JP2003195140A - Lens adapter device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lens adapter device capable of exchanging lens by easily mounting or demounting an external lens with respect to a camera main body. <P>SOLUTION: An engagement pin 74 capable of rocking and a protection pin 78 for preventing the excessive deformation of the pin 74 are provided in a 2nd adapter barrel 71 in which a conversion lens 60 and a protection barrel 81 are mounted. In the case of mounting the adapter barrel 71 on a 1st adapter barrel 51, the pin 74 of the adapter barrel 71 is engaged and locked in the groove part for guiding 54 and a groove part to be engaged 55 of the adapter barrel 51 fixed in the camera main body 30, thereby, the adapter barrel 71 is mounted through one action. Simultaneously, in a locked state, the pin 78 of the adapter barrel 71 is engaged in a 2nd groove part for guiding 56 provided in parallel with the groove part 55 of the adapter barrel 51, whereby the pin 78 and the groove part 56 function as a stopper even when the adapter barrel 71 is pulled in a demounting direction by strong force. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens adapter device for a camera, and more particularly to a lens adapter device for attaching an external lens such as a teleconversion lens to a lens portion of a camera body.

[0002]

2. Description of the Related Art It is desirable for a camera to be able to select a wide range of its focal length. Even a compact type camera may be required to shoot at a focal length outside the range of the built-in lens.

Therefore, an external lens such as a so-called wide conversion lens or a tele-conversion lens is prepared in front of the built-in lens for changing the magnification.

It is desirable to use a general-purpose external lens, because if the external lens is made for each camera, the lens becomes expensive.

However, it is often difficult to directly attach these external lenses due to the size limitation of the compact camera.

Therefore, in order to attach these external lenses, as described in Japanese Patent Laid-Open No. 2000-235222 by the present applicant, an adapter designed for each camera is attached to the taking lens unit or the lens barrel, and the adapter is attached. An external lens has been proposed so that it can be attached.

[0007]

By the way, in the conventional lens adapter type, an external lens is connected to one end of the adapter by screw connection, and the other end of the adapter is connected to the lens part of the camera body by screw connection. Mounting.

Since they are connected by screw joining, the external lens cannot be inserted or removed with one touch. This is not an easy task, especially in cold regions where you wear gloves especially when shooting outdoors.

If it takes a long time to remove the lens, there is a possibility that the photo opportunity may be missed or the screw portion may be destroyed by applying force.

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a lens adapter device in which an external lens can be easily attached to or detached from the camera body to replace the lens. Is.

[0011]

According to a first aspect of the present invention, there is provided a lens adapter device for connecting an external lens and a photographing lens of a camera body, wherein the lens adapter device has one end attached to the camera body. A first adapter barrel and the external lens are attached to one end of the first adapter barrel, and the other end of the first adapter barrel is fitted to the other end of the first adapter barrel to be assembled to be combined. An adapter cylinder, an engagement piece provided on the peripheral surface of any one of the first adapter cylinder or the second adapter cylinder so as to be elastically displaceable, and the same with the engagement piece provided A protection piece for protecting the engagement piece, which is provided on a peripheral surface of the adapter cylinder and closer to a connection end with another adapter cylinder than the engagement piece, and the engagement piece are provided. Extends to the peripheral surface of the adapter tube that is not And a guide portion for guiding the engagement piece and the protection piece, and the guide portion is provided on the peripheral surface of the adapter cylinder on the side where the engagement piece is not provided. An engaged portion to which the piece is urged and engaged,
Is provided.

According to the present invention, the second adapter cylinder having the external lens such as the tele-conversion lens attached thereto is provided with the engagement piece (engagement pin) which is oscillatably planted, and is fixed to the second adapter cylinder. When the second adapter tube is attached to the first adapter tube, the engaging piece and the protective piece of the second adapter tube are fixed to the camera body. The second adapter tube can be attached to the first adapter tube with one touch by engaging the guide portion and the engaged portion provided on the adapter tube. Moreover, even when a large force is applied in the direction in which the second adapter barrel is pulled out from the camera body side with the second adapter barrel mounted on the first adapter barrel, the second adapter barrel is fixed to the second adapter barrel. Since the protective piece can prevent the movement of the second adapter cylinder by abutting the inner wall of the guide portion of the first adapter cylinder, for example, the lock installed in the second adapter cylinder swingably. The engagement piece can be protected without giving a displacement that would damage the joint piece.

A second aspect of the present invention is a lens adapter device for connecting an external lens and a photographing lens of a camera body, wherein the lens adapter device has one end attached to the camera body. Adapter barrel, and a second adapter barrel in which the external lens is attached to one end portion, and the other end portion is fitted into the unattached end portion of the first adapter barrel to be combined. An engagement piece provided on the peripheral surface of one of the first adapter cylinder and the second adapter cylinder so as to be elastically displaceable, and the engagement piece so as not to expose the engagement piece. A protective cylinder that covers the adapter cylinder that is provided with, a guide portion that extends on the peripheral surface of the adapter cylinder that is not provided with the engaging piece, and that guides the engaging piece; If you do not have a piece The peripheral surface of the descriptor tube, provided connected to the guide portion, wherein the engaging piece is provided with the engaged portion to be engaged is biased, the.

According to the present invention, the second adapter cylinder having the external lens such as the tele-conversion lens attached thereto is provided with the engagement piece (engagement pin) which is oscillatably planted, while the outer circumference of the second adapter cylinder is provided. In addition, a protective cylinder for covering the second adapter cylinder is provided. When the second adapter cylinder is attached to the first adapter cylinder, the engagement piece of the second adapter cylinder is such that the guide portion and the engaged portion provided on the first adapter cylinder fixed to the camera body. By engaging the second
The adapter tube can be attached to the first adapter tube with one touch, and the protective tube that covers the second adapter tube prevents the engagement piece (engaging pin) of the second adapter tube from being prepared. It is possible to protect the engagement piece by preventing the external force from being applied and damaging it.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing the outer appearance of a lens adapter device according to an embodiment of the present invention, and FIG. 2 is a vertical cross-sectional view showing the main parts of the lens adapter device.

The lens adapter device 10 is an electronic camera 2
The first adapter 50 attached to 0, the second adapter 70 attached to the teleconversion lens 60 as an external lens, and the second adapter 70 attached to the first adapter 50 so as to cover the outer periphery of the second adapter 70. And a protection adapter 80 attached to the.

The electronic camera 20 includes a camera body 30 and a lens section 40 provided on the front side of the camera body 30.
And are equipped with.

The electronic camera 20 includes a camera body 30 and a lens section 40 provided on the front side of the camera body 30.
And are equipped with.

The camera body 30 has a housing 31, and the housing 31 has a control panel 3
2, a zoom lever 33, a flash 34, a viewfinder window 35, a remote control reception window 36, a release switch 37, a power switch 38, and a viewfinder eyepiece 39.

The lens portion 40 is formed in a cylindrical shape and stores a zoom lens unit 42, which will be described later, and a zoom lens unit 42 as a photographing lens provided coaxially with the lens storage portion 41. Equipped with.

FIG. 2A shows the lens portion 4 of the camera body 30.
After assembling the first adapter 50 with respect to 0, a vertical sectional view showing a state in which the second adapter 70 in which the tele-conversion lens 60 and the protection adapter 80 are previously attached is attached to the first adapter 50. Shows. Figure 2
FIG. 2B shows a state in which the one-touch mounting type second adapter 70 is removed from the state of FIG. It shows a state in which the lens lid 43 is attached to the tip portion 53 of the first adapter 50. 2C shows that the lens adapter 43 is attached to the tip end portion 41 of the lens housing portion 40 of the camera body 30 after the first adapter 50 is further removed from the camera body from the state of FIG. 2B.
It shows a state where is attached.

As shown in FIGS. 2B and 2C, the lens lid 43
Can be attached to the tip 41a of the lens housing 41 or the tip 53 of the first adapter 50 in order to protect the zoom lens unit 42 when the camera is not used.

The zoom lens unit 42 is of a collapsible type so that the tip end side thereof is completely hidden by the lens housing portion 41 when being housed. Reference numeral 42a denotes the tip end surface of the zoom lens unit 42 (see FIG. 2 (a)).

A screw groove 41b is formed on the inner wall of the tip portion 41a of the lens housing portion 41. Further, the lens lid 43 is provided with a protrusion 43a and an engaging portion 43b that can be engaged with the screw groove 41b or a screw groove 53a described later.

The first adapter 50 has a first adapter cylinder 51 formed in a cylindrical shape. The first adapter cylinder 51 is made of metal such as aluminum and titanium. The inner diameter of the adapter cylinder 51 is formed larger than the maximum diameter of the zoom lens unit 42 described above. Also, the first
A thread groove 52a that is screwed into the above-described thread groove 41b is formed on the outer periphery of the base end portion 52 of the adapter barrel 51 on the camera body side, and the tip end portion 53 on the tele conversion lens 60 side.
A thread groove 53a that can be screwed into a thread groove 62a of the tele-conversion lens 60 described later is formed on the inner periphery of the.

On the outer periphery of the first adapter 50, a groove portion 54 is formed which extends from the end face in the optical axis direction of the peripheral face and serves as a first guide portion for guiding the engagement pin 74 and the protection pin 78. There is. The groove portion 54 is formed such that the groove width in the vicinity of the end face entrance into which the engagement pin 74 described later is inserted is wider than the groove path on the way. This facilitates the engagement of the engagement pin 74. Then, the engaging pin 74 is connected to the groove 54 at a position before the end of the groove 54 by a predetermined dimension.
A groove portion 55 that functions as an engaged portion of is formed in a direction around the optical axis. Further, a groove portion 56, which is connected to the terminal end portion of the groove portion 54 and serves as a second guide portion for further guiding the protection pin 78 that has passed through the groove portion 54, is formed in the direction around the optical axis.

An engaging pin 74, which will be described later, is engaged with the groove portion 54 and the groove portion 55 to move, and is finally locked (locked) at the end portion of the groove portion 55. A protection pin 78, which will be described later, is engaged with the groove 54 and the groove 56 to move, and when the engaging pin 74 is finally locked (locked),
The protection pin 78 is located at the end portion of the groove portion 56 which is the second guide portion.

The second adapter 70 has a second adapter cylinder 71 formed in a cylindrical shape. The second adapter cylinder 71 is made of a metal such as aluminum or titanium like the first adapter cylinder 51. The inner diameter of the portion of the second adapter cylinder 71 excluding the end portion 73 side is equal to the first adapter cylinder 5
1 is substantially equal to the outer diameter of the first adapter cylinder 71, the inner surface of the second adapter cylinder 71 circumscribes the outer surface of the first adapter cylinder 51, and the second adapter cylinder 71 is slidable with respect to the first adapter cylinder 51. ing. The thread groove 6 of the tele-conversion lens 60, which will be described later, is formed on the inner circumference of the tip portion 73 of the second adapter cylinder 71.
A screw groove 73a that can be screwed into 2a is formed.

The tip portion 73 of the second adapter cylinder 71
A protective cylinder 8 to be described later is provided on the outer peripheral portion (excluding the collar portion).
A screw groove 73b that can be screwed into a screw groove 82a cut on the inner circumference of the tip end portion 82 of No. 1 is formed.

Further, on the outer periphery of the second adapter 70,
Two long holes 75a, 75
b is formed, and the specific portion (hereinafter, referred to as a rib) 72 sandwiched between the long holes 75a and 75b is easily elastically deformed in the front-back direction (that is, parallel to the optical axis) (that is, has a spring property). 2) It is formed like a bridge. An engaging pin 74 as an engaging piece is erected almost at the center of the rib 72 so as to project to the inner surface side of the second adapter 70. The engagement pin 74 is made of metal such as stainless steel. According to such a configuration, the engaging pin 74 can be formed integrally with the adapter cylinder without using another spring material or the like, so that there is an advantage that it can save space and be economical.

The protection adapter 80 includes a protection cylinder 81 formed in a cylindrical shape. The protective cylinder 81 is made of a metal such as aluminum or titanium like the first and second adapter cylinders 51 and 71. A screw groove 82a is formed on the inner circumference of the tip end portion 82 of the protection cylinder 81.

Furthermore, a position on the outer periphery of the second adapter 70 on the base end side and on a straight line parallel to the same optical axis as the engaging pin 74 (position closer to the end than the engaging pin 74).
In addition, the protection pin 78 as a protection piece has the second adapter 70.
It is planted so that it protrudes to the inner surface side of. While the engaging pin 74 can swing in the direction parallel to the optical axis,
The protection pin 78 is fixed to the second adapter 70 and has a function (described later) for preventing the engagement pin 74 from being excessively deformed.

The teleconversion lens 60 includes a cylindrical tubular body 61 and a cylindrical mounting portion 62 formed coaxially and integrally with the tubular body 61 (with an outer diameter slightly smaller than the tubular body 61). I have it. The lens 6 is provided on the inner circumference of the cylindrical body 61.
3 to 65 are held. A screw groove 62a is formed on the outer periphery of the mounting portion 62.

In the configuration of FIG. 1, when the tele-conversion lens 60, which is an external lens, is attached to the first adapter barrel 50 fixed to the camera body 30, the second adapter barrel 70 to which the tele-conversion lens 60 is previously attached is attached. By preparing the second adapter cylinder 70 and moving the second adapter cylinder 70 into the first adapter cylinder 50 in a direction parallel to the optical axis and fitting them together, the second adapter cylinder 70 can be attached (or removed) with one touch. This mounting or removal is performed by the first adapter cylinder 5
1. The guide groove portions 54, 56 and the engaged groove portion 5 provided on
5 and the swingable engagement pin 74 protrudingly provided on the inner surface side of the second adapter cylinder 70 and the protection pin (fixing pin) 78 protrudingly provided on the inner surface side of the second adapter cylinder 70. It has a structure that can be easily mounted and mounted.

FIG. 3A is a sectional view taken along the line BB in FIG. 4, showing the lens section 40 and the first adapter 5 in FIG. 2A.
0, the second adapter 70, the protection adapter 80, and the teleconversion lens 60 are joined, and the rib 72, the engagement pin 74, the protection pin 78, and the guide groove 54 at that time are enlarged. FIG. 3B shows the rib 72, the engagement pin 74, and the protection pin 78 in FIG. 3A in a further enlarged manner.

In FIG. 3 (a), the inner diameter of the screw 41b portion on the inner circumference of the tip portion 41a of the lens housing portion 41 and the inner diameter of the screw 53a portion of the tip portion 53 of the first adapter 50 have the same diameter. Therefore, the same lens lid 43 can be mounted as shown in FIGS. 2 (b) and 2 (c). Second
The adapter 70 and the protection adapter 80 of the second adapter 70 are the thread groove 73 b on the outer periphery on the tip side of the second adapter 70 and the protection adapter 80.
Are joined to each other by a thread groove 82a on the inner circumference of the tip side.

In FIG. 3B, the second adapter cylinder 71
Surface (lower surface in the drawing) of the engaging portion (large diameter portion) of the engaging pin 74 that is crimped to the rib 72 of FIG.
Between the bottom surface (the upper surface in the drawing) of the second adapter 70 and the first adapter 50 along the groove 54 (and 55) so as not to rub the upper surface and the lower surface in the drawing. A gap A is formed. In addition, the rib 72 of the second adapter 70 is front and rear (parallel to the optical axis).
In a predetermined range where the outer peripheral surface of the rib 72 and the inner surface of the protection adapter 80 are slidably contacted with each other so as to be elastically displaceable in the direction (that is, can be moved back and forth), a concave portion 83 is formed so that a gap is formed on the inner surface of the protective cylinder 81. Has been formed.

The lens adapter device 10 thus constructed is used as follows. That is, at the time of normal shooting, by turning on the power switch 38, the zoom lens unit 42 housed inside the lens housing portion 41 projects from the lens housing portion 41. In addition, the photographer appropriately operates the zoom lever 33 to expand and contract the zoom lens unit 42 as shown in FIG. In FIG. 2A, W indicates the position of the tip at the time of wide-angle shooting and S at the time of storage.

On the other hand, when enlarging the magnification by the zoom lens unit 42 and performing high-magnification photography, the teleconversion lens 60 is mounted as follows.

Then, the base end portion 52 of the first adapter 50.
Is screwed into the lens storage portion 41 and fixed.

Next, the tip portion 7 of the second adapter 70 is previously prepared.
3 to the screw groove 73b on the outer surface of the protective adapter 80
2a is screwed in and attached, and the second adapter 70 is previously attached.
The screw groove 62a of the mounting portion 62 of the tele-conversion lens 60 is screwed into the screw groove 73a on the inner surface of the tip portion 73 of
Wear it.

Then, the base end side (camera body side) of the adapter cylinder 71 of the second adapter 70 having the protective adapter 80 and the teleconversion lens 60 mounted thereon is circumscribed on the outer peripheral surface of the first adapter 50. By sliding and rotating and locking the second adapter 70, the second adapter 70 is mounted in a state of covering almost the entire outer peripheral surface of the first adapter 50. At this time, the engagement pin 74 pivotally planted on the inner peripheral side of the second adapter 70 passes through the guide groove 54 of the first adapter 50, and is provided in the direction around the optical axis for engagement. At the same time as being engaged with the groove 55 and being locked (locked) at the final end of the groove 55, the second adapter 70 is erected on the tip side of the engaging pin 74 (fixing pin). The protective pin 78 passes through the guide groove portion 54 of the first adapter 50 and is then engaged with the guide groove portion 56 provided in the optical axis rotation direction.

The photographer appropriately operates the zoom lever 33 to expand / contract the zoom lens unit 42 as shown in FIG. 2 (a). At this time, the zoom lens unit 42
Since the outer diameter of is smaller than the inner diameter of the first adapter cylinder 51,
It does not interfere by contacting the adapter cylinder 51. Therefore, the photographer can smoothly perform the zoom operation.

The load of the first adapter 50, the second adapter 70, the protection adapter 80 and the tele-conversion lens 60 is applied to the camera body 3 via the lens housing section 41.
It takes 0 and does not affect the zoom lens unit 42. Therefore, the drive system of the zoom lens unit 42 is not burdened, and there is no fear of causing a failure.

As described above, in the lens adapter device 10 according to the present embodiment, the teleconversion lens 60 is fixed to the camera body 30 side by the one-touch method using the second adapter 70. Therefore, the teleconversion lens 60 can be mounted easily and quickly. Moreover, the engagement pin 74 of the second adapter 70 is the first
Of the second adapter 7 in the process of moving in the engaged groove portion 55 of the adapter 50 or in the state of being locked in the groove portion 55.
Even if a large force is applied to the side opposite to the camera body side with respect to 0, the protection pin 7 of the second adapter 70
8 contacts the wall 55a (close to the engaged groove 55) of the guide groove 56 (see FIG. 4 (a)) to act as a stopper, so that the elastically displaceable engagement of the second adapter 70 is achieved. It is possible to prevent the pin 74 from being inadvertently applied with a large force and damaged.

On the other hand, when the tele-conversion lens 60 is not used, the second adapter 70 with the tele-conversion lens 60 attached is removed and the first adapter 50 is left attached to the lens section 40 of the camera body 30. Normal shooting can be performed even in the state. In this manner, when only the first adapter 50 is connected to the camera body 30, the appearance of the adapter 50 is outside the shooting range of the shooting lens (not within the shooting field of view). With this configuration, the first adapter 5
Even with 0 attached, you can shoot normally without an external lens. In other words, it is not necessary to remove the first adapter 50 for performing normal shooting.

When the tele-conversion lens 60 is not used, the second adapter 70 having the tele-conversion lens 60 and the protective adapter 80 and the first
The adapter 50 can be removed together or separately from the lens unit 40, and normal shooting can be performed only by the electronic camera 20, and the portability as a camera can be improved.

Next, the operation when the second adapter 70 with the tele-conversion lens 60 and the protection adapter 80 attached thereto is attached to and detached from the first adapter 50 will be described.

FIG. 4 is a partial plan view of the first adapter 50, the protection adapter 80, and the second adapter 70 in a disassembled state (before joining). FIG. 4A shows the first adapter 50, b) is the protection adapter 80, (c) is the second adapter 7
It is each top view of 0.

In FIG. 4, the protection adapter 80 of (b) has a function of covering and protecting the outer periphery of the second adapter 70 having the engaging pin 74, and the second adapter 70 of (c). The operation for mounting and disengaging the engagement pin 74 and the protection pin 78 in (1) with respect to the guide portions 54, 56 and the engaged portion 55 in the first adapter 50 (a) is shown. The outer shape of the tip portion 12 of the protection adapter 80 of FIG. 4 (b) is different from that of FIG. 1, but is functionally the same as that of FIGS.

When the second adapter cylinder 71 is fitted to the first adapter cylinder 51, first, the protection pin 78 and the engagement pin 74 protruding on the inner surface of the second adapter cylinder 71 are attached to the first adapter cylinder 71. The groove 54a formed wide from the vicinity of the end surface of the cylinder 51 to the peripheral surface enters the guide groove 54 (this is wide so that the pins 78 and 74 can be easily inserted even if the insertion positions are a little different). It slides in the direction of the optical axis through the passage portion 54b having a constant width. The protection pin 78 and the engaging pin 74 are respectively denoted by reference numeral 78.
When it comes to the positions indicated by a1 and 74a1, the contact surface 73 on the inner peripheral side of the thickened tip portion 73 of the second adapter cylinder 71
c (see FIG. 3 (a)) abuts on the distal end surface 53b of the distal end portion 53 of the first adapter cylinder 51, and the protection pin 78 and the engaging pin 74 are located above the positions indicated by reference numerals 78a1 and 74a1 in the camera. It cannot be slid to the main body.

At this position 78a1, the outer peripheral surface of the protection pin 78 is connected to the guide groove 54 which is the first guide portion, and the guide groove portion which is the second guide portion is provided in the direction around the optical axis. It is located almost at the center of the groove 56, and is provided with a slight margin with respect to the groove width between the inner walls on both sides of the groove 56 (that is, the pin 78 in consideration of the processing error in the groove width of the groove 56). A little larger than the outer diameter).

At the position 74a1, the engaging pin 7
Part of the outer peripheral surface of No. 4 is an inner wall 55 of an engaged groove portion 55 that is connected to the guide groove portion 54 and is provided in the direction around the optical axis.
It is located at a position slightly before the position of a (a position below the position of the inner wall 55a in the figure).

Therefore, when the protection pin 78 and the engagement pin 74 reach the positions 78a1 and 74a1, respectively, when the second adapter 70 is rotated in the direction of the arrow (see FIG. 4 (a)),
Although the protection pin 78 moves in the right direction in the drawing in the groove 56 without contacting the inner wall, and finally reaches a position a little before the final end of the groove 56 (inner right wall in the drawing), indicated by reference numeral 78a2, The outer peripheral surface of the engagement pin 74 is biased toward the camera body side by the inner wall 55a (that is, the rib 72 to which the pin 74 is attached is shown by reference numeral 72 'in FIG. 4 (c). (While moving to the position indicated by reference numeral 74 ') while being elastically deformed on the camera body side], it moves in the direction of the arrow, and finally a part of the outer peripheral surface of the engagement pin 74 is engaged with the recessed portion. It is fitted in 55b and positioned (locked) at the position indicated by reference numeral 74a2. In this locked state, the pin 74 is positioned (fixed) by contacting two points of contact points 55c and 55d on the inner wall of the groove 55. In this positioning state, the engagement pin 74 has a weaker biasing force received from the wall surface than when the pin 74 is in contact with the inner wall 55a during movement.

On the contrary, the engagement pin 74 has the locking position 74a.
In order to rotate the second adapter 70 in the direction opposite to the arrow in the drawing from the state of 2, it is possible to apply a force sufficient to overcome the biasing force of the rib 72 at the pin position 74a2. A click state (click feeling) is obtained by engagement and disengagement of the pin 74 with respect to the engagement recess 55b.

Position 74a2 and position 74a1 of the engaging pin 74
Between the contact points 55c and 55d in the groove 55 (the rib 72).
No.) With a small biasing force, it is locked in a state of being slightly biased downward in the drawing. Therefore, the engagement recess 55
When releasing the locked state of the pin 74 with respect to b, the wall 5
The lock can be unlocked with a force that opposes the biasing force that is less than the biasing force on 5a. That is, the photographer moves the second adapter cylinder 71 in the direction opposite to the arrow direction (with a little force).
By simply turning the pin 74, the locked state is released, and the pin 74 can be returned from the position 74a2 to the position 74a1.

On the other hand, the protection pin 78 has a second position when the engagement pin 74 is moving in the groove 55 which is the engaged portion or when the engagement pin 74 is locked in the engagement recess 55b. When the adapter cylinder 71 is forcibly pulled in a direction opposite to the camera body side (downward direction in the drawing) with a large force, the engaging pin 74 that is planted on the elastically deformable rib 72 may be damaged. However, when pulled by such a force, the protection pin 78 comes into contact with the inner wall 56a of the guide groove portion 56 (close to the engaged groove portion 55) and thus serves as a stopper for the engagement pin 74. The amount of displacement of the engagement pin 74 can be suppressed to a predetermined value or less, and damage to the engagement pin 74 and the rib 72 can be prevented. Therefore, in the normal engagement state,
When the protection pin 78 is located in the groove 56, the gap formed between the outer peripheral surface of the pin 78 and the inner wall 56a of the groove 56 is
It must be set within a range of spring stress (of the rib 72) that does not lead to damage of the engaging pin 74 when the engaging pin 74 is displaced.

By the way, the guide groove portion 54 of the first adapter 50 and the engagement portion (large diameter portion) of the engagement pin 74 of the second adapter 70 are engaged with each other to make the first and second adapters. To attach the cylinders 51 and 71 to each other, an instruction mark as a position alignment display is required. Moreover, the instruction mark is
It is desirable that there are a plurality of sets on the outer peripheral surfaces of the first and second adapter cylinders 51 and 71.

The reason why this alignment display is required is as follows. That is, when the first adapter 50 and the lens portion 40 of the camera body 30 are connected, the first adapter 50 is screwed into the lens portion 40 and screwed, but the tip portion 41a of the lens portion 40 is connected. When forming the female screw on the inner circumference and the male screw on the outer circumference of the base end portion 52 of the first adapter 50 by processing, it is not generally decided from which position the screw is cut. Therefore, when the first adapter 50 is screwed and attached to the lens portion 40 of the camera body 30, the position of the guide groove portion 54 provided on the outer peripheral surface of the first adapter 50 is not always easy for the photographer to see. The guide groove 54 may not necessarily come to the position, but may come to a lower position (back surface side position) on the outer peripheral surface, which is rather difficult for the photographer to see. Therefore, a mark (instruction mark) is required on the outer peripheral surface of each adapter cylinder as an alignment display between the first and second adapter cylinders. Furthermore, if there is only one mark (instruction mark) on the outer peripheral surface of each adapter cylinder, the instruction mark on the outer peripheral surface of the first adapter cylinder is difficult to see for the photographer due to screw processing. Position, and it is necessary to provide a plurality of marks (instruction marks) on the outer peripheral surface of the adapter cylinder.

FIG. 5 shows an embodiment of an instruction mark used as an alignment display for mounting the first and second adapters. However, the protective cylinder 81
Is omitted. 5A is a perspective view showing a state before fitting and mounting, and FIG. 5B shows a state in which the second adapter 70 is fitted along the guide groove portion 54 of the first adapter.
FIG. 5C shows a state in which the second adapter 70 is rotated and mounted (locked) from the state of FIG. 5B.

As shown in FIG. 5 (a), when the first adapter cylinder 51 and the second adapter cylinder 71 are fitted, the engaging pin 74
For adjusting the entrance position of the guide groove 54 and the guide groove 54
The indications 76a, 76b, 76c of the second adapter cylinder 7
Three different mark shapes (Δ, ◯, □) are formed at approximately 120 ° intervals on the outer peripheral surface of the base end portion 77 of No. 1.

Then, in order to correspond to this first display, the outer peripheral surface of the tip end portion 53 of the first adapter cylinder 51 is substantially 1
Three mark shapes (Δ, ◯, □) similar to the above-mentioned instruction mark are formed at three positions (indicated by reference numerals 57a, 57b, 57c) at 20 ° intervals.

The instruction marks 76a, 76b, 76c on the second adapter cylinder 71 and the first adapter cylinder 5
The instruction marks 57a, 57b, and 57c in 1 can be used as marks if the end portion of either one of the adapter cylinders has a shape characteristic. Therefore, the indication marks 76a, 76b, 76c (or 57a, 57) are positively applied to only one of the second and first adapter cylinders 71, 51.
b, 57c) and the other instruction mark 57a,
It is also possible to omit 57b, 57c (or 76a, 76b, 76c).

Further, at the position where the engaging pin 74 of the second adapter cylinder 71 has reached the end of the guide groove 54 of the first adapter cylinder 51, the first indicators 76a, 76 are displayed.
Second display 57a1, 57 corresponding to b, 76c
b1 and 57c1 are provided on the outer peripheral surface 58 on the base end side of the first adapter cylinder 51 provided with the guide groove portion 54 at three positions at approximately 120 ° intervals as in the case of the first display, and respectively as the indication marks. It is formed in the same mark shape (△, ○, □).

At the position where the engagement pin 74 is rotated and reaches the end of the groove 55 which is the engaged portion, the third indication 57a2, corresponding to the first indication 76a, 76b, 76c, is displayed. 57b2, 57c2 to the guide groove 54
On the outer peripheral surface 58 on the base end side of the first adapter cylinder 51 provided with the same as the above-mentioned first and second indications, at three positions at approximately 120 ° intervals, respectively, the same mark shape ( It is formed by △, ○, □).

In this way, the photographer takes three kinds of marks by providing at least three instruction marks for alignment display at substantially equal intervals on the peripheral surface of the first adapter cylinder 51 attached to the lens portion 40 on the camera body side. Shape (△, ○,
□) You will be able to see any of the above. Therefore, for example, the second adapter cylinder 7 is attached to the instruction mark 57a seen on the peripheral surface of the tip of the first adapter cylinder 51.
If the same instruction mark 76a on the peripheral surface of the base end portion of 1 is aligned and fitted, and the second adapter cylinder 71 is pushed in the optical axis direction (arrow direction) as shown in FIG. If 76a and the indication mark 57a1 which is the second display face each other, and then the second adapter cylinder 71 is rotated in the direction around the optical axis (arrow direction) as shown in FIG. 5C, The instruction mark 76a and the instruction mark 57a2 which is the third display
At the position where and face each other, the lock state is established and the fitting and mounting is completed.

By providing the positioning instruction marks as the first, second and third indications as described above, the first and second adapter cylinders can be locked reliably and smoothly, In addition, it has the advantage that the direction of removal can be seen at a glance when it is removed.

In the embodiment described above, the second adapter cylinder 71 is provided with the engagement pin 74 as an elastically displaceable engagement piece, and the first adapter cylinder 51 is provided with the guide portion and the engaged member. Although the engaging groove portions 54 and 55 that form the portion are provided, the present invention is not limited to this, and an elastically displaceable engaging piece is provided on the peripheral surface of the first adapter cylinder 51. Alternatively, the guide portion and the engaged portion may be provided by extending to the peripheral surface of the second adapter cylinder 71 on which the engaging piece is not provided.

[0069]

As described above, according to the present invention, it is possible to realize a lens adapter device in which an external lens can be easily attached to or detached from the camera body to replace the lens. Moreover, it is possible to realize a highly reliable lens adapter device without damaging the engaging member required for engaging or disengaging.

[Brief description of drawings]

FIG. 1 is a perspective view showing the outer appearance of a lens adapter device according to an embodiment of the present invention.

FIG. 2 is a vertical sectional view showing a main part of the lens adapter device of FIG.

FIG. 3 is a diagram showing a lens part, a first adapter,
Sectional drawing which expands and shows the joining state of a 2nd adapter, a protection adapter, and a tele-conversion lens, and the groove part for a rib, an engagement pin, a protection pin, and a guide.

FIG. 4 is a plan view illustrating the operation of the engagement pin and the protection pin of the second adapter when the second adapter is attached to or detached from the first adapter.

FIG. 5 is a perspective view showing an embodiment of an instruction mark used as an alignment display for mounting the first and second adapters.

[Explanation of symbols]

10 ... Lens adapter device 20 ... Electronic camera 30 ... Camera body 40 ... Lens storage section 50 ... First adapter 51 ... First adapter tube 54 ... Guide groove (first guide) 55 ... Engagement groove portion (engagement portion) 56 ... Guide groove (second guide) 60 ... Tele conversion lens (external lens) 70 ... Second adapter 71 ... Second adapter tube 72 ... Rib (specific portion) 74 ... Engaging pin (engaging piece) 75a, 75b ... long holes 78 ... Protection pin (protection piece) 80 ... Protection adapter 81 ... Protective tube

Claims (15)

[Claims] 1. A lens adapter device for connecting an external lens and a taking lens of a camera body, wherein the lens adapter device includes a first adapter tube having one end attached to the camera body, A second adapter cylinder in which an external lens is attached to one end portion, and the other end portion is fitted into and combined with the other end portion of the first adapter barrel that is not attached, and the first adapter barrel. Alternatively, an engaging piece that is elastically displaceable provided on the peripheral surface of any one of the second adapter tubes and a peripheral surface of the same adapter tube that is provided with the engaging piece A protective piece for protecting the engagement piece, which is provided at a portion closer to the connection end with the other adapter cylinder than the joint piece, and a peripheral surface of the adapter cylinder on which the engagement piece is not provided. The engaging piece that is extendedly provided And a guide portion for guiding the protection piece, and a guide portion provided on the peripheral surface of the adapter cylinder on which the engagement piece is not provided so as to be connected to the guide portion, and the engagement piece is biased and engaged. A lens adapter device comprising: 2. The engagement piece is planted in a specific portion formed in a portion of the peripheral surface so as to be easily elastically deformed by cutting out the periphery thereof. Lens adapter device. 3. The lens adapter device according to claim 2, wherein the specific portion is formed so as to be elastically deformable in the front-rear direction. 4. The engaged portion is formed so that an elastic displacement amount of the engaging piece is reduced at a terminal position of the engaged portion. The lens adapter device according to any one of claims. 5. The guide part comprises a first guide part for guiding the engagement piece and the protection piece in common, and a first guide part for further guiding the protection piece that has passed through the first guide part. 5. A second guide portion connected to the first guide portion, and the second guide portion.
Lens adapter device according to item 1. 6. The first guide portion is a groove portion formed in a direction substantially parallel to the optical axis, and the second guide portion and the engaged portion are formed substantially in the optical axis rotation direction. The lens adapter device according to claim 5, wherein the lens adapter device is a groove. 7. The lens adapter device according to claim 6, wherein a wall of the groove portion of the second guide portion is a wall for restricting a displacement amount of the engagement piece to a predetermined value or less. 8. The first guide portion is a groove formed by extending in the optical axis direction of the peripheral surface from the end surface of the adapter cylinder on which the engagement piece is not provided, and near the end surface entrance. The lens adapter device according to any one of claims 1 to 7, wherein the groove width is formed wider than the groove width extending to the peripheral surface. 9. The protective cylinder which covers the adapter cylinder provided with the engagement piece so as not to expose the engagement piece, is provided. Lens adapter device. 10. The lens adapter device according to claim 9, wherein the protection cylinder further covers the protection piece. 11. The first adapter barrel is configured so that its outer appearance does not fall within the field of view of the taking lens when only the first adapter barrel is connected to the camera body. Item 11. The lens adapter device according to any one of items 1 to 10. 12. The lens adapter device according to claim 1, wherein the engagement piece is a metal pin. 13. The lens adapter device according to claim 1, wherein the protection piece is a metal bottle. 14. The first adapter cylinder and the second adapter cylinder are provided with a plurality of combinations of the engagement piece, the guide portion and the engaged portion. The lens adapter device according to any one of claims 1 to 13. 15. A lens adapter device for connecting an external lens and a taking lens of a camera body, wherein the lens adapter device includes a first adapter tube having one end attached to the camera body, A second adapter cylinder in which an external lens is attached to one end portion, and the other end portion is fitted into and combined with the other end portion of the first adapter barrel that is not attached, and the first adapter barrel. Alternatively, an engaging piece provided so as to be elastically displaceable on the peripheral surface of any one of the second adapter tubes, and one provided with the engaging piece so as not to expose the engaging piece. A protective cylinder that covers the adapter cylinder, a guide portion that extends on the peripheral surface of the adapter cylinder that is not provided with the engagement piece, and that guides the engagement piece, and the engagement piece are provided. Circumference of the adapter tube In, provided connected to the guide portion, the lens adapter, characterized in that the engagement piece is provided with the engaged portion to be engaged is biased, the.