JP2009169088A - Attaching mechanism for filter device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily and reliably attach various filters to the front face of a lens device. <P>SOLUTION: An attaching mechanism for attaching a filter device 10, which is composed of the filter 11 and a frame 12 for supporting the external edge of the filter 11, to the front face of the lens device 1, includes: a screw 22 disposed on the outside of the frame 12, extending perpendicular to the plate face of the filter 11 and projecting from the rear face of the filter device 1; a support member 21 mounted on the outside of the frame 12 and supporting the screw 22 so that it is rotatable; a movable pawl 23 helically fitted on the screw 22, rotatable with the rotation of the screw 22 and movable in a perpendicular direction; a first stopper 27 for locking the movable pawl 23, turned by the screw 22, into a locking position; and a second stopper 28 for locking the movable pawl 23, turned by the screw 22, into a standby position. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a mounting mechanism for a filter device, and more particularly to a mounting mechanism for easily and reliably attaching and detaching a filter device to and from a lens device.

  Electronic devices such as an imaging device and a projector include a lens device for capturing or projecting an optical image. The lens device incorporates optical components such as a plurality of lenses, filters, and diaphragms in its lens barrel, but optical components that are not incorporated in the lens device (for example, filters for special purposes) There are cases where additional installation is required in front of

  For example, a projector used for screening a digital cinema in a movie theater has a bright light source for projection onto a long-distance screen. When such a projector is used for non-cinema applications (for example, flight simulation, automobile design projection, etc.), an image is too bright when projected at a short distance. Therefore, an ND (Neutral Density) filter for dimming is applied to the lens device of the projector. It is necessary to attach it after the fact.

  As described above, when an additional filter is additionally installed in the lens device, a dedicated fitting mechanism (see, for example, Patent Document 1) is not provided on the front surface of the lens device, or the filter is screwed into the lens barrel of the lens device. When the thread groove for wearing is not formed, the filter cannot be attached to the lens device. For this reason, in such a case, for example, a filter stand is set up on the front surface of the projector, or a filter is attached to an arm extending from the projector main body.

JP 2006-330379 A

  However, the lens device of the projector may need to be moved up and down or left and right. However, in the conventional filter mounting method described above, it is necessary to adjust the position of the filter attached to another member in accordance with the movement of the lens device when the lens device is moved, and the work is complicated. Even if the filter is directly attached to the lens device, the method of attaching the tape with a tape or string is not reliable.

  Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to easily and easily install various filters on the front surface of a lens device in which a thread groove for attaching a filter or the like is not formed. It is an object of the present invention to provide a new and improved filter device mounting mechanism that can be securely mounted.

  In order to solve the above problems, according to an aspect of the present invention, in a mounting mechanism for detachably mounting a filter device including a filter and a frame that supports an outer edge portion of the filter to the front surface of the lens device. A screw extending outside the frame in a direction perpendicular to the plate surface of the filter and projecting to the back side of the filter device; and attached to the outside of the frame, the screw A support member that rotatably supports the movable claw; and a movable claw that is screwed into the screw and that can be rotated or moved in the vertical direction as the screw is rotated; and the movable claw that is rotated by the screw. A first stopper that locks in the stop position; a second stopper that locks the movable claw rotated by the screw in the retracted position; and when the screw is rotated in the forward direction, , The stepped portion formed on the lens barrel of the lens device is latched by the movable claw by moving to the front side of the filter device while being locked at the latching position by the first stopper. When the screw is rotated in the reverse direction, the movable claw is rotated to the retracted position locked by the second stopper, thereby releasing the stepped portion of the lens device by the movable claw. A mounting mechanism for the filter device is provided. The latching position is a position where the movable claw stands up in a direction in which the stepped portion formed on the lens barrel of the lens apparatus can be latched, and the retracted position is in a direction in which the movable claw does not latch the stepped portion. It is a saved position.

  With this configuration, when the filter device is mounted on the front surface of the lens device, the movable claw is hooked from the retracted position when the screw is rotated in the forward direction with the filter device frame fitted to the front surface side of the lens device. The level difference formed on the lens barrel of the lens device by rotating to the position, locked by the first stopper, and moving to the front side of the filter device by the movable claw in the locked state. The part is hooked by the movable claw. In addition, when removing the filter device attached to the lens device, if the screw is rotated in the reverse direction, the movable claw moves in the back direction of the filter device and rotates from the latching position to the retracted position. The stepped portion of the lens device by the nail is released. Accordingly, the filter device can be easily and reliably attached to and detached from the lens device by the mounting mechanism provided in the filter device.

  The outer edge portion of the filter may be cut away at a location corresponding to the mounting position of the support member with respect to the frame. With such a configuration, a space for mounting the support member can be secured so that the filter and the support member do not overlap each other, so that the size can be reduced even if the support member is attached to the filter device.

  Furthermore, a spring that is externally attached to the screw and gives elastic force to the movable claw screwed into the screw may be provided. With this configuration, the coupling force between the movable claw and the screw can be increased by the elastic force applied from the spring, so that the rotational force of the screw is transmitted to the movable claw so that the movable claw 23 can be suitably rotated together with the screw. .

  Furthermore, you may make it provide the cyclic | annular adapter detachably fitted inside the said frame. With this configuration, by fitting an adapter corresponding to the diameter of the lens device inside the frame, the frame is fitted to the lens device via the adapter, so that the mounting mechanism is a lens device having a plurality of different outer diameters. It becomes possible to respond.

  The first stopper and the second stopper may be formed by processing the support member. With this configuration, the stopper and the support member can be integrally formed, so that the number of parts of the mounting mechanism can be reduced and the structure can be simplified.

  Moreover, you may make it a knob | pick be provided in the position which protruded in the front side rather than the said filter at the edge part of the said screw in the front side of the said filter apparatus. With this configuration, the screw integrally formed with the knob can be rotated by turning the knob manually from the front side of the filter device.

  As described above, according to the present invention, it is possible to easily and reliably attach various filters to the front surface of a lens device in which a thread groove for attaching a filter or the like is not formed.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol.

  Below, the attachment mechanism of the filter apparatus concerning the 1st Embodiment of this invention is demonstrated. In the following description, an example in which a ND filter for dimming is mounted on the front surface of a lens device having a relatively large aperture (for example, 170φ, 180φ, etc.) provided in a projector used for screening a digital cinema in a movie theater. explain. However, the lens device and the filter device of the present invention are not limited to such examples.

  First, with reference to FIG. 1, the structure of the lens apparatus 1 concerning this embodiment is demonstrated. FIG. 1 is a perspective view showing a lens device 1 to which a filter device 10 according to this embodiment is mounted.

  As shown in FIG. 1, the lens device 1 is provided so as to protrude from the front surface of a projector (not shown). The projector includes, for example, a light valve that forms an image corresponding to a video signal, illumination means that guides light emitted from the light source to the light valve, a projection lens that magnifies and projects an image on the light valve, and the like. The lens barrel 2 of the lens device 1 is a housing having a substantially cylindrical shape as a whole. Inside the lens barrel 2, for example, a lens group including a projection lens (both not shown), an optical element such as a filter, and the like. Components are arranged on the optical axis. A projector equipped with such a lens device 1 separates light emitted from a light source into three primary colors of red, green, and blue using a special mirror, and synthesizes an image formed by a light valve (such as 3LCD) dedicated to each color. Then, the image is projected from the lens device 1 onto the screen. The lens device 1 may be of a type that is fixedly installed on a device body such as a projector or an imaging device, or may be of a detachable type.

  The flange 3 is an annular portion having the maximum diameter located at the front end (front side) of the lens barrel 2 of the lens device 1 (see FIG. 8 and the like), and the filter device 10 is attached to the flange 3. The diameter of the flange 3 is, for example, about 170φ and 180φ, and the width of the flange 3 is, for example, about 20 mm to 35 mm. Further, the outer peripheral surface of the lens barrel 2 of the lens device 1 is formed with unevenness composed of a plurality of step portions. Among these, a movable claw (details will be described later) of the mounting mechanism of the filter device 10 is hooked on the step portion 4 on the forefront side of the lens device 1 (that is, the step portion on the back side of the flange 3).

  Next, the filter device 10 according to the present embodiment will be described in detail with reference to FIGS. 2 and 3 are perspective views of the filter device 10 according to the present embodiment as viewed from the front side and the back side, respectively. FIG. 4 is an exploded perspective view showing the filter device 10 and the adapter 16 according to the present embodiment.

  As shown in FIGS. 1 to 3, the filter device 10 includes a filter 11 (for example, an ND filter) that is not incorporated in the lens device 10, and is mounted on the front side of the lens device 1 (that is, the front in the optical axis direction). It is detachably mounted by tools 20A and 20B (sometimes collectively referred to as “mounting tool 20”). By attaching the filter device 10 to the lens device 1, additional functions such as a dimming function using an ND filter can be added to the lens device 1.

  The filter device 10 includes a substantially disc-shaped filter 11, an annular frame 12 that supports an outer edge portion of the filter 11, and a pair of mounting tools 20 </ b> A and 20 </ b> B attached to both sides of the frame 12.

  As shown in FIGS. 2 and 3, the filter 11 is, for example, a filter plate constituting an ND filter or the like, and is formed of a substantially disc-shaped glass plate. The diameter of the filter 11 is approximately the same as the diameter of the flange 3 at the tip of the lens device 1.

  The frame 12 is an annular support member having a diameter corresponding to the outer diameter of the flange 3 of the lens device 1. The frame 12 includes a frame cover 13 and a frame main body 14, and sandwiches the outer edge portion of the filter 11 from the front and rear in the optical axis direction. The frame cover 13 and the frame main body 14 have substantially the same outer diameter, and the outer diameter is larger than the diameter of the filter 11 and the inner diameter is smaller than the diameter of the filter 11. With the filter 11 sandwiched between the frame cover 13 and the frame main body 14, the frame cover 13 is screwed to the frame main body 14 with, for example, six screws 15. As a result, the outer edge of the filter 11 is sandwiched between the frame cover 13 and the frame body 14.

  As shown in FIG. 2, the frame cover 13 has a substantially annular shape as a whole, but a wide portion 13 a is partially formed. The wide portion 13a is formed by partially forming the inner peripheral edge of the frame cover 13 in a straight line shape, and is formed at a position corresponding to the attachment location of at least two mounting tools 20A and 20B. In the illustrated frame cover 13, the wide portions 13 a are formed symmetrically at four locations on the top, bottom, left, and right, including positions (two locations on the left and right) corresponding to the attachment locations of the brackets 21 of the mounting tools 20 </ b> A and 20 </ b> B. As a result, the filter 11 can be suitably held by the frame cover 13 even when the outer edge of the filter 11 is cut out at, for example, four locations as described later (see FIG. 7). Moreover, in order to secure the installation space of the knob | pick 26 of the screw | thread 22 mentioned later, the substantially semicircle-shaped notch 13b is formed in the location corresponding to the attachment location of mounting tool 20A, 20B in the frame cover 13, for example. Yes.

  As shown in FIGS. 3 and 4, in the filter device 10 according to the present embodiment, an adapter is attached to the inner periphery of the frame 12 so that it can be attached to the lens device 1 of various sizes (diameter of the flange 3). 16 can be detachably fitted. The adapter 16 is an annular member that is detachably fitted to the inner peripheral portion of the frame body 14 of the frame 12. The outer diameter of the adapter 16 is substantially the same as the inner diameter of the frame body 14, and the inner diameter of the adapter 16 is a diameter that can be fitted to the outside of the flange 3 of the lens device 1. On the inner peripheral surface of the adapter 16, a ring-shaped receiving portion 16 a that protrudes inward is formed.

  Further, as shown in FIG. 4, a ring-shaped receiving portion 14 a projecting inward is formed on the inner peripheral surface of the frame main body 14. Thereby, when the adapter 16 is fitted inside the frame main body 14, the adapter 16 and the receiving portion 14 a come into contact with each other, so that the adapter 16 can be stably fitted inside the frame main body 14. In this way, as shown in FIG. 3, the screw is inserted into the screw hole 14 b (see FIG. 4) formed in the end surface on the back side of the frame main body 14 with the adapter 16 fitted inside the frame main body 14. 17 is screwed. Thereby, since the adapter 16 is hooked by the head of the screw 17, it can be fixed to the frame body 14 so that the adapter 16 does not fall off.

  By using such an adapter 16, one filter device 10 can be attached to a plurality of lens devices 1 of various sizes. For example, when the frame 12 of the filter device 10 is formed in a size corresponding to the large-diameter lens device 1 (for example, 180φ), and the filter device 10 is attached to the large-diameter lens device 1 (for example, 180φ). Without using the adapter 16, the frame body 14 of the filter device 10 is directly fitted to the flange 3 at the tip of the lens device 1. At this time, the receiving portion 14 a of the frame main body 14 as shown in FIG. 4 directly contacts the flange 3 of the lens device 1.

  On the other hand, when the filter device 10 is mounted on the small-diameter lens device 1 (for example, 170φ), the adapter 16 is mounted and fixed in the frame body 14 of the filter device 10, and the frame body 14 is connected via the adapter 16. The lens device 1 is fitted to the flange 3 at the tip. At this time, the receiving portion 14 a of the frame main body 14 as shown in FIG. 4 contacts the adapter 16, and the receiving portion 16 a of the adapter 16 contacts the flange 3 of the lens device 1.

  Note that only one type of adapter 16 may be used, or two or more types of adapters 16 having different diameters may be used according to the diameter of the flange 3 of the lens device 1. By using such an adapter 16, the filter device 10 can cope with the lens devices 1 of various sizes, and versatility is enhanced.

  Next, with reference to FIGS. 1-6, the attachment mechanism of the filter apparatus 10 concerning this embodiment is demonstrated in detail. 5A and 6A are perspective views showing a state in which the movable claw 23 is laid and raised in the mounting mechanism of the filter device 10 according to the present embodiment, respectively, and FIGS. 5B and 6B are FIGS. It is the elements on larger scale of FIG. 5B.

  As shown in FIGS. 1 to 6, the mounting mechanism of the filter device 10 includes a frame 12 that is fitted to the flange 3 of the lens device 1 that holds the filter 11, and a rearward direction (the lens device 1 side) outside the frame 12. ) And the mounting tools 20A and 20B attached to project. In such a mounting mechanism, a fitting portion (corresponding to the receiving portion 14 a of the frame main body 14) formed on the back side of the frame 12 is attached to the flange 3 that is the outermost diameter portion at the distal end portion of the lens device 1. At the same time, the stepped portion 4 formed on the lens barrel 2 of the lens device 1 is hooked by the movable claw 23 of the mounting tool 20. Accordingly, the filter device 10 can be mounted on the front surface of the lens device 1 by sandwiching the flange 3 of the lens device 1 between the frame 12 and the movable claw 23.

  In the illustrated example, two mounting tools 20A and 20B are attached to the left and right sides of the frame 20, but the present invention is not limited to this example, and three or more mounting tools 20 may be attached to the frame 12. Further, in order to stably attach the filter device 10 to the lens device 1, it is preferable to arrange a plurality of attachment tools 20 at equal intervals along the outer periphery of the frame 12. Below, the structure of the mounting tool 20 is explained in full detail.

  As shown in FIGS. 5 and 6, the mounting tool 20 includes a bracket 21 attached to the outer peripheral surface of the frame 12 so as to protrude to the back side of the filter device 1, and a screw 22 rotatably supported by the bracket 21. A movable claw 23 that is screwed into the screw 22 and can be rotated or moved in the optical axis direction as the screw 22 rotates, and a retaining ring that locks the rear end of the screw 22 so as not to be detached from the bracket 21. 24, a spring 25 that is extrapolated to the screw 22 and applies an elastic force in the optical axis direction to the movable claw 23, a knob 26 provided at the tip of the screw 22 on the front side of the filter device 10, and the screw 22 The first stopper 27 that locks the movable claw 23 rotated by the locking position at the latching position, and the second stopper 28 that locks the movable claw 23 rotated by the screw 22 at the retracted position.

  The bracket 21 is an example of a support member for rotatably supporting the screw 22. The bracket 21 is attached to the outer peripheral surface of the frame 12 so as to protrude toward the back side of the filter device 10. A method of attaching the bracket 21 will be described later (see FIG. 7). The bracket 21 is formed, for example, by bending a single metal plate into a flat, substantially rectangular parallelepiped box shape. That is, the bracket 21 has a box shape including a bottom surface 21a having a maximum area and four side surfaces (a front side surface 21b, a rear side surface 21c, a right side surface 21d, and a left side surface 21e) substantially perpendicular to the bottom surface 21a.

  A part of the bottom surface 21 a of the bracket 21 constitutes the second stopper 28, and a portion obtained by cutting and bending the central portion of the bottom surface 21 b constitutes the first stopper 27. That is, in the present embodiment, the first stopper 27 and the second stopper 28 are formed by processing the bracket 21 that is a support member, and the bracket 21 and the first stopper 27 and the second stopper 28 are integrally configured. Has been. Thereby, since the number of parts of the mounting tool 20 can be reduced and the apparatus configuration can be simplified, the manufacturing cost and labor can be reduced. Of course, the first stopper or the second stopper may be formed of a member different from the support member such as the bracket 21.

  Further, an L-shaped notch 21f, for example, is formed on the right side surface 21d and the left side surface 21e of the bracket 21. Thus, the bracket 21 can be suitably attached to the frame 12 by fitting the notches 21f of the right side surface 21d and the left side surface 21e of the bracket 21 to the outer periphery of the frame 12.

  Further, through holes (not shown) for penetrating both ends of the screw 22 are formed in the front side surface 21b and the rear side surface 21c of the bracket 21. Here, a method of attaching the screw 22 to the bracket 21 will be described. First, the male screw portion of the screw 22 is inserted in the optical axis direction from the front side of the bracket 21 and penetrates in the order of the front side surface 21b and the rear side surface 21c. Next, the retaining ring 24 is fitted to the rear end portion of the screw 22 protruding to the back side of the rear side surface 21 c of the bracket 21. Since the knob 26 having a larger diameter than the male screw part is integrally formed on the distal end side of the screw 22, the knob 26 cannot be passed through the through hole of the front side surface 21 b of the bracket 21 and is locked by the front side surface 21 b. The By attaching the screw 22 to the bracket 21 in this way, the screw 22 can be disposed so as to extend in the optical axis direction outside the frame 12, and the screw 22 can be rotatably supported by the bracket 21.

  Further, as shown in FIG. 2, a notch 13 b for disposing the knob 26 of the screw 22 is formed on the outer edge of the frame cover 13 so that the screw 22 is almost in contact with the outer peripheral surface of the frame 12. The bracket 21 itself is formed as thin as possible. Thereby, even if it attaches the mounting tool 20 to the filter apparatus 10, it can suppress that the whole diameter of the filter apparatus 10 becomes large, and the filter apparatus 10 can be made into a compact structure. Therefore, even when a lens cover (not shown) that covers the lens device 1 is provided, the filter device 10 can be attached to the lens device 1 within the lens cover without being obstructed by the lens cover.

  The screw 22 has a function of rotating the movable claw 23 and moving the movable claw 23 in a direction perpendicular to the plate surface of the filter 11 (that is, in the optical axis direction of the lens device 1). As described above, the screw 23 extends outside the frame 12 in the direction perpendicular to the plate surface of the filter 11 (that is, in the optical axis direction of the lens device 1) and protrudes toward the back side of the filter device 1. The bracket 21 is rotatably supported by the bracket 21. As described above, most of the male screw portion of the screw 22 protrudes to the back side of the filter device 10, but the tip portion of the screw 22 protrudes to the front side of the filter device 10. A knob 26 for turning the screw 22 by hand is provided on the tip end side of the screw 22 so as to protrude to the front side of the filter device 10. Thereby, the user can pick the knob 26 and turn the screw 22 in the forward and reverse directions. A movable claw 23 is screwed into the male screw portion of the screw 22 and a spring 25 is externally inserted.

  The movable claw 23 has a function of hooking the step portion 4 formed on the outer peripheral surface of the lens barrel 2 of the lens device 1 when the filter device 10 is attached to the lens device 1. This movable nail | claw 23 is formed with the metal piece of a substantially rectangular parallelepiped shape, for example. As shown in FIGS. 5B and 6B, a screw hole 23 a that is screwed into the screw 22 is formed through the base of the movable claw 23. The tip of the movable claw 23 is covered with a covering material 23b made of a flexible resin. As a result, the lens barrel 2 of the lens device 1 can be prevented from being damaged when hooked by the movable claw 23.

  The movable claw 23 is screwed onto the screw 22. Accordingly, the movable claw 23 rotates about the screw 22 as the screw 22 rotates, or the movable claw 23 moves in the direction perpendicular to the plate surface of the filter 11 (optical axis direction) as the screw 22 rotates. ) Can be moved.

  The spring 25 imparts an elastic force in the optical axis direction to the movable claw 23 in order to suitably rotate the movable claw 23 according to the rotation of the screw 22, and transmits the rotational force of the screw 22 to the movable claw 23. It has a function. The spring 25 is made of an elastic member such as a coil spring, and is externally attached to the screw 22. In the illustrated example, the spring 25 is externally attached to the screw 22 between the front side surface 21 b of the flange 21 and the movable claw 23. As a result, the spring 25 is sandwiched between the front side surface 21b of the flange 21 and the movable claw 23 and is compressed, so that the spring 25 presses the movable claw 23 in the back direction of the filter device 10 (backward in the optical axis direction). Then, an elastic force is applied in the direction. As a result, the coupling force between the movable claw 23 and the screw 22 is increased, and when the screw 22 is rotated, the movable claw 23 can be stably rotated together with the screw 22. Against idling can be prevented.

  With the structure described above, the movable claw 23 rotates about the screw 22 in a plane perpendicular to the screw 22 as the screw 22 rotates. When the screw 22 is rotated in the forward direction (for example, the clockwise direction when viewed from the front of the filter device 10), the movable claw 23 is also rotated in the forward direction (right direction). On the other hand, when the screw 22 is rotated in the reverse direction (for example, the counterclockwise direction when viewed from the front surface of the filter device 10), the movable claw 23 is also rotated in the reverse direction (left direction).

  A first stopper 27 and a second stopper 28 are disposed on the rotation trajectory of the movable claw 23. As described above, the first stopper 27 is formed by raising a part of the bottom surface 21 a of the bracket 21, and the second stopper 28 is configured by a part of the bottom surface 21 a of the bracket 21. For this reason, the plate surface of the first stopper 27 and the plate surface of the second stopper 28 are perpendicular to each other. The first stopper 27 has a function of locking the movable claw 23 rotated in the forward direction by the screw 22 at the latching position, and the second stopper 28 is movable by being rotated in the reverse direction by the screw 22. It has a function of locking the claw 23 at the retracted position.

  As shown in FIG. 6, the latching position is a position where the movable claw 23 stands in a direction in which the stepped portion 4 of the lens barrel 2 of the lens device 1 can be latched. The movable claw 23 positioned at this latching position is erected from the bracket 21 toward the inside of the filter device 10. On the other hand, as shown in FIG. 5, the retracted position is a position where the movable claw 23 is retracted in a direction in which it does not come into contact with the stepped portion 4 of the lens barrel 2 of the lens device 1. The movable claw 23 positioned at the retracted position is laid down so as to be housed in the bracket 21. The first stopper 27 and the second stopper 28 are provided for restricting the rotation range of the movable claw 23 by the screw 22. Due to the presence of the first stopper 27 and the second stopper 28, the movable claw 23 is For example, it can be rotated by about 90 degrees between the latching position (FIG. 6) and the retracted position (FIG. 5).

  By restricting the rotation range of the movable claw 23 by the first stopper 27 and the second stopper 28, the movement of the movable claw 23 accompanying the rotation of the screw 22 changes from the rotation about the screw 22 to the rotation of the screw 22. It switches to the movement in the axial direction (to the optical axis direction). For example, when the screw 22 is rotated in the positive direction (right direction), the movable claw 23 cannot rotate any further if it rotates in the positive direction together with the screw 22 and contacts the first stopper 27. It will be in the state latched by the latching position by 27 (refer FIG. 6). In this state, when the screw 22 is further rotated in the forward direction, the movable claw 23 screwed to the screw 22 rotates relative to the screw 22 while remaining in the latching position. The nail | claw 23 moves to the front direction (front side) of the filter apparatus 10. FIG.

  Similarly, when the screw 22 is rotated in the reverse direction (left direction), the movable claw 23 cannot rotate any further if it rotates in the reverse direction together with the screw 22 and comes into contact with the second stopper 28. The stopper 28 is locked at the retracted position (see FIG. 5). When the screw 22 is further rotated in the reverse direction in this state, the movable claw 23 screwed into the screw 22 rotates relative to the screw 22 while remaining in the retracted position. 23 moves in the back direction (back side) of the filter device 10.

  By attaching a plurality of mounting devices 20 having the above structure to the filter device 10, the filter device 10 can be easily and reliably attached to and detached from the lens device 1. That is, in a state where the frame 12 of the filter device 10 is fitted to the front surface of the lens device 1, the movable claw 23 is rotated and positioned at the latching position, and the movable claw 23 is further moved to the front side. Accordingly, the filter device 10 can be attached to the lens device 1 by holding the flange 3 of the lens device 1 between the standing movable claw 23 and the frame 12. When the attached filter device 10 is removed, the movable claw 23 is rotated and positioned at the retracted position, and the movable claw 23 is further moved to the back side. Thereby, the latching of the stepped portion 4 of the lens device 1 by the movable claw 23 is released, and the movable claw 23 can be accommodated and retracted in the bracket 21 in a state where the movable claw 23 is laid down. Thereby, the filter apparatus 10 can be removed from the lens apparatus 1 without the movable claw 23 getting in the way.

  Next, with reference to FIG. 7, the attachment method of the mounting tool 20 with respect to the flame | frame 12 of the filter apparatus 10 concerning this embodiment is demonstrated. FIG. 7 is a perspective view showing the filter device 10 according to the present embodiment. For convenience of explanation, the filter device 10 is shown by a two-dot chain line so that the frame cover 13 is seen through, and the filter 11 is hatched.

  As shown in FIG. 7, two mounting tools 20 </ b> A and 20 </ b> B are attached to both sides of the frame 12 of the filter device 10. As described above, the frame 12 includes the frame cover 13 and the frame main body 14, and the filter 11 is sandwiched therebetween. When the mounting tool 20 is attached, the front side surface 21 b of the bracket 21 is inserted into the space between the frame cover 13 and the frame main body 14, and the front side surface 21 b is fixed to the frame main body 14 with screws 18. In this way, the front side surface 21b of the bracket 21 is fixed to the front surface of the frame main body 14, and the notch 21f of the right side surface 21d and the left side surface 21e of the bracket 21 is fitted to the outer peripheral portion of the frame main body 14, thereby mounting. The tool 20 can be stably fixed to the frame 12. Furthermore, the filter device 10 can be made into a compact structure by attaching the mounting tool 20 so as not to excessively protrude outside the frame 12.

  By the way, when mounting the mounting tool 20 in this way, it is necessary to secure a mounting space for the front side surface 21 b of the bracket 21 at the mounting position of the bracket 21 with respect to the frame 12. However, if the filter 11 is shaped like a conventional disk, the outer edge of the filter 11 and the front side surface 21b of the bracket 21 overlap each other, and a mounting space cannot be secured.

  Therefore, in this embodiment, at least a portion corresponding to the mounting position of the bracket 21 with respect to the frame 12 is cut out from the outer edge portion of the disk-shaped filter 11. Specifically, as shown in FIG. 7, the outer edge of the disk-shaped filter 11 is linearly cut at four locations on the top, bottom, left, and right to form notches 11 a, of which two on the left and right are This corresponds to the mounting position of the bracket 21 of the mounting tool 20. Thus, by forming the notch 11 a in the outer edge portion of the filter 11, it is possible to secure a mounting space for the front side surface 21 b of the bracket 21 between the frame cover 13 and the frame main body 14.

  Further, the frame cover 13 is formed with a wide portion 13 a at a position and shape corresponding to the notch 11 a of the filter 11. The frame cover 14 having the wide portion 13a can hold the outer edge portion of the cut-out filter 11 without a gap. Therefore, foreign matter such as dust can be prevented from entering the filter device 10 through the gap between the inside of the frame cover 14 and the outer edge of the filter 11.

  The configuration of the mounting mechanism of the filter device 10 according to the present embodiment has been described in detail above. Next, a method for mounting the filter device 10 to the lens device 1 using the mounting mechanism of the filter device 10 according to the present embodiment will be described with reference to FIGS. 8-10 is each process drawing of the mounting method using the mounting mechanism of the filter apparatus 10 concerning this embodiment.

  When the filter device 10 is attached to the lens device 1, first, the filter device 10 is attached from the front side of the lens device 1 with the movable claw 23 of the attachment device 20 in the retracted position, and the frame 12 of the filter device 10 is attached. The flange 3 at the tip of the lens barrel 2 of the lens device 1 is fitted therein. Thereby, the frame main body 14 of the frame 12 (or the adapter 16 fitted therein) is fitted to the flange 3 of the lens device 1 without a gap and holds the flange 3. At the time of attachment, since the movable claw 23 is positioned at the retracted position, the filter device 10 can be smoothly attached to the lens device 1 without contacting the lens barrel 2 of the lens device 1.

  FIG. 8 shows a state where the filter device 10 is attached to the lens device 1 in this manner. As shown in FIG. 8, the movable claw 23 is locked by the second stopper 28 and is in a retracted position, and is retracted in the bracket 21 and is laid down. The movable claw 23 is located on the rear end side of the screw 22, that is, on the back side of the filter device 10.

  Next, the knob 26 of the screw 22 is turned in the forward direction by hand from the front side of the filter device 10. In the following description, an example in which the forward direction is the clockwise direction and the reverse direction is the counterclockwise direction will be described, but conversely, the forward direction may be the counterclockwise direction.

  By rotating the knob 26 clockwise, the screw 22 integrated with the knob 26 rotates clockwise, and the rotational force is transmitted to the movable claw 23 screwed into the screw 22. Rotate rightward until it collides with the first stopper 27. The reason why the movable claw 23 is preferably rotated together with the screw 22 at this time is that the rotational force of the screw 22 is suitably transmitted to the movable claw 23 because the movable claw 23 is pressed in the optical axis direction by the spring 25. It is.

  As the movable claw 23 rotates, as shown in FIG. 9, the movable claw 23 stands up from the bracket 21 toward the inside of the filter device 10 and is locked by the first stopper 27 to be in the latching position. And enters the stepped portion 4 formed in the lens barrel 2 of the lens apparatus 1. The step portion 4 is a concave portion on the back side of the flange 3 which is the maximum diameter portion of the lens barrel 2 of the lens device 1.

  Next, if the knob 26 is further rotated in the right direction, the movable claw 23 is locked by the first stopper 27 and cannot be rotated further in the right direction. It moves to the front side (front side) of the filter device 10. As a result, the movable claw 23 comes into contact with the step surface 4 a of the step portion 4 of the lens device 1. The step surface 4 a corresponds to the back surface of the flange 3.

  Further, when the knob 26 is strongly turned clockwise, as shown in FIG. 10, the movable claw 23 tends to move further to the front side of the filter device 10, so that the movable claw 23 strongly strengthens the step surface 4 a of the lens device 1. Tighten and hook the step 4. As a result, the frame 12 and the movable claw 23 of the filter device 10 sandwich the flange 3 of the lens device 1 from the front and back in the optical axis direction, so that the filter device 10 can be firmly fixed to the lens device 1. As described above, the filter device 10 is mounted on the lens device 1 using the mounting mechanism according to the present embodiment.

  Thereafter, when removing the filter device 10 mounted as described above from the lens device 1, the knob 26 of the screw 22 is turned by hand from the front side of the filter device 10 in the reverse direction (left direction). By turning the knob 26 counterclockwise, the screw 22 integrated with the knob 26 rotates counterclockwise, and the movable claw 23 screwed into the screw 22 moves along the screw 22 in the back direction of the filter device 10. To move away from the step surface 4 a of the lens device 1.

  Further, when the knob 26 is continuously rotated in the left direction, the movable claw 23 is rotated together with the screw 22 in the left direction, and is rotated from the latching position to the retracted position where it collides with the second stopper 28. Due to the rotation of the movable claw 23, the movable claw 23 is positioned at the retracted position latched by the second stopper 28 and is located outside the frame 12 of the filter device 10, that is, outside the flange 3 of the lens device 1. Move to. Thereby, the latching of the step part 4 of the lens device 1 by the movable claw 28 is released. In this state, the filter device 10 can be detached from the lens device 1 without bringing the movable claw 23 into contact with the lens barrel 2 of the lens device 1 by pulling the filter device 10 to the front side (front side).

  Note that an adapter 16 (see FIG. 4) that fits in the frame 12 of the filter device 10 is also attached to the lens device 1 having a different diameter and diameter from the frame 12 of the filter device 10. The mounting mechanism can be used by exchanging it with a size corresponding to the diameter.

  Heretofore, the mounting mechanism of the filter device 10 according to the present embodiment and the method for attaching and detaching the filter device 10 to and from the lens device 1 using this mechanism have been described. According to the mounting mechanism according to the present embodiment, for example, the filter device 10 can be easily and reliably mounted on the front surface of a large lens device 1 such as a projector used in a movie theater. At this time, the filter device 10 can be mounted on the lens device 1 even if the flange 3 of the lens device 1 is not formed with a thread groove for attaching a filter.

  Further, by using such a mounting mechanism, it is not necessary to form a thread groove or the like for attaching the filter device 10 to the lens device 1 itself, so that it can be used for various lens devices 1. Further, when attaching / detaching the filter device 10 to / from the lens device 1, it is only necessary to manually turn the knob 26 of the screw 22, and no tool is required, so that the operator can perform the attaching / detaching operation easily and quickly.

  Furthermore, the filter device 10 provided with such a mounting mechanism can be compatible with lens devices 1 of various sizes having different lens diameters by using the adapter 16 or the like, and is highly versatile.

  The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious that a person having ordinary knowledge in the technical field to which the present invention pertains can come up with various changes or modifications within the scope of the technical idea described in the claims. Of course, it is understood that these also belong to the technical scope of the present invention.

  For example, in the above-described embodiment, the example of the lens device 1 installed in the projector has been described, but the present invention is not limited to such an example. The lens device may be applied to various optical devices and electronic devices such as a digital camera, a digital video camera, a commercial camcorder, an imaging device such as a surveillance camera, a projection device, and an inspection device.

  Moreover, although the example of the ND filter for dimming was given as the filter 11 of the filter apparatus 10 in the said embodiment, this invention is not limited to this example. The filter may be an arbitrary filter such as a filter that reduces only light of a predetermined wavelength, or a 3D filter.

  Further, the structure of the support member that supports the screw 22 is not limited to the example of the bracket 21 according to the above-described embodiment, and any structure that can rotatably support the screw 22 extending in the optical axis direction outside the frame 12 is possible. The design may be changed to an arbitrary structure.

It is a perspective view which shows the lens apparatus with which the filter apparatus concerning the 1st Embodiment of this invention was mounted | worn. It is the perspective view which looked at the filter apparatus concerning the embodiment from the front side. It is the perspective view which looked at the filter apparatus concerning the embodiment from the back side. It is a disassembled perspective view which shows the filter apparatus and adapter concerning the embodiment. It is a perspective view which shows the state which laid the movable nail in the mounting mechanism of the filter apparatus concerning the embodiment. It is the elements on larger scale of FIG. 5A. It is a perspective view which shows the state which raised the movable nail | claw in the mounting mechanism of the filter apparatus concerning the embodiment. It is the elements on larger scale of FIG. 6A. It is a partial see-through | perspective perspective view which shows the filter apparatus concerning the embodiment. It is a side view which shows the 1st process of the mounting method using the mounting mechanism concerning the embodiment. It is a partial expansion perspective view which shows the 1st process of the mounting method using the mounting mechanism concerning the embodiment. It is a side view which shows the 2nd process of the mounting method using the mounting mechanism concerning the embodiment. It is a partial expansion perspective view which shows the 2nd process of the mounting method using the mounting mechanism concerning the embodiment. It is a side view which shows the 3rd process of the mounting method using the mounting mechanism concerning the embodiment. It is a partial expansion perspective view which shows the 3rd process of the mounting method using the mounting mechanism concerning the embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Lens apparatus 2 Lens barrel 3 Flange 4 Level difference part 4a Level difference surface 10 Filter apparatus 11 Filter 12 Frame 13 Frame cover 14 Frame main body 14a Receiving part 16 Adapter 16a Receiving part 20 Mounting tool 21 Bracket 22 Screw 23 Moving claw 24 Retaining ring 25 Spring 26 knob 27 first stopper 28 second stopper

Claims (5)

In a mounting mechanism for detachably mounting a filter device comprising a filter and a frame supporting an outer edge portion of the filter to the front surface of the lens device:
A screw extending outside the frame in a direction perpendicular to the plate surface of the filter and protruding toward the back side of the filter device;
A support member attached to the outside of the frame and rotatably supporting the screw;
A movable claw that is screwed into the screw and is rotatable or movable in the vertical direction as the screw rotates;
A first stopper for locking the movable claw rotated by the screw at a latching position;
A second stopper for locking the movable claw rotated by the screw at a retracted position;
With
When the screw is rotated in the forward direction, the movable claw is moved to the front side of the filter device in a state where the movable claw is locked to the hooking position by the first stopper, thereby allowing the lens barrel of the lens device to move. The step portion formed on is hooked by the movable claw,
When the screw is rotated in the reverse direction, the movable claw is rotated to the retracted position locked by the second stopper, thereby releasing the stepped portion of the lens device by the movable claw. A mounting mechanism for the filter device.   2. The filter device mounting mechanism according to claim 1, wherein a portion of the outer edge portion of the filter corresponding to an attachment position of the support member with respect to the frame is cut out. 3.   2. The filter device mounting mechanism according to claim 1, further comprising a spring that is externally attached to the screw and that gives an elastic force to the movable claw screwed into the screw.   The filter mechanism mounting mechanism according to claim 1, further comprising an annular adapter that is detachably fitted inside the frame. 2. The filter device mounting mechanism according to claim 1, wherein the first stopper and the second stopper are formed by processing the support member. 3.

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