WO2021015166A1 - 鏡胴 - Google Patents

鏡胴 Download PDF

Info

Publication number
WO2021015166A1
WO2021015166A1 PCT/JP2020/028073 JP2020028073W WO2021015166A1 WO 2021015166 A1 WO2021015166 A1 WO 2021015166A1 JP 2020028073 W JP2020028073 W JP 2020028073W WO 2021015166 A1 WO2021015166 A1 WO 2021015166A1
Authority
WO
WIPO (PCT)
Prior art keywords
cylinder
cam
roller
lens
lens barrel
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/JP2020/028073
Other languages
English (en)
French (fr)
Japanese (ja)
Inventor
岩崎　博之
川鍋　裕一
慎治 大塚
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fujifilm Corp
Original Assignee
Fujifilm Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Fujifilm Corp filed Critical Fujifilm Corp
Priority to CN202080052464.0A priority Critical patent/CN114174884B/zh
Priority to JP2021534026A priority patent/JP7108142B2/ja
Publication of WO2021015166A1 publication Critical patent/WO2021015166A1/ja
Priority to US17/564,866 priority patent/US12313901B2/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B7/00—Mountings, adjusting means, or light-tight connections, for optical elements
    • G02B7/02—Mountings, adjusting means, or light-tight connections, for optical elements for lenses
    • G02B7/04—Mountings, adjusting means, or light-tight connections, for optical elements for lenses with mechanism for focusing or varying magnification
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B7/00—Mountings, adjusting means, or light-tight connections, for optical elements
    • G02B7/02—Mountings, adjusting means, or light-tight connections, for optical elements for lenses
    • G02B7/04—Mountings, adjusting means, or light-tight connections, for optical elements for lenses with mechanism for focusing or varying magnification
    • G02B7/08—Mountings, adjusting means, or light-tight connections, for optical elements for lenses with mechanism for focusing or varying magnification adapted to co-operate with a remote control mechanism
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B7/00—Mountings, adjusting means, or light-tight connections, for optical elements
    • G02B7/02—Mountings, adjusting means, or light-tight connections, for optical elements for lenses
    • G02B7/04—Mountings, adjusting means, or light-tight connections, for optical elements for lenses with mechanism for focusing or varying magnification
    • G02B7/09—Mountings, adjusting means, or light-tight connections, for optical elements for lenses with mechanism for focusing or varying magnification adapted for automatic focusing or varying magnification
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B7/00—Mountings, adjusting means, or light-tight connections, for optical elements
    • G02B7/02—Mountings, adjusting means, or light-tight connections, for optical elements for lenses
    • G02B7/14—Mountings, adjusting means, or light-tight connections, for optical elements for lenses adapted to interchange lenses

Definitions

  • the present invention relates to a lens barrel, and particularly to a lens barrel driven to rotate.
  • Patent Document 1 describes that a thrust ring is brought into contact with the end face of a rotationally driven cam cylinder to urge the cam cylinder in the optical axis direction to reduce backlash of the cam cylinder, and stop accuracy of the cam cylinder. It is described to improve.
  • One embodiment according to the technique of the present disclosure provides a lens barrel capable of improving stopping accuracy.
  • a first cylinder having a first groove arranged along the axial direction and a second groove arranged along the circumferential direction, and a cam groove, which is fitted to the inner peripheral portion of the first cylinder.
  • the second cylinder is rotatably held, the third cylinder is housed in the second cylinder and is held so as to be movable in the axial direction, and the cam groove and the third cylinder are attached to the outer peripheral portion of the third cylinder.
  • the cam follower that fits in the 1st groove, the roller support shaft that is attached to the outer peripheral part of the 2nd cylinder through the 2nd groove, the 1st roller that is supported by the roller support shaft, and the outer peripheral part of the 1st cylinder.
  • a lens barrel provided with a first frame that is movable in the axial direction and an urging member that urges the first frame in the axial direction to press and abut the first frame against the first roller. ..
  • a second cylinder supported by a roller support shaft and fitted in a second groove to position the second cylinder in the axial direction with respect to the first cylinder and / or regulate the movable range of the second cylinder.
  • the lens barrel of (1) further equipped with two rollers.
  • the third cylinder has a third cylinder movable portion that is fitted to the outer peripheral portion of the third cylinder main body and the outer peripheral portion of the third cylinder main body and is held so as to be movable in the axial direction, and a third cylinder main body. It has an urging portion that urges the third cylinder movable portion in the axial direction, and one of the pair of cam followers is attached to the third cylinder movable portion and the other is attached to the third cylinder main body portion. , (4) lens barrel.
  • the second cylinder is any one of (1) to (5) in which the opening of the cam groove is shielded by the third cylinder in the entire range of motion of the third cylinder.
  • the opening of the cam groove is movable in the third cylinder main body and the third cylinder in the entire range of motion of the third cylinder.
  • the lens barrel of (5) which is shielded by the part.
  • the urging member is composed of a spring arranged between the first frame and the second frame.
  • the lens barrel of any one of 1) to (7).
  • the cam follower has a shaft portion attached to the outer peripheral portion of the third cylinder, and a bearing attached to the shaft portion and fitted to the cam groove and the first groove, according to (1) to (9).
  • One of the lens barrels One of the lens barrels.
  • One of the lens barrels (1) to (10) further provided with a drive unit for rotationally driving the second cylinder.
  • the third cylinder is any one of (1) to (12) that holds the lens on the inner circumference.
  • Sectional drawing which shows the overall schematic structure of the interchangeable lens of 1st Embodiment Perspective view of the rear part of the lens barrel as seen from the front side Perspective view of the rear part of the lens barrel as seen from the rear side
  • An exploded perspective view of the rear part of the lens barrel Cross-sectional view showing the structure of a cam follower Enlarged sectional view of the installation part of a pair of cam followers
  • Cross-sectional view of the interchangeable lens at the location where the positioning roller is installed Enlarged sectional view of the installation part of the positioning roller
  • Sectional drawing which shows the structure of the positioning roller and the torque applying roller Perspective view showing the schematic configuration of the drive unit with the case removed.
  • FIG. 1 is a cross-sectional view showing an overall schematic configuration of an interchangeable lens according to the first embodiment.
  • the interchangeable lens 1 of the present embodiment is a so-called single focus AF lens.
  • the AF lens is a lens capable of AF (Auto Focus).
  • the interchangeable lens 1 of the present embodiment incorporates a motor for focusing.
  • the interchangeable lens 1 of the present embodiment has a first lens group L1 and a second lens group L2 in order along the optical axis Z.
  • the first lens group L1 is a fixed lens group.
  • the second lens group L2 is a lens group that moves along the optical axis Z.
  • the second lens group L2 is a focus lens group. Focus adjustment is performed by moving the second lens group L2 along the optical axis Z.
  • the lens barrel 10 of the interchangeable lens 1 of the present embodiment is mainly composed of a fixed cylinder 12, a first lens cylinder 14, a cam cylinder 16, a second lens cylinder 18, an exterior body 20, a mount 22, and the like.
  • the fixed cylinder 12 is an element that is fixed to the camera body when the interchangeable lens 1 is attached to the camera body.
  • the fixed cylinder 12 is configured by integrating the first fixed cylinder 12A, the second fixed cylinder 12B, and the rear end cover 12C.
  • the first fixed cylinder 12A and the second fixed cylinder 12B are coaxially connected by fastening the flange portions of each other with screws (not shown).
  • the rear end cover 12C is attached to the end of the second fixing cylinder 12B by screwing it to the end of the second fixing cylinder 12B with a screw (not shown).
  • the fixed cylinder 12 is an example of the first cylinder.
  • the first lens cylinder 14 is a frame for holding the first lens group L1.
  • the first lens group L1 is positioned and held on the inner peripheral portion of the first lens cylinder 14.
  • the first lens cylinder 14 is positioned and held on the inner peripheral portion of the first fixed cylinder 12A.
  • the cam cylinder 16 is fitted to the inner peripheral portion of the second fixed cylinder 12B and is rotatably held by the inner peripheral portion of the second fixed cylinder 12B.
  • the cam cylinder 16 is an example of the second cylinder.
  • the second lens cylinder 18 is a frame for holding the second lens group L2.
  • the second lens group L2 is positioned and held on the inner peripheral portion of the second lens cylinder 18.
  • the second lens cylinder 18 is housed in the inner peripheral portion of the cam cylinder 16 and is held so as to be movable in the axial direction.
  • the second lens cylinder 18 moves back and forth along the optical axis Z by rotating the cam cylinder 16.
  • the drive mechanism and position detection mechanism of the second lens cylinder 18 will be described later.
  • the second lens cylinder 18 is an example of the third cylinder.
  • the exterior body 20 constitutes the exterior of the interchangeable lens 1.
  • the exterior body 20 is configured by combining a plurality of elements.
  • the elements constituting the exterior body 20 also include an operating member of the interchangeable lens 1 (for example, a focus ring 2 and the like).
  • the exterior body 20 is fixedly attached to the fixed cylinder 12.
  • the mount 22 is provided at the rear end of the lens barrel 10.
  • the mount 22 is composed of, for example, a bayonet mount.
  • the interchangeable lens 1 is detachably attached to the camera body via the mount 22.
  • FIG. 2 and 3 are perspective views of a rear portion of the lens barrel (a portion of the fixed cylinder 12 behind the second fixed cylinder 12B) with the exterior body removed.
  • FIG. 2 is a perspective view of the rear portion of the lens barrel as viewed from the front side.
  • FIG. 3 is a perspective view of the rear portion of the lens barrel as viewed from the rear side.
  • FIG. 4 is an exploded perspective view of the rear portion of the lens barrel.
  • the drive mechanism of the second lens cylinder 18 is composed of a so-called cam mechanism.
  • the cam mechanism includes a pair of cam followers 30A and 30B provided in the second lens cylinder 18, a pair of cam grooves 40A and 40B provided in the cam cylinder 16, a straight groove 50 provided in the second fixed cylinder 12B, and a cam cylinder. It is configured to include a positioning roller 60 provided in 16, a positioning groove 70 provided in the second fixed cylinder 12B, and a drive unit 80 for rotating the cam cylinder 16. Further, the drive mechanism of the second lens cylinder 18 includes a torque applying mechanism 100 that applies load torque to the rotation of the cam cylinder 16.
  • the pair of cam followers 30A and 30B are provided at three locations on the outer peripheral surface of the second lens cylinder 18.
  • the pair of cam followers 30A and 30B are arranged at equal intervals along the circumferential direction.
  • the pair of cam followers 30A and 30B are arranged in the front-rear direction along the optical axis Z.
  • the cam follower 30A located on the front side (subject side) is referred to as a first cam follower 30A
  • the cam follower 30B located on the rear side (image side) is referred to as a second cam follower 30B to distinguish between the two.
  • FIG. 5 is a cross-sectional view showing the configuration of the cam follower. Although the figure shows the second cam follower 30B, the first cam follower 30A has the same configuration.
  • the cam follower has a shaft portion 31 and a pair of bearings 32A and 32B mounted on the shaft portion 31.
  • the shaft portion 31 has a cylindrical shape.
  • a screw 33 is passed through the hollow portion of the shaft portion 31, and the shaft portion 31 is screwed to the outer peripheral portion of the second lens cylinder 18.
  • a screw hole 35 is provided on the outer peripheral portion of the second lens cylinder 18 at a mounting location of the shaft portion 31.
  • the pair of bearings 32A and 32B are each composed of rolling bearings such as ball bearings.
  • the pair of bearings 32A and 32B is composed of a first bearing 32A located on the tip end side of the shaft portion 31 and a second bearing 32B located on the proximal end side of the shaft portion 31.
  • a spacer 34 is arranged between the first bearing 32A and the second bearing 32B.
  • the inner ring portion of the first bearing 32A and the second bearing 32B is lightly press-fitted into the shaft portion 31 and mounted on the shaft portion 31.
  • the outer ring portion of the first bearing 32A and the second bearing 32B mounted on the shaft portion 31 is rotatably held with respect to the shaft portion 31.
  • the second lens cylinder 18 has a main body portion 18A and a movable portion 18B provided at the tip of the main body portion 18A.
  • the movable portion 18B has a cylindrical shape.
  • the main body portion 18A has a fitting portion 18a to which the movable portion 18B fits at the tip end.
  • the fitting portion 18a is composed of a step portion, and is configured by reducing the tip portion of the main body portion 18A.
  • the movable portion 18B is fitted to the outer periphery of the fitting portion 18a and attached to the main body portion 18A.
  • the main body portion 18A is an example of the third cylinder main body portion
  • the movable portion 18B is an example of the third cylinder movable portion.
  • a protrusion 24 is provided on the inner circumference of the movable portion 18B.
  • a groove portion 26 is provided on the outer periphery of the fitting portion 18a.
  • the protrusions 24 are provided at three locations on the inner peripheral surface of the movable portion 18B.
  • the groove portion 26 is composed of a groove into which the protrusion portion 24 is fitted. Grooves 26 are provided at three locations on the outer peripheral surface of the fitting portion 18a.
  • the groove portion 26 has an introduction portion 26A and a regulation portion 26B.
  • the introduction portion 26A is formed from the tip of the main body portion 18A along the optical axis Z.
  • the regulation portion 26B is formed along the circumferential direction from the end portion of the introduction portion 26A.
  • the movable portion 18B is attached to the main body portion 18A by fitting the protrusion 24 to the regulation portion 26B of the groove portion 26. As a result, the movable portion 18B is prevented from coming off and attached to the main body portion 18A.
  • the protrusion 24 is configured to fit the regulation portion 26B with a certain amount of play. That is, the width in the optical axis direction is narrower than the width in the optical axis direction of the regulating unit 26B. As a result, the movable portion 18B can be movably held along the optical axis Z in a state where the protrusion 24 is fitted to the regulation portion 26B.
  • the urging spring 18C is composed of a wave washer (corrugated washer).
  • the wave washer is made by bending a flat washer into a wavy shape, and when it is crushed, it acts as a spring to remove an axial gap.
  • the urging spring 18C is arranged between the movable portion 18B and the main body portion 18A at the rear end portion of the movable portion 18B. As a result, the movable portion 18B is urged toward the tip end direction along the optical axis Z with respect to the main body portion 18A.
  • the front first cam follower 30A which is one cam follower
  • the rear second cam follower 30B which is the other cam follower
  • the movable portion 18B is urged toward the tip end along the optical axis Z with respect to the main body portion 18A. Therefore, the first cam follower 30A and the second cam follower 30B are urged in a direction away from each other along the optical axis Z.
  • a pair of cam grooves 40A and 40B are provided at three locations on the peripheral surface of the cam cylinder 16.
  • the arrangement interval of the pair of cam grooves 40A and 40B is the same as the arrangement interval of the pair of cam followers 30A and 30B. That is, they are arranged at equal intervals along the circumferential direction.
  • the pair of cam grooves 40A and 40B have the same shape (cam locus) and are arranged in the front-rear direction along the optical axis Z. Therefore, the pair of cam grooves 40A and 40B are arranged in parallel with each other.
  • the cam groove 40A located on the front side is referred to as a first cam groove 40A
  • the cam groove 40B located on the rear side is referred to as a second cam groove 40B to distinguish between the two.
  • the pair of cam followers 30A and 30A are individually fitted into the pair of cam grooves 40A and 40B. That is, the first cam follower 30A fits into the first cam groove 40A, and the second cam follower 30B fits into the second cam groove 40B.
  • FIG. 6 is an enlarged cross-sectional view of the installation portion of the pair of cam followers.
  • the first cam follower 30A and the second cam follower 30B are urged by the urging spring 18C in a direction away from each other along the optical axis Z. Therefore, when the first cam follower 30A is fitted into the first cam groove 40A, the first cam follower 30A presses against the inner wall surface 40a on the front side of the first cam groove 40A and fits.
  • the second cam follower 30B when the second cam follower 30B is fitted into the second cam groove 40B, the second cam follower 30B presses against the inner wall surface 40b on the rear side of the second cam groove 40B and is fitted. As a result, the play generated between the cam cylinder 16 and the second lens cylinder 18 can be removed, and the second lens cylinder 18 can be stably held with respect to the cam cylinder 16.
  • the straight groove 50 is composed of linear grooves arranged along the optical axis Z.
  • the straight grooves 50 are provided at three locations on the peripheral surface of the second fixed cylinder 12B.
  • the arrangement interval of the straight groove 50 is the same as the arrangement interval of the pair of cam followers 30A and 30B. That is, they are arranged at equal intervals along the circumferential direction.
  • the pair of cam followers 30A and 30B are fitted in the same straight groove 50.
  • the straight groove 50 is an example of the first groove.
  • the positioning roller 60 is a roller that positions the cam cylinder 16 in the optical axis direction with respect to the second fixed cylinder 12B.
  • the positioning roller 60 also functions as a roller that regulates the rotation range of the cam cylinder 16.
  • the positioning rollers 60 are provided at three locations on the outer peripheral surface of the cam cylinder 16.
  • the positioning rollers 60 are arranged at equal intervals along the circumferential direction.
  • FIG. 7 is a cross-sectional view of the interchangeable lens at the location where the positioning roller is installed. Further, FIG. 8 is an enlarged cross-sectional view of the installation portion of the positioning roller. Further, FIG. 9 is a cross-sectional view showing the configurations of the positioning roller and the torque applying roller.
  • the positioning roller 60 is composed of bearings (rolling bearings such as ball bearings).
  • the inner ring portion of the positioning roller 60 is lightly press-fitted into the roller support shaft 61 provided on the cam cylinder 16 and mounted on the roller support shaft 61.
  • the outer ring portion of the positioning roller 60 mounted on the roller support shaft 61 is rotatably supported.
  • the roller support shaft 61 has a cylindrical shape.
  • a screw 62 is passed through the hollow portion of the roller support shaft 61, and the roller support shaft 61 is screwed to the outer peripheral portion of the cam cylinder 16.
  • a screw hole 64 is provided at a mounting location of the roller support shaft 61 on the outer peripheral portion of the cam cylinder 16.
  • the positioning groove 70 is composed of linear grooves arranged along the circumferential direction.
  • the positioning grooves 70 are provided at three locations on the peripheral surface of the second fixing cylinder 12B.
  • the arrangement interval of the positioning groove 70 is the same as the arrangement interval of the positioning roller 60. That is, they are arranged at equal intervals along the circumferential direction.
  • the positioning groove is an example of the second groove.
  • the positioning roller 60 fits into the positioning groove 70.
  • the cam cylinder 16 is positioned in the optical axis direction with respect to the second fixed cylinder 12B. Further, the rotation range (movable range) of the cam cylinder 16 is regulated with respect to the second fixed cylinder 12B.
  • the positioning roller 60 is an example of the second roller.
  • the drive unit 80 rotates and drives the cam cylinder 16.
  • the cam cylinder 16 has a drive gear portion 16A on the inner peripheral portion at the rear end thereof.
  • the drive unit 80 rotationally drives the gear portion 16A to rotate the cam cylinder 16.
  • the drive unit 80 is attached to the rear end cover 12C of the fixed cylinder 12.
  • the drive unit 80 includes a motor and a speed reducer, and these are assembled into a case 82 to form a unit.
  • FIG. 10 is a perspective view showing a schematic configuration of the drive unit with the case removed.
  • 11 and 12 are views showing a state in which the motor and the speed reducer are attached to the lens barrel.
  • FIG. 11 corresponds to a rear view of the lens barrel with the exterior body removed.
  • FIG. 12 corresponds to a rear perspective view of the rear portion of the lens barrel with the exterior body removed. Note that FIGS. 11 and 12 show a state in which the rear end cover 12C of the fixed cylinder 12 and the case 82 of the drive unit 80 are omitted for convenience.
  • the drive unit 80 includes a motor 84 and a speed reducer 88 that reduces the rotation of the motor 84.
  • the drive unit 80 is an example of a drive unit.
  • the motor 84 is composed of, for example, a stepping motor.
  • the motor 84 is provided with an encoder 86 for detecting the rotation speed thereof.
  • the speed reducer 88 has a gear train.
  • the gear train is composed of a combination of a plurality of gears 88A to 88F.
  • the speed reducer 88 of the present embodiment includes a worm gear as a part of the gear train.
  • the worm gear is composed of a worm and a worm wheel.
  • the gear 88A connected to the output shaft of the motor 84 is composed of a worm.
  • the final gear 88F constitutes a drive gear.
  • the torque applying mechanism 100 applies a load torque to the rotation of the cam cylinder 16. As shown in FIG. 4, the torque applying mechanism 100 urges the torque applying roller 102 provided in the cam cylinder 16, the urging ring 104 that is pressed against the torque applying roller 102, and the urging ring 104. It has a urging spring 106 and a spring support frame 108 that supports the urging spring 106.
  • the torque applying roller 102 is composed of a cylindrical cylinder (so-called ordinary roller). As shown in FIG. 9, the torque applying roller 102 is supported by a roller support shaft 61 provided on the cam cylinder 16. More specifically, by fitting the roller support shaft 61 to the inner peripheral portion thereof, the roller support shaft 61 is mounted on the roller support shaft 61 and rotatably supported by the roller support shaft 61.
  • the roller support shaft 61 is also a shaft that supports the positioning roller 60.
  • the torque applying roller 102 is mounted on the positioning roller 60 on the roller support shaft 61 via the spacer 110.
  • the torque-applying roller 102 mounted on the roller support shaft 61 is rotatably supported by being prevented from coming off by the head portion 62A of the screw 62 that fixes the roller support shaft 61.
  • the torque applying roller 102 is only fitted to the roller support shaft 61, so that a load is generated during rotation. Specifically, a load is generated in rotation due to friction (rotational friction) between the inner peripheral portion of the torque applying roller 102 and the outer peripheral portion of the roller support shaft 61. Since friction is generated between the torque applying roller 102 and the roller support shaft 61 in this way, it is preferable to select a material that is resistant to wear for the torque applying roller 102 and the roller support shaft 61.
  • one of the torque applying roller 102 and the roller support shaft 61 may be made of stainless steel and the other may be made of brass.
  • the torque applying roller 102 may be made of resin. For example, a polyacetal product having excellent sliding characteristics can be used.
  • the torque applying roller 102 is an example of the first roller.
  • the urging ring 104 has a ring shape, is fitted to the outer peripheral portion of the second fixed cylinder 12B, and is attached to the outer peripheral portion of the second fixed cylinder 12B.
  • the urging ring 104 attached to the outer peripheral portion of the second fixed cylinder 12B is held so as to be movable back and forth along the optical axis Z.
  • the urging ring 104 can be, for example, made of alumite-processed aluminum.
  • the urging ring 104 is an example of the first frame.
  • the urging spring 106 is composed of a wave washer.
  • the urging spring 106 is attached to the outer peripheral portion of the second fixed cylinder 12B and urges the urging ring 104 toward the torque applying roller 102.
  • the urging spring 106 is an example of an urging member.
  • the spring support frame 108 is composed of a ring-shaped frame body.
  • the spring support frame 108 is fitted to the outer peripheral portion of the second fixed cylinder 12B and is attached to the outer peripheral portion of the second fixed cylinder 12B.
  • the spring support frame 108 mounted on the second fixing cylinder 12B is fixed to the second fixing cylinder 12B by screwing a plurality of locations on the peripheral surface with screws 108A.
  • the spring support frame 108 is an example of the second frame.
  • the urging spring 106 is arranged between the spring support frame 108 and the urging ring 104, and urges the urging ring 104 toward the torque applying roller 102. As a result, the urging ring 104 is pressed against the torque applying roller 102. Further, when the urging ring 104 presses against the torque applying roller 102, a load torque is applied to the rotation of the cam cylinder 16. Further, when the urging ring 104 presses against the torque applying roller 102, the cam cylinder 16 is urged along the optical axis Z, and the backlash of the cam cylinder 16 with respect to the fixed cylinder 12 is removed.
  • the position detection mechanism of the second lens cylinder 18 is composed of an encoder 86 provided in the motor 84 and a photo interrupter 120 provided in the fixed cylinder 12.
  • the encoder 86 detects the rotation speed of the motor 84.
  • the photo interrupter 120 detects that the second lens cylinder 18 is located at the origin position.
  • the photo interrupter 120 is provided on the rear end cover 12C of the fixed cylinder 12.
  • the photo interrupter 120 detects the light-shielding portion 122 provided on the second lens cylinder 18 and detects that the second lens cylinder 18 is located at the origin position.
  • the position of the second lens cylinder 18 is detected by the following procedure.
  • the photo interrupter 120 detects that the second lens cylinder 18 is located at the origin position.
  • the rotation speed of the motor 84 after the detection is detected by the encoder 86.
  • the position of the second lens cylinder 18 with respect to the origin position is detected. That is, since the amount of movement of the second lens cylinder 18 with respect to the rotation speed of the motor 84 is known, the position of the second lens cylinder 18 with respect to the origin position can be detected by detecting the rotation speed of the motor 84 from the origin position.
  • the second lens group L2 which is a focus lens group
  • the second lens group L2 moves back and forth along the optical axis Z to adjust the focus. ..
  • the rotation of the motor 84 is transmitted to the cam cylinder 16, and the rotation of the cam cylinder 16 causes the second lens cylinder to hold the second lens group L2 by the action of the cam. 18 moves back and forth along the optical axis Z.
  • the rotation of the motor 84 is transmitted to the cam cylinder 16 via the gear train. Therefore, the stop position of the second lens cylinder 18 becomes unstable within the range of the backlash due to the influence of the inertial force and gravity of the movable portion when stopping.
  • the interchangeable lens 1 of the present embodiment is provided with the torque applying mechanism 100, high stopping accuracy can be ensured. That is, since the load torque is applied to the rotation of the cam cylinder 16 by the torque applying mechanism 100, the second lens cylinder 18 can be stably stopped even if there is play in the meshing portion of the gear. ..
  • the load torque is given as follows.
  • the cam cylinder 16 is provided with a torque applying roller 102.
  • the urging ring 104 urged by the urging spring 106 is pressed against the torque applying roller 102.
  • the torque applying roller 102 rolls along the urging ring 104.
  • rotational friction is generated between the inner circumference of the torque applying roller 102 and the outer circumference of the roller support shaft 61. This rotational friction acts as a load torque for the cam cylinder 16.
  • the second lens cylinder 18 can be stably stopped. Further, since the load torque is generated by the rotational friction of the torque applying roller 102, it can always be applied in a stable state.
  • the torque applying mechanism 100 also has a function of removing the backlash of the cam cylinder 16. That is, by urging the torque applying roller 102 provided coaxially with the positioning roller 60 in the optical axis direction with the urging ring 104, the positioning roller 60 is pressed against the inner wall surface of the positioning groove 70. As a result, the play of the cam cylinder 16 with respect to the fixed cylinder 12 can be removed. Further, by sharing the positioning roller 60 and the shaft (roller support shaft 61), the configuration can be simplified.
  • the load torque is set to a value that can suppress rotation due to inertial force and gravity.
  • the torque required to stop the cam cylinder at the set deceleration is T1
  • the second lens cylinder is driven in the direction of falling by its own weight with the lens facing downward or upward
  • the second lens cylinder is set at the set deceleration.
  • the load torque TF is set so as to satisfy the following conditional expression.
  • FIG. 13 is an explanatory diagram of a calculation method of torques T1, T2 and T3.
  • Torque T1 The torque T1 [N ⁇ m] is calculated by the following equation.
  • T1 I ⁇ AC
  • I is the moment of inertia I of the cam cylinder
  • AC is the deceleration of the cam cylinder [rad / s 2 ].
  • the deceleration AC [rad / s 2 ] of the cam cylinder is calculated by the following equation.
  • FR a rotational component force [N] of the cam cylinder, as shown in FIG. Further, R is the distance [m] from the center of rotation to the cam groove.
  • the rotational component force FR [N] of the cam cylinder is calculated by the following equation.
  • FR tan ( ⁇ ) ⁇ FL
  • ⁇ is a cam angle [rad] as shown in FIG.
  • the FL is a force [N] required to decelerate the second lens cylinder when the lens is turned downward or upward and the second lens cylinder is driven in a direction in which the second lens cylinder falls by its own weight.
  • FL [N] is calculated by the following equation.
  • M [Kg] is the total weight of the second lens cylinder including the second lens group.
  • AL is the deceleration of the second lens barrel [rad / s 2 ].
  • AL [rad / s 2 ] is calculated by the following formula.
  • AM AM x L
  • AM is the deceleration of the motor [rad / s 2 ].
  • L is a cam lead [m / rad].
  • Cam lead is the amount of movement that advances to 1 [rad].
  • W is a load [N] perpendicular to the friction surface.
  • ⁇ is the coefficient of dynamic friction of the friction surface.
  • RM is a distance [m] from the center of rotation of the friction surface.
  • the load applied to the torque applying roller 102, the dynamic friction coefficient between the torque applying roller 102 and the roller support shaft 61, and the like are set so that the load torque TF satisfies the above conditions.
  • the load applied to the torque applying roller 102 can be adjusted by the spring constant (force amount of the urging spring) of the urging spring 106.
  • the dynamic friction coefficient can be adjusted by adjusting the material, surface roughness, etc. of the torque applying roller 102 and the roller support shaft 61.
  • the load torque TF When the load torque TF satisfies the above conditions, it can stop faster than the deceleration of the motor set by the drive control of the lens and maintain the state. As a result, stable position accuracy can be ensured.
  • the load torque TF By setting the load torque TF as small as possible within the range satisfying the above conditions, both the drive speed and the stop accuracy are realized.
  • FIG. 14 is a diagram showing a first modification of the torque applying mechanism.
  • the torque applying roller (first roller) 102 and the positioning roller (second roller) 60 share the roller support shaft 61.
  • the torque applying roller 102 is composed of bearings (roller bearings, etc.), and the positioning roller 60 is a so-called normal.
  • the same effect can be obtained even when the roller (cylindrical cylinder) is used.
  • the inner peripheral surface of the positioning roller 60 and the outer peripheral surface of the roller support shaft 61 function as friction surfaces. That is, the frictional force generated between the inner peripheral surface of the positioning roller 60 and the outer peripheral surface of the roller support shaft 61 acts as a load torque.
  • FIG. 15 is a diagram showing a second modification of the torque applying mechanism.
  • both the torque applying roller 102 and the positioning roller 60 are composed of ordinary rollers. In this case as well, the same effect can be obtained.
  • the inner peripheral surfaces of the torque applying roller 102 and the positioning roller 60 and the outer peripheral surface of the roller support shaft 61 function as friction surfaces.
  • FIG. 16 is a diagram showing a third modification of the torque applying mechanism.
  • the figure shows an example in which the torque applying roller 102 is supported by a dedicated shaft (roller support shaft).
  • the roller support shaft 112 that supports the torque applying roller 102 is provided in the cam cylinder 16.
  • the roller support shaft 112 has a cylindrical shape, and a screw 66 is passed through a hollow portion to screw the cam cylinder 16.
  • the cam cylinder 16 is provided with a screw hole 58 at a position where the roller support shaft 102A is attached.
  • the second fixed cylinder 12B is provided with a groove 72 through which the roller support shaft 102A is passed. The groove 72 is arranged along the circumferential direction.
  • the torque applying roller 102 can be provided separately from the positioning roller 60.
  • the configuration can be simplified.
  • the spring support frame 108 which is the support portion of the urging spring 106, is attached to the second fixing cylinder 12B with the screw 108A, but the supporting portion of the urging spring 106 is the second fixing cylinder 12B. It may be configured to be integrally provided with.
  • FIG. 17 is a diagram showing a modified example of the support portion of the urging spring.
  • the second fixed cylinder 12B has a flange portion 12b on the outer peripheral portion, and the flange portion 12b functions as a support portion of the urging spring 106.
  • the urging spring 106 is arranged between the urging ring 104 and the flange portion 12b, and urges the urging ring 104 in the direction of the torque applying roller 102 along the optical axis Z.
  • FIG. 17 shows an example in which the torque applying roller 102 is urged from the front side. That is, the urging ring 104 is arranged on the front side of the torque applying roller 102, and the torque applying roller 102 is urged from the front side. In this way, the torque applying roller 102 may be urged from the front side.
  • the urging spring 106 is composed of a wave washer, but the configuration of the urging spring is not limited to this. In addition, for example, it may be configured by a coil spring or the like.
  • the load torque applied by the torque applying mechanism 100 can also be adjusted by the number of installed torque applying rollers 102. That is, the number of torque applying rollers 102 installed is increased or decreased according to the required load torque.
  • FIG. 18 is an explanatory diagram of a method of adjusting the load torque by adjusting the number of installed torque applying rollers. The figure shows an example in which one of the three torque applying rollers 102 is replaced with a bearing.
  • the load torque can be adjusted by replacing the roller constituting the positioning roller 60 with a normal roller.
  • the second lens cylinder 18 is driven by a pair of cam followers 30A and 30B and a pair of cam grooves 40A and 40B, but one cam follower and one cam groove. It may be configured to be driven by.
  • FIG. 19 is a cross-sectional view showing an overall schematic configuration of the interchangeable lens of the second embodiment.
  • the interchangeable lens 1 of the present embodiment has a configuration of the second lens cylinder 18 different from that of the interchangeable lens of the first embodiment.
  • the second lens cylinder 18 is configured to shield the openings of the pair of cam grooves 40A and 40B provided in the cam cylinder 16 in the entire range of motion thereof. That is, it is configured to shield the openings of the pair of cam grooves 40A and 40B at any position.
  • FIG. 20 shows the relationship between the cam cylinder and the second lens cylinder when the second lens cylinder is moved to the frontmost side in the interchangeable lens of the first embodiment. It is a figure shown. Further, FIG. 21 is a diagram showing the relationship between the cam cylinder and the second lens cylinder when the second lens cylinder is moved to the rearmost side in the interchangeable lens of the first embodiment. In the figure, the broken line indicates the cam cylinder 16, and the solid line indicates the second lens cylinder 18. Further, in the figure, the cam follower is omitted for convenience.
  • FIG. 22 is a diagram showing the relationship between the cam cylinder and the second lens cylinder when the second lens cylinder is moved to the frontmost side in the interchangeable lens of the present embodiment.
  • FIG. 23 is a diagram showing the relationship between the cam cylinder and the second lens cylinder when the second lens cylinder is moved to the rearmost side in the interchangeable lens of the present embodiment.
  • the broken line indicates the cam cylinder 16
  • the solid line indicates the second lens cylinder 18.
  • the cam follower is omitted for convenience.
  • the pair of cam grooves 40A and 40B provided in the cam cylinder 16 are both first.
  • the opening is shielded by the two lens cylinder 18.
  • the pair of cam grooves 40A and 40B provided in the cam cylinder 16 are both provided by the second lens cylinder 18. The opening is shielded.
  • the openings of the pair of cam grooves 40A and 40B are shielded by the second lens cylinder 18 in the entire range of motion of the second lens cylinder 18.
  • the friction powder can be prevented from entering, so that it works effectively.
  • the openings of the cam grooves 40A and 40B are opened in the entire range of motion.
  • the fitting portion is configured to overlap the cam grooves 40A and 40B.
  • the opening of the first cam groove 40A is shielded by adjusting the length of the movable portion 18B.
  • the function can be realized.
  • the present invention is applied to the interchangeable lens of the interchangeable lens camera has been described as an example, but the application of the present invention is not limited to this.
  • it can be applied to the lens barrel of a lens-integrated camera (a camera in which a lens is integrally provided in the camera body).
  • a lens barrel such as a microscope or a telescope.
  • cameras include various cameras such as video cameras, TV cameras, and cine cameras, as well as devices equipped with camera functions (for example, mobile phones with cameras, smartphones, tablet computers, etc.). included.
  • the drive unit is built in the lens barrel
  • the drive unit may be provided outside the lens barrel.
  • a drive unit motor
  • rotational power is obtained from the camera body side
  • the cam cylinder is rotationally driven.
  • the drive unit is composed of a motor with a so-called speed reducer, but the configuration of the drive unit is not limited to this.
  • the stop position of the second lens cylinder 18 becomes unstable within the backlash range due to the influence of the inertial force and gravity of the moving part when stopping. Therefore, the present invention works particularly effectively.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Lens Barrels (AREA)
PCT/JP2020/028073 2019-07-24 2020-07-20 鏡胴 Ceased WO2021015166A1 (ja)

Priority Applications (3)

Application Number Priority Date Filing Date Title
CN202080052464.0A CN114174884B (zh) 2019-07-24 2020-07-20 镜筒
JP2021534026A JP7108142B2 (ja) 2019-07-24 2020-07-20 鏡胴
US17/564,866 US12313901B2 (en) 2019-07-24 2021-12-29 Lens barrel

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2019135988 2019-07-24
JP2019-135988 2019-07-24

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US17/564,866 Continuation US12313901B2 (en) 2019-07-24 2021-12-29 Lens barrel

Publications (1)

Publication Number Publication Date
WO2021015166A1 true WO2021015166A1 (ja) 2021-01-28

Family

ID=74192978

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2020/028073 Ceased WO2021015166A1 (ja) 2019-07-24 2020-07-20 鏡胴

Country Status (4)

Country Link
US (1) US12313901B2 (https=)
JP (1) JP7108142B2 (https=)
CN (1) CN114174884B (https=)
WO (1) WO2021015166A1 (https=)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11480756B2 (en) * 2020-12-14 2022-10-25 Karl Storz Imaging, Inc. Two-speed focusing mechanism
CN113671661B (zh) * 2021-08-19 2024-07-26 青岛睿维申信息科技有限公司 物镜调焦机构
US20240048831A1 (en) * 2022-08-02 2024-02-08 Shenzhen Dongzheng Optical Technology Co., Ltd Tele-converter structure with adjustable back focal length
US12436353B2 (en) * 2022-08-12 2025-10-07 Sphere Entertainment Group, Llc Camera lens flexure collar
JP7805976B2 (ja) * 2023-02-02 2026-01-26 キヤノン株式会社 光学装置及び撮像装置

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008224949A (ja) * 2007-03-12 2008-09-25 Nidec Copal Corp レンズ鏡胴
JP2009075328A (ja) * 2007-09-20 2009-04-09 Fujifilm Corp レンズ鏡筒
JP2009162822A (ja) * 2007-12-28 2009-07-23 Nidec Copal Corp レンズ鏡筒
JP2013257369A (ja) * 2012-06-11 2013-12-26 Canon Inc 光学装置
JP2014035438A (ja) * 2012-08-08 2014-02-24 Canon Inc エンコーダ、レンズ装置、および、カメラ

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002277712A (ja) * 2001-03-21 2002-09-25 Asahi Optical Co Ltd レンズガイド機構
US7039311B2 (en) * 2002-08-27 2006-05-02 Pentax Corporation Rotation transfer mechanism and a zoom camera incorporating the rotation transfer mechanism
JP2005134588A (ja) * 2003-10-30 2005-05-26 Kowa Co レンズ鏡筒
JP4722567B2 (ja) * 2005-05-31 2011-07-13 Ｈｏｙａ株式会社 レンズ鏡筒のばね張設構造
JP5079277B2 (ja) * 2006-07-20 2012-11-21 Ｈｏｙａ株式会社 レンズ鏡筒
JP5414417B2 (ja) 2009-08-07 2014-02-12 キヤノン株式会社 ズームレンズ鏡筒
JP2011133592A (ja) 2009-12-24 2011-07-07 Panasonic Corp レンズ鏡筒
JP5677039B2 (ja) * 2010-11-08 2015-02-25 キヤノン株式会社 レンズ鏡筒および撮像装置
JP2015040942A (ja) * 2013-08-21 2015-03-02 オリンパス株式会社 レンズ鏡筒、撮影装置、およびレンズ鏡筒の部品
JP2015166849A (ja) * 2014-01-06 2015-09-24 パナソニックＩｐマネジメント株式会社 レンズ鏡筒

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008224949A (ja) * 2007-03-12 2008-09-25 Nidec Copal Corp レンズ鏡胴
JP2009075328A (ja) * 2007-09-20 2009-04-09 Fujifilm Corp レンズ鏡筒
JP2009162822A (ja) * 2007-12-28 2009-07-23 Nidec Copal Corp レンズ鏡筒
JP2013257369A (ja) * 2012-06-11 2013-12-26 Canon Inc 光学装置
JP2014035438A (ja) * 2012-08-08 2014-02-24 Canon Inc エンコーダ、レンズ装置、および、カメラ

Also Published As

Publication number Publication date
JP7108142B2 (ja) 2022-07-27
CN114174884B (zh) 2023-08-01
CN114174884A (zh) 2022-03-11
US20220121000A1 (en) 2022-04-21
US12313901B2 (en) 2025-05-27
JPWO2021015166A1 (https=) 2021-01-28

Similar Documents

Publication Publication Date Title
JP7108142B2 (ja) 鏡胴
CN202301767U (zh) 齿轮机构及透镜镜筒
US8369024B2 (en) Lens driving device and electronic device
US6038404A (en) Lens barrel for a camera having a non-rotatable cam ring moved by a feed screw
JP6009468B2 (ja) レンズ鏡筒
JP2013257369A (ja) 光学装置
JP7203423B2 (ja) レンズ鏡筒
US10211701B2 (en) Driving apparatus and optical apparatus using the same
JPH0980289A (ja) テレビカメラの微調整レンズ駆動装置
JP2006234962A (ja) レンズ鏡筒
JP3766379B2 (ja) フォーカス調整装置、光学機器
JP2017027086A (ja) 光学装置
JP2007041151A (ja) レンズ駆動装置
JPH1114885A (ja) レンズ鏡筒
JPS62226112A (ja) 三脚座を有するレンズの駆動装置
JP6759622B2 (ja) 光学要素の固定構造
JP2016114858A (ja) レンズ鏡筒および光学機器
JP2002258134A (ja) レンズ鏡筒
US20230314758A1 (en) Lens apparatus and imaging apparatus
JP2787244B2 (ja) 二軸レンズ駆動装置
JP2002318337A (ja) カム機構及びレンズ装置
JPH0384508A (ja) ブレ補正鏡胴
JP2024046058A (ja) 駆動装置、光学システム及び撮像システム
JPH0384506A (ja) ブレ補正鏡胴
JP6170764B2 (ja) ベルト寄り調整機構

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20843994

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 2021534026

Country of ref document: JP

Kind code of ref document: A

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 20843994

Country of ref document: EP

Kind code of ref document: A1