JPH05142637A - Interchangeable lens barrel - Google Patents

Abstract

PURPOSE:To obtain a lens barrel suitable for shift or tilt by providing a conversion means for converting the movement of an automatic lever on a camera side into an electrical signal and an electric driving signal for controlling the stop blade of the interchangeable lens according to a signal from the conversion means. CONSTITUTION:Positional information in a diaphragm ring 22 is linked with a diaphragm value transmitting lever 23 to engage with the diaphragm information lever 12 of the camera main body 10, and is transmitted to the exposure control mechanism 15 of a camera main body 10 through an electrical signal generating mans 13. The positional information detected by an electrical signal generating means 24 is transmitted to a motor control circuit 25. A stop-down lever 26 engaging with a diaphragm lever 11 is moved by actuating the lever 11, and a moving amount is detected by an electrical signal generating means 27 and transmitted to a motor control circuit 25. The motor control circuit 25 controls a motor 28 for diaphragm is controlled according to the positional information on the lever 23 and the information on the moving amount of the lever 26, and a diaphragm mechanism 29 is converged from opening to a specified diaphragm value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an interchangeable lens barrel used for a single-lens reflex camera, and more particularly to an interchangeable lens barrel suitable for an orienting lens such as shift, swing and tilt which can be used in open photometry.

[0002]

2. Description of the Related Art In principle, the optical axes of lenses are orthogonal to each other at the center of the screen.
It is called a tilt and is used to correct the deformation of the image and to focus on the entire slope. When shooting a building such as a skyscraper, the building will be deformed if you shoot it with the camera facing up, but there is a shift lens etc. that can prevent the deformation by keeping the camera horizontal and moving the shooting lens in parallel vertically and horizontally. Has been.

Many large cameras have a tilt mechanism, but there are few interchangeable lenses having a tilt mechanism in a single-lens reflex camera. This is because the interchangeable lens of a single-lens reflex camera must be devised with a lens barrel having various interlocking mechanisms such as a diaphragm mechanism, and the arrangement configuration of the optical system is limited.

[0004]

The tilt lens has to move or tilt the optical system vertically and horizontally with respect to the camera body, and the mechanism related to the automatic diaphragm moves vertically or horizontally and tilts. Since the mechanism becomes complicated, it is common to integrate the camera body with the mount part that mounts the interchangeable lens, and as a result, the optical system must be placed in front of the interchangeable lens and the degree of freedom in optical design is limited. It had been.

[0005]

[Means for Solving the Problem] The exposure of a subject is determined with the photographic lens aperture open, and the iris of the photographic lens is moved to the planned aperture position by operating the squeezing lever on the camera side linked to the shutter release of the camera. In the interchangeable lens used for the open metering camera, the conversion means for converting the movement of the camera side auto lever into an electric signal and the electric drive means for controlling the diaphragm blade of the interchangeable lens by the signal from the conversion means are provided. The above problem was solved.

[0006]

The converting means converts the movement of the camera side auto lever into an electric signal. The electric driving means for controlling the diaphragm blades of the interchangeable lens moves up and down and to the left and right integrally with the optical system, and adjusts the diaphragm blades to a predetermined aperture by a signal from the converting means.
Proper exposure is given to the film surface.

[0007]

EXAMPLES The present invention will be described below with reference to examples.

FIG. 3 is a schematic view showing an exposure control mechanism of a camera to which the interchangeable lens of the present invention is attached. In the figure, a diaphragm lever 11 is provided which is linked to the diaphragm of the interchangeable lens,
A drive lever 31 that engages with the aperture lever 11 is pivotally supported together with a fan gear 32 by a pivot 33a. Start lever 3 linked with shutter release
4 is operated, the fan-shaped gear 32 meshing with the small gear 35a is connected to the large gear 35b integrally formed with the small gear 35a.
Is configured to rotate. A ratchet wheel 36 is provided with a notch hole 36a, and a large gear 35b is provided at the center thereof.
A small gear 36b that meshes with the
It is pivotally supported by b. A transducer 37 is arranged in the cutout hole 36a of the ratchet wheel 36, and measures the pulse generated by the cutout hole 36a generated by the rotation of the ratchet wheel 36.
The rotation amount of 6 is obtained. When this rotation amount reaches a value corresponding to an appropriate aperture value, the electromagnet 39 releases the attraction of the braking lever 40 by a signal from the stop signal generation circuit 38,
The engaging claws 40a of the braking lever 40 are configured to engage with the teeth of the ratchet wheel 36 and stop the ratchet wheel 36.
Thereby, the small gear 36b, the large gear 35b, the small gear 35
a, the fan-shaped gear 32, and the drive lever 31 are stopped, and the movement of the aperture lever 11 is stopped. And the aperture lever 11
The aperture lever of the interchangeable lens also stops via. As a result, a proper aperture is obtained, and then the shutter operates to expose the light, and the photographing is completed.

FIG. 1 is a block diagram showing the outline of the present invention.
Reference numeral 10 denotes a camera body, to which an interchangeable lens 20 is attached. In the camera body 10, an aperture lever 11 that operates the aperture of the interchangeable lens 20 at the time of shooting, an electric signal generating unit 13 that converts information of an aperture information lever 12 that detects a set aperture of the interchangeable lens 20 into an electric signal, and a brightness measuring unit. 14 is connected to the exposure control mechanism 15. The interchangeable lens 20 has a focus ring 2 for moving an optical system for focus adjustment.
1. An aperture ring 22 for setting an aperture value is provided, and the aperture ring 22 is linked with an aperture value transmission lever 23 and engages with an aperture information lever 12 of the camera body 10, and an exposure control mechanism of the camera body 10. 15 is an electric signal generating means 1
The set aperture value is transmitted via 3. Further, the positional information of the aperture value transmission lever 23 is similarly detected by the electric signal generating means 24 in the interchangeable lens 20 and sent to the motor control circuit 25.

On the other hand, the diaphragm lever 26 engaged with the diaphragm lever 11 of the camera body 10 is moved by the operation of the diaphragm lever 11, and the amount of movement is detected by the electric signal generating means 27. The detected movement amount information is the aperture value transmission lever 2
It is sent to the motor control circuit 25 in the same manner as the position information of No. 3.
The motor control circuit 25 controls the diaphragm motor 28 based on the position information of the diaphragm value transmission lever 23 and the movement amount information of the diaphragm lever 26, and narrows the diaphragm mechanism 29 from the open state to the designated diaphragm value.

The diaphragm motor 28 includes a section 30a and a section 30.
It is connected to the motor control circuit 25 by b. The sections 30a and 30b have a length equivalent to the amount of movement for shifting the interchangeable lens 20, and as shown in FIG. 2, the sections 30a and 30b are always electrically connected even during shifting.

FIG. 4 is a schematic diagram showing the electric signal generating means. Reference numeral 26 is a lens-side stop lever that engages with the camera-side stop lever, and is fixed to the auto ring 41 that rotates along the circumference of the lens barrel. A sliding terminal 42 is fixed to the auto ring 41, and the sliding terminal 42 has a resistor 43.
The resistor 43 is moved on the resistor 43 from the position in sliding contact with the end to the end to which the first detection terminal 44 is connected. The sliding terminal 42 moves on the section 46 toward the end to which the second detection terminal 45 is connected. As a result, the first detection terminal 4
4, an electrical signal indicating the displacement of the auto lever is output depending on the resistance value between the second detection terminal 45.

In this embodiment, the resistor is used to describe the electric signal generating means, but it may be generated digitally by counting pulses.

[0014]

In the tilt lens, the optical system has to be moved in parallel in the vertical and horizontal directions with respect to the camera body, and tilted.
The mechanism related to the automatic diaphragm is complicated if it is moved up and down, left and right in parallel, or tilted. A conversion means for converting the aperture blades to the optical system is provided integrally with the optical driving means for controlling the aperture blades of the interchangeable lens, and the aperture blades are electrically adjusted to a predetermined aperture, so that the arrangement of the optical and aperture mechanisms can be freely performed. Becomes
The degree of freedom in optical design can be increased.

[Brief description of drawings]

FIG. 1 is a block diagram showing an outline of the present invention.

FIG. 2 is a block diagram showing an outline during a shift.

FIG. 3 is a schematic view showing an exposure control mechanism of a camera to which an interchangeable lens is attached.

FIG. 4 is a schematic view showing an electric signal generating means.

[Explanation of symbols]

 10 Camera Main Body 11 Aperture Lever 12 Aperture Information Lever 13 Electric Signal Generating Means 14 Luminance Measuring Means 15 Exposure Control Mechanism 20 Interchangeable Lens 21 Focus Ring 22 Aperture Ring 23 Aperture Value Transmission Lever 24 Electric Signal Generating Means 25 Motor Control Circuit 26 Aperture Lever 27 Electrical signal generating means 28 Aperture motor 29 Aperture mechanism

Claims (1)

[Claims] 1. An open metering system in which the exposure of a subject is determined with the photographic lens diaphragm open, and the photographic lens diaphragm is operated to a predetermined diaphragm position by the operation of a camera side squeezing lever linked to the shutter release of the camera. An interchangeable lens for use in a camera, characterized in that the interchangeable lens is provided with conversion means for converting movement of a camera-side auto lever into an electric signal and electric drive means for controlling diaphragm blades of the interchangeable lens according to a signal from the conversion means. Lens barrel.