JP2013178340A - Lens barrel and imaging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lens barrel capable of easily detecting the applied state of electrically conductive coating after assembly and to provide an imaging apparatus.SOLUTION: A lens barrel 100 which is supported by a camera body 200 and at least incorporates an electrical part in a lens housing formed in a cylindrical shape includes a conductive electrically conductive coating 30 which is applied to the inner circumferential surface of the lens housing and an inspection electrode 32a and an inspection electrode 32b which are connected to positions electrically separated from each other in the continuous electrically conductive coating 30. The inspection electrode 32a and the inspection electrode 32b are exposed to the outside of the lens housing.

Description

  The present invention relates to a lens barrel such as an interchangeable lens and an image pickup apparatus including the lens barrel.

Conventionally, as an interchangeable lens that can be attached to a camera body via a mount, a lens having functions such as autofocus and camera shake correction is known (for example, see Patent Document 1).
Moreover, in order to suppress the influence of noise on the signal wiring, an interchangeable lens is proposed in which a wiring having a shield pattern by an electrical contact is disposed between the lens housing and the signal line ( For example, see Patent Document 2).

The interchangeable lens of the imaging device described above includes a motor for autofocus and camera shake correction inside the lens housing, and the lens housing may be formed of resin for weight reduction and the like. In this case, electromagnetic noise radiated inside the lens housing may pass through the resin lens housing and adversely affect the camera body.
In order to prevent the adverse effect of the electromagnetic noise on the camera body side, for example, a coating film is formed by conductive coating on the inside of the resin lens housing to shield the electromagnetic noise emitted from the lens housing to the outside. It is conceivable.

Japanese Patent No. 4400100 Japanese Patent No. 4434233

  By the way, when applying the conductive coating described above to the inside of the lens housing, the only way to inspect the coating state of the conductive coating is to measure the resistance value at the part level before assembly, and the lens barrel once assembled With respect to the above, it becomes necessary to disassemble the lens barrel one by one when confirming the application state of the conductive coating. Therefore, there is a problem that the inspection work becomes troublesome and the burden on the worker increases.

  The present invention has been made in view of the above circumstances, and provides a lens barrel and an imaging apparatus capable of easily detecting the application state of the conductive coating after assembly.

  In order to solve the above-described problems, the present invention provides a lens barrel that is supported by a camera body and includes at least an electrical component inside a cylindrical lens housing, and is applied to the inner peripheral surface of the lens housing. A conductive conductive coating that is electrically connected, and a first electrode and a second electrode that are electrically connected to each other in the continuous conductive coating, wherein the first electrode and the second electrode are, It is exposed outside the lens housing.

  According to the present invention, by applying a probe or the like to each of the first electrode and the second electrode and measuring the resistance value, it is possible to inspect the application state of the conductive coating corresponding to the resistance value. Therefore, since the application state of the conductive coating inside the lens barrel can be easily inspected with the lens barrel assembled, the burden on the operator can be reduced.

1 is a block diagram illustrating an electrical configuration of a main part of an imaging device including an interchangeable lens and a camera body in an embodiment of the present invention. It is a perspective view of the said interchangeable lens. It is the perspective view seen from the inner side of the lens-barrel cover member of the said interchangeable lens. It is a longitudinal cross-sectional view of the test | inspection electrode attached to the said lens-barrel cover member. It is an inner side view of the said lens-barrel cover member. FIG. 6 is an inner side view corresponding to FIG. 4 in a modified example of the present invention.

  Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an electrical configuration of main parts of an imaging apparatus 1 including a lens barrel 100 and a camera body 200 according to this embodiment.
As shown in FIG. 1, the imaging apparatus 1 includes a lens barrel 100 and a camera body 200, and electrical connection between the lens barrel 100 and the camera body 200 is mainly performed by electrical contacts 6-1. 6-2, 6-3, 6-4, 6-5, 6-6.
A battery B as a power source is loaded in the camera body 200, and power is supplied from the battery B to the camera body 200 and the lens barrel 100. The negative terminal of the battery B is grounded to the housing 7 of the camera body 200 and is connected to the circuit ground (GGND) of the lens barrel 100 via the electrical contact 6-6. Further, the housing 7 (MGND) of the camera body 200 is connected to the lens mount portion 20 of the lens barrel 100.

The positive terminal of the battery B is connected to the power supply switch 11 controlled by the body CPU 3 and the power supply circuit 11 of the lens barrel 100, the autofocus motor (AFM) 14, and the camera shake correction motor (VRM) via the electrical contact 6-1. ) 15.
Further, the positive terminal of the battery B is connected to the power supply circuit 2 controlled by the body CPU 3 provided in the camera body 200, and is connected to the lens CPU 9 of the lens barrel 100 through the electrical contact 6-2.

  The power supply circuit 2 of the camera body 200 is turned on / off in accordance with a control signal (CTL) from the body CPU 3, and outputs the voltage of the battery B input from the input terminal (IN) to the output terminal (OUT) when turned on. . Thus, when the power supply circuit 2 is turned on, the voltage from the battery B is applied to the body CPU3 via the diode D2, and also applied to the lens CPU9 via the electrical contact 6-2 as a circuit power supply on the lens barrel 100 side. Is done. Since the positive terminal of the battery B is also connected to the body CPU 3 through the path via the diode D1, the voltage from the battery B is applied to the body CPU 3 when the battery B is loaded in the camera body 200, and the body CPU 3 to start.

  The power supply switch 5 is turned on / off according to a control signal transmitted from the body CPU 3. When the power supply switch 5 is turned on, the voltage from the battery B is applied to the power supply circuit 11 on the lens barrel 100 side, the AF motor 14 and the VR motor 15 via the electrical contact 6-1.

  An external switch group 4 provided in the camera body 200 is connected to the body CPU 3. The external switch group 4 includes a half-push switch, a full-push switch, and the like, and outputs an operation signal corresponding to each switch operation to the body CPU 3. The half-press switch is turned on / off in conjunction with a pressing amount of a shutter button (not shown), is turned on when the pressing amount reaches the half-pressing operation amount, and is turned off when the half-pressing operation amount is not reached. The full push switch is turned on when the amount of pressing the shutter button reaches a full push operation amount larger than the half push operation amount, and is turned off when the full push operation amount is not reached.

  The body CPU 3 performs a well-known exposure calculation and a well-known autofocus (AF) calculation when the half-press switch is turned on, and starts photographing control when the full-press switch is turned on. The body CPU 3 further communicates with the lens CPU 9 after the AF calculation. A communication line with the lens CPU 9 includes a DATA line L1, a handshake (H / S) line L2, and a clock (CLK) line L3. Information such as the movement amount, movement direction, and movement start instruction of the focus optical system calculated by the AF calculation is transmitted from the body CPU 3 to the lens CPU 9.

  The DATA line L1 is a transmission line that is connected by the electrical contact 6-3 and transmits / receives various information held by the camera body 200 and various information held by the lens barrel 100 to / from each other. In the lens barrel 100, a pull-up resistor 17 is interposed between the DATA line L1 and the circuit power supply (electrical contact 6-2).

The handshake line L2 is connected by an electrical contact 6-4 to transmit / receive information for determining whether or not the lens barrel 100 is mounted on the camera body 200 side, or to a signal from the camera body 200. On the other hand, it is a transmission line that outputs a standby signal from the lens barrel 100.
The clock line L3 is a transmission line that is connected by the electrical contact 6-5 and transmits a clock signal for clock synchronization from the body CPU3 to the lens CPU9.

  On the other hand, the power supply circuit 11 of the lens barrel 100 is turned on / off according to the control signal (CTL) of the lens CPU 9, and when turned on, the voltage of the battery B input from the input terminal (IN) is output to the output terminal (OUT). Output to. Thereby, the voltage from the battery B is applied to the AF motor control circuit 12 and the shake correction circuit 13 when the power supply circuit 11 is turned on.

  The lens CPU 9 is activated when the voltage of the battery B is applied from the camera body 200 via the electrical contact 6-2, and communicates with the body CPU 3 and transmits a control command to the AF motor control circuit 12. Then, the rotation of the AF motor 14 is controlled. In addition, the lens CPU 9 transmits a control command to the blur correction circuit 13 to control the driving of the VR motor 15.

  The AF motor 14 is a drive source that moves the focus optical system back and forth in the optical axis direction. The AF motor control circuit 12 starts driving the AF motor 14 in accordance with a control signal transmitted from the lens CPU 9 and detects it. The amount of movement of a focus optical system (not shown) for focus adjustment is detected using a detection signal from an apparatus (not shown). Then, the AF motor control circuit 12 generates a drive voltage so that the amount of movement of the focus optical system matches the amount of movement according to the control command of the body CPU 3, and applies this drive voltage to the AF motor 14. By applying this drive voltage, the AF motor 14 rotates, the focus optical system is moved to the in-focus position, and a sharp image of the main subject is formed on the photosensitive member (not shown).

  The VR motor 15 is a drive source for moving a camera shake correction optical system (not shown) forward and backward in a direction orthogonal to the optical axis direction. The camera shake correction circuit 13 is a photosensitive member according to a control signal transmitted from the lens CPU 9. The amount of shaking of the subject image formed on the top is calculated, and the VR motor 15 is driven according to the amount of shaking.

  Then, the shake correction circuit 13 generates a drive voltage so as to cancel the calculated amount of shaking, and applies this drive voltage to the VR motor 15. The VR motor 15 is driven by the application of the driving voltage, the camera shake correction optical system is moved, and the subject image on the photosensitive member is relatively shaken due to the shaking of the lens barrel 100 (that is, the camera system). It can be suppressed.

  Connected to the lens CPU 9 is an external operation switch group 10 provided on the housing of the lens barrel 100 (configured by the housing body 21 and the lens barrel cover member 22). The external operation switch group 10 includes a manual focus switch, a focus limit switch, an image stabilization mode switch, and the like, and outputs an operation signal corresponding to each switch operation to the lens CPU 9. The manual focus switch is a switch that is operated when the photographer manually adjusts the focus, and the focus limit switch is a switch that is operated in accordance with the subject distance that is the target of the AF operation. The anti-vibration mode switch is a switch that is operated in accordance with an assumed camera shake situation.

FIG. 2 is a perspective view of a lens barrel 100 according to an example of this embodiment. The lens barrel 100 according to an example of this embodiment is a so-called zoom lens, but is not limited thereto, and may be a single focus type lens.
The lens barrel 100 includes a lens mount portion 20 that is supported by being engaged with the camera body 200, a substantially cylindrical barrel main body portion 21 that is a housing that houses an optical lens group (not shown), and the like. A lens barrel cover member 22 that is a casing provided between the lens barrel main body portion 21 and the lens mount portion 20 is provided.

  The lens mount unit 20 is provided with a plurality of lens side contacts 6 which are contacts on the lens barrel 100 side in the electrical contacts 6-1 to 6-6 described above. These lens side contacts 6 are formed so as to be able to appear and retract elastically, and are electrically insulated from the metal lens mount portion 20. Here, in a state where the lens barrel 100 is mounted on the camera body 200, the lens side contacts 6 are elastically brought into contact with the corresponding contacts (not shown) on the camera body 200 side. The lens mount unit 20 is electrically connected to the housing 7 on the camera body side.

  The lens barrel main body 21 has a zoom ring 23 that changes the distance between the optical lenses and changes the focal length (view angle) along the circumferential direction on the outer peripheral surface thereof, and the optical lens is moved forward and backward in the optical axis direction. A focus ring 24 that changes the focal position is rotatably provided.

  The lens barrel cover member 22 is resin-molded separately from the lens barrel main body portion 21 and is compressed toward the lens mount portion 20 side from the cylindrical portion 22a connected to the outer peripheral surface of the lens barrel main body portion 21. And an inclined portion 22b formed to have a diameter. An opening 22c is formed at the edge of the inclined portion 22b, and the lens mount portion 20 is exposed to the outside through the opening 22c.

  Referring to FIGS. 3 to 5 together, the lens barrel cover member 22 is provided with a conductive coating 30 on the entire inner surface thereof to prevent electromagnetic noise from passing in and out of the lens barrel cover member 22. . The conductive coating 30 is electrically connected to the lens mount unit 20 and forms a coating film having a substantially uniform thickness containing, for example, metal powder or carbon powder.

The inclined portion 22b of the lens barrel cover member 22 is provided with a hole 31 that penetrates in the thickness direction of the inclined portion 22b, and inside the hole 31 from the inner side to the outer side in the thickness direction of the inclined portion 22b. Two inspection electrodes 32a and 32b extending in the direction are inserted. The inspection electrodes 32 a and 32 b are for enabling an electrical connection from the outside of the lens barrel cover member 22 to the conductive coating 30, and a substantially cylindrical penetrating portion 33 located inside the hole 31; A substantially plate-like contact portion 34 that contacts the inner peripheral surface of the lens barrel cover member 22 to which the conductive coating 30 is applied is provided.
The contact portion 34 is connected to the base side of the penetrating portion 33 and extends in the circumferential direction of the lens barrel cover member 22.

The end surface 35 on the end side of the penetrating portion 33 is exposed to the outside of the lens barrel 100 so as to be touched by a probe or the like from the outside of the barrel cover member 22, for example. More specifically, an end surface 35 is disposed in the vicinity of the outer peripheral surface of the lens barrel cover member 22 inside the hole 31. The end surface 35 of the penetrating portion 33 may be touched by a probe or the like. For example, the end surface 35 may be disposed flush with the outer peripheral surface of the lens barrel cover member 22 or slightly protruded from the outer peripheral surface. Anyway.
The outer surface of the contact portion 34 on the penetrating portion 33 side is attached so that the entire surface is in contact with the coating film of the conductive coating 30.

  The two holes 31 and the inspection electrodes 32a and 32b described above are disposed at positions facing each other across the axis center (axis) C of the lens barrel cover member 22, that is, at a position that is line symmetric with respect to the axis center C as the symmetry axis. . Thereby, it becomes possible to arrange | position the test | inspection electrodes 32a and 32b as spaced apart as possible.

  Therefore, according to the lens barrel 100 in the above-described embodiment, in a state where the lens barrel 100 is assembled, the probe is pressed against the two inspection electrodes 32a and 32b, and the resistance value is measured. Since the application state of the conductive coating 30 corresponding to the value can be inspected, the application state of the conductive coating 30 can be easily inspected, and as a result, the burden on the operator can be reduced. In addition, since the resistance value tends to increase when the state of the conductive coating 30 is not normal, the application state of the conductive coating 30 is inspected by measuring the resistance value of the normal conductive coating 30 in advance. Can do.

  Further, since the conductive coating 30 is applied to the inner surface of the lens barrel cover member 22 arranged on the side adjacent to the lens mount portion 20 supported by the camera body 200, AF which is an electrical component on the lens barrel 100 side. Since electromagnetic noise radiated from the motor 14 or the VR motor 15 can be prevented from passing through the resin lens barrel cover member 22 to the camera body 200 side, the influence of electromagnetic noise on the camera body 200 side is reduced. Can be suppressed.

  Further, by disposing the two inspection electrodes 32 a and 32 b on the inclined portion 22 b of the lens barrel cover member 22, the inspection electrodes 32 a and 32 b exposed to the outside in a state where the lens barrel 100 is attached to the camera body 200. Since the end surface 35 faces the camera body 200 side and is arranged on the axial center C side in the radial direction with respect to the outer peripheral surface of the barrel main body 21, the user's hand is prevented from touching the end surface 35 during shooting or the like. can do. Furthermore, in a state where the lens barrel 100 is not attached to the camera body 200, the probe or the like can be easily brought into contact with the end surfaces 35 of the inspection electrodes 32a and 32b. The application status can be easily inspected.

  Furthermore, the two inspection electrodes 32a and 32b are arranged at positions facing each other across the axis center C of the lens barrel cover member 22, thereby lengthening the electric circuit by the conductive coating 30 between the two inspection electrodes 32a and 32b. Since it can be set, it is possible to detect a wider range of application state of the conductive coating 30 by resistance measurement.

Note that the present invention is not limited to the configuration of the imaging device 1 of the above-described embodiment, and the design can be changed without departing from the gist thereof.
For example, in the lens barrel 100 of the above-described embodiment, an example in which the inspection electrodes 32a and 32b are symmetrically arranged at positions facing each other across the axis center C has been described. However, the inspection electrodes 32a and 32b are arranged symmetrically. It is not limited to this, and it is only necessary that the lens barrel cover member 22 be spaced apart as far as possible according to the shape of the lens barrel cover member 22.

  Further, either of the two inspection electrodes 32a and 32b is attached to the metallic lens mount portion 20 exposed to the outside of the lens barrel 100 and connected to the conductive coating 30, or the lens side contact 6 of the electrical contact 6-6. One can be replaced. By comprising in this way, since the number of inspection electrodes can be reduced and a number of parts can be reduced, it can prevent that an assembly man-hour and cost increase.

  Furthermore, although the lens barrel 100 described above has been described with respect to the case where the AF lens 14 or the VR motor 15 is provided in the lens barrel 100 as an electrical component, only one of the AF motor 14 and the VR motor 15 is provided. In addition, an aperture motor that adjusts the amount of light passing through the lens barrel 100 and an aperture drive circuit that drives and controls the aperture motor may be provided.

  In the above-described embodiment, an example in which the above-described conductive coating 30 is applied to the entire inner peripheral surface of the lens barrel cover member 22 has been described. However, the application range of the conductive coating 30 is continuously formed. For example, as shown in FIG. 6, a substantially C-shaped range in which only one portion is interrupted in the circumferential direction of the lens barrel cover member 22 may be used. In this case, it is preferable to arrange the inspection electrodes 32a and 32b across a portion where the conductive coating 30 is interrupted. With such an arrangement, the electric path of the conductive coating 30 between the two inspection electrodes 32a and 32b becomes longer, and a wider range of application states of the conductive coating 30 can be detected by resistance measurement.

  And although the case where the application area | region of the electrically conductive coating 30 is one continuous area | region was demonstrated, you may make it divide | segment an application area | region into two and provide two test | inspection electrodes for every application | coating area | region.

  Further, the case where the conductive coating 30 is applied only to the lens barrel cover member 22 has been described, but when the resin-made lens barrel main body 21 is used, the conductive coating 30 is applied to the inner peripheral surface of the lens barrel main body 21. May be. A plurality of inspection electrodes may be provided on the lens barrel main body 21 to which the conductive coating 30 is applied. By doing in this way, while being able to further reduce the influence of the electromagnetic noise radiated | emitted from the electrical component in the lens-barrel 100, the application | coating condition of the conductive coating 30 of the internal peripheral surface of the lens-barrel main-body part 21 is easy. Can be detected.

Moreover, although the case where the two inspection electrodes 32a and 32b are provided has been described, three or more inspection electrodes are provided, the resistance value of the conductive coating 30 between the respective inspection electrodes is measured, and the application state of the conductive coating 30 is determined. You may make it detect.
Further, although the interchangeable lens type imaging apparatus has been described as an example, it may be applied to a lens barrel of a fixed lens type imaging apparatus.
Furthermore, the shape of the inspection electrodes 32 a and 32 b is not limited to the above-described shape as long as the base side is electrically connected to the conductive coating 30 and the end surface 35 is exposed to the outside of the lens barrel 100. Absent.

1 Imaging device 12 AF motor control circuit (electrical parts)
13 Shake correction circuit (electrical parts)
14 AF motor (electrical parts)
15 VR motor (electrical parts)
20 Lens mount 22 Lens barrel cover member (frame)
22b Inclined portion 30 Conductive coating 32a Inspection electrode (first electrode)
32b Inspection electrode (second electrode)
100 Lens barrel 200 Camera body C axis center

Claims (6)

In a lens barrel that is supported by a camera body and has at least an electrical component inside a cylindrical lens housing,
Conductive conductive coating applied to the inner peripheral surface of the lens housing;
A first electrode and a second electrode connected to positions electrically separated from each other in the continuous conductive coating;
The lens barrel, wherein the first electrode and the second electrode are exposed to the outside of the lens housing. The conductive coating is
The lens barrel according to claim 1, wherein the lens barrel is applied to a region of the lens housing that is supported by the camera body. The lens housing is
It has an inclined portion that decreases in diameter toward the side supported by the camera body,
The lens barrel according to claim 1 or 2, wherein the first electrode and the second electrode are disposed on the inclined portion. The first electrode and the second electrode are:
The lens barrel according to any one of claims 1 to 3, wherein the lens barrel is disposed at a position facing each other across an axis center of the lens housing.   5. The lens barrel according to claim 1, wherein one of the first electrode and the second electrode is disposed in a lens mount portion connected to the camera body.   An imaging device comprising the lens barrel according to any one of claims 1 to 5.

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