Lens barrel and knob anti-detachment member

Abstract

In order to prevent a fixing member from falling off, a knob drop-off prevention member switches between a state in which a knob can be attached to and detached from a lens barrel body and a state in which the knob cannot be attached to and detached from the lens barrel body. In addition, the knob may be an anti-drop screw that has a first body that is threaded, a second body that is smaller in diameter than the first body and not threaded, and a diameter greater than that of the second body but equal to or less than that of the first body. Further, an operating member may include a screw hole that can be screwed in by the first body of the knob, and the knob anti-drop member may include a daruma doll hole configured to connect a hole through which the third body of the knob can be inserted and a hole through which the third body cannot be inserted.

Description

Technical Field

[0001] The present invention relates to a lens barrel and a knob detachment prevention member.

Background Art

[0002] Conventionally, a camera lens barrel mounted on a camera is provided with members used for operations to adjust built-in focus functions and iris functions. Generally, in order to fix the positional relationship of the members after adjusting the focus function and iris function, a fixing member called a knob is used.

[0003] For example, in Patent Document 1, a fixing member is screwed onto a member used for an operation, and by pushing the tip of the fixing member into an inner member, the movement of the fixing member is restricted by the frictional force between the fixing member and the inner member, and as a result, a technique for fixing the member used for the operation is disclosed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the technique described in Patent Document 1, since the knob, which is a fixing member, is a screw-type fixing, it was possible to remove the knob itself by loosening the screw. Therefore, there was a risk that the knob would accidentally come off and fall off when adjusting the focus function and iris function. In addition, even when not adjusting the focus function and iris function, due to vibrations and impacts of environmental factors at the camera installation location being applied to the lens barrel, etc., the screw of the knob would loosen, and there was also a risk that the loosening would become large and the knob would fall off.

[0006] The present invention aims to provide a lens barrel that can prevent the fixing member from falling off. [Means for solving the problem]

[0007] The lens barrel according to the present invention comprises an operating member rotatably arranged in the circumferential direction relative to the lens barrel body, and a knob for restricting and fixing the rotation of the operating member in the circumferential direction, characterized in that it comprises a knob detachment prevention member that can switch between a first state in which the knob is detachable from the lens barrel body and a second state in which the knob is not detachable from the lens barrel body.

[0008] Furthermore, in the lens barrel according to the present invention, the knob is a screw that prevents it from falling off, comprising a first body portion that is threaded, a second body portion that is smaller in diameter than the first body portion and is not threaded, and a third body portion that is larger in diameter than the second body portion and has a diameter equal to or less than that of the first body portion, the operating member has a screw hole into which the first body portion of the knob can be screwed, and the knob fall prevention member has a keyhole formed by connecting a first hole through which the third body portion of the knob can be inserted and a second hole through which the third body portion cannot be inserted, and the first state and the second state are switched by changing the position of the keyhole relative to the second body portion of the knob.

[0009] Furthermore, in the lens barrel according to the present invention, the first hole and the second hole of the thumb-ring hole are configured to communicate in the circumferential direction with respect to the knob fall-off prevention member, the knob fall-off prevention member is arranged to be rotatable in the circumferential direction, and the first state and the second state are switched by rotating the position of the thumb-ring hole relative to the second body of the knob in the circumferential direction.

[0010] Furthermore, in the lens barrel according to the present invention, the first hole and the second hole of the thumb-removal member are configured to communicate axially with respect to the lens barrel body of the knob fall-off prevention member, the knob fall-off prevention member is arranged to be movable axially with respect to the lens barrel body, and the first state and the second state are switched by moving the position of the thumb-removal member with respect to the second body of the knob in the axial direction.

[0011] The knob anti-detachment member according to the present invention is a knob anti-detachment member that is attached to a lens barrel which comprises an operating member arranged to be circumferentially rotatable with respect to the lens barrel body and a knob for restricting and fixing the rotation of the operating member in the circumferential direction, and is characterized in that it is possible to switch between a first state in which the knob can be detached from the lens barrel body and a second state in which the knob cannot be detached from the lens barrel body. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a lens barrel that can prevent the fixing member from falling off. [Brief explanation of the drawing]

[0013] [Figure 1] This is an explanatory diagram illustrating an example of the external configuration of a lens barrel 100 corresponding to at least one embodiment of the present invention. [Figure 2] This is an explanatory diagram illustrating an example of the configurations of the screw hole forming portion 31, the knob fall prevention member 40, and the knob 50, corresponding to at least one embodiment of the present invention. [Figure 3] This is an explanatory diagram illustrating an example of switching between a first state and a second state using a knob fall prevention member 40 corresponding to at least one embodiment of the present invention. [Figure 4] This is an explanatory diagram illustrating an example of switching between a first state and a second state using a knob fall prevention member 40 corresponding to at least one embodiment of the present invention. [Figure 5]It is an explanatory diagram for explaining an example of preventing the knob 50 from falling off by the knob fall prevention member 40 corresponding to at least one of the embodiments of the present invention. [Figure 6] It is an explanatory diagram for explaining an example of preventing the knob 50 from falling off by the knob fall prevention member 40 corresponding to at least one of the embodiments of the present invention. [Figure 7] It is an explanatory diagram for explaining an example of the configuration of the second cylinder 70 and the knob fall prevention member 80 corresponding to at least one of the embodiments of the present invention. [Figure 8] It is an explanatory diagram for explaining an example of the configuration of the second cylinder 70 and the knob fall prevention member 80 corresponding to at least one of the embodiments of the present invention. [Figure 9] It is an explanatory diagram for explaining an example of the configurations of the second cylinder 230, the knob fall prevention member 240, and the knob 50 corresponding to at least one of the embodiments of the present invention. [Figure 10] It is an explanatory diagram for explaining an example of the mounting of the knob fall prevention member 240 corresponding to at least one of the embodiments of the present invention. [Figure 11] It is an explanatory diagram for explaining an example of the mounting of the knob fall prevention member 240 corresponding to at least one of the embodiments of the present invention. [Figure 12] It is an explanatory diagram for explaining an example of the mounting of the knob fall prevention member 240 corresponding to at least one of the embodiments of the present invention. [Figure 13] [[ID=二十四]]It is an explanatory diagram for explaining an example of the mounting of the knob fall prevention member 240 corresponding to at least one of the embodiments of the present invention. [Figure 14] It is an explanatory diagram for explaining an example of the mounting of the knob fall prevention member 240 corresponding to at least one of the embodiments of the present invention. [Figure 15] It is an explanatory diagram for explaining an example of preventing the knob 50 from falling off by the knob fall prevention member 240 corresponding to at least one of the embodiments of the present invention. [Figure 16] It is an explanatory diagram for explaining an example of the Daruma hole 343 corresponding to at least one of the embodiments of the present invention.

Embodiments of the Invention

[0014] Hereinafter, examples of embodiments of the present invention will be described with reference to the drawings. Note that various components in the examples of the embodiments described below can be appropriately combined as long as there is no contradiction. In addition, the description of the content described as an example of a certain embodiment may be omitted in other embodiments.

[0015] [First Embodiment] First, referring to FIG. 1, an example of a lens barrel 100 according to the first embodiment of the present invention will be described.

[0016] FIG. 1 is an explanatory diagram for explaining an example of the external configuration of a lens barrel 100 corresponding to at least one of the embodiments of the present invention.

[0017] The lens barrel 100 is configured to be detachable from a camera body (not shown) and can be exchanged according to the purpose of use. The lens barrel 100 includes a mount portion 10, a first cylinder 20, a second cylinder 30, a knob 50, and a lens hood 60.

[0018] The mount portion 10 has a function of attaching the lens barrel 100 to the camera body. For example, the mount portion 10 is attached to the camera body by screwing with the camera body. The configuration of the mount portion 10 is not particularly limited as long as the lens barrel 100 can be attached to the camera body. Note that a rear lens may be provided in the mount portion 10.

[0019] The first tube 20 is a component rotatably mounted on the outer circumference of the lens barrel 100. The first tube 20 functions as an operating component used for lens operations. The first tube 20 consists of a screw hole forming portion 21 and a first tube body portion 22. The first tube 20 rotates circumferentially as the screw hole forming portion 21 and the first tube body portion 22 work together, thereby adjusting the focus function and iris function. The screw hole forming portion 21 is provided on the mount portion 10 side of the first tube 20. The screw hole forming portion 21 may also be provided on the second tube 30 side of the first tube 20. The screw hole forming portion 21 has a screw hole that can be screwed into by a knob 50 (described later), and is fixed to a knob fall prevention member 40 (not shown in Figure 1) (described later) by the knob 50.

[0020] The second tube 30 is a component rotatably mounted on the outer circumference of the lens barrel 100. The second tube 30 functions as an operating component used for lens operations. The second tube 30 consists of a screw hole forming portion 31 and a second barrel portion 32. The screw hole forming portion 31 and the second barrel portion 32 work together to rotate the second tube 30 circumferentially, thereby adjusting the focus function and iris function. The screw hole forming portion 31 is provided on the first tube 20 side of the second tube 30. The screw hole forming portion 31 may also be provided on the lens hood 60 side of the second tube 30. The screw hole forming portion 31 has a screw hole that can be screwed into by a knob 50 (described later), and is fixed by the knob 50 to a knob fall prevention member 40 (not shown in Figure 1) (described later). An inner tube 90 (not shown in Figure 1) (described later) is arranged inside the first tube 20 and the second tube 30.

[0021] The knob 50 is a component for restricting and fixing the rotation of the screw hole forming portion 31 in the circumferential direction. The knob 50 is screwed into the screw hole of the screw hole forming portion 31 and its position relative to the inner cylinder 90 is fixed by pressing it against the inner cylinder 90. Then, by fixing the position of the knob 50 relative to the inner cylinder 90, the position of the screw hole forming portion 31 into which the knob 50 is screwed is also fixed relative to the inner cylinder 90. Details of the configuration of the knob 50 and the fixing method using the knob 50 will be described later.

[0022] The lens hood 60 is attached to the front of the second barrel 30 and has the function of blocking light from outside the shooting frame and preventing impacts and dirt from getting on the lens. A front element lens (not shown) may be installed at the front of the lens hood 60.

[0023] Next, with reference to Figures 2 to 4, an example of the configuration of the screw hole forming portion 31, the knob fall prevention member 40, and the knob 50 corresponding to at least one embodiment of the present invention will be described. Since the knob fall prevention member 40 and knob 50 for fixing the first cylinder 20 and the knob fall prevention member 40 and knob 50 for fixing the second cylinder 30 have substantially the same configuration, the following description will focus on the configuration of the knob fall prevention member 40 and knob 50 in the second cylinder 30.

[0024] Figure 2 is an explanatory diagram illustrating an example of the configurations of the screw hole forming portion 31, the knob fall prevention member 40, and the knob 50 corresponding to at least one embodiment of the present invention. Figure 2 shows the second cylinder 30, the knob fall prevention member 40, and the knob 50.

[0025] The knob 50 is a fall-prevention screw comprising a handle portion 51, a first body portion 52, a second body portion 53, and a third body portion 54. The handle portion 51 is a member for the operator to hold the knob 50 by pinching it. Preferably, the handle portion 51 has a larger diameter than the first body portion 52. The first body portion 52 is threaded. The second body portion 53 has a smaller diameter than the first body portion 52 and is not threaded. The third body portion 54 has a larger diameter than the second body portion 53 and a diameter smaller than or equal to that of the first body portion 52. The third body portion 54 may also be threaded.

[0026] As described above, the second cylinder 30 comprises a screw hole forming portion 31 and a second cylinder body portion 32.

[0027] The screw hole forming portion 31 is a member comprising an elongated hole 33 and a screw hole 34. In the example shown in Figure 2, the screw hole forming portion 31 is an annular member, but the shape of the screw hole forming portion 31 is not particularly limited. For example, the shape of the screw hole forming portion 31 may be a part of an annular shape or a rectangular parallelepiped shape.

[0028] The elongated hole 33 is a hole for fixing the second cylinder 30 and the knob fall prevention member 40. The shape of the elongated hole 33 is not particularly limited, but the length of the elongated hole 33 in the longitudinal direction is greater than or equal to the length of the dowel hole 43 described later. The reason for making it an elongated hole is to allow switching between the first state and the second state while the fixing screw described later is loosened but not completely removed. Any hole used to fix the second cylinder 30 and the knob fall prevention member 40 does not necessarily have to be an elongated hole.

[0029] The screw hole 34 is a hole into which the first body portion 52 of the knob 50 can be screwed. The screw hole 34 is also formed so that the second body portion 53 and the third body portion 54 can be inserted through it. In the example shown in Figure 2, three screw holes 34 of the same shape are formed.

[0030] The knob detachment prevention member 40 is a member that can switch between a first state in which the knob 50 can be detached from the lens barrel 100 body and a second state in which the knob 50 cannot be detached from the lens barrel 100 body. Here, making the knob 50 detachable means making it possible to remove the knob 50 by loosening the screw. Also, making the knob 50 non-detachable means making it impossible to remove the knob 50 even if the screw is loosened.

[0031] In the example shown in Figure 3, the knob fall prevention member 40 is a member having a main body portion 41, a screw hole 42, and a keyhole 43.

[0032] The main body portion 41 is connected to the outer circumference of the tip of the first cylinder 20 and is a component in which a screw hole 42 and a keyhole 43 are formed. Here, the main body portion 41 is an annular member, and the portion of the main body portion 41 in which the screw hole 42 and keyhole 43 are formed can be housed inside the screw hole forming portion 31. That is, the portion of the main body portion 41 in question has a smaller diameter than the screw hole forming portion 31.

[0033] The screw hole 42 is a screw hole for fixing the second cylinder 30 and the knob anti-drop member 40. The screw hole 42 has a screw groove formed on its inner circumference that corresponds to the fixing screw. The diameter of the screw hole 42 is less than or equal to the length of the elongated hole 33 in the shorter direction. Note that the method of fixing the second cylinder 30 and the knob anti-drop member 40 is not limited to the fixing method using the screw hole 42.

[0034] The Daruma hole 43 is a hole formed by connecting the first hole 44 and the second hole 45. The first hole 44 is a hole through which the third body portion 54 of the knob 50 can be inserted. The second hole 45 is a hole through which the third body portion 54 of the knob 50 cannot be inserted. The knob fall prevention member 40 switches between the first state and the second state by changing the position of the Daruma hole 43 relative to the second body portion 53 of the knob 50. The shape of the first hole 44 is not particularly limited as long as the third body portion 54 of the knob 50 can be inserted. The shape of the second hole 45 is not particularly limited as long as the third body portion 54 of the knob 50 cannot be inserted.

[0035] In the example shown in Figure 2, three identically shaped thumbholes 43 are formed. Here, any combination of one screw hole 34 and one thumbhole 43 is used to fix the second barrel 30 and prevent the knob 50 from falling off. In this way, the formation of multiple screw holes 34 and multiple thumbholes 43 makes it easier to adjust the lens barrel 100 compared to the case where only one screw hole 34 and one thumbhole 43 are formed, even when it is difficult to change the orientation of the lens barrel 100 during adjustment, as any of the multiple screw holes 34 and multiple thumbholes 43 can be used.

[0036] The above describes an example of the configuration of the screw hole forming section 31, the knob fall prevention member 40, and the knob 50. Next, with reference to Figures 3 to 6, an example of switching between the first state and the second state using the knob fall prevention member 40 will be described.

[0037] Figures 3 and 4 are explanatory diagrams illustrating an example of switching between a first state and a second state by a knob fall prevention member 40 corresponding to at least one embodiment of the present invention. Hereinafter, the direction perpendicular to the central axis of the lens barrel 100 will be referred to as the vertical direction.

[0038] Figure 3 shows a state in which the positions of the second cylinder 30 and the knob anti-drop member 40 are offset axially relative to the lens barrel 100 for illustrative purposes. As shown in Figure 3, the position of the thumbtack hole 43 relative to the screw hole 34 changes by rotating the knob anti-drop member 40 in the circumferential direction of the lens barrel 100.

[0039] Figure 4 shows the knob anti-detachment member 40 attached to the second barrel 30. As shown in Figure 4, when using the lens barrel 100, the knob anti-detachment member 40 is attached to the inside of the screw hole forming portion 31 (positioned inside the second barrel 30). Furthermore, the knob anti-detachment member 40 and the screw hole forming portion 31 are adjusted so that both the screw hole 34 and the thumbscrew hole 43 are positioned outward from the approximate center of the lens barrel 100. That is, the screw hole 34 is adjusted to be positioned perpendicular to the thumbscrew hole 43.

[0040] The knob anti-detachment member 40 is rotatable relative to the second barrel 30 in the circumferential direction of the lens barrel 100 body by the length of the elongated hole 33. Also, when the knob 50 is inserted through the thumb-operated hole 43, the rotation of the knob anti-detachment member 40 causes the position of the thumb-operated hole 43 relative to the second barrel portion 53 of the knob 50 to rotate in the circumferential direction of the lens barrel 100 body. The screw hole 34 can be located perpendicular to the first hole 44, as shown in Figure 4(A), or perpendicular to the second hole 45, as shown in Figure 4(B). Here, the state shown in Figure 4(A) is the first state, and the state shown in Figure 4(B) is the second state.

[0041] Figures 5 and 6 are explanatory diagrams illustrating an example of preventing the knob 50 from falling off using a knob fall prevention member 40 corresponding to at least one embodiment of the present invention. Figures 5 and 6 show cross-sectional views of the screw hole forming portion 31 and the knob fall prevention member 40.

[0042] Figure 5(A) corresponds to Figure 4(A), where the screw hole 34 is located vertically to the first hole 44. The first hole 44 is a hole through which the third body portion 54 of the knob 50 can be inserted. Figure 5(B) corresponds to Figure 4(B), where the screw hole 34 is located vertically to the second hole 45. The second hole 45 is a hole through which the third body portion 54 of the knob 50 cannot be inserted.

[0043] Figure 6(A) is a cross-sectional view corresponding to Figure 5(A). The knob 50 is inserted through the screw hole 34 and the first hole 44. Since the screw hole 34 can accommodate the first body portion 52, the second body portion 53, and the third body portion 54, it is possible to insert the knob 50 to a position where it contacts the inner cylinder 90.

[0044] Figure 6(B) corresponds to Figure 5(B) and is a cross-sectional view showing the state in which the knob anti-detachment member 40 has been rotated circumferentially relative to the second cylinder 30 from the state shown in Figure 6(A). Specifically, the knob anti-detachment member 40 rotates circumferentially relative to the second cylinder 30 in the direction of the lens barrel 100 by moving, for example, the fixing screw that is screwed into the elongated hole 33 of the second cylinder 30 and the screw hole 42 of the knob anti-detachment member 40 by an operator. As mentioned above, the knob anti-detachment member 40 is fixed by the fixing screw used in the screw hole 42. When rotating the knob anti-detachment member 40, the fixing screw, which is looser than when the knob anti-detachment member 40 is fixed, is moved.

[0045] In Figure 6(B), the knob 50 is inserted through the screw hole 34 and the second hole 45. Here, the second hole 45 is a hole through which the third body portion 54 cannot be inserted, so the knob 50 cannot be removed. Therefore, when adjusting the focus function or iris function, it is possible to prevent the knob 50 from falling off when the screw on the knob 50 becomes loose, and also to prevent the screw on the knob 50 from becoming loose in the first place.

[0046] Furthermore, by screwing the knob 50 into place and pressing it against the inner cylinder 90, the frictional force between the third body 54 of the knob 50 and the inner cylinder 90 fixes (locks) the second cylinder 30 to the inner cylinder 90 (i.e., the main body of the lens barrel 100).

[0047] Furthermore, after inserting the knob 50, the knob anti-detachment member 40 is slid to switch to the second state, and then the fixing screw is screwed into the screw hole 42, thereby fixing the positional relationship between the second cylinder 30 and the knob anti-detachment member 40. In other words, the second state of the knob anti-detachment member 40 is maintained. By locking the second cylinder 30 and the knob anti-detachment member 40 in this way, it becomes possible to adjust the focus function, iris function, etc., while preventing the knob 50 from falling out.

[0048] As described above, in one aspect of the embodiment of the present invention, the lens barrel 100 comprises an operating member arranged to be circumferentially rotatable with respect to the lens barrel body, and a knob 50 for restricting and fixing the circumferential rotation of the operating member, and is equipped with a knob detachment prevention member 40 that can switch between a first state in which the knob 50 is detachable from the lens barrel body and a second state in which the knob 50 is not detachable from the lens barrel body, thereby preventing the fixing member from falling off.

[0049] Furthermore, in the lens barrel 100 according to the present invention, the knob 50 is a screw that prevents the knob from falling off, comprising a first body portion 52 which is threaded, a second body portion 53 which has a smaller diameter than the first body portion 52 and is not threaded, and a third body portion 54 which has a larger diameter than the second body portion 53 and a diameter equal to or less than that of the first body portion 52. The operating member has a screw hole 34 which can be screwed into by the first body portion 52 of the knob 50. The knob fall prevention member 40 has a thumbhole 43 which is formed by connecting a first hole 44 through which the third body portion 54 of the knob 50 can be inserted and a second hole 45 through which the third body portion 54 cannot be inserted. By changing the position of the thumbhole 43 relative to the second body portion 53 of the knob 50, it becomes possible to easily switch between a detachable state and a non-detachable state of the knob 50.

[0050] Furthermore, in the lens barrel 100, the first hole 44 and the second hole 45 of the thumb restraint member 40 are configured to communicate circumferentially with each other, and the thumb restraint member 40 is rotatable circumferentially. By rotating the position of the thumb restraint hole 43 relative to the second body portion 53 of the knob 50 in the circumferential direction, it becomes possible to switch between the first and second states using the same movement as the operation by the operating member.

[0051] Furthermore, if the lens barrel 100 is further equipped with an operating member that is circumferentially rotatable relative to the lens barrel body and a knob 50 for restricting and fixing the circumferential rotation of the operating member, and the knob anti-detachment member 40 attached to the lens barrel 100 is configured to switch between a first state in which the knob 50 can be detached from the lens barrel body and a second state in which the knob 50 cannot be detached from the lens barrel body, then it is possible to prevent the fixing member from falling off.

[0052] In the example described above, the knob fall prevention member 40 was configured such that the first hole 44 and the second hole 45 of the thumb-removal hole 43 communicated in the circumferential direction of the lens barrel 100 body. However, the orientation in which the thumb-removal hole is formed is not limited to this example. Below, a modified example of the knob fall prevention member will be described with reference to Figures 7 and 8. Note that the same parts as those described in Figures 1 to 6 will be omitted from the description.

[0053] Figures 7 and 8 are explanatory diagrams illustrating an example of the configuration of the second cylinder 70 and the knob fall prevention member 80 corresponding to at least one embodiment of the present invention. Compared with the knob fall prevention member 40 described in Figures 1 to 6, the example shown in Figures 7 and 8 has a different direction of movement of the knob fall prevention member when switching between the first state and the second state.

[0054] The screw hole forming portion 71 and screw hole 74 of the second tube 70 correspond to the screw hole forming portion 31 and screw hole 34, respectively. The main body portion 81, screw hole 82 (not shown) and thumbhole 83 of the knob fall prevention member 80 correspond to the main body portion 41, screw hole 42 and thumbhole 43, respectively. As shown in Figure 7, the thumbhole 83 is configured such that the first hole 84 and the second hole 85 communicate axially with the main body of the lens barrel in the knob fall prevention member 80.

[0055] Figures 8(A) and 8(B) show the second cylinder 70 and the knob anti-detachment member 80 in the first state. In Figure 8(A), the screw hole 74 is located perpendicular to the first hole 84. In Figure 8(B), the screw hole 74 is located perpendicular to the second hole 85. In the state of Figure 8(A), the knob anti-detachment member 80 moves in the direction relative to the second cylinder body 72, resulting in the state of Figure 8(B).

[0056] Thus, in the lens barrel 100, the locking hole 83 is configured such that the first hole 84 and the second hole 85 communicate axially with the lens barrel body of the knob fall prevention member 80, and the knob fall prevention member 80 is arranged to be movable axially with respect to the lens barrel body. By switching between the first state and the second state by moving the position of the locking hole 83 relative to the second barrel portion 53 of the knob 50 in the axial direction, the operation by the operating member and the operation of switching between the first state and the second state are in different directions, thus preventing accidental operation.

[0057] [Second Embodiment] Hereinafter, an example of a lens barrel 200 according to a second embodiment of the present invention will be described with reference to Figures 9 to 15. For components that are denoted by the same reference numerals as in the first embodiment, detailed descriptions of components that are the same as those described in the first embodiment will be omitted. In this second embodiment, the second barrel 230 and the knob fall prevention member 240 of the lens barrel 200 are each provided with screwed portions that can be screwed into each other. The second barrel 230 and the knob fall prevention member 240 are connected by the screwed portions of both.

[0058] Figure 9 is an explanatory diagram illustrating an example of the configurations of the second cylinder 230, the knob fall prevention member 240, and the knob 50 corresponding to at least one embodiment of the present invention. Figure 9 shows the second cylinder 230, the knob fall prevention member 240, and the knob 250.

[0059] The second cylinder 230 comprises a screw hole forming portion 231 and a second cylinder body portion 32. The screw hole forming portion 231 has a threaded portion 235 on its inner circumferential surface. The threaded portion 235 is formed on the inner circumferential surface of the screw hole forming portion 231 and screws into the knob anti-detachment member 240, which will be described later. In the following description, the process of rotating the knob anti-detachment member 240 clockwise to tighten the threaded portion 246 against the threaded portion 235 of the second cylinder 230, as viewed from the knob anti-detachment member 240 side, is referred to as "tightening the screw".

[0060] The knob fall prevention member 240 comprises a main body portion 241, a screw hole 42, a keyhole hole 243, and a threaded portion 246. The threaded portion 246 is formed on the outer circumferential surface of the main body portion 241 on the side facing the first cylinder 20. The threaded portion 246 is screwed into the threaded portion 235 of the second cylinder 230. The keyhole hole 243 is a hole formed by connecting the first hole 244 and the second hole 245. The first hole 244 is a hole through which the third body portion 54 of the knob 50 can be inserted. The second hole 245 has a larger diameter than the second body portion 53 of the knob 50, but is too small for the third body portion 54 to be inserted.

[0061] Here, the screw hole 34 and the thumbhole 243 are located on approximately the same circumferential line with respect to the lens barrel 200 when the second cylinder 230 and the knob fall prevention member 240 are screwed together by the screw portions 235 and 246.

[0062] Figures 10 to 14 are explanatory diagrams illustrating an example of mounting the knob fall prevention member 240 corresponding to at least one embodiment of the present invention. Hereinafter, the direction perpendicular to the central axis of the lens barrel 200 will be referred to as the vertical direction.

[0063] In Figure 10, the second cylinder 230 and the knob fall prevention member 240 are in the state of being tightened with screws. By tightening the screws, the screw hole 34 is adjusted to be vertically aligned with the keyhole 243. Figure 11 shows the state when the screws are fully tightened. In this state, the screw hole 34 is vertically aligned with the second hole 245.

[0064] Figure 12 shows the state in which the screw hole 34 is positioned vertically to the second hole 245. The state shown in Figure 12 is the state in which the screw has been adjusted by slightly loosening the screw from the state in Figure 11, where the screw has been fully tightened, so that the screw hole 34 is positioned vertically to the second hole 245. In other words, the state shown in Figure 12 is the state in which the screw has not been fully tightened. Figure 13 shows the state in Figure 12, with the knob 50 inserted through the screw hole 34 and the second hole 245 of the thumbscrew hole 243.

[0065] Figure 14 shows the state in which the screw hole 34 is positioned perpendicular to the first hole 244 of the keyhole hole 243, preventing the knob 50 from falling off. Figure 14 shows the state in Figure 13 when the screw is fully tightened. When the screw is tightened from the state in Figure 13, the second hole 245 fits into the second body portion 53 of the knob 50 with some play. Then, when the screw is tightened all the way, the second hole 245 is fixed in place in the second body portion 53 of the knob 50. In this state, even if the knob 50 is loosened, the third body portion 54 cannot pass through the second hole 245, so the knob 50 cannot be removed.

[0066] Figure 15 is an explanatory diagram illustrating an example of preventing the knob 50 from falling off using a knob fall prevention member 240 corresponding to at least one embodiment of the present invention. Figure 15 shows cross-sectional views of the screw hole forming portion 231 and the knob fall prevention member 240. Figure 15(A) corresponds to Figure 13, where the screw hole 34 is located perpendicular to the first hole 244. Figure 15(B) corresponds to Figure 13, where the screw hole 34 is located perpendicular to the second hole 245. In other words, the state in Figure 15(A) is the first state, and the state in Figure 15(B) is the second state. As shown in Figures 15(A) and 15(B), the second cylinder 230 and the knob fall prevention member 240 are screwed together by their respective screw portions 235 and 246.

[0067] Thus, in the lens barrel 200, the second barrel 230 and the knob anti-detachment member 240 are equipped with screw parts that can be screwed together. When the screw is tightened, the second hole 245 fits with a slight amount of play into the second body portion 53 of the knob 50. As a result, even if the knob 50 is loosened, the third body portion 54 cannot pass through the second hole 245. Therefore, the connection between the second barrel 230 and the knob anti-detachment member 240 and the state in which the knob 50 is prevented from falling off can be maintained.

[0068] The length of the second hole 245 can be anything, but it is preferable to give it a certain length so that it can maintain a state of preventing the screw from falling out even if it loosens slightly. By forming the second hole 245 with a length that can maintain a state of preventing the screw from falling out even if it loosens slightly, it is possible to prevent the knob 50 from being inserted through the first hole 344, and as a result it becomes possible to more reliably prevent the knob 50 from falling out of the lens barrel 300 body.

[0069] [Third Embodiment] The knob detachment prevention member used in the first and second embodiments is rotatable to switch between states. The fact that it can be switched means that there remains a risk that the knob detachment prevention member will be in the first state and the knob 50 will detach. Therefore, the second cylinder and the knob detachment prevention member may be fixed together to prevent the knob from detaching. The fixing of the second cylinder and the knob detachment prevention member will be described below using the second embodiment as an example.

[0070] Hereinafter, an example of a lens barrel 300 according to a third embodiment of the present invention will be described with reference to Figure 16. This third embodiment shares the basic structure with the second embodiment, but is an embodiment that is further equipped with a fixing structure. With regard to components that are denoted by the same reference numerals as in the second embodiment, detailed descriptions of components that are the same as those described in the second embodiment will be omitted. In the following description, the direction perpendicular to the central axis of the lens barrel 300 will be referred to as the vertical direction.

[0071] Figure 16 is an explanatory diagram illustrating an example of a thumbhole 343 corresponding to at least one embodiment of the present invention. In this third embodiment, the knob fall prevention member 340 of the lens barrel 300 has a thumbhole 343 formed by connecting a first hole 344, a second hole 345, and a third hole 346.

[0072] Figure 16(A) shows the Daruma hole 343. The first hole 344 and the second hole 345 correspond to the first hole 44 and the second hole 45 in the first embodiment and the first hole 244 and the second hole 245 in the second embodiment.

[0073] The third hole 346 is a hole that communicates with the first hole 344 and is formed in a position opposite the second hole 345 via the first hole 344. The third hole 346 is formed so that a predetermined member can be inserted into it. The predetermined member is, for example, a screw.

[0074] Figures 16(B) and 16(C) are explanatory diagrams illustrating an example of preventing the knob 50 from falling off using the knob fall prevention member 340, and are cross-sectional views of the AA' plane shown in Figure 16(A). Figure 16(B) shows the knob 50 fixed in place with the second holes 345 fitted into the second body portion 53, similar to the state in the second embodiment where the screw is fully tightened. In addition, a screw hole 334 is formed in the screw hole forming portion 331, separate from the screw hole 34 for inserting the knob 50. In Figure 16(B), the screw hole 334 is located vertically to the third hole 346.

[0075] In Figure 16(C), a screw 350 is screwed into the screw hole 334 and the third hole 346. The screw 350 is an example of a predetermined component. In the state shown in Figure 16(C), the positional relationship between the second cylinder 330 and the knob fall prevention member 340 is fixed by the screw 350 and cannot be loosened, so the position of the knob 50 relative to the keyhole 343 is fixed.

[0076] Thus, in the lens barrel 300, if the knob fall prevention member 340 has a dome-shaped hole 343 formed by connecting the first hole 344, the second hole 345, and the third hole 346, the fixed state between the second barrel 330 and the knob fall prevention member 340 can be maintained, and the positional relationship of the knob 50 to the dome-shaped hole 343 can be maintained, thereby preventing the knob fall prevention member 340 from returning to the first state, and as a result, it becomes possible to reliably prevent the knob 50 from falling off the lens barrel 300 body.

[0077] In the above description, the third hole 346 was a hole communicating with the second hole 345. However, the position in which the third hole 346 is formed is not limited to this, as long as the third hole can communicate with the screw hole 334 when the screw hole 34 and the second hole 345 are communicating. For example, the third hole may be formed at a position away from the second hole 345 and not communicating with it. Even if the third hole 346 is formed at a position away from the second hole 345, the second cylinder 330 and the knob anti-detachment member 340 will be fixed to the screw hole 334, thus reliably preventing the knob 50 from falling off the lens barrel 300 body. Furthermore, the method of fixing the predetermined member is not limited to screwing the member in place. An example of another method is to fix the predetermined member to the second cylinder 330 and the knob anti-detachment member 340 with an adhesive or the like to maintain the state in which it is inserted into the third hole 346. [Explanation of symbols]

[0078] 100, 200, 300 lens barrels 10 Mounting section 20. First tube (operating component) 21 Screw hole forming section 22 1st cylinder body 30, 70, 230, 330 Second cylinder (operating component) 31, 71, 231, 331 Screw hole forming section 32, 72 Second cylinder body 33, 73 Slotted holes 34, 42, 82, 334 screw holes 40, 80, 240, 340 Knob fall prevention component 41, 81, 241, 341 Main body 43, 83, 243, 343 Daruma holes 44, 84, 244, 344 First hole 45, 85, 245, 345 Second hole 235, 246 Screw part 346 Third Hole 350 screws 50 Knobs 51 Handle part 52 First fuselage 53 Second fuselage 54 Third Fuselage Section 60 Lens Hood 90 Inner cylinder

Claims

1. An operating member is positioned so as to be rotatable in the circumferential direction relative to the main body of the telescope tube, A knob for restricting and fixing the rotation of the aforementioned operating member in the circumferential direction, A lens barrel comprising, The knob is provided with a knob fall prevention member that can switch between a first state in which the knob is detachable from the lens barrel body and a second state in which the knob is not detachable from the lens barrel body. The knob is a fall-prevention screw comprising a first body portion that is threaded, a second body portion that is smaller in diameter than the first body portion and is not threaded, and a third body portion that is larger in diameter than the second body portion and has a diameter equal to or less than that of the first body portion. The operating member is provided with a screw hole into which the first body of the knob can be screwed, The knob fall prevention member is, The knob has a daruma-shaped hole formed by connecting a first hole through which the third body portion can be inserted and a second hole through which the third body portion cannot be inserted. The first state and the second state are switched by changing the position of the keyhole on the second body of the knob. A lens barrel characterized by the following features.

2. The aforementioned Daruma hole is configured such that the first hole and the second hole communicate in the circumferential direction of the knob fall prevention member. The knob fall prevention member is, The above-mentioned arrangement is rotatable in the circumferential direction, The first state and the second state are switched by rotating the position of the keyhole on the second body of the knob in the circumferential direction. The lens barrel according to feature 1.

3. The aforementioned Daruma hole is configured such that the first hole and the second hole communicate axially with respect to the lens barrel body of the knob fall prevention member. The knob fall prevention member is, The lens barrel body is arranged to be movable in the axial direction, The first state and the second state are switched by moving the position of the keyhole on the second body of the knob in the axial direction. The lens barrel according to feature 1.

4. It comprises an operating member that is rotatable in the circumferential direction relative to the main body of the lens barrel, and a knob for restricting and fixing the rotation of the operating member in the circumferential direction. The operating member is provided with a screw hole into which the first body portion of the knob can be screwed, The knob is a screw designed to prevent detachment, comprising a first body that is threaded, a second body that is smaller in diameter than the first body and is not threaded, and a third body that is larger in diameter than the second body and has a diameter equal to or less than that of the first body. A knob-removal prevention member that is attached to the lens barrel, The knob can be switched between a first state in which it is detachable from the main body of the telescope tube, and a second state in which it is not detachable from the main body of the telescope tube. The knob has a daruma-shaped hole formed by connecting a first hole through which the third body portion can be inserted and a second hole through which the third body portion cannot be inserted. The first state and the second state are switched by changing the position of the keyhole on the second body of the knob. A knob detachment prevention member characterized by the above.

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