JP2006010723A - Switching mechanism and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To thin and miniaturize a switching mechanism, and to hold the position of a rotating body at non-energizing time at one switching position. <P>SOLUTION: The switching mechanism is equipped with arm parts 132A and 132B provided on both sides with respect to the center of rotation of the rotating body 132; a 1st shape memory alloy member 104 attached to the arm part 132A on one side, with respect to the center of rotation and giving stronger tensile force, by energizing than at the non-energizing time, a 2nd shape memory alloy member 105 attached to the arm part 132B on the other side, with respect to the center of rotation and giving stronger tensile force by energizing than at the non-energizing time, and a control means for controlling the energizing of the respective 1st and 2nd shape memory alloy members 104 and 105 for controlling the tensile force to one arm part 132A and the other arm part 132B. Then, the tensile force at non-energizing time of the 2nd shape memory alloy member 105 is set stronger than the tensile force at the non-energizing time of the 1st shape memory alloy member 104. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a switching mechanism that switches positions by energization of a shape memory alloy member and an electronic apparatus using the switching mechanism.

  There is a drive mechanism having a drive body that is operated in conjunction with the rotation of a yoke (rotating body), for example, a video camera having an iris mechanism. An example of a conventional iris mechanism provided in such a video camera is shown in FIGS. The iris mechanism a slides the diaphragm blades b and c each having a predetermined shape, and adjusts the amount of light by changing the shape of the opening d by the diaphragm blades b and c. The diaphragm blades b and c are formed by integrally forming blade portions e and f and support portions g and h protruding from the blade portions e and f, respectively. j is formed.

  The diaphragm blades b and c are slid by the driving force of the electromagnetic motor k, and the central portion of the rotating arm m functioning as a rotating body is fixed to the motor shaft l of the electromagnetic motor k. Support pins n and o project from both ends of the rotating arm m, and the support pins n and o are inserted into the long holes i and j of the diaphragm blades b and c, respectively. It is supported by the moving arm m. When the electromagnetic motor k is rotated, the rotating arm m is rotated synchronously, and the diaphragm blades b and c are slid in different directions according to the rotating direction of the electromagnetic motor k. The size of the opening d is changed depending on the positional relationship between the diaphragm blades b and c, and the amount of light passing through the opening d is adjusted.

  In the iris mechanism a provided in the above-described conventional video camera, the diaphragm blades b and c are operated by rotating the rotating arm m fixed to the motor shaft l of the electromagnetic motor k. All of the diaphragm blades b and c, the rotating arm m and the electromagnetic motor k, which are components of the iris mechanism a, must be arranged in series in the direction along the optical path OP. There is a problem of becoming. In addition, since the position of the electromagnetic motor k that operates the diaphragm blades b and c is determined with respect to the diaphragm blades b and c, the degree of freedom in designing a video camera having the iris mechanism a is impaired. is there. Therefore, Patent Document 1 discloses a mechanism that uses two shape memory alloy members instead of an electromagnetic motor as a drive source, and adjusts the aperture amount of the diaphragm blades by controlling these pulling forces.

JP 2001-147459 A

  However, in the drive device using the shape memory alloy member, since the rotating member is driven using the mutual pulling force generated by energizing the two shape memory alloy members, for example, when the power is not supplied, When cut, the rotating member is held in a neutral position. If such a mechanism is used for an iris driving device, the diaphragm blades remain open when no power is supplied. As a result, unnecessary light enters the CCD and adversely affects the CCD. Accordingly, an object of the present invention is to prevent the rotating member from being held in a neutral position when no current is applied in the switching mechanism using two shape memory alloy members.

  That is, the present invention is attached to the arm portion provided on both sides with respect to the rotation center of the rotating member and the arm portion on one side with respect to the rotation center, and the one arm portion is not energized to the one side by energization. A first shape memory alloy member that gives a strong pulling force, and a second shape that is attached to the other arm part with respect to the center of rotation and that gives a stronger pulling force to the other arm part when energized than when not energized. A memory alloy member; and control means for controlling energization of each of the first shape memory alloy member and the second shape memory alloy member to control a tensile force applied to one arm portion and the other arm portion. The second shape memory alloy member is a switching mechanism in which the tensile force when the first shape memory alloy member is not energized is stronger than the tensile force when the first shape memory alloy member is not energized. In addition, the electronic device to which the switching mechanism is applied.

  In the present invention, in the switching mechanism that rotates the rotating member by energizing the first shape memory alloy member and the second shape memory alloy member, the tensile force when the second shape memory alloy member is not energized is reduced. Since the first shape memory alloy member is stronger than the non-energized pulling force, the second shape memory alloy member pulling force is superior to the first shape memory alloy member pulling force when de-energized. The rotating member can be held at the position pulled by the second shape memory alloy member.

  Therefore, according to the present invention, the switching mechanism can be reduced in thickness and size, and the position of the rotating member when not energized can be held at one switching position instead of the neutral position. As a result, by using the switching mechanism of the present invention in the iris driving device, the diaphragm blades can be kept closed when no power is supplied, and unnecessary light can be prevented from entering the CCD, resulting in high reliability. An electronic device can be provided.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the accompanying drawings. The embodiment described below is a preferred specific example of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention is particularly limited in the following description. Unless otherwise stated, the present invention is not limited to these forms.

  1 and 2 show a preferred embodiment of an electronic apparatus in which the switching mechanism of the present invention is applied to an iris driving device. 1 and 2, the electronic device is a video camera recorder. The video camera recorder 10 is a digital video camera recorder, for example, and has a body 12, and the body 12 has a video cassette housing portion 14. A video cassette can be detachably loaded in the accommodating portion 14. A lens barrel 18 is accommodated in the upper portion 16 of the body 12. A stereo microphone 20 and a liquid crystal monitor 22 are provided on the upper portion 16. As shown in FIGS. 1 and 2, the liquid crystal monitor 22 can display, for example, a color image being photographed or a color image at the time of reproduction by directing it in a desired direction. A manual focus lens 31 is disposed on the front side of the lens barrel 18, and a color viewfinder 32 is provided on the rear side of the lens barrel 18. In addition, a battery pack 34 is detachably attached to the side of the body 12.

  FIG. 3 shows an example of the internal structure of the lens barrel 18 described above. The lens barrel 18 has, for example, a rectangular parallelepiped shape or a cylindrical shape. The lens barrel 18 includes an objective lens 30, a variable power lens (or variator lens) 40, an iris 110, a focus lens 44, a filter 31, guide bars 62 and 64, and the like. A CCD (charge coupled device) 52 is fixed on the rear side of the lens barrel 18. The CCD 52 is an image light receiving unit that receives an image that has passed through the objective lens 30, the variable magnification lens 40, the iris 110, the filter 31, and the focus lens 44.

  The guide bars 62 and 64 are fixed in parallel with the optical axis OL of the lens barrel 18. A holder 70 of the variable power lens 40 is disposed on the guide bar 62. The holder 70 of the variable power lens 40 is operated along the guide bar 62 during a predetermined stroke by operating the drive unit 72. It is possible to move and position with. The iris 110 is used to reduce the amount of light incident from the objective lens 30, and the iris amount of light can be changed by the operation of the iris driving device 100. The iris 110 is provided, for example, about the optical axis OL at the center of the lens barrel 18. The iris driving device 100 is driven by the control of the control unit 300 according to a command from the computer 400.

  The focus lens 44 is a lens for focusing light from a subject that has passed through the objective lens 30, the variable magnification lens 40, and the iris 110. The focus lens 44 moves along the guide bar 64 by the operation of the drive unit 199. The image received by the CCD 52 can be sent to the computer 400 or displayed on the color viewfinder 32 after predetermined processing is performed by the image processing unit 130. The user confirms the image by looking at the color viewfinder 32.

  4 to 8 show a first preferred embodiment of the iris driving device. 4, 5, and 6, the iris driving device 100 schematically includes a first diaphragm blade 101, a second diaphragm blade 102, a yoke 103, a first shape memory alloy member 104, and a second shape memory alloy member 105. , Fixed portions 106 and 107, and a rotating body 132. The iris 110 has a first diaphragm blade 101 and a second diaphragm blade 102. In FIG. 4, the opening 114 of the iris 110 is shown in an open state, and in FIG. 5, the opening 114 of the iris 110 is shown in a closed state.

  The first diaphragm blade 101 and the second diaphragm blade 102 of the iris 110 are moved relative to each other so that the size of the opening 114 of the iris 110 is continuously changed, thereby passing through the optical axis OL in FIG. The amount of light to be adjusted is adjusted. The first aperture blade 101 has a notch 101A, and the second aperture blade 102 has a notch 102A. The notch 101A and the notch 102A form an opening 114. An L-shaped connecting portion 120 is provided at the end of the first aperture blade 101. Similarly, an L-shaped connecting portion 121 is also provided at one end of the second aperture blade 102. Long holes 120A and 121A are formed in the connecting portions 120 and 121, respectively. The formation direction of these long holes 120A, 121A is the Y direction (horizontal direction in FIG. 4). The first diaphragm blade 101 and the second diaphragm blade 102 are made of metal or plastic.

  Next, a Hall element 164 as a magnetic sensor is disposed in the gap between the yoke 103 and the magnet 130 in FIG. 3, and the Hall element 164 detects a change in magnetic flux due to the rotation of the magnet 130. The shaft (rotating shaft) 504 and the rotating body 132 that are the center of rotation are made of a conductive material (brass, SUS, etc.) and are fixed to each other, and the magnet 130 is also fixed integrally. The rotating body 132 has an arm shape centered on the shaft 504, and an arm portion 132 </ b> A extends on one side and 132 </ b> B extends on the other side of the shaft 504.

  The first shape memory alloy member 104 and the second shape memory alloy member 105 exhibit superelasticity when both are energized and exhibit a function as a tension coil spring. The first shape memory alloy member 104 and the second shape memory alloy member 105 are alloy members made of, for example, Ti (titanium), Ni (nickel), and Cu (copper). However, not limited to this, the first and second shape memory alloy members 104 and 105 may be a binary alloy of Ni and Ti.

  One end portion of the first shape memory alloy member 104 is connected to the pin 140 of one arm portion 132 </ b> A of the rotating body 132. The other end of the first shape memory alloy member 104 is connected to the fixed portion 106. One end of the second shape memory alloy member 105 is connected to the pin 141 of the other arm 132B of the rotating body 132. The other end portion of the second shape memory alloy member 105 is connected to the fixing portion 107. The fixing portions 106 and 107 are fixed to, for example, the lens barrel 18 shown in FIG.

  In the present embodiment, in the first shape memory alloy member 104 and the second shape memory alloy member 105, the tensile force when the second shape memory alloy member 105 is not energized is when the first shape memory alloy member 104 is not energized. The tensile force of the second shape memory alloy member 105 is greater than the tensile force of the first shape memory alloy member 104 when no current is applied, and the arm portion 132B of the rotating body 132 is The shape memory alloy member 105 is pulled so that it can be held at the pulled position.

  Here, in order to make the tensile force of the second shape memory alloy member 105 stronger than the tensile force of the first shape memory alloy member 104 at the time of non-energization, when the wire diameters of the two shape memory alloy members are the same, the winding diameter If the winding diameter is the same, the wire diameter may be increased.

  FIG. 7 shows an example in which the first shape memory alloy member 104 and the second shape memory alloy member 105 described above are electrically connected to the control unit 300. The controller 300 is electrically connected to the other end 104B of the first shape memory alloy member 104 and the other end 105B of the second shape memory alloy member 105 for energization. One end portion 104 </ b> A of the first shape memory alloy member 104 and one end portion 105 </ b> A of the second shape memory alloy member 105 are electrically connected to the control unit 300 through the yoke 103. An intermediate portion of the yoke 103 is electrically connected to the control unit 300. Thereby, the control part 300 can send a required electric current only to one or both with respect to the 1st shape memory alloy member 104 or the 2nd shape memory alloy member 105 by the instruction | indication of the computer 400. FIG.

  FIG. 8 shows the rotation angle detection means 160 for detecting the rotation angle at which the yoke 103 rotates about the central axis C. FIG. 8 includes a hall element 164 as a sensor, a magnet 130, a bobbin 502, and a yoke 103. In the embodiment, the magnet 130 is magnetized substantially parallel to the longitudinal direction of the rotating body 132, and a Hall element 164 is used as a sensor. The hall element 164 is arranged in a direction substantially perpendicular to the line LN that bisects the rotation angle of the magnet 130 and substantially in the center in the direction of the length l of the magnet 130, and is perpendicular to the shaft of the gap caused by the rotation of the magnet 130. It has a structure for detecting a change in magnetic flux in the direction. The bobbin 502 is a member for maintaining the Hall element 164 at a predetermined position and is made of a non-magnetic material. The yoke 103 is made of a ferromagnetic material to form a magnetic path.

  Next, a method for detecting the rotation angle will be described. With the arrangement of the magnet 130, the yoke 103, and the Hall element 164 described above, the output of the Hall element 164 as shown in FIG. 8B can be obtained. This output characteristic shows a sine wave characteristic, and the normal angle θ is 30 degrees or less, and the points A, B, and C in FIG. 8B can be regarded as practically direct. By applying this characteristic, the rotation angle of the rotating body 132 is converted into an electric signal.

  Next, the operation of the iris driving device 100 will be described with reference to FIGS. 4 and 5. FIG. 4 shows an open state in which the opening 114 of the iris 110 is the largest. In order to realize this open state, the control unit 300 in FIG. 7 energizes the first shape memory alloy member 104 with a predetermined amount of current. Thus, the first shape memory alloy member 104 functions as a tension coil spring, and the rotating body 132 is rotated in the R1 direction as shown in FIG. In this case, the second shape memory alloy member 105 is not energized. Accordingly, the first diaphragm blade 101 and the second diaphragm blade 102 are in the most distant state, so that the opening 114 of the iris 110 can be secured most widely.

  Next, when the control unit 300 in FIG. 7 stops energizing the first shape memory alloy member 104 and energizes the second shape memory alloy member 105 with a predetermined amount of current, the controller 300 enters a closed state as shown in FIG. Become. That is, the second shape memory alloy member 105 functions as a tension coil spring, and the rotating body 132 is rotated in the direction of R2. As shown in FIG. 5, the first diaphragm blade 101 moves while being guided by the base 190 along the T1 direction, and the second diaphragm blade 102 moves in the T2 direction. Accordingly, the opening 114 of the iris 110 is the smallest or closed.

  As described above, when the control unit 300 energizes one of the first shape memory alloy member 104 and the second shape memory alloy member 105, the open and closed states of the iris 110 can be realized. However, when the control unit 300 supplies an arbitrary current to the first shape memory alloy member 104 and the second shape memory alloy member 105, the first shape memory alloy member 104 and the second shape memory alloy member 105 By realizing the balance of the rotating body 132 at a certain rotational angle position by the difference in the force of the tension coil springs exerted respectively, it is possible to define an arbitrary rotational angle state in the R1 or R2 direction of the rotating body 132. . As a result, the amount of light can be adjusted by adjusting the degree of opening of the opening 114 of the iris 110.

  Thus, when rotating the rotator 132 to a predetermined position, the position command signal and the electrical signal from the rotation angle detecting means are input to the computer 400, the signal difference is calculated, and the result is output to the control unit 300 to store the shape. A predetermined current is supplied to at least one of the alloy members 104 and 105 to rotate the rotating body 132 to the command position. FIG. 6 shows a cross section of the present embodiment. The rotating body 132 and the magnet 130 are integrally fixed via a shaft 504, and the shaft 504 is urged in one direction by a thrust spring 505 and pressed against the fixed wall 506. The shaft 504 and the thrust spring 505 are electrically connected by the urging force, and the electric circuit shown in FIG. 7 is formed.

  Further, when no current flows through any of the first shape memory alloy member 104 and the second shape memory alloy member 105 (when no current is applied), the tensile force by the second shape memory alloy member 105 is as described above. Thus, the rotating body 132 is pulled, and the opening 114 of the iris 110 as shown in FIG. 5 is held in the smallest or closed state. Thereby, for example, when the power is turned off or when power is not supplied due to some trouble, the opening 114 of the iris 110 is the smallest or closed by the pulling force when the second shape memory alloy member 105 is not energized. Therefore, it is possible to prevent unnecessary light from entering the CCD, and it is possible to reliably achieve protection of the CCD.

  Next, a second embodiment of the iris driving device will be described. In the iris driving device 100 of the second embodiment shown in FIGS. 9 and 10, the first diaphragm blade 101, the second diaphragm blade 102, the rotating body 132, the first shape memory alloy member 104, and the second shape memory alloy member. However, in the second embodiment, the yoke, magnet, and hall element used to detect the rotation angle in the first embodiment are the same as in the first embodiment. It differs in that it is unnecessary.

  That is, in the second embodiment, a yoke, a magnet, and a hall element are not provided at the central portion of the rotating body 132, and arm portions 132A and 132B are provided on both sides around the shaft 504. One end of the first shape memory alloy member 104 is attached to the pin 140 provided on the arm portion 132A, and one end of the second shape memory alloy member 105 is attached to the pin 141 provided on the other arm portion 132B. Yes. Further, the other end portion of the first shape memory alloy member 104 is connected to the fixing portion 106, and the other end portion of the second shape memory alloy member 105 is connected to the fixing portion 107.

  Also in the second embodiment, as in the first embodiment, the tensile force when the second shape memory alloy member 105 is not energized is set stronger than the tensile force when the first shape memory alloy member 104 is not energized. When the power is not supplied, the tensile force of the second shape memory alloy member 105 is greater than the tensile force of the first shape memory alloy member 104, and the arm portion 132B of the rotating body 132 is pulled by the second shape memory alloy member 105. Thus, it can hold | maintain in the position at the time of the pulling.

  The operation of the switching mechanism according to the second embodiment is the same as that of the first embodiment. That is, FIG. 9 shows an open state in which the opening 114 of the iris 110 is the largest. In order to realize this open state, the control unit 300 in FIG. 9 supplies a predetermined amount of current to the first shape memory alloy member 104. Accordingly, the first shape memory alloy member 104 functions as a tension coil spring, and the rotating body 132 is rotated in the R1 direction as shown in FIG. In this case, the second shape memory alloy member 105 is not energized. Accordingly, the first diaphragm blade 101 and the second diaphragm blade 102 are in the most distant state, so that the opening 114 of the iris 110 can be secured most widely.

  Next, when the control unit 300 in FIG. 9 stops energization of the first shape memory alloy member 104 and energizes the second shape memory alloy member 105 with a predetermined amount of current, the controller 300 enters a closed state as shown in FIG. Become. That is, the second shape memory alloy member 105 functions as a tension coil spring, and the rotating body 1329 is rotated in the direction of R2. As shown in FIG. 10, the first diaphragm blade 101 moves while being guided by the base 1190 along the T1 direction, and the second diaphragm blade 102 moves in the T2 direction. Accordingly, the opening 114 of the iris 110 is the smallest or closed.

  As described above, when the control unit 300 energizes one of the first shape memory alloy member 104 and the second shape memory alloy member 105, the open and closed states of the iris 110 can be realized. However, when the control unit 300 supplies an arbitrary current to the first shape memory alloy member 104 and the second shape memory alloy member 105, the first shape memory alloy member 104 and the second shape memory alloy member 105 By realizing the balance of the rotating body 132 at a certain rotational angle position by the difference in the force of the tension coil springs exerted respectively, it is possible to define an arbitrary rotational angle state in the R1 or R2 direction of the rotating body 132. . As a result, the amount of light can be adjusted by adjusting the degree of opening of the opening 114 of the iris 110.

  FIG. 11 shows an example in which the first shape memory alloy member 104 and the second shape memory alloy member 105 described above are electrically connected to the control unit 300. The controller 300 is electrically connected to the other end 104B of the first shape memory alloy member 104 and the other end 105B of the second shape memory alloy member 105 for energization. The controller 300 can pass a necessary current to only one or both of the first shape memory alloy member 104 and the second shape memory alloy member 105. At this time, the iris 110 is opened and closed in advance, and the resistance value (impedance) of each of the first shape memory alloy member 104 and the second shape memory alloy member 105 and the rotation angle at that time are stored in the control unit 300. Thus, the control unit 300 detects the resistance value of each of the first shape memory alloy member 104 and the second shape memory alloy member 105, and controls the rotation angle of the rotation member 132 based on this impedance.

  That is, since the shape memory alloy member has a predetermined relationship between the impedance at the time of energization and the internal temperature of the shape memory alloy (the amount of energization current of the shape memory alloy), using this relationship, The position (rotation angle) stored in the control unit 300 can be grasped, and the rotation angle of the rotation member 132 can be controlled. FIG. 12 shows the relationship between the impedance (conductor resistance) of the shape memory alloy member and the internal temperature (that is, the amount of energization current). FIG. 12 shows changes in conductor resistance values when a shape memory alloy based on Ni, Ti, and Cu ternary (which may of course be a Ni and Ti binary alloy) is energized and the internal temperature is raised and lowered. ing. By increasing the temperature (that is, increasing the energization current), the conductor resistance value decreases (the shape memory alloy at this time is in the martensite phase), and the shape memory alloy transforms into an austenite phase from around 50 ° C. Resistance value increases. In addition, about the influence by ambient temperature, the control part 300 can eliminate an influence by controlling so that the increase / decrease in the impedance of the 1st shape memory alloy member 104 and the 2nd shape memory alloy member 105 may be canceled.

  Thus, if the rotation angle of the rotation member 132 is controlled by the impedance when the first shape memory alloy member 104 and the second shape memory alloy member 105 are energized, a special sensor for detecting the rotation angle of the rotation member becomes unnecessary. It is possible to achieve further miniaturization and simplification of the mechanism.

  By the way, the present invention is not limited to the above embodiment. For example, for the first shape memory alloy member 104 and the second shape memory alloy member 105, in addition to the coil shape, a form as shown in FIG. 13, that is, a fold shape as shown in FIG. A wavy shape as shown in FIG. 13 (B), a partially folded shape as shown in FIG. 13 (C), a partially coiled shape as shown in FIG. 13 (D), other shapes, or A combination of these may also be used.

  Moreover, in this embodiment, although the arm part to which the one end part of the 1st shape memory alloy member 104 and the one end part of the 2nd shape memory alloy member 105 are each attached is provided, this arm part is necessarily arm shape. The first shape memory alloy member 104 and the second shape memory alloy member 105 are only required to be attached at positions away from the shaft that is the center of rotation.

  In the present embodiment, the controller 300 may control the shutter operation using the first aperture blade 101 and the second aperture blade 102 in addition to the normal iris drive. When performing the shutter operation, as shown in FIG. 14, an instantaneously large amount of current is applied as compared with PWM (Pulse Width Modulation) control using a pulse signal in a normal iris function. The amount of current at this time is set to about 1.3 to 1.4 times the amount of current during the normal iris function so as not to cause characteristic destruction of the shape memory alloy member. This makes it possible to have a function as a mechanical shutter along with an iris function.

  Furthermore, in the above-described embodiment, the switching mechanism of the present invention may be applied to other switching mechanisms (for example, a filter switching mechanism and a macro switching mechanism) other than the iris driving device. The present invention is incorporated in a lens barrel of a digital video camera recorder 10, for example. However, the present invention is not limited to this, and other types of electronic devices such as digital still cameras, CCTVs, mobile phones and other lenses are mounted. The present invention can be applied to all electronic devices.

It is a perspective view which shows an example of the electronic device which applied this embodiment to the iris drive device. It is the perspective view which looked at the electronic device of FIG. 1 from another angle. It is sectional drawing which shows an example of the lens-barrel of an electronic device. It is a figure which shows the open state in 1st Embodiment. It is a figure which shows the closed state in 1st Embodiment. It is a side view which has the partial cross section in 1st Embodiment. It is a figure which shows the example of an electrical connection in 1st Embodiment. It is a perspective view which shows the example of an angle detection means. It is a figure which shows the open state in 2nd Embodiment. It is a figure which shows the closed state in 2nd Embodiment. It is a figure which shows the example of an electrical connection in 2nd Embodiment. It is a figure which shows the relationship between the impedance at the time of electricity supply of a shape memory alloy member, and internal temperature. It is a schematic diagram which shows the example of a form of another shape memory alloy member. It is a figure which shows the example of the pulse signal at the time of shutter operation | movement. It is a perspective view which shows the conventional iris drive device. It is a top view which shows the conventional iris drive device.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Video camera recorder (electronic device), 18 ... Lens barrel, 100 ... Iris drive device, 101 ... 1st aperture blade, 102 ... 2nd aperture blade, 103 ... Yoke, 104 ... 1st shape memory alloy member, 105 ... 2nd shape memory alloy member, 132 ... Rotating body, 132A ... Arm part, 132B ... Arm part, 160 ... Rotation angle detection means, 300 ... Control part

Claims (10)

Arm portions provided on both sides with respect to the rotation center of the rotating member;
A first shape memory alloy member attached to an arm portion on one side with respect to the center of rotation and applying a stronger tensile force to the arm portion on the one side by energization than when not energized;
A second shape memory alloy member attached to the other arm portion with respect to the center of rotation and applying a stronger tensile force to the other arm portion than when not energized by energization;
Control means for controlling energization to each of the first shape memory alloy member and the second shape memory alloy member to control a pulling force on the one arm portion and the other arm portion. And
A switching mechanism, wherein the second shape memory alloy member has a tensile force when not energized when the first shape memory alloy member is not energized. The switching mechanism according to claim 1, wherein the control unit controls the amount of current to each of the first shape memory alloy member and the second shape memory alloy member. The control means detects a resistance value when each of the first shape memory alloy member and the second shape memory alloy member is energized, and generates a tensile force with respect to the one arm portion and the other arm portion. The switching mechanism according to claim 1, wherein the switching mechanism is controlled. A diaphragm blade is connected to each of the one arm portion and the other arm portion,
The control means adjusts an opening amount by the diaphragm blades by energization control to the first shape memory alloy member and the second shape memory alloy member,
2. The switching mechanism according to claim 1, wherein an opening amount by the diaphragm blade is minimized by a pulling force of the second shape memory alloy member when the power is not supplied. 5. The switching mechanism according to claim 4, wherein the control unit controls the shutter operation by the diaphragm blades with a larger amount of current than when the aperture amount is controlled by the diaphragm blades. Arm portions provided on both sides with respect to the rotation center of the rotating member;
A first shape memory alloy member attached to an arm portion on one side with respect to the center of rotation and applying a stronger tensile force to the arm portion on the one side by energization than when not energized;
A second shape memory alloy member attached to the other arm portion with respect to the center of rotation and applying a stronger tensile force to the other arm portion than when not energized by energization;
Control means for controlling energization to each of the first shape memory alloy member and the second shape memory alloy member to control a pulling force on the one arm portion and the other arm portion. And
An electronic apparatus comprising: a switching mechanism in which a tensile force when the second shape memory alloy member is not energized is stronger than a tensile force when the first shape memory alloy member is not energized. The electronic device according to claim 6, wherein the control unit controls a current amount to each of the first shape memory alloy member and the second shape memory alloy member. The control means detects a resistance value when each of the first shape memory alloy member and the second shape memory alloy member is energized, and generates a tensile force with respect to the one arm portion and the other arm portion. The electronic device according to claim 6, wherein the electronic device is controlled. A diaphragm blade is connected to each of the one arm portion and the other arm portion,
The control means adjusts an opening amount by the diaphragm blades by energization control to the first shape memory alloy member and the second shape memory alloy member,
The electronic apparatus according to claim 6, wherein an opening amount by the diaphragm blade is minimized by a pulling force of the second shape memory alloy member when the power is not supplied. The electronic device according to claim 9, wherein the control unit controls a shutter operation by the diaphragm blades with a larger amount of current than when the aperture amount is controlled by the diaphragm blades.

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