JP2021021799A - Aperture device, and imaging apparatus having the same - Google Patents

Abstract

To provide an aperture device capable of switching the number of aperture blades, and an imaging apparatus having the same.SOLUTION: The aperture device has a plurality of aperture blades that has a rotation center pin, an open/close drive pin, and an aperture opening formation edge, for changing the diameter of an aperture opening formed by the aperture opening forming edge of the aperture blade. The plurality of aperture blades includes: a plurality of aperture blade sets; a plurality of rotating members each formed with a cam groove for driving each set of aperture blades to open/close; and switching means to switch the rotating member to be rotated.SELECTED DRAWING: Figure 2

Description

The present invention relates to a diaphragm device and an image pickup device having the same, and particularly to a diaphragm device for forming a diaphragm aperture shape by a plurality of diaphragm blades and an image pickup device having the same.

Conventionally, a diaphragm device in which a plurality of diaphragm blades equipped with a rotating shaft are arranged on the same circumference at equal angle intervals, and the diaphragm opening shape formed by overlapping the inner edges of the diaphragm blades is changed by swinging the diaphragm blades. It has been known. In such a diaphragm device, the diaphragm blades are provided with a rotation center pin and a drive pin. The rotation center pin is supported at a fixed position, the drive pin is fitted in a cam groove formed in the cam component, and the diaphragm blade swings when the drive pin is guided by the cam groove.

By the way, the number of diaphragm blades affects the number of light beams when a strong light source is photographed, and the larger the number of blades, the larger the number of light beams generated. Further, the aperture opening shape affects the blur shape around the main subject in the captured image, and the closer the aperture shape is to a circle by increasing the number of diaphragm blades, the closer the blur shape is to a circle. Patent Document 1 discloses a diaphragm device in which the aperture shape is made closer to a circular shape in a wide range of the diaphragm drive range by using two types of blades having different aperture edge shapes.

As described above, since the number of diaphragm blades affects the captured image, when shooting one program with multiple lenses, the same number of diaphragm blades is used to express the image such as the shape of the blur and the number of light beams. It is preferable to unify the entire program.

Japanese Patent No. 582205

However, there are lenses with different numbers of diaphragm blades depending on the manufacturer and shooting application (for example, for movie shooting and broadcasting), so when shooting a program with multiple lenses, the diaphragm blades are installed in advance. It is necessary to prepare the same number of lenses.

Therefore, an object of the present invention is to provide a diaphragm device capable of switching the number of diaphragm blades and a photographing device having the diaphragm device.

In order to achieve the above object, the diaphragm device according to the present invention is
In a diaphragm device having a plurality of diaphragm blades having a rotation center pin, an opening / closing drive pin, and a diaphragm opening forming edge portion, and changing the diameter of the diaphragm opening formed by the diaphragm opening forming edge portion of the diaphragm blade, the plurality of diaphragms. The blades are characterized by having a plurality of diaphragm blade sets, a plurality of rotating members formed with cam grooves for opening and closing individual diaphragm blade sets, and a switching means for switching the rotating rotating members.

According to the present invention, it is possible to provide a diaphragm device capable of switching the number of diaphragm blades and a photographing device having the diaphragm device.

Perspective view of the diaphragm device of the first embodiment An exploded perspective view of the diaphragm device of the first embodiment. A view of the diaphragm device of the first embodiment when the six blades are driven. B view when driving 11 blades of the diaphragm device of the first embodiment Simple sectional view of the drawing device of the first embodiment Flow chart at the time of switching the number of diaphragm blades of the diaphragm device of the first embodiment Schematic diagram of the system of the lens apparatus having the diaphragm apparatus of Example 1. Front view of the diaphragm device of the second embodiment when the six blades are driven. Front view of the diaphragm device of the second embodiment when driving 12 blades. Simple sectional view of the drawing device of the second embodiment A simplified cross-sectional view showing a switching operation of the diaphragm device of the second embodiment.

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

Hereinafter, the diaphragm device according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 7.

FIG. 1 is a perspective view of the diaphragm device of the first embodiment, FIG. 2 is a perspective view of a part of the diaphragm device of the first embodiment, and FIG. 3 is FIG. 1 when the six-blade drive of the diaphragm device of the first embodiment is driven. The figure seen from the direction of the arrow A, FIG. 4 is the view seen from the arrow B of FIG. 1 when the 11-blade drive of the diaphragm device of the first embodiment is performed. FIG. 5 is a simplified cross-sectional view schematically showing the engaged state of the gears of the diaphragm device of the first embodiment, FIG. 6 is a flowchart when the number of diaphragm blades of the diaphragm device of the first embodiment is switched, and FIG. 7 is the first embodiment. It is a system schematic of the lens apparatus which has an diaphragm apparatus.

The diaphragm device 1 is built in the lens body La of the lens device L, and includes a diaphragm blade support cylinder 2, two types of diaphragm blade sets 31, 32, two types of cam members 41, 42, and two types of holding plates 51. 52, a diaphragm drive unit 6, a diaphragm detection unit 7, and a diaphragm blade switching unit 8 are configured.

The first diaphragm blade set 31 is composed of six diaphragm blades 31a, and the second diaphragm blade set is composed of 11 diaphragm blades 32a. The diaphragm blades 31a have a rotation center pin 31b protruding toward the diaphragm blade support cylinder 2 and fitting into the rotation center hole 21a formed in the diaphragm blade support cylinder 2, and a first one protruding toward the first cam member 41. A drive pin 31c that fits into the cam groove 41a formed in the cam member 41 is formed. The diaphragm blades 32a have a rotation center pin 32b that protrudes toward the diaphragm blade support cylinder 2 and fits into the rotation center hole 21a formed in the diaphragm blade support cylinder 2, and a second cam member 42 that protrudes toward the second cam member 42. A drive pin 32c that fits into the cam groove 42a formed in the cam member 42 is formed.

The throttle drive unit 6 includes a motor 6a, a motor gear 6b, and an idler gear 6c. The idler gear 6c is a gear portion 41b or a second cam member 42 formed on the outer diameter of the first cam member 41. It is engaged with the gear portion 42b formed on the outer diameter. When the motor 6a is driven, the driving force of the motor 6a is transmitted to the gear portions 41b, 42b of the first or second cam members 41, 42, so that the first or second cam members 41, 42 rotate. The diaphragm device 1 is driven.

A rotation position detector 7a and a detection gear 7b are configured in the aperture detection unit 7, and the phase of the first or second cam members 41 and 42 is detected by engaging the detection gear 7b with the idler gear 6c. ..

The diaphragm blade switching portion 8 includes a switching member 8a, a switching actuator 8b that changes the position of the switching member 8a, and a support member 8c that supports the switching actuator 8b while suppressing rotation of the switching member 8a in the actuator axial direction. ing. The support member 8c is fixed to the lens body La by a screw (not shown). The motor 6a, the rotation position detector 7a, and the switching actuator 8b are electrically connected to the control board Lb, and the aperture value of the lens device L is controlled by the CPU mounted on the board Lb.

When the diaphragm device 1 is used as a six diaphragm, the idler gear 6c engages only with the gear portion 41b of the first cam member as shown in FIG. 5A. Therefore, the first cam member 41 is rotated by the driving force of the motor 6a, and only the first diaphragm blade set 31 swings (FIG. 3).

When the diaphragm device 1 is used as an 11 diaphragm, the idler gear 6c engages only with the gear portion 42b of the second cam member 42 as shown in FIG. 5 (b). Therefore, the second cam member 42 is rotated by the driving force of the motor 6a, and only the second diaphragm blade set 32 swings (FIG. 4).

When switching the number of diaphragm blades from 6 to 11, the changeover switch Lc provided on the exterior surface of the lens device L is operated in the direction of C (S101). When the changeover switch Lc is operated, a drive command is output from the control board Lb to the motor 6a, and the motor 6a rotates the first cam member 41 to the open end of the throttle based on the phase information of the rotation position detector 7a ( S102). When the first cam member 41 is rotated to the open end of the aperture, a drive command is output from the CPU to the switching actuator 8b, and the switching member 8a is driven in the direction of arrow E (S103). The idler gear 6c is restricted by the switching member 8a, and the engagement of the first cam member 41 with the gear portion 41b is released (S104). Further, when the switching member 8a is driven in the E direction, the idler gear 6c engages only with the gear portion 42b of the second cam member 42 as shown in FIG. 5B (S105). Therefore, the second cam member 42 is rotated by the driving force of the motor 6a, and only the second diaphragm blade set 32 swings (FIG. 4).

When switching from 11 diaphragm blades to 6 diaphragm blades, the changeover switch Lc is operated in the direction of D. When the changeover switch Lc is operated, a drive command is output from the control board Lb to the motor 6a, and the motor 6a rotates the second cam member 42 to the throttle open end based on the phase information of the rotation position detector 7a. When the second cam member 42 is rotated to the open end of the aperture, a drive command is output from the CPU to the switching actuator 8b, the switching member 8a is driven in the direction of arrow F, and the gears of the idler gear 6c and the second cam member 42. The engagement with the portion 42b is released. Further, when the switching member 8a is driven in the F direction, the idler gear 6c engages only with the gear portion 41b of the first cam member 41 as shown in FIG. 5A. Therefore, the first cam member 41 is rotated by the driving force of the motor 6a, and only the first diaphragm blade set 31 swings (FIG. 3).

As shown in FIG. 5, the opening diameter Y1 suitable for the positions of the first and second diaphragm blade sets 31 and 32 due to the deviation X of the positions of the first and second diaphragm blade sets 31 and 32 in the optical axis direction. Y2 is different. (The ray U represents an effective ray at an arbitrary aperture value.) Therefore, the first and second cams have an aperture area suitable for each position of the first and second aperture blade sets. The grooves 41a and 42a are set.

As described above, according to the present embodiment, it is possible to provide a diaphragm device capable of switching the number of diaphragm blades and a photographing device having the diaphragm device. In this embodiment, the rotating member is provided with a cam groove, but the same effect can be obtained even when the diaphragm blade support cylinder is provided with a cam groove and the rotating member is provided with a rotation center hole. Further, in this embodiment, a physical switch is used as a trigger for switching the number of diaphragm blades, but the same effect can be obtained even with another switching method such as switching by control using a display provided on the lens body. Be done. Further, if individual diaphragm drive units and diaphragm detection units are provided for each of the first and second diaphragm blade sets, the diaphragm blade sets can be switched without driving the rotating member to the aperture open end after the changeover switch is operated. Is also possible. Further, although the number of diaphragm blades is set to 6 and 11, the combination of the number of diaphragm blades is not limited.

Hereinafter, the diaphragm device of the second embodiment of the present invention will be described with reference to FIGS. 8 to 11. The same reference numerals are given to the parts whose functions overlap with those of the first embodiment, and the description thereof will be omitted.

8 is a front view of the diaphragm device when driving 6 blades, FIG. 9 is a front view of the diaphragm device when driving 12 blades, FIG. 10 is a schematic view showing a switching operation of the diaphragm blades of the diaphragm device, and FIG. 11 is a diaphragm. It is a schematic diagram which shows the operation of the switching member at the time of blade switching.

The diaphragm device 102 includes a diaphragm blade support cylinder 202, two types of diaphragm blade sets 312, 222, two types of cam members 412 and 422, a diaphragm drive unit 602 (not shown), a diaphragm detection unit 7, and a diaphragm blade switching unit. 802 (not shown) is configured.

The first diaphragm blade set 312 includes six diaphragm blades 312a. The second diaphragm blade set 322 includes six diaphragm blades 322a arranged at intermediate positions of the first diaphragm blades 312a when viewed from the optical axis direction.

The first cam member 412 is formed with six drive cam grooves 412a, a gear portion 412b, six relief grooves 412c wider than the drive cam groove 412a, and a connecting protrusion 412d. The relief groove 412c has an arc portion G centered on the rotation axis of the cam member and a lift portion H which is a cam locus corresponding to the drive cam groove 412a (which has substantially the same shape as the drive cam groove 412a). There is. The second cam member 422 is formed with six cam grooves 422a having the same shape as the first drive cam groove 412a and a connecting groove 422b that engages with the connecting protrusion 412d. The connecting protrusion 412d and the connecting groove 422b are arranged at positions where the first and second cam members 412 and 422 are engaged when both are located at the open end of the throttle. Therefore, the first cam member 412 and the second cam member 422 are not connected at positions other than the open end of the aperture.

The throttle drive unit 602 includes a motor 6a, a motor gear 6b, and an idler gear 602c, and the idler gear 602c is engaged only with the gear portion 412b of the first cam member 412.

The diaphragm blade switching unit 802 includes a switching member 802a, a switching actuator 8b that changes the position of the switching member 802a, and a support member 8c that supports the switching actuator 8b while suppressing rotation of the switching member 802a in the actuator axial direction. ing. The switching member 802a is arranged so as to abut on the end surface of the second cam member 422.

When the diaphragm device 102 is used as a six diaphragm, as shown in FIG. 11A, the second cam member 422 is restricted in the direction of the arrow J by the switching member 802a, so that the first cam member 412 and the first cam member 412 The connection of the cam member 422 of 2 is released. Further, as shown in FIG. 10A, since the idler gear 602c is engaged only with the gear portion 412b of the first cam member 412, only the first diaphragm blade set swings (FIG. 8). At this time, since the second drive pin 322c is located in the arc portion G of the relief groove 412c formed in the first cam member 412, the second diaphragm blade set 322 maintains the stopped state.

When the diaphragm device is used as a 12-sheet diaphragm, the second cam member 422 is regulated in the direction of arrow K by the switching member 802a as shown in FIG. 11B. As shown in FIG. 10B, since the connecting protrusion 412d and the connecting groove 422b are engaged with each other, the first cam member 412 and the second cam member 422 are connected, so that the rotation of the first cam member 412 The second cam member 422 also rotates in conjunction with this. At this time, since the second drive pin 322c is located at the lift portion H of the escape groove 412c of the first cam member, the operation of the second diaphragm blade set 322 is hindered by the first cam member 412. Swing without. Therefore, since the first and second diaphragm blade sets 312 and 322 both swing, the diaphragm device 102 is driven as a 12 diaphragm (FIG. 9).

As described above, according to the present embodiment, the distance in the optical axis direction between the two types of diaphragm sets can be shortened as compared with the first embodiment. Therefore, even if the trajectories of the two types of cam grooves are the same, the diaphragm blades It is possible to reduce the deviation of the aperture value due to the switching of the number of sheets. Further, in the case of the same combination of the number of diaphragm blades (for example, 6 blades and 12 diaphragm blades), the number of diaphragm blades can be reduced as compared with the first embodiment.

According to each of the above embodiments, it is possible to provide a diaphragm device capable of switching the number of diaphragm blades and a photographing device having the diaphragm device.

1,2 Aperture device, 2,202 Aperture blade support cylinder,
31,312 First diaphragm blade set,
32,322 Second diaphragm blade set,
31a, 32a, 312a, 322a Rotation center pin,
31b, 32b, 312b, 322b drive pins,
41,412 1st cam member (1st rotating member),
42,422 2nd cam member (2nd rotating member),
8,802 Aperture blade switching unit (switching means)

Claims (8)

In a diaphragm device having a plurality of diaphragm blades having a rotation center pin, an opening / closing drive pin, and a diaphragm opening forming edge, and changing the diameter of the diaphragm opening formed by the diaphragm opening forming edge of the diaphragm blade.
The plurality of diaphragm blades include a plurality of diaphragm blade sets and
Multiple rotating members that open and close each diaphragm blade set,
A diaphragm device having a switching means for switching a rotating member to be rotated. The diaphragm device has a first diaphragm blade set and a second diaphragm blade set.
A first rotating member that drives the opening and closing of the first diaphragm blade set, and
A second rotating member that drives the opening and closing of the second diaphragm blade set, and
The diaphragm device according to claim 1, further comprising a switching means for switching between the rotation of the first rotating member and the rotation of the second rotating member. The diaphragm device according to claim 2, wherein each rotation center pin of the first and second diaphragm blade sets is supported by one diaphragm blade support member. The first rotating member has a first cam groove for driving the opening and closing of the first diaphragm blade set.
The second rotating member has a second cam groove for driving the opening / closing of the second diaphragm blade set and a relief groove through which the opening / closing drive pin of the first diaphragm blade set is inserted.
The throttle device according to claim 2 or 3, wherein the relief groove has an arc portion centered on the rotation center of the rotating member and a lift-shaped portion corresponding to the second cam groove. .. Any one of claims 1 to 4, wherein the switching means includes a transmission member position switching means for switching the position of the driving force transmitting member for transmitting the driving force from the driving force generating means to the rotating member. Aperture device according to the section. The diaphragm device according to any one of claims 1 to 4, wherein the switching means includes a rotating member position switching means for switching the position of any of the rotating members. The diaphragm device according to any one of claims 1 to 6, wherein the switching means includes a switching position regulating means for regulating the rotation phase in which the rotation of the rotating member can be switched. An imaging device having the diaphragm device according to any one of claims 1 to 7.