JPH09211657A - Lens interchange system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detach a lens cap only by one hand holding a lens-barrel and mount the cap on the lens-barrel by one hand operation by operating a release means so as to release engagement of the release means with an engaging means. SOLUTION: When a mounted rear side lens cap 1 is detached from a lens- barrel 7, the rear side lens cap 1 is set downward, and the lens-barrel 7 is let stand up on a placing surface 25. While holding the lens-barrel 7 with one hand, push buttons 19 are oppositely pinched with two fingers, for example, with the thumb and the forefinger, and pressing force is applied. Then plate springs 13 are bent, the extreme end parts 18 are retracted, and engagement between claws 15 and engaging parts 24 through hook faces 16 is released. Next the lens-barrel 7 is straightly elevated upward. The rear side lens cap is subjected to gravity, it is smooth and almost frictionless between cylindrical parts 21, 8, and hence the rear side lens cap 1 is detached and left on the placing surface 25. Thus, the cap can be detached and mounted by only one hand.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an interchangeable lens. Above all, the present invention relates to an interchangeable lens in which a rear lens cap is detachably provided on the camera mount side.

[0002]

2. Description of the Related Art A conventional interchangeable lens which is detachably attached to a camera is protected by a front lens cap and a rear lens cap which are attached to the front and rear of a lens cap barrel when not attached. To replace the lens, attach the front lens cap to the lens barrel you are using, remove the lens barrel from the camera, attach the rear lens cap to the camera mount side, and store it in the trunk. Then, the other lens barrel stored in the trunk is taken out from the trunk, the rear lens cap is removed, the lens barrel is attached to the camera, and the front lens cap is removed.

The conventional lens mount and camera mount of the lens barrel according to the bayonet system are shown in FIGS.
It was as shown in The rear lens cap 1 is formed of a cylindrical portion 2 and a bottom portion 3, and an end surface of the cylindrical portion 2 is an abutting surface 4 parallel to the bottom portion 3. Three protrusions 5 are provided axially symmetrically along the inner circumference of the cylindrical portion 2, and three notches 6 are provided between the protrusions 5. The lens mount 7 has a cylindrical portion 8 on the camera mount side, and the protrusions 9 are provided at three axially symmetrical locations along the outer periphery between the mount surface 10 and the tip 11 of the cylindrical portion 8. There are three notches 12 between the portions 9. When the rear lens cap 1 is attached to the lens barrel 7, first, the projection 5 of the rear lens cap 1 and the notch 12 of the lens barrel 7 face each other, that is, the notch of the rear lens cap 1. The portion 6 and the protrusion 9 of the lens barrel 7 are made to face each other. When the cylindrical portion 8 of the lens barrel 7 is fitted into the cylindrical portion 2 of the rear lens cap 1 until the abutting surface 4 contacts the mount surface 10, the tip portion 11 approaches the bottom portion 3 very close. The rear lens cap 1 is rotated with respect to the lens barrel 7 until it abuts against a stopper (not shown). The projection 5 faces the projection 9 of the lens barrel 7 between the projection 5 and the bottom 3 of the rear lens cap 1, and the rear lens cap 1 is held by the lens barrel 7.

Another conventional technique is to engage a rear lens cap with a lens barrel by means of a rotary screw. In another conventional technique, the rear lens cap is engaged with the lens barrel by frictional force.

[0005]

As described above, in the conventional technology for engaging the rear lens cap with the bayonet type lens barrel, it is necessary to rotate the lens barrel and the rear lens cap with respect to each other. It was This operation can be achieved by holding one of them with one hand and the other with the other hand. That is, it is an operation of using both hands at the same time. A photographer who exchanges and uses a plurality of interchangeable lenses often carries not only a camera but also several interchangeable lenses and many other equipment, and holds them by hand. The normal lens replacement operation is performed as follows. Hold the camera in one hand and the lens barrel in the other hand and rotate it to remove. Put the camera away from your hand in a trunk or other container or desk near you, hold the rear lens cap in your hand, face the lens barrel in your other hand, and rotate it to put it on. Alternatively, the lens barrel may be changed and then operated. After mounting, store the lens barrel in the trunk, take out the other lens barrel, and use both hands to remove the rear lens cap.
As described above, the conventional technology using the bayonet system has a problem that it requires a rotating operation using both hands for attachment and detachment, which is extremely inconvenient.

The rotary screw method or the friction method also requires a detaching operation using both hands, which is very inconvenient.

In view of the above problems, it is an object of the present invention to provide an interchangeable lens in which the lens cap can be removed only by the hand holding the lens barrel. Another object of the present invention is to provide an interchangeable lens system in which the lens cap can be mounted on the lens barrel with one hand.

[0008]

According to the present invention, in an interchangeable lens system comprising a lens barrel and a lens cap, a holding means and a releasing means provided on the lens barrel and a member provided on the lens cap. The holding means is engageable with the engaging means, and the releasing means releases the engagement between the holding means and the engaging means by operating the releasing means. This constitutes an interchangeable lens system. The lens cap is more effective when it is a rear lens cap attached to the camera mount side of the lens barrel. A guide means is formed in the holding means, and the guide means engages the holding means by abutting the lens cap when the lens barrel moves straight to a predetermined position facing the lens cap. It is preferable to evacuate from the coupling means. In an interchangeable lens including a lens barrel and a lens cap, a leaf spring provided on the lens barrel and provided with a hooking claw, a push button, and a guide portion and a hooking portion provided on the lens cap are provided. When the lens barrel and the lens cap are opposed to each other and move straight, the lens cap abuts against the guide portion and presses the leaf spring to bend the leaf spring to hook the hook claw. When the hooking claw reaches the position of the hooking part, the retracting is released, the hooking claw engages with the hooking part, and while holding the lens barrel with one hand, It is desirable to release the engagement by pressing the push button with only one hand and bending the leaf spring to retract the hooking claw from the hooking portion.

[0009]

FIG. 1 shows a first embodiment of the present invention.
This will be described with reference to FIG. As shown in FIG. 1, the rear lens cap 1 is attached to the lens barrel 7. Two leaf springs 13 are fixed to the cylindrical portion 8 of the lens barrel 7 by screws 14 at axially symmetrical positions on the inner peripheral side. Leaf spring 13
Extends toward the mount surface 10 side in the lower part of the drawing, and a claw 15 is provided at the tip thereof so as to project toward the outer peripheral side of the cylindrical portion 8. The claw 15 is formed with an upward catching surface 16 and a downward outward slope 17. The tip portion 18 of the claw 15 projects from the outer peripheral surface of the cylindrical portion 8 when no external force is applied. A push button 19 is provided between the portion of the leaf spring 13 fixed by the screw 14 and the claw 15. The push button 19 has a hole 2 formed in the cylindrical portion 8.
It is possible to penetrate through the cylinder 0 and press from the outside of the cylindrical portion 8 toward the inside. The leaf spring 13 bends when the push button 19 is pressed, and the claw 15 can retract inside the cylindrical portion 8 in the drawing. The tip of the cylindrical portion 8 on the camera mount side is a tip portion 11.

The rear lens cap 1 is composed of a cylindrical portion 21 and a bottom portion 22. The inner diameter of the cylindrical portion 21 is larger than the outer diameter of the cylindrical portion 8 of the lens barrel 7, and the cylindrical portion 8 has the tip portion 1
It can be inserted smoothly from the 1 side with almost no friction. The abutting surface 2 is located at a position near the bottom 22 on the inner circumference of the cylindrical portion 21.
3 is formed so that it can come into contact with the mount surface 10 of the lens barrel 7. An engaging portion 24 is provided at a position farther from the bottom portion 22 on the inner circumference of the cylindrical portion 21 so as to face the bottom portion 22 and can engage with the claw 15.

Next, the operation will be described. When the rear lens cap 1 is attached to the lens barrel 7, the rear lens cap 1 is placed on the mounting surface 25 so that the bottom portion 22 is downward and the cylindrical portion 21 is opened upward. Mounting surface 25
Is a flat, upward-facing plane such as a trunk or other container or desk at hand. The lens barrel 7 is gripped with one hand, and the tip portion 11 side is made to face downward so as to face the cylindrical portion 21, and is lowered straight downward, that is, in the direction C in FIG. The cylindrical portion 8 of the lens barrel 7 is fitted into the cylindrical portion 21 to be in the state shown in FIG. Since the tip portion 18 of the claw 15 projects to the outer peripheral side of the cylindrical portion 8, the slope 17 contacts the upper end of the cylindrical portion 21. When the lens barrel 7 is further lowered, the flat surface 13 is bent by being pressed by the cylindrical portion 21 by the inclined surface 17, and the inclined surface 17 guides the cylindrical portion 21 while retracting to the inner peripheral side of the cylindrical portion 8. Cylindrical part 21
When the mount surface 10 is lowered until it abuts against the abutting surface 23, the tip end portion 18 of the claw 15 reaches the engaging portion 24, and the pressing of the inclined surface 17 retracted from the cylindrical portion 21 is released,
The shape of the leaf spring 13 is restored. The tip portion 18 projects to the outer peripheral side of the cylindrical portion 8, and the hooking surface 16 engages with the engaging portion 24.
In the state shown in FIG. 1, the rear lens cap 1 is thus stably mounted by being locked to the mount surface 10 and the hooking surface 16 of the lens barrel 7 at the abutting surface 23 and the engaging portion 24. It is in a state of being.

When the mounted rear lens cap 1 is removed from the lens barrel 7, the lens barrel 7 is placed upright on the mounting surface 25 with the rear lens cap 1 facing down. While holding the lens barrel 7 with one hand, press the push button 19 with two fingers, for example, the thumb and the forefinger, and use the arrows A and B in FIG.
And press them against each other. Then, the leaf spring 13 bends, the tip portion 18 retracts, and the engagement between the claw 15 and the engaging portion 24 by the hooking surface 16 is released. The lens barrel 7 is lifted straight upward. Gravity acts on the rear lens cap 1, and there is little friction between the cylindrical portion 21 and the cylindrical portion 8, so that the rear lens cap 1 is left on the mounting surface 25 after being removed. Alternatively, the same applies when the lens barrel 7 is gripped and the mounting surface 25 is lowered straight downward. Further, if the push button 19 is operated almost directly above the trunk or bag with the lid opened, the rear lens cap 1 will drop and come off, so that the purpose of removal can be achieved.

In the present embodiment, the hooking method of engaging with the claw and the hooking surface is used, but the present invention is not limited to this, and a method of utilizing frictional force, magnetic force or the like may be used.

Although the present embodiment is composed of a pair of claws, a hooking surface, and a push button, it is not limited to one pair and may be composed of one piece for each.

[0015]

With the interchangeable lens of the present invention, the lens cap can be removed from the lens barrel with only one hand. Furthermore, the lens cap can be attached to the lens barrel with only one hand.

[Brief description of drawings]

FIG. 1 is a sectional view of an interchangeable lens to which a lens cap according to a first embodiment is attached.

FIG. 2 is a cross-sectional view of an interchangeable lens for explaining an operation of mounting the lens cap according to the first embodiment on a lens barrel.

FIG. 3 is a cross-sectional view of the interchangeable lens for explaining the operation of removing the lens cap according to the first embodiment from the lens barrel.

FIG. 4 is a sectional view of a conventional lens cap.

FIG. 5 is a plan view of a conventional lens cap.

FIG. 6 is a plan view of a conventional lens barrel.

FIG. 7 is a cross-sectional view of an interchangeable lens to which a conventional lens cap is attached.

[Explanation of symbols]

 1 ... Rear lens cap 2 ... Cylindrical portion 4 ... Abutting surface 7 ... Lens barrel 8 ... Cylindrical portion 10 ... Mounting surface 13 ... Leaf spring 15 ... Claw 16 ... Hooking surface 17 ... Slope 19 ... Push button 21 ... Cylindrical part 23 ... Abutting surface 24 ... Engagement part

Claims (4)

[Claims] 1. An interchangeable lens system comprising a lens barrel and a lens cap, comprising: holding means and releasing means provided on the lens barrel, and engagement means provided on the lens cap, The holding means is engageable with the engaging means, and the releasing means releases the engagement between the holding means and the engaging means by operating the releasing means. . 2. The interchangeable lens system according to claim 1, wherein the lens cap is a rear lens cap mounted on the camera mount side of the lens barrel. 3. The holding means is formed with a guide means, and the guide means contacts the lens cap when the lens barrel moves straight to a predetermined position facing the lens cap. The interchangeable lens system according to claim 1, wherein the means is retracted from the engagement means. 4. An interchangeable lens system comprising a lens barrel and a lens cap, wherein the lens barrel is provided with a leaf spring having a hooking claw, a push button and a guide portion, and the lens cap. When the lens barrel and the lens cap are opposed to each other and go straight ahead with each other, the lens cap abuts and presses against the guide portion to bend the leaf spring and When the hooking claw is retracted from the hooking part, and when the hooking claw reaches the position of the hooking part, the retracting is released and the hooking claw engages with the hooking part to hold the lens barrel with one hand. The interchangeable lens system is characterized in that the engagement is released by pressing the push button with only one hand while flexing the leaf spring to bend the leaf spring to retract the hooking claw from the hooking portion while gripping with.