JP2017017436A - Electronic apparatus, electronic apparatus control method, and system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic apparatus, an electronic apparatus control method, and a system which simply and effectively reduces an impact on driving means.SOLUTION: A lens barrel comprises: focus driving means 10 comprising a diaphragm 11 moved so as to drive a fifth lens unit 5, and friction force giving means (a pressure spring 12, a friction plate 14) for giving friction force to the diaphragm 11 in a direction of moving the diaphragm 11; and a control board which controls focus driving means 10 which changes the position of the diaphragm 11 in disconnection of a power source, in accordance with whether a camera device and the lens barrel are attached or not.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electronic device and a control method and system for the electronic device.

  Patent Document 1 discloses a vibrating body having a piezoelectric element, a moving body that is moved by the vibrating body, a holding member that holds the moving body, a moving body shaft that is attached to the holding member, a moving body shaft, and a holding member. A piezoelectric element actuator having a movable bearing movable on one axis side to be fixed has been proposed.

JP 2013-150442 A

  Patent Document 1 can mitigate the impact at the time of dropping by moving the movable bearing and can prevent the vibration body from being destroyed, but is effective only in one direction of dropping, and in other directions of dropping. Is not effective. The lens barrel that can be attached to and detached from the camera body is not limited in the direction of dropping with the lens barrel alone, and when falling, either the end attached to the camera body or the end on the subject side comes first to the floor or ground. (Hereinafter simply referred to as “the ground”) is not determined as to whether or not it will receive an impact. On the other hand, when the lens barrel is attached to the camera body and transported via the strap provided on the camera body, the lens barrel is always on the lower side of the camera body due to the effect of moment, so when it falls, the subject The side edge comes into contact with the ground and receives an impact ahead of the camera body. In addition, due to recent demands for miniaturization, it is required to implement countermeasures against impacts with a small configuration.

  An object of the present invention is to provide an electronic device, a method for controlling the electronic device, and a system that can easily and effectively reduce the impact received by the driving means.

  The electronic device of the present invention is an electronic device that can be attached to and detached from an external device, and includes a moving body, a driving member that is moved to drive the moving body, and the driving member in a direction in which the driving member is moved. And a driving unit including a frictional force applying unit that applies a frictional force to the driving unit, and the driving unit is configured to change a position of the driving member when the power is turned off in accordance with an attachment / detachment state of the electronic device and the external device Control means for controlling the means.

  ADVANTAGE OF THE INVENTION According to this invention, the control method and system of an electronic device which can reduce the impact which a drive means receives easily and effectively can be provided.

It is a partial expanded sectional view of the lens barrel of the embodiment of the present invention. FIG. 2 is an external perspective view of a camera system having the lens barrel shown in FIG. 1. It is sectional drawing of the lens-barrel shown in FIG. It is a flowchart which shows the focusing operation | movement of the camera system shown in FIG. 3 is a flowchart showing an operation when the power of the camera device shown in FIG. 2 is turned off. It is a flowchart which shows operation | movement when removing a lens-barrel from the camera apparatus shown in FIG. It is an expanded sectional view which shows the direction of the force which acts when the lens barrel shown in FIG. 1 falls.

  FIG. 2 is a perspective view of the camera system. The camera system includes a lens barrel (first electronic device) 100 and a camera device (second electronic device) 200. The camera device 200 is a single-lens reflex camera or a non-reflex camera (mirrorless camera). The lens barrel 100 of this embodiment is detachable from the camera device 200 that is an external device. An imaging device applicable to the camera device 200 may be a digital still camera, a digital video camera, a television camera, or the like. The first electronic device of the present embodiment is not limited to the lens barrel, and includes a moving body and a driving unit. The driving unit is a driving member that is moved to drive the moving body, and a driving member. It is only necessary to include frictional force applying means for applying a frictional force to the drive member in the direction in which the motor is moved.

  The lens barrel (unit) 100 includes a photographing optical system, lens control means, manual focus detection means, focus drive means, manual focus ring MFR, manual magnification ring MZR, and focus selection switch FSW.

  The photographing optical system forms a subject image, and includes a zoom lens for zooming (magnifying lens), a focus lens for focus adjustment, a diaphragm for adjusting the amount of light, and the like. The zoom lens is moved in the optical axis direction to change the focal length. The focus lens is a moving body that is moved in the optical axis direction. The in-focus driving means of the present embodiment is a driving means for driving the focus lens and includes a piezoelectric element actuator.

  The driving means for moving the moving body such as a lens is a friction plate using a method of converting the rotational motion of the motor into a linear motion, or a friction plate coupled to the moving body and having a piezoelectric element and a friction plate abutting on the vibration body. A plurality of methods such as a method of moving the vibrating body can be used. Among these, the latter method is called a direct-acting type, and other direct-acting driving means include those using a solenoid. The direct drive means is excellent in driving speed and stopping accuracy, but it is necessary to provide a structure that limits the moving range of the driving member such as the diaphragm, and it is easy to increase the size. There is a possibility that the drive member collides with the restriction structure and the unit including the drive member is damaged. For this reason, it is important to realize miniaturization and impact resistance.

  The lens control means controls each part of the lens barrel 100 and is constituted by a microcomputer. When the manual focus ring MFR is rotated by the user, the manual focus detection means detects the rotation direction and the rotation amount. The lens control means drives and controls the focus drive means based on the detection result by the manual focus detection means to move the focus lens, thereby realizing manual focus adjustment by the user. The manual zoom ring MZR moves the zoom lens when rotated by the user, and realizes the zooming of the means by the user. The focus selection switch FSW is a slide type switch, and selects whether the focus operation is performed by operating the release switch RSW or the manual focus ring MFR.

  The camera device 200 includes camera control means, a release switch RSW, an image sensor, and a connection switch CSW.

  The camera control means controls each part of the camera system and is constituted by a microcomputer. The camera control means communicates with the lens control means to transmit / receive various data. The camera control means calculates the drive amount of the diaphragm in response to half-pressing of the release switch RSW (SW1 ON), drives the diaphragm, and performs automatic focus adjustment (AF). The camera control means can execute phase difference AF and contrast AF. In phase difference AF, focus detection is performed by detecting a phase difference between image signals of a pair of subject images. In contrast AF, focus detection is performed by detecting the peak position of the contrast of the subject image formed by the image sensor while performing a scan that changes the relative position between the focus position formed by the imaging optical system and the image sensor. The camera control means drives a shutter drive circuit (not shown) in response to full depression of the release switch RSW (SW2 ON), guides the photographing light flux to the image sensor, and performs exposure (photographing).

  The image sensor photoelectrically converts the subject image formed by the photographing optical system. When the connection switch CSW is pressed by the user, the detection means (not shown) notifies the camera control means. In response to this, the camera control means transmits a signal indicating that an operation of removing the lens barrel 100 from the camera device 200 has been performed to the lens control means. When the lens control unit is ready to remove the lens barrel 100 from the camera device 200 by controlling the position of the diaphragm 11 to be described later, the lens control unit transmits a signal indicating that to the camera control unit. In response to this, the camera control unit releases the lock that fixes the connection between the lens barrel 100 and the camera device 200, and thus the user can remove the lens barrel 100 from the camera device 200.

  FIG. 3 is a cross-sectional view of a surface including the optical axis α of the lens barrel 100. A mount 100 </ b> A is connectable to the camera device 200.

  Reference numeral 1 denotes a first lens unit that is arranged on the most object side, is held by the rectilinear cylinder 8, and moves integrally in the optical axis direction during zooming by the rotation of the cam cylinder 7. Reference numeral 2 denotes a second lens unit including a fixing portion that is held and fixed to the guide tube 6. Reference numeral 3 denotes a third lens unit that includes a holding portion that is held by the guide cylinder 6 and moves in the optical axis direction upon zooming by rotation of the cam cylinder 7. 4 is a fourth lens that includes a holding portion that is held by the guide tube 6 and moves in the optical axis direction upon zooming by the rotation of the cam tube 7 and holds the fifth lens unit 5 and the focusing drive means 10. Is a unit. Reference numeral 5 denotes a fifth lens unit that is electrically moved in the optical axis direction during the focusing operation. The first lens unit 1, the third lens unit 3, and the fourth lens unit 4 function as a zoom lens, and the fifth lens unit 5 functions as a focus lens.

  The guide tube 6 includes a rectilinear groove 6A that is a groove that is in contact with a cam follower (not shown) provided in each lens unit and serves as a guide for the lens unit to linearly move in the optical axis direction. The cam cylinder 7 is provided with a cam groove 7A having an arbitrary locus connected to a cam follower (not shown) provided in each lens unit, and the cam groove locus and a rectilinear groove 6A provided in the guide cylinder 6 by rotating. In response to this, the lens is moved to a predetermined position.

  The rectilinear cylinder 8 is coupled to the first lens unit 1, includes a holding portion that is held by the guide cylinder 6, and moves in the optical axis direction by the rotation of the cam cylinder 7. The fixed cylinder 9 is coupled to a coupling mechanism (not shown) that is connected to the camera device 200. The fixed cylinder 9 is provided with a manual focusing ring MFR and a manual zooming ring MZR that are rotatable.

  Reference numeral 10 denotes focusing drive means held by the fourth lens unit 4. The focusing driving means 10 is connected to the fifth lens unit 5 by a connecting mechanism (not shown), and the focusing driving means 10 operates to move the fifth lens unit 5 in parallel with the optical axis α and The lens unit 4 is displaced relative to the four lens units 4. The focus driving means 10 is electrically connected to a control board 20 that functions as a lens control means, and the fifth lens unit 5 is moved to a predetermined position in the optical axis direction by operating a release switch RSW or a manual focus ring MFR. Move to.

  The control board 20 functions as a lens control unit and is electrically connected to the camera device 200. The control board 20 supplies electric power to the focusing driving unit 10 and controls the driving direction and driving amount of the focusing driving unit 10 to detect each operation of the lens barrel 100 and perform communication control. The control board 20 also has a function of controlling driving of a driving unit that drives a lens unit as a moving body and moving the moving body to a target position.

  FIG. 1 is an enlarged cross-sectional view of the focusing drive means 10. The focusing drive means 10 includes a vibration plate 11, a pressure spring 12, a spring holder 13, a friction plate 14, and a base holder 15.

  The vibration plate 11 includes a piezoelectric element 11A and moves on the friction plate 14 in parallel with the optical axis α using the piezoelectric effect. The fifth lens unit 5 is connected to the diaphragm 11 by a connecting member (not shown), and the movement of the diaphragm 11 is transmitted to the fifth lens unit 5, whereby the fifth lens unit 5 is moved. . That is, the diaphragm 11 is a drive member that is moved so as to drive the fifth lens unit 5. The piezoelectric element 11A gives a piezoelectric effect to the diaphragm 11 and is connected to the control board 20 by a cable (not shown).

  The pressure spring 12 presses the diaphragm 11 toward the friction plate 14. The spring holder 13 transmits the urging force of the pressure spring 12 to the diaphragm 11. The friction plate 14 is a pedestal for the diaphragm 11 to be pressed by the pressing spring 12 and to move parallel to the optical axis α. The pressure spring 12 and the friction plate 14 function as a friction force applying unit that applies a friction force to the vibration plate 11 in the direction in which the vibration plate 11 is moved.

  The base holder 15 holds the movable holder 19 and the friction plate 14, guides the moving direction of the movable holder 19, and regulates the range of the moving direction. Reference numeral 15 </ b> A denotes an optical close end that is an end on the close side of a range in which the optical performance is ensured in the moving range of the diaphragm 11, and the position is indicated by a broken line. Reference numeral 15B denotes an optical infinite end which is an end on the infinite side of a range in which the optical performance is ensured in the moving range of the diaphragm 11, and the position is indicated by a broken line. The range of the optically close end 15A and the optical infinite end 15B is determined by the control of the control board 20. Reference numeral 15 </ b> C denotes a mechanical closest end that physically restricts the moving range on the closest side in the moving range of the diaphragm 11, and the position is indicated by a broken line. 15D is a mechanical infinite end that physically restricts the moving range on the infinite side of the moving range of the diaphragm 11, and the position is indicated by a broken line. The range of the mechanical close end 15 </ b> C and the mechanical infinite end 15 </ b> D is determined by the shape of the base holder 15. The base holder 15 is held by the fourth lens unit 4.

  Reference numeral 16 denotes a scale that is attached to the fifth lens unit 5 and has position information detected by the position sensor 17. A position sensor (position detection means) 17 is attached to the fourth lens unit 4 and detects information on the scale 16. The position sensor 17 is electrically connected to the control board 20, and the control board 20 detects the position of the fifth lens unit 5 based on the detection result of the position sensor 17. Reference numeral 18 denotes a diaphragm holding member that holds the diaphragm 11. Reference numeral 19 denotes a movable holder configured to hold the diaphragm holding member 18, the spring holder 13, and the pressure spring 12 and be movable with respect to the friction plate 14.

  FIG. 4 is a flowchart for explaining the focusing operation of the camera system, and “S” represents a step. The flowchart shown in FIG. 4 can be embodied as a program for causing a computer to execute the operation of each step, and the program can be stored in a non-transitory computer-readable storage medium. This is also true for other flowcharts.

  First, when a power switch (not shown) of the camera device 200 is turned on in S101, power is supplied to the camera device 200 and the lens barrel 100 from a battery (not shown) built in the camera device 200 in S102. The At this time, the lens barrel 100 and the camera apparatus 200 communicate with each other about the connection state and the mutual identification information.

  Next, in S103, based on the detection result of the position sensor 17, the control board 20 acquires the position information of the fifth lens unit 5, and transmits this information to the camera control means. At this time, the diaphragm 11 (or the movable holder 19) is at an arbitrary position within the range from the mechanical closest end 15C to the mechanical infinite end 15D.

  Next, in S104, the control board 20 determines whether or not the focus selection switch FSW has selected manual operation. If the focus selection switch FSW has selected manual operation (YES in S104), in S105, the user performs a rotation operation of the manual focus ring MFR. Next, in S106, a manual focus detection unit (not shown) detects the rotation direction and the rotation amount.

  Next, in step S107, the control board 20 outputs a movement command (control signal) for the driving direction and the movement amount for moving the fifth lens unit 5 based on the detection result by the manual focus detection unit. 10 to send.

  Next, in S108, based on the command, the diaphragm 11 and the fifth lens unit 5 connected thereto move to a predetermined position. As a result, the diaphragm 11 and the fifth lens unit 5 move in the optical axis direction based on the operation of the manual focusing ring MFR.

  In S109, the camera control means determines whether or not the target in-focus position has been obtained. When the camera control means determines that the target in-focus position has been obtained, the in-focus operation is terminated, and then the SW2 of the release switch RSW is turned on to perform shooting. If the camera control means determines that the target in-focus position has not been obtained, it returns to S104.

  When the focus selection switch FSW selects the electric operation (NO in S104), AF by half pressing the release switch RSW becomes possible. When the release switch RSW is half-pressed in S110, the control board 20 acquires information on the current position of the fifth lens unit 5 based on the detection result of the position sensor 17 in S111, and sends it to the camera control means. Send. Based on this position, the camera control means acquires information relating to the distance to the in-focus position, transmits this distance information to the control board 20, and the flow proceeds to S107. At this time, the operation of the manual focusing ring MFR is invalidated by the control board 20, and the diaphragm 11 does not move by the operation.

  FIG. 5 is a flowchart showing the operation when the power is turned off.

  First, when the user turns off a power switch (not shown) of the camera device 200 in S201, the control board 20 determines the position information of the fifth lens unit 5 based on the detection result of the position sensor 17 in S202. To get. Next, in S203, the control board 20 is a distance from the current position of the fifth lens unit 5 to the position of the fifth lens unit 5 when the diaphragm 11 is closest to the mechanical closest end 15C. Get information.

  Next, in S204, the control board 20 drives the difference in distance from the current position of the fifth lens unit 5 to the position of the fifth lens unit 5 when the diaphragm 11 is positioned at the mechanical close end 15C. The movement command is output to the focusing drive means 10. Next, in S205, the diaphragm 11 moves to a position closest to the mechanical closest end 15C, and the fifth lens unit 5 connected to the focusing driving means 10 also moves the same distance as the moving distance of the diaphragm 11. To do. Next, in S206, the power supply of the camera apparatus 200 is turned off and the supply of power is stopped.

  In this embodiment, in S205, the diaphragm 11 is moved to a position closest to the mechanical close end 15C. However, in the present invention, the vibration plate 11 may be slightly shifted from the position closest to the mechanical close end 15C. Allow. The deviation is, for example, within 1% of the movement range.

  In FIG. 5, when the power is turned off, the diaphragm 11 is moved to a position closest to the mechanical close end 15 </ b> C, but the same operation is performed even when a signal indicating the sleep state is generated in S <b> 201. Also good. The sleep state is a power saving state that is shifted to when the camera system is not operated for a predetermined time.

  FIG. 6 is a flowchart showing an operation when the lens barrel 100 is removed from the camera device 200.

  First, in step S <b> 301, when the user operates the connection switch CSW of the camera device 200, the control board 20 acquires the operation information through communication with the camera device 200. Next, in S <b> 302, the control board 20 acquires information on the position of the fifth lens unit 5 based on the detection result of the position sensor 17. Next, in step S <b> 303, the control board 20 acquires distance information from the current position of the fifth lens unit 5 to the center position of the movement range of the focusing drive unit 10.

  The moving range of the diaphragm 11 (or the movable holder 19) is a range between the mechanical close end 15C and the mechanical infinite end 15D, and the central position of the moving range is between the mechanical close end 15C and the mechanical infinite end 15D. The center position. The case where the diaphragm 11 is at the center position of the moving range is when the center of gravity position of the diaphragm 11 coincides with the center positions of the mechanical close end 15C and the mechanical infinite end 15D.

  Next, in step S <b> 304, the control board 20 outputs a movement command for driving a difference in distance from the current position of the fifth lens unit 5 to the center position of the movement range to the focusing drive unit 10. In S <b> 305, the diaphragm 11 moves to the center position of the movement range, and the fifth lens unit 5 connected to the diaphragm 11 moves the same distance as the movement distance of the diaphragm 11. Next, in S306, the supply of power to the lens barrel 100 is stopped.

  In this embodiment, in S305, the diaphragm 11 is moved to the center position between the mechanical close end 15C and the mechanical infinite end 15D. However, in the present invention, the diaphragm 11 is slightly shifted from the center position of the moving range. It is also acceptable. The deviation is, for example, within 1% of the movement range.

  FIG. 7 is an enlarged cross-sectional view showing the force acting on the focusing drive means 10 when the lens barrel 100 is not connected to the camera device 200, falls in the direction of the optical axis, which is the direction of gravity, and collides with the wall surface. It is. In the focusing driving means 10 that has moved to the center of the moving range, the urging force F <b> 1 by the pressure spring 12 acts on the diaphragm 11 toward the friction plate 14. In addition, an inertial force F2 that works in the falling direction and a frictional force F3 that works in the direction opposite to the dropping direction are applied.

  The urging force F1 is determined by the elastic force of the pressure spring 12. The inertial force F2 is determined by the weight of the fifth lens unit 5, the weight of the focusing drive means 10, the height of dropping, and the like. The frictional force F3 is determined by the inertial force F2, the urging force of the pressure spring 12, and the friction coefficient between the vibration plate 11 and the friction plate 14.

  When the diaphragm 11 (or the movable holder 19) is located closest to the mechanical infinite end 15D, the impact of the drop is directly transmitted to the mechanical closest end 15C and the diaphragm 11. In the present embodiment, when the lens barrel 100 is a single body, the frictional force F3 is applied in the direction opposite to the impact by moving the diaphragm 11 to the center of the moving range. As a result, the inertial force F2 due to the impact can be attenuated with respect to both the moving direction of the diaphragm 11, that is, the drop impact in two directions.

  When the power source of the camera apparatus 200 to which the lens barrel 100 is connected is turned off, the diaphragm 11 is moved to a position closest to the mechanical closest end 15C. The position closest to the mechanical closest end 15 </ b> C is the position closest to the camera device 200 in the movement range of the diaphragm 11. In a state where the camera apparatus 200 and the lens barrel 100 are connected, the user usually carries a strap (not shown) attached to the camera apparatus 200 over his shoulder. In this state, since the moment of the lens barrel 100 is applied to the camera device 200, the lens barrel 100 is positioned below the camera device 200, and when the camera device 200 to which the lens barrel 100 is connected drops, the lens barrel. 100 hits the floor (ground) first and receives an impact. However, according to the present embodiment, since the diaphragm 11 has moved to the position closest to the mechanical close end 15C, the impact can be effectively reduced by the friction force F3 acting in the direction opposite to the dropping direction. it can.

  According to the present embodiment, the diaphragm 11 is always urged toward the friction plate 14, and when the diaphragm 11 moves, a brake due to friction is always applied, and the diaphragm 11 falls in either direction of the optical axis direction. Even the brake effect works. When the lens barrel 100 is dropped together with the camera device 200, the diaphragm 11 is in the position closest to the mechanical closest end 15C, so that the braking force can be applied for a long time.

  In the present embodiment, the control board 20 (or lens control means) of the lens barrel 100 changes the position of the diaphragm 11 when the power is turned off according to the attachment / detachment state of the lens barrel 100 and the camera device 200. Thus, it has a function of controlling the focusing drive means. However, the camera control means of the camera device 200 may have this function. Such a control method also constitutes one aspect of the present invention.

  In the present embodiment, when the lens barrel 100 is transported together with the camera device 200 to which the lens barrel 100 is attached, the user carries a strap (not shown) provided on the camera device 200 over his / her shoulder. However, when the first electronic device is transported with the second electronic device to which the first electronic device is attached, it is not known which is the power point of transport. Therefore, when the first electronic device is transported together with the second electronic device to which the first electronic device is attached, when the first electronic device is located below the second electronic device in the direction of gravity, the control means is The diaphragm 11 is disposed at a position closest to the second electronic device. In addition, when the first electronic device is transported together with the second electronic device to which the first electronic device is attached, the control means is a diaphragm if the second electronic device is positioned above the gravitational direction. 11 is arranged at a position farthest from the second electronic device. Thereby, the impact can be alleviated by making maximum use of the frictional force acting on the diaphragm 11 when dropped.

  As mentioned above, although embodiment of this invention was described, a various deformation | transformation and change are possible for this invention within the range of the summary.

  The electronic device of the present invention can be applied to a lens barrel, a camera device, and the like.

  DESCRIPTION OF SYMBOLS 11 ... Diaphragm (drive member), 20 ... Control board (control means), 100 ... Lens barrel (unit, 1st electronic device), 200 ... Camera apparatus (external device, 2nd electronic device)

Claims (12)

An electronic device detachable from an external device,
A moving object,
A drive unit comprising: a drive member that is moved so as to drive the movable body; and a frictional force applying unit that applies a frictional force to the drive member in a direction in which the drive member is moved.
Control means for controlling the drive means so as to change the position of the drive member when the power is turned off according to the attachment / detachment state between the electronic device and the external device;
An electronic device comprising:   2. The control means, wherein the drive member is arranged at the center of a movement range of the drive member in response to a signal indicating that an operation of removing the electronic device from the external device has been performed. The electronic device as described in. When the electronic device is transported together with the external device to which the electronic device is attached, the electronic device is located below the gravitational direction with respect to the external device,
In the state where the electronic device is attached to the external device, the control means moves the driving member in a moving range of the driving member in accordance with a signal indicating that an operation to turn off the power is performed. The electronic apparatus according to claim 1, wherein the electronic apparatus is disposed at a position closest to the external device. When the electronic device is transported together with the external device to which the electronic device is attached, the electronic device is positioned above the external device in the direction of gravity,
In the state where the electronic device is attached to the external device, the control means moves the driving member in a moving range of the driving member in accordance with a signal indicating that an operation to turn off the power is performed. The electronic apparatus according to claim 1, wherein the electronic apparatus is disposed at a position farthest from the external device. When the electronic device is transported together with the external device to which the electronic device is attached, the electronic device is located below the gravitational direction with respect to the external device,
In a state where the electronic device is attached to the external device, the control unit moves the drive member to a position closest to the external device in the movement range of the drive member in accordance with a signal indicating that the electronic device is in a sleep state. The electronic apparatus according to claim 1, wherein the electronic apparatus is disposed on the electronic apparatus. When the electronic device is transported together with the external device to which the electronic device is attached, the electronic device is positioned above the external device in the direction of gravity,
In the state where the electronic device is attached to the external device, the control means moves the drive member farthest from the external device in the movement range of the drive member in response to a signal indicating a sleep state. The electronic device according to claim 1, wherein the electronic device is disposed at a position.   The electronic device according to claim 1, wherein the driving unit is a piezoelectric element actuator.   The electronic apparatus according to claim 1, wherein the electronic apparatus is a lens barrel. An electronic device in which a unit having a moving body and driving means is detachable,
The drive means includes a drive member that is moved so as to drive the movable body, and a friction force applying means that applies a friction force to the drive member in a direction in which the drive member is moved.
The electronic apparatus includes a control unit that controls the driving unit so as to change a position of the driving member when the power is turned off according to an attachment / detachment state of the electronic device and the unit. machine.   The electronic apparatus according to claim 9, wherein the electronic apparatus is an imaging apparatus. A method of controlling an electronic device that can be attached to and detached from an external device,
The electronic device is
A moving object,
A drive unit comprising: a drive member that is moved so as to drive the movable body; and a frictional force applying unit that applies a frictional force to the drive member in a direction in which the drive member is moved.
Have
A method for controlling an electronic device, comprising: controlling the driving unit so as to change a position of the driving member when the power is turned off in accordance with an attachment / detachment state between the electronic device and the external device. A system comprising a first electronic device and a second electronic device to which the first electronic device is detachable,
The first electronic device includes:
A moving object,
Drive means comprising: a drive member that is moved so as to drive the movable body; and a friction force applying means that applies a friction force to the drive member in a direction in which the drive member is moved.
Have
The first electronic device or the second electronic device changes the position of the driving member when the power is turned off according to the attachment / detachment state of the first electronic device and the second electronic device. And a control means for controlling the driving means.