JP6746909B2 - Lens barrel and optical equipment - Google Patents

Description

The present invention relates to a lens barrel and an optical device.

Conventionally, as an interchangeable lens of an interchangeable lens type camera, a demand for a zoom lens is high. In addition, the zoom lens has a problem that its total length becomes long in order to realize a high zoom ratio. For such a problem, for example, a zoom lens described in Patent Document 1 has been proposed (see Patent Document 1).
In Example 2 of Patent Document 1, the fourth group lens and the sixth group lens are integrally moved, and the fifth group lens between them is moved independently of the fourth group lens and the sixth group lens. Have been described.

JP-A-4-146407

A first aspect of the present invention includes a tubular first holding portion that holds a first lens, a second holding portion that holds a second lens and is connected to the first holding portion, and the first lens. And a second lens that holds a third lens disposed between the second lens and the second lens, and a cylindrical third holding portion that extends in the optical axis direction on the outer peripheral side of the first holding portion. The part has an insertion part through which the third holding part penetrates to the outer peripheral side of the first holding part between the second holding part, and the first holding part extends along the third holding part. Is movable in the optical axis direction, one of the concave groove or the convex groove is formed on the outer circumference of the first holding portion, and the other of the concave groove or the convex groove is formed on the inner circumference of the third holding portion, The present invention relates to a lens barrel in which the concave groove and the convex groove are fitted to each other.
A second invention is a tubular first holding portion that holds the first lens, a second holding portion that holds the second lens and is connected to the first holding portion, and the first lens. A cylindrical third holding portion that holds a third lens disposed between the second lens and the second lens, and extends on the outer peripheral side of the first holding portion in the optical axis direction. The holding part has an insertion part through which the third holding part penetrates to the outer peripheral side of the first holding part between the second holding part and the first holding part along the third holding part. A first cam follower is provided on the outer circumference of the second holding portion, a third cam follower is provided on the outer circumference of the third holding portion, and the first cam follower is fitted to the first cam follower. The present invention relates to a lens barrel having an operating ring provided with a cam groove and a third cam groove into which the third cam follower fits, on the outer peripheral side of the first holding portion.
A third aspect of the present invention is arranged between the first lens and the second lens, which is a tubular first holding member that holds the first lens and the second lens and has a first engaging portion on the outer peripheral side. A cylindrical second holding member that holds a third lens that is held, and that has a second engaging portion that engages with the first engaging portion on the inner peripheral side, and the first holding member is The present invention relates to a lens barrel that is movable in the optical axis direction with respect to a second holding member.
A fourth invention includes a tubular first member that holds the first lens and the second lens and has a first follower, and a third lens that is arranged between the first lens and the second lens. A tubular second member that holds the second follower and extends in the optical axis direction on the outer peripheral side of the first member; a first cam groove that engages with the first follower; and a second follower. A second cam groove that engages, and an operation ring that is arranged on the outer peripheral side of the first member and the second member , wherein the first member is an optical ring along the second member. Ru movable der axially, a lens barrel.
A fifth invention relates to an optical device including the lens barrel.

3A and 3B are schematic cross-sectional views of the main part of the lens barrel 1, in which FIG. 1A shows a wide state and FIG. 3 is an exploded perspective view of the lens barrel 1. FIG. It is a perspective view of a state before the second group cylinder 22 and the fourth group lens frame 25 are connected. It is a perspective view of the third group cylinder 23, (a) is a view seen from the subject side in the optical axis direction, (b) is a view seen from the camera body side in the optical axis direction. It is a perspective view of the first group cylinder 21. FIG. 3 is a development view of a fixed barrel 12 and a zoom operation ring 11. It is a schematic sectional drawing of the principal part of the lens barrel 1A of the comparison form of this embodiment corresponding to FIG. 1, (a) shows a wide state, (b) shows a tele state.

Hereinafter, embodiments of the present invention will be described with reference to the drawings and the like.
1A and 1B are schematic cross-sectional views of the main part of the lens barrel 1, where FIG. 1A shows a wide state and FIG. 1B shows a telephoto state. The lens barrel 1 is attachable to and detachable from the camera body 2 shown by the dotted line in FIG. 1A, but the present invention is not limited to this, and the lens barrel 1 and the camera body may be integrated. FIG. 2 is an exploded perspective view of the lens barrel 1, and the description of the lens group is omitted.

The lens barrel 1 includes a first lens group L1, a second lens group L2, a third lens group L3, and a fourth lens group L4 from the object side in the optical axis OA direction. Further, the lens barrel 1 includes a zoom operation ring 11 and a fixed barrel 12 from the outer peripheral side. A lens side mount 13 is fixed to the fixed barrel 12.
The lens barrel 1 further includes a first group barrel 21 that holds the first lens group L1, a third group barrel 23 that holds the third lens group L3, a second group barrel 22 and a fourth group barrel 22 that holds the second lens group L2. And a fourth group lens frame 25 that holds the lens group L4. The fourth group lens frame 25 is connected to the second group tube 22.

The 2-4 group cylinder 24 is formed by connecting the 2nd group cylinder 22 and the 4th group lens frame 25, and a perspective view of the state before the connection is shown in FIG.
On the outside of the fourth group lens frame 25, the second-fourth group cam followers 31 are formed at three substantially equal positions in the circumferential direction.
On the outer periphery of the second group cylinder 22, there are formed second to fourth group convex grooves 32 extending in the optical axis OA direction at three substantially equal circumferential positions. On the both sides of each 2-4 group convex groove 32, a slightly depressed 2-4 group concave groove 33 is formed. Further, in the 2-4 group cylinder 24, the 3rd group insertion portion 34 is formed between the 2nd group cylinder 22 and the 4th group lens frame 25 (illustrated in FIG. 1 ).

4A and 4B are perspective views of the third group cylinder 23. FIG. 4A is a view seen from the object side in the optical axis direction, and FIG. 4B is a view seen from the camera body side in the optical axis direction. Third-group cam followers 41 are formed at three substantially equal circumferential positions on the outer periphery of the end of the third-group barrel 23 on the camera body side.

The third group cylinder 23 has a tubular portion 46 and a lens holding portion 47 (the lens holding portion 47 is shown in FIG. 1). The third lens group L3 is arranged between the second lens group L2 and the fourth lens group L4.
The lens holding portion 47 that holds the third lens group L3 includes a third group holding ring 47b that holds the third lens group L3, and a first extending portion 47a that extends from the outer peripheral side toward the inner circumference of the tubular portion 46. And have. The first extending portion 47a penetrates the third group insertion portion 34 of the 2-4 group tube 24 and extends to the outer peripheral side. The tubular portion 46 extends toward the subject side in the optical axis OA direction from the tip of the first extending portion 47a extending to the outer peripheral side.
As shown in FIG. 2, the third group insertion portion 34 is formed by cutting out a part of the second group tube 22 on the first group tube 25 side.
A second extending portion 47c extending from the outer periphery of the tubular portion 46 to the outer peripheral side is provided on the outer peripheral side of the first extending portion 47a, and the third group cam follower 41 is provided at the tip of the second extending portion 47c. It is provided.
The extending portion 47a of the third group barrel 23 is within the range of the length of the third group inserting portion 34 formed in the second to fourth group barrel 24 in the optical axis OA direction, and the optical axis OA with respect to the second to fourth group barrel 24. It can move in any direction. The length of the tubular portion 46 in the optical axis OA direction is longer than the length of the third group insertion portion 34 in the optical axis OA direction.

Further, on the outer periphery of the tubular portion 46 of the third group barrel 23, third group outer circumferential convex grooves 42 extending in the optical axis OA direction are formed at three substantially equal circumferential positions. A slightly recessed third group outer peripheral groove 43 extends on both sides of each third group outer peripheral groove 42.
On the inner periphery of the tubular portion 46 of the third group barrel 23, third group inner circumferential grooves 44 extending in the optical axis OA direction are formed at three substantially equal circumferential positions. On both sides of the third group inner peripheral concave groove 44, a third group inner peripheral convex groove 45 slightly protruding to the inner diameter side extends.
The 2-4 group convex groove 32 is key-fitted to the 3rd group inner peripheral concave groove 44, and the 2-4 group convex groove 32 is key-fitted to the 3rd group inner peripheral convex groove 45. The third group tube 23 and the third group tube 23 are slidable in the optical axis OA direction.

FIG. 5 is a perspective view of the first group cylinder 21. First group cam followers 51 are formed at three substantially equal circumferential positions on the outer circumference of the camera body side end of the first group cylinder 21.
On the inner circumference of the first group barrel 21, first group concave grooves 52 extending in the optical axis OA direction are formed at three substantially equal circumferential positions. On both sides of the first-group concave groove 52, a first-group convex groove 53 slightly protruding to the inner diameter side extends.
The third group outer peripheral convex groove 42 is key-fitted to the first group inner peripheral concave groove 53, the third group outer peripheral convex groove 43 is key fitted to the first group inner peripheral concave groove 52, and the first group cylinder 21 and the third group cylinder 23 are slidable relative to each other in the optical axis OA direction.

FIG. 6 is a development view of the fixed barrel 12 and the zoom operation ring 11. As shown in the figure, the first-third group straight-moving groove 61 and the second-fourth group straight-moving groove 62 are formed in the fixed cylinder 12 at three substantially equal positions in the circumferential direction.
On the inner surface of the zoom operation ring 11, a second-fourth group cam 72, a third-group cam 71, and a first-group cam 73 indicated by dotted lines are formed at three substantially equal positions in the circumferential direction.

The first-group cam follower 51 is fitted into the first-group cam 73 of the zoom operation ring 11 and the first-third group straight-moving groove 61 of the fixed barrel 12.
When the zoom operation ring 11 rotates, the first-group cam follower 51 moves straight along the first-third group straight-moving groove 61 and moves along the first-group cam 73 in the optical axis OA direction.

The second-fourth group cam follower 31 is fitted into the second-fourth group cam 72 of the zoom operation ring 11 and the second-fourth group rectilinear groove 62 of the fixed barrel 12.
When the zoom operation ring 11 rotates, the second-fourth group cam follower 41 moves straight along the second-fourth group linearly moving groove 62 and moves in the optical axis OA direction along the second-fourth group cam 72.
At this time, the 2-4 group convex groove 32 and the 2-4 group convex groove 32 of the 2-4 group cylinder 24 are arranged along the third group inner peripheral concave groove 44 and the third group inner peripheral convex groove 45 in the optical axis OA direction. It slides relatively.

The third group cam follower 41 is fitted into the third group cam 71 of the zoom operation ring 11 and the first to third group straight-moving grooves 61 of the fixed barrel 12.
When the zoom operation ring 11 rotates, the third group cam follower 41 moves in the optical axis OA direction along the third group cam 71 while moving straight along the first to third group rectilinear grooves 61.
At this time, the third group outer peripheral convex groove 42 and the third group outer peripheral convex groove 42 of the third group tube 23 slide relative to each other along the first group concave groove 52 and the first group convex groove 53 in the optical axis OA direction.
Further, as described above, the third group inner peripheral concave groove 44 and the third group inner peripheral convex groove 45 are arranged along the optical axis OA along the 2-4 group convex groove 32 and the 2-4 group convex groove 32 of the 2-4 group cylinder. Slide relative to the direction.

(Comparison form)
7A and 7B are schematic cross-sectional views of a main part of a lens barrel 1A of a comparative example of the present embodiment, which corresponds to FIG. 1, in which (a) shows a wide state and (b) shows a tele state.
The lens barrel 1A of the comparative example is different from the embodiment in that the third group holding member 23A for holding the third lens group L3 does not have the tubular portion 46 as shown in FIGS. 1 and 4 of the embodiment. It is a point. In FIG. 7, the same parts as those in the embodiment are designated by the same reference numerals as those in the embodiment, and the description thereof will be omitted.

In the comparative form, the first group cylinder 21 and the second group cylinder 24 are fitted to each other in the optical axis OA direction. The third group holding member 23A is fitted to the 2-4 group tube 24 on the inner peripheral side in the optical axis OA direction, but is fitted in the space between the second lens group L2 and the fourth lens group L4. Since they are matched, the fitting length is shorter than the fitting of the tubular portion 46 with the third group cylinder 23 in the embodiment.
The third group holding member 23A has a manufacturing clearance with the third group cam follower 41. According to the comparative embodiment, the length of fitting of the third group holding member 23A with the second-fourth group tube 24 is short, so that the third lens group L3 is more likely to be decentered due to this clearance as compared with the embodiment.
Also in terms of optical characteristics, in an optical system in which the second lens unit L2 and the fourth lens unit L4 move in conjunction with each other, the eccentricity of the third lens unit L3 greatly affects the optical performance, and the eccentricity accuracy is severe. In the comparative form, it is difficult to make the eccentricity accuracy high.

(Effects of the embodiment)
However, according to the present embodiment, the third group cylinder 23 has the tubular portion 46. The tubular portion 46 is fitted to the first group barrel 21 and the second to fourth group barrel 24 in the optical axis OA direction (long fitting length).
That is, since the tubular portion 46 of the third group tube 23 is fitted to both the first group tube 21 and the 2-4 group tube 24, the eccentric angle of the third lens group L3 due to the manufacturing clearance may vary. The size of the lens barrel 1 can be reduced, and the yield of the lens barrel 1 can be improved.

Also, the 2-4 group convex groove 32 is key-fitted to the 3rd group inner peripheral concave groove 44, and the 2-4 group convex groove 32 is key-fitted to the 3rd group inner peripheral convex groove 45. The barrel 24 and the third group barrel 23 are slidable relative to each other in the optical axis OA direction.
Then, the third group outer peripheral convex groove 42 is key-fitted to the first group inner peripheral concave groove 53, and the third group outer peripheral convex groove 43 is key fitted to the first group inner peripheral concave groove 52. The group tube 23 and the group tube 23 are slidable in the optical axis OA direction.
Therefore, the movement between the first group barrel 21 and the third group barrel 23, the third group barrel 23 and the 2-4 group barrel 24 becomes smooth, and the wobbling in the circumferential direction relative to each other is further avoided.

Furthermore, since the length of the tubular portion 46 is longer than that of the third group insertion portion 34, eccentricity can be further suppressed.

Although the embodiment has been described above, the embodiment can be variously modified and changed.
For example, in the present embodiment, the first group cylinder 21, the third group cylinder 23, and the third group cylinder 23 and the 2-4 group cylinder 24 are key-fitted. However, the present invention is not limited to this. Alternatively, it may be a diameter fitting which is fitting by contact of the peripheral surface.

L1: first lens group, L2: second lens group, L3: third lens group, L4: fourth lens group, OA: optical axis, 1: lens barrel, 2: camera body, 11: zoom operation ring, 12: fixed cylinder, 13: lens side mount, 21:1 group cylinder, 22:2 group cylinder, 23:3 group cylinder, 24:2-4 group cylinder, 25:4 group lens frame, 31:2-4 group Cam follower, 32:2-4 group convex groove, 33:2-4 group concave groove, 34:3 group inserting portion, 41:3 group cam follower, 42:3 group outer peripheral convex groove, 43:3 group outer peripheral concave groove, 44 : 3 group inner peripheral concave groove, 45: 3 group inner peripheral convex groove, 46: cylindrical portion, 47: lens holding portion, 51: 1 group cam follower, 52: 1 group concave groove, 53: 1 group convex groove, 61 : Group straight advance groove, 62: Group straight advance groove, 71:3 group cam, 72:2-4 group cam, 73:1 group cam

Claims (7)

A tubular first holding portion for holding the first lens;
A second holding part that holds the second lens and is connected to the first holding part;
A third cylindrical holding unit that holds a third lens arranged between the first lens and the second lens, and extends on the outer peripheral side of the first holding unit in the optical axis direction. ,
The first holding part has an insertion part through which the third holding part penetrates to the outer peripheral side of the first holding part, between the second holding part and the second holding part.
The first holding unit is movable in the optical axis direction along the third holding unit,
One of a concave groove or a convex groove is formed on the outer periphery of the first holding portion,
The other of the concave groove or the convex groove is formed on the inner circumference of the third holding portion,
The concave groove and the convex groove are fitted to each other,
Lens barrel. A tubular first holding portion for holding the first lens;
A second holding part that holds the second lens and is connected to the first holding part;
A cylindrical third holding portion that holds a third lens arranged between the first lens and the second lens, and extends on the outer peripheral side of the first holding portion in the optical axis direction; Prepare,
The first holding part has an insertion part through which the third holding part penetrates to the outer peripheral side of the first holding part, between the second holding part and the second holding part.
The first holding unit is movable in the optical axis direction along the third holding unit,
A first cam follower is provided on the outer periphery of the second holding portion,
A third cam follower is provided on the outer periphery of the third holding portion,
An operation ring provided with a first cam groove into which the first cam follower fits and a third cam groove into which the third cam follower fits is provided on the outer peripheral side of the first holding portion.
Lens barrel. The lens barrel according to claim 1 or 2, wherein
On the outer peripheral side of the third holding portion, a cylindrical fourth holding portion for holding the fourth lens is provided,
The fourth holding unit is movable in the optical axis direction along the third holding unit,
Lens barrel. It is a lens barrel as described in any one of Claims 1-3, Comprising:
The third holding unit has a length in the optical axis direction longer than that of the insertion unit,
Lens barrel. A tubular first holding member that holds the first lens and the second lens and that has a first engaging portion on the outer peripheral side;
A second cylindrical holder that holds a third lens arranged between the first lens and the second lens, and has a second engaging portion that engages with the first engaging portion on the inner peripheral side. And a member,
The first holding member is movable in the optical axis direction with respect to the second holding member,
Lens barrel. A tubular first member holding the first lens and the second lens and having a first follower;
A cylindrical second member that holds a third lens arranged between the first lens and the second lens, has a second follower, and extends on the outer peripheral side of the first member in the optical axis direction; ,
An operating ring that has a first cam groove that engages with the first follower and a second cam groove that engages with the second follower, and is arranged on the outer peripheral side of the first member and the second member. and, with a,
Said first member, Ru movable der the second optical axis direction along the member,
Lens barrel. An optical device comprising the lens barrel according to claim 1.

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