Imaging device and interchangeable lens

Abstract

This imaging device comprises a diaphragm mechanism having a plurality of opening / closing blades, a housing that movably supports the plurality of opening / closing blades, and a drive body that moves the plurality of opening / closing blades relative to the housing. A drive motor for applying driving force to the drive body is attached to the housing. The housing is provided with a detection unit which has a detection magnet that is rotated in conjunction with the drive motor and a sensor that detects the rotation angle of a rotor in the drive motor, the detection unit being positioned inside the housing. Thus, because the detection unit is not present on the outside of the diaphragm mechanism, the imaging device can be miniaturized while ensuring a high-efficiency drive state of the drive motor.

Description

Imaging device and interchangeable lens

[0001] The present technology relates to the technical field of an imaging device and an interchangeable lens having an aperture mechanism in which a plurality of opening and closing blades are operated by the driving force of a drive motor.

[0002] Various imaging devices such as video cameras and still cameras, and interchangeable lenses that are detachably attached to these imaging devices, generally have built-in diaphragm mechanisms, also known as irises (see, for example, Patent Document 1). The diaphragm mechanism adjusts the amount of light incident on the imaging element to set the required F-number (aperture value), making it possible to capture images or videos with appropriate brightness.

[0003] In imaging devices and interchangeable lenses that have such aperture mechanisms, there are types in which multiple opening and closing blades are operated (moved) by the driving force of a drive motor (stepping motor), thereby controlling the size of the light-transmitting hole and adjusting the amount of light incident on the imaging element.

[0004] On the other hand, some imaging devices and interchangeable lenses in which multiple opening and closing blades are operated by the driving force of a drive motor are configured to drive the drive motor using advance angle control. Advance angle control is a control for driving the drive motor with high efficiency by maintaining the rotor angle phase and the excitation phase at 90 degrees.

[0005] In imaging devices and interchangeable lenses that perform such advance angle control, it is necessary to detect the rotation angle (rotation position) of the rotor, and therefore a detection unit having, for example, a detection magnet and a sensor is provided. The detection unit is attached to the outside of the aperture mechanism, for example, at each part of the drive motor. The sensor detects the magnetic flux density of the detection magnet, and based on the detected magnetic flux density, the phase of the rotor angle and the phase of the excitation phase are maintained at 90 degrees to perform advance angle control, thereby driving the drive motor with high efficiency.

[0006] Publication No. 2012-2985

[0007] Incidentally, in imaging devices and interchangeable lenses that perform the above-described advance angle control, while advance angle control enables the drive motor to be driven with high efficiency, a detection unit having a detection magnet and a sensor is disposed in addition to the drive motor, which requires space for disposing the detection unit in addition to space for disposing the drive motor and aperture mechanism, which may hinder miniaturization.

[0008] Therefore, an object of the imaging device and interchangeable lens according to the present technology is to achieve miniaturization while ensuring a highly efficient driving state of the drive motor.

[0009] The imaging device and interchangeable lens according to the present technology include an aperture mechanism having a plurality of opening / closing blades, a housing that movably supports the plurality of opening / closing blades, and a driver that moves the plurality of opening / closing blades relative to the housing, a drive motor that applies a driving force to the driver is attached to the housing, and a detection unit is provided that has a detection magnet that rotates with the drive motor and a sensor that detects the rotation angle of a rotor in the drive motor, and the detection unit is positioned inside the housing.

[0010] As a result, the detector for performing advance angle control does not exist outside the diaphragm mechanism.

[0011] 2 to 7 , which show an embodiment of the present technology, and this figure is a perspective view showing an imaging device. FIG. 1 is a perspective view of an aperture mechanism etc. FIG. 2 is an exploded perspective view of an aperture mechanism etc. FIG. 3 is a cross-sectional view showing a state in which a detection unit is positioned inside a housing. FIG. 4 is a perspective view showing an example in which a detection magnet is formed integrally with a drive gear. FIG. 5 is a cross-sectional view showing an example in which a detection magnet is formed integrally with a drive gear. FIG. 6 is a block diagram of an imaging device.

[0012] Hereinafter, embodiments of the present technology will be described with reference to the accompanying drawings.

[0013] In the following embodiment, an imaging device according to the present technology is applied to a still camera. However, the scope of application of the present technology is not limited to still cameras. The present technology can be widely applied to various imaging devices incorporated in, for example, video cameras and other devices.

[0014] In the following description, the front, back, up, down, left and right directions are indicated as directions seen from the photographer when taking a picture with a still camera. Therefore, the object side is the front and the image plane side is the rear. Note that the front, back, up, down, left and right directions shown below are for convenience of explanation, and the implementation of this technology is not limited to these directions.

[0015] <General Configuration of Imaging Device, etc.> The imaging device 1 is, for example, a retractable still camera, and has a device body 2 in which an imaging element (not shown) is arranged, and a lens barrel 3 that can be extended and retracted (extended and retracted) relative to the device body 2. The imaging element may be, for example, a CCD (Charge Coupled Device) or a CMOS (Complementary Metal-Oxide Semiconductor).

[0016] The imaging device 1 may be a camera other than a retractable type in which the lens barrel 3 is fixed to the device body 2 .

[0017] Various operation units 4 are arranged on, for example, the top or rear surface of the device main body 2. The operation units 4 include, for example, a power button, a shutter button, a zoom knob, a mode switching knob, etc. A display (not shown) is arranged on the rear surface of the device main body 2.

[0018] The lens barrel 3 is provided with a photographic lens 5 located at the front end thereof. Inside the lens barrel 3, fixed lens groups and movable lens groups (not shown) are arranged behind the photographic lens 5. The movable lens groups are movable in the direction of the optical axis.

[0019] <Configuration of Aperture Mechanism, etc.> An aperture mechanism 6 is disposed inside the device body 2 (see FIG. 2). The aperture mechanism 6 functions as an iris, and is disposed, for example, inside the lens barrel 3. However, the aperture mechanism 6 may also be disposed inside the device body 2 on the front side of the image sensor.

[0020] The present technology may also be applied to an interchangeable lens that can be attached to an imaging device that does not have a lens barrel, in which case the aperture mechanism 6 is disposed inside the interchangeable lens.

[0021] The diaphragm mechanism 6 has a housing 7, a driver 8, and a plurality of opening and closing blades 9 (see FIGS. 2 and 3).

[0022] The housing 7 is configured by joining a base plate 10 and a cam plate 11 in the optical axis direction, and the base plate 10 and the cam plate 11 are formed into a thin ring shape. The housing 7 is formed into a ring shape by joining the base plate 10 and the cam plate 11, and the inner space is formed as a light transmission hole 7a (see FIG. 2).

[0023] Of the two surfaces of the base plate 10 in the thickness direction, the surface located opposite the cam plate 11 is formed as the outer surface 10a, and of the two surfaces of the cam plate 11 in the thickness direction, the surface located opposite the base plate 10 is formed as the outer surface 11a.

[0024] An insertion hole 10b is formed through the base plate 10 in the thickness direction (see FIG. 3). A placement notch 10c is formed in the outer periphery of the base plate 10 near the insertion hole 10b.

[0025] A mounting hole 11b is formed through the cam plate 11 in the thickness direction. A mounting notch 11c is formed in the outer periphery of the cam plate 11 near the mounting hole 11b. A plurality of cam holes 11d are formed in the cam plate 11 at intervals in the circumferential direction.

[0026] When the base plate 10 and the cam plate 11 are joined together, the insertion hole 10b and the positioning hole 11b are positioned side by side in the optical axis direction, and the positioning notch 10c and the positioning notch 11c are positioned side by side in the optical axis direction (see Figure 2).

[0027] When the base plate 10 and the cam plate 11 are joined to form the housing 7, an arrangement space 7b in which the driver 8 and the opening / closing blades 9 are arranged is formed inside the housing 7. Therefore, at least a part of the arrangement space 7b serves as a movement space in which the opening / closing blades 9 move.

[0028] The driver 8 functions as a driving wheel and has an annular base 12, a plurality of support projections 13 projecting radially outward from the base 12, and a driven part 14 projecting radially outward from the base 12 (see FIG. 3). At least a portion of the driver 8 is disposed in the arrangement space 7b and is supported on the base plate 10 so as to be rotatable within a certain angular range in the circumferential direction. A pin support hole 13a is formed at the tip of the support projection 13. A rack part 14a extending circumferentially is provided at the tip of the driven part 14.

[0029] The opening / closing blade 9 is composed of a sheet-like opening / closing portion 9a, a first supported pin 9b protruding from the opening / closing portion 9a in one direction in the thickness direction, and a second supported pin 9c protruding from the opening / closing portion 9a in the other direction in the thickness direction. At least a portion of the opening / closing blade 9 is arranged in the arrangement space 7b of the housing 7 with a portion of the opening / closing portion 9a overlapping a portion of the opening / closing portion 9a of another opening / closing blade 9.

[0030] The opening / closing blade 9 has a first supported pin 9b inserted into a cam hole 11d of the cam plate 11 and slidably supported therein, and a second supported pin 9c inserted into a pin support hole 13a of the driver 8 and rotatably supported therein. Therefore, when the driver 8 is rotated, the position of the first supported pin 9b in the cam hole 11d is changed, causing the opening / closing blade 9 to open or close. In the open state, the multiple opening / closing blades 9 are substantially entirely located in the arrangement space 7b, and when moved in the closing direction, they protrude inward from the arrangement space 7b (toward the light transmission hole 7a). The size of the light transmission hole 7a of the housing 7 is changed depending on the amount by which the multiple opening / closing blades 9 protrude inward from the arrangement space 7b, thereby changing (controlling) the amount of light incident on the imaging element.

[0031] A drive motor (stepping motor) 15 is attached to the base plate 10 of the housing 7 via a mounting plate 16 (see FIGS. 2 to 4). The mounting plate 16 has a shaft insertion hole 16a, and is attached to the base plate 10 from the outer surface 10a side by screws or the like. When the mounting plate 16 is attached to the base plate 10, the center of the insertion hole 10b in the base plate 10 and the center of the shaft insertion hole 16a are aligned.

[0032] The drive motor 15 has a main body 17 in which a rotor and a stator (not shown) are arranged, a rotating shaft 18 that functions as a motor shaft, and a drive gear 19 fixed to one end of the rotating shaft 18 (see Figures 3 and 4).

[0033] The drive gear 19 is formed by integrally forming a cylindrical portion 20 and gear teeth 21 provided on the outer periphery of the cylindrical portion 20, and for example, the gear teeth 21 are provided on approximately half of the axial portion of the cylindrical portion 20. However, the drive gear 19 may not be provided with the cylindrical portion 20 and may be composed only of the gear teeth 21.

[0034] The drive motor 15 has a main body 17 attached to a mounting plate 16 by screws or the like, and one end of a rotation shaft 18 is inserted through the shaft insertion hole 16a and the insertion hole 10b (see FIG. 4). Therefore, the drive gear 19 is positioned in the insertion hole 10b or the arrangement space 7b, or straddling the insertion hole 10b and the arrangement space 7b.

[0035] The gear teeth 21 of the drive gear 19 of the drive motor 15 are engaged with the rack portion 14a of the drive body 8. Therefore, the drive force of the drive motor 15 can be transmitted to the plurality of opening and closing blades 9 via the drive body 8.

[0036] A substantially cylindrical detection magnet 22 is attached to the tip end surface of the drive gear 19, i.e., the end surface 19a located on the opposite side of the drive gear 19 from the main body 17 in the axial direction. Therefore, the detection magnet 22 is positioned in the insertion hole 10b or the arrangement space 7b, or straddling the insertion hole 10b and the arrangement space 7b.

[0037] A portion of the flexible printed wiring board 23 is attached to the housing 7 (see FIGS. 3 and 4). The flexible printed wiring board 23 is connected to a control circuit (circuit board) (not shown), and one end is provided as a sensor mounting portion 23a. The flexible printed wiring board 23 has a bent portion 23b continuous with the sensor mounting portion 23a and a motor connection portion (not shown) continuous with the bent portion 23b, and the bent portion 23b is bent at a substantially right angle to the sensor mounting portion 23a.

[0038] The flexible printed wiring board 23 has its bent portion 23 b arranged in the placement notches 10 c and 11 c , and its motor connection portion connected to a power supply terminal (not shown) provided on the main body 17 of the drive motor 15 .

[0039] A sensor 24 is mounted on a sensor mounting portion 23a of the flexible printed wiring board 23. The flexible printed wiring board 23 is positioned such that the sensor mounting portion 23a is positioned on the outer surface 11a side of the cam plate 11, and the sensor 24 is inserted into the arrangement hole 11b.

[0040] When the detection magnet 22 and the sensor 24 are positioned as described above, the detection magnet 22 and the sensor 24 are positioned opposite each other in the optical axis direction, with a predetermined distance (gap) L formed between them. The detection magnet 22 and the sensor 24 form a detection unit 25. The space between the detection magnet 22 and the sensor 24 is part of the arrangement space 7b, and is the space that becomes the path of the opening and closing blade 9 when the opening and closing blade 9 is opened or closed.

[0041] <Operation of Aperture Mechanism, etc.> In the imaging device 1 configured as described above, when the drive motor 15 rotates, the drive force of the drive motor 15 is transmitted from the rack portion 14a to the drive body 8, and the drive body 8 rotates relative to the housing 7 in a direction corresponding to the rotation direction of the drive motor 15. When the drive body 8 rotates, the second supported pin 9c rotates relative to the drive body 8 in accordance with the rotation of the drive body 8, and the position of the first supported pin 9b in the cam hole 11d changes, causing the opening and closing operation of the opening / closing blade 9 to change the size of the light transmission hole 7a in the housing 7.

[0042] When the drive motor 15 rotates to open and close the opening and closing blades 9, the sensor 24 detects the magnetic flux density generated in the detection magnet 22. Specifically, the sensor 24 detects the components of the magnetic flux density in each direction.

[0043] The detection result by the sensor 24 is sent to the control circuit as a detection signal, and the rotational position (rotation angle) of the rotor is calculated based on the sent detection signal. In the imaging device 1, advance angle control is performed to maintain the phase of the rotor angle and the phase of the excitation phase at 90 degrees based on the calculated rotational position of the rotor, and the drive motor 15 is operated with high efficiency.

[0044] As described above, in the imaging device 1, the sensor 24 detects the components in each direction of the magnetic flux density generated in the detection magnet 22. Therefore, because the sensor 24 detects the balance between the components of the magnetic flux density in each direction, the rotational position of the rotor is detected without depending on the absolute value of the magnetic flux density, and it is possible to detect the rotational position of the rotor with high accuracy without depending on the size of the gap L between the detection magnet 22 and the sensor 24.

[0045] Therefore, high positional accuracy of the detection magnet 22 and the sensor 24 relative to the housing 7 is not required, and high-precision positioning of the drive motor 15 and the flexible printed wiring board 23 relative to the housing 7 is not required, which allows for reduced manufacturing costs of the imaging device 1.

[0046] Furthermore, since the detection magnet 22 is attached to the end surface 19a of the drive gear 19, it is possible to position the detection magnet 22 and the sensor 24 close to each other, thereby ensuring a high signal-to-noise ratio and improving the detection accuracy of the detection unit 25.

[0047] <Other arrangements of the detection magnet> The above shows an example in which the detection magnet 22 is attached to the end face 19a of the drive gear 19, but the detection magnet 22 may also be formed integrally with the drive gear 19 and attached to the drive gear 19 (see Figures 5 and 6).

[0048] The detection magnet 22 is formed integrally with the drive gear 19 by, for example, insert molding, and is located, for example, inside the portion of the cylindrical portion 20 where the gear teeth 21 are formed. Note that a portion of the detection magnet 22 may be in a state where it protrudes from the end face 19 a in the axial direction.

[0049] In this way, the detection magnet 22 is attached to the drive gear 19 by being molded integrally with the drive gear 19, and the attachment of the detection magnet 22 is carried out in the process of being molded integrally with the drive gear 19. This enables the manufacturing time of the imaging device 1 to be shortened, thereby reducing manufacturing costs and improving mass productivity.

[0050] Furthermore, since the detection magnet 22 is positioned inside the drive gear 19, no space is required for arranging the detection magnet 22 outside the drive motor 15, which simplifies the structure and makes it possible to further reduce the size of the imaging device 1.

[0051] Furthermore, in the imaging device 1, one end of the rotating shaft 18 may be configured to protrude from the drive gear 19, and the protruding portion may be positioned inside the housing 7 with a detection magnet 22 attached to it.

[0052] <Summary> As described above, the imaging device 1 is provided with a detection unit 25 having a detection magnet 22 that rotates along with the drive motor 15 and a sensor 24 that detects the rotation angle of the rotor in the drive motor 15, and the detection unit 25 is located inside the housing 7.

[0053] Therefore, since the detection unit 25 for performing advance angle control is not located outside the aperture mechanism 6, the imaging device 1 can be made smaller while ensuring that the drive motor 15 is driven in a highly efficient manner.

[0054] In addition, an arrangement space 7b is formed inside the housing 7, at least a portion of which is used as a movement space for the opening and closing blade 9, and the detection magnet 22 and the sensor 24 are positioned on opposite sides of the opening and closing blade 9 that moves in the movement space.

[0055] Therefore, the opening / closing blade 9, which is moved relative to the housing 7, does not interfere with the detection magnet 22 and the sensor 24, and the imaging device 1 can be made smaller while ensuring the proper operating state of the opening / closing blade 9.

[0056] Furthermore, even when the aperture mechanism 6 is placed inside the interchangeable lens, the detection unit 25 will not be located outside the aperture mechanism 6, so the interchangeable lens can be made smaller while still ensuring that the drive motor 15 is driven at a high efficiency.

[0057] Furthermore, in the interchangeable lens, the detection magnet 22 and the sensor 24 are positioned on opposite sides of the opening / closing blade 9 that moves in the movement space, so the opening / closing blade 9 that moves relative to the housing 7 does not interfere with the detection magnet 22 and the sensor 24, and the interchangeable lens can be made smaller while ensuring the proper operating state of the opening / closing blade 9.

[0058] <One Embodiment of Imaging Apparatus> An example of the configuration of one embodiment of an imaging apparatus according to the present technology will be described below (see FIG. 7 ).

[0059] The imaging device 1 has a camera block 90 (lens barrel 3) that performs imaging functions, a camera signal processing unit 91 that performs signal processing such as analog-to-digital conversion of captured image signals, and an image processing unit 92 that performs recording and playback processing of image signals. The imaging device 1 also has a display unit (display) 93 that displays captured images, etc., an R / W (reader / writer) 94 that writes and reads image signals to a memory 99, a CPU (Central Processing Unit) 95 that controls the entire imaging device 1, a lens drive control unit 96 that controls the drive of a lens arranged in the camera block 90, and an operation unit 97 (operation unit 4) such as various switches that are used by the user to perform required operations.

[0060] The imaging device 1 is provided with an imaging element 98 such as a CCD or CMOS that converts an optical image captured by the camera block 90 into an electrical signal.

[0061] The camera signal processing unit 91 performs various signal processing such as converting the output signal from the image sensor 98 into a digital signal, removing noise, correcting image quality, and converting into a luminance and color difference signal.

[0062] The image processing unit 92 performs processes such as compression encoding and decompression decoding of image signals based on a predetermined image data format, and conversion of data specifications such as resolution.

[0063] The display unit 93 has a function of displaying various data such as the operation status of the user on the operation unit 97 and the captured image, etc. The imaging device 1 does not necessarily have to be provided with the display unit 93, and may be configured so that the captured image data is sent to another display device and the image is displayed thereon.

[0064] The R / W 94 writes image data coded by the image processing unit 92 into the memory 99 and reads image data recorded in the memory 99 .

[0065] The CPU 95 functions as a control processing unit that controls each circuit block provided in the imaging device 1, and controls each circuit block based on instruction input signals from the operation unit 97, etc.

[0066] The lens drive control unit 96 controls a drive source that moves the lens based on a control signal from the CPU 95 .

[0067] The operation unit 97 outputs to the CPU 95 an instruction input signal in response to an operation by the user.

[0068] The memory 99 is, for example, a semiconductor memory that is detachable from a slot connected to the R / W 94 or a semiconductor memory that is pre-installed inside the imaging device 1 .

[0069] The operation of the imaging device 1 will be described below.

[0070] In a standby state for photographing, a photographed image signal is output to the display unit 93 via the camera signal processing unit 91 and displayed as a camera-through image under the control of the CPU 95. When an instruction input signal is input from the operation unit 97, the CPU 95 outputs a control signal to the lens drive control unit 96, and the lens is moved under the control of the lens drive control unit 96.

[0071] When a photographing operation is performed in response to an instruction input signal from the operation unit 97, the photographed image signal is output from the camera signal processing unit 91 to the image processing unit 92, where it is compressed and encoded and converted into digital data in a predetermined data format. The converted data is output to the R / W 94 and written to the memory 99.

[0072] When image data recorded in memory 99 is to be reproduced, the R / W 94 reads out the specified image data from memory 99 in response to an operation on the operation unit 97, and after the image processing unit 92 performs an expansion and decoding process, the reproduced image signal is output to the display unit 93 and the reproduced image is displayed.

[0073] In this technology, "imaging" refers to processing that includes only some or all of a series of processing, from photoelectric conversion processing that converts light captured by the imaging element 98 into an electrical signal, to processing by the camera signal processing unit 91 that converts the output signal from the imaging element 98 into a digital signal, noise removal, image quality correction, conversion into luminance and color difference signals, etc., to compression encoding / decompression decoding processing of the image signal based on a predetermined image data format and conversion processing of data specifications such as resolution, etc., by the image processing unit 92, and writing processing of the image signal to the memory 99 by the R / W 94.

[0074] That is, "imaging" may refer only to the photoelectric conversion process of converting the light taken in by the imaging element 98 into an electrical signal, or may refer to the process from the photoelectric conversion process of converting the light taken in by the imaging element 98 into an electrical signal to the process of converting the output signal from the imaging element 98 into a digital signal by the camera signal processing unit 91, noise removal, image quality correction, conversion into luminance and color difference signals, etc. ... to the process of converting the output signal from the imaging element 98 into an electrical signal by the image processing unit 91, noise removal, image quality correction, conversion into luminance and color difference signals, etc. It may also refer to processes such as the photoelectric conversion process by the image sensor 98 to convert the light captured by the image sensor 98 into an electrical signal, the conversion of the output signal from the image sensor 98 into a digital signal, noise removal, image quality correction, conversion into luminance and color difference signals, etc. by the camera signal processing unit 91, and the compression coding / decompression decoding process by the image processing unit 92 to convert the image signal into a predetermined image data format and conversion of data specifications such as resolution, etc., by the image processing unit 92, or the writing process of the image signal into the memory 99 by the R / W 94.

[0075] In the above processes, the order of the processes may be changed as appropriate.

[0076] In addition, in the present technology, the camera block 90 and the imaging device 1 may be configured to include only some or all of the imaging element 98, camera signal processing unit 91, image processing unit 92, and R / W 94 that perform the above processing.

[0077] Furthermore, the camera block 90 may be configured to include some of the image pickup element 98 , the camera signal processing unit 91 , the image processing unit 92 , and the R / W 94 .

[0078] <Present Technology> The present technology can also be configured as follows.

[0079] (1) An imaging device comprising an aperture mechanism having a plurality of opening / closing blades, a housing that movably supports the plurality of opening / closing blades, and a drive body that moves the plurality of opening / closing blades relative to the housing, wherein a drive motor that applies a drive force to the drive body is attached to the housing, and a detection unit is provided that has a detection magnet that rotates with the drive motor and a sensor that detects the rotation angle of a rotor in the drive motor, and the detection unit is located inside the housing.

[0080] (2) The imaging device according to (1), wherein an arrangement space is formed inside the housing, at least a part of which is a movement space for the opening / closing blade, and the detection magnet and the sensor are positioned on opposite sides of the opening / closing blade that moves in the movement space.

[0081] (3) The imaging device according to (2), wherein the drive motor is provided with a rotating shaft that functions as a motor shaft and a drive gear fixed to the rotating shaft, and the detection magnet is attached to an end face of the drive gear in the axial direction.

[0082] (4) The imaging device according to (2), wherein the drive motor is provided with a rotating shaft that functions as a motor shaft and a drive gear fixed to the rotating shaft, and the detection magnet is attached to the drive gear by being integrally molded with the drive gear.

[0083] (5) The imaging device according to (4), wherein the detection magnet is positioned inside the drive gear.

[0084] (6) An interchangeable lens comprising an aperture mechanism having a plurality of opening / closing blades, a housing that movably supports the plurality of opening / closing blades, and a drive body that moves the plurality of opening / closing blades relative to the housing, wherein a drive motor that applies a drive force to the drive body is attached to the housing, and a detection unit is provided that has a detection magnet that rotates with the drive motor and a sensor that detects the rotation angle of a rotor in the drive motor, and the detection unit is located inside the housing.

[0085] REFERENCE SIGNS LIST 1 imaging device 6 aperture mechanism 7 housing 7b arrangement space 8 driver 9 opening / closing blade 15 drive motor 18 rotating shaft 19 drive gear 19a end surface 22 detection magnet 24 sensor 25 detection unit

Claims

1. An imaging device comprising an aperture mechanism having a plurality of opening / closing blades, a housing that movably supports the plurality of opening / closing blades, and a driver that moves the plurality of opening / closing blades relative to the housing, wherein a drive motor is attached to the housing to apply a driving force to the driver, and wherein a detection unit is provided that has a detection magnet that rotates with the drive motor and a sensor that detects the rotation angle of a rotor in the drive motor, and the detection unit is located inside the housing.

2. The imaging device according to claim 1, wherein an arrangement space is formed inside the housing, at least a part of which is a movement space for the opening / closing blade, and the detection magnet and the sensor are positioned on opposite sides of the opening / closing blade that moves in the movement space.

3. The imaging device according to claim 2, wherein the drive motor is provided with a rotating shaft that functions as a motor shaft and a drive gear fixed to the rotating shaft, and the detection magnet is attached to the end face of the drive gear in the axial direction.

4. The imaging device according to claim 2, wherein the drive motor is provided with a rotating shaft that functions as a motor shaft and a drive gear fixed to the rotating shaft, and the detection magnet is attached to the drive gear by being molded integrally with the drive gear.

5. The imaging device according to claim 4, wherein the detection magnet is positioned inside the drive gear.

6. An interchangeable lens comprising an aperture mechanism having a plurality of opening / closing blades, a housing that movably supports the plurality of opening / closing blades, and a drive body that moves the plurality of opening / closing blades relative to the housing, wherein a drive motor is attached to the housing to apply a drive force to the drive body, and a detection unit is provided that has a detection magnet that rotates with the drive motor and a sensor that detects the rotation angle of a rotor in the drive motor, and the detection unit is located inside the housing.

Images