JP2019032418A - Diaphragm blade driving unit, imaging apparatus including the same, moving body, and robot - Google Patents

Abstract

To suppress the rotation of a diaphragm ring caused by a vibration, an impact, or the like.SOLUTION: A diaphragm blade driving unit 100 includes a base plate 10 which has an opening 12, a diaphragm blade 20 which changes the opening area of the opening 12, and a diaphragm ring 30 which surrounds the opening 12 and is rotated to drive the diaphragm blade 20. In a plan view, the rotation axis J of the diaphragm ring 30 is coincident with the position of the center of gravity M.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a diaphragm blade drive unit, an imaging device including the diaphragm blade drive unit, a moving body, and a robot.

  An imaging device mounted on a moving body such as a vehicle or a drone includes an aperture device. The diaphragm device adjusts the amount of light that passes through the imaging lens and enters the imaging element.

  For example, Patent Document 1 includes a substrate having an opening, a diaphragm blade supported so as to be able to open and close the opening, a drive ring for opening and closing the diaphragm blade, and an actuator for rotating the drive ring. An apparatus is disclosed. A drive ring has a tooth | gear part mesh | engaged with the gearwheel rotated by an actuator in an outer periphery. In the diaphragm device of Patent Document 1, the drive ring is rotated by an actuator, and the aperture area of the diaphragm hole formed by the diaphragm blades changes. The amount of light incident on the image sensor is adjusted by the aperture area of the aperture.

Japanese Patent Laid-Open No. 2006-99395

  An imaging device mounted on a moving body receives various vibrations and impacts. For example, an imaging device mounted on a drone receives vibration from a drone flying motor. In addition, the imaging device mounted on the vehicle is subjected to vibration and impact during traveling of the vehicle. In the diaphragm device of Patent Document 1, the drive ring may rotate due to vibration, impact, or the like, and the amount of light incident on the image sensor may deviate from the set value.

  The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide an aperture blade drive unit that can suppress rotation of the aperture ring due to vibration, impact, and the like, an imaging device including the same, a moving body, and a robot. And

(1) In order to achieve the above object, the diaphragm blade drive unit according to the first aspect of the present invention is:
A main plate having an opening;
A diaphragm blade that changes the opening area of the opening,
A diaphragm ring that surrounds the opening and rotates to drive the diaphragm blade;
When viewed in plan, the rotation axis of the aperture ring and the position of the center of gravity coincide.

(2) The above diaphragm blade drive unit is
An actuator,
A gear that is rotated by the actuator,
The aperture ring may have a gear portion that meshes with the gear on the outer periphery.
(3) The aperture ring may have a protruding portion whose rotational position is detected.

  With the configurations (1) to (3) described above, the rotation axis of the aperture ring and the position of the center of gravity coincide with each other when viewed in plan, so that rotation of the aperture ring due to vibration, impact, or the like can be suppressed.

(4) The gear portion and the protruding portion may be provided symmetrically with respect to the rotation shaft.
With this configuration, the strength of the aperture ring can be increased.

(5) The aperture ring may have a through hole.
(6) The aperture ring may have a through hole between the gear portion and a portion of the inner periphery of the aperture ring facing the gear portion.
(7) The aperture ring may have a notch.
With these configurations, the rotation axis of the aperture ring and the position of the center of gravity can be easily matched.

  (8) An imaging device according to a second aspect of the present invention includes the diaphragm blade drive unit.

(9) A mobile body according to a third aspect of the present invention includes the imaging device.
(10) A robot according to a fourth aspect of the present invention includes the imaging device.

  According to the present invention, since the rotation axis of the aperture ring coincides with the position of the center of gravity, rotation of the aperture ring due to vibration, impact, or the like can be suppressed.

It is a schematic diagram which shows the imaging device provided with the aperture blade drive unit which concerns on Embodiment 1 of this invention. It is a front view which shows the aperture blade drive unit of the state which maximized the opening area based on Embodiment 1 of this invention. It is a disassembled perspective view which shows the aperture blade drive unit which concerns on Embodiment 1 of this invention. It is a front view which shows the ground plane which concerns on Embodiment 1 of this invention. It is a front view which shows the aperture blade which concerns on Embodiment 1 of this invention. It is a front view which shows the aperture ring which concerns on Embodiment 1 of this invention. It is a front view which shows the aperture ring which concerns on a comparative example. It is a front view which shows the aperture blade drive unit of the state which made the opening area the minimum based on Embodiment 1 of this invention. It is a front view which shows the aperture ring which concerns on Embodiment 2 of this invention. It is a front view which shows the modification of the aperture ring which concerns on this invention. It is a front view which shows the modification of the aperture ring which concerns on this invention.

(Embodiment 1)
With reference to FIGS. 1-8, the aperture blade drive unit 100 which concerns on embodiment of this invention is demonstrated.

As shown in FIG. 1, the diaphragm blade drive unit 100 according to the present embodiment includes an imaging lens 5 having an optical axis O, a shutter 2, an imaging element 3, and a control unit 4. Installed. The imaging device 5 is, for example, a digital camera, a monitoring camera, a camera mounted on a moving body such as a vehicle or a drone, or a camera mounted on a robot.
The diaphragm blade drive unit 100 adjusts the amount of light that passes through the imaging lens 1 and enters the imaging element 3. The image sensor 3 is, for example, an image sensor such as a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS). The control unit 4 controls the shutter 2, the image sensor 3, and the diaphragm blade drive unit 100.

As shown in FIG. 2, the diaphragm blade drive unit 100 includes a main plate 10, a plurality of diaphragm blades 20, a diaphragm ring 30, and a gear 45. As shown in FIG. 3, the diaphragm blade drive unit 100 further includes an actuator 40. The ground plane 10 has an opening 12. The aperture blade 20 changes the opening area of the opening 12 of the main plate 10. The aperture ring 30 rotates to drive the aperture blade 20. The actuator 40 rotates the aperture ring 30 via the gear 45.
The diaphragm blade drive unit 100 has a central axis J. The central axis J passes through the center of the opening 12 of the ground plane 10 and coincides with the optical axis O of the imaging lens 1 of the imaging device 5.
In FIG. 2, the front side is described as the subject side in the imaging device 5, and the back side is described as the imaging element 3 side in the imaging device 5.

The base plate 10 of the diaphragm blade drive unit 100 is formed in a disc shape from synthetic resin or the like. The base plate 10 mounts the aperture blade 20, aperture ring 30, gear 45, and actuator 40.
As shown in FIG. 4, the ground plane 10 has a circular opening 12 through which light transmitted through the imaging lens 1 passes at the center. In addition, a concave portion 14 surrounding the opening 12 is formed on the subject-side surface of the base plate 10. Further, seven support pins 16 are erected on the outer side of the recess 14 at equal intervals along the circumferential direction of the opening 12.
An aperture ring 30 is rotatably disposed in the recess 14. The support pin 16 rotatably supports the aperture blade 20. The central axis J of the diaphragm blade drive unit 100 passes through the circular center of the opening 12.

  The diaphragm blade 20 of the diaphragm blade drive unit 100 changes the opening area of the opening 12 of the main plate 10. In the present embodiment, the seven diaphragm blades 20 cooperate to change the opening area of the opening 12.

The aperture blade 20 is made of synthetic resin or the like. The aperture blade 20 has a support hole 22 and a guide hole 24 as shown in FIG. The support hole 22 is inserted into the support pin 16 of the main plate 10. The guide hole 24 is inserted into a drive pin 32 of a diaphragm ring 30 described later.
The aperture blade 20 is rotatably attached to the support pin 16 of the main plate 10.

  The aperture ring 30 of the aperture blade drive unit 100 is formed in an annular shape from synthetic resin or the like. The aperture ring 30 is integrally formed using a mold, for example. The aperture ring 30 is rotatably disposed in the recess 14 of the main plate 10 and surrounds the opening 12 of the main plate 10. The aperture ring 30 rotates about the central axis J as a rotation axis, and drives the aperture blade 20 of the aperture blade drive unit 100.

Further, when the diaphragm blade drive unit 100 is viewed in plan, the center axis J, which is the rotation axis of the diaphragm ring 30, and the position of the center of gravity M of the diaphragm ring 30 coincide. In other words, the center of gravity M of the aperture ring 30 is located on the central axis J that is the rotation axis of the aperture ring 30. Hereinafter, for easy understanding, the rotation axis of the aperture ring 30 is referred to as a rotation axis J.
As shown in FIG. 6, the aperture ring 30 includes a convex portion 31, seven drive pins 32, a gear portion 34, a protruding portion 35, and through holes 36 and 37.

  The convex portions 31 of the aperture ring 30 have a circular hole shape, and are provided on the surface of the aperture ring 30 on the image sensor 3 side at equal intervals along the circumferential direction. The convex portion 31 slides with an annular convex portion provided in the concave portion 14 of the main plate 10 when the aperture ring 30 rotates. Thereby, the load concerning the aperture ring 30 can be reduced.

  The drive pins 32 of the aperture ring 30 are T-shaped pins, and are provided on the subject side surface of the aperture ring 30 at equal intervals along the circumferential direction. Each of the drive pins 32 is inserted into each of the guide holes 24 of the aperture blade 20. The drive pin 32 moves in the guide hole 24 while pressing the inner surface of the guide hole 24 as the aperture ring 30 rotates. Thereby, the aperture blade 20 rotates around the support pin 16 of the main plate 10.

  The gear portion 34 of the aperture ring 30 is provided on a part of the outer periphery of the aperture ring 30. The gear portion 34 meshes with a gear 45 rotated by the actuator 40. Thereby, the aperture ring 30 rotates using the actuator 40 as a drive source.

  The protrusion 35 of the aperture ring 30 is provided on the outer periphery of the aperture ring 30. The protruding portion 35 is inserted through a through-hole (not shown) of the ground plane 10 and protrudes toward the imaging element 3 side of the ground plane 10. The protrusion 35 has a rotational position detected by an optical sensor (for example, a photo interrupter) (not shown) of the imaging device 5. The control unit 4 can obtain the rotation position of the aperture ring 30, the opening area of the opening 12, and the like from the rotation position of the protrusion 35 detected by the optical sensor.

The through holes 36 and 37 of the aperture ring 30 are provided for adjusting the position of the center of gravity M of the aperture ring 30. When the diaphragm blade drive unit 100 is viewed in plan, the position of the center of gravity M of the diaphragm ring 30 coincides with the rotation axis J of the diaphragm ring 30 through the through holes 36 and 37. In the present embodiment, the through hole 37 is larger than the through hole 36.
In the present embodiment, the aperture ring 30 has a gear portion 34 and a protruding portion 35 on the outer periphery. The gear portion 34 is larger than the protruding portion 35. Therefore, by providing a larger through-hole 37 in the vicinity of the gear portion 34 and providing the through-hole 36 at a position closer to the protruding portion 35 than the through-hole 37, when the aperture blade drive unit 100 is viewed in plan view, The rotational axis J of the ring 30 and the position of the center of gravity M of the aperture ring 30 can be matched. For example, the through hole 37 is provided between the gear portion 34 and a portion facing the gear portion 34 on the inner periphery of the aperture ring 30.
On the other hand, in the diaphragm ring 300 of the comparative example that does not have the through holes 36 and 37, the position of the center of gravity M is shifted from the rotation axis J in the direction of the gear portion 34 as shown in FIG.

When the diaphragm blade drive unit 100 is viewed in plan, the rotation axis J of the diaphragm ring 30 and the position of the center of gravity M of the diaphragm ring 30 coincide with each other, so that the occurrence of self-inertia moment of the diaphragm ring 30 due to vibration, impact, etc. is suppressed. The rotation of the aperture ring 30 due to vibration, impact, etc. can be suppressed. Thereby, the vibration resistance and impact resistance of the diaphragm blade drive unit 100 can be improved.
In the aperture rings 30 and 300, the holes 39 located on both sides of the drive pin 32 are holes that are formed to form the drive pin 32 into a T-shape when the aperture ring 30 is integrally formed.

  The actuator 40 of the aperture blade drive unit 100 is a drive source that rotates the aperture ring 30. The actuator 40 is, for example, a stepping motor, and is provided on the surface of the ground plane 10 on the image sensor 3 side. The rotation shaft of the actuator 40 is inserted through a through hole of the ground plate 10 (not shown) and protrudes to the subject side. A gear 45 is provided on the rotating shaft of the actuator 40 protruding toward the subject. The rotation of the rotation shaft of the actuator 40 is transmitted to the aperture ring 30 via the gear 45. As a result, the aperture ring 30 rotates about the rotation axis J.

  The gear 45 of the aperture blade drive unit 100 is provided on the rotation shaft of the actuator 40 protruding toward the subject side, and meshes with the gear portion 34 of the aperture ring 30.

  Next, the operation of the diaphragm blade drive unit 100 mounted on the imaging device 5 will be described with reference to FIGS. FIG. 2 shows the diaphragm blade drive unit 100 in a state where the opening area of the opening 12 is maximized. FIG. 8 shows the diaphragm blade drive unit 100 in a state where the opening area of the opening 12 is minimized.

The diaphragm blade drive unit 100 changes the opening area of the opening 12 from the maximum state shown in FIG. 2 to the minimum state shown in FIG. 8 by the operation of the operator.
For example, when the operator performs an operation of narrowing the opening area of the opening 12 in the state where the opening area of the opening 12 is maximized, the rotation axis of the actuator 40 is rotated clockwise by a control signal from the control unit 4. The gear 45 rotates clockwise. Due to the clockwise rotation of the gear 45, the aperture ring 30 having the gear portion 34 meshing with the gear 45 rotates about the rotation axis J counterclockwise. As a result, each of the diaphragm blades 20 is pressed clockwise on the inner surface of the respective guide hole 24 by each of the drive pins 32 of the diaphragm ring 30 and rotates clockwise around the support pin 16. The diaphragm blades 20 that rotate clockwise around the support pin 16 cooperate to narrow the opening area of the opening 12. When the opening area of the predetermined opening 12 is obtained, the rotation of the rotation shaft of the actuator 40 is stopped by the control signal from the control unit 4.

On the other hand, when the operator performs an operation to increase the opening area of the opening 12, the rotation shaft of the actuator 40 rotates counterclockwise by the control signal from the control unit 4, and the aperture ring 30 is centered on the rotation axis J. Rotate clockwise. Thereby, each of the aperture blades 20 rotates counterclockwise around the support pin 16 and cooperates to expand the opening area of the opening 12. When the opening area of the predetermined opening 12 is obtained, the rotation of the rotation shaft of the actuator 40 is stopped by the control signal from the control unit 4.
As described above, the diaphragm blade drive unit 100 changes the opening area of the opening 12 and adjusts the amount of light that passes through the imaging lens 1 and enters the imaging element 3 to a predetermined amount. The operation of reducing the opening area of the opening 12 means an operation of reducing the aperture of the imaging apparatus 5, and the operation of increasing the opening area of the opening 12 means an operation of opening the aperture of the imaging apparatus 5.

  As described above, when the diaphragm blade driving unit 100 is viewed in plan, the rotation axis J of the diaphragm ring 30 and the position of the center of gravity M of the diaphragm ring 30 coincide with each other. The rotation of the aperture ring 30 due to can be suppressed. Further, the aperture blade drive unit 100 can realize stable rotation of the aperture ring 30 by the actuator 40. As a result, the vibration resistance and impact resistance of the diaphragm blade drive unit 100 are improved, and further stable operation of the diaphragm blade drive unit 100 can be realized.

(Embodiment 2)
In the first embodiment, the gear portion 34 and the protruding portion 35 of the aperture ring 30 are arranged at an interval of about 120 ° on the outer periphery, but the arrangement of the gear portion 34 and the protruding portion 35 is not limited to this.

  In the present embodiment, the aperture blade drive unit 100 includes an aperture ring 60 instead of the aperture ring 30. Other configurations are the same as those in the first embodiment.

  As shown in FIG. 9, the aperture ring 60 includes seven drive pins 32, a gear portion 34, a protruding portion 35, and through holes 62 and 63. The gear part 34 and the protrusion part 35 of the aperture ring 60 are provided at symmetrical positions with the rotation axis J in between. The aperture ring 60 has through holes 62 and 63 instead of the through holes 36 and 37 of the aperture ring 30. Other configurations of the aperture ring 60 are the same as those of the aperture ring 30.

The gear portion 34 of the aperture ring 60 is provided on a part of the outer periphery of the aperture ring 60 and meshes with the gear 45 in the same manner as the gear portion 34 in the first embodiment. Thereby, the aperture ring 30 rotates using the actuator 40 as a drive source. Similarly to the protrusion 35 in the first embodiment, the protrusion 35 of the aperture ring 60 is provided on the outer periphery of the aperture ring 60 and protrudes toward the image sensor 3 side of the ground plane 10.
The gear part 34 and the protrusion part 35 of the aperture ring 60 are provided at symmetrical positions with the rotation axis J in between.

  The through holes 62 and 63 are holes provided for adjusting the position of the center of gravity M of the aperture ring 60, similarly to the through holes 36 and 37 in the first embodiment. The through holes 62 and 63 are provided in the vicinity of the gear portion 34 with a straight line L connecting the gear portion 34 and the protruding portion 35 interposed therebetween. The position of the center of gravity M of the aperture ring 60 coincides with the rotation axis J of the aperture ring 60 through the through holes 62 and 63.

  Since the gear portion 34 and the protruding portion 35 provided on the outer periphery of the aperture ring 60 are positioned symmetrically with respect to the rotation axis J, the sum of the volumes of the through holes 62 and 63 is set to the through hole in the first embodiment. It can be made smaller than the sum of the volumes of 36 and 37.

  As described above, in the aperture ring 60, the sum of the volumes of the through holes 62 and 63 can be reduced. Thereby, the intensity | strength of the aperture ring 60 can be made high. Further, when the diaphragm blade driving unit 100 is viewed in a plan view, the rotational axis J of the diaphragm ring 60 and the position of the center of gravity M coincide with each other as in the diaphragm ring 30 in the first embodiment. The rotation of the aperture ring 30 due to vibration, impact, etc. can be suppressed. Further, the aperture blade drive unit 100 can realize stable rotation of the aperture ring 60 by the actuator 40.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present invention.

  The aperture rings 30 and 60 may have notches in place of the through holes 36 and 37 or the through holes 62 and 63 in order to adjust the position of the center of gravity M. For example, as shown in FIG. 10, the aperture ring 30 may have notches 72 and 73 on the outer periphery instead of the through holes 36 and 37. When the diaphragm blade drive unit 100 is viewed in plan, the position of the center of gravity M of the diaphragm ring 30 coincides with the rotation axis J due to the notches 72 and 73.

  Further, as shown in FIG. 11, the aperture ring 30 may have a notch 74 on the inner periphery instead of the through holes 36 and 37. Further, the position of the center of gravity M of the aperture rings 30 and 60 may coincide with the rotation axis J due to a recess, a protrusion, or the like provided in the aperture rings 30 and 60.

  It is preferable that there are a plurality of through holes, notches, and recesses provided for adjusting the position of the center of gravity M of the aperture rings 30 and 60. Thereby, the intensity | strength of the aperture rings 30 and 60 can be made high.

  The drive pins 32 of the aperture rings 30 and 60 are not limited to the T-shape. For example, the drive pin 32 may be rod-shaped. In this case, even if the aperture rings 30 and 60 are integrally formed, the hole 39 does not occur.

DESCRIPTION OF SYMBOLS 1 Lens 2 Shutter 3 Image pick-up element 4 Control part 5 Imaging device 10 Ground plate 12 Opening part 14 Recessed part 16 Support pin 20 Diaphragm blade 22 Support hole 24 Guide hole 30 Diaphragm ring 31 Convex part 32 Drive pin 34 Gear part 35 Protrusion part 36, 37 Through hole 39 hole 40 Actuator 45 Gear 60 Aperture ring 62, 63 Through hole 72, 73, 74 Notch 100 Aperture blade drive unit 300 Aperture ring O Optical axis J Central axis, rotation axis M Center of gravity L Straight line

Claims (10)

A main plate having an opening;
A diaphragm blade that changes the opening area of the opening,
A diaphragm ring that surrounds the opening and rotates to drive the diaphragm blade;
When viewed in plan, the rotation axis of the aperture ring and the position of the center of gravity match.
Aperture blade drive unit. An actuator,
A gear that is rotated by the actuator,
The aperture ring has a gear portion that meshes with the gear on the outer periphery,
The diaphragm blade drive unit according to claim 1. The aperture ring has a protrusion whose rotational position is detected,
The diaphragm blade drive unit according to claim 2. The gear portion and the protruding portion are provided symmetrically across the rotation shaft.
The diaphragm blade drive unit according to claim 3. The aperture ring has a through hole,
The diaphragm blade drive unit according to any one of claims 1 to 4. The aperture ring has a through hole between the gear portion and a portion of the inner periphery of the aperture ring facing the gear portion,
The diaphragm blade drive unit according to any one of claims 2 to 4. The aperture ring has a notch,
The diaphragm blade drive unit according to any one of claims 1 to 6.   An imaging apparatus comprising the diaphragm blade drive unit according to any one of claims 1 to 7.   A moving body comprising the imaging device according to claim 8.   A robot comprising the imaging device according to claim 8.

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