JPS6143684B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lens barrel capable of zoom photography and macro photography.

Conventionally, this type of lens barrel is known, for example, as disclosed in Japanese Patent Publication No. 10885/1985. The lens barrel disclosed herein has an operation ring that is rotated around the optical axis for zoom photography and that is slid in the optical axis direction for macro photography. When using this in a movie camera, a photographing method called focus shifting can be used. That is, first focus on a distant subject, then rotate the operating ring to perform zooming and fix the desired angle of view. Then, by starting photography and switching to macro photography by sliding the operating ring in the direction of the optical axis, the focal point can be shifted from a distant subject to a subject close to the lens. Of course, it is also possible to shift the focus from a nearby subject to a distant subject by performing the reverse operation. According to this, it is possible to smoothly and quickly determine the angle of view by zooming and change the focus without taking your hand off the operating ring. However, since the stroke of this operation ring in the optical axis direction is only small, it is difficult to continuously and gradually draw the focus point from a distant subject to a close subject, or to focus on a subject located between a far subject and a close subject. It was very difficult to focus.

It is an object of the present invention to provide zoom photography and macro photography in which the angle of view can be determined by zooming and the focus can be changed smoothly without taking your hand off the operating ring, and the focus can be changed continuously between distant and close subjects. The objective is to obtain a possible lens barrel.

An embodiment of the present invention will be described below with reference to the drawings.

A holding tube 3 that holds a focusing lens system 2 for performing focus adjustment is screwed onto the outer periphery of the left end of the fixed tube 1, and a fixed tube 3 that holds a focusing lens system 2 for adjusting the focus is screwed onto the inner periphery of the right end to direct the subject light to the captured image (not shown). A lens system 4 is fixedly installed. A first cam cylinder 5 is disposed on the outer periphery of the fixed cylinder 1, and a second cam cylinder 5, which functions as an operating ring, is disposed on the outer periphery of the cam cylinder 5.
The cam cylinders 6 are respectively arranged rotatably around the optical axis. First cam barrel 5 and second cam barrel 6
By engaging the pin 5a provided upright on the first cam barrel 5 and the straight groove 6a carved in the optical axis direction in the second cam barrel 6, rotation about the optical axis is performed as one unit. It rotates and is in a relatively slidable relationship with respect to linear movement in the optical axis direction.

A flange-shaped bearing portion 6b is fixed to the outer periphery of the second cam cylinder 6 by a screw 6c, and is erected in an axial direction perpendicular to the optical axis. A knob 7 is supported on the outer periphery of the bearing portion 6b, and a rotary shaft 7b fixed to the knob 7 with a screw 7a is supported on the inner periphery so as to be rotatable about an axis perpendicular to the optical axis. The rotating shaft 7b passes through the second cam barrel 6, and the eccentric cam 7c fixed to the lower end thereof is inserted into a rectangular hole 5b provided in the first cam barrel 5, as clearly shown in FIG. It is loosely inserted into. Further, a compression coil spring 8 is suspended between the first cam barrel 5 and the second cam barrel 6.
This spring 8 pushes the right end surface 6d of the second cam cylinder 6 into the first
Left side surface 5 of the flange portion provided on the left and right sides of the cam cylinder 5
Pressing on c. This defines the positional relationship between the first and second cam barrels 5 and 6 during normal photography (non-macro photography) shown in FIG.

A guide rod 1 extending in the optical axis direction is provided inside the fixed end 1.
a and 1b are spanned between the focusing lens system 2 and the fixed lens system 4. The guide rods 1a, 1b have first and second movable lens systems 9, 10, respectively.
A first retaining ring 11 and a second retaining ring 12 that retain
and both are slidably penetrated along the optical axis. A first cam pin 11a is erected on the outer peripheral surface of the first retaining ring 11, and this pin 11a passes through a straight groove 1c carved in the optical axis direction in the fixed barrel 1, and further extends through the first cam pin 11a. It fits into a first cam groove 5d carved in the cylinder 5. A second cam pin 12a is erected on the outer periphery of the second retaining ring 12, and this pin 12a is connected to the straight groove 1d of the fixed cylinder 1 and the first cam cylinder 5.
, and are fitted into second cam grooves 6e formed in the second cam cylinder 6. In the embodiment, the operation ring of the present invention includes the second cam cylinder 6
In addition, the zoom interlocking member corresponds to the first cam barrel 5 in the embodiment, and the macro interlocking member corresponds to the cam pin 12a in the embodiment.

First, the operation during normal zoom shooting will be explained. In FIG. 1, the first and second movable lens systems 9 and 10 are in a positional relationship when this lens barrel functions as a wide-angle lens with a wide angle of view. From this state, when the second cam barrel 6 is rotated around the optical axis by pinching the knob 7, the first cam barrel 5 also has a straight groove 6.
a, they rotate together through the connection of the pin 5a. Along with this rotation, the first and second cam grooves 5d, 6e
The first and second movable lens systems 9 and 10 are driven along both guide rods 1a and 1b via cam pins 11a and 12a. As the second cam barrel 6 rotates, the angle of view of the lens barrel gradually becomes narrower, until it finally functions as a telephoto lens. Of course, when photographing, it is necessary to focus on the desired subject by rotating the holding cylinder 3 in advance and displacing the focusing lens system 2 in the optical axis direction.

Next, the operation when using macro photography, particularly the focus shifting method, will be explained. When focusing on the desired subject is completed by rotating the holding barrel 3, and the desired angle of view is determined by rotating the second cam barrel 6 while pinching the knob 7, turn the knob 7 without taking your hand off. Rotates, or rotates, itself around an axis that is approximately perpendicular to the optical axis. Along with this rotation, the eccentric cam 7c
is in contact with the right side of the rectangular hole 5f shown in FIG.
Press the first cam cylinder 5 to the right. Then the first
Since the cam barrel 5 is integrally provided with the fixed barrel 1 in the optical axis direction, the second cam barrel 6, which is slidable in the optical axis direction, slides to the left against the biasing force of the spring 8. . As a result of this series of movements, the object that was previously in focus begins to blur, and the focal point gradually moves smoothly to a nearby object. and knob 7
When rotated by 180 degrees, the state shown in FIGS. 2 and 4 is reached, and the in-focus point shifts to a subject close to the lens barrel, resulting in a macro photography state. As explained above, the method of focusing is by rotating the knob 7.
After determining the angle of view by zooming, you can do it immediately and freely without taking your hands off, and you can stop when you focus on a subject located at an arbitrary distance.

In this embodiment, the first cam barrel 5 is disposed so as not to be slidable in the optical axis direction, and the second cam and 6 are disposed so as to be slidable, but the barrels are disposed in a reverse relationship. Also good. In this case, the cam groove 5d is provided in the second cam barrel 6, and the cam groove 6e is provided in the first cam barrel 5, and the rotation of the knob 7 displaces the first cam barrel 5 in the optical axis direction, causing the movable optical system 10 to move. This will enable macro photography.

FIG. 5 shows a partial cross-sectional view when the knob 7 is in the position shown in FIG. 1 during normal photographing. A click device consisting of a compression spring 13 and a rigid ball 14 is provided between the recess provided in the bearing portion 6b and the recess provided in the knob 7, so that the knob 7 may inadvertently rotate from the normal shooting state. It prevents you from doing it. Further, a pin 7d is implanted in the knob 7, and this pin 7d is inserted into a semicircular groove provided in the bearing portion 6b. This pin 7d
and the semi-circular groove form a rotation restriction, so that the knob 7 can reciprocate 180° one way, a total of 360° between the normal photographing position shown in Fig. 1 and the macro photographing position shown in Fig. 2. ing.

In this embodiment, the operating ring (second cam barrel 6) that pivotally supports the knob 7 for switching to macro photography is of the type that rotates around the optical axis for zooming. The invention is not limited to this. For example, a so-called one-hand zoom type in which zooming is performed by sliding in the direction of the optical axis and focusing is performed by rotating around the optical axis may also be used.

As is clear from the above description, according to the present invention, the angle of view is determined by a zoom operation by gripping the knob member pivotally supported by the operating ring and rotating the operating ring around the optical axis, and the zoom By rotating the knob member without taking your hand off the knob member in the photographing state, you can smoothly shift the focus for macro photography. Therefore, it has the advantage that macro photography can be performed smoothly from the zoom shooting state without taking your hand off the knob member, and it is possible to continuously focus from a distant subject to a close subject, and the lens mirror has good shooting operability. It is shaped like a cylinder. Furthermore, the lens barrel of the present invention allows macro photography by rotating the knob member even within the zoom operation range (on the other hand, with conventional lens barrels, the zoom operation range for zoom photography is within the zoom operation range). It was structured so that macro photography was possible by operating the camera to the end and then going beyond the operating range.) Therefore, the lens barrel of the present invention allows close-up photography to be performed immediately under any conditions, and allows quick operation.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an embodiment of the present invention during normal photography, FIG. 2 is a sectional view of the same embodiment during macro photography, and FIGS. 3 and 4 are sectional views of the same embodiment during normal photography and macro photography. A partial plan view at the time of photographing, and FIG. 5 shows a partial cross-sectional view of the same embodiment. Explanation of symbols of main parts, 6... Operating ring, 9, 1
1...Movable optical system, 7...Knob.

Claims (1)

[Claims] 1. Consisting of a plurality of movable zoom lenses that move during zoom shooting, and a part of the movable zoom lenses,
a movable lens for macro that moves during macro photography; a cam barrel having a first cam means for displacing the movable zoom lens other than the movable lens for macro; and a second cam means for displacing the movable lens for macro. is provided so as to fit on the outer periphery of the cam barrel, operates integrally with the cam barrel in the direction of rotation around the optical axis, and moves relative to the cam barrel in the direction of the optical axis. an operating ring; an operating ring protruding from the outer peripheral surface of the operating ring so as to be rotatable;
The knob member has a means for relatively moving the operating ring and the cam barrel in the optical axis direction by rotation of the knob member, and the operating ring and the cam barrel are integrally rotated during zoom shooting. The zoom movable lens is moved in a predetermined relationship, and during macro photography, the operating ring and the cam barrel are moved relative to each other in the optical axis direction in accordance with the rotation of the knob member to move the macro movable lens. A lens barrel characterized by being configured as follows.