JP5323379B2 - Electromagnetic actuator and camera blade drive device - Google Patents

Description

  The present invention relates to an electromagnetic actuator that generates a rotational driving force by electromagnetic force, and in particular, includes a rotor having a magnetized outer peripheral surface, a yoke that forms a magnetic pole portion facing the outer peripheral surface of the rotor, and the like, and a shutter blade of a camera The present invention relates to an electromagnetic actuator applied when driving blade members such as a diaphragm blade and an ND filter blade and a blade driving device for a camera using the electromagnetic actuator.

  As a conventional electromagnetic actuator, it has a cylindrical outer peripheral surface magnetized by being divided into N and S poles and can rotate within a predetermined angle range, an exciting coil, and opposed to the outer peripheral surface of the rotor And a substantially U-shaped yoke having a first magnetic pole part and a second magnetic pole part that have different arcuate surfaces and generate different magnetic poles when the coil is energized. And a drive pin that outputs a rotational driving force to the outside, and a protrusion that protrudes from the outer peripheral surface of the rotor and is magnetized to the same magnetic pole as the outer peripheral surface. What is formed so that the side surface of the protrusion (the side surface facing the rotation direction, that is, the circumferential direction) and the end surface of the magnetic pole portion of the yoke are opposed to each other when positioned at the rotation end (see, for example, Patent Document 1). .

However, in this electromagnetic actuator, since the side surface (side surface facing the rotation direction) of the protrusion is opposed to the end surface of the tip of the yoke, the magnetic attractive force between the side surface of the protrusion and the end surface of the yoke In order to increase the rotational torque associated with the magnetic repulsive force, it is necessary to increase the amount of protrusion of the protrusion (the amount of protrusion from the outer peripheral surface in the radial direction of the rotor). This is contrary to increasing the size and improving the responsiveness.
In addition, since the drive pin and the protrusion are provided at different angular positions in the rotational direction of the rotor, it is necessary to secure the mechanical strength by making the drive pin and the protrusion thick.
JP 2006-288036 A

  The present invention has been made in view of the above circumstances, and an object of the present invention is to form an efficient magnetic circuit between a rotor and a yoke while reducing the size and to achieve a desired driving torque. Electromagnetic actuator capable of generating a stable rotational driving force or holding force when applied as a driving source for driving a blade member such as a shutter blade, a diaphragm blade, or an ND filter blade of a camera, ensuring a magnetic attraction force, etc. And providing a blade drive for a camera using the same.

The electromagnetic actuator of the present invention includes a cylindrical outer peripheral surface and a rotor that protrudes in a radial direction from the outer peripheral surface and has a drive pin that exerts a driving force to the outside, and can rotate a predetermined rotation range, an excitation coil, An electromagnetic actuator comprising a yoke having a first magnetic pole portion and a second magnetic pole portion that define an arcuate opposing surface that faces the outer peripheral surface of the rotor and that generate different magnetic poles when energized to the coil, The rotor is arranged so as to have a rotation center in an inner region sandwiched between the first magnetic pole part and the second magnetic pole part of the yoke, defines an outer peripheral surface, and is magnetized with different magnetic poles in the circumferential direction. The yoke includes a rotor portion, a projecting portion magnetized by the same magnetic pole as the outer circumferential surface, and defining an end surface that projects radially outward from the outer circumferential surface and a side surface facing the circumferential direction. 1 magnetic pole or 2nd magnet In part, when the rotor is positioned at the rotation end of the rotation range, having an end face facing portions formed by bending in a substantially L shape such that the end face opposed facing radially outward of the projecting portion, as characterized by Yes.
According to this configuration, the rotor has an end surface that protrudes radially from the outer peripheral surface of the magnetized rotor portion and faces the radially outer side and a side surface that faces the circumferential direction (rotation direction of the rotor) and is identical to the outer peripheral surface. When a protrusion magnetized on the magnetic pole is provided and the rotor is located at the rotation end of the rotation range (one rotation end or the other rotation end), the end surface of the protrusion that faces radially outward is the yoke first. to face the Oite substantially L-shaped in form by bending the end surface facing portion to one magnetic pole portion and the second magnetic pole portion increases the magnetic attraction force or magnetic repulsive force between the projecting portion and the yoke be able to.
That is, when the coil is not energized, it is strong between the outer peripheral surface of the magnetized rotor portion and the arc-shaped opposing surface of the yoke, and between the end surface of the protruding portion and the end surface opposing portion of the first magnetic pole portion or the second magnetic pole portion. A stable holding force that stops the rotor at the rotating end of the rotation range is obtained by generating a magnetic attraction force, and on the other hand, when energizing the coil, the outer peripheral surface of the magnetized rotor portion and the arc-shaped opposing surface of the yoke A strong repulsive force due to electromagnetic force is generated between the end face of the protrusion and the end face of the protruding part and the end face facing part of the first magnetic pole part or the second magnetic pole part, and a stable driving torque for rotating the rotor is obtained.
Thus, by forming an efficient magnetic circuit between the rotor and the yoke, a desired driving torque, magnetic biasing force (magnetic attractive force, magnetic repulsive force), etc. can be achieved while achieving miniaturization. It is possible to ensure the strength of holding the rotor at the rotation end, increase the speed of the rotor, and the like.

In the above configuration, the magnetized rotor portion has an N pole outer peripheral surface and an S pole outer peripheral surface that are divided in the circumferential direction, and the projecting portion protrudes from one of the N pole outer peripheral surface and the S pole outer peripheral surface. The formed configuration can be adopted.
According to this configuration, the driving torque required while simplifying the structure can be obtained because it is only necessary to provide a protrusion on the outer peripheral surface and magnetize the same magnetic pole as the outer peripheral surface of the conventional rotor. In addition, the magnetic biasing force can be easily set.

In the configuration described above, a configuration in which the protruding portion is integrally formed by protruding from the outer peripheral surface in the same direction as the drive pin can be adopted.
According to this configuration, since the projecting portion and the drive pin are integrally formed and project from the outer peripheral surface of the rotor, it is possible to increase the mechanical strength while achieving downsizing.

In the above-described configuration, the yoke may employ a configuration in which the first magnetic pole portion or the second magnetic pole portion has a side facing portion that faces the side surface of the protruding portion when the rotor is positioned at the rotation end of the rotation range. .
According to this configuration, when the rotor is positioned at the rotation end (one side rotation end or the other side rotation end) of the rotation range, the end surface of the protrusion is formed on the first magnetic pole portion or the second magnetic pole portion of the yoke. Opposite to the end face facing portion (for example, the first end face facing portion formed on the first magnetic pole portion or the second end face facing portion formed on the second magnetic pole portion) and the side surface of the protruding portion is the first magnetic pole portion or A projecting portion to face a side facing portion formed on the second magnetic pole portion (for example, a first side facing portion formed on the first magnetic pole portion or a second side facing portion formed on the second magnetic pole portion); The magnetic attraction force or magnetic repulsion force with the yoke can be further increased.

In the above configuration, the yoke is formed to be bent in a substantially U shape so as to have the first magnetic pole portion on one end side and the second magnetic pole portion on the other end side, and the rotor is at the rotation end on one side of the rotation range. A first end face facing portion formed on the first magnetic pole portion to face the end face of the protruding portion when positioned, and a second end face to face the end face of the protruding portion when the rotor is positioned at the rotation end on the other side of the rotation range. The yoke is formed by a first yoke having a first magnetic pole portion and a second yoke having a second magnetic pole portion, which are bisected so as to be joined. The configuration can be adopted.
According to this configuration, when the rotor is positioned at the rotation end on one side of the rotation range, the end surface of the projecting portion faces the first end surface facing portion formed in the first magnetic pole portion of the yoke (and the yoke is In the case of including one side facing portion, the side surface of the protruding portion faces the first side facing portion formed on the first magnetic pole portion), so that the holding force (magnetically) when the rotor is positioned at the one rotation end is determined. (Suction force) can be increased, and the rotational torque when rotating from one rotational end to the other rotational end can be increased, while the rotor rotates on the other side of the rotational range. When positioned at the end, the end surface of the projecting portion faces the second end surface facing portion formed on the second magnetic pole portion of the yoke (and when the yoke includes the second side facing portion, the side surface of the projecting portion is To face the second side facing portion formed in the second magnetic pole portion) The holding force (magnetic attraction force) when the rotor is located at the rotation end on the other side can be increased, and the rotational torque when rotating from the rotation end on the other side toward the rotation end on one side can be increased. Can be increased.
Further, since the yoke is substantially U-shaped and is divided into a first yoke and a second yoke, even if the tip side of the first magnetic pole portion or the second magnetic pole portion is bent in an L shape, for example, the coil Can be easily inserted into and fixed to a bobbin or the like that winds, improving the assembly workability.
Here, the first yoke and the second yoke may have a joining piece formed in a thinner plate shape than the first magnetic pole part and the second magnetic pole part so as to be overlapped and joined to each other. In this case, since the first yoke and the second yoke can be joined by overlapping the thin plate-like joining pieces, the area of the magnetic path in the joining region can be sufficiently secured, and they are integrally formed. Similar to the yoke, it can be formed with the same thickness.

A camera blade driving device according to the present invention includes a substrate having an opening through which subject light passes, a blade member movably provided between a position facing the opening and a retracted position retracted from the opening, and the blade member And a drive source that drives any one of the above-described electromagnetic actuators.
According to this configuration, since the electromagnetic actuator described above is employed as a driving source, a sufficient driving force is output from the rotor and the blade member is reliably stabilized at a desired timing while achieving downsizing of the apparatus. And is held at a predetermined position (for example, a position facing the opening or a position retracted from the opening).

According to the electromagnetic actuator having the above configuration, in the protruding portion that protrudes radially outward from the outer peripheral surface of the rotor and is magnetized to the same magnetic pole as the outer peripheral surface, and the first magnetic pole portion or the second magnetic pole portion of the yoke, By providing the end face facing portion that can face the end face facing the radially outer side of the protruding portion, it is possible to obtain an electromagnetic actuator that generates a desired magnetic holding force and driving torque while achieving miniaturization.
In addition, according to the camera blade drive device having the above-described configuration, since the above-described electromagnetic actuator is employed as a drive source, the blade member can be obtained with sufficient drive torque obtained by the rotor while achieving downsizing of the device. (For example, shutter blades, diaphragm blades, ND filter blades, etc.) can be reliably and stably driven at a desired timing, and are reliably held at a position facing the opening or a position retracted from the opening. be able to.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
1 to 9 show an embodiment in which an electromagnetic actuator according to the present invention is applied to a blade driving device for a camera. FIG. 1 is an exploded perspective view of the device, FIG. 2 is a plan view of the device, and FIG. 4 is a rear view of the apparatus, FIG. 4 is a sectional view of the apparatus, FIG. 5 is a perspective view of a rotor that forms part of the electromagnetic actuator, FIG. 6 is a plan view of the rotor and yoke that form part of the electromagnetic actuator, and FIG. FIG. 8 and FIG. 9 are plan views showing a state in which the blade member is retracted from the opening and is in a position facing the opening.

As shown in FIGS. 1 to 4, the camera blade driving device includes a base plate 10 and a back plate 20 as substrates having openings 10 a and 20 a through which subject light passes, and positions and openings facing the openings 10 a and 20 a. The blade member 30 is supported by the base plate 10 so as to be freely movable between the retreat positions retracted from 10a and 20a, the electromagnetic actuator M as a drive source for driving the blade member 30, and the like.
As shown in FIG. 1, the electromagnetic actuator M includes a rotor 100, a substantially U-shaped yoke 110, an exciting coil 120, a holding member 130 that winds the coil 120 and fixes the yoke 110, and the like.

As shown in FIGS. 1 to 4, the base plate 10 passes through a circular opening 10 a for passing subject light, a support shaft 11 that rotatably supports the rotor 100, and a drive pin 103 of the rotor 100 described later. The substantially circular arc-shaped through hole 12, the concave portion 13 for positioning the yoke 110, the screw hole 14 for screwing the screw B, the support shaft 15 for rotatably supporting the blade member 30, and the blade member 30 from the openings 10a and 20a. A stopper 16 for stopping at the retracted position, a stopper 17 for stopping the blade member 30 at a position facing the openings 10a and 20a, and the like are provided.
As shown in FIGS. 1 and 3, the back plate 20 has a circular opening 20a for allowing subject light to pass through, an arc-shaped long hole 21 that movably receives a drive pin 103 of the rotor 100 described later, and a screw B. A circular hole 22 for passing through, a circular hole 23 for passing the support shaft 15 and the like are provided. The back plate 20 is connected to the back surface of the base plate 10 with a screw B at a predetermined interval, and cooperates with the base plate 10 to define a blade chamber C in which the blade member 30 is rotatably accommodated. The back plate 20 may be connected to the ground plate 10 by forming a column on the ground plate 10 and welding to the column.

As shown in FIGS. 1, 3, and 4, the blade member 30 includes a circular hole 31 into which the support shaft 15 is inserted, and a long hole 32 into which a driving pin 103 of the rotor 100 described later is inserted.
Then, as the drive pin 103 reciprocates, the blade member 30 is moved away from the openings 10a and 20a as shown in FIG. 8, and at a position facing the openings 10a and 20a as shown in FIG. It is designed to reciprocate between the two.
As the blade member 30, various blade members such as a shutter blade formed of a light-shielding plate, a diaphragm blade or ND filter blade that reduces the amount of light passing therethrough, or a filter blade that cuts infrared light are applied. The

As shown in FIGS. 1, 4, and 5, the rotor 100 includes a through hole 101 through which the support shaft 11 of the base plate 10 passes, a magnetized rotor portion 102 that is formed in a substantially cylindrical shape and is magnetized with different magnetic poles. The drive pin 103 is non-magnetized (not magnetized) so as to rotate integrally with the magnetized rotor portion 102, and projects radially outward from the outer peripheral surface of the magnetized rotor portion 102. A protrusion 104 formed by magnetizing the same magnetic pole as the outer peripheral surface is provided.
The rotor 100 is supported by the base plate 10 so as to be able to turn around a predetermined rotation range (operating angle θ) around the rotation axis L as shown in FIGS. 1 and 6.

The magnetized rotor portion 102 is formed so as to define a cylindrical outer peripheral surface, and the outer peripheral surface is divided into two in the circumferential direction by a surface passing through the rotation axis L, and the N pole outer peripheral surface 102a magnetized to the N pole. The S pole outer peripheral surface 102b is formed to be magnetized to the S pole.
As shown in FIG. 5, the drive pin 103 is formed integrally with the magnetized rotor portion 102 and non-magnetized by a resin material or the like, and has an arm portion 103 a and an arm portion extending in the radial direction of the rotor 100. The pin portion 103b is bent at a right angle from the tip of the pin 103a, and the retaining piece 103c is formed to protrude at a right angle from the tip of the pin portion 103b.
Then, as shown in FIGS. 4, 8, and 9, the drive pin 103 is inserted into the elongated hole 32 of the blade member 30, and exerts the rotational driving force of the rotor 100 on the blade member 30 as the outside. ing.

As shown in FIG. 5, the protruding portion 104 protrudes in the radial direction from the S pole outer peripheral surface 102b of the magnetized rotor portion 102 and is magnetized to the same S pole as the S pole outer peripheral surface 102b.
Further, as shown in FIGS. 5 and 6, the protruding portion 104 protrudes in a cuboid shape in the radial direction from the S pole outer peripheral surface 102 b of the magnetized rotor portion 102, and an end surface 104 a facing the radially outer side and a circumferential direction ( It is formed so as to define two side surfaces 104b and 104c facing the rotation direction of the rotor 100.

As described above, the protrusion 104 is formed so as to protrude from one of the N pole outer peripheral surface 102a and the S pole outer peripheral surface 102b (here, the S pole outer peripheral surface 102b). Since it is only necessary to provide the protrusion 104 on the surface and magnetize the same magnetic pole as the outer peripheral surface, it is possible to easily set the required driving torque and magnetic biasing force while simplifying the structure. it can.
Further, as shown in FIG. 5, the protruding portion 104 is formed so as to protrude in the same direction as the drive pin 103 (the arm portion 103 a thereof) from the S pole outer peripheral surface 102 b so as to be integrally overlapped.
According to this, since the protruding portion 104 and the driving pin 103 (the arm portion 103a thereof) are integrally overlapped with each other, even if the shape protrudes from the outer peripheral surface of the rotor 100, the size reduction can be achieved. , Can increase the mechanical strength.

As shown in FIGS. 1 and 6, the yoke 110 is formed of a flat (plate-like) and substantially U-shaped bend made of a magnetic material that passes the lines of magnetic force. A first magnetic pole portion 111 that defines the first end surface facing portion 111b, a second arc-shaped facing surface 112a on the other end side, a second magnetic pole portion 112 that defines the second end surface facing portion 112b, and a screw B pass through the bent region. The positioning circular hole 113 is provided.
As shown in FIG. 6, the first arcuate opposing surface 111a is formed to face the N pole outer peripheral surface 102a or the S pole outer peripheral surface 102b of the magnetized rotor portion 102 with a predetermined gap.
As shown in FIG. 6, the second arcuate opposing surface 112a is formed to face the N pole outer peripheral surface 102a or the S pole outer peripheral surface 102b of the magnetized rotor portion 102 with a predetermined gap.
As shown in FIG. 6, the first end surface facing portion 111 b is a predetermined gap from the end surface 104 a of the protruding portion 104 of the rotor 100 when the rotor 100 is positioned at the rotation end P <b> 1 on one side of the rotation range (operation angle θ). It bends in a substantially L shape so as to face each other.
As shown in FIG. 6 (indicated by a two-dot chain line), the second end face facing portion 112b is formed when the rotor 100 is positioned at the rotation end P2 on the other side of the rotation range (operation angle θ). It is formed to be bent in a substantially L shape so as to face the end face 104a with a predetermined gap.

That is, the relationship between the rotor 100 and the yoke 110 is such that, as shown in FIG. 6, when the rotor 100 is positioned at the rotation end P <b> 1 on one side of the rotation range, the end surface 104 a of the protrusion 104 is When the rotor 100 is positioned at the rotation end P2 on the other side of the rotation range, the end surface 104a of the protrusion 104 is formed on the second magnetic pole portion 112 of the yoke 110. It faces the second end face facing portion 112b.
As a result, the holding force (magnetic attraction force) when the rotor 100 is positioned at the one rotation end P1 or the other rotation end P2 can be increased, and from the one rotation end P1 to the other side. Rotational torque (magnetic repulsive force) when rotating toward the rotation end P2 or from the rotation end P2 on the other side toward the rotation end P1 on the one side can be increased.

As shown in FIGS. 1, 2, and 4, the coil 120 is wound around a bobbin portion 131 of a holding member 130 described later.
When the coil 120 is energized, it generates magnetic lines of force due to electromagnetic force in the yoke 110, and by switching the energization direction, the N pole and the second magnetic pole part are applied to the first magnetic pole part 111 of the yoke 110. An S pole is generated at 112 or an S pole is generated at the first magnetic pole portion 111 and an N pole is generated at the second magnetic pole portion 112.

The holding member 130 is molded using a resin material, and as shown in FIGS. 1, 2, and 4, a bobbin portion 131 around which the coil 120 is wound, and a flat plate portion 132 that extends from both sides of the bobbin portion 131. The bobbin part 131 is provided with a fitting hole 133 for fitting and fixing the yoke 110 and a circular hole 134 through which the screw B is passed.
The holding member 130 is configured to wind and hold the coil 120 around the bobbin portion 131 and to hold the yoke 110 fitted in the fitting hole 133. Further, the holding member 130 is fixed to the base plate 10 using the screws B in a state where the yoke 110 and the coil 120 are held. The holding member 130 may be fixed to the base plate 10 by forming a column penetrating the circular hole 134 with respect to the base plate 10 and welding the protruding portion of this column to the upper surface of the flat plate portion 132.

The operation of the electromagnetic actuator M configured as described above and the operation of the camera blade driving device will be described with reference to FIGS.
First, in a state where the coil 120 is not energized, as shown in FIG. 7A, when the rotor 100 is positioned at the rotation end P1 in the clockwise direction (one side of the rotation range), the magnetic poles of the magnetized rotor portion 102 The boundary line is at a position shifted from the intermediate position between each of the first arcuate facing surface 111a and the second arcuate facing surface 112a, and the end surface 104a of the protruding portion 104 faces the first endface facing portion 111b. Therefore, between the S pole outer peripheral surface 102b and the first arcuate opposing surface 111a of the first magnetic pole part 111, between the N pole outer peripheral surface 102a and the second arcuate opposing surface 112a of the second magnetic pole part 112, Magnetic attraction force is generated between the end surface 104a of the protruding portion 104 and the first end surface facing portion 111b of the first magnetic pole portion 111, and the rotor 100 is moved to the clockwise rotation end P1 (the blade member 30 is a stopper). 106 Is determined by the by) positioned is surely held.
In this state, in the camera blade driving device, the blade member 30 is in contact with the stopper 16 and positioned at the retracted position (open position) retracted from the openings 10a and 20a as shown in FIG. Correspond.

In this state, when the coil 120 is energized in a predetermined direction, an S pole is generated in the first magnetic pole portion 111 and an N pole is generated in the second magnetic pole portion 112, as shown in FIG.
Thereby, between the S pole outer peripheral surface 102b and the first arcuate opposing surface 111a of the first magnetic pole portion 111, between the N pole outer peripheral surface 102a and the second arcuate opposing surface 112a of the second magnetic pole portion 112, and A repulsive force is generated between the end surface 104a of the projecting portion 104 and the first end surface facing portion 111b of the first magnetic pole portion 111, and the rotor 100 starts to rotate counterclockwise.

  When the rotor 100 rotates counterclockwise, the intermediate position of the rotation range (operating angle θ) is between the end surface 104a of the protruding portion 104 and the first end surface facing portion 111b of the first magnetic pole portion 111. The generated repulsive force acts greatly, and when the intermediate position is passed, the attractive force generated between the end surface 104a of the protruding portion 104 and the second end surface facing portion 112b of the second magnetic pole portion 112 acts greatly, and the rotor 100 The rotation continues while maintaining a stable rotational force. As shown in FIG. 7C, the boundary lines of the magnetic poles of the magnetized rotor portion 102 are the first arcuate facing surface 111a and the second arcuate facing surface 112a, respectively. In a state of being deviated from the intermediate position, the rotation is positioned and stopped at the counterclockwise rotation end P2 (by positioning the blade member 30 in contact with the stopper 107).

In this state, when the energization of the coil 120 is cut off, as shown in FIG. 7D, the outer periphery of the S pole is between the end surface 104a of the protruding portion 104 and the second end surface facing portion 112b of the second magnetic pole portion 112. Magnetic attraction force is generated between the surface 102b and the second arcuate opposing surface 112a of the second magnetic pole part 112, and between the N pole outer peripheral surface 102a and the first arcuate opposing surface 111a of the first magnetic pole part 111, respectively. As a result, the rotor 100 is securely held at the counterclockwise rotation end P2.
This state corresponds to a state in which the blade member 30 is positioned at a position (closed position) facing the opening 10a, 20a in the camera blade drive device as shown in FIG. .

On the other hand, when the coil 120 is energized in the opposite direction, opposite magnetic poles are generated in the first magnetic pole part 111 and the second magnetic pole part 112, respectively, and the rotor 100 rotates counterclockwise as shown in FIG. Following the reverse path from the state located at the end P2, it stably rotates clockwise, and is positioned and held at the clockwise rotation end P1 shown in FIG. 7 (a).
At this time, in the blade driving device for a camera, the blade member 30 is retracted from the openings 10a and 20a as shown in FIG. 8 from the position facing the openings 10a and 20a (closed position) as shown in FIG. Move to (open position) and position.

  In this manner, the rotor 100 is provided with the protruding portion 104 magnetized to the same magnetic pole as the S pole outer peripheral surface 102b, and the first end surface facing portion 111b facing the end surface 104a of the protruding portion 104 with respect to the yoke 110, and By providing the second end surface facing portion 112b, an efficient magnetic circuit can be formed between the rotor 100 and the yoke 110, and a desired driving torque and magnetic biasing force (magnetic force) can be achieved while achieving downsizing. (Attractive attractive force, magnetic repulsive force) and the like can be ensured, and the holding force for holding the rotor 100 at the rotation ends P1 and P2 can be enhanced, and the speed of the rotor 100 can be increased. Further, when this electromagnetic actuator M is used as a drive source of a camera blade drive device, the blade member 30 can be driven smoothly and stably.

FIGS. 10 (a), 10 (b) and 11 show another embodiment of the electromagnetic actuator according to the present invention, which is the same as the above-described embodiment except that the yoke is partially changed. The same reference numerals are assigned to the configurations of and the description thereof is omitted.
In this electromagnetic actuator M, as shown in FIGS. 10 (a), 10 (b) and 11, a yoke 110 ′ is divided into two that can be joined, a first yoke 110a having a first magnetic pole portion 111, and a first yoke 110a. The second yoke 110b having two magnetic pole portions 112 is formed.

As shown in FIGS. 10A and 10B, the first yoke 110a includes a first magnetic pole portion 111 that defines a first arcuate facing surface 111a and a first end surface facing portion 111b, and the thickness of the entire yoke 110 ′. A joining piece 114a having a plate thickness W1 formed to be thinner than W is provided.
As shown in FIGS. 10A and 10B, the second yoke 110b includes a second magnetic pole portion 112 that defines a second arcuate facing surface 112a and a second end surface facing portion 112b, and the overall thickness of the yoke 110 ′. A joining piece 114b having a plate thickness W2 formed in a thin plate shape than W is provided.
The joining pieces 114a and 114b are thinner than the thickness W of the yoke 110 ′ (the first magnetic pole part 111 and the second magnetic pole part 112) so that the first yoke 110a and the second yoke 110b are overlapped and joined to each other. Is formed. Specifically, the thickness W1 of the joining piece 114a and the thickness W2 of the joining piece 114b are respectively formed to be half or less than the thickness W of the yoke 110 ′. That is, it is formed so as to have a relationship of W1 + W2 ≦ W.

As shown in FIG. 11, the yoke 110 ′ is fitted to the fitting hole 133 of the holding member 130 so that the joining piece 114 a and the joining piece 114 b are overlapped with each other, and fixed to the holding member 130. Is done.
Thus, since the first yoke 110a and the second yoke 110b can be joined by superimposing the joining pieces 114a and 114b, the area of the magnetic path can be sufficiently secured and formed integrally. Similar to the yoke, it can be formed with the same thickness.
Further, even if the yoke 110 ′ is substantially U-shaped and the tip side of the first magnetic pole part 111 or the second magnetic pole part 112 is bent, for example, in an L-shape, the yoke 110 ′ is divided into the first yoke 110 a and the second yoke 110 b. Therefore, it can be easily inserted and fixed in the fitting hole 133 of the holding member 130 (such as the fitting hole 133 formed inside the bobbin 131 around which the coil 120 is wound). improves.

12A and 12B show still another embodiment of the electromagnetic actuator according to the present invention, and are the same as the embodiment shown in FIG. 6 except that the yoke is partially changed. The same components are denoted by the same reference numerals and the description thereof is omitted.
In this electromagnetic actuator M, as shown in FIGS. 12A and 12B, the yoke 210 defines a first arcuate facing surface 111 a and a first side facing portion 111 c in the first magnetic pole portion 111, and The two magnetic pole portions 112 are formed so as to demarcate the second arcuate facing surface 112a and the second end surface facing portion 112b.
The first side surface facing portion 111c is formed to face the side surface 104b facing the circumferential direction of the protruding portion 104 with a predetermined gap when the rotor 100 is positioned at one rotation end P1 of the rotation range. .

  According to the electromagnetic actuator M, when the rotor 100 is positioned at the rotation end P1 on one side of the rotation range, the first side surface facing portion in which the side surface 104b of the protrusion 104 is formed on the first magnetic pole portion 111 of the yoke 210. Since it is opposed to 111c, the holding force (magnetic attraction force) when the rotor 100 is located at the one rotation end P1 and the rotation when rotating from the one rotation end P1 toward the rotation end P2 on the other side. The torque can be increased, and when the rotor 100 is positioned at the rotation end P2 on the other side of the rotation range, the end surface 104a of the protruding portion 104 is formed on the second magnetic pole portion 112 of the yoke 210. Since it faces the facing portion 112b, the holding force (magnetic attraction force) when the rotor 100 is positioned at the other rotation end P2 and the rotation from the rotation end P2 on the other side toward the rotation end P1 on one side are rotated. The rotational torque at the time of can be increased.

13 and 14 show still another embodiment of the electromagnetic actuator according to the present invention, and are the same as the embodiment shown in FIG. 6 except that the yoke is partially changed. Are given the same reference numerals and their description is omitted.
In this electromagnetic actuator M, as shown in FIG. 13, the yoke 310 defines a first arcuate facing surface 111 a, a first end surface facing portion 111 b, and a first side surface facing portion 111 c in the first magnetic pole portion 111, Further, the second magnetic pole portion 112 is formed so as to demarcate a second arcuate facing surface 112a, a second end surface facing portion 112b, and a second side surface facing portion 112c.
The first side surface facing portion 111c is formed to face the side surface 104b facing the circumferential direction of the protruding portion 104 with a predetermined gap when the rotor 100 is positioned at one rotation end P1 of the rotation range. .
The second side surface facing portion 112c is formed to face the side surface 104c facing the circumferential direction of the protruding portion 104 with a predetermined gap when the rotor 100 is positioned at the rotation end P2 on the other side of the rotation range. .

When the rotor 100 is positioned at the rotation end P1 on one side of the rotation range, the end surface 104a of the protruding portion 104 faces the first end surface facing portion 111b formed on the first magnetic pole portion 111 of the yoke 310 and protrudes. The side surface 104 b of the portion 104 is opposed to the first side surface facing portion 111 c of the yoke 310.
Therefore, the holding force (magnetic attraction force) when the rotor 100 is positioned at the one rotation end P1 can be increased, and the rotor 100 rotates from the one rotation end P1 toward the other rotation end P2. Rotational torque can be increased.
Further, when the rotor 100 is positioned at the rotation end P2 on the other side of the rotation range, the end surface 104a of the protruding portion 104 is opposed to the second end surface facing portion 112b formed on the second magnetic pole portion 112 of the yoke 310 and protrudes. The side surface 104 c of the portion 104 is opposed to the second side surface facing portion 112 c formed on the second magnetic pole portion 112 of the yoke 310.
Therefore, it is possible to increase the holding force (magnetic attraction force) when the rotor 100 is positioned at the other rotation end P2, and to rotate from the other rotation end P2 toward the one rotation end P1. Rotational torque can be increased.

The operation of the electromagnetic actuator M will be described with reference to FIG. 14. First, in a state where the coil 120 is not energized, as shown in FIG. The boundary line of the magnetic poles of the magnetized rotor portion 102 is at a position shifted from the intermediate position of each of the first arcuate opposing surface 111a and the second arcuate opposing surface 112a, and is projected Since the end surface 104a of the portion 104 faces the first end surface facing portion 111b and the side surface 104b of the protruding portion 104 faces the first side surface facing portion 111c, the S pole outer peripheral surface 102b and the first magnetic pole portion 111 first Between the arc-shaped facing surface 111a, between the N pole outer peripheral surface 102a and the second arc-shaped facing surface 112a of the second magnetic pole portion 112, and between the end surface 104a of the protruding portion 104 and the first end surface facing portion of the first magnetic pole portion 111. 111 Further, a magnetic attractive force is generated between the side surface 104b of the projecting portion 104 and the first side surface facing portion 111c of the first magnetic pole portion 111, and the rotor 100 is moved to the clockwise rotation end P1 (the blade member 30). Is positioned in contact with the stopper 16 and is held securely.
In this state, in the camera blade driving device, the blade member 30 is in contact with the stopper 16 and positioned at the retracted position (open position) retracted from the openings 10a and 20a as shown in FIG. Correspond.

In this state, when the coil 120 is energized in a predetermined direction, an S pole is generated in the first magnetic pole portion 111 and an N pole is generated in the second magnetic pole portion 112 as shown in FIG.
Thereby, it protrudes between the S pole outer peripheral surface 102b and the first arcuate opposing surface 111a of the first magnetic pole portion 111, and between the N pole outer peripheral surface 102a and the second arcuate opposing surface 112a of the second magnetic pole portion 112. Electromagnetic force between the end surface 104a of the portion 104 and the first end surface facing portion 111b of the first magnetic pole portion 111, and between the side surface 104b of the protruding portion 104 and the first side surface facing portion 111c of the first magnetic pole portion 111, respectively. As a result, the rotor 100 starts to rotate counterclockwise.

  When the rotor 100 rotates counterclockwise, the intermediate position of the rotation range (operating angle θ) is between the end surface 104a of the protruding portion 104 and the first end surface facing portion 111b of the first magnetic pole portion 111. The generated repulsive force acts greatly, and when the intermediate position is passed, the attractive force generated between the end surface 104a of the protruding portion 104 and the second end surface facing portion 112b of the second magnetic pole portion 112 acts greatly, and the rotor 100 The rotation continues while maintaining a stable rotational force, and as shown in FIG. 14C, the boundary lines of the magnetic poles of the magnetized rotor portion 102 are respectively the first arcuate facing surface 111a and the second arcuate facing surface 112a. In a state of being deviated from the intermediate position, the rotation is positioned and stopped at the counterclockwise rotation end P2 (by positioning the blade member 30 in contact with the stopper 17).

In this state, when the energization of the coil 120 is cut off, as shown in FIG. 14D, the outer periphery of the S pole is between the end surface 104a of the protruding portion 104 and the second end surface facing portion 112b of the second magnetic pole portion 112. Between the surface 102b and the second arcuate opposing surface 112a of the second magnetic pole part 112, between the N pole outer peripheral surface 102a and the first arcuate opposing surface 111a of the first magnetic pole part 111, and the side surface 104c of the protrusion 104. And the second magnetic pole portion 112 and the second side surface facing portion 112c are each magnetically attracted, and the rotor 100 is securely held at the counterclockwise rotation end P2.
This state corresponds to a state in which the blade member 30 is positioned at a position (closed position) facing the opening 10a, 20a in the camera blade drive device as shown in FIG. .

On the other hand, when the coil 120 is energized in the reverse direction, opposite magnetic poles are generated in the first magnetic pole part 111 and the second magnetic pole part 112, respectively, and the rotor 100 rotates counterclockwise as shown in FIG. Following the reverse path from the state located at the end P2, it stably rotates clockwise, and is positioned and held at the clockwise rotation end P1 shown in FIG.
At this time, in the blade drive device for a camera, the blade member 30 is retracted from the openings 10a and 20a as shown in FIG. 8 from the position facing the openings 10a and 20a (closed position) as shown in FIG. Positioned by moving to the position (open position).

  In this manner, the rotor 100 is provided with the protruding portion 104 magnetized to the same magnetic pole as the S pole outer peripheral surface 102b, and the first end surface facing portion 111b facing the end surface 104a of the protruding portion 104 with respect to the yoke 310, and By providing the second end surface facing portion 112b and the first side surface facing portion 111c and the second side surface facing portion 112c facing the side surfaces 104b and 104c of the protruding portion 104, an efficient magnetic circuit between the rotor 100 and the yoke 310 is provided. The desired driving torque, magnetic biasing force (magnetic attractive force, magnetic repulsive force), etc. can be ensured while achieving miniaturization, and the rotor 100 can be rotated at the rotation ends P1, P2. It is possible to achieve a higher holding force and a higher speed of the rotor 100. Further, when this electromagnetic actuator M is used as a drive source of a camera blade drive device, the blade member 30 can be driven smoothly and stably.

15A and 15B show still another embodiment of the electromagnetic actuator according to the present invention, and are the same as the embodiment shown in FIG. 13 except that the yoke is partially changed. The same components are denoted by the same reference numerals and the description thereof is omitted.
In this electromagnetic actuator M, as shown in FIGS. 15A and 15B, the yoke 410 defines a first arcuate facing surface 111 a and a first side facing portion 111 c in the first magnetic pole portion 111, and The second magnetic pole portion 112 is formed so as to demarcate the second arcuate facing surface 112a, the second end surface facing portion 112b, and the second side surface facing portion 112c.

  According to the electromagnetic actuator M, when the rotor 100 is positioned at the rotation end P1 on one side of the rotation range, the side surface 104b of the protrusion 104 is formed on the first magnetic pole portion 111 of the yoke 410. Since it is opposed to 111c, the holding force (magnetic attraction force) when the rotor 100 is located at the one rotation end P1 and the rotation when rotating from the one rotation end P1 toward the rotation end P2 on the other side. The torque can be increased, and when the rotor 100 is positioned at the rotation end P2 on the other side of the rotation range, the end surface 104a of the protruding portion 104 is formed on the second magnetic pole portion 112 of the yoke 410. The rotor 100 faces the opposite portion 112b, and the side surface 104c of the protrusion 104 faces the second side surface facing portion 112c formed on the second magnetic pole portion 112 of the yoke 410. It is possible to increase the rotation torque when rotating toward the rotating end P1 of the one-side holding force (magnetic attraction force) and the rotation end P2 of the other side when located at the rolling end P2.

16 (a), 16 (b) and 17 (a), 17 (b) show still another embodiment of the electromagnetic actuator according to the present invention. In the yokes 310, 410 shown in the above-mentioned embodiment, FIG. On the other hand, since it is the same as that of above-mentioned embodiment except having applied the rotor 100 'which deform | transformed one part, the same code | symbol is attached | subjected about the same structure and the description is abbreviate | omitted.
In this electromagnetic actuator M, as shown in FIGS. 16A and 17A, the rotor 100 ′ includes a protruding portion 104 that protrudes from an angular position different from that of the drive pin 103.
In this case, it is suitable when the mechanical strength of the drive pin 103 is not so much required, and in particular, since the arrangement of the drive pin 103 can be freely set with respect to the protrusion 104, the arrangement of the electromagnetic actuator M is not limited. The degree of freedom can be increased, and therefore the degree of design freedom of the device can be increased when applied as a drive source for a camera blade drive device.

  In the above embodiment, the camera blade driving device employing the electromagnetic actuator M according to the present invention as a driving source for driving one blade member 30 is shown, but the present invention is not limited to this, and a plurality of blade members is used. The electromagnetic actuator according to the present invention may be employed as a drive source for driving the motor.

  As described above, the electromagnetic actuator of the present invention can generate a desired holding force and driving torque while achieving downsizing, so that it can be applied as a driving source of a camera blade driving device. This is useful as a drive source for other optical equipment or electronic equipment that needs to reciprocate the driven member.

It is a disassembled perspective view which shows the blade drive device for cameras provided with the electromagnetic actuator which concerns on this invention. It is a top view of the blade drive device for cameras shown in FIG. It is a rear view of the blade drive device for cameras shown in FIG. It is sectional drawing of the blade drive device for cameras shown in FIG. It is a perspective view which shows the rotor which makes a part of electromagnetic actuator contained in the blade drive device for cameras shown in FIG. It is a top view which shows the rotor and yoke which make a part of electromagnetic actuator contained in the blade drive device for cameras shown in FIG. (A), (b), (c), (d) is a top view which shows each state for demonstrating operation | movement of the electromagnetic actuator contained in the apparatus shown in FIG. It is a top view for demonstrating operation | movement of the blade drive device for cameras, and shows the state which exists in the retracted position where the blade member retracted from the opening part. It is for demonstrating operation | movement of the blade drive device for cameras, and is a top view which shows the state in which the blade member exists in the position which faces an opening part. FIG. 5 shows another embodiment of the electromagnetic actuator according to the present invention, wherein (a) is a plan view showing a rotor and a yoke, and (b) a side view showing the rotor and the yoke. FIG. 11 is an exploded plan view showing a yoke and a holding member that form part of the electromagnetic actuator shown in FIG. 10. FIG. 5 shows still another embodiment of the electromagnetic actuator according to the present invention, wherein (a) is a plan view showing a rotor and a yoke, and (b) a side view showing the rotor and the yoke. FIG. 10 is a plan view showing a rotor and a yoke, showing still another embodiment of the electromagnetic actuator according to the present invention. (A), (b), (c), (d) is a top view which shows each state for demonstrating operation | movement of the electromagnetic actuator shown in FIG. FIG. 5 shows still another embodiment of the electromagnetic actuator according to the present invention, wherein (a) is a plan view showing a rotor and a yoke, and (b) a side view showing the rotor and the yoke. FIG. 6 shows still another embodiment of the electromagnetic actuator according to the present invention, and (a) and (b) are plan views showing a rotor and a yoke. FIG. 6 shows still another embodiment of the electromagnetic actuator according to the present invention, and (a) and (b) are plan views showing a rotor and a yoke.

Explanation of symbols

10 Ground plane (substrate)
10a opening 11 support shaft 12 through hole 13 recess 14 screw hole 15 support shafts 16, 17 stopper 20 back plate (substrate)
20a opening 21 long holes 22, 23 circular hole 30 blade member 31 circular hole 32 long hole M electromagnetic actuator (drive source)
100, 100 'Rotor P1 Rotation end P2 on one side of the rotation range Rotation end 101 on the other side of the rotation range Through-hole 102 Magnetized rotor portion 102a N pole outer peripheral surface 102b S pole outer peripheral surface 103 Drive pin 103a Arm portion 103b Pin portion 103c Retaining piece 104 Protruding portion 104a End surfaces 104b, 104c Side surfaces 110, 110 ′, 210, 310, 410 Yoke 111 First magnetic pole portion 111a First arc-shaped facing surface 111b First end surface facing portion 111c First side facing portion 112a First 2 arc-shaped facing surface 112b second end face facing portion 112c second side face facing portion 110a first yoke 110b second yoke 113 positioning circular holes 114a, 114b joining piece 120 exciting coil 130 holding member 131 bobbin portion 132 flat plate portion 133 fitting Joint hole 134 Circular hole C Blade chamber B Screw

Claims (6)

A rotor having a cylindrical outer peripheral surface and a drive pin that protrudes in a radial direction from the outer peripheral surface and exerts a driving force to the outside, can rotate within a predetermined rotation range, an excitation coil, and an outer peripheral surface of the rotor An electromagnetic actuator comprising: a yoke having a first magnetic pole part and a second magnetic pole part that define opposing arcuate opposing surfaces and generate different magnetic poles when energized to the coil;
The rotor is disposed so as to have a rotation center in an inner region sandwiched between the first magnetic pole part and the second magnetic pole part of the yoke, demarcates the outer peripheral surface, and is magnetized by different magnetic poles in the circumferential direction. And a projecting portion magnetized to the same magnetic pole as the outer peripheral surface, defining an end surface that protrudes radially from the outer peripheral surface and faces the outer side in the radial direction and a side surface facing the circumferential direction,
The yoke is substantially L-shaped in the first magnetic pole portion or the second magnetic pole portion so as to face an end surface facing the radially outer side of the protruding portion when the rotor is positioned at a rotation end of the rotation range. Having an end face facing portion formed by bending to
An electromagnetic actuator characterized by that. The magnetized rotor portion has an N pole outer peripheral surface and an S pole outer peripheral surface divided into two in the circumferential direction,
The protruding portion is formed to protrude from one of the N pole outer peripheral surface and the S pole outer peripheral surface.
The electromagnetic actuator according to claim 1. The protrusion is integrally formed to protrude from the outer peripheral surface in the same direction as the drive pin.
The electromagnetic actuator according to claim 1, wherein the electromagnetic actuator is characterized in that The yoke includes a side facing portion facing the side surface of the protruding portion when the rotor is positioned at a rotation end of the rotation range in the first magnetic pole portion or the second magnetic pole portion.
The electromagnetic actuator according to any one of claims 1 to 3, wherein The yoke is formed to be bent in a substantially U shape so as to have the first magnetic pole portion on one end side and the second magnetic pole portion on the other end side, and the rotor is a rotation end on one side of the rotation range. A first end surface facing portion formed on the first magnetic pole portion so as to face the end surface of the protruding portion when positioned at the position, and an end surface of the protruding portion when the rotor is positioned at the rotation end on the other side of the rotation range. And a second end face facing portion formed on the second magnetic pole portion to face the
The yoke is formed by a first yoke having the first magnetic pole part and a second yoke having the second magnetic pole part, which are divided into two parts so as to be joined.
The electromagnetic actuator according to any one of claims 1 to 4, wherein the electromagnetic actuator is characterized in that A substrate having an opening through which subject light passes, a blade member movably provided between a position facing the opening and a retracted position retracted from the opening, and a drive source for driving the blade member Prepared,
The drive source is an electromagnetic actuator according to any one of claims 1 to 5,
A blade drive device for a camera.

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