JPH0338625A - Motor-driven focusing photographing device - Google Patents

Abstract

PURPOSE:To obtain the focusing photographing device of simple constitution which performs focusing, opens and closes its shutter, and drives it to return to an initial position by using a ratchet gear for photographic lens driving which is driven intermittently by a ratchet claw and also energized in the opposite direction from the intermittent driving. CONSTITUTION:When a stepping motor 1 rotates clockwise one step, the ratchet claw 7b pushes and rotates a ratchet tooth 9a of the ratchet gear 9 clockwise against a spring 9b. Then when the motor 1 reverses by one step, the tooth returns to its original position. The operation is performed until a focusing signal generates to rotate the ratchet gear 9, thereby putting the photographic device in focus. When the motor is reversed after the focusing, a lever 11 rotates counterclockwise and a shutter blade 12 is opened. The shutter is closed by reversing the motor. The gear 6 is rotated counterclockwise greatly by subsequent large clockwise rotation of the motor, and the claw 7b is separated from the ratchet tooth 9a, so the ratchet gear returns to its initial position with the force of the spring 9b.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an automatic focusing camera, and more particularly to a camera having a mechanism for returning the photographing lens to its initial position after opening and closing the shutter shutter after focusing. 2. Description of the Related Art A lens is intermittently driven in a first direction via a first partially toothed gear, and a lens is intermittently driven in a second direction via a second partially toothed gear. A lens driving device that automatically focuses by being driven has been proposed (Patent Publication No. 1)
-22602).

``Problems to be Solved by the Invention'' In the above-mentioned prior art, the focusing mechanism and shutter mechanism are independent, resulting in a complicated shutter configuration.

"Means and Effects for Solving the Problems" The present invention aims to perform focusing, opening/closing the shutter, and driving the return to the initial position with a simple configuration, and uses a reciprocating drive of a stepping motor in one to a small number of steps. By repeating the intermittent drive in the first rotational direction, and by the switch mechanism provided in the small transmission part of the drive driven by the DC motor, the intermittent drive in the first direction by one rotation and one reciprocating rotation is performed. By repeatedly reciprocating the ratchet pawl, the helicoid is driven to focus via the ratchet tooth ring provided on the circumference of the photographic lens until a focusing signal is generated or by a pre-measured amount, and then the motor is activated. The reciprocating drive of the predetermined rotation in the second rotation direction drives the e-shutter to open and close, and the subsequent large rotation drive in the first direction removes the ratchet pawl from the ratchet tooth ring and urges this ring in the return direction. To provide a focusing photographing device configured and operated to return to its original position on a spring.

Embodiment FIGS. 1 to 5 show embodiments of the present invention, and the same members in FIG. Kb are designated by the same numbers. Figure 1 shows the configuration of this device in its initial state. is a rotation support shaft of the sector gear 6. 7 and 8 are ratchet claw levers; 9 is a ratchet gear for driving the helicoid of the photographing lens; IO and 11 are shutter drive levers; 12 is a shutter blade.

Only one of the two shutter blades is shown.

Next, the operation will be explained using figures. FIG. 1 shows the initial state. If the motor 1 is a stenobing motor, when the motor 1 is rotated clockwise by l steps (or several stenobbings, the same applies hereinafter), the partially toothed gear 5 is turned clockwise via the gears 2, 3, and 4. The sector gear 6 rotates counterclockwise around the support shaft 6a, and the ratchet pawl lever 7 pushes out the support shaft 7a supported by the sector gear 6 in the direction of the arrow, and the ratchet pawl 7b is the ratchet tooth 9a of the ratchet gear 9 with the spring 9bl/i:
Push it clockwise against the pressure. In this state, the ratchet pawl 8b of the ratchet pawl lever 8 passes over the teeth of the ratchet gear 9 and locks the next ratchet m with the force of the spring 8C. Next, when the motor 1 rotates one step in the opposite direction, the ratchet pawl lever 7 resists the spring 7dlC, passes over the teeth of the ratchet gear 9, and returns to its original position. The above operation is continued until a focus signal is generated or by a pre-measured amount, that is, the ratchet gear 9 is rotated by 4 steps A0 to A4 as shown in FIG. . FIG. 2 shows the feeding status of the ratchet gear 9 during this period. In addition, switches SW1 and SW shown in FIG.
This is to perform the same operation as the described step motor when is a DC motor.

When the focusing operation is completed, the operation moves to the shirt opening/closing operation shown in FIG. 3. That is, when the motor is rotated in the opposite direction after focusing, the partially toothed gear 5 meshes with the lever 10, rotates clockwise around the support shaft 10a against the spring lie, and the lever 11
7a - Since it is rotated counterclockwise around the support shaft lie, the shutter blade 12 is rotated in the direction of the arrow about the pin 13 due to the rotation of 1idO, and the shutter is opened. Although only one shutter blade 12 is shown here, as is well known, two shutter blades are actually used in combination. Here, if the shutter is configured as a program shutter, it closes before fully opening (for example, S.-8X-8, . in Fig. 5), and closes after fully opening (80-8
, -8,') and when it is closed after keeping it fully open (5
o-8, -8, -84'), etc.

FIG. 3 shows the aperture fully open. Closing the shutter is performed by reversing the motor.

With the subsequent large rotation of the motor in the clockwise direction, the gear 6 rotates significantly in the counterclockwise direction, the pin 6b comes into contact with the protrusion 7c of the ratchet pawl lever 7, and with the continued rotation, the ratchet pawl lever 7 is rotated around the spindle 7a. , the counterclockwise member disappears and the spring 9a
Return to initial position with force.

The switch SW3 in FIG. 4 is for obtaining an initialization signal.

"Effects of the Invention" As explained above, by implementing the configuration of the present invention, it is possible to focus the photographing lens, open/close the shutter, and drive the camera back to its initial position with a simple configuration.

[Brief explanation of drawings]

1 to 5 show embodiments of the present invention, FIG. 1 is a schematic diagram of the initial position structure, FIG. 2 is a schematic diagram for explaining the focusing drive, FIG. 3 is a diagram for explaining the shunter blade drive, and FIG. 4 is a diagram for explaining the initial position structure. FIG. 5 is a diagram showing a state of returning to the position, and FIG. 5 shows a time chart of the operation. l...Motor, 2-6...Gear, 78...
Ratchet claw lever 9... Ratchet gear, 1O
211... Lever 12... Shutter blade

Claims (1)

[Claims] In a photographing device that drives a photographic lens to a focusing position by a driving force of a motor and then drives a shutter to open and close, the motor and a driving force transmission mechanism repeatedly drive back and forth by a first specified rotation angle in a first direction. a drive transmission unit that reciprocates by a second specified rotation angle in a second direction after focusing to drive the shutter to open and close; and a drive transmission unit that drives the photographing lens to focus and connects it to the drive source via ratchet teeth on the circumference. The photographing lens drive ratchet gear is intermittently driven by a provided ratchet pawl and is biased in a direction opposite to the intermittent drive, and a shutter drive mechanism that drives the shutter blade to open and close by the drive source. Features a motor-driven focusing photographing device.