Lens device

Abstract

To provide a lens device suitable for applying lubricant to sliding parts. [Solution] A lens device comprising a fixed cylinder, an optical system, and an operating ring having a sliding portion between the fixed cylinder and the sliding portion, wherein the operating ring rotates to move an optical element in the optical system, the operating ring having a hole and a groove at the position of the sliding portion, the hole being configured in a direction including a component perpendicular to the optical axis of the optical system, the groove being configured in a circumferential direction with respect to the optical axis, and at least a portion of the hole and the groove being in communication.

Description

Technical Field

[0001] The present invention relates to a lens device that drives an optical element by rotating an operation ring.

Background Art

[0002] Conventionally, lubricants have been applied to the sliding parts of the operation part and the fixed part of the lens device for the purpose of improving durability and torque adjustment. The lubricant is applied to the fixed part with an injection tool such as a dispenser or a syringe, and then the operation part is inserted into the fixed part from the optical axis direction to fill the sliding part with the lubricant. Patent Document 1 shows a typical structure of the sliding part of the lens device.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, when the above coating method is performed with the structure of Patent Document 1, the lubricant applied to the fixed part may be scraped out from the sliding part when the operation part is inserted, and the lubricant may not be sufficiently applied to the desired location. Furthermore, when attempting to apply lubricant during maintenance, the lens must be disassembled and the operation part removed in order to apply the lubricant.

[0005] One object of the present invention is to provide a lens device suitable for applying a lubricant to a sliding part.

Means for Solving the Problems

[0006] To achieve the above objective, an embodiment of the present invention provides a lens device comprising a fixed cylinder, an optical system, and an operating ring having a sliding portion between itself and the fixed cylinder and rotatably attached to the fixed cylinder via the sliding portion, wherein the optical elements in the optical system are moved by rotating the operating ring, the operating ring having a hole and a groove at the position of the sliding portion, the hole being configured in a direction including a component perpendicular to the optical axis of the optical system, the groove being configured in a circumferential direction with respect to the optical axis, and at least a portion of the hole and the groove being in communication. [Effects of the Invention]

[0007] According to the present invention, a lens device suitable for applying lubricant to sliding parts can be provided. [Brief explanation of the drawing]

[0008] [Figure 1] This is a cross-sectional view of the lens device in Embodiment 1. [Figure 2] This is a cross-sectional view of the operating section of the lens device in Embodiment 1. [Figure 3] This is an enlarged view of the area around the sliding part in Figure 2. [Figure 4] This is a cross-sectional view of the lens device in Embodiment 2. [Figure 5] This is a cross-sectional view of the lens device in Embodiment 3. [Figure 6] This is a cross-sectional view of the lens device in Embodiment 3. [Figure 7] This is a cross-sectional view of the lens device in Embodiment 4. [Figure 8] This is a cross-sectional view of the lens device in Embodiment 4. [Figure 9] This is a cross-sectional view of the lens device in Embodiment 5. [Figure 10] This is a cross-sectional view of the lens device in Embodiment 6. [Modes for carrying out the invention]

[0009] Embodiments of the present invention will be described below with reference to the drawings. However, the present invention is not limited to the following embodiments. In each drawing, the same reference numeral is used for the same member or element, and redundant explanations are omitted or simplified.

[0010] <Embodiment 1> The lens device in Embodiment 1 of the present invention will be described with reference to Figures 1 to 3. Figure 1 is a cross-sectional view of the lens device in Embodiment 1, Figure 2 is a cross-sectional view of the operating section of the lens device in Embodiment 1, and Figure 3 is an enlarged view of the area around the sliding section in Figure 2.

[0011] The first operating ring 2 is rotatably engaged with the fixed cylinder 1 around the optical axis of the lens, and its position in the optical axis direction (same direction as the optical axis) is restricted by the fixing member 3. The fixing member 3 is fixed to the fixed cylinder 1 by screws (not shown), for example, from a direction that includes a component perpendicular to the optical axis. That is, the fixing member 3 restricts the optical axis direction of the first operating ring 2 and is fixed to the fixed cylinder 1, restricting the movement of the operating ring in a direction that includes a component parallel to the optical axis, and fixing the operating ring to the fixed cylinder.

[0012] The second operating ring 4 is engaged with the fixed cylinder 1 so as to be rotatable around the optical axis. The cam cylinder 5 is engaged with the fixed cylinder 1 so as to be rotatable around the optical axis and is connected to the first operating ring 2. By rotating the first operating ring 2 using a drive structure consisting of a straight groove and a cam groove (not shown), the optical elements (lens, lens holder, aperture, etc.) can be manipulated, and the focal length can be varied. In other words, by rotating the operating ring, the optical elements in the optical system can be moved.

[0013] Sliding parts 10 and 11 are provided between the first operating ring 2 and the fixed cylinder 1 in the direction of the optical axis circumferentially. That is, the first operating ring 2 is rotatably attached to the fixed cylinder 1 via the sliding parts 10 and 11 and is slidable in the circumferential direction (around the optical axis, in the direction of the optical axis circumferentially).

[0014] Further, in the first operation ring 2, hole portions 6 and 7 in the direction perpendicular to the optical axis are provided at the positions of the sliding portions 10 and 11 in the circumferential direction of the optical axis, and grooves 8 and 9 are provided over the entire circumference in the circumferential direction of the optical axis. Note that the hole portions 6 and 7 do not have to be holes perpendicular to the optical axis, and may be holes in an oblique direction substantially toward the optical axis.

[0015] Note that, in FIGS. 1 to 3 and the like, the lubricant application effect is enhanced by providing grooves at the positions of the sliding portions 10 and 11 in the circumferential direction of the optical axis facing the grooves 8 and 9 over the entire circumference in the circumferential direction of the optical axis, but these grooves may be omitted.

[0016] Further, in the first operation ring 2, caps 12 and 13 as covers for closing the hole portions 6 and 7 are arranged. Here, FIG. 3 shows the relationship of the distances L1 to L3 from the optical axis of the lens to the hole portion 7, the groove 9, and the sliding portion 11 (the distance relationship is the same for the hole portion 6, the groove 8, and the sliding portion 10).

[0017] L1 is the distance from the optical axis of the lens to the sliding portion 11, L2 is the distance from the optical axis of the lens to the bottom (innermost diameter portion) of the hole portion 7, and L3 is the distance from the optical axis of the lens to the outermost diameter of the groove 9, and satisfies the following formula 1. L3 > L2 > L1 ··· (Formula 1)

[0018] That is, the distance L2 from the optical axis to the innermost diameter of the hole portion 7 is greater than the distance L1 from the optical axis to the sliding portion 11 and is not more than L3 which is the distance from the optical axis to the outermost diameter of the groove 9. In other words, the distance from the optical axis to the innermost diameter of the hole portion is longer than the distance from the optical axis to the sliding portion and is not more than the distance from the optical axis to the outermost diameter of the groove portion.

[0019] Note that the cross section of the groove 9 is triangular in FIG. 3, but it may not be triangular and may be, for example, trapezoidal or the like. In that case, L3 = L2 may be satisfied.

[0020] Next, a method for applying a lubricant in the structure of the present embodiment will be described. By removing the caps 12 and 13, access from the outside to the hole portions 6 and 7 can be achieved. The tip of an injection tool filled with a lubricant is inserted into the hole portions 6 and 7, and the lubricant is applied to the sliding portions 10 and 1 having the first operation ring 2 rotated in the circumferential direction of the optical axis at the same time.

[0021] Here, we will explain the effect when L1 to L3 satisfy the above formula 1. For example, even if holes 6 and 7 are through holes extending to sliding parts 10 and 11, lubricant can be applied to the sliding parts 10 and 11 from the outside. However, when the first operating ring 2 is rotated, the lubricant applied to the sliding parts 10 and 11 is scraped out by the cylindrical sides of holes 6 and 7.

[0022] Therefore, grooves 8 and 9 are provided in the first operating ring 2 in the circumferential direction of the optical axis, and the relationship between their distances from the optical axis satisfies the above equation 1. As a result, the holes 6 and 7 do not come into contact with the sliding parts 10 and 11, so that even when the first operating ring 2 is rotated, the lubricant is less likely to be scraped out from the cylindrical sides of the holes 6 and 7.

[0023] Furthermore, since holes 6 and 7 are in communication with grooves 8 and 9, lubricant injected from holes 6 and 7 is applied to the sliding parts 10 and 11 via grooves 8 and 9.

[0024] Thus, the operating ring of this embodiment has, at the position of the sliding portion, holes oriented toward at least one optical axis in the circumferential direction of the optical axis, and grooves in the circumferential direction of the optical axis, and is configured such that at least a portion of the holes and grooves in the circumferential direction of the optical axis are in communication.

[0025] Specifically, the operating ring has a hole and a groove at the position of the sliding part, the hole is configured in a direction that includes a component perpendicular to the optical axis of the optical system, and the groove is configured in a circumferential direction with respect to the optical axis, and at least a portion of the hole and the groove are in communication. Therefore, lubricant can be applied to the desired sliding parts 10 and 11 without disassembling the lens device.

[0026] Furthermore, since there is no need to disassemble the lens device, optical adjustments that were previously required each time lubricant was applied during maintenance are eliminated, improving work efficiency.

[0027] <Embodiment 2> Figure 4 is a cross-sectional view of the lens device in Embodiment 2. A sealing member 14 is inserted through the hole 7 of the first operating ring 2 to seal the hole 7. That is, the operating ring has a sealing member that seals the hole 7.

[0028] Furthermore, a gap is formed between the lower end of the sealing member 14 and the bottom of the hole 7. Although the hole 7 is described as an example, the structure of the hole 6 is similar. As a result, as shown in Figure 4, a lubricant reservoir 30 can be provided between the sliding part 11 and the sealing member 14. In other words, in this embodiment, there is a sealing member 14 that seals the hole, and a lubricant reservoir 30 for holding lubricant is provided near the tip of the hole.

[0029] The sealing member 14 may be, for example, a rubber cap, but it may also be a set screw. That is, the hole 7 may be threaded, and a set screw may be inserted through it. If it is then necessary to apply lubricant to the sliding part again, the set screw can be screwed in, pushing the lubricant out of the lubricant reservoir 30 and applied to the sliding part 11.

[0030] <Embodiment 3> In Embodiments 1 and 2, the first operating ring 2 and the fixing member 3 were in a structure where they did not overlap at the position of the sliding portion in the circumferential direction of the optical axis. However, in Embodiment 3, a structure in which they partially overlap will be described with reference to Figures 5 and 6.

[0031] Figure 5 is a cross-sectional view of the lens device in Embodiment 3, and Figure 6 is a cross-sectional view of the lens device in Embodiment 3. The fixing member 3 has a through hole 15 at the position of the sliding portion 11 in the circumferential direction of the optical axis, and is fixed to the fixing cylinder 1 from the direction perpendicular to the optical axis by a plurality of fixing portions 17 provided in the circumferential direction of the optical axis. Similar to Embodiment 1, the tip of an injection tool is inserted into the hole portion 7 through the through hole 15 in order to apply lubricant from the outside.

[0032] However, since the first operating ring 2 can rotate while the fixing member 3 is fixed to the fixing cylinder 1, it is not possible to apply lubricant to the circumferential direction of the sliding part 11 while rotating the first operating ring 2. Therefore, a through hole 16 in the optical axis direction is provided in the second operating ring 4 at the position of the fixing part of the optical axis direction fixing part 17.

[0033] In other words, the second operating ring is rotatably engaged with the fixed cylinder and has a through hole at the fixed part that is configured to include a component perpendicular to the optical axis, so that the fixed part 17 can be accessed from the outside without disassembling the lens device.

[0034] In other words, when applying lubricant, the fixing part 17 is released, allowing the fixing member 3 to rotate freely. The tip of the injection tool can then be inserted into the through hole 15 and the hole 7, and the lubricant can be applied to the sliding part 11 in the circumferential direction while rotating the first operating ring 2 and the fixing member 3 together. After applying the lubricant, the fixing part 17 is fixed again, restricting the movement of the first operating ring 2 in the optical axis direction once more.

[0035] With the above structure, even in a compact structure where the first operating ring 2 and the fixing member 3 overlap at the position of the optical axis circumferential sliding part 11, lubricant can be applied to the sliding part 11 without disassembling the lens device.

[0036] <Embodiment 4> In Embodiment 3, a structure was described in which the fixing member 3 is removed in order to apply lubricant. However, in Embodiment 4, an example of a structure in which the fixing member 3 is not removed will be described with reference to Figures 7 and 8.

[0037] Figure 7 is a cross-sectional view of the lens device in Embodiment 4, and Figure 8 is a cross-sectional view of the lens device in Embodiment 4. In Embodiment 4, the fixing member 3 is composed of a base portion 18 and a rotating portion 19.

[0038] The base portion 18 is fixed to the fixing cylinder 1 from a direction perpendicular to the optical axis by screws (not shown). The rotating portion 19 is rotatable relative to the base portion 18 in the direction circumferential to the optical axis and is fixed to the base portion 18 by a plurality of fixing portions 21 provided in the direction circumferential to the optical axis. That is, in Embodiment 4, the fixing member has a base portion fixed to the fixing cylinder and a rotating portion fixed to the base from a direction perpendicular to the optical axis. In other words, it has a rotating portion fixed to the base from a direction that includes a component perpendicular to the optical axis.

[0039] Furthermore, the rotating part 19 is provided with a through hole 20 at the position of the sliding part 11 in the circumferential direction of the optical axis. When applying lubricant to the sliding part 11, the rotating part 19 becomes rotatable relative to the base part 18 by releasing the fixing of the fixing part 21. The tip of the injection tool can be inserted through the through hole 20 and the hole 7, and the lubricant can be applied to the sliding part 11 in the circumferential direction while rotating the first operating ring 2 and the rotating part 19 together.

[0040] In other words, in Embodiment 4, the rotating part 19 has a through hole 20 at a position corresponding to the position of the hole 7 provided in the operating ring.

[0041] In Embodiment 4, the fixing member 3 is made into two parts, a base 18 and a rotating part 19, in order to apply lubricant to the sliding part. Therefore, lubricant can be applied to the sliding part 11 without removing the fixing member 3 and while maintaining the restriction of the optical axis direction of the first operating ring 2.

[0042] Furthermore, in the configuration of Embodiment 4, the first operating ring 2 is provided with, for example, a focal length indicator, and the rotating part 19 is provided with an indicator line, and the rotating part 19 is made rotatable, thereby allowing the indicator line to be adjusted relative to the indicator.

[0043] <Embodiment 5> Figure 9 is a cross-sectional view of the lens device in Embodiment 5. The relationship between the sliding area M1 of the sliding portion 10 where the first operating ring 2 and the fixing member 3 do not overlap in the optical axis direction and the sliding area M2 of the sliding portion 11 where they overlap is defined as M1 > M2.

[0044] In other words, in Embodiment 5, there are at least two or more sliding parts 10 and 11 spaced apart from each other between the fixed cylinder 1 and the operating ring 2 in the optical axis direction, and the sliding surfaces of the sliding parts 10 and 11 are different in size. That is, the operating ring has two or more sliding parts, and the sliding surfaces of the two or more sliding parts are different in size from each other.

[0045] In Embodiment 5, the sliding surface area is made different, and the sliding surface area of ​​the sliding part on the side to which lubricant can be applied is made larger, thereby increasing the contribution to torque. As a result, even when there is only one sliding part to which lubricant is applied, the same effect as when there are two can be obtained.

[0046] <Embodiment 6> Figure 10 is a cross-sectional view of the lens device in Embodiment 6. An electric drive device 50 for electrically driving the first operating ring 2 and the second operating ring 4 of Embodiments 1 to 5 is fixed to the fixed cylinder 1 of the lens device 40. In other words, an electric drive device for electrically driving the operating rings is attached to the fixed cylinder 1.

[0047] Here, the angle in the circumferential direction of the optical axis where the electric drive unit 50 overlaps with the lens device is defined as angle 60. The holes 6 and 7 are positioned within this angle 60 range. It is also possible that a part of the electric drive unit protrudes beyond the angle 60 and covers the holes 6 and 7 thereby. Thus, in Embodiment 6, the holes 6 and 7 provided in the operating ring are covered by a part of the electric drive unit. Therefore, the holes 6 and 7 are not visible externally.

[0048] Although the present invention has been described in detail above based on its preferred embodiments, the present invention is not limited to the above embodiments, and various modifications and combinations of the above embodiments are possible in accordance with the spirit of the present invention, and these are not excluded from the scope of the present invention. Furthermore, some of the above embodiments may be combined as appropriate.

[0049] (Configuration 1) A lens device comprising a fixed cylinder, an optical system, and an operating ring having a sliding portion between itself and the fixed cylinder and being rotatably attached to the fixed cylinder via the sliding portion, wherein the optical elements in the optical system are moved by rotating the operating ring, the operating ring having a hole and a groove at the position of the sliding portion, the hole being configured in a direction including a component perpendicular to the optical axis of the optical system, the groove being configured in a circumferential direction with respect to the optical axis, and at least a portion of the hole and the groove being in communication.

[0050] (Configuration 2) The lens device according to Configuration 1, characterized in that the distance from the optical axis to the innermost diameter of the hole is longer than the distance from the optical axis to the sliding portion and less than or equal to the distance from the optical axis to the outermost diameter of the groove.

[0051] (Configuration 3) The lens device according to Configuration 1 or 2, characterized in that the operating ring has two or more sliding parts, and the sliding surface areas of the two or more sliding parts are different from each other.

[0052] (Configuration 4) The lens device according to any one of Configurations 1 to 3, characterized in that the operating ring has a sealing member that seals the hole.

[0053] (Configuration 5) A lens device according to any one of Configurations 1 to 4, wherein the device has a fixing member that restricts the movement of the operating ring in a direction including a component parallel to the optical axis and fixes the operating ring to the fixing cylinder, the fixing member having a base fixed to the fixing cylinder and a rotating part fixed to the base from a direction including a component perpendicular to the optical axis, and the rotating part having a through hole at a position corresponding to the position of the hole.

[0054] (Configuration 6) A lens device according to any one of Configurations 1 to 5, characterized in that it has a fixing member that restricts the movement of the operating ring in a direction including a component parallel to the optical axis and fixes the operating ring to the fixing cylinder, the fixing member having a fixing portion fixed to the fixing cylinder from a direction including a component perpendicular to the optical axis, and a second operating ring that is rotatably engaged with the fixing cylinder and includes a through hole configured at the position of the fixing portion in a direction including a component perpendicular to the optical axis.

[0055] (Configuration 7) The lens device according to any one of Configurations 1 to 6, characterized in that a drive device for electrically driving the operating ring is attached to the fixed cylinder, and the hole is covered by a part of the drive device.

[0056] (Configuration 8) A lens device according to any one of Configurations 1 to 7, characterized by having a sealing member for sealing the hole and a lubricant reservoir for holding lubricant near the tip of the hole.

[0057] (Configuration 9) The lens device according to any one of Configurations 1 to 8, characterized in that the operating ring is slidable in the circumferential direction relative to the fixed cylinder via the sliding portion. [Explanation of Symbols]

[0058] 1: Fixed tube 2: 1st operation ring 3: Fixing member 6, 7: Hole 8, 9: Groove 10, 11: Sliding parts

Claims

1. Fixed cylinder and Optical system and It comprises an operating ring having a sliding portion between itself and the aforementioned fixed cylinder, and the operating ring being rotatably attached to the fixed cylinder via the sliding portion, In a lens device that moves an optical element in the optical system by rotating the aforementioned operating ring, The operating ring has a hole and a groove at the position of the sliding portion, The aforementioned hole is configured in a direction that includes a component perpendicular to the optical axis of the optical system, The groove portion is configured in the circumferential direction with respect to the optical axis, A lens device characterized in that at least a portion of the hole and the groove are in communication.

2. The lens device according to claim 1, characterized in that the distance from the optical axis to the innermost diameter of the hole is longer than the distance from the optical axis to the sliding portion and less than or equal to the distance from the optical axis to the outermost diameter of the groove.

3. The operating ring has two or more sliding parts, The lens device according to claim 1, characterized in that the sliding surfaces of the two or more sliding parts are different in size from each other.

4. The lens device according to claim 1, characterized in that the operating ring has a sealing member that seals the hole.

5. The operating ring has a fixing member that restricts the movement of the operating ring in a direction including a component parallel to the optical axis and fixes the operating ring to the fixing cylinder, The fixing member has a base that is fixed to the fixing cylinder and a rotating part that is fixed to the base from a direction that includes a component perpendicular to the optical axis. The lens device according to claim 1, characterized in that the rotating part has a through hole at a position corresponding to the position of the hole.

6. The operating ring has a fixing member that restricts the movement of the operating ring in a direction including a component parallel to the optical axis and fixes the operating ring to the fixing cylinder, The aforementioned fixing member is A fixing part fixed to the aforementioned fixing cylinder from a direction including a component perpendicular to the optical axis, The lens device according to claim 1, further comprising: a second operating ring that is rotatably engaged with the fixed cylinder and includes a through hole configured at the position of the fixed portion in a direction that includes a component perpendicular to the optical axis.

7. A drive device for electrically driving the operating ring is attached to the fixed cylinder. The lens device according to claim 1, characterized in that the hole is covered by a part of the drive device.

8. A sealing member for sealing the aforementioned hole, The lens device according to claim 1, characterized in that it has a lubricant reservoir for holding lubricant near the tip of the hole.

9. The lens device according to claim 1, characterized in that the operating ring is slidable in the circumferential direction relative to the fixed cylinder via the sliding portion.

Images