TWI653499B - Filter switching device, aperture device and camera - Google Patents

Abstract

Provided is a technology capable of achieving miniaturization of a filter switching device.

The filter switching device 6 of the present invention includes: a first filter unit 51 and a second filter unit 52, each of which has an optical filter (54, 61) that can be arranged in an incident light path; and a filter switching mechanism 53. In a manner of exchanging positions of the first filter unit 51 and the second filter unit 52, the first filter unit 51 and the second filter unit 52 are rotated and moved in opposite directions. The filter switching mechanism 53 is provided with a gear transmission mechanism 68 that transmits the driving force of the filter driving section to the first filter unit 51 and the second filter unit 52. The gear transmission mechanism 68 is composed of four gears (59, 65, 78, 86).

Description

Filter switching device, aperture device and camera

The present invention relates to a filter switching device for switching an optical filter, and an aperture device and a camera provided with the filter switching device.

An aperture device that adjusts the amount of light incident from the outside (hereinafter, also referred to as the "incident light amount") is incorporated in various cameras including a surveillance camera. The aperture device adjusts (corrects) the amount of incident light by changing the size of the aperture opening existing on the light path of the incident light. As the structure of the aperture device, there is a person who adjusts the amount of light by moving the aperture member. Specifically, a person using a pair of aperture blades as an aperture member is known (for example, refer to Patent Document 1).

In addition, a day and night surveillance camera is incorporated with a photographic element capable of color photography. In this type of surveillance camera, the shooting mode is switched when the subject is bright and when the subject is dim. Specifically, the photography mode is switched by using a color photography mode when photographing a bright subject during the day and the like, and using a monochrome photography mode when photographing a dark subject at night and the like.

Among the above-mentioned surveillance cameras, there is a function of switching an optical filter in accordance with a switching function of a shooting mode (for example, refer to Patent Documents 1 and 2). Specifically, in the color photography mode, an infrared blocking filter (ICF filter) is used for shooting. In the monochrome photography mode, no infrared blocking filter is used, or other optical filters are penetrated. Mirror for shooting. Therefore, in the case of shooting in the color photography mode, light incident from the outside reaches the imaging element through an infrared blocking filter. In the case of shooting in the monochrome photography mode, the light incident from the outside does not pass through the infrared blocking filter or penetrate the other optical filters to reach the imaging element.

In a filter switching device used in a surveillance camera or the like, the optical filter is switched by changing the configuration of the optical filter. For example, the aforementioned Patent Document 1 discloses a configuration in which two optical filters are mounted adjacent to each other on a common filter support member, and the filter support member is arranged in the direction in which the optical filters are arranged Move to switch the optical filter. In addition, the aforementioned Patent Document 2 discloses a configuration in which an optical filter is supported by a filter supporting member, and the optical filter is switched by moving the filter supporting member.

[Prior technical literature] [Patent Literature]

Patent Document 1: Japanese Patent Laid-Open No. 2003-348398

Patent Document 2: Japanese Patent Laid-Open No. 2007-17594

In recent years, with the popularization of surveillance cameras, the requirements for high resolution have become higher and higher. In order to realize the high resolution of the surveillance camera, it is necessary to increase the number of pixels of the photographic element used in the surveillance camera. However, if the number of pixels of a photographic element is simply increased, the size of the photographic element will increase. In addition, if the pixel size of each pixel is reduced, the size of the pixel element will not be increased, but in this case, it is easily affected by noise. Therefore, in order to suppress the influence of noise and realize the effect of surveillance cameras High resolution requires the use of larger-sized photographic elements than those used so far. In this case, it is necessary to ensure the maximum diameter of the aperture opening in the aperture device installed in the surveillance camera in accordance with the size of the imaging element.

However, as a filter switching device having two optical filters, if the configuration described in the aforementioned Patent Document 1 is used, for example, the following disadvantages occur in the pursuit of high resolution of a surveillance camera.

That is, in the filter switching device described in Patent Document 1, two optical filters are mounted adjacent to each other on a common filter supporting member, and the filter supporting member is arranged on the optical filters. A mechanism that moves in the direction. Therefore, when the first optical filter is arranged in the aperture opening of the diaphragm device, it is necessary to arrange (retreat) the second optical filter in advance at a position deviated to one side from the aperture opening in advance. In addition, when the second optical filter is arranged in the aperture opening, it is necessary to arrange (retract) the first optical filter in advance at a position deviating from the aperture opening to the other side. Therefore, the space for movement necessary for switching the optical filters (hereinafter referred to as the "space for filter switching") needs to substantially secure a space for only three optical filters arranged and arranged. Thereby, the diaphragm device becomes larger. In particular, in order to realize the high resolution of the surveillance camera while suppressing the influence of the above noise, if the maximum diameter of the aperture opening is greatly ensured, the size of the optical filter will also increase, so the space for filter switching will gradually The enlargement makes the size of the aperture device significantly larger.

Therefore, the present inventor has proposed a new filter switching device that can reduce the space for filter switching (Japanese Patent Application No. 2012-220064). In this filter switching device, a mechanism is used to switch the positions of the two filter units, and the two filter units are moved to switch the optical filters arranged in the incident light path. In addition, a configuration is adopted in this filter switching device, which uses a gear transmission mechanism including three intermediate gears to move the two filter units in opposite directions to each other.

However, recently, it has been required to make the filter switching device smaller. The present invention has been made to meet such a demand.

A first aspect of the present invention is a filter switching device, comprising: a first filter unit and a second filter unit, each of which has an optical filter, and these optical filters can be arranged on incident light An incident light path passed therethrough; and a filter switching mechanism that supports the first filter unit and the second filter unit in a rotatable manner, and that The position of the second filter unit is exchanged, so that the first filter unit and the second filter unit are rotated and moved in opposite directions to each other, thereby switching the optical filters arranged in the incident light path, The filter switching mechanism includes a filter driving unit that generates a driving force for rotating the first filter unit and the second filter unit, and transmits the driving force of the filter driving unit. Gear transmission mechanisms to the first filter unit and the second filter unit, the gear transmission mechanism is provided with: a driving tooth driven by the filter driving unit A first gear provided in the first filter unit, a second gear provided in the second filter unit, and an intermediate gear, the first gear train directly meshes with the drive gear, and the second gear It meshes with the drive gear via the intermediate gear.

The second aspect of the present invention is the filter switching device described in the first aspect, wherein the first gear and the intermediate gear are shifted from each other in the tooth width direction of the driving gear to generate the driving gear Mesh, The driving gear and the second gear are shifted in the tooth width direction of the intermediate gear to mesh with the intermediate gear.

A third aspect of the present invention is an aperture device, comprising: the filter switching device described in the first or second aspect; and an aperture member that forms an aperture opening through which the incident light passes. .

A fourth aspect of the present invention is a video camera, including the aperture device described in the third aspect.

According to the present invention, it is possible to reduce the size of the filter switching device.

1‧‧‧ aperture device

2‧‧‧ Aperture substrate

3, 4‧‧‧ aperture blades

5‧‧‧ Aperture Drive

6‧‧‧ Filter switching device

7‧‧‧ divider

8‧‧‧ cover member

10‧‧‧ communication hole

11‧‧‧ opening

12a, 12b, 12c, 12d

14, 15‧‧‧ support shaft

16‧‧‧Claw

21‧‧‧ Bend

22a, 22b, 22c‧‧‧Guide groove

23‧‧‧ engagement hole

24‧‧‧ Hole

25a, 25b, 25c‧‧‧Guide groove

26‧‧‧ snap hole

27‧‧‧acting component

28, 29, 30‧‧‧ reduction gear

28a‧‧‧shaft hole

29a‧‧‧shaft hole

30a‧‧‧shaft hole

31‧‧‧First Block

32‧‧‧Second Block

33‧‧‧Drive motor

34, 35‧‧‧ Snap Pin

36a, 36b ‧‧‧ escape hole

37‧‧‧Drive gear

38‧‧‧Drive gear

39‧‧‧shaft hole

40‧‧‧ Containment Department

41, 42, 43‧‧‧ support shaft

44‧‧‧ Bracket

45‧‧‧Terminal

46‧‧‧printed circuit board

47‧‧‧Wiring

50‧‧‧ filter switching mechanism

51‧‧‧first filter unit

52‧‧‧Second filter unit

53‧‧‧ Filter switching mechanism

54‧‧‧Optical Filter

55‧‧‧ Filter support member

56‧‧‧ opening

57‧‧‧ Filter support frame

58‧‧‧ base

59‧‧‧Gear section (first gear)

60‧‧‧Shaft hole

61‧‧‧Optical Filter

62‧‧‧ Filter support member

63‧‧‧ Filter support frame

64‧‧‧ base

65‧‧‧Gear section (second gear)

66‧‧‧shaft hole

67‧‧‧ Filter driver

68‧‧‧Gear transmission mechanism

71‧‧‧rotating member

72‧‧‧ Magnet

73‧‧‧ bobbin

74‧‧‧ support member

75‧‧‧ yoke

76‧‧‧Magnet holder

77‧‧‧ arm

78‧‧‧ Gear section (drive gear)

79a, 79b‧‧‧axis

80‧‧‧ terminal

81, 82‧‧‧ support

83‧‧‧hole

84‧‧‧ relay substrate

85‧‧‧ Wiring

86‧‧‧Intermediate gear

86a‧‧‧shaft hole

91‧‧‧ opening

92a, 92b, 92c, 92d‧‧‧through holes

94‧‧‧ opening

95a, 95b, 95c, 95d‧‧‧ through holes

96a, 96b, 97‧‧‧ escape hole

98‧‧‧Mounting film

100‧‧‧Camera

101‧‧‧Mounting table

102‧‧‧Camera body

103‧‧‧Mirror tube section

104‧‧‧Object lens

105‧‧‧Photographic element

G1, G2‧‧‧step difference

1 (A) and 1 (B) are diagrams showing a configuration example of a video camera to which the present invention is applied.

FIG. 2 is an exploded perspective view when the diaphragm device according to the embodiment of the present invention is viewed obliquely from below.

FIG. 3 is an exploded perspective view illustrating a configuration example of the diaphragm driving section.

FIG. 4 is an exploded perspective view illustrating a configuration of a filter driving section.

FIG. 5 is a perspective view showing the configuration of each gear of the gear transmission mechanism.

FIG. 6 is a schematic diagram showing the relative positional relationship of the height directions of the gears of the gear transmission mechanism.

FIG. 7 is a perspective view showing a first configuration state of the filter switching device.

FIG. 8 is a perspective view showing the positional relationship of each part in the first arrangement state.

FIG. 9 is an arrow E view of FIG. 8.

FIG. 10 is a perspective view showing a second configuration state of the filter switching device.

FIG. 11 is a perspective view showing the positional relationship of each part in the second arrangement state.

FIG. 12 is an arrow F view of FIG. 11.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

<Construction of Camera>

First, the structure of a video camera will be described.

Fig. 1 shows a configuration example of a camera to which the present invention is applied, (A) is an external view of the entire camera, and (B) is a schematic view of the inside of a lens barrel. The illustrated camera 100 is, for example, a surveillance camera installed on a ceiling portion (or a wall, a pillar, or the like) of a building for the purpose of preventing theft. The camera 100 includes a mounting table 101 and a camera body 102. The mounting table 101 is, for example, a structure that is fixed to a ceiling portion of a building by bolt fastening.

The camera body 102 includes a lens barrel portion 103 and an objective lens 104. An optical system including an objective lens 104 is incorporated in the lens barrel portion 103. The objective lens 104 is attached to the front end of the lens barrel portion 103. In addition, a diaphragm device 1 and a photographing element 105 as a functional part of the optical system are incorporated in the camera body 102. The aperture device 1 forms an aperture opening in the middle of a path (hereinafter, referred to as an “incident light path”) of light (hereinafter, referred to as “incident light”) incident on the lens barrel portion 103, and adjusts this aperture opening Size, adjust the amount of incident light.

The imaging element 105 is an imaging element capable of color photography, and is composed of, for example, a CCD (Charge Coupled Device) imaging element, a CMOS (Complementary Metal Oxide Semiconductor) imaging element, and the like. The imaging element 105 has, for example, an imaging surface in which a plurality (majority) of pixels are arranged in a matrix. The imaging element 105 is used to switch the incident light that is incident on the imaging surface through the aperture opening of the diaphragm device 1 into an electrical signal. The photoelectric switching element is incorporated as an example.

In addition, the present invention is not limited to the camera 100 exemplified here, and can also be applied to a camera having another configuration including the diaphragm device 1. In addition, as the configuration of the optical system, various changes such as the type, the number of lenses, the arrangement, and the arrangement of the diaphragm device 1 can be made.

<Configuration of Aperture Device>

Next, the structure of the diaphragm device will be described.

FIG. 2 is an exploded perspective view when the diaphragm device according to the embodiment of the present invention is viewed obliquely from below. Here, in the thickness direction of the diaphragm device, a side on which an aperture driving section described later is mounted is set as an upper side (upper side), and a side on which the diaphragm blade is mounted is set as a lower side (lower side).

The diaphragm device 1 shown in the figure is roughly constituted by a diaphragm substrate 2, a pair of (two) diaphragm blades 3 and 4, a diaphragm driving unit 5, a filter switching device 6, a partition plate 7, and a cover member 8.

<Iris substrate>

The diaphragm substrate 2 is a member serving as a base on which the members constituting the diaphragm device 1 are mounted. The pair of aperture blades 3 and 4 are provided as an example of an aperture member forming an aperture opening through which incident light passes. The pair of aperture blades 3 and 4 form an aperture opening in a state of overlapping each other. If the size of the aperture opening is relatively large, the amount of light (incident light) passing through the opening is relatively increased. If the size of the aperture opening is relatively small, the amount of light passing through the opening is relatively reduced. The filter switching device 6 is a person who switches an optical filter arranged in an incident light path through which incident light passes. In order to adjust the size of the aperture opening, the aperture driving unit 5 moves a pair of aperture blades 3 and 4 relatively. Hereinafter, the configuration of each part will be described in detail.

The diaphragm substrate 2 is made of, for example, a resin. In the thickness direction of the aperture substrate 2, the side on which the pair of aperture blades 3, 4 is mounted becomes the lower surface side of the aperture substrate 2. A communication hole 10 and an opening 11 through which incident light passes are formed in the diaphragm substrate 2. The opening portion 11 is formed in a circular shape in a state penetrating the thickness direction of the diaphragm substrate 2. In addition, four pins 12a, 12b, 12c, 12d, and two support shafts 14, 15 are provided on the lower side of the aperture substrate 2. The four pins 12a, 12b, 12c, and 12d are for separating the aperture blades 3, 4, and The spacer 7 and the cover member 8 are used by mounting the diaphragm substrate 2. The support shafts 14 and 15 are used for mounting a constituent member (described later) of the filter switching device 6 on the diaphragm substrate 2. In addition, claw portions 16 are provided on the outer peripheral portion of the diaphragm substrate 2 at four locations. The claws 16 are used to attach the cover member 8 to the diaphragm substrate 2.

(Aperture Blade)

The pair of aperture blades 3 and 4 is made of, for example, a material having a carbon film covering the surface of a plate-shaped raw material containing polyethylene terephthalate to make it conductive. Each of the aperture blades 3 and 4 is formed in a thin plate shape as a whole.

An aperture blade 3 is provided with a bent portion 21, three guide grooves 22 a, 22 b, and 22 c, and an engaging hole 23. The bent portion 21 is bent into a substantially U-shape as a whole, and a part thereof is cut into a V-shape. An ND (Neutral Density) filter (not shown) is attached to a part of the curved portion 21 (a cut-out portion of a V-shape). The three guide grooves 22a, 22b, and 22c are formed in parallel with each other along the longitudinal direction of the diaphragm blade 3. Two of the three guide grooves 22a, 22b, and 22c are formed on the same straight line. A remaining one of the guide grooves 22c is formed in the edge portion opposite to the two guide grooves 22a and 22b across the curved portion 21. The engaging hole 23 is formed on an extension line of the two guide grooves 22a and 22b. In addition, the engaging hole 23 is formed to be long in a plan view along the short side direction of the diaphragm blade 3. Hole-like.

The other aperture blade 4 is provided with a hole portion 24, three guide grooves 25a, 25b, 25c, and an engaging hole 26. The hole portion 24 is formed in a circular shape approximately as a whole, and a part of the hole portion 24 is cut into a V shape. An ND filter (not shown) is attached to a portion of the hole portion 24 (a V-shaped cut-out portion). The aperture portion 24 is formed with an aperture opening by overlapping with the bent portion 21 described above. The three guide grooves 25a, 25b, and 25c are formed in parallel with each other along the longitudinal direction of the diaphragm blade 4. Two of the three guide grooves 25a, 25b, and 25c are formed on the same straight line. A remaining one of the guide grooves 25c is formed at an edge portion on the opposite side of the two guide grooves 25a and 25b across the hole portion 24. The engaging holes 26 are formed on the extension lines of the two guide grooves 25a and 25b. The engaging hole 26 is formed in a long hole shape in plan view along the short side direction of the diaphragm blade 4.

(Aperture drive section)

The aperture driving unit 5 is a person who moves the aperture blades 3 and 4 in opposite directions when adjusting the size of the aperture opening formed by the two aperture blades 3 and 4. As shown in FIG. 3, the diaphragm driving unit 5 is configured using an operating member 27, three reduction gears 28, 29, and 30, a first seat member 31, a second seat member 32, and a drive motor 33.

(Acting member)

The actuating member 27 is an operator that moves a pair of aperture blades 3 and 4 in opposite directions to each other. The actuating member 27 is formed, for example, by one-piece molding of a resin. A pair of engagement pins 34 and 35 (FIG. 2), a pair of release holes 36 a and 36 b, a driving gear 38, and a shaft hole 39 are integrally formed in the operating member 27. A shaft hole 28 a is provided at the center of the reduction gear 28. Similarly, a shaft hole 29 a is provided in the reduction gear 29, and a shaft hole 30 a is provided in the reduction gear 30. The three reduction gears 28, 29, and 30 each have two gear portions of two sizes arranged in two stages. In addition, a small-diameter gear portion (not shown) of the reduction gear 28 meshes with the drive gear 38, and a large-diameter gear portion of the reduction gear 28 meshes with a small-diameter gear portion (not shown) of the reduction gear 29. In addition, the large-diameter gear portion of the reduction gear 29 is meshed with the small-diameter gear portion of the reduction gear 30, and the large-diameter gear portion of the reduction gear 30 is meshed with the drive gear 37. The driving gear 37 is mounted on a rotation shaft of the driving motor 33. The drive motor 33 is configured using, for example, a stepping motor.

The first base member 31 and the second base member 32 are installed in the receiving portion 40 of the diaphragm substrate 2. The accommodating portion 40 of the diaphragm substrate 2 is formed in a box shape, and three support shafts 41, 42, 43 are provided in the box body. The first member 31 is configured to be detachable from the receiving portion 40 of the diaphragm substrate 2. The second seat member 32 is configured to be detachable from the first seat member 31. The drive motor 33 is mounted on the second seat member 32 using a bracket 44. A printed circuit board 46 is mounted on the terminal portion 45 of the drive motor 33 by soldering. A terminal-attached wiring 47 is mounted on the printed circuit board 46 by soldering.

The configuration of the diaphragm driving unit 5 is basically similar to that described in Japanese Patent Laid-Open No. 2013-109253.

(Configuration of filter switching device)

The filter switching device 6 includes: a first filter unit 51 and a second filter unit 52, each of which has an optical filter that can be arranged on an incident light path through which incident light passes; and a filter switching mechanism 53 that can The first filter unit 51 and the second filter unit 52 are rotatably supported, and the positions of the first filter unit 51 and the second filter unit 52 are exchanged before and after the rotation movement. The filter unit 51 and the second filter unit 52 face each other. Rotate in the opposite direction to switch the optical filter placed on the incident light path.

(Filter unit)

The first filter unit 51 and the second filter unit 52 have basically similar structures. Therefore, the configuration of the first filter unit 51 will be described in detail here.

The first filter unit 51 is configured using an optical filter 54 and a filter support member 55 that supports the optical filter 54. The optical filter 54 includes, for example, a square (a square in the illustration) glass substrate on a substrate. Considering the processing time in the case of obtaining a plurality of optical filters 54 from a large-sized glass substrate that is a mother plate of the optical filter 54, it is preferable that the shape of the optical filter 54 is rectangular. However, the shape of the optical filter 54 is not limited to this. For example, the shape of the optical filter 54 may be a circle or a polygon other than a square.

The filter support member 55 is obtained by molding, for example, a single body of resin. A circular opening 56 is formed on the filter support member 55 in a state where the filter support member 55 penetrates the filter support member 55. This opening 56 is used for passing incident light as a subject of the filter ring. Therefore, the optical filter 54 is attached in a state where the opening portion 56 is closed. The optical filter 54 is fixed to one side of the filter support member 55 using, for example, an adhesive.

A filter support frame 57, a base portion 58 and a gear portion 59 are integrally formed on the filter support member 55. A step (depression) is provided on one side of the filter support frame 57 so as to surround the opening portion 56, and an optical filter 54 is mounted on the step. The optical filter 54 is housed in the step of the filter support frame 57 so as not to protrude in the thickness direction of the filter support frame 57. In addition, the base portion 58 of the filter support member 55 is formed in a fan shape, and a gear portion 59 is formed in an arc portion of the fan shape. The filter support frame 57 extends from the filter support frame 57 to the base portion 58 and is formed equally flat except for the above-mentioned step difference. In contrast, the base portion 58 and the gear portion 59 are formed such that the gear portion 59 protrudes in the thickness direction of the filter support member 55. Structure with stages. The teeth of the gear portion 59 are arranged in a state where the teeth of the gear portion 59 protrude more outward than the arc-shaped portions constituting the base portion 58. A shaft hole 60 is formed in the base portion 58 as a fulcrum when the filter unit 51 is rotated. The pitch circle of the arc portion of the base portion 58 and the teeth of the gear portion 59 are centered around the shaft hole 60, respectively.

Similarly, the second filter unit 52 is configured using an optical filter 61 and a filter support member 62 that supports the optical filter 61. In addition, a filter support frame 63, a base portion 64, and a gear portion 65 are integrally formed on the filter support member 62. A shaft hole 66 is formed in the base portion 64 of the filter support member 62.

The two filter units 51 and 52 are mounted on the diaphragm substrate 2 with the filter mounting surfaces facing each other. At this time, the gear portion 59 of the filter support member 55 and the gear portion 65 of the filter support member 62 are disposed facing outward, respectively. That is, the gear portion 59 is disposed so as to protrude from the cover member 8 side, and the gear portion 65 is disposed so as to protrude from the partition plate 7 side.

The combination of the optical filters 54 and 61 used in the above-mentioned two filter units 51 and 52 can be considered as various combinations. As an example here, an optical filter 54 is formed by an infrared blocking filter, and a false filter is used. The mirror constitutes another optical filter 61. The infrared blocking filter is a filter that blocks infrared rays from incident light. The dummy filter is a filter (light path length correction filter) used for light path length correction. Specifically, the dummy filter is a light path length when an optical filter (in this example, an infrared blocking filter) is used in combination with the incident light path, and the dummy filter is placed in the incident light path. When the length of the light path becomes equal, the length of the light path is corrected.

(Filter switching mechanism)

The filter switching mechanism 53 includes a filter driving unit 67 (FIG. 4) that generates a driving force for rotating the first filter unit 51 and the second filter unit 52; and The gear transmission mechanism 68 (FIG. 2 and FIG. 5) transmits the driving force of the filter driving unit 67 to the first filter unit 51 and the second filter unit 52.

(Filter driver)

As shown in FIG. 4, the filter driving section 67 is configured using a rotating member 71, a magnet 72, a bobbin 73, a coil (not shown), a support member 74, and a yoke 75. A magnet holder portion 76, an arm portion 77, and a gear portion 78 are integrally formed on the rotating member 71. The magnet holder portion 76 is a portion that holds the magnet 72. On the upper and lower sides of the magnet holder portion 76, shafts 79a and 79b are provided coaxially, respectively (FIG. 5). These shafts 79 a and 79 b serve as the center of rotation of the rotating member 71. The arm portion 77 extends in an L shape from the lower end of the magnet holder portion 76, and a gear portion 78 is formed at the extended end thereof. The gear portion 78 is formed in an arc shape. The arm portion 77 is connected to the middle portion of the arc of the gear portion 78.

The magnet 72 is configured using a rectangular permanent magnet. The reason for using a rectangular permanent magnet as the magnet 72 is that it is more advantageous in terms of cost and ease of processing compared with the use of a cylindrical permanent magnet. However, in the implementation of the present invention, the shape of the permanent magnet is not limited to a specific shape. The magnet 72 is assembled to the magnet holder portion 76 in a fixed state. In this assembled state, the virtual shafts connecting the upper and lower shafts 79 a and 79 b are arranged so as to pass through the center of the magnet 72.

The bobbin 73 is mainly formed of an insulating material such as resin. Four terminals 80 are provided on the upper end of the bobbin 73. A coiled wire terminal is connected to the terminal 80. The coil is wound around the bobbin 73 so as to surround the magnet holder portion 76 holding the magnet 72. The support member 74 includes two support pieces 81 and 82 and is mounted on the bobbin 73 by using the support pieces 81 and 82 to hold the upper portion of the coil. A hole (not shown) is provided in the supporting piece 82 of the supporting member 74, and corresponding to this, it is also at the bottom of the winding shaft 73 The section is also provided with a hole 83. A shaft 79 a of the magnet holder portion 76 is inserted into the hole of the support piece 82, and a shaft 79 b of the magnet holder portion 76 is inserted into the hole 83 of the bobbin 73. Thereby, the rotation member 71 is rotatably supported by the bobbin 73 and the support member 74.

The yoke 75 suppresses leakage of magnetic field lines to the outside. The yoke 75 is formed in a cylindrical shape. The yoke 75 accommodates a bobbin assembly including a rotating member 71, a magnet 72, a bobbin 73, a coil, a support member 74, and the like. However, in a state where the bobbin assembly is housed in the yoke 75, the arm portion 77 and the gear portion 78 of the rotating member 71 are arranged to protrude from the yoke 75.

A relay substrate 84 is mounted on the upper end of the yoke 75. The relay substrate 84 is formed of a circular printed circuit board corresponding to the diameter of the yoke 75. The above-mentioned four terminals 80 and the wiring 85 with a connector are soldered to the relay substrate 84, respectively. The relay substrate 84 is electrically connected to a coil wound around a bobbin 73 and a filter control unit (not shown). The filter control unit causes a current to flow through the coil based on a predetermined condition. If a current flows through the coil, a magnetic force is generated. This magnetic force is used as a driving force for rotating the two filter units 51 and 52. In addition, if a magnetic force is generated by applying current to the coil, the rotating member 71 performs a rotating operation by using the magnetic force. At this time, the direction in which the rotating member 71 is rotated is changed according to the direction of the current flowing through the coil. Therefore, in the filter control section, the direction of rotation of the rotating member 71 can be switched by reversing the polarity (positive electrode, negative electrode) when a current flows through the coil.

The filter driving section 7 including the above-mentioned configuration is mounted on the receiving section 20 (FIG. 4) of the diaphragm substrate 2 in a positional relationship adjacent to the diaphragm driving section 5. At this time, the gear portion 78 of the rotating member 71 is disposed so as to protrude from the lower surface side of the diaphragm substrate 2 through the communication hole 10 (FIG. 2).

(Gear transmission mechanism)

The gear transmission mechanism 68 is substantially composed of four gears. Specifically, the gear transmission mechanism 68 is composed of the above-mentioned three gear portions 59, 65, 78, and the intermediate gear 86. Among them, the gear portion 59 corresponds to a first gear, the gear portion 65 corresponds to a second gear, and the gear portion 78 corresponds to a driving gear. The intermediate gear 86 is composed of a flat gear. A shaft hole 86a is provided at the center of the intermediate gear 86.

FIG. 5 is a perspective view showing the configuration of each gear of the gear transmission mechanism. In addition, FIG. 6 is a schematic diagram showing the relative positional relationship in the height direction of each gear of the gear transmission mechanism. As shown in the figure, the gear portion 59 integrally provided in the filter unit 51 directly meshes with the gear portion 78. The gear portion 65 integrally provided in the filter unit 52 is meshed with the gear portion 78 via the intermediate gear 86. The gear portion 59 and the intermediate gear 86 are meshed with the gear portion 78 at positions shifted in the tooth width direction of the gear portion 78. Therefore, in the tooth width direction of the gear portion 78, a step difference G1 is secured between the gear portion 59 and the intermediate gear 86. With this gap G1, even when the gear portion 59 and the intermediate gear 86 overlap with each other in plan view during the operation of the gear transmission mechanism 68, interference (contact) between the two can be avoided. The gear portion 59 and the intermediate gear 86 mesh with the gear portion 78 at different positions in the circumferential direction of the gear portion 78. The intermediate gear 86 is simultaneously meshed with the gear portion 65 and the gear portion 78. In addition, the gear portion 65 and the gear portion 78 are meshed with the intermediate gear 86 at positions shifted in the tooth width direction of the intermediate gear 86. Therefore, in the tooth width direction of the intermediate gear 86, a step difference G2 is secured between the gear portion 65 and the gear portion 78. With this gap G2, even when the gear portion 65 and the gear portion 78 overlap in plan view during the operation of the gear transmission mechanism 68, interference (contact) between the two can be avoided.

(Partition plate)

The partition plate 7 is formed in a thin plate shape. The partition plate 7 is, for example, similar to the diaphragm blades 3 and 4 described above. Similarly, it is configured by using a carbon film to cover the surface of a plate-shaped raw material containing polyethylene terephthalate to make it conductive. The partition plate 7 is disposed between the diaphragm blades 3 and 4 and the filter units 51 and 52 in the thickness direction of the diaphragm substrate 2.

The partition plate 7 is formed with an opening portion 91 and four through holes 92a, 92b, 92c, and 92d. The opening portion 91 is formed in a circular shape while penetrating the partition plate 7. When the partition plate 7 is attached to the diaphragm substrate 2, the opening portion 91 is arranged concentrically with the opening portion 11 of the diaphragm substrate 2. The four through holes 92a, 92b, 92c, and 92d are fitted to four pins 12a, 12b, 12c, and 12d provided on the diaphragm substrate 2, respectively.

(Cover member)

The cover member 8 is obtained by molding a single body such as resin. The cover member 8 is attached to the lower surface side of the diaphragm substrate 2. At this time, the diaphragm blades 3 and 4, the partition plate 7, and the filter units 51 and 52 are housed between the diaphragm substrate 2 and the cover member 8. The cover member 8 is formed with an opening portion 94, four through holes 95a, 95b, 95c, and 95d and escape holes 96a, 96b, and 97. The opening portion 94 is formed in a circular shape while penetrating the cover member 8. When the cover member 8 is attached to the diaphragm substrate 2, the opening portion 94 is arranged concentrically with the opening portion 11 of the diaphragm substrate 2. The four through holes 95a, 95b, 95c, and 95d are fitted to four pins 12a, 12b, 12c, and 12d provided on the diaphragm substrate 2, respectively. The escape holes 96 a and 96 b are used by the user to avoid interference with the engaging pins 34 and 35 of the actuating member 27. The escape hole 97 is used by the user to avoid interference with the gear portion 78 of the rotating member 71. In addition, four mounting pieces 98,... Are formed on the outer peripheral portion of the cover member 8. Each of the mounting pieces 98,... Is locked to each of the claw portions 16,... Provided on the diaphragm substrate 2.

<Explanation of the mounting state of the constituent members>

Next, the mounting state of the constituent members of the diaphragm device 1 will be described.

Two aperture blades 3 and 4, a partition plate 7, two filter units 51 and 52, an intermediate gear 86, and a cover member 8 are mounted on the lower surface side of the aperture substrate 2. Further, an aperture driving section 5 and a filter driving section 67 are mounted on the upper surface side of the aperture substrate 2.

When the diaphragm blade 3 is mounted on the diaphragm substrate 2, the guide grooves 22 a, 22 b, and 22 c of the diaphragm blade 3 are fitted to the pins 12 a, 12 c, and 12 d of the diaphragm substrate 2.

When the diaphragm blade 4 is mounted on the diaphragm substrate 2, the guide grooves 25 a, 25 b, and 25 c of the diaphragm blade 4 are fitted to the pins 12 a, 12 b, and 12 c of the diaphragm substrate 2.

When the partition plate 7 is mounted on the diaphragm substrate 2, the through holes 92 a, 92 b, 92 c, and 92 d of the partition plate 7 are fitted to the pins 12 a, 12 b, 12 c, and 12 d of the diaphragm substrate 2.

When the two filter units 51 and 52 are mounted on the diaphragm substrate 2, the shaft hole 60 of the first filter unit 51 and the shaft hole 66 of the second filter unit 52 are respectively fitted and locked to the diaphragm substrate 2. Of the support shaft 14.

When the intermediate gear 86 is mounted on the diaphragm substrate 2, the shaft hole 86 a of the intermediate gear 86 is fitted and locked to the support shaft 15 of the diaphragm substrate 2. At this time, the intermediate gear 86 is meshed with the gear portion 65.

When the cover member 8 is mounted on the diaphragm substrate 2, the mounting pieces 98,... Of the cover member 8 are locked to the claw portions 16,... Of the diaphragm substrate 2, respectively.

In a case where the diaphragm driving portion 5 is mounted on the diaphragm substrate 2, an operating member 27 and three reduction gears 28, 29, and 30 are installed in the receiving portion 40 of the diaphragm substrate 2, and a first seat member 31 is installed from above. At this time, the shaft holes 39 of the actuating member 27 are fitted into the support while the support shafts 42 and 43 pass through the escape holes 36 a and 36 b of the actuating member 27. On the shaft 41. Further, the shaft hole 29 a of the reduction gear 29 is fitted to the support shaft 41 so that the reduction gear 29 is superposed on the operation gear 38 of the operation member 27. In addition, the engagement pins 34 and 35 of the actuating member 27 are made to protrude from the lower surface side of the diaphragm substrate 2. Then, the engaging pin 34 is engaged with the engaging hole 23 of the diaphragm blade 3, and the engaging pin 35 is engaged with the engaging hole 26 of the diaphragm blade 4. Further, the shaft hole 28 a of the reduction gear 28 is fitted into the support shaft 42, and the shaft hole 30 a of the reduction gear 30 is fitted into the support shaft 43.

In a case where the filter driving section 67 is mounted on the diaphragm substrate 2, a yoke 75 containing the rotating member 71, the magnet 72, and the like is mounted on the upper surface side of the diaphragm substrate 2. At this time, the arm portion 77 and the gear portion 78 of the rotating member 71 are passed through the communication hole 10 (FIG. 2) of the diaphragm substrate 2 to protrude below the diaphragm substrate 2. The gear portion 78 is meshed with the gear portion 59 and the intermediate gear 86.

In this way, by mounting each constituent member of the aperture device 1 on the aperture substrate 2, the two aperture blades 3, 4 are supported by the pins 12a, 12b, 12c, and 12d so as to be linearly movable. The two filter units 51 and 52 are rotatably supported around the support shaft 14, and the intermediate gear 86 is rotatably supported around the support shaft 15.

Next, the operation of the diaphragm device 1 will be described. The operation of the aperture device 1 includes an aperture adjustment operation and a filter switching operation. Hereinafter, each operation will be described in order.

<Explanation of Iris Adjustment Action>

First, the aperture adjustment operation will be described. The aperture adjustment operation is an operation of changing the size of the aperture opening formed by the pair of aperture blades 3 and 4. More specifically, the aperture adjustment operation refers to an operation of adjusting the size of the aperture opening by relatively moving the pair of aperture blades 3 and 4. The action of adjusting the size of the aperture opening in the aperture device 1 is related to The operation of adjusting the amount of incident light in a surveillance camera or the like having the diaphragm device 1 is substantially the same.

Actually, when the size of the aperture opening is adjusted by the aperture device 1, the drive motor 33 of the aperture driving section 5 is driven. Then, the driving force of the drive motor 33 is transmitted to the actuating gear 38 from the driving gear 37 via the reduction gear 30, the reduction gear 29, and the reduction gear 28. Then, the operating member 27 is rotated in accordance with the driving of the driving motor 33.

In addition, when the actuating member 27 rotates, the aperture blades 3 and 4 engaged with the engaging pins 34 and 35 of the actuating member 27 move linearly simultaneously in the longitudinal direction of the aperture substrate 2. At this time, the direction in which the diaphragm blade 3 moves and the direction in which the diaphragm blade 4 moves are opposite to each other. In this way, if the pair of aperture blades 3 and 4 are moved relatively, the size of the aperture opening formed by the overlap of the aperture blades 3 and 4 changes. Therefore, the size of the aperture opening can be adjusted by changing the rotation amount and the rotation direction of the drive motor 33.

<Description of Filter Switching Action>

Next, the filter switching operation will be described.

The filter switching operation refers to the operation of switching the optical filters (54, 61) arranged on the incident light path. More specifically, the filter switching action refers to an action of switching the configuration state of the optical filters 54 and 61 from the first configuration state to the second configuration state, or from the second configuration state to the first configuration state. The first arrangement state refers to a state in which the optical filter 54 is arranged on the incident light path through the aperture opening, and the optical filter 61 is retracted from the incident light path. The second arrangement state refers to a state where the optical filter 61 is disposed on the incident light path and the optical filter 54 is retracted from the incident light path.

Here, in the above-mentioned first arrangement state, as shown in FIG. 7, the optical filter 54 of the first filter unit 51 is placed in and out of the opening portion 11 (FIG. 2) of the diaphragm substrate 2. In addition, the optical filter 61 of the second filter unit 52 is disposed while retracting from the opening 11. FIG. 8 is a perspective view showing the positional relationship of each part in the first configuration state, and FIG. 9 is an arrow E view of FIG. 8. When the arrangement state of the optical filters 54 and 61 is switched from the first arrangement state to the second arrangement state, the gear portion 78 is rotated counterclockwise from the state shown in FIG. 9. Then, the intermediate gear 86 and the gear portion 59 rotate in a clockwise direction, and the gear portion 65 rotates in a counterclockwise direction. In addition, the first filter unit 51 rotates clockwise around the support shaft 14 as a center, and the second filter unit 52 rotates counterclockwise around the support shaft 14 as a center. As a result, the position of the first filter unit 51 and the position of the second filter unit 52 are exchanged.

On the other hand, in the above-mentioned second arrangement state, as shown in FIG. 10, the optical filter 61 of the second filter unit 52 is placed in and out of the opening 11 (FIG. 2) of the diaphragm substrate 2, and the first filter The optical filter 54 of the mirror unit 51 is disposed while retracting from the opening 11. FIG. 11 is a perspective view showing the positional relationship of each part in the second arrangement state. FIG. 12 is an arrow F view of FIG. 11. When the arrangement state of the optical filters 54 and 61 is switched from the second arrangement state to the first arrangement state, the gear portion 78 is rotated clockwise from the state of FIG. 12. Then, the intermediate gear 86 and the gear portion 59 rotate in the counterclockwise direction, and the gear portion 65 rotates in the clockwise direction. In addition, the first filter unit 51 rotates counterclockwise around the support shaft 14 as a center, and the second filter unit 52 rotates clockwise around the support shaft 14 as a center. As a result, the position of the first filter unit 51 and the position of the second filter unit 52 are exchanged.

When the optical devices 54 and 61 arranged in the incident light path are actually switched by the diaphragm device 1, the following filter switching operation is performed. That is, a magnetic field is formed by applying current to a coil provided in the filter driving section 67. Then, the rotating member 71 rotates in accordance with the direction and intensity of the magnetic field formed by applying current to the coil, and the rotation thereof The driving force is transmitted to each of the filter units 51 and 52 via a gear transmission mechanism 68. Specifically, the rotational driving force of the rotating member 71 is transmitted from the gear portion 78 to the gear portion 59 using the gear portion 78 as a common driving gear, and from the gear portion 78 to the gear portion via the intermediate gear 86 65. At this time, the driving force of the self-rotating member 71 toward the first filter unit 51 is transmitted by two gears (59, 78), and the driving force of the self-rotating member 71 toward the second filter unit 52 is transmitted. , Is carried out by 3 gears (65, 78, 86). Therefore, the two filter units 51 and 52 are rotated around the support shaft 14 in opposite directions from each other. The positions of the optical filters 54 and 61 of the two filter units 51 and 52 are exchanged before and after the rotation.

In the above-mentioned filter switching operation, the teeth of the gear portion 59 and the teeth of the gear portion 65 are moved back and forth in a state where the positions are staggered up and down on the same circular orbit with the support shaft 14 as the center. In addition, the teeth of the gear portion 59 and the teeth of the intermediate gear 86 are overlapped in plan view during the filter switching operation, but they are staggered without interference due to the existence of the step difference G1 shown in FIG. 6 described above. In addition, the teeth of the gear portion 65 and the teeth of the gear portion 78 are overlapped in plan view during the filter switching operation, but they are staggered without interference due to the existence of the step difference G2 shown in FIG. Therefore, the four gears (59, 65, 78, 86) constituting the gear transmission mechanism 68 can be smoothly operated. In addition, the gear transmission mechanism 68 can reliably transmit the driving force of the filter driving unit 67 to the two filter units 51 and 52.

<Effect of Implementation Form>

According to the embodiment of the present invention, the following effects can be obtained in comparison with the invention previously filed by the applicant of the present application (Japanese Patent Application No. 2012-220064).

That is, the configuration of the gear transmission mechanism 68 that transmits the driving force of the filter driving unit 67 to the two filter units 51 and 52 is different from that in the invention of the previous application. With three intermediate gears, according to the above embodiment, only one intermediate gear 86 may be used. Therefore, it is possible to reduce the number of parts of the gear transmission mechanism 68 and save space. In addition, since the number of gears constituting the gear transmission mechanism 68 is reduced, the influence of the backlash is reduced.

In the above embodiment, the meshing position of the gear portion 59 and the intermediate gear 86 with respect to the gear portion 78 is shifted in the tooth width direction of the gear portion 78, and the gear portion 78 and the gear are shifted in the tooth width direction of the intermediate gear 86. The meshing position of the portion 65 with respect to the intermediate gear 86 is shifted. Therefore, the gears constituting the gear transmission mechanism 68 can be prevented from interfering with each other, and the gears (59, 65, 78, 86) can be densely arranged. This makes it possible to reduce the size and thickness of the filter switching mechanism 53 including the gear transmission mechanism 68.

In addition, for reference, the effects obtained by the applicant of the present invention are described below.

In the above-mentioned embodiment, a configuration is adopted in which the optical filters 54 and 61 arranged in the incident light path are switched by exchanging the positions of the two filter units 51 and 52. Therefore, compared with the conventional configuration, the filter can be reduced Space for mirror switching. That is, as is conventionally known, if a configuration is adopted in which a filter support member in which two optical filters are arranged next to each other and mounted is moved, as a space for filter switching, it is actually necessary to arrange and arrange only three optical filters. space. In contrast, as in the present embodiment, in the configuration in which the positions of the first filter unit 51 and the second filter unit 52 are exchanged before and after the rotation movement, as a space for filter switching, substantially only the arrangement is required. The space of the two optical filters 54 and 61 is sufficient. Therefore, the space for filter switching can be reduced as compared with the conventional one. As a result, the size of the diaphragm device 1 can be reduced. In particular, in the case where it is necessary to increase the size of the imaging element as a countermeasure against a high resolution of a surveillance camera, etc., and to ensure a large diameter of the aperture opening in conjunction with this, it is not necessary to increase the aperture device 1 extremely. , You can enlarge the maximum diameter of the aperture opening.

In the conventional structure, when an impact force is applied to the diaphragm substrate Next, the magnetic force of the magnet is often used to apply force to the filter support member in one direction, so that the filter support member does not move accidentally due to the impact force (dislocation). Therefore, in the case where the optical filter is switched by the movement of the filter support member, in order to apply a larger moving force than the magnetic force to the filter support member, it is necessary to supply a certain degree to the filter driving section (coil, etc.). The maximum operating voltage.

In contrast, in the embodiment described above, when an impact force is applied to the diaphragm substrate 2, the impact force works as follows. That is, the impact force applied to the diaphragm substrate 2 acts, for example, in a direction that assists the movement of the first filter unit 51 and acts in a direction that prevents the movement of the second filter unit 52. The reason is as follows. First, when an impact force is applied to the diaphragm substrate 2 in a direction parallel to the moving direction of the diaphragm blades 3 and 4, a movement force is applied to each of the filter units 51 and 52 in a rotation direction centered on the support shaft 14. At this time, each of the filter units 51 and 52 receives a movement force of approximately the same magnitude in the same direction, but the gears of the gear transmission mechanism 68 mesh with each other to prevent movement in the same direction. Therefore, even if an impact force is applied to the diaphragm substrate 2, the movement of the filter units 51 and 52 can be suppressed. This can reduce the magnetic force (capacity) of the magnet. In addition, even if the magnetic force of the magnet is not used depending on the situation, the required impact resistance can be ensured. As a result, the optical filter can be switched with a smaller operating voltage than conventionally. In addition, it is possible to reduce power consumption while ensuring the necessary impact resistance.

In the above-mentioned embodiment, since the two filter units 51 and 52 having the common support shaft 14 as the rotation center are rotatably supported, the operation of each filter unit 51 and 52 becomes compact. Therefore, it can help to minimize the space for filter switching. In addition, since the configuration in which the two filter units 51 and 52 are moved using the gear transmission mechanism 68 is adopted, the configuration of the drive system becomes very compact.

In the above embodiment, a pair of aperture blades 3, 4 and 2 filters are used. A partition plate 7 is arranged between the elements 51 and 52 to avoid interference (contact) of these positions. Therefore, by placing the partition plate 7 in the middle, the diaphragm blades 3 and 4 and the filter units 51 and 52 can be arranged close to each other. On the other hand, in the case where the partition plate 7 is not provided, in order to avoid interference between the aperture blades 3 and 4 and the filter units 51 and 52, it is necessary to arrange them in a relatively large space. Therefore, when the partition plate 7 is provided, the total thickness can be made thinner than when the partition plate 7 is not provided. In particular, with the increase in the resolution of surveillance cameras and the like, in the case where a single focus lens or the like (a so-called glare lens) is used in this optical system, it is necessary to arrange it on the front side (the subject side) of the aperture opening of the aperture device 1 The lens and the lens arranged on the rear side are arranged close to each other. Therefore, in the diaphragm device 1, it is very effective to reduce the thickness of the vicinity of the diaphragm opening interposed between the lenses.

<Modifications, etc.>

The technical scope of the present invention is not limited to the above-mentioned embodiments, and various modifications and improvements are added as long as the specific effects obtained by the constituent elements and combinations of the invention can be derived.

For example, in the above-mentioned embodiment, the gear portion 59 is integrally formed on the filter support member 55, but it is not limited to this. The filter support member 55 and the gear portion 59 may be different members, and the gear may be made of an adhesive or the like The portion 59 is fixed to a configuration of the filter support member 55. This is similar to the filter support member 62 and the gear portion 65.

In addition, the combination of optical filters as the switching target is not limited to the combination of different types of optical filters, but may also be the combination of the same type of optical filters (only the respective optical characteristics are set to be different).

In addition, the filter switching device of the present invention can be widely applied to various optical devices including an aperture device and a camera.

Claims (3)

A filter switching device, comprising: a first filter unit and a second filter unit, each of which has an optical filter, and these optical filters can be arranged in an incident light path through which incident light passes; and The filter switching mechanism supports the first filter unit and the second filter unit in a rotatable manner, and positions the first filter unit and the second filter unit before and after the rotary movement. In the exchange method, the first filter unit and the second filter unit are rotated and moved in opposite directions to each other, thereby switching an optical filter disposed in the incident light path. The filter switching mechanism is provided with A filter driving unit that generates a driving force for rotating the first filter unit and the second filter unit, and transmits the driving force of the filter driving unit to the first filter unit. And the gear transmission mechanism of the second filter unit, the gear transmission mechanism is provided with a driving gear driven by the filter driving unit, and is provided in the gear A first gear of a filter unit, a second gear provided on the second filter unit, and an intermediate gear. The first gear train directly meshes with the driving gear, and the second gear train passes through the intermediate gear. It meshes with the driving gear, the first gear and the intermediate gear are shifted in the tooth width direction of the driving gear to mesh with the driving gear, and the driving gear and the second gear are coupled to the intermediate gear. The tooth width direction shifts the position to mesh with the intermediate gear. An aperture device is characterized by comprising: a filter switching device of the first patent application scope; and an aperture member formed with an aperture opening through which the incident light is generated to pass. A video camera is characterized in that it includes: an aperture device according to the second item of the patent application.