JP2005215546A - Optical device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To restore a lens unit pushed to an image surface side by external force to an original state after the external force is removed. <P>SOLUTION: The optical device has a 1st driving member 24 driven by an actuator 22, a 1st lens holding member 19 and a 2nd lens holding member 21, and a 2nd driving member 26 moved by receiving driving force from the 1st driving member. Furthermore, the device has a 1st energizing means 27 for energizing the 2nd driving member in an object direction, a 2nd energizing means 29 for energizing the 2nd holding member in an image surface direction, and a 3rd energizing means 28 for energizing the 1st holding member in the object direction. The 2nd driving member does not abut on the 1st holding member but abuts on the 2nd holding member when it is positioned in a 1st area, and it does not abut on the 2nd holding member but abuts on the 1st holding member when it is positioned in a 2nd area nearer to the image surface side than the 1st area. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an optical device that moves a plurality of lens units in the optical axis direction.

  As an optical device that moves a plurality of lens units in the optical axis direction, there is one shown in FIG. 11 (see Patent Document 1).

  In FIG. 11, 1 is a front lens that is fixed at the time of photographing, 2 is a front lens holding frame that holds the front lens 1, and 3 is a front lens holding frame 2 that is movable in the optical axis direction. And it is a fixed barrel which restricts the rotation. A rack 6 is attached to the front lens holding frame 2 via an elastic member 7, and a pinion gear 8 drives the rack 6 in the optical axis direction.

  When the pinion gear 8 is driven by a drive source (not shown), the front lens holding frame 2 is driven in the optical axis direction via the rack 6 and the elastic member 7. As a result, the front lens holding frame 2 can be protruded toward the object side with respect to the fixed barrel 3 and retracted to the image plane side.

As shown in FIG. 11, when the front lens holding frame 2 protrudes most toward the object side with respect to the fixed lens barrel 3, the abutment surface 5 provided on the front lens holding frame 2 becomes the protrusion 4 of the fixed lens tube 3. The front lens holding frame 2 is prevented from moving further toward the object side.
JP-A-8-179188 (paragraphs 0016 to 0019, FIG. 1, FIG. 3, etc.)

  However, in the optical apparatus shown in FIG. 11, since the front lens holding frame 2 is directly extended by the pinion gear 8, when the external force in the image plane direction is applied to the front lens 1, the pinion gear 8 is rotated. However, even if the engagement between the pinion gear 8 and the rack 6 is disengaged and the front lens holding frame 2 (front lens 1) is moved to the image plane side, and the external force disappears thereafter, the position of the front lens is restored. There is no possibility.

  In addition, the optical device shown in FIG. 11 requires an actuator for retracting driving in addition to an actuator for optical operations such as zooming and focus adjustment, which may increase the size of the device.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an optical device in which a lens unit pushed into an image plane side by an external force can be restored after the external force is lost, and the size can be reduced by reducing the number of actuators. .

  In order to achieve the above object, an optical device of the present invention holds an actuator, a first driving member driven in the optical axis direction by the actuator, and a first lens unit, and moves in the optical axis direction. A first holding member that is possible, a second holding member that holds the second lens unit disposed closer to the image plane than the first lens unit, and is movable in the optical axis direction; The second holding member can be brought into contact with the second holding member in the optical axis direction, and has a second driving member that receives the driving force from the first driving member and moves in the optical axis direction. Further, a first urging means for urging the second driving member toward the first driving member in the object direction, and a urging of the second holding member toward the second driving member in the image plane direction And a third urging means for urging the first holding member toward the apparatus main body in the object direction. When the second driving member is located in the first region in the optical axis direction, the second driving member does not contact the first holding member and contacts the second holding member. When it is located in the second area on the image plane side, it does not contact the second holding member and contacts the first holding member.

  According to the present invention, the first and second lens units are moved by moving the second driving member between the first region and the second region closer to the image plane than the first driving member by the driving force of one actuator. Among them, an operation for moving only the second lens unit (for example, an optical operation such as zooming and focus adjustment) and an operation for moving only the first holding member (for example, an operation for projecting and storing with respect to the apparatus main body). Both can be done. In addition, since the first holding member that holds the first lens unit is biased toward the object side, if the first holding member is pushed to the image plane side by an external force and the external force disappears, One holding member can be returned to its original position by the biasing force.

  Here, when the second driving member is located in the first region, the first holding member abuts on the apparatus main body by the biasing force of the third biasing means, and the second driving member is the second driving member. The second holding member may be configured to abut against the apparatus main body by the urging force of the second urging means. Accordingly, when the second drive member moves in the first region, the first holding member is moved to a predetermined position (for example, a position that contacts the contact portion of the apparatus main body and protrudes from the apparatus main body to the object side). The second holding member can be moved while being stopped at the same time, and when the second driving member moves in the second region, the second holding member is moved to a predetermined position (for example, in the apparatus main body). The first holding member can be moved from the predetermined position on the image plane side while being stopped at the storage position in FIG.

  Further, the number of parts can be reduced by combining the second urging means and the third urging means with a single urging means.

  In addition, by appropriately setting the relationship between the urging forces of the first to third urging means and the relationship between the relative movable lengths of the respective members, proper operation of each member can be ensured, It is possible to prevent an external force acting on one holding member (first lens unit) in the image plane direction from being transmitted to the first driving member driven by the actuator.

  Embodiments of the present invention will be described below with reference to the drawings.

  1 to 4 show the configuration of a lens apparatus that is Embodiment 1 of the present invention. This lens apparatus is used for an imaging apparatus such as a digital camera or a video camera. FIG. 1 is a cross-sectional view showing a wide state of the lens apparatus, and FIG. 2 is a cross-sectional view showing a tele state. The state from the state of FIG. 1 to the state of FIG. 2 (including the intermediate state) is hereinafter referred to as a photographing state. 3 is a cross-sectional view showing a retracted state in which the lens apparatus is housed in the camera body 10, and the state from the state of FIG. 2 to the state of FIG. . Furthermore, FIG. 4 is a cross-sectional view showing a state in which the front ball is pushed in by the external force in the wide state.

  In these drawings, 11 is a fixed barrel fixed to the camera body 10, and 12 is a bar pressing member fixed to the fixed barrel 11 by screws 13. The fixed barrel 11 and the bar pressing member 12 constitute a main body of the present lens device.

  Reference numerals 14, 15, 16, and 17 denote guide bars that are sandwiched and fixed between the fixed barrel 11 and the bar pressing member 12.

  Reference numeral 18 denotes a first lens unit that is arranged closest to the object side among four lens units described later, is fixed in the optical axis direction in the shooting state, and moves to the image plane side in the non-shooting state. Reference numeral 19 denotes a first lens holding barrel that holds the first lens unit 18. The first lens holding barrel 19 is engaged with the guide bar 14 so as to be movable in the optical axis direction, and is similarly engaged with the guide bar 17 to prevent rotation about the guide bar 14. .

  Reference numeral 20 denotes a second lens unit that is disposed on the image plane side of the first lens unit 18 and moves in the optical axis direction to change the magnification. Reference numeral 21 denotes a second lens holding barrel that holds the second lens unit 20. The second lens holding barrel 21 is engaged with the guide bar 15 so as to be movable in the optical axis direction, and is similarly engaged with the guide bar 17 to prevent rotation about the guide bar 15. .

  Reference numeral 22 denotes a first stepping motor (actuator) which is fixed to the fixed barrel 11 by a screw 46 and moves the first lens unit 18 and the second lens unit 20 in the optical axis direction. Reference numeral 23 denotes a first rack that meshes with a feed screw portion (hereinafter referred to as a first feed screw portion) 22a of the first stepping motor 22 and is driven in the optical axis direction by the rotation of the first feed screw portion 22a.

  Reference numeral 24 denotes a rectilinear drive member (first drive member) that engages with the guide bar 16 so as to be movable in the optical axis direction, and similarly engages with a guide bar (not shown) to center the guide bar 16. Rotation is prevented.

  Reference numeral 25 denotes a first rack spring that urges the first rack 23 in the direction of meshing with the first feed screw portion 22 a and urges (shifts) the linear rack toward the rectilinear drive member 24 in the image plane direction. Reference numeral 26 denotes a lens barrel driving member (second driving member) that engages with the guide bar 16 so as to be movable in the optical axis direction, and similarly engages with a guide bar (not shown) to center the guide bar 16. Rotation is blocked.

  A first spring (first attachment) 27 is disposed between the lens barrel drive member 26 and the rectilinear drive member 24 and urges the lens barrel drive member 26 toward the rectilinear drive member 24 in the object direction. Force). In the state of FIGS. 1 to 3, the third abutting portion 26 c of the lens barrel driving member 26 abuts against the abutting portion 24 a of the rectilinear drive member 24 by the urging force of the first spring 27. In this state, the lens barrel drive member 26 and the rectilinear drive member 24 move integrally. Then, when the first spring 27 is compressed and deformed, the lens barrel driving member 26 and the rectilinear driving member 24 can move relatively. The length that the lens barrel drive member 26 and the rectilinear drive member 24 can move relative to each other is L3.

  Reference numeral 28 denotes a third spring (between the first lens holding barrel 19 and the fixed barrel 11) that urges (shifts) the first lens holding barrel 19 toward the bar pressing member 12 in the object direction. Third urging means). In the state of FIGS. 1 and 2, the first abutting portion 19 a of the first lens holding barrel 19 abuts against the abutting portion 12 a of the bar pressing member 12 by the urging force of the third spring 28, and the first lens holding is performed. A cylindrical portion of the lens barrel 19 that holds the first lens unit 18 protrudes from the bar pressing member 12 (that is, the camera body 10).

  Further, the first lens holding barrel 19 and the barrel driving member 26 can move relative to each other. The relative movable length between the first lens holding barrel 19 and the barrel driving member 26 is L1. L1 is set to be equal to or longer than the length of movement of the second lens holding barrel 21 for zooming.

  Further, in the state of FIG. 3 from the state of FIG. 2, the first abutting portion 26 a of the lens barrel driving member 26 contacts the second abutting portion 19 b of the first lens holding lens barrel 19, and the lens barrel driving member 26 and The first lens holding barrel 19 moves integrally.

  29 is disposed between the second lens holding barrel 21 and the barrel driving member 26, and urges (shifts) the second lens holding barrel 21 toward the barrel driving member 26 in the image plane direction. Two springs (second urging means). In the state of FIG. 1 to FIG. 2, the first abutting portion 21 a of the second lens holding barrel 21 abuts on the second abutting portion 26 b of the barrel driving member 26 by the urging force of the second spring 29, and the second The lens holding barrel 21 and the barrel driving member 26 are integrally moved in the optical axis direction.

  When the movable length of the second lens holding barrel 21 is L2, this L2 is set to be equal to or longer than the length that the second lens holding barrel 21 moves for zooming, L2 is set to be the same as or shorter than L3.

  Reference numeral 30 denotes a fixed third lens unit disposed on the image plane side of the second lens unit 20, and 31 denotes a third lens holding barrel that holds the third lens unit 30. The third lens holding barrel 31 is fixed to the fixed barrel 11.

  Reference numeral 32 denotes an aperture unit fixed to the fixed lens barrel 11 with a screw 33, and 34 denotes a guide bar fixed between the fixed lens barrel 11 and the third lens holding lens barrel 31.

  Reference numeral 35 denotes a fourth lens unit which is disposed on the image plane side with respect to the third lens unit 30 and moves in the optical axis direction for image plane movement and focus adjustment accompanying zooming.

  Reference numeral 36 denotes a fourth lens holding barrel that holds the fourth lens unit 35. The fourth lens holding barrel 36 engages with the guide bar 34 so as to be movable in the optical axis direction, and similarly engages with a guide bar (not shown) to prevent rotation about the guide bar 34. Has been.

  Reference numeral 37 denotes a second stepping motor which is fixed to the fixed barrel 11 by a screw 38 and moves the fourth lens holding barrel 36 in the optical axis direction. Reference numeral 39 denotes a second rack that meshes with a feed screw portion (hereinafter referred to as a second feed screw portion) 37a of the second stepping motor 37 and moves in the optical axis direction by the rotation of the second feed screw portion 37a. Reference numeral 40 denotes a second rack spring that urges the second rack 39 in the direction of meshing with the second feed screw portion 37 a and urges (shifts) the object toward the fourth lens holding barrel 36.

  Reference numeral 41 denotes a low-pass filter fixed to the fixed barrel 11, and 42 denotes an image sensor pressing plate fixed to the fixed barrel 11 with screws 43. Reference numeral 44 denotes an image pickup element (photoelectric conversion element) such as a CCD or CMOS sensor fixed to the image pickup element holding plate 42, and 45 denotes an elastic member such as rubber sandwiched between the low-pass filter 41 and the image pickup element 44.

  Next, the operation of the lens device will be described. When the first stepping motor 22 is driven from the wide state shown in FIG. 1 and the first feed screw portion 22a is rotated in the first direction, the first rack 23 is moved in the image plane direction, and the rectilinear drive member 24 and the lens barrel are moved. The driving member 26 integrally moves in the image plane direction.

  Here, since the first lens holding barrel 19 is biased in the object direction by the third spring 28 so as to contact the abutting portion 12a of the bar pressing member 12, the first abutting portion of the barrel driving member 26 is provided. 26a does not abut against the second abutting portion 19b of the first lens holding barrel 19 (until the first abutting portion 26a abuts against the second abutting portion 19b) in the section (first region) of L1. The first lens holding barrel 19 does not move from the state shown in FIG.

  On the other hand, while the first abutting portion 26a of the lens barrel driving member 26 moves in the image plane direction in the section L1, the first abutting portion 21a of the second lens holding barrel 21 is the second abutting portion of the lens barrel driving member 26. Since the second lens holding lens barrel 21 is pressed against the abutting portion 26 b by the urging force of the second spring 29, the second abutting portion 21 b of the second lens holding lens barrel 21 is an image of the fixed lens barrel 11. The lens barrel drive member 26 moves in the same direction as the lens barrel drive member 26 moves in the image plane direction until it hits the abutting portion 11a formed at the end on the surface side. As shown in FIG. 2, the telescopic state is a state where the second abutting portion 21 b of the second lens holding barrel 21 abuts against or abuts against the abutting portion 11 a of the fixed barrel 11.

  Further, when the first feed screw portion 22a of the first stepping motor 22 is rotated in the first direction from the telephoto state shown in FIG. 2, the first abutting portion 26a of the lens barrel driving member 26 becomes the first lens holding mirror. The first lens holding barrel 19 is stored inside the fixed barrel 11 and the bar pressing member 12 as shown in FIG. 3 while hitting the second abutting portion 19b of the barrel 19 and pushing it in the image plane direction. The first lens holding barrel 21 is moved in the image plane direction against the urging force of the third spring 28 in the interval up to (second region). Thereby, it will be in a retracted state.

  At this time, the second abutting portion 21b of the second lens holding barrel 21 is pressed against the abutting portion 11a of the fixed barrel 11 by the urging force of the second spring 29. The abutting portion 26b moves away from the first abutting portion 21a of the second lens holding barrel 21 in the image plane direction, and the second lens holding barrel 21 does not move.

  When the first stepping motor 22 rotates in the second direction opposite to the first direction from the retracted state of FIG. 3, the second abutting portion 26 b of the lens barrel driving member 26 is the second lens holding lens barrel 21. The first lens holding member 19 is moved in the object direction until immediately before contacting the first abutting portion 21a (second region). As shown in FIG. 2, the first abutting portion 19 a of the first lens holding member 19 abuts against the abutting portion 12 a of the bar pressing member 12, and the second abutting portion 26 b of the lens barrel driving member 26 is After contacting the first abutting portion 21a of the second lens holding barrel 21 (first region), the second lens holding barrel 21 is driven in the object direction by the barrel driving member 26.

  Thus, when the lens barrel driving member 26 moves within the section L1 (first region), the lens barrel driving member 26 does not come into contact with the first lens holding lens barrel 19 and the first lens holding mirror. Although the barrel 19 is not moved, the barrel drive member 26 contacts the second lens holding barrel 21 and moves the second lens holding barrel 21. On the other hand, when the lens barrel driving member 26 moves in the section (second region) closer to the image plane than the section of L1, the lens barrel driving member 26 does not contact the second lens holding barrel 21, Although the second lens holding barrel 21 is not moved, the barrel driving member 26 abuts on the first lens holding barrel 19 and moves the first lens holding barrel 19.

  When the second stepping motor 37 is driven to rotate the second feed screw portion 37a in the first direction, the second rack 39 moves in the image plane direction, and the fourth lens holding barrel 36 (fourth lens unit) is moved. 35) moves in the image plane direction. Further, by rotating the second feed screw portion 37a in the second direction opposite to the first direction, the second rack 39 and the fourth lens holding barrel 36 (fourth lens unit 35) move in the object direction. .

  The lens barrel driving member 26 is moved in the section L1 (and in the section L2) to move the second lens unit 20 in the optical axis direction with the first lens unit 18 fixed, and the fourth lens unit. Zooming can be performed by moving 35 in the optical axis direction. In addition, focus adjustment can be performed by moving the fourth lens unit 35 in the optical axis direction.

  Further, when an external force F1 in the image plane direction is applied to the first lens unit 18 (or the first lens holding barrel 19) in the state of FIG. 1, the first lens unit 18 resists the urging force of the third spring 28. Move in the image plane direction. In the middle of this, the third abutting portion 19c of the first lens holding barrel 19 abuts against the third abutting portion 21c of the second lens holding barrel 21, so that the second lens holding barrel 21 and this The lens barrel drive member 26 in contact also moves in the image plane direction together with the first lens holding barrel 19 against the urging force of the first and third springs 27 and 28.

  Here, since L3 has a length equal to or longer than L2, as shown in FIG. 4, the image surface until the second butting portion 21b of the second lens holding barrel 21 strikes the butting portion 11a of the fixed barrel 11. Even if it moves in the direction, the positions of the rectilinear drive member 24 and the first rack 23 do not change. Therefore, the engagement between the first rack 23 and the first feed screw portion 22a is not released.

  When the external force F1 disappears, the first lens holding barrel 19 and the second lens holding barrel 21 return to their original positions (positions shown in FIG. 1) by the urging forces of the first and third springs 27 and 28. be able to.

  In the present embodiment, when the second lens unit 20 is moved in the optical axis direction within the section L2, the first to third springs 27 to 29 are not deformed. It can be moved regardless of the spring force. Therefore, the energy used for driving the first stepping motor 22 when performing the zooming operation can be reduced.

  5 and 6 show the configuration of a lens apparatus that is Embodiment 2 of the present invention. This lens apparatus is used for an imaging apparatus such as a digital camera or a video camera. FIG. 5 is a sectional view showing a wide state of the lens device. Hereinafter, the state from the state shown in FIG. 5 to the tele state (not shown) (including the intermediate state) is referred to as a photographing state. FIG. 6 is a cross-sectional view showing a retracted state in which the lens apparatus is housed in the camera body (see FIG. 1). The state from the tele state to the state of FIG. 6 (including the intermediate state) is not photographed. It is called a state.

  In these figures, 51 is a fixed barrel fixed to the camera body (see 10 in FIG. 1), and 52 is a bar pressing member fixed to the fixed barrel 51 by screws 53. The fixed lens barrel 51 and the bar pressing member 52 constitute a main body of the lens apparatus.

  Reference numerals 54, 55, 56, and 57 denote guide bars that are sandwiched and fixed between the fixed barrel 51 and the bar pressing member 52, respectively.

  Reference numeral 58 denotes a first lens unit that is disposed closest to the object side among four lens units described later, is fixed in the optical axis direction in the shooting state, and moves to the image plane side in the non-shooting state. Reference numeral 59 denotes a first lens holding barrel that holds the first lens unit 58. The first lens holding lens barrel 59 engages with the guide bar 54 so as to be movable in the optical axis direction, and similarly engages with the guide bar 57 to prevent rotation about the guide bar 54. .

  Reference numeral 60 denotes a second lens unit that is disposed on the image plane side of the first lens unit 58 and moves in the optical axis direction to change the magnification. Reference numeral 61 denotes a second lens holding barrel that holds the second lens unit 60. The second lens holding barrel 61 engages with the guide bar 55 so as to be movable in the optical axis direction, and similarly engages with the guide bar 57 to prevent rotation about the guide bar 55. .

  Reference numeral 62 denotes a first stepping motor (actuator) which is fixed to the fixed barrel 51 by a screw 86 and moves the first lens unit 58 and the second lens unit 60 in the optical axis direction. Reference numeral 63 denotes a first rack that meshes with a feed screw portion (hereinafter referred to as a first feed screw portion) 62a of the first stepping motor 62 and is driven in the optical axis direction by the rotation of the first feed screw portion 62a.

  Reference numeral 64 denotes a rectilinear drive member (first drive member) that engages with the guide bar 56 so as to be movable in the optical axis direction, and similarly engages with a guide bar (not shown) to center the guide bar 56. Rotation is prevented.

  Reference numeral 65 denotes a first rack spring that urges the first rack 63 in a direction to mesh with the first feed screw portion 62a and urges (shifts) the linear rack toward the rectilinear drive member 64 in the image plane direction. Reference numeral 66 denotes a lens barrel drive member (second drive member) that engages with the guide bar 66 so as to be movable in the optical axis direction, and similarly engages with a guide bar (not shown) to center the guide bar 56. Rotation is blocked.

  A first spring (first attachment) 67 is disposed between the lens barrel driving member 66 and the rectilinear driving member 64 and biases (shifts) the lens barrel driving member 66 toward the rectilinear driving member 64 in the object direction. Force). 5 to 6, the third abutting portion 66 c of the lens barrel driving member 66 abuts against the abutting portion 64 a of the rectilinear drive member 64 by the biasing force of the first spring 67. In this state, the lens barrel driving member 66 and the rectilinear driving member 64 move integrally. And the 1st spring 67 compressively deforms, and the lens-barrel drive member 66 and the rectilinear drive member 64 can move relatively. The length that the lens barrel drive member 66 and the rectilinear drive member 64 can move relative to each other is L3.

  A third spring 68 is disposed between the first lens holding lens barrel 59 and the lens barrel driving member 66, and urges (shifts) the first lens holding lens barrel 59 toward the bar pressing member 52 in the object direction. (Third urging means). In the state of FIG. 5 and the tele state, the first abutting portion 59a of the first lens holding barrel 59 abuts against the abutting portion 52a of the bar pressing member 52 by the urging force of the third spring 68, and the first lens holding A cylindrical portion of the lens barrel 59 that holds the first lens unit 58 protrudes from the bar pressing member 52 (that is, the camera body).

  Further, the first lens holding lens barrel 59 and the lens barrel driving member 66 can move relative to each other. The relative movable distance between the first lens holding barrel 59 and the barrel driving member 66 is L6. L6 is set to be equal to or longer than the length that the second lens holding barrel 61 moves for zooming.

  In the state from the telephoto state to the state shown in FIG. 6, the first abutting portion 66 a of the lens barrel driving member 66 contacts the second abutting portion 59 b of the first lens holding lens barrel 59, and the lens barrel driving member 66 and the first abutting portion 66 a. The lens holding barrel 59 moves integrally.

  69 is disposed between the bar pressing member 52 and the second lens holding barrel 61, and secondly biases (shifts) the second lens holding barrel 61 toward the barrel driving member 66 in the image plane direction. A spring (second biasing means). In the tele state from the state of FIG. 5, the first abutting portion 61 a of the second lens holding lens barrel 61 abuts on the second abutting portion 66 b of the lens barrel driving member 66 by the urging force of the second spring 69, and the second The lens holding barrel 61 and the barrel driving member 66 are integrally moved in the optical axis direction.

  Assuming that the movable length of the second lens holding barrel 61 is L5, this L5 is set to be equal to or longer than the length that the second lens holding barrel 61 moves for zooming. L5 is set to be the same as or shorter than L6.

  Reference numeral 70 denotes a fixed third lens unit disposed on the image plane side with respect to the second lens unit 60, and reference numeral 71 denotes a third lens holding barrel that holds the third lens unit 70. The third lens holding barrel 71 is fixed to the fixed barrel 51.

  Reference numeral 72 denotes a diaphragm unit fixed to the fixed lens barrel 51 by a screw 73, and 74 denotes a guide bar fixed by being sandwiched between the fixed lens barrel 71 and the third lens holding lens barrel 71.

  Reference numeral 75 denotes a fourth lens unit which is arranged on the image plane side with respect to the third lens unit 70 and moves in the optical axis direction for image plane movement and focus adjustment accompanying zooming.

  Reference numeral 76 denotes a fourth lens holding barrel that holds the fourth lens unit 75. The fourth lens holding barrel 76 engages with the guide bar 74 so as to be movable in the optical axis direction, and similarly engages with a guide bar (not shown) to prevent rotation about the guide bar 74. Has been.

  Reference numeral 77 denotes a second stepping motor which is fixed to the fixed barrel 51 by screws 78 and moves the fourth lens holding barrel 76 in the optical axis direction. Reference numeral 79 denotes a second rack which meshes with a feed screw portion (hereinafter referred to as a second feed screw portion) 77a of the second stepping motor 77 and moves in the optical axis direction by the rotation of the second feed screw portion 77a. Reference numeral 80 denotes a second rack spring that urges the second rack 79 in a direction to mesh with the second feed screw portion 77a and urges (shifts) the object toward the fourth lens holding barrel 76.

  Reference numeral 81 denotes a low-pass filter fixed to the fixed barrel 51, and 82 denotes an image sensor pressing plate fixed to the fixed barrel 51 with screws 83. Reference numeral 84 denotes an imaging element (photoelectric conversion element) such as a CCD or CMOS sensor fixed to the imaging element pressing plate 82, and 85 denotes an elastic member such as rubber sandwiched between the low-pass filter 81 and the imaging element 84.

  Next, the operation of the lens device will be described. When the first stepping motor 62 is driven from the wide state shown in FIG. 5 to rotate the first feed screw 62a in the first direction, the first rack 63 moves in the image plane direction, and the linear drive member 64 and the lens barrel are moved. The driving member 66 moves integrally in the image plane direction.

  Here, since the first lens holding barrel 59 is biased in the object direction by the third spring 68 so as to abut against the abutting portion 52a of the bar pressing member 52, the first abutting portion of the barrel driving member 66 is provided. 66a does not contact the second abutting portion 59b of the first lens holding barrel 59 (until the first abutting portion 66a abuts against the second abutting portion 59b) in the section (first region) of L4. The first lens holding barrel 59 does not move from the state shown in FIG.

  On the other hand, while the first abutting portion 66a of the lens barrel driving member 66 moves in the image plane direction in the section L4, the first abutting portion 61a of the second lens holding barrel 61 is the second abutting portion of the lens barrel driving member 66. Since the second lens holding barrel 61 is pressed against the abutting portion 66 b by the urging force of the second spring 69, the second abutting portion 61 b of the second lens holding barrel 61 is an image of the fixed barrel 51. The lens barrel drive member 66 moves in the same direction as the lens barrel drive member 66 moves in the image plane direction until it hits the abutting portion 51a formed at the end on the surface side. The state where the second abutting portion 61b of the second lens holding barrel 61 abuts against or abuts against the abutting portion 51a of the fixed barrel 51 is the tele state.

  Further, when the first feed screw portion 62a of the first stepping motor 62 is rotated in the first direction from the tele state, the first abutting portion 66a of the lens barrel driving member 66 is moved to the first lens holding lens barrel 59. 2 until the first lens holding lens barrel 59 is stored inside the fixed lens barrel 51 and the bar pressing member 52 as shown in FIG. In the second region, the first lens holding barrel 59 is moved in the image plane direction. Thereby, it will be in a retracted state.

  At this time, the second abutting portion 61b of the second lens holding barrel 61 is pressed against the abutting portion 51a of the fixed barrel 51 by the urging force of the second spring 69. The abutting portion 66b moves away from the first abutting portion 61a of the second lens holding barrel 61 in the image plane direction, and the second lens holding barrel 21 does not move.

  Further, when the first stepping motor 62 rotates in the second direction opposite to the first direction from the retracted state of FIG. 6, the second abutting portion 66b of the lens barrel driving member 66 has the second lens holding lens barrel 61. It moves in the object direction with the first lens holding member 59 until just before contacting the first abutting portion 61a (second region).

  In the tele state, the first butting portion 59a of the first lens holding member 59 abuts against the butting portion 52a of the bar pressing member 52, and the second butting portion 66b of the lens barrel driving member 66 is the second lens. After contacting the first abutting portion 61a of the holding barrel 61 (first region), the second lens holding barrel 21 is driven in the object direction by the barrel driving member 26.

  As described above, when the lens barrel driving member 66 moves within the section L4 (first region), the lens barrel driving member 66 does not contact the first lens holding lens barrel 59, and the first lens holding mirror. Although the tube 59 is not moved, the lens barrel driving member 66 abuts on the second lens holding barrel 61 and moves the second lens holding barrel 61. On the other hand, when the lens barrel driving member 66 moves within the section (second region) closer to the image plane than the section of L4, the lens barrel driving member 66 does not contact the second lens holding lens barrel 61, Although the second lens holding barrel 61 is not moved, the barrel driving member 66 abuts on the first lens holding barrel 59 and moves the first lens holding barrel 59.

  When the second stepping motor 77 is driven to rotate the second feed screw portion 77a in the first direction, the second rack 79 moves in the image plane direction, and the fourth lens holding barrel 76 (fourth lens unit) is moved. 75) moves in the image plane direction. Further, by rotating the second feed screw portion 77a in the second direction opposite to the first direction, the second rack 89 and the fourth lens holding barrel 76 (fourth lens unit 75) move in the object direction. .

  The lens barrel drive member 66 is moved within the section L4 (and within the section L5) to move the second lens unit 60 in the optical axis direction while the first lens unit 58 is fixed, and the fourth lens unit. Zooming can be performed by moving 75 in the optical axis direction. Further, the focus adjustment can be performed by moving the fourth lens unit 75 in the optical axis direction.

  Further, when an external force F2 in the image plane direction is applied to the first lens unit 58 (or the first lens holding barrel 59) in the state of FIG. 5, the first lens unit 58 resists the urging force of the third spring 68. Move in the image plane direction. On the way, the third abutting portion 59c of the first lens holding lens barrel 59 abuts against the third abutting portion 61c of the second lens holding lens barrel 61. The lens barrel drive member 66 in contact with the first lens 67 moves in the image plane direction together with the first lens holding lens barrel 59 against the urging force of the first spring 67.

  Here, since L6 has a length equal to or longer than L5, even if the second abutting portion 61b of the second lens holding barrel 61 moves in the image plane direction until it abuts against the abutting portion 51a of the fixed barrel 51, The positions of the rectilinear drive member 64 and the first rack 63 do not change. Accordingly, the engagement between the first rack 63 and the first feed screw portion 62a is not released.

  When the external force F2 disappears, the first lens holding barrel 59 and the second lens holding barrel 61 return to their original positions (positions shown in FIG. 5) by the urging forces of the first and third springs 67 and 68. be able to.

  In this embodiment, the urging force of the first spring 67 is the urging force obtained by adding the urging force of the third spring 68 and the urging force of the second spring 69 (from the bar pressing member 52 in the state shown in FIG. 5). The lens barrel driving member 66 is biased in the image plane direction by the reaction force of Thereby, the state (positional relationship of each member) shown in FIG. 5 is securable.

  FIG. 7 shows the configuration of a lens apparatus that is Embodiment 3 of the present invention. This lens apparatus is used for an imaging apparatus such as a digital camera or a video camera. FIG. 3 is a cross-sectional view showing a wide state of the lens device. The state from the state of FIG. 7 to the tele state (not shown) (including the intermediate state) is hereinafter referred to as a photographing state. Moreover, a retracted state (including an intermediate state) (not shown) from the tele state is referred to as a non-photographing state.

  In FIG. 7, 91 is a fixed barrel fixed to the camera body (see 10 in FIG. 1), and 92 is a bar pressing member fixed to the fixed barrel 91 by screws 93. The lens barrel 91 and the bar pressing member 92 constitute a main body of the lens apparatus.

  Reference numerals 94, 95, 96, and 97 denote guide bars that are sandwiched and fixed between the fixed barrel 91 and the bar pressing member 92.

  Reference numeral 98 denotes a first lens unit that is disposed closest to the object side among four lens units described later, is fixed in the optical axis direction in the shooting state, and moves toward the image plane side in the non-shooting state. Reference numeral 99 denotes a first lens holding barrel that holds the first lens unit 98. The first lens holding lens barrel 99 engages with the guide bar 94 so as to be movable in the optical axis direction, and similarly engages with the guide bar 97 to prevent rotation about the guide bar 94. .

  Reference numeral 100 denotes a second lens unit that is disposed on the image plane side with respect to the first lens unit 98 and moves in the optical axis direction to change the magnification. Reference numeral 101 denotes a second lens holding barrel that holds the second lens unit 100. The second lens holding barrel 101 engages with the guide bar 95 so as to be movable in the optical axis direction, and similarly engages with the guide bar 97 to prevent rotation about the guide bar 95. .

  Reference numeral 102 denotes a first stepping motor (actuator) that is fixed to the fixed barrel 91 by a screw 126 and moves the first lens unit 98 and the second lens unit 100 in the optical axis direction. Reference numeral 103 denotes a first rack that meshes with a feed screw portion (hereinafter referred to as a first feed screw portion) 102a of the first stepping motor 102 and is driven in the optical axis direction by the rotation of the first feed screw portion 102a.

  Reference numeral 104 denotes a rectilinear drive member (first drive member) that engages with the guide bar 96 so as to be movable in the optical axis direction, and similarly engages with a guide bar (not shown) to center the guide bar 96. Rotation is prevented.

  Reference numeral 105 denotes a first rack spring that urges the first rack 103 in a direction in which the first rack 103 is engaged with the first feed screw portion 102 a and urges (shifts) toward the linear drive member 104 in the image plane direction. Reference numeral 106 denotes a lens barrel driving member (second driving member) that engages with the guide bar 96 so as to be movable in the optical axis direction, and similarly engages with a guide bar (not shown) to center the guide bar 96. Rotation is blocked.

  Reference numeral 107 denotes a first spring (first attachment) that is disposed between the lens barrel driving member 106 and the rectilinear driving member 104 and urges (shifts) the lens barrel driving member 106 toward the rectilinear driving member 104 in the object direction. Force). In the retracted state from the state of FIG. 7, the third abutting portion 106 c of the lens barrel driving member 106 contacts the abutting portion 104 a of the rectilinear drive member 104 by the urging force of the first spring 107. In this state, the lens barrel driving member 106 and the rectilinear driving member 104 move integrally. Then, when the first spring 107 is compressed and deformed, the lens barrel driving member 106 and the rectilinear driving member 104 can move relatively. The length that the lens barrel drive member 106 and the rectilinear drive member 104 can move relative to each other is L9.

  Reference numeral 108 denotes a third spring (between the first lens holding barrel 99 and the fixed barrel 91) that urges (shifts) the first lens holding barrel 99 toward the bar pressing member 92 in the object direction. Third urging means). In the state shown in FIG. 7 and the telephoto state, the first abutting portion 99a of the first lens holding barrel 99 abuts against the abutting portion 92a of the bar pressing member 92 by the urging force of the third spring 108, and the first lens holding portion is held. A cylindrical portion of the lens barrel 99 that holds the first lens unit 98 protrudes from the bar pressing member 92 (that is, the camera body).

  Further, the first lens holding barrel 99 and the barrel driving member 106 can move relative to each other. A length of the first lens holding lens barrel 99 and the lens barrel driving member 106 that is relatively movable is L7. L7 is set to be equal to or longer than the length of movement of the second lens holding barrel 101 for zooming.

  Further, from the telephoto state to the retracted state, the first abutting portion 106a of the lens barrel driving member 106 contacts the second abutting portion 99b of the first lens holding lens barrel 99, and the lens barrel driving member 106 and the first lens holding device are held. The lens barrel 99 moves integrally.

  A second lens 109 is disposed between the bar pressing member 92 and the second lens holding barrel 101, and urges (shifts) the second lens holding barrel 101 toward the barrel driving member 106 in the image plane direction. A spring (second biasing means). In the tele state from the state of FIG. 7, the first abutting portion 101 a of the second lens holding barrel 101 abuts on the second abutting portion 106 b of the barrel driving member 106 by the urging force of the second spring 109, and the second The lens holding barrel 101 and the barrel driving member 106 move integrally in the optical axis direction.

  Assuming that the movable length of the second lens holding barrel 101 is L8, this L8 is set equal to or longer than the length that the second lens holding barrel 101 moves for zooming. L8 is set to be the same as or shorter than L9.

  Reference numeral 110 denotes a fixed third lens unit disposed on the image plane side with respect to the second lens unit 100, and 111 denotes a third lens holding barrel that holds the third lens unit 110. The third lens holding barrel 111 is fixed to the fixed barrel 91.

  Reference numeral 112 denotes an aperture unit fixed to the fixed barrel 91 with a screw 113, and 114 denotes a guide bar that is sandwiched and fixed between the fixed barrel 91 and the third lens holding barrel 111.

  Reference numeral 115 denotes a fourth lens unit which is disposed on the image plane side with respect to the third lens unit 110 and moves in the optical axis direction for image plane movement and focus adjustment accompanying zooming.

  Reference numeral 116 denotes a fourth lens holding barrel that holds the fourth lens unit 115. The fourth lens holding barrel 116 engages with the guide bar 114 so as to be movable in the optical axis direction, and similarly engages with a guide bar (not shown) to prevent rotation about the guide bar 114. Has been.

  Reference numeral 117 denotes a second stepping motor that is fixed to the fixed barrel 91 by screws 118 and moves the fourth lens holding barrel 116 in the optical axis direction. Reference numeral 119 denotes a second rack that meshes with a feed screw portion (hereinafter referred to as a second feed screw portion) 117a of the second stepping motor 117 and moves in the optical axis direction by the rotation of the second feed screw portion 117a. Reference numeral 120 denotes a second rack spring that urges the second rack 119 in a direction in which the second rack 119 is engaged with the second feed screw portion 117 a and urges (shifts) the object toward the fourth lens holding barrel 116.

  Reference numeral 121 denotes a low-pass filter fixed to the fixed barrel 91, and 122 denotes an image sensor pressing plate fixed to the fixed barrel 91 with screws 123. Reference numeral 124 denotes an image pickup element (photoelectric conversion element) such as a CCD or CMOS sensor fixed to the image pickup element holding plate 122, and 125 denotes an elastic member such as rubber sandwiched between the low-pass filter 121 and the image pickup element 124.

  Next, the operation of the lens device will be described. When the first stepping motor 102 is driven from the wide state shown in FIG. 7 to rotate the first feed screw portion 102a in the first direction, the first rack 103 moves in the image plane direction, and the rectilinear drive member 104 and the lens barrel The driving member 106 integrally moves in the image plane direction.

  Here, since the first lens holding barrel 99 is biased in the object direction by the third spring 108 so as to abut against the abutting portion 92a of the bar pressing member 92, the first abutting portion of the lens barrel driving member 106 is used. In the section (first region) of L7, 106a does not come into contact with the second abutting portion 99b of the first lens holding barrel 99 (until the first abutting portion 106a abuts against the second abutting portion 99b). The first lens holding barrel 99 does not move from the state shown in FIG.

  On the other hand, while the first abutting portion 106 a of the lens barrel driving member 106 moves in the image plane direction in the section L 7, the first abutting portion 101 a of the second lens holding lens barrel 101 is the second abutting portion of the lens barrel driving member 106. Since the second lens holding barrel 101 is pressed against the abutting portion 106 b by the urging force of the second spring 109, the second abutting portion 101 b of the second lens holding barrel 101 is an image of the fixed barrel 91. The lens barrel drive member 106 moves in the same direction as the lens barrel drive member 106 moves in the image plane direction in a section L8 until it abuts against the abutting portion 91a formed at the end on the surface side. The state where the second abutting portion 101b of the second lens holding barrel 101 abuts against or abuts against the abutting portion 91a of the fixed barrel 91 is the tele state.

  Further, when the first feed screw portion 102a of the first stepping motor 102 is rotated in the first direction from the telephoto state, the first abutting portion 106a of the lens barrel driving member 106 is moved to the first lens holding lens barrel 99. 2 A section (second region) until the first lens holding barrel 99 is stored inside the fixed barrel 91 and the bar holding member 92 while hitting the abutting portion 99b and pushing it in the image plane direction. The first lens holding barrel 101 is moved in the image plane direction against the urging force of the third spring 108. Thereby, it will be in a retracted state.

  At this time, the second abutting portion 101b of the second lens holding barrel 101 is pressed against the abutting portion 91a of the fixed barrel 91 by the urging force of the second spring 109. The abutting portion 106b moves away from the first abutting portion 101a of the second lens holding barrel 101 in the image plane direction, and the second lens holding barrel 101 does not move.

  Further, when the first stepping motor 102 rotates in the second direction opposite to the first direction from the retracted state, the lens barrel driving member 106 has the second abutting portion 106b of the first lens holding lens barrel 101 in the first direction. It moves in the object direction with the first lens holding member 99 until just before contacting the abutting portion 101a (second region). The first abutting portion 99a of the first lens holding member 99 is in contact with the abutting portion 92a of the bar pressing member 92, and the second abutting portion 106b of the lens barrel driving member 106 is the second lens holding lens barrel 101. After contacting the first abutting portion 101a (first region), the second lens holding barrel 101 is driven in the object direction by the barrel driving member 106.

  Thus, when the lens barrel driving member 106 moves within the section L7 (first region), the lens barrel driving member 106 does not abut on the first lens holding lens barrel 99, and the first lens holding mirror. Although the cylinder 99 is not moved, the lens barrel driving member 106 contacts the second lens holding lens barrel 101 and moves the second lens holding lens barrel 101. On the other hand, when the lens barrel driving member 106 moves in the section (second region) closer to the image plane than the section L7, the lens barrel driving member 106 does not contact the second lens holding lens barrel 101, Although the second lens holding barrel 101 is not moved, the barrel driving member 106 contacts the first lens holding barrel 99 and moves the first lens holding barrel 99.

  When the second stepping motor 117 is driven to rotate the second feed screw portion 117a in the first direction, the second rack 119 moves in the image plane direction, and the fourth lens holding barrel 116 (fourth lens unit). 115) moves in the image plane direction. Further, by rotating the second feed screw portion 117a in the second direction opposite to the first direction, the second rack 119 and the fourth lens holding barrel 116 (fourth lens unit 115) move in the object direction. .

  The lens barrel driving member 106 is moved within the section L7 (and within the section L8) to move the second lens unit 100 in the optical axis direction with the first lens unit 98 fixed, and the fourth lens unit. Zooming can be performed by moving 115 in the optical axis direction. In addition, focus adjustment can be performed by moving the fourth lens unit 115 in the optical axis direction.

  Further, when an external force F3 in the image plane direction is applied to the first lens unit 98 (or the first lens holding barrel 99) in the state of FIG. 7, the first lens unit 98 resists the urging force of the third spring 108. Move in the image plane direction. On the way, the third abutting portion 99c of the first lens holding barrel 99 abuts against the third abutting portion 101c of the second lens holding barrel 101. The lens barrel drive member 106 in contact also moves in the image plane direction together with the first lens holding barrel 99 against the urging force of the first and third springs 107 and 108.

  Here, since L9 has a length equal to or longer than L8, even if the second abutting portion 101b of the second lens holding barrel 101 moves in the image plane direction until it abuts against the abutting portion 91a of the fixed barrel 91, The positions of the rectilinear drive member 104 and the first rack 103 do not change. Accordingly, the first rack 103 and the first feed screw portion 102a are not disengaged.

  When the external force F3 disappears, the first lens holding barrel 99 and the second lens holding barrel 101 return to their original positions (positions shown in FIG. 7) by the urging forces of the first and third springs 107 and 108. be able to.

  In this embodiment, the biasing force by the first spring 107 is set larger than the biasing force of the second spring 109. Accordingly, it is possible to maintain the contact relationship between the rectilinear drive member 104 and the lens barrel drive member 106 shown in FIG.

  In this embodiment, the biasing force in the image plane direction of the second spring 109 is maximized in the wide state, while the biasing force in the object direction of the third spring 108 is maximized in the retracted state. Since the maximum urging force in opposite directions is not generated at a time, the maximum output required for the first stepping motor 102 can be reduced, and the first stepping motor 102 can be reduced in size. Therefore, the lens device can be reduced in size.

  8 to 10 show the configuration of a lens apparatus that is Embodiment 4 of the present invention. This lens apparatus is used for an imaging apparatus such as a digital camera or a video camera. FIG. 8 is a cross-sectional view showing the wide state of the lens apparatus, and FIG. 9 is a cross-sectional view showing the tele state. The state from the state of FIG. 8 to the state of FIG. 9 (including the intermediate state) is hereinafter referred to as a photographing state. 10 is a cross-sectional view showing a retracted state in which the lens apparatus is housed in the camera body (see 10 in FIG. 1), from the state in FIG. 9 to the state in FIG. 10 (including the intermediate state). ) Is called a non-photographing state.

  In these drawings, reference numeral 131 denotes a fixed barrel fixed to the camera body, and 132 denotes a bar pressing member fixed to the fixed barrel 131 by screws 133. The fixed barrel 131 and the bar pressing member 132 constitute the main body of the lens apparatus.

  Reference numerals 134, 135, 136, and 137 denote guide bars that are sandwiched and fixed between the fixed barrel 131 and the bar pressing member 132.

  Reference numeral 138 denotes a first lens unit that is disposed closest to the object side among four lens units described later, is fixed in the optical axis direction in the shooting state, and moves to the image plane side in the non-shooting state. Reference numeral 139 denotes a first lens holding barrel that holds the first lens unit 138. The first lens holding barrel 139 engages with the guide bar 134 so as to be movable in the optical axis direction, and similarly engages with the guide bar 137 to prevent rotation about the guide bar 134. .

  Reference numeral 140 denotes a second lens unit that is arranged on the image plane side with respect to the first lens unit 138 and moves in the optical axis direction to change the magnification. Reference numeral 141 denotes a second lens holding barrel that holds the second lens unit 140. The second lens holding barrel 141 engages with the guide bar 135 so as to be movable in the optical axis direction, and similarly engages with the guide bar 137 to prevent rotation about the guide bar 135. .

  Reference numeral 142 denotes a first stepping motor (actuator) that is fixed to the fixed barrel 131 by a screw 166 and moves the first lens unit 138 and the second lens unit 140 in the optical axis direction. Reference numeral 143 denotes a first rack that meshes with a feed screw portion (hereinafter referred to as a first feed screw portion) 142a of the first stepping motor 142 and is driven in the optical axis direction by the rotation of the first feed screw portion 142a.

  Reference numeral 144 denotes a rectilinear drive member (first drive member) that engages with the guide bar 136 so as to be movable in the optical axis direction, and similarly engages with a guide bar (not shown) to center the guide bar 136. Rotation is prevented.

  Reference numeral 146 denotes a lens barrel driving member (second driving member) which engages with the guide bar 136 so as to be movable in the optical axis direction, and similarly engages with a guide bar (not shown) to center the guide bar 136. Rotation is blocked.

  147 is disposed between the lens barrel drive member 146 and the rectilinear drive member 144, and a first spring (first attachment) that urges (shifts) the lens barrel drive member 146 toward the rectilinear drive member 144 in the object direction. Force). 8 to 10, the third butting portion 146 c of the lens barrel driving member 146 comes into contact with the butting portion 144 a of the rectilinear drive member 144 by the biasing force of the first spring 147. In this state, the lens barrel drive member 146 and the rectilinear drive member 144 move integrally. Then, when the first spring 147 is compressed and deformed, the lens barrel drive member 146 and the rectilinear drive member 144 can move relatively. The length that the lens barrel drive member 146 and the rectilinear drive member 144 can move relative to each other is defined as L12.

  148 is disposed between the first lens holding barrel 139 and the second lens holding barrel 141, and urges (shifts) the first lens holding barrel 139 toward the bar pressing member 132 in the object direction. The second and third combined springs (second and third biasing means) bias the second lens holding barrel 141 toward the barrel driving member 146 in the image plane direction. 8 and 9, the first abutting portion 139a of the first lens holding barrel 139 comes into contact with the abutting portion 132a of the bar pressing member 132 by the biasing force of the second and third combined springs 148. A cylindrical portion of the first lens holding barrel 139 that holds the first lens unit 138 protrudes from the bar pressing member 132 (that is, the camera body).

  Further, the first lens holding barrel 138 and the barrel driving member 146 can move relative to each other. Let L10 be a relatively movable length between the first lens holding barrel 139 and the barrel drive member 146. L10 is set to be equal to or longer than the length that the second lens holding barrel 141 moves for zooming.

  Further, from the state of FIG. 9 to the state of FIG. 10, the first abutting portion 146a of the lens barrel driving member 146 contacts the second abutting portion 139b of the first lens holding lens barrel 139, and the lens barrel driving member 146 and The first lens holding barrel 139 moves integrally.

  8 to 9, the first butting portion 141a of the second lens holding barrel 141 is brought into contact with the second butting portion 146b of the barrel driving member 146 by the biasing force of the second and third combined springs 148. The second lens holding lens barrel 141 and the lens barrel driving member 146 are integrally moved in the optical axis direction.

  Assuming that the movable length of the second lens holding barrel 141 is L11, this L11 is set to be equal to or longer than the length that the second lens holding barrel 141 moves for zooming. L11 is set to be the same as or shorter than L12. L12 is set to be the same as or longer than L10.

  8 and 9, the fourth butting portion 139d provided on the first lens holding barrel 139 has the second butting portion 131b provided on the image plane side end portion of the fixed barrel 131. The length L13 that can be moved until it hits is set to be equal to or longer than L12.

  Reference numeral 150 denotes a fixed third lens unit disposed on the image plane side with respect to the second lens unit 140, and reference numeral 151 denotes a third lens holding barrel that holds the third lens unit 150. The third lens holding barrel 151 is fixed to the fixed barrel 131.

  Reference numeral 152 denotes a diaphragm unit fixed to the fixed barrel 131 with a screw 153, and reference numeral 154 denotes a guide bar fixed between the fixed barrel 131 and the third lens holding barrel 151.

  Reference numeral 1555 denotes a fourth lens unit which is disposed on the image plane side with respect to the third lens unit 150 and moves in the optical axis direction for image plane movement and focus adjustment accompanying zooming.

  Reference numeral 156 denotes a fourth lens holding barrel that holds the fourth lens unit 155. The fourth lens holding barrel 156 engages with the guide bar 154 so as to be movable in the optical axis direction, and similarly engages with a guide bar (not shown) to prevent rotation about the guide bar 154. Has been.

  Reference numeral 157 denotes a second stepping motor which is fixed to the fixed barrel 131 by a screw 158 and moves the fourth lens holding barrel 156 in the optical axis direction. Reference numeral 159 denotes a second rack that meshes with a feed screw portion (hereinafter referred to as a second feed screw portion) 157a of the second stepping motor 157 and moves in the optical axis direction by the rotation of the second feed screw portion 157a. Reference numeral 160 denotes a second rack spring that urges the second rack 159 in a direction in which the second rack 159 is engaged with the second feed screw portion 157 a and urges (shifts) the object toward the fourth lens holding barrel 156.

  Reference numeral 161 denotes a low-pass filter fixed to the fixed barrel 131, and 162 denotes an image sensor pressing plate fixed to the fixed barrel 131 with screws 163. Reference numeral 164 denotes an image pickup element (photoelectric conversion element) such as a CCD or CMOS sensor fixed to the image pickup element holding plate 162, and reference numeral 165 denotes an elastic member such as rubber sandwiched between the low-pass filter 161 and the image pickup element 164.

  Next, the operation of the lens device will be described. When the first stepping motor 142 is driven from the wide state shown in FIG. 8 to rotate the first feed screw portion 142a in the first direction, the first rack 143 moves in the image plane direction, and the rectilinear drive member 144 and the lens barrel The drive member 146 moves integrally in the image plane direction.

  Here, the first lens holding barrel 139 is biased in the object direction by the second and third combined springs 148 so as to abut against the abutting portion 132a of the bar pressing member 132. The first butting portion 146a does not contact the second butting portion 139b of the first lens holding barrel 139 (the first butting portion 146a of the barrel driving member 146 is the second butting portion of the first lens holding barrel 139) The first lens holding barrel 139 does not move from the state of FIG. 8 in the section (first region) of L10 (until just before hitting the portion 139b).

  On the other hand, while the first abutting portion 146a of the lens barrel driving member 146 moves in the image plane direction in the section of L10, the first abutting portion 141a of the second lens holding lens barrel 141 is the second abutting portion of the lens barrel driving member 146. The second lens holding barrel 141 is pressed against the abutting portion 146b by the urging force of the second and third combined springs 148, so that the second abutting portion 141b of the second lens holding barrel 141 is a fixed mirror. The lens barrel drive member 146 moves in the same direction as the lens barrel drive member 146 moves in the image plane direction until it hits the first abutting portion 131a formed at the end of the tube 131 on the image plane side. Then, as shown in FIG. 9, a state in which the second butting portion 141b of the second lens holding barrel 141 abuts on or close to the first abutting portion 131a of the fixed barrel 131 is a tele state.

  Further, when the first feed screw portion 142a of the first stepping motor 142 is rotated in the first direction from the telephoto state shown in FIG. 9, the first abutting portion 146a of the lens barrel driving member 146 becomes the first lens holding mirror. The first lens holding barrel 139 is stored inside the fixed barrel 131 and the bar pressing member 132 as shown in FIG. 10 while hitting the second abutting portion 139b of the barrel 139 and pushing it in the image plane direction. The first lens holding barrel 141 is moved in the image plane direction against the urging force of the second and third combined springs 148 in the interval up to (second region). Thereby, it will be in a retracted state.

  At this time, the second abutting portion 141b of the second lens holding barrel 141 is pressed against the first abutting portion 131a of the fixed barrel 131 by the urging force of the second and third combined springs 148. The second abutting portion 146b of the driving member 146 moves away from the first abutting portion 141a of the second lens holding barrel 141 in the image plane direction, and the second lens holding barrel 141 does not move.

  When the first stepping motor 142 rotates in the second direction opposite to the first direction from the retracted state of FIG. 10, the lens barrel drive member 146 has the second abutting portion 146b as the second lens holding lens barrel 141. It moves in the object direction with the first lens holding member 139 until immediately before it abuts against the first abutting portion 141a (second region). 9, the first abutting portion 139a of the first lens holding member 139 contacts the abutting portion 132a of the bar pressing member 132, and the second abutting portion 146b of the lens barrel driving member 146 is provided. After contacting the first abutting portion 141a of the second lens holding barrel 141 (first region), the second lens holding barrel 141 is driven in the object direction by the barrel driving member 146.

  As described above, when the lens barrel driving member 146 moves within the section L10 (first region), the lens barrel driving member 146 does not contact the first lens holding lens barrel 139, and the first lens holding mirror. Although the barrel 139 is not moved, the barrel drive member 146 contacts the second lens holding barrel 141 and moves the second lens holding barrel 141. On the other hand, when the lens barrel drive member 146 moves within the section (second region) closer to the image plane than the section L10, the lens barrel drive member 146 does not contact the second lens holding lens barrel 141, Although the second lens holding barrel 141 is not moved, the barrel driving member 146 contacts the first lens holding barrel 139 and moves the first lens holding barrel 139.

  When the second stepping motor 157 is driven to rotate the second feed screw portion 157a in the first direction, the second rack 159 moves in the image plane direction, and the fourth lens holding barrel 156 (fourth lens unit) is moved. 155) moves in the image plane direction. Further, by rotating the second feed screw portion 157a in the second direction opposite to the first direction, the second rack 159 and the fourth lens holding barrel 156 (fourth lens unit 155) move in the object direction. .

  The lens barrel driving member 146 is moved in the section L10 (and in the section L11), and the second lens unit 140 is moved in the optical axis direction while the first lens unit 138 is fixed, and the fourth lens unit. Zooming can be performed by moving 155 in the optical axis direction. In addition, focus adjustment can be performed by moving the fourth lens unit 155 in the optical axis direction.

  Furthermore, when an external force F4 in the image plane direction is applied to the first lens unit 138 (or the first lens holding barrel 139) in the state of FIG. 8, the first lens unit 138 biases the second and third combined springs 148. Moves in the image plane direction against On the way, the third abutting portion 139c of the first lens holding barrel 139 abuts against the third abutting portion 141c of the second lens holding barrel 141. The lens barrel drive member 146 in contact also moves in the image plane direction together with the first lens holding barrel 139 against the urging force of the first spring 147.

  Here, since L12 has a length equal to or longer than L11, even if the second abutting portion 141b of the second lens holding lens barrel 141 moves in the image plane direction until it abuts against the abutting portion 131a of the fixed lens barrel 131, The positions of the rectilinear drive member 144 and the first rack 143 do not change. Accordingly, the first rack 143 and the first feed screw portion 142a are not disengaged.

  When the external force F4 disappears, the first lens holding barrel 139 and the second lens holding barrel 141 can return to their original positions (positions shown in FIG. 8) by the biasing force of the first spring 147.

  In this embodiment, the urging force of the first spring 147 is set larger than the urging force of the second and third combined springs 148.

  Further, in this embodiment, since the urging force of the second and third combined springs 148 is maximized in the wide state and the retracted state, the maximum output required for the first stepping motor 142 can be reduced, and the first The stepping motor 142 can be reduced in size. Moreover, the second and third combined springs 148 apply an urging force in the object direction to the first lens holding barrel 139 and an urging force in the image plane direction on the second lens holding barrel 141. The number of parts is reduced compared to the case of using the spring. Therefore, it is possible to reduce the size of the lens device.

  In each of the above-described embodiments, the lengths L3, L6, L9, and L12 that are relatively movable between the rectilinear drive member (first drive member) and the lens barrel drive member (second drive member) are set as the first lens holding mirror. You may set to length L1, L4, L7, L10 or more which can carry out relative movement of a pipe | tube (1st holding member) and a lens-barrel drive member.

  Further, the lengths L1, L4, L7, and L10 in which the first lens holding barrel and the second driving member are relatively movable are set to be longer than the movable length of the first holding member with respect to the apparatus main body. Also good.

In addition, the length of relative movement between the second lens holding barrel and the barrel driving member may be set to be longer than the movable length of the second lens holding barrel with respect to the apparatus main body.
In each of the above-described embodiments, the case where the coil spring is used as the biasing means has been described. However, other means such as a plate spring other than the coil spring, or magnetic biasing may be used.

  In each of the above-described embodiments, the case where the stepping motor is used as the actuator has been described. However, other actuators such as a vibration type actuator and a moving coil may be used.

It is sectional drawing which shows the structure (wide state) of the lens apparatus which is Example 1 of this invention. FIG. 3 is a cross-sectional view illustrating a configuration (telephoto state) of the lens device of Example 1. FIG. 3 is a cross-sectional view illustrating a configuration (collapsed state) of the lens device according to the first embodiment. FIG. 3 is a cross-sectional view illustrating a configuration of the lens device according to the first exemplary embodiment (a state where an external force is applied). It is sectional drawing which shows the structure (wide state) of the lens apparatus which is Example 2 of this invention. 6 is a cross-sectional view illustrating a configuration (collapsed state) of a lens device according to Example 2. FIG. It is sectional drawing which shows the structure of the lens apparatus (wide state) which is Example 3 of this invention. It is sectional drawing which shows the structure (wide state) of the lens apparatus which is Example 4 of this invention. 10 is a cross-sectional view illustrating a configuration (telephoto state) of a lens device according to Example 4. FIG. 6 is a cross-sectional view illustrating a configuration (collapsed state) of a lens device according to Example 4. FIG. It is sectional drawing which shows the structure of the conventional lens apparatus.

Explanation of symbols

11, 51, 91, 131 Fixed barrel 12, 52, 92, 132 Bar pressing member 14, 15, 16, 17, 54, 55, 56, 57, 94, 95, 96, 97, 134, 135, 136, 137 Guide bar 18, 58, 98, 138 First lens unit 19, 59, 99, 139 First lens holding barrel 20, 60, 100, 140 Second lens unit 21, 61, 101, 141 Second lens holding mirror Tubes 22, 62, 102, 142 First stepping motors 23, 63, 103, 143 First racks 24, 64, 104, 144 Straight drive units 25, 65, 105 First rack springs 26, 66, 106, 146 Drive members 27, 67, 107, 147 First springs 28, 68, 108 Third springs 29, 69, 109 Second springs 30, 70, 110, 150 Third lens unit 31, 71, 111, 151 Third lens holding barrel 32, 72, 112, 152 Aperture unit 34, 74, 114, 154 Guide bar 35, 75, 115, 155 Fourth lens unit 36, 76, 116, 156 Fourth lens holding barrels 37, 77, 117, 157 Second stepping motors 39, 79, 119, 159 Second racks 40, 80, 120, 160 Second rack springs 41, 81, 121, 161 Low pass filter 44, 84, 124, 164 Image sensor 148 Second and third combined spring

Claims (10)

An actuator,
A first drive member driven in the optical axis direction by the actuator;
A first holding member that holds the first lens unit and is movable in the optical axis direction;
A second holding member that holds the second lens unit disposed closer to the image plane than the first lens unit and is movable in the optical axis direction;
A second driving member capable of contacting the first and second holding members in the optical axis direction and moving in the optical axis direction upon receiving a driving force from the first driving member;
First biasing means for biasing the second driving member toward the first driving member in the object direction;
Second urging means for urging the second holding member toward the second driving member in the image plane direction;
A third urging means for urging the first holding member toward the apparatus main body in the object direction;
When the second driving member is located in the first region in the optical axis direction, the second driving member is not in contact with the first holding member and is in contact with the second holding member. An optical device, wherein the optical device is not in contact with the second holding member and is in contact with the first holding member when positioned in the second region closer to the image plane. When the second driving member is located in the first region, the first holding member abuts on the apparatus main body by the urging force of the third urging means,
The second holding member abuts on the apparatus main body by a biasing force of the second biasing means when the second driving member is located in the second region. 2. The optical device according to 1. When the second driving member is located in the first region, the first holding member abuts against a contact portion of the apparatus main body and protrudes from the apparatus main body toward the object side,
3. The optical device according to claim 1, wherein when the second driving member is located in the second region, the first holding member is separated from the contact portion toward the image plane side. apparatus.   4. The optical apparatus according to claim 1, wherein the second urging unit and the third urging unit are combined with a single urging unit. A plurality of lens units including the first and second lens units;
5. The optical apparatus according to claim 1, wherein the first lens unit is disposed closest to the object side among the plurality of lens units. 6.   6. The optical apparatus according to claim 1, wherein a biasing force of the first biasing unit is stronger than a biasing force of the third biasing unit.   6. The optical apparatus according to claim 1, wherein a biasing force of the first biasing unit is stronger than a biasing force of the second biasing unit.   2. The biasing force of the first biasing means is stronger than the biasing force obtained by combining the biasing force of the second biasing means and the biasing force of the third biasing means. The optical device according to any one of 1 to 5.   6. The length of the first drive member and the second drive member that are relatively movable is equal to or greater than the movable length of the second holding member. 6. The optical apparatus as described in any one. An optical device according to any one of claims 1 to 9,
An optical apparatus comprising a photoelectric conversion element that photoelectrically converts an object image formed by the lens unit.

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