Patent Publication Number: US-2022229265-A1

Title: Lens apparatus, image capturing apparatus, and image capturing system

Description:
BACKGROUND OF THE DISCLOSURE 
     Field of the Disclosure 
     The aspect of the embodiments relates to a lens apparatus, an image capturing apparatus, and an image capturing system. 
     Description of the Related Art 
     Some lens apparatuses that drive a lens in the optical axis direction by using an actuator such as a motor have a lens drive assist configuration in which the lens can be driven with respect to the base member that can be driven in the optical axis direction by a user&#39;s rotation operation of the cam ring. This lens drive assist configuration makes it possible to drive the lens by the total drive amount of a drive amount of the base member (base drive amount) and a drive amount of the lens (motor drive amount) with respect to the base member. 
     Japanese Patent Application Laid-Open No. 2014-16513 discusses a technique of controlling a motor using electronic cam data to move the focus lens to correct focus variations with movement of a variable power lens. 
     The electronic cam data is data indicating positions of the focus lens (in-focus position) where the variable power lens (zoom position) is in focus at individual subject distances. 
     However, as in the electronic cam data discussed in Japanese Patent Application Laid-Open No. 2014-16513, in general, the difference is large between the in-focus position at infinity at the wide-angle end of the zoom position and the in-focus position at a close distance at the telephoto end. When the focus lens is driven by the above-described lens drive assist configuration according to such electronic cam data, the base drive amount (cam lift) between the wide-angle end and the telephoto end is constant regardless of subject distances, for which a larger motor drive amount for the focus lens is more suitable, which will lead to a larger lens apparatus. 
     SUMMARY OF THE DISCLOSURE 
     According to an aspect of the embodiments, a lens apparatus includes a first lens unit configured to move in an optical axis direction in zooming, a second lens unit configured to move in the optical axis direction in zooming and focusing, a second lens barrel configured to hold the second lens unit, a first lens barrel configured to hold the first lens unit and a guide bar, the guide bar being configured to hold the second lens barrel movably in the optical axis direction, a drive unit configured to drive the second lens barrel in the optical axis direction in focusing, a connection member configured to connect the second lens barrel and the drive unit, a first urging member configured to urge the connection member against the drive unit and urge the second lens barrel against the guide bar, a movement base configured to hold the drive unit and move the drive unit in the optical axis direction with respect to the first lens barrel, and a second urging member configured to urge the movement base in a direction orthogonal to a plane passing through a first support portion, a second support portion, and a third support portion, the first support portion, the second support portion, and the third support portion being configured to support the movement base in a direction orthogonal to the optical axis on the first lens barrel. The connection member moves in a direction intersecting with a line connecting the first support portion and the second support portion as viewed in the direction orthogonal to the plane passing through the first support portion, the second support portion, and the third support portion. A moment by an urging force of the second urging member about an axis connecting the first support portion and the second support portion is greater than a moment by an urging force of the first urging member about the axis connecting the first support portion and the second support portion. 
     Further features of the disclosure will become apparent from the following description of exemplary embodiments with reference to the attached drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a sectional view illustrating a configuration of an interchangeable lens at the wide-angle end according to an exemplary embodiment of the disclosure. 
         FIG. 2  is a sectional view illustrating a configuration of the interchangeable lens at the telephoto end according to the exemplary embodiment. 
         FIGS. 3A and 3B  are perspective views each illustrating a rear unit according to the exemplary embodiment. 
         FIG. 4  is an exploded perspective view illustrating the rear unit in the interchangeable lens according to the exemplary embodiment. 
         FIG. 5  is an exploded perspective view illustrating the rear unit in the interchangeable lens according to the exemplary embodiment. 
         FIGS. 6A and 6B  are sectional views each illustrating a configuration of the rear unit at the wide-angle end according to the exemplary embodiment. 
         FIGS. 7A and 7B  are sectional views each illustrating a configuration of the rear unit at the telephoto end according to the exemplary embodiment. 
         FIG. 8  is a graph illustrating in-focus positions of a sixth lens according to the exemplary embodiment. 
         FIG. 9  is a graph illustrating in-focus positions of the sixth lens with respect to a seventh unit according to the exemplary embodiment. 
         FIG. 10  is a graph illustrating positions of the rear unit and the seventh unit and the difference between the positions according to the exemplary embodiment. 
         FIGS. 11A and 11B  are top views each illustrating the rear unit and a motor movement base according to the exemplary embodiment. 
         FIGS. 12A and 12B  are schematic diagrams each illustrating a relationship between action positions of forces in a focus assist configuration according to the exemplary embodiment. 
         FIG. 13  is a perspective view illustrating a lens apparatus and an image capturing apparatus according to an exemplary embodiment of the disclosure. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     Some exemplary embodiments of the disclosure will be described in detail below with reference to the accompanying drawings. Like numbers refer to like members throughout the drawings, and redundant descriptions will be omitted. 
       FIGS. 1 and 2  each illustrate a configuration of an interchangeable lens  1  as a lens apparatus according to an exemplary embodiment of the disclosure.  FIG. 1  is a sectional view of the interchangeable lens  1  at the wide-angle end taken along a line parallel to the optical axis.  FIG. 2  is a sectional view of the interchangeable lens  1  at the telephoto end taken along a line parallel to the optical axis.  FIG. 3  is a perspective view of a rear unit  80 .  FIGS. 4 and 5  are exploded perspective views each illustrating the rear unit  80  in the interchangeable lens  1  according to the exemplary embodiment of the disclosure. 
     (Configuration of Interchangeable Lens) 
     The interchangeable lens  1  is detachably mounted on a camera body serving as an image capturing apparatus (not illustrated) including an image sensor such as a charge-coupled device (CCD) sensor or a complementary metal-oxide semiconductor (CMOS) sensor. The interchangeable lens  1  includes an image capturing optical system composed of a first lens unit L 1 , a second lens unit L 2 , a third lens unit L 3 , a fourth lens unit L 4 , a fifth lens unit L 5 , a sixth lens unit L 6 , and a seventh lens unit L 7 , which are arranged in order from nearer the subject (front side). The image capturing optical system focuses light from a subject (not illustrated) on the image sensor in the camera body to thereby form a subject image. A floating lens unit as the fourth lens unit L 4  and a focus lens unit as the sixth lens unit L 6  move in the optical axis direction to perform focusing. The first to seventh lens units L 1  to L 7  move in the optical axis direction to perform zooming. The present exemplary embodiment illustrates the interchangeable lens  1  as an example of the lens apparatus. In some embodiments, the lens apparatus is a lens-integrated image capturing apparatus. 
     A first unit  10  is composed of the first lens unit L 1 , a first unit lens barrel  11 , a first unit barrel  106 , and a filter frame  107 . The first unit lens barrel  11  holds the first lens unit L 1 . The first unit lens barrel  11  is fixed to the first unit barrel  106 . The filter frame  107  is fixed to the first unit barrel  106 . The first unit  10  has a configuration in which rollers (not illustrated) placed in the first unit barrel  106  engage with cam grooves formed in a cam ring  105  and with straight grooves formed in a guide barrel  104 , and moves in the optical axis direction rotating about the optical axis of the cam ring  105 . 
     A second unit lens barrel  21  holds the second lens unit L 2 . The second unit lens barrel  21  constitutes a part of an image stabilization unit  20 . The image stabilization unit  20  holds the second unit lens barrel  21  movably in the direction orthogonal to the optical axis, and drives the second lens unit L 2  using an actuator composed of a magnet and a coil to thereby correct image shake. The image stabilization unit  20  is fixed to the guide barrel  104  via rollers (not illustrated) placed in the image stabilization unit  20 . 
     A third unit  30  is composed of the third lens unit L 3 , a third unit lens barrel  31 , and a diaphragm unit  34 . The third unit lens barrel  31  holds the third lens unit L 3 . The diaphragm unit  34  is a diaphragm unit to adjust the quantity of light, and is fixed to the third unit lens barrel  31 . The third unit  30  is fixed to a rear unit base  81  via third unit rollers  32 . The third unit rollers  32  are fixed to the third unit lens barrel  31  with third unit roller fastening screws  33 . 
     A fourth unit  40  is composed of the fourth lens unit L 4 , a fourth unit lens barrel  41 , a rack  42 , and a rack spring  43 . The fourth unit lens barrel  41  holds the fourth lens unit L 4 . The fourth unit  40  is linearly guided by guide bars  92  sandwiched between the rear unit base  81  and guide bar covers  93 . The movement of the rear unit base  81  (first lens barrel) in the optical axis direction in zooming moves the fourth lens unit L 4  in the optical axis direction. Further, the fourth lens unit L 4  is driven by a fourth lens drive motor unit  96  in the optical axis direction to move with respect to the rear unit base  81 . The rack  42  is urged in a direction orthogonal to the optical axis by the rack spring  43  to fit into the fourth lens drive motor unit  96 . The rack  42  is also urged against the fourth unit lens barrel  41  in the optical axis direction by the rack spring  43 . The fourth unit lens barrel  41  is urged against the guide bars  92  by the urging force of the rack spring  43  in a direction orthogonal to the optical axis. The fourth unit lens barrel  41  includes a scale (not illustrated) for detecting its position in the optical axis direction. An optical sensor for detecting the fourth lens position (not illustrated) opposed to the scale is fixed to the rear unit base  81  through a flexible printed circuit board. The scale and the optical sensor detect the position of the fourth unit lens barrel  41  relative to the rear unit base  81 . 
     A fifth unit  50  is composed of the fifth lens unit L 5  and a fifth unit lens barrel  51 . The fifth unit lens barrel  51  holds the fifth lens unit L 5 . The fifth unit  50  is fixed to the rear unit base  81  via fifth unit rollers  52 . The fifth unit rollers  52  are fixed with fifth unit roller fastening screws  53 . 
     A sixth unit  60  is composed of the sixth lens unit L 6 , a sixth unit lens barrel  61 , a rack  62  (connection member), and a rack spring  63  (first urging member). The sixth unit lens barrel  61  (second lens barrel) holds the sixth lens unit L 6  (second lens unit). The sixth unit lens barrel  61  is linearly guided by the guide bars  92  sandwiched between the rear unit base  81  and the guide bar covers  93 . The movement of the rear unit base  81  in the optical axis direction in zooming moves the sixth lens unit L 6  in the optical axis direction. Further, the sixth lens unit L 6  is driven by a sixth lens drive motor unit  95  (drive unit) to move in the optical axis direction. The rack  62  is urged in a direction orthogonal to the optical axis by the rack spring  63  to fit into the sixth lens drive motor unit  95 . The rack  62  is also urged against the sixth unit lens barrel  61  in the optical axis direction by the rack spring  63 . The sixth unit lens barrel  61  includes a scale (not illustrated) for detecting its position in the optical axis direction. An optical sensor for detecting the sixth lens position (not illustrated) opposed to the scale is fixed to the rear unit base  81  through a flexible printed circuit board. The scale and the optical sensor detect the position of the sixth unit lens barrel  61  relative to the rear unit base  81 . 
     The rear unit  80  holds the third unit  30 , the fourth unit  40 , the fifth unit  50 , and the sixth unit  60  as described above. The fourth lens drive motor unit  96  is fixed to the rear unit  80  with motor unit fastening screws  91 . The sixth lens drive motor unit  95  is fixed to a motor movement base  85  with motor unit fastening screws  87 . A motor movement base urging member  84  (second urging member) is disposed between the rear unit base  81  and the motor movement base  85 , and the motor movement base urging member  84  and the movement base  85  are sandwiched between the rear unit base  81  and a motor movement base separation stopping screw  86 . Rear unit rollers  82  are fixed to the rear unit base  81  with rear unit roller fastening screws  83 . The rear unit  80  has a configuration in which the rear unit rollers  82  engage with the cam grooves formed in the cam ring  105  and with the straight grooves formed in the guide barrel  104  and integrally moves in the optical axis direction rotating about the optical axis of the cam ring  105 . 
     The motor movement base  85  is fixed with a seventh unit connection screw  88 . A motor movement base urging member  89  is fixed with a motor movement base urging member fastening screw  90 . The motor movement base  85  includes protrusions (not illustrated) to engage with a straight groove  812  and a straight groove  813  formed in the rear unit base  81 . The motor movement base  85  is guided along the straight groove  812  and the straight groove  813  to move in the optical axis direction with respect to the rear unit  80 . 
     A seventh unit  70  is composed of the seventh lens unit L 7  and a seventh unit lens barrel  71 . The seventh unit lens barrel  71  (third lens barrel) holds the seventh lens unit L 7  (third lens unit). Seventh unit rollers  72  are fixed to the seventh unit lens barrel  71  with seventh unit roller fastening screws  73 . The seventh unit  70  has a configuration in which the seventh unit rollers  72  engage with the cam grooves formed in the cam ring  105  and with the straight grooves formed in the guide barrel  104  and integrally moves in the optical axis direction rotating about the optical axis of the cam ring  105 . The seventh unit connection screw  88  fixed to the motor movement base  85  is fit in a long hole  710  formed in the seventh unit lens barrel  71 . The seventh unit connection screw  88  fitted in the long hole  710  allows the motor movement base  85  and the sixth lens drive motor unit  95  to move in the optical axis direction integrally with the seventh unit  70 . 
     The fourth lens drive motor unit  96  and the sixth lens drive motor unit  95  use vibration-type linear motors with piezoelectric elements. Each vibration-type linear motor includes a motor stator, a motor mover to move in the optical direction with respect to the motor stator by vibration excited by the motor stator and the piezoelectric element, and a motor output portion to move in the optical axis direction together with the motor mover. Thus, each motor unit according to the present exemplary embodiment can drive an optical element such as a lens with an actuator. 
     A lens mount  101  includes a bayonet portion used for detachably mounting the lens mount  101  on the camera body, and is fixed to a fixing barrel  102 . An exterior barrel  103  is fixed to the fixing barrel  102 . A zoom index and operation switches (not illustrated) are provided on the exterior barrel  103 . 
     The guide barrel  104  is provided with a plurality of straight grooves extending in the optical axis direction. The cam ring  105  is rotatably fit to the outer surface of the guide barrel  104 . The fixing barrel  102  fixes the guide barrel  104 . An integrated circuit (IC) for driving the interchangeable lens  1 , a microcomputer, and other devices are mounted on a printed circuit board  108 . The printed circuit board  108  is fixed to the fixing barrel  102 . A manual focus ring  109  is sandwiched between the front ring  110  and the fixing barrel  102 , and is supported rotatably about the axis of the fixing barrel  102 . When the manual focus ring  109  is rotated, the rotation is detected by a sensor (not illustrated) and in-focus control is performed based on the amount of rotation. A mount ring  112  is fixed by being sandwiched between the lens mount  101  and the fixing barrel  102 . A mount rubber  113  is sandwiched between the inner surface of the mount ring  112  and the lens mount  101 . A back lid  114  is fixed to the lens mount  101 . A contact block  115  (contact portion) is electrically connected to the printed circuit board  108  with wiring (a flexible printed circuit board or the like) (not illustrated) and is fixed to the lens mount  101 . 
     With the interchangeable lens  1  fixed to the camera body, the printed circuit board  108  for controlling the operation of each lens can communicate with the camera body through the contact block  115 . The interchangeable lens  1  focuses light from a subject on the image sensor in the camera body, and converts the light into an electric signal, thereby creating a recorded image. 
     A zoom ring  111  is sandwiched between the fixing barrel  102  and the exterior barrel  103  and is supported rotatably about the axis of the fixing barrel  102 . The zoom ring  111  is connected to the cam ring  105  via a key (not illustrated). The rotation operation of the zoom ring  111  rotates the cam ring  105 , allowing the lens barrels described above to move in the optical axis direction. Varying intervals between the barrels enable images to be captured with focal lengths in the range from the wide-angle end to the telephoto end. The amount of rotation of the zoom ring  111  is detected by a sensor (not illustrated) and the signal is determined by the IC on the printed circuit board  108 , which allows a focus control, an image-shake correction control, and a diaphragm drive control based on each focal length. The IC on the printed circuit board  108  controls the movements of the fourth lens unit L 4  and the sixth lens unit L 6  so that varying focus positions and various aberration amounts in zooming will be kept at certain values or less. 
     (Focus Lens Unit Drive Control) 
     Next, a drive control to be performed in zooming of the sixth lens unit L 6  serving as the focus lens unit and data used in the drive control will be described. The following is a description of the sixth lens unit L 6  and the sixth lens drive motor unit  95  for driving the sixth lens unit L 6 . In addition, the fourth lens unit L 4  and the fourth lens drive motor unit  96  for driving the fourth lens unit L 4  are similar to those. 
       FIGS. 6A and 6B  are sectional views each illustrating a state where the rear unit  80  and the seventh unit  70  are located at the wide-angle end.  FIGS. 7A and 7B  are sectional views each illustrating a state where the rear unit  80  and the seventh unit  70  are located at the telephoto end.  FIGS. 6A and 7A  each illustrate an in-focus state at infinity.  FIGS. 6B and 7B  each illustrate an in-focus state at the closest distance.  FIGS. 6A and 6B  and  FIGS. 7A and 7B  each illustrate a sectional view taken along a line parallel to the optical axis. 
       FIG. 8  is a graph illustrating in-focus positions of the sixth lens unit L 6  (hereinafter referred to as a sixth lens in-focus position) with respect to focal lengths (zoom position). An optical sensor for detecting sixth lens positions (not illustrated) is fixed to the rear unit base  81 . The optical sensor for detecting sixth lens positions and the rear unit  80  move in the optical axis direction with respect to the lens mount  101  in zooming. Thus,  FIG. 8  shows sixth lens in-focus positions (with respect to the position detecting sensor or the rear unit) detected by the optical sensor for detecting sixth lens positions, which are not sixth lens in-focus positions with respect to the lens mount  101 . 
     In  FIG. 8 , the horizontal axis represents focal lengths (zoom position) drawn continuously in the range from the wide-angle end to the telephoto end. The vertical axis represents sixth lens in-focus positions with respect to the reference in-focus position ( 0 ) at infinity at the wide-angle end. The sixth lens in-focus positions on the imaging plane side are referred to as positive, and on the subject side are referred to as negative. The solid line represents sixth lens in-focus positions at infinity, and the broken line represents sixth lens in-focus positions at the closest distance. The lines of the sixth lens in-focus positions are equivalent to positional information detected by the optical sensor for detecting sixth lens positions (not illustrated), and are positional information used in feedback control of the sixth lens drive motor unit  95 . 
       FIG. 9  is a graph illustrating sixth lens in-focus positions with respect to zoom positions, as in  FIG. 8 . However,  FIG. 9  illustrates sixth lens in-focus positions with respect to the seventh unit  70 . The seventh unit  70 , the rear unit base  81 , and the sixth lens drive motor unit  95  integrally move in the optical axis direction. Thus,  FIG. 9  also shows sixth lens in-focus positions with respect to the rear unit base  81  or the sixth lens drive motor unit  95 . The horizontal axis, the vertical axis, the positive side, the negative side, the solid line, and the broken line illustrated in  FIG. 9  are defined the same as those in  FIG. 8 . 
       FIG. 10  is a graph illustrating positions (dashed-dotted line) of the rear unit  80  and positions (dotted line) of the seventh unit  70  with respect to zoom positions. The differences between the positions of the rear unit  80  and the seventh unit  70  is represented by the solid line. The horizontal axis represents zoom positions drawn continuously in the range from the wide-angle end to the telephoto end. The vertical axis represents positions of the rear unit  80  and the seventh unit  70  with respect to the reference in-focus position ( 0 ) at infinity at the wide-angle end. 
     The differences between positions of the rear unit  80  and the seventh unit  70  as represented by the solid line in  FIG. 10  are varying amounts in positions of the sixth unit detected by the optical sensor for detecting sixth lens positions (not illustrated) with the sixth lens drive motor unit  95  not driven in zooming. Thus, the configuration of assisting the movement of the sixth lens drive motor unit  95  (or the sixth lens unit L 6 ) by the seventh unit  70  is defined as a focus assist configuration. In other words, the solid line illustrated in  FIG. 10  represents the amounts of focus assist performed by the seventh unit  70  with respect to the rear unit  80 . Data obtained by subtracting the focus assist amount illustrated in  FIG. 10  from the sixth lens in-focus position with respect to the rear unit  80  illustrated in  FIG. 8  corresponds to data illustrated in  FIG. 9 . Electronic cam data (i.e., data obtained based on the focus assist amount) indicating the sixth lens in-focus positions with respect to the sixth lens drive motor unit  95  illustrated in  FIG. 9  is stored in a lens control unit of the printed circuit board  108 . The lens control unit controls the driving of the sixth lens drive motor unit  95  using the stored electronic cam data in zooming. 
     (Beneficial Effects of Focus Assist) 
     A range “A” illustrated in  FIG. 8  is a range for movement of the sixth lens unit L 6 . A range “B” illustrated in  FIG. 9  is a range for driving the sixth lens unit L 6  by the sixth lens drive motor unit  95 . The focus assist configuration provides the relationship of range “A”&gt;range “B”, reducing the motor drive amount. That allows the sixth lens drive motor unit  95  to be shortened in the optical axis direction, which contributes to a smaller size of the interchangeable lens  1 . In other words, the movable range of the sixth lens unit L 6  is extendable with a reduced motor drive amount. 
     The slope formed by a zoom range C and a position variation E illustrated in  FIG. 9  (i.e., position variation E/zoom range C) is less than the slope formed by the zoom range C and a position variation D (i.e., position variation D/zoom range C) illustrated in  FIG. 8 . That allows a lower driving speed of the sixth lens drive motor unit  95 . In other words, that reduces the driving speed of the sixth lens unit L 6 , which leads to a higher focus followability in zooming. 
     (Relationship between Actions of Forces in Focus Assist Configuration) 
     Next, a relationship between actions of forces related to the focus assist configuration according to the exemplary embodiment will be described. 
       FIGS. 11A and 11B  each illustrate the rear unit  80  and the motor movement base  85 .  FIGS. 11A and 11B  also illustrate a positional relationship in the focus assist configuration.  FIG. 11A  is a top view of the rear unit  80 .  FIG. 11B  is a top view of the rear unit  80  and the seventh unit  70 . The components not used in the following description are omitted in  FIGS. 11A and 11B . 
       FIGS. 12A and 12B  are schematic diagrams each illustrating a positional relationship between actions of forces in the focus assist configuration.  FIG. 12A  illustrates a state where an urging force is not generated by the motor movement base urging member  84 , and  FIG. 12B  illustrates a state where an urging force is generated by the motor movement base urging member  84 . 
     As described above, the motor movement base urging member  84  and the motor movement base  85  are sandwiched between the rear unit base  81  and the motor movement base separation stopping screw  86 . As illustrated in  FIG. 11A , the motor movement base urging member  84  includes an urging portion  840  and an urging portion  841  for urging the motor movement base  85  at a point K and a point L, respectively. 
     As illustrated in  FIGS. 4 and 5 , the motor movement base  85  includes a separation prevention portion  850 , a separation prevention portion  851 , and a separation prevention portion  852 . The separation prevention portion  850  is urged by the rack spring  63  and the motor movement base urging member  84 , which bring the separation prevention portion  850  into contact with the motor movement base separation stopping screw  86 , which is fixed to the rear unit base  81 . The separation prevention portion  851  and the separation prevention portion  852  form a hook shape and are provided on the rear unit base  81 . The separation prevention portions  851  and  852  are inserted into a separation prevention hole  810  and a separation prevention hole  811 , respectively. Thus, the configuration of each separation prevention portion formed on the motor movement base  85  inserted into the corresponding separation prevention hole serving as an opening formed in the rear unit base  81  allows the motor movement base  85  to be supported on the rear unit base  81 . Further, in this configuration, the separation prevention portion  851  and the separation prevention portion  852  are in contact with the separation prevention hole  810  and the separation prevention hole  811  by urging forces received from the rack spring  63  and the motor movement base urging member  84 . These separation prevention portions each function as a support portion that radially supports the motor movement base  85  on the rear unit base  81 . Specifically, the motor movement base  85 , which holds the sixth lens drive motor unit  95 , is held on the plane defined by three portions: the separation prevention portion  850  (first support portion), the separation prevention portion  851  (third support portion), and the separation prevention portion  852  (second support portion). 
     In the present exemplary embodiment, the position of the separation prevention portion  850  is defined as a point H, the position of the separation prevention portion  851  is defined as a point F, and the position of the separation prevention portion  852  is defined as a point G. As positions where the sixth lens drive motor unit  95  receives an urging force from the rack spring  63  (positions where the rack  62  engages with the sixth lens drive motor unit  95 ), an in-focus position at infinity is defined as a point I and an in-focus position at the closest distance is defined as a point J. 
     As illustrated in  FIGS. 11B and 12A , in the present exemplary embodiment, an urging force P received by the motor movement base  85  from the rack spring  63  moves between the point I and the point J across the G-H axis connecting the point G and the point H. Thus, the rack  62  serving as the connection member moves in a direction intersecting with the line connecting the first support portion and the second support portion as viewed in a direction orthogonal to the plane passing through the first support portion, the second support portion, and the third support portion. In this case, positive and negative values of the moment about the G-H axis are reversed before and after the urging force P moves across the G-H axis during movement between the point I and the point J. In other words, the moment about the G-H axis in the vicinity of the G-H axis is small, making the urging force against the motor movement base  85  unstable. 
     As a result, drive of the sixth lens drive motor unit  95  held on the motor movement base  85  in feedback control can cause vibration due to variable positions detected by the optical sensor for detecting sixth lens positions. Vibration makes it difficult to detect positions of the sixth lens unit L 6  with high accuracy. In addition, noise from vibration impairs quality. To reduce vibration, keeping the moment about any axis, namely, the F-H axis, the F-G axis, or the G-H axis, in one direction constantly is effective. 
     With no urging force generated by the motor movement base urging member  84  as illustrated in  FIG. 12A , the path between the point I and the point J should be inside the triangle formed by the point F, the point G, and the point H. That layout will cause a larger triangle formed by the point F, the point G, and the point H, leading to a longer overall length and a longer outer diameter of the interchangeable lens  1 . Alternatively, the path between the point I and the point J should be outside the triangle formed by the point F, the point G, and the point H. That layout will cause a longer overall length of the interchangeable lens  1  due to an extended size in the optical axis. 
     In the present exemplary embodiment, as illustrated in  FIGS. 11A and 11B  and  FIG. 12B , an urging force Q generated by the motor movement base urging member  84  acts on the point K. The position of the point K and the magnitude of the urging force Q are determined so that the moment by the action of the urging force Q on the point K will be greater than that by the action of the urging force P on the point I about the F-H axis. The distance from the line between the point G and the point H up to the point K is longer than either the distance from the point I to the line or the distance from the point J to the line. That means that the moment about the G-H axis points to the same direction constantly, making the urging condition against the motor movement base  85  stable. That configuration allows the triangle formed by the point F, the point G, and the point H and the path between the point I and the point J to be disposed in an overlapped manner, which leads to a reduction in the overall length and outer diameter of the interchangeable lens  1 . Furthermore, that reduces vibration during the drive of the sixth lens drive motor unit  95  held on the motor movement base  85  in feedback control. 
     As described above, the motor movement base  85  is movable in the optical axis direction, being guided along the straight groove  812  and the straight groove  813  with respect to the rear unit base  81 . The motor movement base urging member  84  urges the motor movement base  85  against the straight groove  812  and the straight groove  813 . Urging the motor movement base  85  against the straight groove  812  and the straight groove  813  involves the action of force in a direction orthogonal to the groove direction. In terms of urging against the straight groove  812  and the straight groove  813 , it is suitable that the urging force acts on an intermediate point between the straight groove  812  and the straight groove  813  in the optical axis direction. However, the movement range of the sixth unit lens barrel  61  and the motor movement base separation stopping screw  86  will be arranged at intermediate points between the straight groove  812  and the straight groove  813 . 
     In the present exemplary embodiment, the motor movement base urging member  84  urges the motor movement base  85  at the point L and the point K in directions orthogonal to the groove direction of the straight groove  812  and the straight groove  813 . At the point L, the motor movement base  85  is urged against the rear unit base  81  in a direction on the plane passing through the point F, the point G, and the point H. At the point L, the motor movement base  85  is also urged in a direction orthogonal to the groove direction of the straight groove  812  and the straight groove  813 . At the point K, the motor movement base  85  is urged in a direction orthogonal to the groove direction of the straight groove  812  and the straight groove  813 , and is also urged (urging force Q) in a direction substantially orthogonal to the plane passing through the point F, the point G, and the point H. The direction of the urging force generated at the point K corresponds to the direction in which the urging forces are combined. That configuration makes it possible to stably urge the motor movement base  85 , without increasing the number of components. This results in contributing to a reduction in the overall length and outer diameter of the interchangeable lens  1 . 
     In the present exemplary embodiment, the seventh unit connection screw  88  is fit in the long hole  710 , allowing the motor movement base  85  and the sixth lens drive motor unit  95  to move in the optical axis direction integrally with the seventh unit  70 . The cylindrical head portion of the seventh unit connection screw  88  is in line contact with the long hole  710 . The area where the long hole  710  and the seventh unit connection screw  88  serving as a fixing member are in line contact with each other at least partially overlaps the sixth lens drive motor unit  95  serving as the drive unit as viewed in the optical axis direction. That configuration allows the force transmitted to the motor movement base  85  by the movement of the seventh unit  70  in zooming to be limited in the optical axis direction. The motor movement base  85  is movable in the optical axis direction with respect to the rear unit base  81  alone. Movement of the motor movement base  85  in a direction other than the optical axis direction will involve urging the motor movement base  85  more stably by the rack spring  63  and the motor movement base urging member  84 . 
     On the other hand, a force transmitted to the motor movement base  85  in a direction other than the optical direction by movement of the seventh unit  70  in zooming would be counteracted by a larger force as the urging force generated by the rack spring  63  and/or the motor movement base urging member  84 , leading to an increase in the size of units, resulting in an increase in the size of the interchangeable lens  1 . Further, a configuration of connecting the motor movement base  85  and the seventh unit  70 , such as a bayonet, would entail the forms of the seventh unit  70  and the rear unit  80  such that they will avoid contact each other in connection between the motor movement base  85  and the seventh unit  70 , leading to an increase in the size of the interchangeable lens  1 . 
     For those reasons, the configuration is suitable that the seventh unit connection screw  88  according to the present exemplary embodiment fitted in the long hole  710  allows the motor movement base  85  and the sixth lens drive motor unit  95  to move integrally with the seventh unit  70  in the optical axis direction. 
     As illustrated in  FIG. 11B , the position of the straight groove  812  is defined as a point M and the position of the straight groove  813  is defined as a point N. In the present exemplary embodiment, the distances between the seventh unit connection screw  88  and the point M and between the seventh unit connection screw  88  and the point N in directions orthogonal to the groove direction of each straight groove are short. The distance between the seventh unit connection screw  88  and the plane passing through the point F, the point G, and the point H is short. In other words, the seventh unit connection screw  88  partially overlaps the motor movement base  85  or the sixth lens drive motor unit  95  as viewed on the image plane. That configuration reduces the effect of the force transmitted to the motor movement base  85  in the optical axis direction by the movement of the seventh unit  70  in zooming on the urging force that stably holds the motor movement base  85 . 
       FIG. 13  is a perspective view illustrating an image capturing apparatus  1000  including the interchangeable lens  1  according to the exemplary embodiment of the disclosure. The image capturing apparatus  1000  includes the interchangeable lens  1  serving as the lens apparatus, and a camera body  200  on which the interchangeable lens  1  is detachably mountable with the mount. The interchangeable lens  1  includes a control unit, a lens drive instruction unit, and a contact portion communicable with the camera body  200 . The camera body  200  includes a control unit, an image sensor, and a contact portion communicable with the interchangeable lens  1 . The image capturing apparatus  1000  according to an exemplary embodiment of the disclosure is not limited to an image capturing system. Examples of the image capturing apparatus  1000  include a lens interchangeable camera and a lens-integrated camera. Examples of the camera include an image capturing apparatus such as a digital still camera and a video camera. 
     The interchangeable lens  1  houses an image capturing optical system to form an optical image of an object (subject). An image capturing luminous flux from an object passes through the image capturing optical system to form an image on the light-receiving surface (imaging plane) of the image sensor. The image sensor photoelectrically converts the optical image of the object formed by the image capturing optical system. 
     According to an aspect of the embodiments, a compact lens apparatus is provided that allows the lenses to be stably driven a longer distance. While the exemplary embodiments of the disclosure have been described above, the disclosure is not limited to them and can be changed or modified in various ways within the scope of the disclosure. 
     While the disclosure has been described with reference to exemplary embodiments, it is to be understood that the disclosure is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions. 
     This application claims the benefit of Japanese Patent Application No. 2021-004607, filed Jan. 15, 2021, which is hereby incorporated by reference herein in its entirety.