin end bracket 36 is fixed to the case body 34 by means of a screwdriver, and a pair of terminals 37 are implanted in the end bracket 36.

A fixed magnetic pole 38 consisting of a pair of permanent magnets with different polarities is fixed to the inner wall of the case body 34,
A rotating magnetic pole 39 is provided opposite to the fixed magnetic pole 38 . This rotating magnetic pole 39 is connected to the case body 3
4, a shaft 40 rotatably supported within the end bracket 36 and having one end projected from the end bracket 36, and a core 4 fixed at a position corresponding to the fixed magnetic pole 37 of the shaft 40.
1 and a coil 42 wound around this core 41, and both ends of this coil 42 are connected to the terminal 37 via a lead portion with sufficient length. The coil 42 is wound so that when the coil 42 is energized, the magnetic poles are excited so that each end face of the core 41 is attracted to the nearby fixed magnetic pole 38 side.

A spring locking pin 43 is protruded from the end bracket 36 of the shaft 40, and a tension spring 44 is stretched between the pin 43 and the end bracket 36 as a first biasing means. The rotating magnetic pole 39 is biased clockwise in FIG. 3 by the spring 44. Further, the end bracket 36 is provided with a stopper 45, and the rotation of the spring locking pin 43 by the spring 44 is stopped by this stopper 45.

A cam portion 46 having a substantially crescent-shaped cross section perpendicular to the axis is integrally formed at the tip of the protruding portion of the shaft 40 from the end bracket 36. One end of an actuating lever 47 formed in a substantially Y-shape in plan and a locking portion 48 is locked to the corner of the circumferential surface of this cam portion 46. The cam part 46 is formed to stand up from the surface thereof, and the surface opposite to the contact surface with the cam portion 46 is a rounded surface.

The central part of the actuating lever 47 is rotatably supported on the upper part of a support shaft 49 erected on the base plate 31, and the end of the actuating lever 47 located on the opposite side from the locking part 48 is , is bent downward in FIG. 4, and this bent end is used as an operating section 50 connected to a driven part such as a shutter mechanism of a camera (not shown), and the remaining end of the Y-shape will be described later. This is a contact portion 51 with which the rising piece of the biasing lever comes into contact.

A biasing lever 52 is rotatably supported in the lower part of the support shaft 49, and a rising piece 53 is integrally provided on one end of the biasing lever 52, that is, on one side of the left end in the figure. This rising piece 53 is capable of coming into contact with one side end surface of the abutting portion 51 of the actuation lever 47, and between this rising piece 53 and the operating portion 50 of the actuation lever 47, there is a winding around the support shaft 49. Each end of a turned first torsion coil spring 54 serving as a second biasing means is interposed, and the first torsion coil spring 54 causes the rising piece 53 to move toward the abutting portion 51.
It is biased so that it always comes into contact with one side end surface.

The other end of the biasing lever 52, that is, the right end in the figure, is rotatably connected to one end of a long connecting lever 56 via a pin 55, and the other end of this connecting lever 56 is connected to a set lever 58 via a pin 57. It is rotatably connected to the tip of the The base end of the set lever 58 is connected to a support shaft 59 that is erected on the base plate 31.
Each end of a second torsion coil spring 60 wound around the support shaft 59 is interposed between the set lever 58 and the base plate 31. The set lever 58 is biased clockwise in FIG. 3 by the torsion coil spring 60. Further, the tip of the set lever 58 is bent downward in FIG. 4 to form a driven part 61, and this driven part 61 is latched to a film winding part of a camera (not shown), and is used to wind the film. When operated, the set lever 58 is moved from the solid line position in FIG. 3 to the chain line position.

Note that reference numeral 62 is a stopper of the set lever 58.

In such a configuration, when no force is applied to the driven portion 61 of the set lever 58, the second
Due to the action of the torsion coil spring 60, the set lever 58 is positioned at the solid line position in FIG. 3, and the connecting lever 56 and biasing lever 52 are also positioned at the solid line position. Therefore, the rising piece 53 of the biasing lever 52 comes into contact with one side end surface of the contact portion 51 of the actuating lever 47 due to the action of the first torsion coil spring 54, and the actuating lever 47 is moved clockwise in FIG. As a result, the locking portion 48 of the operating lever 47 is rotated clockwise in FIG. 3 and is positioned beyond the cam portion 46 formed at the upper end of the shaft 40. At this time, since the coil 42 of the rotating magnetic pole 39 is not energized, the core 41 is moved to the state shown in FIG. 3 by the tension spring 44, that is, the fixed magnetic pole 38
The center of the magnetic pole of the core 41 and the center of the magnetic pole excited by the coil 42 of the core 41 are shifted by a predetermined angle. Therefore, the rotation of the operating lever 47 in the counterclockwise direction in FIG. This is prevented by the engagement between 46 and the locking portion 48 .

Then, when the film of the camera is wound, the driven portion 61 is driven counterclockwise in FIG. 3 against the biasing force of the second torsion coil spring 60, and the set lever 58 moves toward the chain line in FIG. When located at this position, the biasing lever 52 is also rotated counterclockwise via the connecting lever 56, and is located at the position indicated by the chain line in FIG. Due to this rotation of the biasing lever 52, both ends of the first torsion coil spring 54 are deformed so that the angle formed by both ends becomes smaller, so that the biasing force becomes stronger and the actuating lever 47 is moved as shown in FIG. Attempts to rotate counterclockwise. On this occasion,
The rotation of the locking portion 48 of the operating lever 47 is caused by the shaft 4
0, the operating lever 47 is blocked by a cam portion 46 formed at the upper end of the locking portion 48 and the cam portion 4.
6 is held in a locked state.

In this state, when the shutter button of the camera is pressed and the coil 42 of the rotating magnetic pole 39 is energized, the core 41 is excited by the coil 42.
The rotating magnetic pole 39 is rotated counterclockwise in FIG. 3 by the attractive force with each fixed magnetic pole 38. Therefore, the cam portion 46 integrated with the shaft 40 is also rotated, and the engagement between the cam portion 46 and the locking portion 48 of the operating lever 47 is disengaged, and the operating lever 47 is moved by the biasing force of the first torsion coil spring 54. A sharp counterclockwise rotation,
An operating section 50 integrally formed with the operating lever 47,
The shutter operation is performed by releasing the latch of the shutter (not shown) and rapidly moving the shutter by the force of a preloaded spring.

When the shutter operation is completed in this manner, the film winding state is released, so the driven portion 61 of the set lever 58 is released, and the set lever 58 is moved back to its old position by the action of the second torsion coil spring 60, i.e., as shown in FIG. It will return to the solid line position. Therefore, the biasing lever 52 also returns to the old position via the connecting lever 56, and the operating lever 47, pushed by the rising piece 53 of the biasing lever 52, also returns to the old position. At this time, since the coil 42 has already been de-energized, the rotating magnetic pole 39 is in the state shown in FIG. 3 due to the biasing force of the tension spring 44, and therefore the cam portion 46 is also in the state shown in the drawing. Therefore, the tip of the locking portion 48 of the actuating lever 47 rotates the cam portion 46 against the tension spring 44 due to the action of the R surface formed on the tip, and moves to a position beyond the cam portion 46. everything is returned to its initial state and ready for the next operation.

This embodiment as described above also has the same effects as the basic configuration example.

In addition, in implementation, the first biasing means is not limited to a tension spring, and biasing means of other configurations may be used, such as a torsion coil spring having one end fixed to the shaft and the other end fixed to a dustproof case or the like. Further, the fixed magnetic pole is not limited to a permanent magnet, but may be an electromagnet, and the rotating magnetic pole is not limited to an electromagnet, but may also be a permanent magnet. Furthermore, the fixed magnetic pole and the rotating magnetic pole are not limited to those in which the magnetic pole centers are shifted as in each of the above embodiments, but may also be those in which the magnetic pole centers coincide when not energized, and the magnetic pole centers shift due to repulsion when energized. In short, it is sufficient that the rotating magnetic pole is driven by a predetermined angle when energized. Furthermore, the present invention can be applied not only to cameras but also to other devices.

As described above, according to the present invention, it is possible to operate stably for a long period of time without the need for adjustment work as in the conventional example, and without the occurrence of adhesion of magnetic material.
Moreover, there is an effect that a magnetic force drive device that can be further miniaturized can be provided.

[Brief explanation of drawings]

FIG. 1 is a plan view showing a schematic configuration of a conventional magnetic drive device, FIG. 2 is an explanatory diagram showing the basic structure of a magnetic drive device according to the present invention, and FIG. 3 is a plan view showing a specific embodiment of the present invention. FIG. 4 is a partially cutaway plan view, and FIG. 4 is a front view of FIG. 3. 11,38...Fixed magnetic pole, 12,32...Dust-proof case, 13,39...Rotating magnetic pole, 14,40...
...shaft, 15,41...core, 16,42...
... Coil, 19, 44 ... Tension spring as first biasing means, 21, 46 ... Cam portion, 22, 47
... Actuation lever, 24, 54 ... Tension spring and torsion coil spring as second biasing means, 25,
50... Operating section, 48... Locking section.

Claims (1)

[Scope of utility model registration request] A fixed magnetic pole, a rotating magnetic pole that faces the fixed magnetic pole and is driven to rotate at a predetermined angle with respect to the fixed magnetic pole about the shaft by a drive signal, and a first bias that urges the rotating magnetic pole in a predetermined direction. means, a cam portion formed by cutting out the shaft of the rotating magnetic pole in a direction perpendicular to the axis thereof, and a cam portion that is removably engageable with the circumferential surface of the cam portion and that is normally biased by a second biasing means. an actuating lever that is locked to the surface and is unlocked from the peripheral surface of the cam portion when the rotating magnetic pole rotates and is rotated by a predetermined angle by the urging force of the second urging means; A magnetic drive device comprising: a dustproof case that covers a portion including a magnetic pole and a rotating magnetic pole, and in which a cam portion of the shaft protrudes to the outside.