JP5952155B2 - Aperture device and lens barrel - Google Patents

Description

  The present invention relates to a diaphragm device that adjusts the amount of light that passes through a lens mounted on an imaging device or the like, and a lens barrel that includes the diaphragm device.

  Conventionally, in order to adjust the amount of light transmitted through a lens mounted on an imaging device or the like, there has been an aperture device that controls the size of the aperture diameter by simultaneously rotating a plurality of aperture blades in the same direction around the optical axis. (For example, refer to Patent Documents 1 to 4.)

Japanese Utility Model Publication No. 4-22721 JP-A-9-230426 JP 2004-157269 A JP 2009-216927 A

  Conventional diaphragm devices including a plurality of diaphragm blades, including those described in the above patent documents, generally rotate the diaphragm blades and the diaphragm blades so that they can be easily attached to the lens barrel. The member for this is incorporated in the apparatus.

  In the case of such a diaphragm device, the attachment means for attaching to the lens barrel is provided in a region where the shaft of the screw inserted through the attachment means does not interfere with the driving of the diaphragm blades. For example, it is provided in the outer region of the outer peripheral edge of the base to which the diaphragm blades are attached.

  For this reason, in the conventional diaphragm device, it is necessary to make the outer diameter of the device larger than the outer diameter of the lens because the mounting means to the lens barrel is provided in the outer region of the outer peripheral edge of the base. Invited an increase in the size of the tube.

  An object of the present invention is to provide an aperture device that has a small outer diameter and can be easily attached to a lens barrel in order to eliminate the above-described problems caused by the prior art. It is another object of the present invention to provide a lens barrel that can be mounted with the diaphragm device and has a small outer diameter.

  In order to solve the above-described problems and achieve the object, an aperture device according to the present invention includes a plurality of aperture blades, a base in which light is allowed to pass, and a base that accommodates the plurality of aperture blades, and the plurality of aperture blades. A diaphragm member that is engaged with the diaphragm blades and rotates around the opening center with respect to the base to open and close the plurality of diaphragm blades. A mounting screw hole for screwing the diaphragm device to the lens barrel is formed, and the rotating member has a diameter larger than a diameter of a head of a mounting screw used when screwing the diaphragm device to the lens barrel. A screw insertion hole having a large diameter is formed, and by rotating the rotating member to a predetermined position with respect to the base, the diaphragm blade that has covered the mounting screw hole changes the mounting screw hole. The mounting screw hole and the screw insertion hole overlap, so that the entire mounting screw hole is exposed, and the mounting screw is inserted from the screw insertion hole into the mounting screw hole. It is possible to screw together.

Furthermore, in the diaphragm device according to the present invention, in the above invention, the rotating member includes a plurality of cam grooves that respectively engage with the plurality of diaphragm blades, and the screw insertion hole is sandwiched between the adjacent cam grooves. In addition, the cam groove is formed at a position on the inner side of a region near the outermost peripheral side of the cam groove. In particular, the center of the screw insertion hole is located at a position inside the outermost peripheral side of the cam groove sandwiched between the adjacent cam grooves.

  Further, in the throttling device according to the present invention, in the above invention, when the mounting screw hole is screwed together, the head of the mounting screw is completely buried in the base.

  In addition, a lens barrel according to the present invention includes the diaphragm device according to the present invention.

  According to the diaphragm device of the present invention, the outer diameter of the lens mounted on the lens barrel is adjusted by providing the mounting screw hole for mounting the device to the lens barrel in the base that accommodates the diaphragm blades. It is possible to avoid an unnecessarily large size as compared with the above. In addition, this diaphragm device can be attached to the lens barrel by rotationally driving the diaphragm blades in a slightly narrowing direction. Thereby, there is an effect that it is possible to provide an aperture device that has a small outer diameter and can be easily attached to the lens barrel. In addition, it is possible to provide a lens barrel having a small outer diameter that can be attached with the diaphragm device.

It is a disassembled perspective view of the aperture_diaphragm | restriction apparatus concerning embodiment of this invention. It is sectional drawing of each member which comprises the aperture_diaphragm | restriction apparatus concerning embodiment of this invention. FIG. 3 is a front view showing the configuration of a base 120 as viewed from the object side. It is the front view seen from the object side which shows the state in which the several aperture blade 111 was accommodated in the base 120. FIG. FIG. 3 is a front view showing the configuration of the diaphragm device 100 as viewed from the object side. It is sectional drawing cut | disconnected along the AA line shown to FIGS. 5-1, and seeing in the arrow direction. It is an enlarged view of the B section shown in FIG. FIG. 6 is a diagram for explaining the operation of the diaphragm device 100. It is a figure for demonstrating the attachment to the lens-barrel of the aperture_diaphragm | restriction apparatus. It is the front view seen from the object side which shows the state by which the aperture device 100 was attached to the lens barrel. It is sectional drawing cut | disconnected along CC line shown to FIGS. 8-1, and seeing in the arrow direction. It is an enlarged view of the D section shown in FIG. 8-2.

  Exemplary embodiments of a diaphragm device and a lens barrel according to the present invention will be described below in detail with reference to the accompanying drawings.

  FIG. 1 is an exploded perspective view of a diaphragm device according to an embodiment of the present invention. FIG. 1 shows a state viewed from an object (not shown) side. Moreover, FIG. 2 is sectional drawing of each member which comprises the aperture_diaphragm | restriction apparatus concerning embodiment of this invention. The diaphragm device 100 is used to control the amount of light transmitted through lenses mounted on various imaging devices. The symbol O indicates the optical axis (the center of the aperture of the diaphragm device 100).

  As shown in FIG. 1, the diaphragm device 100 includes a plurality of diaphragm blades 111, a base 120, a rotating member 130, and a position regulating member 140, and the plurality of diaphragm blades 111 includes the base 120 and the rotating member. 130.

  As shown in FIG. 1, a variable aperture stop for controlling the amount of transmitted light is formed by using a plurality of diaphragm blades 111. The plurality of diaphragm blades 111 have the same shape, and a substantially bow-shaped opening forming portion 111a that forms a part of the opening on the optical axis O side is formed. As shown in FIG. 2, a blade dowel 111 b projects from the image side surface of the diaphragm blade 111. The blade dowel 111b is for attaching the diaphragm blade 111 to the base 120 so as to be rotatable. On the other hand, an open / close dowel 111c projects from the object side surface of the diaphragm blade 111 (on the side opposite to the blade dowel 111b). The open / close dowel 111 c is for engaging the diaphragm blade 111 with the rotating member 130.

  As shown in FIGS. 1 and 2, a substantially circular opening 121 through which light passes is formed at the center of the base 120. The opening 121 is formed to be equal to or slightly larger than the maximum diameter of the variable aperture stop formed by the plurality of stop blades 111. Around the opening 121, a recess 122 for accommodating a plurality of diaphragm blades 111 is formed. Furthermore, a first step portion 123 with which the outer peripheral edge of the rotating member 130 abuts and a second step portion 124 with which the outer peripheral edge of the position regulating member 140 abuts are formed around the recess 122. Further, in the recess 122, blade dowel holes 125 corresponding to the number of the diaphragm blades 111 are formed. The blade dowel holes 125 are formed at equal angular intervals around the optical axis O in the circumferential direction of the opening 121. By inserting the blade dowel 111b of the diaphragm blade 111 through the blade dowel hole 125, the diaphragm blade 111 can be opened and closed. An attachment screw hole 126 is formed in the vicinity of the first step portion 123. The attachment screw hole 126 has a shape (for example, a step shape) in which the head is completely buried in the base 120 when the attachment screw is screwed.

The rotating member 130 is a driving member for driving a plurality of diaphragm blades 111 held between the base 120 and the outer peripheral edge of the rotating member 130 can be rotated with respect to the base 120 by the first step portion 123 of the base 120. Mated. As shown in FIGS. 1 and 2, a substantially circular opening 131 through which light passes is formed at the center of the rotating member 130. The opening 131 has the same size as the opening 121 of the base 120. A plurality of inverted S-shaped cam grooves 132 are formed around the opening 131. All the cam grooves 132 have the same shape, and the same number as the number of the aperture blades 111 is formed. Each cam groove 132 is engaged with an opening / closing dowel 111 c of each aperture blade 111. A screw insertion hole 133 is formed at a position inside the most peripheral side vicinity region of the cam groove 132 sandwiched between the adjacent cam grooves 132. The center of the screw insertion hole 133 is at a position inside the outermost peripheral side of the cam groove 132. The diameter of the screw insertion hole 133 is slightly larger than the diameter of the head of the mounting screw that attaches the diaphragm device 100 to the lens barrel. The same number of screw insertion holes 133 as the attachment screw holes 126 formed in the base 120 are formed. Each screw insertion hole 133 overlaps the corresponding mounting screw hole 126 when the rotating member 130 is rotated by a predetermined angle in a predetermined direction with respect to the base 120.

  The position restricting member 140 has a ring shape that lacks a part of the circumference, and prevents the rotating member 130 fitted to the base 120 from being removed so that the optical axes O of the plurality of aperture blades 111 and the rotating member 130 can be removed. This is for regulating the position in the direction.

  Next, the assembly procedure of the diaphragm device 100 will be described. FIG. 3 is a front view showing the configuration of the base 120 as viewed from the object side. FIG. 4 is a front view seen from the object side showing a state in which a plurality of aperture blades 111 are accommodated in the base 120. FIG. 5A is a front view illustrating the configuration of the diaphragm device 100 as viewed from the object side. FIG. 5-2 is a cross-sectional view taken along the line AA shown in FIG. FIG. 5C is an enlarged view of a portion B shown in FIG.

  First, the blade dowels 111b of the diaphragm blades 111 are inserted into the blade dowel holes 125 of the base 120 shown in FIG. A plurality of diaphragm blades 111 are accommodated in the base 120 by inserting the blade dowels 111b of the diaphragm blades 111 into all the blade dowel holes 125 (FIG. 4). Next, the outer peripheral edge of the rotating member 130 is fitted to the first step portion 123 of the base 120 while the open / close dowel 111 c of the diaphragm blade 111 is engaged with the cam groove 132 of the rotating member 130, respectively. Is attached to the base 120. In this way, by rotating the rotating member 130 with respect to the base 120, the plurality of aperture blades 111 can be opened and closed. Finally, in a state where the rotating member 130 is attached to the base 120, the position restricting member 140 is attached to the second step portion 124 of the base 120. By doing in this way, the position of the plurality of aperture blades 111 and the rotation member 130 in the optical axis O direction can be regulated so that the rotation member 130 does not come off the base 120 (FIGS. 5A and 5B). -2, Fig. 5-3).

  Next, the operation of the diaphragm device 100 will be described with reference to FIGS. FIG. 6 is a diagram for explaining the operation of the diaphragm device 100. The figure shows a state viewed from the object side.

  When the rotation member 130 is rotated in the direction of the arrow A with respect to the base 120 from the time of the maximum opening shown in FIG. 5A, the opening / closing dowels 111c of the respective diaphragm blades 111 are cams of the rotation member 130. The diaphragm opening diameter 111a can be reduced by moving by being guided by the groove 132 and moving the opening forming portion 111a toward the opening center. Thereafter, when the rotating member 130 is rotated in the direction of the arrow A with respect to the base 120, the open / close dowels 111c of the diaphragm blades 111 are guided by the cam grooves 132 of the rotating member 130 and moved in the original direction, and the opening forming portion The diaphragm aperture diameter can be opened by moving 111a away from the center of the aperture. The diaphragm device 100 can be driven by a drive device that has been generally used.

  As shown in FIG. 6, when the rotating member 130 is rotated in the direction of the arrow A with respect to the base 120, the aperture blade 111 that has covered the mounting screw hole 126 moves to a position where the mounting screw hole 126 is exposed. At the same time, the mounting screw hole 126 and the screw insertion hole 133 overlap. At this time, the entire mounting screw hole 126 is exposed. In this state, by inserting the attachment screw through the screw insertion hole 133 and screwing it into the attachment screw hole 126, the diaphragm device 100 can be attached to the lens barrel.

  Next, with reference to FIG. 7, FIG. 8-1, FIG. 8-2, and FIG. 8-3, attachment of the diaphragm device 100 to the lens barrel will be described. FIG. 7 is a view for explaining attachment of the diaphragm device 100 to the lens barrel. FIG. 8A is a front view seen from the object side, showing a state in which the aperture device 100 is attached to the lens barrel. FIG. 8B is a cross-sectional view taken along the line CC shown in FIG. FIG. 8C is an enlarged view of a portion D shown in FIG.

  As shown in FIG. 7 and FIG. 8A, the diaphragm device 100 is inserted from the object side of the lens barrel 200 and applied to a diaphragm device mounting portion 201 formed on the lens barrel 200. At this time, the expansion device 100 is applied to the expansion device mounting portion 201 in the state shown in FIG. 6, that is, in a state where the mounting screw holes 126 and the screw insertion holes 133 overlap and the entire mounting screw holes 126 are exposed. . Then, the mounting screw 210 is inserted from the screw insertion hole 133, and the mounting screw 210 is screwed into the mounting screw hole 126 and the screw hole 202 formed in the aperture device mounting portion 201, so that the aperture device 100 is in the lens barrel. It is attached to 200.

  As shown in FIGS. 8-2 and 8-3, when the diaphragm device 100 is attached to the lens barrel 200, the head of the mounting screw 210 screwed into the mounting screw hole 126 is completely attached to the base 120. Buried. For this reason, after the diaphragm device 100 is attached to the lens barrel 200, the diaphragm blade 111 does not interfere with the attachment screw 210, and a smooth opening / closing drive is possible.

  In general, a plurality of aperture blades, a base that accommodates the plurality of aperture blades, and a rotating member that controls the size of the aperture opening by driving the aperture blades to open and close by rotating with respect to the base. In the aperture device provided, when a plurality of aperture blades are moved in the direction of the center of the opening, a space in which the aperture blades are not present is formed in the vicinity of the outer peripheral edge of the base.

  Therefore, as described above, in the diaphragm device 100 according to the embodiment of the present invention, the diaphragm device 100 is attached to the lens barrel 200 using the space generated when the diaphragm blade 111 is moved in the direction of diaphragm. The measures are taken. That is, in this diaphragm device 100, the outer diameter of the diaphragm device 100 is set to the lens barrel 200 by providing the mounting screw hole 126 for mounting the diaphragm device 100 to the lens barrel 200 in the base 120 in which the diaphragm blade 111 is accommodated. The size of the apparatus can be reduced in the outer diameter direction by avoiding an unnecessarily large size compared to the outer diameter of the lens mounted on the lens.

  Therefore, the present invention has a further outer diameter of the diaphragm device as compared with the prior art in which the attachment means for attaching the diaphragm device to the lens barrel is provided in the outer region of the outer peripheral edge of the base to which the diaphragm blades are attached. Miniaturization of the direction can be promoted.

  Further, as described above, the diaphragm device 100 according to the embodiment of the present invention can be attached to the lens barrel 200 by rotating the rotating member 130 in the direction in which the diaphragm blade 111 is slightly narrowed. Thus, the diaphragm device 100 has an advantage that it can be easily attached to the lens barrel 200 even after being assembled as a device.

  Furthermore, according to the diaphragm device 100 according to the embodiment of the present invention, the outer diameter direction of the lens barrel 200 used together with the diaphragm device 100 can be reduced in size.

  The shape of the diaphragm blades 111 mounted on the diaphragm device 100 and the amount of movement of the diaphragm blades 111 with respect to the rotation angle of the rotating member 130 can be arbitrarily adjusted according to the outer diameter and characteristics of the lenses used together. is there.

  As described above, the diaphragm device and the lens barrel according to the present invention are useful for various imaging devices that require miniaturization, and are particularly suitable for imaging devices that require miniaturization in the outer diameter direction of the lens. Yes.

DESCRIPTION OF SYMBOLS 100 Diaphragm device 111 Diaphragm blade 111a Opening formation part 111b Blade dowel 111c Opening / closing dowel 120 Base 121,131 Opening 122 Recess 123 First step part 124 Second step part 125 Blade dowel hole 126 Mounting screw hole 130 Rotating member 132 Cam groove 133 Screw Insertion hole 140 Position restricting member 200 Lens barrel 201 Aperture device mounting portion 202 Screw hole 210 Mounting screw O Optical axis

Claims (5)

A plurality of aperture blades;
An opening that allows light to pass through, and a base that houses the plurality of diaphragm blades;
A rotating member that engages with the plurality of aperture blades, and rotates the aperture blades around the center of the opening to open and close the aperture blades;
An aperture device comprising:
A mounting screw hole for screwing the diaphragm device to the lens barrel is formed in the base,
The rotating member is formed with a screw insertion hole having a diameter larger than the diameter of the head of the mounting screw used when the diaphragm device is screwed to the lens barrel.
By rotating the rotating member to a predetermined position with respect to the base, the aperture blade that has covered the mounting screw hole moves to a position that exposes the mounting screw hole, and the mounting screw hole and the screw insertion When the hole overlaps, the entire mounting screw hole is exposed, and the mounting screw can be inserted from the screw insertion hole and screwed into the mounting screw hole. The rotating member includes a plurality of cam grooves that engage with the plurality of diaphragm blades, respectively.
2. The aperture device according to claim 1, wherein the screw insertion hole is formed at a position inside an area near the outermost peripheral side of the cam groove sandwiched between the adjacent cam grooves. The rotating member includes a plurality of cam grooves that engage with the plurality of diaphragm blades, respectively.
2. The diaphragm device according to claim 1, wherein a center of the screw insertion hole is located at a position inside the outermost peripheral side of the cam groove, which is sandwiched between the adjacent cam grooves. The mounting screw hole, when the mounting screw is screwed, any one claims 1 to 3 in which characterized in that the head of the mounting screw has a shape that buried completely the base 2. A diaphragm device according to claim 1. A lens barrel comprising the diaphragm device according to any one of claims 1 to 4 .

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