JPH0412497Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a mirror mechanism for a single-lens reflex camera equipped with a main mirror and an auxiliary mirror.

(Conventional technology and issues) A main mirror and an auxiliary mirror are used for TTL photometry and objective lens focus detection, and light from the objective lens is directed to a photoelectric element placed at a position equivalent to the film surface inside the camera. A guiding mirror mechanism has been proposed and implemented.

Particularly in the latter case of focus detection, it is an absolute requirement to keep the light-receiving surface of the light-receiving element in a position optically equivalent to the film surface, and for this purpose it is necessary to maintain the angle of each mirror accurately. becomes.

In the former case, it is not required to be very precise, but it goes without saying that it is better to maintain the mirror position and angle accurately.

The purpose of this invention is to provide a mirror mechanism for a single-lens reflex camera that has a simple structure and operates reliably, and is suitable for TTL photometry and objective lens focus detection.

(Means for Solving the Problems) In order to achieve the above object, the mirror mechanism of the single-lens reflex camera according to the present invention supports a main mirror having a partially translucent part and raises the mirror to a position at 45° with respect to the optical axis. a main mirror frame that is movable between positions; and an auxiliary mirror that is pivotally supported by the main mirror frame and guides the light that has passed through the main mirror to a position equivalent to the film surface, and supports the observation position and the back surface of the main mirror. an auxiliary mirror frame that moves between photographing positions in contact with the auxiliary mirror frame, a protrusion provided on a side surface of the auxiliary mirror frame, a main mirror position regulating member that regulates the main mirror frame to the 45° position, and the auxiliary mirror frame. an auxiliary mirror position regulating member that regulates the frame to the observation position; a rotary lever provided with a long hole that engages with a protrusion of the auxiliary mirror frame and pivoted coaxially with the main mirror frame; and the auxiliary mirror. urging the rotating lever so that the frame abuts against the auxiliary mirror position regulating member through a protrusion that engages with the elongated hole, and the main mirror frame abuts against the main mirror position regulating member; a biasing member, and driving the rotary lever by applying a rotational upward force to the rotary lever;
and a drive mechanism that drives the main mirror to a photographing position as the auxiliary mirror frame moves from the observation position to a photographing position in contact with the back surface of the main mirror.

(Description of Embodiments) The mirror mechanism of the single-lens reflex camera according to the present invention will be described in more detail below with reference to the drawings and the like.

Fig. 1 is a perspective view showing an embodiment of the mirror mechanism according to the present invention, Figs. 2 and 3 are side views for explaining the operation, and Fig. 2 shows the main mirror at a 45° position;
An auxiliary mirror is shown in the observation position.

FIG. 3 shows each mirror in a raised position. The main mirror 1 is a mirror that is at least partially semitransparent, and can partially transmit a portion of the light from the objective lens 15 to the rear. This mirror 1 is supported by a main mirror frame 2, and a portion of the main mirror frame 2 corresponding to the auxiliary mirror 4 is open.

The main mirror frame 2 is rotatably supported by the main shaft 3 through holes 2a and 2b. The auxiliary mirror 4 is supported by an auxiliary mirror frame 5, and the auxiliary mirror frame 5 is supported by a shaft 14.
It is rotatably supported with respect to the main mirror frame 2.

The rotary lever 7 is also rotatably supported by the main shaft, and has a bent line-shaped elongated hole 7a at one end. This elongated hole 7a is engaged with a pin (projection) 6 set up on the auxiliary mirror. Although the long hole of the rotary lever that engages with the pin 6 of the auxiliary mirror frame 5 is bent into a curved shape, there is no problem even if it is a gentle curve.

The shape of this elongated hole is chosen to facilitate pushing up from the position shown in FIG.

A spring 8 is installed between the pin 7b installed on the rotating lever 7 and other pins installed at fixed positions.
is provided, and the rotation lever 7 is rotated by this spring.
is biased counterclockwise.

A pin 11 is provided on the other side of the rotary lever 7, and a force for rotating and raising the rotary lever 7 is applied via this pin 11 from a drive mechanism (not shown).

Although this rotary lever 7 is a part machined from a single flat plate, the portion connecting the left and right sides is shown broken in FIG.

The auxiliary mirror positioning pin 9 is an auxiliary mirror position regulating member that regulates the auxiliary mirror 4 to the observation state position. Note that this pin 9 is fixed to the mirror box with an eccentric pin or the like. The contact position between this pin 9 and the auxiliary mirror frame 5 can be adjusted. The main mirror positioning pin 10
This is a main mirror position regulating member that regulates the position to 45°.
This pin 10 is also attached to the main mirror frame 2 in the same way as the pin 9.
The contact position can be adjusted.

Reference numeral 12 shown in FIGS. 2 and 3 is a buffer member such as Moltoprene. A photoelectric element 13 is provided below the mirror box with its light-receiving surface facing upward. 16 indicates a focal plane shutter.

Next, the operation of the mechanism will be explained mainly with reference to FIGS. 2 and 3.

In the observation state shown in FIG. 2, the rotational force of the rotation lever 7 by the spring 8 (biasing member) is applied to the auxiliary mirror frame 5 in a counterclockwise direction due to the engagement of the elongated hole 7a of the rotation lever 7 with the pin 6 of the auxiliary mirror. Gives rotational force.

This force is transmitted to the main mirror frame 2 as a force that rotates the main mirror 1 counterclockwise.

The main mirror frame 2 is abutted against a pin 10, and the auxiliary mirror frame 5 is abutted against a pin 9, so that their respective positions are regulated.

To adjust the angular position of this mirror, first, the correct position and angle of the main mirror 1 is obtained using the pin 10, and then the angle of the auxiliary mirror is adjusted using the pin 9.

When the release mechanism (not shown) is operated, a rotational lifting force is transmitted to the pin 11 of the rotary lever 7 by the drive mechanism (not shown), and the rotary lever 7 is pushed up in the clockwise direction before the shutter 16 moves.

This movement of the lever 7 is transmitted to the auxiliary mirror frame 5 via the auxiliary mirror pin 6, and the auxiliary mirror 4 is pushed up.

As this auxiliary mirror 4 rises, the main mirror frame 2
The rotation is also increased to reach the state shown in FIG. 3, and the rotation increase is completed.

The impact after the rotation has finished rising is absorbed by the buffer member 12.

When the shutter operation is completed, the restraining force applied to the pin 11 is removed, and each mirror returns to the position shown in FIG. 2 by the energy of the spring 8 accumulated by the above-mentioned rotational increase.

(Effects of the Invention) As explained above in detail, the mechanism according to the present invention is extremely simple, but it can give accurate positions to each mirror.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of a mirror mechanism according to the present invention. FIG. 2 is a side view showing the mirror in the lowered position, and FIG. 3 is a side view showing the mirror in the raised position. 1...Main mirror, 2...Main mirror frame, 3...Main axis, 4...Auxiliary mirror, 5...Auxiliary mirror frame, 6
...Auxiliary mirror pin, 7...Rotation lever, 8...
Spring (biasing member), 9... Auxiliary mirror positioning pin (auxiliary mirror position regulating member), 10... Main mirror positioning pin (main mirror position regulating member), 11
... Pin, 12 ... Buffer member, 13 ... Photoelectric element, 15 ... Objective lens, 16 ... Shutter.

Claims (1)

[Claims for Utility Model Registration] A main mirror with a partially translucent part is supported and aligned with the optical axis.
A main mirror frame that can be moved between a 45° position and an elevated position, and an auxiliary mirror that is pivotally supported by the main mirror frame and guides the light transmitted through the main mirror to a position equivalent to the film surface are supported to adjust the observation position. and an auxiliary mirror frame that moves between photographing positions in contact with the back surface of the main mirror; a protrusion provided on a side surface of the auxiliary mirror frame; and a main mirror position regulation that regulates the main mirror frame to the 45° position. an auxiliary mirror position regulating member for regulating the auxiliary mirror frame to the observation position; and a rotating member provided with an elongated hole that engages with a protrusion of the auxiliary mirror frame and pivoted coaxially with the main mirror frame. a lever, and the rotation so that the auxiliary mirror frame abuts against the auxiliary mirror position regulating member via a protrusion that engages with the elongated hole, and the main mirror frame abuts against the main mirror position regulating member. a biasing member that biases the lever; and a biasing member that applies a rotational upward force to the rotary lever to drive it;
A mirror mechanism for a single-lens reflex camera comprising: a drive mechanism that drives the main mirror to a photographing position as the auxiliary mirror frame moves from the observation position to a photographing position in contact with the back surface of the main mirror.