JP2017122866A - Driving member, lens-barrel, and optical instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a driving member, a lens-barrel, and an optical instrument that achieve downsizing.SOLUTION: A driving member 100 according to the present invention comprises: a first actuator 103A; a first rotary shaft 102A rotated and driven by the first actuator 103A; a first moving part 111 moved by revolution of the first rotary shaft; a second actuator 103B; a second rotary shaft 102B rotated and driven by the second actuator 103B; a second moving part 111B moved by revolution of the second rotary shaft; a member to be driven L2 moved while connected to the first moving part and the second moving part; and a first guide shaft 114 and a second guide shaft 115 that guide the movement of the member to be driven L2. The first guide shaft 114, the first rotary shaft 102A, the second guide shaft 115, and the second rotary shaft 102B are located along the outer periphery of the member to be driven in this order. The distance between the center of the member to be driven L2 and the first guide shaft 114 is equal to the distance between the center and the first rotary shaft 102A, and the distance between the center and the second guide shaft 115 is equal to the distance between the center and the second rotary shaft 102B.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a driving member, a lens barrel, and an optical device.

  Conventionally, there is a lens barrel in which one lens group in a lens barrel is driven by two motors (see Patent Document 1). According to the lens barrel of this prior art, since a plurality of motors are arranged, there is a problem that the lens barrel becomes large.

JP 04-195010 A

The driving member of the present invention includes a first actuator, a first rotating shaft that is rotationally driven by the first actuator, a first moving unit that moves by rotational driving of the first rotating shaft, a second actuator, A second rotating shaft that is rotationally driven by the second actuator, a second moving portion that moves by the rotational driving of the second rotating shaft, and a first moving portion that is connected to the first moving portion and the second moving portion. Two driven members, and a first guide shaft and a second guide shaft for guiding the movement of the driven member, and in order along the outer periphery of the driven member, the first guide shaft and the first guide shaft A rotation shaft, the second guide shaft, and the second rotation shaft are disposed, and a distance between the center of the driven member and at least a part of the first guide shaft is set to the center and the first guide shaft. It is the same distance as at least a part of the rotation axis Ri, the distance between at least a portion of said center and said second guide shaft and to be the same as the distance between at least a portion configured of the center and the second rotation axis.
In the lens barrel of the present invention, the driven member is a lens holding frame that holds a lens, and includes the driving member.
In the optical apparatus of the present invention, the driven member is a lens holding frame that holds a lens, and includes the driving member.

It is sectional drawing of the lens-barrel 1 provided with the drive member 100 of 1st Embodiment. 2 is a schematic sectional view perpendicular to the direction of the optical axis OA of a lens barrel 1 including a driving member 100. FIG. FIG. 2 is an explanatory diagram of a state of a lens barrel 1 including a driving member 100 viewed from a direction 90 degrees different from FIG. 1 along the optical axis OA direction. It is a figure which shows the front-end | tip of the moving part. (A)-(d) is a figure which shows the timing of a drive of two stepping motor 103A, 103B at the time of the drive of the 2nd lens group L2.

  Hereinafter, a lens barrel 1 including a driving member according to an embodiment of the present invention will be described with reference to the drawings.

(overall structure)
FIG. 1 is a schematic cross-sectional view of the lens barrel 1 including the driving member 100 along the optical axis OA direction. FIG. 2 is a schematic sectional view perpendicular to the optical axis OA direction of the lens barrel 1 including the driving member 100. FIG. 3 is an explanatory diagram of the lens barrel 1 including the driving member 100 as viewed from a direction 90 degrees different from FIG. 1 along the optical axis OA direction.

The lens barrel 1 can be attached to and detached from the camera body 2. The lens barrel 1 includes a photographing optical system including two lens groups, a first lens group L1 and a second lens group L2. However, the lens barrel 1 is not limited to this, and may have two or more lens groups.
Light from the subject enters the camera body 2 side as subject light through the first lens group L1 and the second lens group L2.

The lens barrel 1 includes a fixed barrel 10 that is fixed to the camera body 2. The fixed cylinder 10 is a cylindrical member that is the basis of the lens barrel 1. On the camera body side of the fixed cylinder 10 in the direction of the optical axis OA, a body side fixing portion 16 is disposed.
In addition, a substrate is attached to the inside of the body side fixing unit 16, and a control unit 11 and a storage unit that control the lens barrel 1 are provided on the substrate.

  The first lens group L1 is held by the first lens holding frame 12. The first lens holding frame 12 is a substantially annular frame. The first lens holding frame 12 is fixed to the fixed cylinder 10. However, the present invention is not limited to this, and the first lens holding frame 12 may be movable in the direction of the optical axis OA.

  A diaphragm unit 13 is disposed on the rear side of the first lens unit L1. The aperture unit 13 holds aperture blades 14. The aperture blade 14 is driven to open and close by an aperture actuator 15.

(Drive member 100)
A drive member 100 is disposed on the rear side of the aperture unit 13.
The driving member 100 includes a second lens unit L2, a second lens holding frame 101 that holds the second lens unit L2, a first moving unit 111A and a second moving unit 111B, a first guide engaging unit 112A, 2 guide engaging portions 112B.
Furthermore, the driving member 100 includes a first rotating shaft 102A and a second rotating shaft 102B that engage with the first moving portion 111A and the second moving portion 111B, respectively, and the first rotating shaft 102A and the second rotating shaft 102B. A first stepping motor 103A and a second stepping motor 103B that are rotationally driven are provided.
The drive member 100 includes a first guide shaft 114 and a second guide shaft that engage with the first guide engagement portion 112A and the second guide engagement portion 112B, respectively.

  The first moving unit 111A and the second moving unit 111B, the first rotating shaft 102A and the second rotating shaft 102B, and the stepping motor 103A and the second stepping motor 103B have the same configuration. When there is no need to do this, description will be given as the moving unit 111, the rotating shaft 102, and the stepping motor 103.

The first moving unit 111A and the second moving unit 111B are members having a predetermined width extending from the outer periphery of the second lens holding frame 101 in opposite directions in the radial direction.
As shown in FIG. 1, the moving unit 111 includes a first part 111a extending outward from the end of the second lens holding frame 101 on the camera body side in the optical axis OA direction, and further outward from the first part 111a in the optical axis direction. And a second portion 111b disposed on the camera body side with respect to the first portion 111a and a connecting portion 111c for connecting the second portion 111b and the first portion 111a. Prepare.

  FIG. 4 is a diagram illustrating the tip of the moving unit 111. As shown in FIG. 4, a U-shaped groove 112 is formed at the tip of the second portion 111 b of the moving unit 111.

  As shown in FIGS. 1 and 4, a spring holding portion 120 protruding outward in the radial direction is provided on the object side in the optical axis OA direction on the outer surface of the coupling portion 111 c.

  A spring member 121 is attached to the spring holding portion 120. The spring member 121 has a U-shape, and has a central part 121a and two leg parts 121b and 121c extending radially outward from both ends of the central part 121a. The central part 121a is screwed to the spring holding part 120, the two leg parts 121b and 121c are curved as shown in FIG. 1, and a nut 130 (to be described later) is moved by the spring force to the moving part 111 side (optical axis OA). Direction camera body side). In other words, the moving part 111 is pressed against the nut 130 by the spring member 121.

  A rotating shaft 102 is inserted into the inner periphery of the U-shaped groove 112 provided at the tip of the second portion 111b of the moving part 111. The rotation shaft 102 extends in the direction of the optical axis OA, and a thread groove 104 (shown in FIG. 5 described later) is formed on the outer periphery.

  The camera body side of the rotation axis 102 in the direction of the optical axis OA is connected to the stepping motor 103 and is rotated by the rotation of the stepping motor 103.

  As shown in FIG. 1, a cover portion 105 is bridged between the base end portion on the stepping motor 103 side of the rotating shaft 102 and the front end portion on the subject side in the optical axis OA direction. A shaft insertion hole is provided at the tip of the cover portion 105, and the rotation shaft 102 is rotatably held in the shaft insertion hole.

A nut 130 is disposed between the U-shaped groove 112 of the moving part 111 and the leg parts 121 b and 121 c of the spring member 121 on the rotating shaft 102.
The nut 130 has a meshing portion 131 (shown in FIG. 5 described later) on the inner peripheral surface, and is inserted through the rotating shaft 102.
The nut 130 inserted through the rotating shaft 102 is pressed to the second portion 111b side of the moving portion 111 by the two leg portions 121b and 121c of the spring member 121 as described above.

As shown in FIG. 2, the first guide engagement portion 112 </ b> A and the second guide engagement portion 112 </ b> B are members having a predetermined width extending from the outer periphery of the second lens holding frame 101 in opposite directions in the radial direction. The first guide engaging portion 112A and the second guide engaging portion 112B, and the first moving portion 111A and the second moving portion 111B are orthogonal to each other.
As shown in FIG. 3, the first guide engagement portion 112A has a longer length in the optical axis OA direction than the second guide engagement portion 112B, and is provided with a hole 113 at the tip. A first guide shaft 114 is inserted through the hole 113.

  The first guide shaft 114 extends in the optical axis OA direction between the first lens holding frame 12 and the body-side fixing portion 16 disposed on the camera body side of the fixed tube 10 in the optical axis direction.

  At the side of the tip of the first guide engagement portion 112A, a rectangular plate-like member, the longitudinal direction extends in the direction of the optical axis OA, and the short side direction is perpendicular to the direction in which the first guide engagement portion 112A extends. A light shielding plate 116 extending in the direction is arranged.

A reference sensor 117 is arranged on the camera body side of the first guide shaft 114 in the optical axis OA direction. The reference sensor 117 is, for example, a photo interrupter.
The reference sensor 117 includes a light emitting unit 117a and a light receiving unit 117b arranged in parallel to each other. When the light shielding plate 116 passes through the gap between the light emitting unit 117a and the light receiving unit 117b, the light shielding plate 116 blocks the light emitted from the light emitting unit 117a and incident on the light receiving unit 117b, thereby generating a detection signal of the reference sensor 117. Make a change. This detection signal is transmitted to the control unit 11. The position of the second lens unit L2 can be detected by counting the number of pulses of the stepping motor 103 from the first passing through the gap.

The second guide engaging portion 112B extends from the outer peripheral side of the second lens holding frame 101 on the camera body side in the optical axis OA direction to the outer side in the radial direction opposite to the first guide engaging portion 112A. An engagement U-shaped groove 118 is provided.
The second guide shaft 115 is inserted through the guide shaft engaging U-shaped groove 118.
The second guide shaft 115 extends in the direction of the optical axis OA between the first lens holding frame 12 and the body-side fixing portion 16.

In the embodiment, on the circumference centered on the center (optical axis OA) of the second lens unit L2, at least a part of the first rotation shaft 102A, at least a part of the first guide shaft 114, and the second At least a part of the rotating shaft 102B and at least a part of the second guide shaft 115 are disposed.
Unlike the embodiment, if any one of the first rotating shaft 102A, the first guide shaft 114, the second rotating shaft 102B, or the second guide shaft 115B protrudes to the outer peripheral side, the diameter of the entire drive member 100 is increased by the amount of protrusion. Becomes larger.
However, according to the embodiment, the diameter of the entire drive member 100 can be reduced by arranging in the above order along the outer periphery and making the distance from the center substantially the same.

  Although the above-described embodiment is most preferable, the first distance between the center of the second lens unit L2 (optical axis OA) and at least a part of the first guide shaft 114 is not limited to this. The distance between the center of the second lens unit L2 (optical axis OA) and at least a part of the first rotation shaft 102A is the same, and the center of the second lens unit L2 (optical axis OA) and the second guide shaft 115 are the same. Is the same as the distance between the center of the second lens unit L2 (optical axis OA) and at least a part of the second rotating shaft 102B, and the first distance and the first distance Even if the two distances are different, the effect of miniaturization can be obtained.

Also, as shown in FIG. 2, two imaginary lines m1 and m2 that pass through the center position (optical axis OA) of the second lens holding frame 101 and are orthogonal to each other are drawn, divided into four regions, and sequentially in the circumferential direction. A first area A1, a second area A2, a third area A3, and a fourth area A4 are assumed.
In the embodiment, the first guide shaft 114 is disposed in the first region A1, the first rotation shaft 102A is disposed in the second region A2, the second guide shaft 115 is disposed in the third region A3, and the second rotation shaft. 102B is arranged in the fourth area A4.

That is, the first rotation shaft 102A is disposed in the second region A2, and the second rotation shaft 102B is disposed in the fourth region A4 that is symmetric about the second region A2 and the optical axis OA.
Therefore, since the portion for driving the second lens unit L2 is arranged at a symmetrical position shown in the upper and lower parts in the drawing without deviation, the second lens unit L2 can be driven in a balanced manner.

The first guide shaft 114 is disposed in the first region A1, and the second guide shaft 115 is disposed in a third region A3 that is symmetrical about the first region A1 and the optical axis OA.
Therefore, the portion that guides the second lens unit L2 is arranged at a symmetrical position shown on the left and right in the drawing without deviation, so that the second lens unit L2 can be driven in a balanced manner.

(Operation of the lens barrel 1)
When the stepping motor 103 (two stepping motors 103A and 103B) rotates, the rotation shaft 102 rotates. When the rotating shaft 102 rotates, the nut 130 is driven along the optical axis OA by the meshing of the screw grooves 104 and the meshing portion 131 of the nut 130.
At this time, since the second portion 111b of the moving unit 111 is biased by the nut 130 by the spring member 121, the moving unit 111, that is, the second lens unit L2 is driven in the direction of the optical axis OA.

  Here, the drive timings of the two stepping motors 103A and 103B are different. FIGS. 5A to 5D are diagrams showing driving timings of the two stepping motors 103A and 103B when the second lens unit L2 is driven.

State (a) As shown in the drawing, the front surface of the meshing part 131A of the nut 130A is in contact with the rear surface of the thread groove 104A of the first rotating shaft 102A driven by the stepping motor 103A.
The rear surface in the advancing direction of the meshing portion 131 of the nut 130B is in contact with the front surface in the advancing direction of the thread groove 104B of the second rotating shaft 102B driven by the stepping motor 103B.
Therefore, the nuts 130A and 130B, that is, the second lens group L2, are held in a state in which no play occurs between the first rotating shaft 102A and the second rotating shaft 102B.

State (b) The stepping motor 103A is driven, and the first rotating shaft 102A starts rotating.
When the stepping motor 103A is driven by a predetermined pulse, the rear surface in the traveling direction of the screw groove 104A of the first rotating shaft 102A moves forward in the traveling direction. Then, a backlash g is generated between the rear surface in the traveling direction and the front surface in the traveling direction of the meshing portion 131A of the nut 130A. Then, the front surface in the traveling direction of the thread groove 104A and the rear surface in the traveling direction of the engaging portion 131A of the nut 130A are in contact with each other.
On the other hand, since the stepping motor 103B is not driven yet, the second rotating shaft 102B has not yet rotated, and the front surface in the moving direction of the meshing portion 131B of the nut 130B is the rear surface in the moving direction of the thread groove of the second rotating shaft 102B. In other words, there is a backlash between the front and rear surfaces of the thread groove 104B and the rear surface of the engaging portion 131B of the nut 130B.

State (c) After the stepping motor 103A is driven by a predetermined pulse, the stepping motor 103B also starts to drive, and the second rotating shaft 102B also starts to rotate.
Then, the engagement portion 131A of the nut 130A and the engagement portion 131B of the nut 130B are driven in the traveling direction by being pushed by the front side in the traveling direction of the thread grooves 104A and 104B of the first rotating shaft 102A and the second rotating shaft 102B. Is done.
Accordingly, the first moving unit 111A and the second moving unit 111B, that is, the second lens unit L2, are driven by the two stepping motors 103A and 103B.
That is, since the second lens unit L2 uses two stepping motors 103A and 103B, it can be driven with a large driving force, and even a heavy lens can be moved.
Note that the information on the predetermined number of pulses (pulse information) is held in the storage unit. This pulse information is transmitted to the control unit of the camera body 2 when the lens barrel 1 is attached to the camera body 2. The control unit of the camera body 2 transmits a control instruction for the stepping motor 103 based on the pulse information to the control unit 11 of the lens barrel 1.

(D) State When stopping the nut 130A and the nut 130B, first, the stepping motor 103A is stopped. Then, the first rotating shaft 102A of the stepping motor 103A is also stopped.
At this time, since the stepping motor 103B is still driven, the second rotating shaft 102B is still rotating. Accordingly, the rear surface in the traveling direction of the nut 130B is pressed by the front surface in the traveling direction of the second rotating shaft 102B, and thus the second lens unit L2 continues to advance.

  When the stepping motor 103B moves a predetermined number of pulses, the second lens unit L2 moves forward by the amount of play g, and the front surface of the nut 130A in the advancing direction comes into contact with the rear surface in the advancing direction of the thread groove of the first rotating shaft 102A. Here, the stepping motor 103B stops.

  Similarly to the state of (a), the front surface in the traveling direction of the engaging portion 131A of the nut 130A abuts on the front surface in the traveling direction of the thread groove 104A of the first rotating shaft 102A, and the rear surface in the traveling direction of the engaging portion 131B of the nut 130B is The nuts 130A and 130B, that is, the second lens unit L2, do not cause backlash between the first rotating shaft 102A and the second rotating shaft 102B because they contact the rear surface in the traveling direction of the thread groove 104A of the first rotating shaft 102A. Held in a state.

  In this embodiment, since the driving stop times of the two stepping motors 103A and 103B are different as described above, the first moving unit 111A and the second moving unit 111B are moved between the first rotating shaft 102A and the second rotating shaft 102B. Can be held without play. That is, even when the stepping motors 103A and 103B are stopped (not energized), the first moving unit 111A and the second moving unit 111B can be held without backlash.

In the present embodiment, since one lens group (second lens group L2) is driven by two stepping motors 103A and 103B, it is possible to obtain a larger driving force than when driven by one stepping motor.
Further, since the stepping motor 103 has a self-holding force, it can maintain a stable state even when the power is not turned on.

In the present embodiment, the mode in which the driving timings of the two stepping motors 103A and 103B are shifted is described, but the present invention is not limited to this. For example, depending on the operation mode, it may be determined whether or not to perform an operation of removing the backlash, or the amount of backlash to be removed (number of moving pulses) may be changed.
As an example, in the case of a mode in which the lens is constantly moved, such as wobbling, not all of the existing play but some of the play may be removed.

  As described above, various modifications and changes are possible without being limited to the embodiments described above, and these are also within the scope of the present invention.

  A1: First region, A2: Second region, A3: Third region, A4: Fourth region, m1: Virtual line, m2: Virtual line, L2: Second lens group, OA: Optical axis, 1: Lens mirror Cylinder, 2: Camera body, 10: Fixed cylinder, 11: Control unit, 100: Driving member, 101: Second lens holding frame, 102: Rotating shaft, 102A: First rotating shaft, 102B: Second rotating shaft, 103 : Stepping motor, 103A: First stepping motor, 103B: Second stepping motor, 104: Screw groove, 104A: Screw groove, 104B: Screw groove, 111: Moving part, 111A: First moving part, 111B: Second moving 111a: first part 111b: second part 111c: connecting part 112: U-shaped groove 112A: first guide engaging part 112B: second guide engaging part 113: hole 114: first 1 guide shaft, 115: No. Guide shaft, 115B: second guide shaft, 116: light shielding plate, 118: U-shaped groove, 120: spring holding portion, 121: spring member, 130: nut, 130A: nut, 130B: nut, 131: engagement portion, 131A : Meshing part, 131B: meshing part

Claims (9)

A first actuator;
A first rotation shaft that is rotationally driven by the first actuator;
A first moving unit that moves by rotational driving of the first rotating shaft;
A second actuator;
A second rotating shaft that is rotationally driven by the second actuator;
A second moving unit that moves by rotational driving of the second rotating shaft;
One driven member that is connected to the first moving unit and the second moving unit to move;
A first guide shaft and a second guide shaft for guiding the movement of the driven member;
With
The first guide shaft, the first rotation shaft, the second guide shaft, and the second rotation shaft are arranged in order along the outer periphery of the driven member,
A distance between the center of the driven member and at least a part of the first guide shaft is the same as a distance between the center and at least a part of the first rotation shaft;
A drive member in which a distance between the center and at least a part of the second guide shaft is the same as a distance between the center and at least a part of the second rotation shaft. The drive member according to claim 1,
The driven member is substantially circular;
On a circumference around the center position of the driven member, at least a part of the first rotation shaft, at least a part of the first guide shaft, at least a part of the second rotation shaft, A drive member in which at least a part of the second guide shaft is disposed. The drive member according to claim 1 or 2,
The driven member is substantially circular;
When divided into four regions by two virtual lines that pass through the center position of the driven member and are orthogonal to each other, the first region, the second region, the third region, and the fourth region are sequentially positioned in the circumferential direction. ,
The first guide shaft is disposed in the first region, the first rotation shaft is disposed in the second region, the second guide shaft is disposed in the third region, and the second rotation shaft is disposed in the first region. Driving member arranged in four regions. It is a drive member given in any 1 paragraph of Claims 1-3,
A fixed cylinder to which the first actuator and the second actuator are fixed;
The driven member is substantially circular;
A central axis of the fixed cylinder is a driving member that passes through a central position of the driven member. It is a drive member given in any 1 paragraph of Claims 1-4,
A screw groove is formed on the outer peripheral surface of the first rotating shaft,
The first moving portion has a meshing portion that meshes with the screw groove on an inner peripheral surface, and has a shaft engaging portion through which the first rotating shaft is inserted,
A drive member having a spring portion that presses the shaft engaging portion against the first moving portion. It is a drive member given in any 1 paragraph of Claims 1-5,
A controller for controlling the first actuator and the second actuator;
The control unit is configured to change the rotation stop time of the first rotating shaft and the second rotating shaft;
A drive member characterized by the above. It is a drive member given in any 1 paragraph of Claims 1-6,
When the first moving unit and the second moving unit are moved in the same direction, the rotation direction of the first rotation shaft is different from the rotation direction of the second rotation shaft.
A drive member characterized by the above. The driven member is a lens holding frame for holding a lens;
Comprising the driving member according to any one of claims 1 to 7,
A lens barrel characterized by The driven member is a lens holding frame for holding a lens;
Comprising the driving member according to any one of claims 1 to 7,
Optical equipment characterized by.

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