JP4218745B2 - Manual aperture device and imaging lens for CCTV camera - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a manual iris device assembled to an imaging lens and an imaging lens for a CCTV camera using the same.
[0002]
[Prior art]
The manual aperture device is incorporated in the lens barrel so as to be orthogonal to the optical axis, and adjusts the open aperture value by rotating an operation ring or the like provided on the outer periphery (hereinafter abbreviated as aperture adjustment). To do. In terms of structure, for example, a holding frame with an opening that pivotally supports a plurality of diaphragm blades, a Kikuza that operates in conjunction with each diaphragm blade by being rotated in the holding frame, An adjustment ring or the like that is connected to a part of the lens barrel and is rotatably mounted on the outer periphery of the lens barrel. By the way, this manual diaphragm device has a simple structure compared to an automatic diaphragm device, and is often used for, for example, an inexpensive imaging lens or an imaging lens that does not need to change the aperture adjustment once adjusted. A typical example of the latter is the case where it is used for a video camera for surveillance, etc., and when adjusting the CCTV camera imaging lens at an appropriate position, adjust the aperture together with the focus adjustment so that it is optimal for the use situation. Is done.
[0003]
[Problems to be solved by the invention]
However, in the conventional manual iris device, the lens barrel must be assembled together with a plurality of lens groups, which is cumbersome and contributes to an increase in the number of assembling steps. In addition, the lens group and each mechanism part had to be removed, so that it could not be performed easily.
[0004]
The present invention has been developed in view of the above background. The object is to realize a manual iris device that can be assembled to a lens barrel by a retrofitting method and a structurally simpler manual aperture device and an imaging lens for a CCTV camera using the same. Other purposes will be clarified in the following description.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, the present invention, as illustrated in the drawings, is assembled in a lens barrel so as to be orthogonal to the optical axis by an operation unit disposed outside the lens barrel. In the manual diaphragm device that operates and adjusts a plurality of diaphragm blades, an insertion portion with an opening inserted from the radial direction into the lens barrel and an extension portion with a mounting portion arranged outside the lens barrel are integrated. A holding frame formed , two diaphragm blades as the diaphragm blades slidably disposed in the holding frame, a shaft hole penetrating the extension portion, and an outer surface corresponding to the shaft hole One end side projecting into the extension portion through the shaft hole and the other end side pivotally supported via the support portion, and the rotation disposed on the support portion side. projecting around shaft axis as the operating unit And create the lever, while being disposed in the extension portion, said being connected to one end of the rotating shaft and a rotating piece that slides each diaphragm blades in different directions, the holding frame, the diaphragm blades In the state where the pivot shaft, the operation lever, and the pivot piece are assembled as a manual diaphragm device, the insertion portion of the holding frame from the notch provided on the outer periphery of the lens barrel with respect to the lens barrel Is inserted into the lens barrel and fixed through the mounting portion of the extension portion, and the diaphragm blade is adjusted by the rotation of the operation lever through the rotating shaft and the rotating piece. It is a thing.
[0006]
According to the above structure, the manual diaphragm device is unitized by the holding frame, the diaphragm blade, the pivot shaft and the pivot piece, and the operation lever, and can be assembled to the lens barrel by a retrofitting method. When this is used, a notch portion corresponding to the insertion portion of the holding frame is provided in the lens barrel of the imaging lens (for example, a CCTV camera photographing lens). Then, in a united state, the manual diaphragm device is extended by inserting the insertion portion of the holding frame into the lens barrel from the cutout portion and then fixing the mounting portion to the lens barrel side via a screw or the like. The portion is disposed so as to protrude in the outer diameter direction of the lens barrel. A rotation shaft and an operation lever are arranged on one side of the extended portion, and the diaphragm is adjusted by rotating the operation lever.
[0007]
Therefore, the product according to the present invention has the following advantages since the manual diaphragm device can be unitized in a state where it is completely separated from the lens barrel side.
First, it is not necessary to incorporate each member for the aperture device at the same time as the lens group in the lens barrel as in the conventional product, and the assembly work on the lens barrel side can be simplified. At the same time, there is no need for an adjusting ring for a diaphragm that is integrally assembled on the outer periphery of the lens barrel as in the conventional product, and the design freedom of the lens barrel itself can be obtained.
Second, since the lens barrel can be attached and detached by a retrofitting method, for example, it is possible to quickly cope with the case where it is desired to replace the manual diaphragm device by quality inspection after the final assembly.
Third, it is structurally configured with a relatively small number of parts, and can be easily deformed such that the rotating shaft and the operating lever or the rotating shaft and the rotating piece are integrally formed. It is realized mechanically easily. In addition, since it is not affected by the specifications on the lens barrel side, it can be easily adopted as a common product for different imaging lenses, and as a result, cost reduction due to mass production can be expected.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment of the present invention will be described with reference to FIGS. In addition, this form example is a suitable specific example of this invention, and does not restrict | limit the scope of the present invention.
[0009]
FIG. 1 shows an example of a diaphragm operation of a manual diaphragm device to which the present invention is applied. FIG. 1 (a) shows the closed state of the diaphragm blade, and FIG. 1 (b) shows the fully opened state of the diaphragm blade from the operation lever side. It is a model rear view. FIG. 2 shows an example of an imaging lens using the manual diaphragm device, and FIG. 3 shows the relationship between the front and rear holding cylinders of the imaging lens and the manual diaphragm device. 4 (a) and 4 (b) are views of the manual throttle device as viewed from the front and the back, and FIGS. 5 to 10 show components of the manual throttle device. Of these, FIG. 5 is a view seen from above in the state before the diaphragm blades are arranged, FIGS. 6 and 7 are the same front and rear views, FIG. 8 is a sectional view in the middle vertical direction of FIG. 6, and FIG. The diaphragm blade is shown as a single item, and FIG. 10 is a sheet metal attached to the front side of the holding frame. In these drawings, the manual diaphragm device 1 of the embodiment is developed for the imaging lens 20 for the CCTV camera of FIG. 2, and the diaphragm structure will be described in detail after the imaging lens 20 is outlined below.
[0010]
The imaging lens 20 of FIG. 2 is configured for a high-sensitivity CCTV camera. The lens barrel 21 is mainly composed of a front holding cylinder 22 and a rear holding cylinder 23, and is a screw mount portion provided at the rear of the rear holding cylinder 23. 24 is attached to the camera body side. The front holding cylinder 22 and the rear holding cylinder 23 hold the lens group L1 and the lens group L2 via the corresponding front frame 25 and the rear frame 26, and the corresponding sides have a fitting structure as shown in FIG. Connected together. That is, a large-diameter flange portion 27 is provided on the rear end side of the front holding cylinder 22, and a substantially ring-shaped holding portion 28 is provided on the end surface of the flange portion 27. The holding portion 28 is lacking the upper portion, and a corresponding portion of the manual throttle device 1 described later can be inserted from the notch portion 28a, and at the lower portion that is an inner peripheral intermediate position facing the notch portion 28a. A positioning recess 28b is provided. On the other hand, on the front end side of the rear holding cylinder 23, a large-diameter connecting portion 29 fitted to the outside of the holding portion 28 is provided. The connecting portion 29 is not provided with an upper portion corresponding to the cutout portion 28 a, covers the holding portion 28 in a state of being fitted with the holding portion 28, and a portion corresponding to the cutout portion 28 a of the end surface of the flange portion 27. Is exposed. Symbols 30 and 31 in FIG. 3 are screws. The front holding cylinder 22 and the rear holding cylinder 23 are coupled to each other by screwing a plurality of screws 30 from the mounting holes 29 a of the connecting portion 29 into the mounting holes 28 c of the holding portion 28. Is done. The manual throttle device 1 is inserted into the holding portion 28 and the connecting portion 30 from the cutout portion 28a and positioned by the recess 28b, and a screw 31 is attached to the attachment portion 12 of the holding frame 2 described later. The hole 12a is fixed by being screwed into the mounting hole 27a of the flange portion 27.
[0011]
A front frame 25 holding the lens group L1 is assembled to the front holding cylinder 22 so that the movement can be adjusted, and a rear frame 26 holding the lens group L2 is assembled to the rear holding cylinder 23 so that the movement can be adjusted. It has been. The movement adjustment of the front frame 25 and the rear frame 26 is a range shown on the upper side and the lower side in FIG. 2 and is operated by adjustment rings 32 and 33 assembled to the outer peripheries of the front holding cylinder 22 and the rear holding cylinder 23, respectively. . These movement adjusting mechanisms include a plurality of cam grooves 22a and 23a provided in the front and rear holding cylinders 22 and 23, pins 34 and 35 protruding from the front and rear frames 25 and 26, an adjustment ring 32, It consists of grooves 32a, 33a and the like provided in the inner circumferential front-rear direction of 33. Each pin 34, 35 is fitted to the corresponding groove 32a, 33a through the cam groove 22a, 23a. The front and rear frames 25 and 26 are moved along the cam grooves 22a and 23a together with the pins 34 and 35 by rotating the adjustment rings 32 and 33. This structure itself is a well-known structure, similar to the holding structure of the lens groups L1 and L2 with respect to the front and rear frames 25 and 26.
[0012]
On the other hand, the manual diaphragm device 1 which is the main part of the present invention is a support section composed mainly of a long and thin holding frame 2 and comprising a sheet metal 3, two diaphragm blades 4A and 4B, an arm section 7 and a stopper section 8. 6, a rotating piece 5, a rotating shaft 9, and an operation lever 10. Although enlarged in the drawing, the main part has a small thickness of 2 to 5 mm and a length of 25 to 40 mm.
[0013]
Among these, the holding frame 2 is a resin molded body. In terms of shape, as shown in FIGS. 5 to 8, the lower side is an insertion portion 2 </ b> A inserted into the lens barrel 21 from the notch 28 a described above, and the upper side is an extension portion 2 </ b> B protruding from the outer periphery of the lens barrel 21. The mounting portion 12 with the mounting hole 12a provided on one side surface corresponding to the mounting hole 27a of the flange portion 27 and the insertion portion 2A projecting just below the insertion portion 2A corresponding to the positioning recess 28b. And the projected portion 13. Similarly, on the inner side (front side) of the insertion portion 2A and the extension portion 2B, four guide pins 14 corresponding to the diaphragm blades 4A and 4B and a protruding piece for stopping the sheet metal 3 are shown as imaginary lines in FIG. 15a, 15b, a widthwise positioning projection 15c (see FIG. 8) and the like protruding from both sides are integrally provided. The insertion portion 2A is provided with a downward opening 16 in the shape of a long hole located between the guide pins 14 on both lower sides. A shaft hole 17 is formed through the extended portion 2B at a substantially upper center. On this outer side (back side), a ring-shaped protrusion 18 is provided centering on the shaft hole 17, and arm portions 7 constituting the support portion 6 are integrally protruded on both sides of the protrusion 18. . As shown in FIG. 5, both arm portions 7 have tips formed at the small-diameter shaft portion, have claw portions 7a outside the small-diameter shaft portion, and stop portions 8 at the arm-tip tips. It is attached via the part 7a. That is, the stopper portion 8 has a circular cap shape, and has a shaft hole 8a provided at the center, and a small hole corresponding to the small-diameter shaft portion and a locking hole corresponding to the claw portion 7a. From the state in which the other end 9c corresponding to the rotation shaft 9 is pivotally supported by the shaft hole 8a with respect to the tips of the both arm portions 7, the small-diameter shaft portion and the small hole, the claw portion 7a and the locking hole It is fixed by each engagement.
[0014]
As shown in FIG. 8, the rotating shaft 9 is inserted into the shaft hole 17 on the axis thereof and protrudes from the inside of the extended portion 2 </ b> B (front side) to the small diameter shaft portion 9 a on one end side, and from the inside of the protrusion 18. It has a large-diameter shaft portion 9b that protrudes outward, and a shaft portion 9c on the other end side that forms the small-diameter shaft portion at the tip. Then, one end side is pivotally supported by a small diameter shaft portion 9a fitted to the shaft hole 17, and from this state, the other end side has a small diameter at the tip of the shaft portion 9c fitted to the shaft hole 8a of the stop portion 8 described above. It is pivotally supported by the shaft. The rotation shaft 9 has an operation lever 10 connected to the large-diameter shaft portion 9b. The operation lever 10 includes a protruding wall 10a that is provided around the large-diameter shaft portion 9b and protrudes in the radial direction, and an operation portion 10b that is integrated with the upper end surface of the protruding wall 10a. The protruding wall 10a has a fan shape as shown in FIG. 7, and when it is rotated via the operation portion 10b, it hits the corresponding portion of both arm portions 7 and restricts its rotation range. Although the operation portion 10b has an arc shape and is omitted in the drawing, a plurality of knurled concave portions are formed on the outer periphery which is one step higher.
[0015]
As shown in FIGS. 6 and 8, the rotating piece 5 is in the form of an elongated piece arranged at a position one step lower on the inner side (front side) of the extension portion 2B, and is projected from both end sides so that it is a diaphragm blade. It has a pin 5a fitted to the corresponding part of 4A and 4B, and a boss part 5b protruding in the middle to form a shaft hole. And the small diameter shaft part 9a which passed the shaft hole 17 with respect to the shaft hole of the boss | hub part 5b is connected by press injection. Then, the rotating piece 5 is rotated in conjunction with the rotating shaft 9, but this rotating range is about 45 because both side portions of the rotating piece 5 come into contact with the above-described opposed surface of the extended portion 2 </ b> B. Regulated at a degree.
[0016]
As shown in FIG. 9, the aperture blades 4A and 4B have an opening 4a or an opening 4b formed in a different shape in the lower half portion overlapped with each other, and two vertical slits provided along the long piece of both sides. 4d and one vertical slit 4e provided along the short piece, and one horizontal slit 4c provided along the upper side. The opening 4a of the aperture blade 4A lacks the lower side of the arc, and the aperture 4b of the aperture blade 4B has a substantially circular shape. In the opening 4a, a filter 4f is attached to the arc portion, and in the opening 4b, a filter 4g is attached to the lower side of the arc. The two diaphragm blades 4A and 4B are in the holding frame 2 and are engaged with the vertical slits 4d and the vertical slits 4e corresponding to the guide pins 14 on both sides, so that the lower half portion is superposed vertically. And is slidable in the vertical direction (see FIG. 6). At the same time, the two diaphragm blades 4A and 4B are engaged with the horizontal slits 4c corresponding to the pins 5a on both sides of the rotating piece 5 as described above, thereby interlocking with the rotation of the rotating piece 5, that is, in different directions. When one is slid downward, the other is slid upward.
[0017]
The sheet metal 3 is a lid that closes the inner side (front side) of the holding frame 2, and includes a large opening 3a provided in the center portion as shown in FIG. 10, and an opening 3b provided in the center above the opening 3a. And openings 3c provided on both sides of the opening 3b. The opening 3 a partially overlaps the opening 16 of the holding frame 2, the opening 3 b corresponds to the center of the rotating piece 5 disposed in the holding frame 2, and the opening 3 c is the pins 5 a at both ends of the rotating shaft 5. It corresponds to. The sheet metal 3 is attached to the holding frame 2 via the projecting pieces 15a and 15b of the holding frame 2 after the rotating piece 5 and the diaphragm blades 4A and 4B are assembled in the manner described above. FIGS. 4A and 4B are views of the manual throttle device 1 that has been assembled in this way, as viewed from the front and back sides. 4A and 4B and FIG. 1B is the optical axis center of the imaging lens 20 and is located on the upper side in the opening 16 of the holding frame 2.
[0018]
In the above-described manual diaphragm device 1, as described in paragraph 0010, it is assembled to the imaging lens 20, and the open diaphragm value by the diaphragm blades 4 </ b> A and 4 </ b> B is adjusted via the operation unit 10 b of the operation lever 10. FIGS. 1A and 1B show the adjustment procedure. FIG. 1A shows the operation unit 10a rotated in the direction of the arrow X1. In this state, the diaphragm blades 4A and 4B are slid in different directions via the rotating shaft 9 and the rotating piece 5, and the optical axis center 0 is completely closed. FIG. 1B shows the operation unit 10a rotated in the direction of the arrow X2 opposite to that shown in FIG. In this state, the diaphragm blades 4A and 4B are slid in the opposite direction to FIG. 1A via the rotating shaft 9 and the rotating piece 5, and the optical axis center 0 is fully opened. In such an aperture adjustment operation, the rotation range of the operation lever 10 hits the arm portion 7 corresponding to the protruding wall 10a, and coincides with the rotation range of the rotation piece 5 described above.
[0019]
In the above-described embodiment, the support portion 6 is composed of the arm portion 7 integrally formed on the extension portion 2B and the stop portion 8 attached to the arm portion 7. The shaft hole 8a may be provided in the U-shaped intermediate piece, and the attachment portions may be provided in both of the U-shaped pieces, and the attachment portions may be attached to the corresponding portions of the extension portion 2B. Further, although the operation lever 10 is formed integrally with the rotation shaft 9, a separate product may be attached. Similarly, the rotary piece 5 can also be formed integrally with the rotary shaft 9 and the shape of the other end side of the rotary shaft 9 can be devised. As described above, the present invention only needs to include the technical elements specified in claim 1 or 3, and the details can be variously modified based on this embodiment.
[0020]
【The invention's effect】
As described above, according to the manual diaphragm device of the present invention, it is not necessary to incorporate each member for the diaphragm device in the lens barrel at the same time as the lens group in the conventional structure, so that the assembly work on the lens barrel side is simplified. At the same time, an aperture adjustment ring or the like that is integrally assembled on the outer periphery of the lens barrel is not required, and the degree of freedom in designing the lens barrel itself can be increased. Therefore, the CCTV camera imaging lens using this manual diaphragm device is easy to simplify the components of the imaging lens because the manual diaphragm device is assembled by a completely different retrofit system, and the assembly process can be improved. Cost reduction can be expected.
[Brief description of the drawings]
FIG. 1 is a diagram showing an example of a diaphragm operation of a manual diaphragm device to which the present invention is applied.
FIG. 2 is a diagram illustrating a structure example of an imaging lens using the manual diaphragm device.
FIG. 3 is a schematic diagram showing a relationship between a part of the imaging lens and a manual diaphragm device.
FIG. 4 is a diagram of the manual diaphragm device as viewed from the front and the back.
FIG. 5 is a top view of a holding frame of the manual diaphragm device.
FIG. 6 is a front view showing a holding frame of the manual throttle device.
FIG. 7 is a rear view showing a holding frame of the manual throttle device.
8 is a cross-sectional view of the holding frame of FIG. 6 in the middle up and down direction.
FIG. 9 is a view showing diaphragm blades of the manual diaphragm device.
FIG. 10 is a view showing a sheet metal of the manual throttle device.
[Explanation of symbols]
1 is a manual throttle device 2 is a holding frame 2A is an insertion part 2B is an extension part 4A, 4B is an aperture blade 5 is a rotary piece 6 is a support part 7 is an arm part 8 is a stop part 9 is a rotary shaft 10 is an operating lever 10a Is a projecting wall, 10b is an operating portion, 12 is a mounting portion, 16 is an opening, 17 is an axial hole, 20 is an imaging lens, 21 is a lens barrel, 28a is a notch, and L1 and L2 are lens groups

Claims (3)

In a manual diaphragm device that is assembled to a lens barrel and adjusts the operation of a plurality of diaphragm blades arranged in the lens barrel so as to be orthogonal to the optical axis by an operation unit arranged outside the lens barrel.
A holding frame integrally forming an insertion portion with an opening inserted from the radial direction into the lens barrel and an extension portion with a mounting portion arranged outside the lens barrel;
Two diaphragm blades as the diaphragm blades slidably disposed in the holding frame;
A shaft hole penetrating the extension portion and a support portion provided on the outer surface side corresponding to the shaft hole;
A rotating shaft that protrudes at one end side into the extended portion through the shaft hole and is pivotally supported at the other end side through the support portion;
An operation lever serving as the operation portion provided around the axis of the rotation shaft disposed on the support portion side;
A rotation piece arranged in the extension portion and connected to one end side of the rotation shaft to slide the diaphragm blades in different directions;
In the state where the holding frame, the diaphragm blade, the pivot shaft, the operation lever, and the pivot piece are assembled as a manual diaphragm device, a notch provided on the outer periphery of the lens barrel with respect to the lens barrel The insertion portion of the holding frame is inserted into the lens barrel and fixed through the attachment portion of the extension portion, and the diaphragm blade is rotated via the rotation shaft and the rotation piece by the rotation of the operation lever. The manual throttle device is characterized in that it is operated and adjusted. Said support portion, said from the outer surface of the extension component and the arm portion provided at both sides of the pivot shaft, the stop portion being connected to both arm portions are sealed pivot the other end of the pivot shaft The manual throttle device according to claim 1, comprising: An imaging lens for CCTV camera, wherein a lens barrel with a built-in lens group has a manual throttle device above Symbol claim 1.

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