Lens barrel and camera equipped therewith

Abstract

To provide a lens barrel and a camera with the same that can evade trouble such as breakage of a component when a teleconverter is mounted.SOLUTION: A lens barrel 10 comprises a lens mount 23, a 5-group unit 17, a cam frame 13, a cam pin 17c, a cam pin holder 17b, a main shaft 17g, and an energizing spring 17f. The cam frame 13 encloses the 5-group unit 17, and has a cam groove 13a. The cam pin 17c moves along an optical axis while engaging the cam groove 13a. The cam pin holder 17b is provided for the 5-group unit 17 relatively movably along the optical axis, and holds the cam pin 17c. The main shaft 17g enables the 5-group unit 17 to move along the optical axis. The energizing spring 17f is provided for the 5-group unit 17 to energize the cam pin holder 17b toward a subject in the optical axis direction, and expands / contracts with a teleconverter 30 mounted on the lens mount 23 to retract the 5-group unit 17 along the optical axis.SELECTED DRAWING: Figure 7B

Description

Technical Field

[0001] The present disclosure relates to a lens barrel and a camera including the same.

Background Art

[0002] In recent years, lens barrels that include an optical system having a plurality of lenses and are detachably attached to a camera body have been used. In such a lens barrel, a teleconverter for extending the focal length may be attached between the lens barrel and the camera body. The teleconverter can extend the focal length of the lens barrel by being attached to the mount portion of the camera body and the mount portion of the lens barrel, respectively.

[0003] At this time, there is a risk that a member on the teleconverter side interferes with the member provided on the most camera body side in the optical axis direction of the lens barrel, resulting in damage to the components. For example, in Patent Document 1, in order to prevent deterioration of the optical performance of the imaging optical system due to an external force applied to the lens barrel, a cam ring is composed of a lens support ring portion formed with an inner cam groove and a tip outer peripheral ring portion that is a separate member from the lens support ring portion and is supported on the outer periphery of the tip portion of the lens support ring portion so as to rotate together in the rotational direction. The tip outer peripheral ring portion is supported with a clearance in the optical axis direction with respect to the lens support ring portion, and a biasing spring that biases the tip outer peripheral ring portion to move in the optical axis direction is inserted into the clearance portion in the optical axis direction between the tip outer peripheral ring portion and the lens support ring portion. A zoom lens barrel is disclosed in which the tip outer peripheral ring portion flexes when an external force acts on the lens barrel from the outside.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, the conventional zoom lens barrel described above has the following problems. In other words, the zoom lens barrel disclosed in the above-mentioned publication employs a configuration in which, when an external force is applied to the outer barrel, a compression spring compresses and the second cam barrel is displaced, thereby preventing damage to the internal lens frame, while a rotation stopper allows it to retract only in the optical axis direction.

[0006] However, with this configuration, when a teleconverter is attached between the camera body and the telescope, the components of the teleconverter and the lens frame of the lens barrel may interfere with each other in the optical axis direction, potentially causing malfunctions such as component damage. The objective of this disclosure is to provide a lens barrel and a camera equipped therewith that can avoid malfunctions such as damage to components, even when a teleconverter is attached. [Means for solving the problem]

[0007] The lens barrel according to this disclosure is a lens barrel that is attached to a camera body in an interchangeable manner and comprises a mounting portion, a retractable lens frame, a substantially cylindrical cam frame, a cam pin, a cam pin holder, a first guide shaft, and a biasing spring. The mounting portion is to which a teleconverter is attached. The retractable lens frame includes an optical lens that interferes in the optical axis direction when the teleconverter is attached. The substantially cylindrical cam frame encloses the retractable lens frame and has a cam groove. The cam pin protrudes in a direction intersecting the optical axis direction and moves in the optical axis direction while engaged with a cam groove formed in the cam frame. The cam pin holder is provided on the retractable lens frame in a manner that allows relative movement in the optical axis direction and holds the cam pin. The first guide shaft is arranged along the optical axis direction and allows the retractable lens frame to move in the optical axis direction. The biasing spring is provided on the retractable lens frame and biases the cam pin holder toward the subject side in the optical axis direction, and when the teleconverter is attached to the mounting portion, it extends and retracts to retract the retractable lens frame in the optical axis direction. [Effects of the Invention]

[0008] According to the lens barrel described herein, even when a teleconverter is attached, it is possible to avoid malfunctions such as damage to parts. [Brief explanation of the drawing]

[0009] [Figure 1A] A perspective view showing the optical system of a lens barrel, including a lens hood holding structure according to one embodiment of the present disclosure, in the wide-angle position. [Figure 1B] Figure 1A is a perspective view showing the optical system of the lens barrel moved to the telephoto side (TELE position). [Figure 2A] Cross-sectional view of the lens barrel in Figure 1A. [Figure 2B] Cross-sectional view of the lens barrel in Figure 1B. [Figure 3] Figure 1A shows an exploded perspective view of the individual components that make up the lens barrel. [Figure 4A] A side view showing the lens barrel before the teleconverter is attached, as shown in Figure 1. [Figure 4B] Figure 4A is a side view showing the lens barrel with a teleconverter attached to the end opposite to the subject side. [Figure 5A] Side cross-sectional view, Figure 4A. [Figure 5B] Figure 4B is a side cross-sectional view. [Figure 6] Figure 5B is a side view showing the interference avoidance state when the lens barrel is in the TELE position with the teleconverter attached. [Figure 7A] Figure 1 shows a perspective view of the five-group unit included in the lens barrel before the teleconverter is attached. [Figure 7B] Figure 1 is a perspective view showing a teleconverter attached to a 5-group unit included in the lens barrel. [Figure 8A] A side view showing the state of the 5-group unit included in the lens barrel (Figure 1, etc.) before the teleconverter is attached. [Figure 8B] This is a side cross-sectional view showing a state in which a teleconverter is attached to a 5-group unit contained in the lens barrel of Figure 1, etc., to avoid lens interference. [Figure 9] Perspective view showing the configuration of the five-group unit of FIG. 7A. [Figure 10] Cross-sectional view showing the positional relationship of the cam pin, cam cylinder, and fixed cylinder included in the five-group unit of FIG. 9. [Figure 11] Exploded perspective view showing the configuration of the five-group unit of FIG. 9. [Figure 12A] Side view showing the state where the rear frame of the lens barrel such as in FIG. 1 is removed. [Figure 12B] Front view showing the configuration of the side where the teleconverter of the lens barrel of FIG. 12A is mounted. [Figure 13] Perspective view showing the zoom encoder and zoom drive pin that are exposed when the rear frame of the lens barrel of FIG. 1 is removed. [Figure 14A] Front view showing the configuration of the connection side of the teleconverter of FIG. 4B with the lens barrel. [Figure 14B] Side view of the teleconverter of FIG. 14A. [Figure 14C] Rear view showing the configuration of the connection side of the teleconverter of FIG. 14A with the camera body. [Figure 15] Control block diagram showing the configuration of the camera system of FIG. 1. [Figure 16] Perspective view showing the configuration of the five-group unit included in the lens barrel according to another embodiment of the present disclosure. [Figure 17A] Side view showing the state before the teleconverter is mounted on the five-group unit of FIG. 16. [Figure 17B] Side view showing the state after the teleconverter is mounted on the five-group unit of FIG. 16.

Embodiments for Carrying Out the Invention

[0010] Hereinafter, embodiments will be described in detail with reference to the drawings as appropriate. However, detailed descriptions that are more than necessary may be omitted. For example, detailed descriptions of well-known matters and redundant descriptions of substantially the same configurations may be omitted. This is to avoid making the following description unnecessarily redundant and to facilitate the understanding of those skilled in the art. The applicant provides the accompanying drawings and the following description so that a person skilled in the art can fully understand the disclosure, and not intends to limit the subject matter described in the claims.

[0011] (Embodiment 1) A lens barrel 10 and a camera 100 equipped therewith, according to one embodiment of this disclosure, will be described below with reference to Figures 1 to 15. (Overall configuration of the lens barrel 10) The lens barrel 10 according to this embodiment, together with the teleconverter 30 described later, is attached to the mount portion of the camera body 50 in a manner that allows it to be detachably attached to the camera body 50, thereby constituting the camera 100 (see Figure 15). The lens barrel 10 has an optical system (lenses L1 to L20 (see Figure 2A, etc.)) that guides the subject image to the image sensor provided on the camera body 50.

[0012] Furthermore, as shown in Figures 1A and 1B, the lens barrel 10 can perform variable magnification photography by moving its built-in optical system between the wide-angle side (WIDE position) and the telephoto side (TELE position). When the lens barrel 10 is in the WIDE position shown in Figure 1A, the first group unit 11 is housed on the inner circumferential side of the outer unit 19, as shown in Figure 2A.

[0013] On the other hand, when the lens barrel 10 is in the TELE position shown in Figure 1B, the first group unit 11 extends toward the subject along the optical axis X direction, as shown in Figure 2B, and protrudes from the outer unit 19 toward the subject. As shown in Figure 3, the lens barrel 10 comprises an optical system consisting of a 1st group unit 11, a 2nd group unit 12, a cam frame 13, a fixed frame 14, a 3rd group unit 15, a 4th group unit 16, a 5th group unit (retractable lens frame) 17, a mount base 18, an exterior unit 19, a rear frame 20, a control board (display control unit) 21, a lens mounting indicator ring unit 22, a lens mount (mounting part) 23, and multiple lenses L1 to L20. The teleconverter 30 is mounted between the end of the lens barrel 10 opposite to the subject side (lens mount 23 side) in the optical axis X direction of the lenses L1 to L20 and the camera body 50.

[0014] As shown in Figure 3, the first group unit 11 is a cylindrical component positioned closest to the subject in the lens barrel 10. As shown in Figures 2A and 2B, the first group unit 11 moves forward and backward along the optical axis X direction while holding lenses L1 to L3 on the subject side. This changes the distance between lenses L1 to L20, enabling wide-angle and telephoto photography.

[0015] As shown in Figures 2A and 2B, the second group unit 12 is a cylindrical member positioned on the inner circumferential side of the first group unit 11, and holds the lenses L4 to L9. As shown in Figure 3, the cam frame 13 is a cylindrical member and is positioned on the outer circumferential surface side of the 4-group unit 16. The cam frame 13 has a cam groove 13a into which the cam pins (not shown) of the 4-group unit 16 and the cam pins 17c provided on the outer circumferential surface of the 5-group unit 17 are fitted.

[0016] As a result, the cam pin 17c and the like move along the cam groove 13a in response to the rotational driving force provided by a rotational drive source (not shown), allowing the 1st group unit 11 to the 5th group unit 17 to be moved back and forth in the optical axis X direction. Therefore, the distance between each lens L1 to L20 included in the 1st group unit 11 to the 5th group unit 17 can be adjusted to perform wide-angle photography, telephoto photography, etc.

[0017] As shown in Figure 3, the fixing frame 14 is a cylindrical member positioned on the outer circumference of the cylindrical group 1 unit 11 and group 4 unit 16, and is positioned to cover the outer circumferential surfaces of group 1 unit 11 to group 4 unit 16. The fixing frame 14 also has a through groove 14a that connects the substantially cylindrical inner circumferential surface and the outer circumferential surface. The through groove 14a is into which a cam pin 17c or the like is inserted. The cam pin 17c moves along the cam groove 13a of the cam frame 13 while engaged with the cam groove 13a via the through groove 14a.

[0018] As shown in Figure 3, the 3-group unit 15 is positioned on the inner circumference of the cylindrical 4-group unit 16 in a manner that allows it to move in the optical axis X direction. The 3-group unit 15 is driven by an actuator (not shown) to move back and forth in the optical axis X direction while holding the lenses L10 to L17. The 4-group unit 16 has a roughly cylindrical shape and, as shown in Figure 3, is positioned downstream of the 3-group unit 15 when viewed from the subject side in the optical axis X direction. The 4-group unit 16 holds the lens L18.

[0019] As shown in Figure 3, the 5-group unit 17 is positioned on the inner circumference of the cylindrical 4-group unit 16 in a manner that allows it to move in the optical axis X direction. The 5-group unit 17, while holding the lenses L19 and L20, is driven by an actuator (not shown) to move back and forth in the optical axis X direction. As shown in Figure 3, the mount base 18 is a substantially cylindrical member that serves as the base for the lens barrel 10, and the 4-group unit 16 is fixed to its inner circumferential surface. A cam frame 13 is also attached to the mount base 18 in a manner that allows for relative rotation.

[0020] As shown in Figures 1A and 4, the exterior unit 19 is a cylindrical member that constitutes the exterior portion of the lens barrel 10, and an annular focus ring 19a, a zoom ring 19b, etc., are attached to its outer surface in a rotatable manner. The rear frame 20 is attached to the end of the exterior unit 19 opposite to the subject, and together with the exterior unit 19, it constitutes the exterior portion of the lens barrel 10. The rear frame 20 is mounted so as to rotate relative to the mount base 18 and the exterior unit 19.

[0021] The control board 21 is located near the end of the lens barrel 10 opposite to the subject side in the optical axis X direction. The control board 21 is connected to a zoom encoder 25 (see Figures 12A, 13, etc.), which will be described later, and controls actuators (not shown) that change the relative positions of lenses L1 to L20 based on the zoom position (magnification position) of the lens group detected by the zoom encoder 25.

[0022] The lens mounting indicator ring unit 22 is a substantially annular member provided at the end of the lens barrel 10 opposite to the subject side in the optical axis X direction, and is marked with a mark indicating the reference position in the rotational direction around the optical axis X when it is attached to the camera body 50 or teleconverter 30. The lens mount (mounting part) 23 is fixed to the mount base 18 and, when the lens barrel 10 is attached to the camera body 50 or teleconverter 30, it is locked to the mount provided on the main body 31 of the camera body 50 or teleconverter 30.

[0023] The teleconverter 30 is a roughly cylindrical auxiliary member that extends the focal length of the lens barrel 10, for example, to enable 1.4x telephoto shooting. As shown in Figures 4A and 4B, the teleconverter 30 is attached to the end of the lens barrel 10 that connects to the camera body 50 (lens mount 23), and contains multiple lenses L21 to L26 (see Figure 5B, etc.) inside.

[0024] Here, when the teleconverter 30 is attached to the end of the lens barrel 10 shown in Figure 5A that is opposite to the subject in the optical axis X direction, the lens group (lenses L19, L20) included in the 5-group unit 17 and the lens group (L21~L26) included in the teleconverter 30 interfere with each other at the WIDE position shown in Figure 5B. In other words, the lenses L19 and L20 included in the 5-group unit 17 on the lens barrel 10 side are positioned at the end of the lens barrel 10 opposite to the subject in the optical axis X direction when in the WIDE position. On the other hand, the lens group included in the teleconverter 30 is positioned to protrude toward the connection side with the lens barrel 10.

[0025] Therefore, when the teleconverter 30 is attached while the lens barrel 10 is in the WIDE position shown in Figure 5B, the lens group included in the 5-group unit 17 (lenses L19, L20) and the lens group included in the teleconverter 30 (L21~L26) interfere with each other by the amount of interference width shown in Figure 5B. Here, with the lens barrel 10 shown in Figure 5A mounted on the end opposite to the subject in the optical axis X direction, when it moves to the TELE position shown in Figure 6, the lens group included in the 5-group unit 17 (lenses L19, L20) and the lens group included in the teleconverter 30 (L21~L26) do not interfere with each other.

[0026] Therefore, the lens barrel 10 of this embodiment is equipped on the 5-group unit 17 side with a retraction mechanism (cam pin holder 17b, biasing spring 17f, etc.) to avoid interference between the lenses L19 and L20 and the lens L21, etc. on the teleconverter 30 side in the WIDE position. Specifically, as shown in Figures 7A and 7B, the 5-group unit 17 includes a main body 17a that holds the lenses L19 and L20, a cam pin holder 17b, a cam pin 17c, a cam pin holder guide shaft (second guide shaft) 17d, a rotation restricting part 17e, a biasing spring 17f, a main shaft (first guide shaft) 17g, a sub-shaft (first guide shaft) 17h, and a cushioning material (buffer member) 17i.

[0027] Then, when the teleconverter 30 is attached to the end of the lens barrel 10 on the opposite side from the subject (image plane side) in the optical axis X direction shown in Figure 8A, the 5-group unit 17 retracts in the direction of the black arrow in Figure 8B to avoid interference with the teleconverter 30. At this time, the cam pin holder 17b, which holds the cam pin 17c included in the 5-group unit 17, does not move while the cam pin 17c remains engaged with the cam groove 13a of the cam frame 13.

[0028] As a result, as shown in Figures 8A and 8B, even when the teleconverter 30 is attached, only the main body 17a included in the 5-group unit 17 moves toward the subject in the optical axis X direction. Therefore, when the teleconverter 30 is attached, the main body 17a that holds the lenses L19 and L20 is retracted, while the position of the cam pin holder 17b that holds the cam pin 17c remains unchanged, thereby eliminating any influence on other lens frames due to the rotation of the cam frame 13, etc.

[0029] As shown in Figure 9, the main body 17a has a substantially annular lens holding portion (holding portion) 17aa that holds the lenses L19 and L20, and an extended portion 17ab that holds the main shaft 17g and extends from the substantially annular portion along the optical axis X direction. As shown in Figure 9, the cam pin holder 17b is provided in a groove formed in the extended portion 17ab of the main body portion 17a. The cam pin holder 17b moves relative to the lens holding portion 17aa of the main body portion 17a by moving within the extended portion 17ab along the optical axis X direction.

[0030] Furthermore, as shown in Figure 10, the cam pin holder 17b has a recess 17ba, a projection 17bb, and an insertion hole 17bc. As shown in Figure 10, the recess 17ba opens radially outward and holds the cam pin 17c in place. As shown in Figures 9 and 10, the projection 17bb is formed to protrude in a direction intersecting the optical axis X. The projection 17bb is positioned to overlap the inclined surface that forms the through groove 14a of the fixed frame 14.

[0031] As a result, for example, even if an external impact is applied and the cam pin 17c is about to detach from the cam groove 13a of the cam frame 13, the projection 17bb of the cam pin holder 17b that holds the cam pin 17c restricts the radially inward movement of the cam pin holder 17b, thereby effectively preventing the cam pin 17c from detaching from the cam groove 13a. As shown in Figure 10, the insertion hole 17bc is formed to penetrate the extended portion 17ab of the cam pin holder 17b along the optical axis X direction, and the main shaft 17g is inserted into it.

[0032] Here, the spindle 17g inserted into the insertion hole 17bc is positioned such that a predetermined gap is formed between the inner surface of the insertion hole 17bc and the outer surface of the spindle 17g, as shown in Figure 10. As a result, the 5-group unit 17 can move smoothly along the optical axis X direction without its movement being hindered by friction or other factors between the main shaft 17g and the cam pin holder 17b.

[0033] As shown in Figure 10, the cam pin 17c is held in the recess 17ba of the cam pin holder 17b and is positioned to protrude radially outward, with its tip engaging with the cam groove 13a of the cam frame 13. As a result, when the cam frame 13 rotates relative to the cam, the cam pin 17c engaged with the cam groove 13a is moved in the optical axis direction, thereby changing the relative positions of the lenses L1 to L20 included in the lens barrel 10.

[0034] As shown in Figure 10, the cam pin spring 17ca is positioned in a recess 17ba provided in the cam pin holder 17b so as to fit onto the outer circumferential surface of the base portion of the cam pin 17c, thereby biasing the cam pin 17c radially outward. As shown in Figures 7B and 10, the cam pin holder guide shaft (second guide shaft) 17d is positioned along the optical axis X direction within the extension portion 17ab of the main body portion 17a. The cam pin holder guide shaft 17d supports the cam pin holder 17b in a manner that allows it to move back and forth in the optical axis X direction. A biasing spring 17f is also positioned on the outer circumferential surface of the cam pin holder guide shaft 17d to bias the cam pin holder 17b in the optical axis X direction.

[0035] As a result, the cam pin holder 17b, which moves along the cam pin holder guide axis 17d, is held within the extension portion 17ab of the main body portion 17a while being biased in the optical axis X direction by the biasing spring 17f. As shown in Figure 10, the rotation restricting portion 17e has contact portions 17ea that abut against the cam pin holder 17b at both radial ends. By abutting the cam pin holder 17b at the contact portions 17ea, the rotation restricting portion 17e restricts the rotation of the cam pin holder 17b around the cam pin holder guide axis 17d.

[0036] As shown in Figure 11, the biasing spring 17f is held wound around the outer circumference of the cam pin holder guide shaft 17d, and biases the side surface of the cam pin holder 17b, which moves in the optical axis X direction along the cam pin holder guide shaft 17d, in the optical axis X direction. When the teleconverter 30 is mounted on the lens mount 23, the biasing spring 17f contracts, causing the main body portion 17a included in the 5-group unit 17 to move in the optical axis X direction without changing the position of the cam pin holder 17b, thereby retracting it so as not to interfere with the lens L21 on the teleconverter 30 side.

[0037] Furthermore, when the teleconverter 30 is not attached, the biasing spring 17f has a biasing force such that the distance between the lens holding portion 17aa and the cam pin holder 17b held by the extension portion 17ab does not change when the cam pin 17c moves along the cam groove 13a due to the rotation of the cam frame 13. This eliminates the influence of the extension and contraction of the biasing spring 17f when driving the cam pin 17c, etc., along the cam groove 13a to change the relative position of the lenses L1 to L20 to the WIDE position or TELE position.

[0038] On the other hand, the biasing spring 17f extends and retracts only when the teleconverter 30 is attached to the lens barrel 10, thereby avoiding interference with the 5-group unit 17 when the teleconverter 30 is attached. As shown in Figure 9, the main shaft (first guide shaft) 17g is positioned along the optical axis X direction and guides the 5-group unit 17 in the optical axis X direction. As shown in Figure 10, the main shaft 17g is inserted into the insertion hole 17bc provided in the cam pin holder 17b, and the cam pin holder 17b is supported in such a state that it can move back and forth in the optical axis X direction.

[0039] As shown in Figure 9, the sub-axis (first guide axis) 17h is positioned approximately parallel to the main axis 17g and supports the outer circumference of the lens holding portion 17aa of the main body portion 17a of the 5-group unit 17. As a result, the 5-group unit 17 moves back and forth in the optical axis X direction while being supported by the main axis 17g and the sub-axis 17h.

[0040] The cushioning material (buffer member) 17i is an elastic member attached to the end of the 5-group unit 17 opposite to the subject in the optical axis direction. As shown in Figure 11, the cushioning material 17i holds the lenses L19 and L20 between the main body portion 17a of the 5-group unit 17 and the lens holding portion 17aa. As a result, when attaching the teleconverter 30 to the lens mount 23 of the lens barrel 10, even if the lens L21 or other components of the teleconverter 30 come into contact with the components of the 5-group unit 17, the cushioning effect of the cushioning material 17i can reduce the impact of the contact.

[0041] In this embodiment, the lens barrel 10 is equipped on the 5-group unit 17 side with a retraction mechanism (cam pin holder 17b, biasing spring 17f, etc.) to avoid interference between the lenses L19 and L20 and the lens L21 on the teleconverter 30 side in the WIDE position. Furthermore, in the lens barrel 10 of this embodiment, when the teleconverter 30 is attached, the lenses L19 and L20 of the 5-group unit 17 are not in their normal position but in a retracted position. Therefore, the lens barrel 10 is equipped with a control board (display control unit) 21 (see Figure 15) that performs display control to alert the user to the need for caution during shooting.

[0042] The control board 21 is connected to the zoom encoder 25, and the output from the zoom encoder 25 detects whether the position of lenses L1 to L20 is in the WIDE position or the TELE position. As shown in Figures 12A and 13, the zoom encoder 25 is located on the inner circumference of the zoom ring 19b and detects the relative positions of the lenses L1 to L20 included in the lens barrel 10.

[0043] Furthermore, the rotation of the zoom ring 19b is transmitted to a zoom drive pin 28, which is provided to protrude toward the inner circumference of the zoom ring 19b, as shown in Figure 13. The zoom drive pin 28 engages with a cam groove formed in the cam frame 13 described above. When the zoom ring 19b is rotated manually, the cam frame 13 rotates via the zoom drive pin 28, changing the relative positions of the lenses L1 to L20 contained in the lens barrel 10.

[0044] Furthermore, as shown in Figure 12B, the control board 21 is electrically connected to the teleconverter 30 or the camera body 50 via electrical contacts (lens contact 26 and teleconverter detection contact 27) provided at the end of the lens barrel 10 opposite to the optical axis direction. Similarly, as shown in Figures 14A, 14B, and 14C, the teleconverter 30 includes a main body 31, a lens contact 32 (see Figure 14C) provided on the side of the main body 31 that connects to the camera body 50, and a lens contact pin 33 and a teleconverter detection pin 34 (see Figure 14A) provided on the side of the main body 31 that connects to the lens barrel 10.

[0045] The lens contact 32 is positioned to contact a contact pin 53 provided on the camera body 50 when the teleconverter 30 is attached to the camera body 50. This allows the camera body 50 to transmit and receive various signals with the teleconverter 30 via the lens contact 32. As shown in Figure 14A, the lens contact pin 33 is located on the side that connects to the lens barrel 10. When the teleconverter 30 is attached to the lens barrel 10, the lens contact pin 33 is electrically connected to the lens contact 26 on the lens barrel 10 side. In addition, as shown in Figure 15, the lens contact pin 33 is electrically connected to the lens contact 32 inside the teleconverter 30.

[0046] The teleconverter detection pin 34, like the lens contact pin 33, is located on the side connected to the lens barrel 10, as shown in Figure 14A. When the teleconverter 30 is attached to the lens barrel 10, the teleconverter detection pin 34 is electrically connected to the teleconverter detection contact 27 on the lens barrel 10 side. In addition, as shown in Figure 15, the teleconverter detection pin 34 is electrically connected to the lens contact 32 within the teleconverter 30.

[0047] In the lens barrel 10 of this embodiment, when the teleconverter 30 is mounted between the camera body 50 and the lens barrel 10, the control board 21 detects the connection status between the teleconverter detection contact 27 and the teleconverter detection pin 34 and transmits a signal to the camera body 50 indicating that the teleconverter 30 is mounted. On the other hand, when the teleconverter 30 is not installed between the camera body 50 and the lens barrel 10, the control board 21 cannot detect the connection status between the teleconverter detection contact 27 and the teleconverter detection pin 34, and therefore does not transmit a signal to the camera body 50 indicating that the teleconverter 30 is installed.

[0048] This allows the camera body 50 to determine whether or not the teleconverter 30 is attached, based on whether or not it receives a signal from the control board 21 of the lens barrel 10. Furthermore, in the lens barrel 10 of this embodiment, as shown in Figure 15, when the teleconverter 30 is mounted between the camera body 50 and the lens barrel 10, as described above, the positions of the lenses L19 and L20 included in the 5-group unit 17 may move due to the expansion and contraction of the biasing spring 17f, and may be retracted to a position other than the normal position.

[0049] Therefore, when the teleconverter 30 is attached, the control board 21 receives a signal indicating the relative positions (e.g., WIDE position, TELE position) of the lenses L1 to L20 included in the lens barrel 10 detected by the zoom encoder 25, and transmits a display control signal to display a message on the display panel 52 of the camera body 50 prompting the use of the TELE side.

[0050] As a result, the control board 51 of the camera body 50, which receives display control signals from the control board 21 of the lens barrel 10 via the lens contact 26, lens contact pin 33, lens contact 32, and contact pin 53, can control the display panel 52 to display a message prompting the user to use the TELE side. Therefore, by looking at the warning message displayed on the display panel 52 of the camera body 50, the user can recognize that proper shooting is not possible in the WIDE position because the lens position is not appropriate.

[0051] As a result, when the teleconverter 30 is attached, the conditions under which proper shooting can be performed while avoiding interference between the lens barrel 10 and the teleconverter 30 can be displayed on the display panel 52 of the camera body 50. <Main Features> As shown in Figures 8A and 8B, the lens barrel 10 of this embodiment comprises a lens mount 23, a 5-group unit 17, a cam frame 13, a cam pin 17c, a cam pin holder 17b, a main shaft 17g and a sub-shaft 17h, and a biasing spring 17f. The lens mount 23 is to which the teleconverter 30 is mounted. The 5-group unit 17 includes a lens L21, etc., which interferes in the optical axis direction when the teleconverter 30 is mounted. The cam frame 13 encloses the 5-group unit 17 and has a cam groove 13a. The cam pin 17c protrudes in a direction intersecting the optical axis direction and moves in the optical axis direction while engaged with the cam groove 13a. The cam pin holder 17b is provided on the 5-group unit 17 in a state that allows relative movement in the optical axis direction and holds the cam pin 17c. The main shaft 17g and sub-shaft 17h are arranged along the optical axis direction and allow the 5-group unit 17 to move in the optical axis direction. The biasing spring 17f is provided on the 5-group unit 17 and biases the cam pin holder 17b toward the subject in the optical axis direction. When the teleconverter 30 is attached to the lens mount 23, the spring contracts and retracts the 5-group unit 17 in the optical axis direction.

[0052] As a result, when the teleconverter 30 is attached to the lens barrel 10 on the side opposite to the subject (image plane side) in the optical axis direction, the main body 17a, which holds the lenses L19 and L20 included in the 5-group unit 17 located closest to the image plane of the lens barrel 10, comes into contact with the lens L21 and other lenses included in the teleconverter 30 and is pressed in the optical axis direction. At this time, the main body 17a moves relative to the cam pin holder 17b as the biasing spring 17f contracts.

[0053] In other words, when the teleconverter 30 is attached to the lens barrel 10, only the main body 17a that holds the lenses L19 and L20 of the 5-group unit 17 moves in the optical axis direction, while the cam pin holder 17b is held without moving in the optical axis direction. Therefore, even when the teleconverter 30 is attached, it is possible to avoid malfunctions such as damage to the lens barrel 10 and the components included in the teleconverter 30.

[0054] [Other embodiments] Although one embodiment of the present disclosure has been described above, the present disclosure is not limited to the above embodiment, and various modifications are possible without departing from the gist of the disclosure. (A) In the above embodiment, an example was described in which the relative position of the lenses L1 to L20 included in the lens barrel 10 is changed by the relative rotation of the cam frame 13 around the optical axis X, which moves the cam pin 17c and the like engaged in the cam groove 13a, thereby enabling imaging in WIDE position and TELE position. However, this disclosure is not limited to this.

[0055] For example, as shown in Figure 16, instead of the cam pin 17c that engages with the cam groove 13a of the cam frame 13, a 5-group unit (retractable lens frame) 117 may be provided with a rack 117c that is driven back and forth along the optical axis by a stepping motor unit (drive unit) 117d. The 5-group unit 117 comprises a main body 117a, a rack holder 117b, a rack 117c, a stepping motor unit 117d, a biasing spring 17f, a main spindle 17g, and a sub-spindle 17h.

[0056] Since the biasing spring 17f, main shaft 17g, and sub-shaft 17h have the same configuration as in Embodiment 1 described above, a detailed explanation of them will be omitted. As shown in Figure 16, the main body 117a has a lens holding portion 117aa that holds the lenses L19 and L20, and an extended portion 117ab that extends from the outer periphery of the lens holding portion 117aa along the optical axis.

[0057] The rack holder 117b is provided on the 5-group unit 117 in a manner that allows relative movement in the optical axis direction, and holds the rack 117c. Furthermore, similar to the cam pin holder 17b in the first embodiment described above, the rack holder 117b is biased along the optical axis direction by a biasing spring 17f. The rack 117c is positioned to protrude in a direction intersecting the optical axis direction and moves along the optical axis direction while being held by the rack holder 117b.

[0058] The stepping motor unit 117d is a unit that includes a stepping motor, and moves the rack holder 117b back and forth in the optical axis direction by the rotational driving force of the stepping motor. The lens barrel of this embodiment has the above configuration, and when a teleconverter is attached to the end of the 5-group unit 117 shown in Figure 17A that is opposite to the subject side in the optical axis direction, the lens holding portion 117aa comes into contact with the teleconverter and retracts toward the subject side in the optical axis direction, similar to the 5-group unit 17 of Embodiment 1 (see Figure 17B).

[0059] At this time, the lens holder 117aa retracts towards the subject in the optical axis direction by the amount of interference with the teleconverter side, while the rack 117c held by the rack holder 117b does not move in the optical axis direction. In other words, the rack holder 117b is biased in the optical axis direction by the biasing spring 17f, and when the teleconverter is attached, the biasing spring 17f contracts, causing only the lens holding portion 117aa of the 5-group unit 117 to move in the optical axis direction, while the position of the rack holder 117b remains unchanged.

[0060] Therefore, according to the configuration of this embodiment, as shown in Figures 17A and 17B, even when a teleconverter is attached, it is possible to avoid problems such as damage to parts on the lens barrel side or the teleconverter side. (B) In the above embodiment, when the teleconverter 30 is attached, the biasing spring 17f included in the 5-group unit (retractable lens frame) 17 is reduced, causing the main body portion 17a of the 5-group unit 17 to move toward the cam pin 17c (cam pin holder 17b). However, this disclosure is not limited to this.

[0061] For example, in a configuration where the biasing spring is positioned on the subject side in the optical axis direction of the cam pin holder, when the teleconverter is attached, the biasing spring 17f is pulled, causing the main body 17a of the 5-group unit 17 to move in a direction toward the cam pin 17c (cam pin holder 17b). (C) In the above embodiment, an example was given in which a 5-group unit 17 was used as the retractable lens frame to be moved when the teleconverter 30 is attached. However, this disclosure is not limited to this.

[0062] For example, the retractable lens frame that is moved out when a teleconverter is attached is not limited to a 5-group unit; it may be any other lens group unit. (D) In the above embodiment, an example was given in which the 5-group unit 17, which serves as a retractable lens frame, moves back and forth in the optical axis direction along two guide axes, the main axis 17g and the sub-axis 17h. However, this disclosure is not limited thereto.

[0063] For example, the guide axis that guides the retractable lens frame in the optical axis direction may be one or three or more. (E) In the above embodiment, an example was described in which a cushioning material 17i is provided at the end of the 5-group unit 17 on the side to which the teleconverter 30 is attached, to absorb the impact when the member on the teleconverter 30 side and the member on the 5-group unit 17 side come into contact. However, this disclosure is not limited thereto.

[0064] For example, if the components on the teleconverter side and the components on the retractable lens frame side have sufficient strength to prevent damage or other malfunctions even if they collide with each other, then a configuration without cushioning material (buffering member) is acceptable. (F) In the above embodiment, an example was described in which, upon detecting that the teleconverter 30 is attached and that the lens position detected by the zoom encoder 25 is on the WIDE side, a message prompting use on the TELE side is displayed on the display panel 52 of the camera body 50. However, this disclosure is not limited to this.

[0065] For example, if the camera detects the attachment of a teleconverter, it may display a message indicating that shooting in WIDE mode is disabled. [Industrial applicability]

[0066] The lens barrel of this disclosure has the effect of preventing malfunctions such as damage to parts even when a teleconverter is attached, and is therefore widely applicable to lens barrels attached to various cameras. [Explanation of Symbols]

[0067] 10 Lens barrel 11 Group 1 Unit 12 Group 2 Units 13 Cam frame 13a Cam groove 14 Fixed frame 14a Through groove 15 Group 3 Unit 16 4-group unit 17. 5-group unit (retractable lens frame) 17a Main body 17aa Lens holder (holding part) 17ab extension part 17b Cam pin holder 17ba recess 17bb protrusion 17bc insertion hole 17c cam pin 17ca cam pin spring 17d Cam pin holder guide axis (second guide axis) 17e Rotation restricting section 17ea Contact part 17f biasing spring 17g Main shaft (first guide shaft) 17h Sub-axis (First guide axis) 17i Cushioning material (cushioning material) 18 Mounting Base 19 Exterior Units 19a Focus Ring 19b Zoom Ring 20 Last slot 21 Control board (display control unit) 22 Lens mounting indicator ring unit 23. Lens mount (mounting part) 25 Zoom Encoder 26 Lens contacts 27 Teleconverter detection contact (attachment detection unit) 28 zoom drive pins 30 Teleconverter 31 Main body 32 lens contacts 33 Lens contact pins 34 Teleconverter detection pins 50 Camera body 51 Control board 52 Display panel (display unit) 53 Contact pins 100 Cameras 117 5-group unit (retractable lens frame) 117a Main body 117aa Lens holder 117ab extension part 117b Rack holder 117c rack 117d Stepping motor unit (drive unit) L1~L20 Lenses (Optical Lenses) L21~L26 Lenses (Optical Lenses) X optical axis

Claims

1. A lens barrel that is attached to the camera body in a replaceable manner, The mounting section to which the teleconverter is attached, When the teleconverter is attached, the retractable lens frame includes an optical lens that interferes in the optical axis direction, A substantially cylindrical cam frame having a cam groove encloses the aforementioned retractable lens frame, A cam pin that protrudes in a direction intersecting the optical axis direction and moves in the optical axis direction while engaged with the cam groove formed in the cam frame, A cam pin holder is provided on the retractable lens frame in a manner that allows relative movement in the optical axis direction, and holds the cam pin. A first guide axis is arranged along the optical axis and allows the retractable lens frame to move in the optical axis direction, A biasing spring is provided in the retractable lens frame, biases the cam pin holder toward the subject in the optical axis direction, and extends and retracts when the teleconverter is mounted on the mounting part, causing the retractable lens frame to retract in the optical axis direction. A lens barrel equipped with this feature.

2. The cam pin is positioned in the same location relative to the cam frame before the teleconverter is installed and after the teleconverter is installed. The lens barrel according to claim 1.

3. The retractable lens frame is provided with a second guide axis that guides the movement of the cam pin holder in the optical axis direction, and a rotation restricting unit that restricts the rotation of the cam pin holder about the second guide axis as it moves along the second guide axis in the optical axis direction, The lens barrel according to claim 1 or 2.

4. The rotation restricting portion contacts the cam pin holder at both ends in the radial direction of a circle centered on the optical axis of the optical lens. The lens barrel according to claim 3.

5. The system further includes a substantially cylindrical fixing frame provided between the cam frame and the retractable lens frame, the cam pin holder having a through groove that is exposed to the cam frame side, The cam pin holder has a projection that engages with the through groove of the fixing frame to prevent the cam pin from falling out of the cam groove. The lens barrel according to claim 1 or 2.

6. The cam pin holder has an insertion hole into which the first guide shaft is inserted with a predetermined gap. The lens barrel according to claim 1 or 2.

7. The system further includes an attachment detection unit that detects when the teleconverter is attached to the attachment unit. The lens barrel according to claim 1 or 2.

8. The aforementioned mounting detection unit detects that the teleconverter has been mounted, and further includes a display control unit that controls a display unit provided on the camera body to display a message indicating that shooting is required, depending on the position of the optical lens held by the retractable lens frame. The lens barrel according to claim 7.

9. The first guide axis has a principal axis that guides the movement of the retractable lens frame in the optical axis direction, and a secondary axis that restricts the rotation of the retractable lens frame about the first guide axis. The lens barrel according to claim 1 or 2.

10. The biasing spring extends and retracts when the optical lens is near the WIDE position, causing the retractable lens frame to retract. The lens barrel according to claim 1 or 2.

11. The retractable lens frame is provided on the side to which the teleconverter is mounted, and further includes a cushioning member to reduce collision with the member on the teleconverter side. The lens barrel according to claim 1 or 2.

12. The retractable lens frame has a holding portion for holding the optical lens, When the teleconverter is installed, the retaining portion moves in a direction toward the cam pin holder as the biasing spring contracts. The lens barrel according to claim 1 or 2.

13. A lens barrel that is attached to the camera body in a replaceable manner, The mounting section to which the teleconverter is attached, When the teleconverter is attached, the retractable lens frame includes an optical lens that interferes in the optical axis direction, A rack that protrudes in a direction intersecting the optical axis and moves along the optical axis, A rack holder is provided on the retractable lens frame in a manner that allows relative movement in the optical axis direction, and holds the rack, A drive unit connected to the rack, which moves the retractable lens frame back and forth in the optical axis direction via the rack holder, A first guide axis is arranged along the optical axis and allows the retractable lens frame to move in the optical axis direction, A biasing spring is provided in the retractable lens frame, biases the rack holder toward the subject in the optical axis direction, and extends and retracts when the teleconverter is mounted on the mounting part, causing the retractable lens frame to retract in the optical axis direction. A lens barrel equipped with this feature.

14. A lens barrel according to claim 1 or 13, The camera body to which the aforementioned lens barrel is attached, A camera equipped with this.

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