JP2000287432A - Electromagnetic actuator and sector switch system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to control a rotor in its operational speed easily in an electromagnetic actuator. SOLUTION: A permanent magnet 13a is mounted on a stator 6 on the side of a second face 6h opposite to a first face 6g thereof. The permanent magnet 13a is rotated eccentrically so that the magnetic force of the permanent magnet 13a has an influence on the magnetic pole part 6d of the stator 6. When a coil (L) is fed with electricity and magnetic pole parts 6c and 6d of the stator 6 are magnetized, the magnetic force of the magnetic pole part 6d is adjustable by a relative position of the permanent magnet 13a and the stator 6, and the speed of the rotor 1 in movement can be adjusted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electromagnetic actuator and a sector opening / closing device.

[0002]

2. Description of the Related Art Conventionally, as an electromagnetic actuator used for a sector opening / closing device of a camera, for example, an electromagnetic actuator capable of fine control and having a high response has been required.

As an electromagnetic actuator having such a demand, for example, Japanese Utility Model Application No. 1-97206 (Japanese Utility Model Application Publication No.
No. 9377).
Hereinafter, the disclosed technology will be briefly described with reference to FIG.

[0004] A rotor 101 magnetized in the radial direction and magnetic pole portions 102 to 105 facing the N and S magnetic poles of the rotor 101.
Is provided between the magnetic pole portions 103 and 104 on the stepping motor provided with the stators 106 and 107, and the position of the adjusting auxiliary pole 108 is appropriately changed. Thus, the magnetic relationship between the magnetic poles of the rotor 101 and the magnetic pole portions 102 to 105 of the stator can be appropriately adjusted. Specifically, the rotor 101
The correction of the initial position shift and the starting characteristic error caused by the mounting error of the stators 106 and 107 and the magnetization intensity error of the N and S magnetic poles in the rotor 101 are performed.

[0005]

SUMMARY OF THE INVENTION The adjusting auxiliary pole 108 described above.
The only part that can be adjusted is the correction of the initial position of the rotor 101 and the starting characteristics. That is, with the above-described configuration, it is not possible to adjust the operating speed after the rotor 101 starts. This is because the adjusting auxiliary pole 108 is not magnetically controlled at all. That is, when the rotor 101 starts rotating, its rotation speed is controlled by magnetic fluctuations of the magnetic pole portions 102 to 105 of the stators 106 and 107,
This is because the adjustment auxiliary pole 108, which is not magnetically controlled, is hardly affected.

Therefore, in order to adjust the operating speed of the rotor 101 by the above-described method, it is necessary to control the exciting current to the coil 109 attached to the stators 106 and 107. Therefore, even when the operating speed is slightly different for each step motor, there is a disadvantage that the exciting current for energizing the coil must be finely controlled for each step motor. Even if such an adjustment is made, it is necessary to further finely adjust it in accordance with the characteristics of each step motor.

[0007] In order to increase the speed of the electromagnetic actuator, complicated operations such as controlling the exciting current to the coil 109 are required.

[0008] Such inconvenience naturally arises when the opening and closing of the sector is controlled by an electromagnetic actuator.

[0009]

SUMMARY OF THE INVENTION The present invention provides a rotor having a permanent magnet, a stator having a magnetic pole portion facing a peripheral surface of the rotor, a coil for generating a magnetic pole in the magnetic pole portion of the stator when energized, A drive circuit for energizing the coil in accordance with a predetermined drive signal, and a magnetic force adjusting means for adjusting the magnetic force of the magnetic pole portion at an outer position of the stator. The magnetic force itself can be controlled, and the operating speed as well as the starting characteristics of the rotor can be controlled without changing the drive signal to the coil. Therefore, even when the operating speed of the rotor is slightly different, the problem that the exciting current of the coil must be finely controlled for each electromagnetic actuator can be reduced. Further, when sufficient control cannot be performed even if the exciting current of the coil is delicately controlled for each electromagnetic actuator, further adjustment is possible. Further, the operating speed of the rotor can be increased.

The magnetic force adjusting means includes a magnet, and if the magnetic force of the magnetic pole portion is adjusted by arranging the pole position of the magnet at a desired position, in addition to the above-described effects, for example, the magnetic force adjusting means can be used. It is not necessary to control electrically.

Since the electromagnetic actuator and the sector driven by the electromagnetic actuator are included, even if the operating speed of the sector is slightly different, the exciting current for energizing the coil must be finely controlled for each electromagnetic actuator. Can be reduced.

[0012]

DETAILED DESCRIPTION OF THE INVENTION The invention according to claim 1 of the present application is directed to a rotor having a permanent magnet, a stator having a magnetic pole portion facing the peripheral surface of the rotor, and a magnetic pole formed in the magnetic pole portion of the stator when energized. And a driving circuit for energizing the coil in accordance with a predetermined driving signal, and a magnetic force adjusting means for adjusting the magnetic force of the magnetic pole portion at an outer position of the stator.

In the invention according to claim 2 of the present application, the magnetic force adjusting means includes a magnet, and the magnetic force of the magnetic pole portion is adjusted by arranging the pole position of the magnet at a desired position.

The invention according to claim 3 of the present application includes the electromagnetic actuator according to claim 1 or 2, and a sector driven by the electromagnetic actuator.

[0015]

An embodiment of the present invention will be described below with reference to the drawings. As will be described later, in this embodiment, a step motor is used as an example of the electromagnetic actuator, but the electromagnetic actuator is not limited to this.

FIG. 1 is a configuration diagram of a sector opening / closing device.
In FIG. 1, a rotor 1 has a permanent magnet 2
Has two magnetic poles N and S, and is fixed to the rotor shaft 2.
The rotor shaft 2 is rotatably supported by an upper plate 3 and a middle plate 4 as shown in FIG. A closing lever 5, which will be described later, is fixed to the lower end of the rotor shaft 2 in FIG. FIG. 2 is a sectional view taken along line AA of FIG.

The stator 6 is substantially U-shaped and has two legs 6a and 6b. Magnetic pole portions 6c, 6d are formed at the respective distal ends of the two legs 6a, 6b. These magnetic pole portions 6c, 6d are arranged on a first surface 6g facing the peripheral surface of the rotor 1. I have. Magnetic pole parts 6c, 6d
Are formed with salient pole portions 6e and 6f (magnetic portions) whose gaps with respect to the outer periphery of the rotor 1 are partially narrowed.
e and 6f are arranged at point symmetrical positions with respect to the center of the rotor shaft 2.

A coil L is wound around the leg 6a of the stator 6, and this coil L is
1 is connected to the control circuit 12. Control circuit 1
2 to energize the coil L, a magnetic pole can be generated in the magnetic pole portions 6c and 6d of the stator 6.

The closing lever 5 is press-fitted and fixed to the rotor shaft 2. The closing lever 5 has, at one end, a pin 5a that engages with the holes 7b, 8b of the sectors 7, 8 so as to drive the sectors 7, 8 by reciprocating swinging about the rotor shaft 2. The closing lever 5 has an arm 5b at the other end which comes into contact with an adjustment pin 9 described later when the sectors 7 and 8 are closed.

The sectors 7 and 8 are formed with openings 7a and 8a. The sector 7 is rotatably supported around the rotor shaft 2 at the center of the closing lever 5 so as to operate integrally with the closing lever 5, and a pin 5a at one end of the closing lever 5 is fitted into the hole 7b. (See FIG. 2). The sector 8 is rotatably supported around the pin 4a of the middle plate 4, and the pin 5a of the closing lever 5 is fitted into the long hole 8b and driven by the pin 5a.
As shown in FIG. 2, the sectors 7 and 8 are both a middle plate 4 and a lower plate 1.
0. A pin 4b is implanted in the middle plate 4, and as shown in FIG. 1, when the sector 8 is rotated in the fully open direction by the pin 5a, the sector 8
To restrict further rotation. As shown in FIG. 1, the pin 9 restricts the position of the sectors 7 and 8 in the closing direction by abutting on the arm 5b of the opening / closing lever 5, and as shown in FIG. The portion 9a is press-fitted and fixed to the middle plate 4 so that the portion 9a cannot be rotated unless the torque exceeds a predetermined value. The pin 9 is connected to the arm 5 of the closing lever 5.
b is formed eccentrically with the press-fitting portion 9a. When a pin 9 is rotated by fitting a tool such as a screwdriver into the slit groove 9c, the pin 9b rotates eccentrically. Has become.

A permanent magnet 13a is located outside the stator 6.
And a magnetic force adjusting means 13 including a pin portion 13b. That is, the pin portion 13b is formed eccentrically with the permanent magnet 13a, and the pin portion 13b is press-fitted and fixed in the hole 4c provided in the intermediate plate 4 so that the pin portion 13b cannot be rotated unless the torque is equal to or more than a predetermined value. When a tool such as a driver is fitted to 13c and the permanent magnet 13a is rotated, the permanent magnet 13a rotates eccentrically.

As described above, the permanent magnet 13a is positioned outside the stator 6 (in this embodiment, the second surface facing the first surface 6g).
6h), that is, at a position where the stator 6 is interposed between the permanent magnet 13a and the rotor 1.
By eccentrically rotating 3a, the magnetic force of the permanent magnet 13a can be influenced by the magnetic force of the magnetic pole portion 6d of the stator 6. That is, the S pole or N of the permanent magnet 13a
The magnetic coupling force between the stator 6 and the rotor 1 can be controlled by moving the pole closer to or farther from the magnetic pole portion 6d, or by moving the pole left and right.

Therefore, the coil L is energized and the stator 6
When the magnetic pole portions 6c and 6d are magnetized, the permanent magnet 13
The magnetic force generated by the magnetic pole portion 6d can be adjusted by the relative position of the a and the stator 6, and the so-called starting characteristics and operating speed of the rotor 1 can also be adjusted. That is, the N pole or S pole of the permanent magnet 13a is arranged so as to amplify the magnetic force generated in the magnetic pole part 6d, or conversely, the N pole or S pole of the permanent magnet 13a is reduced so as to reduce the magnetic force generated in the magnetic pole part 6d. By arranging the poles, the operating speed of the rotor 1 can be adjusted. Therefore, the speed of the rotor 1 can be increased, and the rotor 1 can be adjusted to a desired speed. If the above is described with reference to FIG. 5 described later, the times T1 and T3 can be shortened or the length can be adjusted to a desired length.

The control circuit 12 in FIG. 1 determines the energizing time of the coil L based on the luminance information of the subject and the sensitivity information of the film from a photometric unit (not shown), and outputs a drive signal for the rotor 1 to the driver circuit 11. This drive signal supplies the coil L with an output pulse generated by amplification and conversion in the driver circuit 11.

The phase relationship between the rotor 1 and the stator 6, ie, the angle a at which the magnetic poles of the rotor 1 stop as shown in FIG.
b, c, and d are as follows. First, as shown in FIG. 4, a is the magnetic pole position of the rotor 1 and the magnetic pole position of the stator 6 when the coil L is energized in a state where the rotor 1 is not subject to any regulation. b, as shown in the figure, when the coil L is not energized in a state where the rotation of the rotor 1 is not regulated at all, the salient pole portions 6e and 6f of the stator 6
(Not magnetized) and a stop position due to the natural magnetic coupling force of the magnetic poles of the rotor 1. c is a position when the arm 5b of the opening / closing lever 5 is restricted by the adjustment pin 9, as shown in FIG. d is a position when the sector 8 is restricted by the pin 4b as shown in FIG.

If the angles of a, b, c, and d are α between a and a, β between cd and (the full operating angle of the opening / closing lever 5), bc between bc and γ2 between ad, α < 90
゜, α> β, γ1> 0, γ2> 0. Note that γ1 is set in consideration of the adjustment amount by the adjustment pin 9 and the magnetic coupling force between the magnetic pole of the rotor 1 and the salient pole portions 6e and 6f of the stator 6. Further, γ2 is an angle provided in order to ensure that the closing operation is performed with the d set slightly before the fully opened state in the exposure operation.

As shown in FIG. 4, when the open / close lever 5 and the rotor shaft 2 are connected to each other, the open / close lever 5 is moved to a predetermined position while the rotation of the rotor 1 is not regulated at all and the coil L is energized. For example, an index 4c provided on the middle plate 4 so as to be in phase.
To match the direction of the arm 5b of the opening and closing lever 5 to
Alternatively, it is press-fitted and fixed while being positioned by a method using an assembling jig (not shown).

In such a sector opening / closing device, the control circuit 12 determines the energizing time of the coil L as described above by performing a release operation of the camera in the state of FIG. Turn on electricity. Coil L
First, the N pole is applied to the magnetic pole portion 6c of the stator 6,
An S pole is generated in the magnetic pole portion 6d, and the rotor 1 starts rotating clockwise. With this rotation, the sectors 7 and 8 rotate via the pins 5a of the opening and closing lever 5 to start the exposure operation, and after a predetermined time t1, the sectors 7 and 8 are opened by a predetermined amount (see FIG. 5). Immediately, the driver circuit 11 energizes the coil L in the reverse direction, so that the magnetic pole portion 6c of the stator 6 has an S pole,
When an N-pole is generated in the magnetic pole portion 6d, the rotor 1 rapidly reverses. The sectors 7 and 8 return to the original state (FIG. 1) via the pin 5a of the opening / closing lever 5 due to the reverse rotation of the rotor 1, and the exposure operation ends after a predetermined time t2 (see FIG. 5). By setting the energization time t2 for closing the sectors 7 and 8 to be longer than the actual closing operation time of the sectors 7 and 8, the bounds (vibration) of the sectors 7 and 8 and the opening / closing lever 5 and the like at the time of closing are set. ) Can be prevented.

The desired initial position and starting characteristics of the rotor 1 and the desired operating speed are determined by the dimensional errors and assembly errors of the rotor 1, the rotor shaft 2 and the stator 6, the magnetization strength errors of the N and S magnetic poles in the rotor 1, and the like. Are not obtained, and the times T1 and T3 in FIG.
Is different from the predetermined value, the permanent magnet 13a is eccentrically rotated by using a tool such as a screwdriver in the slot 13c,
The magnetic force of the magnetic pole portion 6d of the stator 6 is adjusted. If the problem is solved by this adjustment, the troublesome operation of adjusting the drive signal for the coil can be eliminated. If the desired adjustment cannot be obtained even with the adjustment using the permanent magnet 13a, it goes without saying that the adjustment is performed using the drive signal for the coil. By performing such two types of adjustment, the operating speed of the rotor 1 can be adjusted more precisely than by one type of adjustment. For example, after performing the adjustment by the drive signal for the coil, the adjustment can be performed by the permanent magnet 13a in accordance with the characteristics of each actuator or the sector opening / closing device, and the adjustment can be performed more accurately. Adjustments can be made to portions that cannot be adjusted. That is, when sufficient control cannot be performed even if the exciting current of the coil is delicately controlled, further adjustment is possible.

If the sectors 7 and 8 cannot be operated accurately due to the dimensions and assembly errors of the sector opening / closing parts such as the rotor 1, the rotor shaft 2 and the opening / closing lever 5, the slot 9c of the adjusting pin 9 is screwed. Rotation using a tool such as the above causes the pin portion 9b to eccentrically rotate, thereby changing the distance between the center of rotation of the adjustment pin 9 and the arm portion 5b of the opening / closing lever 5, and thereby the stop position c of the rotor 1 Changes to angles γ1 and β
, The sector operation due to the error shown by the dashed line in FIG. 5 can be easily corrected to the appropriate sector operation shown by the solid line.

In the embodiment, the adjusting pins 9 are provided to adjust the operation of the sectors 7 and 8. However, when the adjusting means is not provided, the adjusting pins 9 need only be eliminated. Does not require any position control means. In other words, when the adjustment pin 9 is eliminated, the position of the rotor when the coil is not energized is the same as in FIG. 4, and r1 = 0. In the embodiment, the opening / closing lever 5 is directly attached to the rotor shaft 2. However, the pinion is attached to the rotor shaft in phase alignment, and the pinion and the opening / closing lever, or a ring member known as a sector opening / closing device mechanism, are attached to the phase. It is good also as composition of the relation which matches.

Further, in the embodiment, when the sectors 7 and 8 are closed, the coil L is energized in the reverse direction. However, when a high speed is not required at the time of closing, the coil L is de-energized when the sector is closed. The sector may be closed only by the natural magnetic coupling force between the rotor and the stator.

In the embodiment, the phase γ2 between the magnetic pole position of the stator when the coil is energized and the magnetic pole position of the rotor 1 when the operation of the sector in the fully open direction is restricted is represented by γ2
> 0, but when the current is not supplied in the reverse direction when closing the sector, the phase γ2 may be set to γ2 = 0.

Further, in the embodiment, as the means for adjusting the position of the permanent magnet 13a, the one in which the pin portion 13b is an eccentric pin is used, but other known position adjusting means may be used.

Further, in the embodiment, as the means for adjusting the stop position of the opening / closing lever 5, an eccentric pin is used as the adjusting pin 9, but other known position adjusting means may be used.

In the above embodiment, the magnetic portion is provided so as to urge the sector to the most closed position when the power is not supplied. However, as in the case of a single-lens reflex camera, the magnetic portion is normally provided in the open position. When configuring, the magnetic part may be arranged so that the sector is at the most open position.

Further, in the above embodiment, an example is shown in which a rotor having a plurality of permanent magnets and a stator in which a plurality of magnetic pole portions are simultaneously magnetized are used, but these can be changed as appropriate.

Further, in the above embodiment, an example is shown in which the present invention is applied to driving of a sector opening / closing device in which a rotor swings at a fixed angle, but the present invention is not limited to this. For example, it is of course possible to apply to a stepping motor in which a rotor rotates.

[0039]

According to the present invention, a rotor having a permanent magnet, a stator having a magnetic pole portion facing the peripheral surface of the rotor, a coil for generating a magnetic pole in the magnetic pole portion of the stator when energized, and A driving circuit for energizing the coil in accordance with a driving signal, and a magnetic force adjusting means for adjusting the magnetic force of the magnetic pole portion at an outer position of the stator. , And the starting characteristics and operating speed of the rotor can be controlled without changing the drive signal to the coil. Further, when sufficient control cannot be performed even if the exciting current of the coil is delicately controlled for each electromagnetic actuator, further adjustment is possible. Further, the speed of the rotor can be increased.

The magnetic force adjusting means includes a magnet, and the magnetic force of the magnetic pole portion is adjusted by arranging the pole position of the magnet at a desired position. It is not necessary to control electrically.

Since the electromagnetic actuator and the sector driven by the electromagnetic actuator are included, even if the operating speed of the sector is slightly different, the exciting current for energizing the coil must be finely controlled for each electromagnetic actuator even if the operating speed of the sector is slightly different. Can be reduced.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG. 1;

FIG. 3 is a configuration diagram of a sector opening / closing device during a shutter release operation of FIG. 1;

FIG. 4 is an explanatory view when an opening / closing lever is attached to a rotor shaft.

FIG. 5 is a time chart of a sector operation and a coil energized state.

FIG. 6 is a configuration diagram of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rotor 6 Stator 6c, 6d Magnetic pole part 7, 8 sector 11 Drive circuit 13 Magnetic force adjusting means 13a Magnet L coil

Claims (3)

[Claims] 1. A rotor having a permanent magnet, a stator having a magnetic pole portion facing the peripheral surface of the rotor, a coil for generating a magnetic pole in the magnetic pole portion of the stator when energized, An electromagnetic actuator, comprising: a driving circuit for energizing a coil; and a magnetic force adjusting means for adjusting a magnetic force of the magnetic pole portion at an outer position of the stator. 2. The magnetic force adjusting means according to claim 1, wherein said magnetic force adjusting means includes a magnet, and adjusts the magnetic force of said magnetic pole portion by arranging a pole position of said magnet at a desired position. Electromagnetic actuator. 3. A sector opening / closing device comprising: the electromagnetic actuator according to claim 1; and a sector driven by the electromagnetic actuator.