JP3554098B2 - Magnet drive, electromagnetic shutter and camera - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a magnet drive device, an electromagnetic shutter, and a camera in which an armature adsorbed on a fixed yoke is variably supported on a mounting shaft on a drive lever.
[0002]
[Prior art]
As such a magnet drive device, for example, until the armature is attracted and held on the magnetic yoke by the action of an electromagnet or a permanent magnet until the operation state is entered, and the attracting action is released by an electric signal from the attracted state, the drive lever Operates so as to be separated from the yoke integrally with the armature by the action of the spring force, and there is a type in which this operation is used as a mechanical trigger signal.As a main application, in addition to an electromagnetic shutter in a camera, Although various proposals have been made, a magnet drive device in the electromagnetic shutter will be mainly described below.
[0003]
Conventionally, a magnet drive device shown in FIG. 8 is used as an electromagnetic shutter of a camera. In the drawing, reference numeral 1 denotes a yoke formed in a substantially U-shape, which is fixed to a shutter base plate (not shown) by screws 10, and has suction surfaces 1a and 1b formed at the tips. Reference numeral 2 denotes a coil for exciting the yoke 1, which is wound around the yoke 1 via a bobbin 11. Reference numeral 3 denotes a drive lever which is rotatable around the shaft 4. A mounting hole 3 a into which the mounting shaft 7 is loosely fitted is formed at the distal end of the lever portion, and a left-handed driving force is urged by a spring 5. . An armature 6 is formed integrally with the mounting shaft 7. The mounting shaft 7 is mounted between the collar portion 7a and the drive lever 3 with an elastic rubber ring 9 interposed therebetween, and is mounted between the armature 6 and the drive lever 3 so as to house a compression coil spring 8 therein. .
[0004]
The operation of the magnet drive device for an electromagnetic shutter will be described. In the state shown in FIG. 8, the drive lever 3 is turned clockwise from a separation position (not shown) by the setting force accompanying the shutter setting operation, and the armature 6 attracts the yoke 1. This shows a state in which the drive lever 3 is in contact with the surfaces 1 a and 1 b, and the overrun of the drive lever 3 is absorbed by the compression spring 8. In this state, since the yoke 1 is not excited, the armature 6 and the reversing counterclockwise rotation of the drive lever 3 by the spring 5 are mechanically suppressed. Thereafter, when the coil 2 is energized by the operation of the shutter release, the yoke 1 is excited to attract the armature 6. Immediately thereafter, the mechanical restraint acting on the drive lever 3 is released, and the drive lever 3 is turned leftward by the amount of overrun by the action of the spring 5 and the compression spring 8 via the elastic member 9, and the armature 6 and the yoke 1 are moved. The state becomes the suction holding state. Thereafter, when the power supply to the coil 2 is cut off from the suction holding state, the yoke 1 is demagnetized, the suction force is released, and the drive lever 3 is turned leftward by the spring force 5. A left-handed rotation of the drive lever 3 allows a member (not shown) to operate or to operate. Although the description has been made from the excitation to the demagnetization, the same applies to the case where the permanent magnetic force is used. In this case, when the yoke 1 is reversely excited, the drive lever is turned left.
[0005]
[Problems to be solved by the invention]
However, in the above-described configuration, when the shutter blade is operated by turning the drive lever 3 counterclockwise to obtain the shutter time, a precise operation is required. There is no problem if the suction holding / releasing operation always operates in a direction perpendicular to the suction surfaces 1a and 1b (F direction in the drawing), but the drive lever 3 rotates with respect to the shaft 4; The power is acting in the direction F 'in the figure. Therefore, when a machining error or the like occurs in the yoke 1 and the armature 6 and the like, the mounting shaft 7 is loosely fitted in the mounting hole 3a, so that the mounting shaft 7 is loosely fitted. For example, when the armature 6 is in contact with the mounting hole 3a, the armature 6 does not separate from the suction surfaces 1a and 1b at the same time. (The side pressure is large at the position where the shaft comes into contact with the mounting shaft), and the suction holding and releasing operations vary. As for the variation, as the shutter speed becomes faster, the stroke amount increases, and accuracy cannot be guaranteed.
[0006]
As a means for solving these problems, there is a method of positioning and fixing the drive lever 3 and the armature 6 with an elastic adhesive such as a silicon bond. However, work in a suction state is required, and drying of the adhesive is required. Work efficiency is poor.
[0007]
In the means proposed in Japanese Utility Model Publication No. 61-5767, the above-mentioned problem due to the play of the mounting shaft 7 and the mounting hole 3a remains. Further, in recent years, the miniaturization of cameras has been progressing, and the electromagnetic shutter has been required to have a high shutter speed and to be miniaturized.
[0008]
Under such circumstances, if the distance of the center of rotation of the drive lever 3 is shortened and the yoke 1 is arranged from the horizontal to the vertical position in order to reduce the size, the above-mentioned problem is further increased. .
[0009]
An object of a first invention according to the present application is to provide a magnet drive device capable of improving accuracy assurance and reducing the size without increasing the number of parts.
[0010]
Another object of the second invention according to the present application is to provide an electromagnetic shutter having a magnet drive device realizing the object of the first invention.
[0011]
It is an object of a third invention according to the present application to provide a camera having an electromagnetic shutter realizing the object of the second invention.
[0012]
[Means for Solving the Problems]
A first configuration for realizing the object of the first invention according to the present application is a suction member having an armature to be attached to a yoke on one end side, and a suction member that holds the suction member in a tiltable manner and is attached to the yoke. A magnet driving device having a driving member rotatable between a suction position to be separated from the yoke and a separation position separated from the yoke. When the armature moves from the suction position to the separation position, the armature is moved by the driving member. said suction member have a tilting means for tilting inclined posture toward the rotation center side of the to hold, the tilting means includes a flange portion formed in the suction member, facing the flange portion and the An elastic member provided between the driving member and the driving member, the elastic member on the rotation center side of the driving member receiving the separating force of the driving member abuts the collar portion and the driving member, The bullet on the other side In magnet drive apparatus characterized by a member so as to contact with the driving member and the flange portion.
[0014]
A second configuration for realizing the object of the first invention according to the present application is a suction member having an armature that is adsorbed by a yoke on one end side, holding the suction member in a tiltable manner, and adsorbing the yoke. A magnet driving device having a driving member rotatable between a suction position to be separated from the yoke and a separation position separated from the yoke. When the armature moves from the suction position to the separation position, the armature is moved by the driving member. Tilting means for tilting the suction member so as to maintain a tilting posture toward the center of rotation of the suction member, wherein the tilting means allows the collar formed on the suction member to contact the collar. And a contact surface formed on the drive member, and after the collar portion on the rotation center side of the drive member receives the separation force of the drive member and abuts against the contact surface of the drive member. , With the collar on the other side in front Characterized in that so as to abut against the abutment surface of the drive member.
[0015]
In the above configuration, the interval between the collar portion with which the elastic member abuts and the abutment surface of the drive member facing the collar portion is such that the center of rotation of the drive member is narrow and the opposite side is wide. It is characterized by having been formed.
[0016]
In this configuration, the contact surface of the driving member is provided with a height difference between a center side of rotation of the driving member and an opposite side thereof.
[0017]
In this configuration, the contact surface of the drive member is characterized in that the center side of the rotation of the drive member is a flat surface and the opposite side is an inclined surface.
[0018]
In each of the above structures, the yoke is arranged in a vertical position.
[0019]
A configuration for realizing the object of the second invention according to the present application is an electromagnetic shutter characterized in that the above-mentioned magnet driving device is provided in a shutter driving device of a camera.
[0020]
A configuration that achieves the object of the third invention according to the present application is a camera having the above-described electromagnetic shutter.
[0021]
BEST MODE FOR CARRYING OUT THE INVENTION
(1st Embodiment)
1 to 4 show a first embodiment of the present invention.
[0022]
The same members as those shown in the conventional example of FIG. 8 are denoted by the same reference numerals, and the same members indicate the same portions, and the description thereof will not be repeated.
[0023]
FIG. 1 is a diagram showing a magnet driving device of an electromagnetic shutter of a camera to which the present invention can be applied, in which a driving lever 3 is turned clockwise by an urging force of a spring 5 and a yoke 1 and an armature 6 are separated from each other. is there. FIG. 2 is a diagram showing a state in which the drive lever 3 is turned left by the charge lever (not shown) from the state shown in FIG. 1 and the armature 6 is in contact with the yoke 1 during the shutter setting operation. FIG. 3 is a partially enlarged view of the suction surfaces of the armature 6 and the yoke 1 and the mounting shaft 7 in FIGS. 1 and 2, in which the coil 2, the spring 5, and a part of the drive lever 3 are omitted. In the state shown in FIG. 3, the coil 2 is energized from the charge completed state in which the yoke 1 is in the non-excited state and the armature 6 is mechanically prevented from inverting clockwise rotation of the drive lever 3 by the spring 5, and the yoke 1 is turned on. Excites the armature 6 and attracts the armature 6, the mechanical deterrent is released, and the drive lever 3 rotates clockwise by the amount of overrun due to the action of the spring 5 and the compression spring 8, and is attracted by the yoke 1 and the armature 6. This shows a state in which suction and holding are performed. FIG. 4 is a diagram showing a state immediately after the energization to the coil 2 is cut off from the suction holding state in FIG.
[0024]
In the present embodiment, the yoke 1 and the armature 6 are of a type having one suction surface, and the operating portion of the drive lever 3 is such that the armature 6 integral with the mounting shaft 7 that is loosely fitted in the mounting hole 3a is located in the recess 3e. The armature 6 is allowed to tilt with respect to the drive lever 3 to a position where the armature 6 comes into contact with the inner peripheral surface of the concave portion 3e. The first end face 3c and the second end face 3d facing the flange 7a of the mounting shaft 7 are formed as steps having a height difference with the mounting hole 3c as a boundary. Therefore, the mounting shaft 7 is urged together with the armature 6 toward the first end face 3c and the second end face 3d by the spring force of the compression coil spring 9, but at this time, the first end face 3c and the second end face 1e, the elastic rubber ring 9 is sandwiched between the flange portion 7a of the mounting shaft 7 and the higher first end surface 3c in the separated state of the drive lever 3 shown in FIG. The drive lever 3 is supported in an inclined position facing the shaft 4 which is the center of rotation.
[0025]
The operation of the present embodiment will be described below.
[0026]
When the drive lever is turned counterclockwise in the setting direction from the state shown in FIG. 1, the armature 6 held in an inclined state makes one contact with the suction surface 1a of the yoke 1 as shown in FIG. When the lever 3 is turned counterclockwise by a charge lever (not shown), the drive lever 3 overruns, and the integral armature 6 and the mounting shaft 7 rotate in the direction of the arrow 11 in the figure with the one end 6a of the armature 6 as a fulcrum. Then, the armature 6 is set on the suction surface 1a of the yoke 1 as shown in FIG.
[0027]
When set in this manner, the suction shaft body in which the armature 6 and the mounting shaft 7 are integrally formed is set to play back toward the rotation center side of the drive lever 3, and the relationship between the mounting shaft 7 and the mounting hole 3a is In addition, the gap 12 is always generated without the outer portion contacting the center of the mounting shaft 7. The gap always occurs because, as shown in FIG. 4, when the drive lever 3 rotates, the end 3b of the mounting hole 3a does not abut against the mounting shaft 7 to apply a side pressure. Here, when the first end face 3c and the second end face 3d of the drive lever 3 are flat and have no level difference, the play of the mounting shaft 7 and the mounting hole 3a is uneven (the suction shaft body swings right and left due to the play). In this case, the gap 12 is eliminated, and the mounting shaft 7 and the mounting hole 3d come into contact with each other. As a result, the end 3b of the mounting hole 3 applies the side pressure to the mounting shaft 7 first when the drive lever 3 rotates. Therefore, an appropriate separation timing from the suction surface 1a cannot be obtained. Further, when the energization of the coil 2 is cut off and the drive lever 3 is rotated clockwise by the spring force of the spring 5, the first end face 3c and the second end face of the drive lever 3 as shown in FIG. 3d, the two arc portions 9a, 9b of the elastic rubber ring 9 and the mounting shaft flange portion 7a are in contact with each other in that the arc portion 9b of the elastic member 9 on the rotation center side of the drive lever 3 has the first end surface 3c. Then, the pressure applied to the arc portion 9a of the elastic member 9 becomes approximately 9b> 9a, and the separating force to the suction surface 1a is applied in the direction F substantially orthogonal to the suction surface, and the stable separation is performed. Timing is obtained.
[0028]
In the case of 9b <9a, similarly to the above-described generation of the side pressure on the mounting shaft 7 at the end 3b of the mounting hole 3, the same is applied in the direction of the separating force F ′, causing a problem.
[0029]
In the above-described embodiment, since the position of the drive lever 3 is less affected by the position of the coil 2 and the like than in the conventional example of FIG. 8 , the drive lever 3 can be brought closer to the yoke 1 side, The turning radius of the lever 3 can be shortened, and the yoke 1 is also arranged in a horizontal position to a vertical position, which is effective in reducing the size of the shutter driving device. Further, it is possible to eliminate variations in separation timing. Achieving high-speed shutter time can be achieved.
[0030]
The end surface of the drive lever 3 facing the flange portion 7a of the mounting shaft 7 may be a flat surface, and the flange 7a of the mounting shaft 7 may have the same step as the first end surface 3c and the second end surface 3d. Similar effects can be obtained.
[0031]
(Second embodiment )
FIG. 5 shows a second embodiment.
[0032]
In the above-described first embodiment, the cross-sectional shapes of the two arc portions 9a and 9b of the elastic rubber ring 9 are the same, and a step is provided between the first end face 3c and the second end face 3d of the drive lever 3 to thereby provide a step. When the drive lever 3 is separated, the pressure applied to one of the arc portions 9b is made larger than the pressure applied to the other arc portion 9a, and the armature 6 is moved in the axial direction without generating any side pressure on the drive lever 3. However, in the second embodiment, the end surface of the drive lever 3 facing the flange portion 7a of the mounting shaft 7 is a flat surface with no step, and the flange portion 7a of the mounting shaft 7 and the drive lever One half portion 13b (corresponding to the arc portion 9b in the first embodiment) and the other half portion 13a (corresponding to the arc portion 9a in the first embodiment) of the elastic member 13 disposed between the end portion 3 and the end surface of the elastic member 13. To) and the diameter of the piece The portion 13b is made larger than the other half 13a.
[0033]
Therefore, in the present embodiment, when the drive lever 3 separates, the armature 6 is different from that of the first embodiment by the one half portion 13b of the large-diameter elastic member 13 located on the shaft 4 side forming the rotation axis of the drive lever 3. Similarly, the drive lever 3 can be smoothly operated without being inclined, generating no side pressure, and without causing variation in separation timing.
[0034]
(Third embodiment)
FIG. 6 shows a third embodiment.
[0035]
In this embodiment, the flange 7a of the mounting shaft 7 has a flat surface, the diameter of the elastic member 9 disposed between the flange 7a and the driving lever 3 is uniform over the entire circumference, and the mounting hole 3a is a boundary. The end face 3f that is in contact with the elastic member 9 outside the shaft 4 is formed as an inclined surface, and the armature 6 is tilted when the drive lever 3 separates, as in the first and second embodiments.
[0036]
Here, in the present embodiment, since the end face 3f of the inclined surface for tilting the armature 6 is formed, the action of the inclined surface causes the collar portion 7a to move in the direction in contact with the end surface 3f. Is not necessary.
[0037]
Further, the end surface of the drive lever 3 which comes into contact with the elastic member 9 may be flat, and an inclined surface may be provided on the side of the flange portion 7a of the mounting shaft 7. Further, an outer portion of the elastic member 9 (a part farther than the shaft 4). An inclined surface may be provided on the elastic member).
[0038]
(Fourth embodiment)
FIG. 7 shows a fourth embodiment.
[0039]
FIG. 7 is an exploded perspective view of an electromagnetic shutter to which the electromagnetic driving device of each of the above-described embodiments is attached, and a front plate and a front curtain attached to a focal plane shutter main body 20 having a front curtain and a rear curtain (not shown). The yoke 1 for the rear curtain is mounted in the up and down direction (up and down direction of the camera to which the shutter is mounted), and the drive lever 3 is connected to the axes of the operating members 22 and 23 having the shaft portions in the direction orthogonal to the axial direction of the yoke 1. Attached to the part.
[0040]
Each of the above embodiments shows an example in which the yoke is placed in the vertical position. However, the yoke may be placed in the horizontal position, and the suction surface may be changed from one surface to two surfaces.
[0041]
Further, the electromagnetic driving device is not limited to the electromagnetic shutter of the camera described in each of the above embodiments.
[0042]
【The invention's effect】
According to the first aspect of the present invention, when the driving member rotates in the separating direction, the suction member integrated with the armature tilts in a tangential direction with respect to the trajectory of the rotation. Alternatively, when the suction member is released from the suction holding state, the side pressure and the load of the drive lever on the suction member caused by the variation in the position of the suction member are eliminated, and the drive member can be smoothly separated.
[0043]
In addition, it is possible to guarantee an inexpensive, consistent, highly accurate suction holding and separating action without increasing the number of parts, and to achieve a reduction in size.
[0044]
Furthermore, since ideal suction holding and separating actions can be obtained without being affected by processing errors and assembly errors of the yoke and the armature, energy for excitation is minimized, and a battery is used as a power supply. In this case, the battery life can be extended.
[0045]
According to the invention according to claims 2 , 3 , 4, and 5 , the tilting means can be formed with a simple configuration.
[0046]
According to the invention according to claim 6 , the size can be further reduced.
[0047]
According to the seventh and eighth aspects of the invention, it is possible to realize a high-precision, high-speed shutter time.
[Brief description of the drawings]
FIG. 1 is a plan view showing a first embodiment of the present invention and showing a separated state of a drive lever.
FIG. 2 is a diagram showing a state in which the armature according to the first embodiment is attracted to a yoke.
FIG. 3 is an enlarged view of an armature and a yoke according to the first embodiment.
FIG. 4 is a diagram showing a state immediately after the energization is cut off from the suction holding state in FIG. 3;
FIG. 5 is a plan view showing a second embodiment.
FIG. 6 is a diagram showing a third embodiment.
FIG. 7 is an exploded perspective view of an electromagnetic shutter according to a fourth embodiment.
FIG. 8 is a plan view of a conventional magnet drive device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Yoke 2 ... Coil 3 ... Drive lever 5 ... Spring 6 ... Armature 7 ... Mounting shaft 8 ... Compression coil spring 9, 13 ... Elastic member

Claims (8)

An adsorption member having an armature adsorbed on the yoke on one end side, and the adsorption member is held so as to be tiltable, and can be rotated between an adsorption position adsorbing on the yoke and a separation position separating from the yoke. And a driving member having:
When the armature is moved to the separate position from the suction position, have a tilting means for tilting the suction member so as to retain the tilted position of the armature is toward the rotation center side of the drive member,
The tilting unit has a collar formed on the suction member, and an elastic member provided between the driving member facing the collar, and the driving unit receives a separating force of the driving member to drive the driving member. The magnet , wherein after the elastic member on the rotation center side of the member abuts against the collar portion and the driving member, the opposite elastic member abuts on the collar portion and the driving member. Drive. An adsorption member having an armature adsorbed on the yoke on one end side, and the adsorption member is held so as to be tiltable, and can be rotated between an adsorption position adsorbing on the yoke and a separation position separating from the yoke. And a driving member having:
When the armature moves from the suction position to the separation position, the armature includes a tilting unit that tilts the suction member so as to maintain a tilted posture toward the rotation center side of the driving member,
The tilting means has a collar formed on the suction member, and a contact surface formed on the drive member with which the collar can contact, and receives the separating force of the drive member to drive the drive member. After the collar portion on the rotation center side of the member contacts the contact surface of the driving member, the opposite flange portion is contacted with the contact surface of the driving member. Magnet drive. In Claim 1 , the space | interval of the said collar part which the said elastic member abuts, and the contact surface of the said drive member which opposes this collar part narrows the center side of rotation of the said drive member, and widens the opposite side. A magnet drive device characterized by being formed. 4. The magnet drive device according to claim 3 , wherein the contact surface of the drive member has a height difference between a center side of rotation of the drive member and an opposite side. 4. The magnet drive device according to claim 3 , wherein the contact surface of the drive member has a flat surface at the center of rotation of the drive member and an inclined surface at the opposite side. 5. The magnet drive device according to any one of claims 1 to 5 , wherein the yoke is arranged in a vertical position. Electromagnetic shutter, characterized in that it comprises a camera shutter drive unit magnet driving device according to any one of claims 1 to 6. A camera comprising the electromagnetic shutter according to claim 7 .

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