JPH01304436A - Electromagnetic actuator and shutter device for camera - Google Patents

Abstract

PURPOSE:To increase a turning power for opening and closing a shutter without enlarging a device by making an attractive force act to the movable member of an actuator in the same direction as the turning direction thereof. CONSTITUTION:The edge parts 1-1 and 1-2 of the movable member 1 respectively pinch driving pins 16 and 17 so that they can turn in maximum turning positions (a) and (b). The driving pins 16 and 17 are respectively engaged with the oblong holes 14 and 15 of shutter blades 10 and 11. The blades 10 and 11 turn centering around fixed shafts 12 and 13 accompanied with the turning of the member 1 and the shutter is opened and closed. When an electromagnetic winding joining a 3rd yoke 9 is not excited with such a constitution, the member 1 is attracted to the position (a) by 1st and 2nd yokes 7 and 8 joined with a permanent magnet 6 and the blades 10 and 11 are closed. Meanwhile, when the electromagnetic winding is excited, the member 1 is attracted to the position (b) and the blades 10 and 11 are opened. Thus, the attractive force in the same direction as the turning direction of the member 1 acts to the member 1, so that the turning power for opening and closing the shutter is increased.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electromagnetic actuator and a camera shutter device using the electromagnetic actuator.

[Description of Prior Art] As one of the prior art related to the present invention, there is an electromagnetic actuator described in Japanese Patent Application No. 62-291679, which was previously proposed by the present applicant. This includes a movable member that is rotatably held, a permanent magnet means that attracts the movable member toward one maximum rotation position device, and a permanent magnet means that cancels the attraction force of the permanent magnet means to move the movable member to the other maximum rotation position. The permanent magnet means and the yoke of the electromagnetic means protrude in an arc shape so as to face the arc-shaped end face of the movable member at a certain distance, and the movable member and the yoke The structure is such that the movable member is attracted toward one or the other maximum rotation position by generating a suction force that increases the opposing area between the two.

[Problem to be Solved by the Invention 1 According to the prior art described in L, the direction of the suction force acting on the ulI between the yoke and the movable member does not match the rotating direction of the 5f movable member, and therefore the suction force Since only the component force in the rotational direction acts on the movable member as rotational force, the force for rotating the movable member becomes weak, and when used as an actuator for opening and closing the shutter of a camera, In order to obtain the rotational force required to open and close the shutter, the size of the camera must be increased, which poses problems such as making it difficult to store the camera in a movable mirror.

The present invention has been made based on the above viewpoints, and [1]
The purpose is to provide an electromagnetic actuator that can obtain rotational force for opening and closing a camera shutter without increasing the size of the structure, and to provide a camera shutter device using the electromagnetic actuator. .

[Means for Solving the Problems] In the present invention, the intermediate portion is pivotally supported by an elongated plate-like member made of a magnetic material and can freely rotate between one maximum rotation position and the other maximum rotation position. a movable member, and a permanent magnet and a first yoke and a second yoke joined to different magnetic pole faces of the permanent magnet, and the movable member is attracted by the first and second yokes, so that the movable member is permanent magnet means for rotating the member toward the one maximum rotation position, an item spring wire, and a third yoke, and magnetization of the electromagnetic winding causes attraction of the permanent magnet means to the movable member. an electromagnetic means for rotating the movable member toward the other maximum rotation position by generating magnetic flux in a direction to cancel the force and attracting the movable member by the third yoke, one end of the movable member; On the other end side of the movable member, the first yoke and the third yoke face each other across the movable member in the rotating direction of the movable member, and on the other end side of the movable member, the first yoke and the third yoke face each other across the movable member. The above object is achieved by an electromagnetic actuator that faces the third yoke across the movable member in the rotating direction of the movable member.

The camera shutter device includes the electromagnetic actuator;
It is constituted by a shutter blade configured to be openable and closable, and means for engaging the movable member and the shutter blade so that the shutter blade is opened and closed by rotation of the movable member.

[Function] According to the magnetic actuator having the above configuration, the yoke is
They face each other with a movable member sandwiched in the direction of rotation of the first moving member, and a suction force is generated between the yoke and the AF moving member in the same direction as the rotating direction of the movable member, causing the first moving member to move to one side. Alternatively, since the movable member is attracted toward the other maximum rotational position, the generated suction force itself acts as a force for rotating the movable member, and a large rotational force can be obtained without increasing the size of the structure.

[Embodiments of the Invention] Fig. 1 is a configuration diagram showing an embodiment of an electromagnetic actuator according to the present invention, Fig. 2 (A) is a bottom view of the structure of Fig. 1 viewed from the entrance direction, and Fig. 2 (B) 1 is a top view of the structure shown in FIG. 1 viewed from direction B, and FIG. 3 is a perspective view showing the arrangement of a first yoke, a second yoke, and a third yoke in the structure shown in FIG.

In the figure, 1 is a movable member. The movable member l is an elongated plate-like member made of a magnetic material, and its both ends 1-1. It is received in a way that projects outward from the outside. The movable member 1 is connected at its center to a shaft 4 that intersects the plate surface of the movable member 1 in a criss-cross manner, and is held within the through space 3 of the winding frame 2 via this shaft 4. It is rotatable between one maximum rotation position 2ta and the other maximum rotation position. The winding frame 2 has three rectangular collar portions 2a, 2b, and 2e, and two winding grooves are formed by these collar portions. The collar portions 2a and 2C are provided at both ends of the winding frame 2, and the collar portion 2b is provided between the collar portions 2a and 2C. The middle collar portion 2b is thick, and the sleeve 4 is rotatably held at this collar portion 2b. Electromagnetic windings 5a and 5b are wound around the two winding grooves, respectively. The electromagnetic windings 5a and 5b are provided to generate magnetic flux in the same direction, and are excited so that the magnetic flux in the opposite direction to the magnetic flux of the permanent magnet 6, which will be described later, passes through the movable member l. In addition, both ends 1-1.1-2 of the movable member l
A bifurcated engaging portion is formed on the holder, and one engaging portion is connected to a bottle for opening and closing a shutter blade, for example.

6 is a permanent magnet provided under the winding frame 2. The permanent magnet 6 is a rectangular plate-shaped magnet, the upper surface of which engages with the lower surface of the collar portion 2b of the winding frame 2, and the opposing side surfaces 6a and 6b have different polarities. The side surface 6a is magnetized so as to be a north pole and the other side surface 6b is a south pole.

7 and 8 are a first yoke and a second yoke, which, as is clear from FIG. It is a shaped frame. In the first yoke 7, the base 7-1 is joined to one side 6a of the permanent magnet 6, and the suction part 7-2 is connected to the movable member l.
The end portion of the winding frame 2 on the side of the collar 2a is joined to one side of the maximum rotation position a so as to face one suction portion 9-2 of the third yoke 9, which will be described later. The second yoke 8 is
The base 8-1 is joined to the other side surface 6b of the permanent magnet 6, and the attraction part 8-2 faces the other attraction part 9-3 of the third yoke 9, which will be described later, across the movable member l. Like, a
The end portion of the frame 2 on the side of the collar portion 2c is joined to one side of the maximum rotation position a. Such first and second yokes7.
8, the magnetic flux of the permanent magnet 6 passes through the movable member 1 from one end 1-1 of the movable member 1 to the other end 1-2, and the movable member 1 is attracted to one maximum rotation position a. A suction force is generated to do this.

9 is the third yoke, and as is clear from FIG. 3, it is a substantially U-shaped frame that connects the base 9-1 and the two suction parts 9-2 and 9-3 that are integrated with the base 9-1. It is. Base 9 of third yoke 9
-1 is joined to the L surface of the collar portion 2b of the winding frame 2. One suction part 9-2 of the third yoke 9 is connected to the collar part 2 of the winding frame 2.
The end portion on the a side is joined to the other maximum rotation position side, and faces the suction portion 7-2 of the first yoke 7 with the movable member 1 in between. The other suction part 9-3 of the third yoke 9 is 1
The end of the winding frame 2 on the side of the collar zC is connected to the other side where the maximum rotation is located, and the second yoke 8 is connected with the movable member 1 in between.
The suction section 8-2 faces the suction section 8-2. With such a third yoke 9, when the electromagnetic windings 5a and 5b are excited so that the magnetic flux in the opposite direction to the magnetic flux of the permanent magnet 6 passes through the movable member 1, the movable member 1 is moved to the other maximum rotational position. 'j! A suction force is generated to attract it toward 1b.

With the above configuration, if the electromagnetic windings 5a and 5b are de-energized, the windings move from one end 1-1 of the movable member 1 to the other end 1-2 of the 01 moving member 1. The magnetic flux of the permanent magnet 6 passes through, and the movable member 1 is attracted to one maximum rotation position a.

Suction part 7-2.8- of first yoke 7 and second yoke 8
2 is located at one maximum rotational position ma side and faces the plate surface of the movable member l, and the direction of the suction force by the suction part 7-2.8-2 and the rotational direction of the member 1 are i=ro. Since they match, the generated suction force itself acts as a force for rotating the movable member 1. On the other hand, the electromagnetic windings 5a and 5b are arranged so that the magnetic flux in the opposite direction to the magnetic flux of the permanent magnet 6 passes through the movable member l.
When the permanent magnet 6 is excited, the magnetic flux of the permanent magnet 6 is canceled and the third
Magnetic flux flows from the other attraction part 9-3 of the yoke 9 through the movable member l and enters the one attraction part 9-2 of the third yoke 9, and the movable member l is attracted toward the other maximum rotation position. Ru. The suction part 9-2.9-3 of the third yoke 9 is located on the side of the other maximum movable position and faces the plate surface of the movable member l, and the suction force of the suction part 9-2.9-3 is Since the direction of rotation of the movable member 1 is the same, the generated suction force itself acts as a force for rotating the movable member 1. electric rj
By changing the magnitude of the excitation current of the i-windings 5a and 5b, the attractive force acting on the movable member 1 changes, and the rotational speed of the movable member 1 toward the other maximum rotational position changes.

When the excitation of the electromagnetic windings 5a and 5b is cut off, the attractive force of the permanent magnet 6 acts on the movable member 1, and the movable member 1 is returned to one of the maximum rotational positions a.

According to the prototype made by one of the present authors, the length and breadth of the bar are 18 mm, the width is 7 mm, and the length of the movable member 1 (7) is about 30 mm, compared to the conventional technology made with similar dimensions. It is possible to obtain more than three times the rotational force compared to the one mentioned above, which is more than the rotational force required to open and close the shutter, and it can be easily stored in a movable lens barrel. It was confirmed that there is.

FIG. 4 is a configuration diagram showing an embodiment of a camera shutter device using the electromagnetic actuator having the configuration shown in FIG. In FIG. 4, the same reference numerals as in FIG. 1, FIG. 2(A), FIG. 2(B) and FIG. 3 represent the same thing.

In FIG. 4, shutter blades 10 and 11 are rotatably supported by fixed shafts 12 and 13, respectively. The shutter blade 10.11 has elongated holes 14, 15 in the arm portion,
The long hole 14 of the shutter blade 10 engages with the drive pin 16 held between the one end 1-1 of the movable member 1 of the electromagnetic actuator, and the long hole 15 of the shutter blade 11 engages with the drive pin 16 held at the other end 1-1 of the movable member 1 of the electromagnetic actuator. -2 is engaged with the drive bin 17 held between the two. The shutter blade 10.11 closes the aperture 18 of the imaging lens when the movable member 1 rotates toward one maximum rotation position a, and closes the opening 18 of the imaging lens when the movable member 1 rotates toward the other maximum rotation position. The opening 18 is opened by rotating in the opposite direction.

According to such a configuration, when the electromagnetic windings 5a and 5b are de-energized, the movable member l is attracted to one maximum rotation position a, the shutter blade Mi10.11 is in the open state, and the electromagnetic winding By energizing the wires 5a and 5b, the gJ member 1 is attracted toward the other maximum rotation position, and the shutter blades 10.11 are opened. By changing the magnitude of the excitation current of the electromagnetic windings 5a and 5b, the rotational speed of the movable member 1 changes and the opening speed of the shutter blades 10.11 changes, so it is possible to change the shutter opening characteristics with a cylinder configuration. Become.

In the embodiment shown in FIG. 4, the movable member 1 of the electromagnetic actuator is directly engaged with the shutter blade 10.11 to open and close the shutter blade 10.11, but the configuration is not limited to this. Of course, any structure may be used as long as the shutter blades are opened and closed by the rotational movement of the movable member 1.

[Effects of the Invention] As explained below, according to the present invention, the suction force is applied to the movable member in the same direction as the rotation direction of the movable member, so that the generated suction force itself causes the movable member to rotate. It is possible to provide an electromagnetic actuator that acts as a force for moving the shutter and can obtain rotational force for opening and closing the shutter without increasing the size, and also allows the shutter opening characteristics to be varied.
It is possible to provide a camera shutter device that can be easily stored in a movable lens barrel.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing one embodiment of the electromagnetic actuator according to the present invention, FIG. 2(A) is a bottom view of the configuration of FIG. 1 viewed from direction A, and FIG. 2(B) is the configuration of FIG. 1. 3 is a perspective view showing the arrangement of the first yoke, second yoke, and third yoke in the configuration of FIG. 1, and FIG. 4 is a top view of the electromagnetic actuator with the configuration of FIG. FIG. 2 is a configuration diagram showing an example of the shutter device δ of the camera used. l... Movable member 5a, 5b... Electromagnetic winding 6...
・Permanent magnet 7...First yoke 8...Second yoke 9...Third yoke 10.11...Shutter blade

Claims (1)

[Claims] 1) A movable member whose intermediate portion is pivotally supported by an elongated plate-like member made of a magnetic material and is rotatable between one maximum rotational position and the other maximum rotational position; It has a magnet and a first yoke and a second yoke joined to different magnetic pole faces of the permanent magnet, and the movable member is attracted by the first and second yokes to rotate the movable member to the maximum rotation of the one. permanent magnet means for pivoting towards the moving position, an electromagnetic winding and a third
and a yoke, by excitation of the electromagnetic winding, a magnetic flux is generated in a direction that cancels the attractive force of the permanent magnet means against the movable member, and the movable member is attracted by the third yoke, thereby causing the movable member to electromagnetic means for rotating the other movable member toward its maximum rotational position, and on one end side of the movable member, the first yoke and the third yoke are movable in the rotational direction of the movable member. An electromagnetic actuator in which the second yoke and the third yoke face each other across the movable member, and on the other end side of the movable member, the second yoke and the third yoke face each other across the movable member in the rotating direction of the movable member. 2) The electromagnetic actuator according to claim 1, a shutter blade configured to be openable and closable, and the movable member and the shutter blade such that the shutter blade is opened and closed by rotation of the movable member according to claim 1. and means for engaging the camera.