JPH01938A - camera - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a camera, and in particular, to a camera configured such that movement of the lens barrel and operation of an exposure device are performed by a common motion generating member made of, for example, a shape memory alloy. It's about cameras.

[Background of the Invention] Recently, cameras that use a shape memory alloy member as a drive source instead of a motor have been proposed. Since the drive source is separate, the structure is simpler than cameras using motors, but the cost reduction advantage is not necessarily great.

[Object of the Invention] An object of the invention is to provide a camera having a structure in which a drive source for lens barrel movement and a drive source for exposure operation are made common, and a member made of a shape memory alloy is used as the drive source. The purpose of the present invention is to provide a camera that has a greater cost reduction advantage than cameras that have already been proposed.

[Summary of the Invention] In the camera according to the present invention, a lens barrel equipped with an exposure device and capable of moving back and forth is provided with a rotating member capable of rotating about a vertical axis, and two lenses fixed at both ends of the rotating member are provided. When the parallel motion generating members made of shape memory alloy are operated at the same time, the lens barrel is moved, and when only one of the movable members is operated, the rotating member is rotated to move the exposure device. It is characterized in that it is configured to operate.

In other words, in the camera of the present invention, the drive means for moving the lens barrel and the drive means for operating the exposure device are made of the same shape memory alloy member, so it is more effective than conventional cameras of the same type. Since the amount of shape memory alloy used is reduced and the camera structure is simplified, the cost can be further reduced compared to the previously proposed cameras.

[Embodiments of the Invention] Examples of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing structural parts related to the present invention in a first embodiment of the camera of the present invention.

In FIG. 1, la and 1b are bearings protruding from the camera body (not shown), and 2 is equipped with an exposure device such as a shutter and an aperture mechanism, as well as a photographing lens 3 and a light receiving window 4 for distance measurement. A lens barrel 5 has both ends fixed to the bearings 1a and 1b and is arranged parallel to the optical axis of the photographing lens 3. A lens barrel guide shaft 2a projects from the top surface of the lens barrel 2 and is connected to the lens barrel. A protrusion having a shaft hole that is loosely fitted into the guide shaft 5; 6 a spring fitted onto the shaft 5 and always biasing the protrusion 2a toward the front of the camera; 7 a lower surface of the lens barrel 2; 8 is a lens barrel movement amount detector such as a photointerrupter that is fixed to the camera body or the like and detects the amount of movement of the slit plate 7 without contact; 9 is a lens barrel movement amount detector fixed to the rear end of the lens barrel 2; 10 is an exposure device operating lever that engages with a cam surface 9b formed at one end of the rotating member 9 and can be rotated in the direction of arrow a in the figure; A first motion generating member 12 made of a shape memory alloy is fixed to one end of the rotating member 9 and the camera body IC and extends parallel to the lens barrel guide shaft 5; A second motion generating member 13 made of a shape memory alloy, which is fixed to the main body portion 1d and extends parallel to the first motion generating member 11, is connected to the first motion generating member 13 via a rotating member 9.
'HL and a power distribution line electrically connected to one end of each of the second motion generating members 11 and 12;
A power distribution line 15 is connected to the other end of the first motion generating member 11 fixed to the camera body 1d, and 15 is a power distribution line connected to the other end of the second motion generating member 12 fixed to the camera body 1d. .

The power distribution lines 13 to 15 are connected to three connection terminals of a control circuit 16 shown in FIG. Two of the three connection terminals are selected in accordance with the current, and current is applied to the distribution line.

When taking pictures with a camera having the configuration shown in FIGS. 1 and 2, when the release button (not shown) is pressed, the control circuit 16 is energized, and the photometer and range finder (not shown) Photometry and distance measurement are performed. When the photometry result and the distance measurement result are stored, the control circuit 16 first energizes terminals A and C to move the lens barrel 2 to the focusing position corresponding to the distance measurement result, and connects the power distribution line. The first and second motion generating members 11 and 12 are electrically heated via 14 and 15 . Therefore, the first and second motion generating members 11 and 12
, and the members 11 and 12 contract by an equal amount in the direction indicated by the arrow in FIG. 3, so that the rotary member 9 moves backward parallel to the optical axis while maintaining the posture shown in FIG.

Therefore, the lens barrel 2 integrated with the rotating member 9 also moves backward along the optical axis while compressing the spring 6.

In this case, the amount of movement of the lens barrel 2 is detected by the lens barrel displacement amount detector 8, and the detection result is fed back to the control circuit 16 and compared with a predetermined focusing movement amount. Then, when the amount of movement of the lens barrel 2 reaches a predetermined focusing movement amount, the lens barrel 2 is restrained by a lens barrel stopping device (not shown), and the lens barrel 2 is stopped at the in-focus position.

When the stoppage of the lens barrel 2 is confirmed by the output signal of the detector 8, the control circuit 16 cuts off the power to the connection terminals A and C, and instead turns off the power to the connection terminals A and B. Therefore, the power supply to the motion generating member 12 is cut off and the movement generating member 12
returns to the extended state, but the other motion generating member 11 is maintained in the contracted state, so the rotating member 9 is rotated clockwise about the shaft 9a as shown in FIG. the result,
Slanted cam surface 9b formed at one end of rotating member 9
In FIG. 1, the exposure operating lever 10 is rotated downward, so that the exposure device inside the lens barrel 2 is operated by the lever 10, and exposure is performed. After the exposure is completed, the control circuit 16 cuts off the power to the connection terminals A and B, so that the second motion generating member 11 returns to its extended state, and the rotating member 9 also returns to its original state perpendicular to the optical axis. . And the exposure control lever 10
is rotated clockwise in FIG. 1 by the force of a spring (not shown), and the tip of the lever 10 returns to the initial position in FIG. 1 while being in pressure contact with the cam surface 9b of the rotating member 9.

When the first and second motion generating members 11 and 12 reach the initial extended state and the lens barrel 2 is released from being restrained by the lens barrel stop device, the lens barrel 2 moves forward due to the elastic force of the spring 6. It is pushed back and returns to its initial position.

FIG. 5 shows the main structure of a camera according to a second embodiment of the present invention, and in this figure, members indicated by the same reference numerals as in FIG. 1 are the same as those in FIG. 1.

The embodiment shown in FIG. 5 differs from the embodiment shown in FIG. The elongated body is wound around at least one pulley, and both ends of the elongated body are fixed to both ends of the rotating member.

In FIG. 5, pulleys 17 and 18 are rotatably installed on a stationary part of the camera body, etc., and 19 has both ends fixed to both ends of the rotating member 9 and is hooked onto the pulleys 17 and 18. A motion generating member made of a long body made of a shape memory alloy; 20 is a sliding contact terminal that slides into contact with the motion generating member 19 at a position between the pulleys 17 and 18;
1 is a power distribution line connected to the motion generating member 19 at the right end of the rotating member 9; 22 is a power distribution line connected to the sliding contact terminal 20;
Reference numeral 23 denotes a power distribution line connected to the motion generating member 19 at the left end of the rotating member 9.

FIG. 6 shows connection terminal A- to which the distribution lines 21 to 23 are connected.
A control circuit 16 with C is shown.

Next, a case where photographing is performed using a camera having the configuration shown in FIGS. 5 and 6 will be described.

When a release button (not shown) is pressed, the control circuit 16 is activated, and photometry and distance measurement are performed by a photometer and a distance measurement device (not shown).

When the photometry result and the distance measurement result are stored, the control circuit 16 first energizes terminals A and C to move the lens barrel 2 to the focusing position corresponding to the distance measurement result, and connects the power distribution line. 2
1 and 23, the entire motion generating member 19 is energized from both ends thereof. Therefore, since the member 19 contracts uniformly over its entire length, the rotating member 9 is pulled in the direction shown by arrow C in FIG.
moves backward parallel to the optical axis while compressing the spring 6.

In this case, the amount of movement of the lens barrel 2 is detected by the lens barrel movement amount detector 8, and the detection result is fed back to the control circuit 16 and compared with a predetermined amount of focusing movement. Then, when the amount of movement of the lens barrel 2 reaches a predetermined focusing movement amount, the lens barrel 2 is restrained by a lens barrel stopping device (not shown), and the lens barrel 2 is stopped at the in-focus position.

When the stoppage of the lens barrel 2 is confirmed by the output signal of the detector 8, the control circuit 16 cuts off the power to the connection terminals A and C and energizes the connection terminals A and B instead. Therefore, the portion 1 between the left end of the rotating member 9 and the sliding contact terminal 20
9a (that is, the left half of the member 19) is cut off, and the portion 19a returns to the extended state, but the other half 19b of the motion generating member 19 is maintained in the contracted state, so that rotation is not possible. The moving member 9 is rotated clockwise about the shaft 9a as shown in FIG. As a result, the inclined cam surface 9b formed at one end of the rotating member 9 rotates the exposure operating lever 10 downward in FIG. 5, so that the exposure device inside the lens barrel 2 is operated by the lever 10. Exposure is performed. After the exposure, the control circuit 16 cuts off the power to the connection terminals A and B, so that the entire movement generating member 19 returns to its extended state, and the rotating member 9 also returns to its original state perpendicular to the optical axis. Return. Then, the exposure operation lever 10 is rotated clockwise in FIG. 1 by the force of a spring (not shown).
The tip of 0 returns to the initial position shown in FIG. 1 while being in pressure contact with the cam surface 9b of the rotating member 9.

Further, when the entire motion generating member 19 reaches the initial extended state and the lens barrel 2 is released from being restrained by the lens barrel stop device, the lens barrel 2 is pushed back forward by the elastic force of the spring 6. Return to initial position.

[Effects of the Invention] As explained above, in the camera according to the present invention, since the drive source for moving the lens barrel and the drive source for operating the exposure device are configured by a common motion generating member, the camera is more efficient than conventional cameras of the same type. The advantage is that it can be manufactured at low cost.

Note that the motion generating member used as the drive source is not limited to a shape memory alloy, and may be any member that can generate a predetermined power.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the main structure of a first embodiment of a camera according to the present invention, FIG. 2 is a diagram showing an electrical configuration related to the structure of FIG. 1, and FIGS. 3 and 4. 1 is a diagram showing the operation of the main parts of the camera of FIG. 1, FIG. 5 is a diagram showing the structure of the main parts of the second embodiment of the camera of the present invention, and FIG. 6 is related to the structure of FIG. 5. Figures 7 and 8 showing the electrical configuration
This figure is a diagram showing the operation of the main parts of the camera of FIG. 5. 1a and 1b...bearing portion 2...lens barrel 3...taking lens 4...
Light receiving window for distance measurement 5... Lens barrel guide shaft 6... Spring
7... Slit plate 8... Lens barrel movement amount detector 9... Rotating member 10... Exposure operation lever 1
1 and 12...Motion generating member 13-15...Distribution line 16...Control circuit 17 and 18...Pulley 19...Motion generating member 21-23...Distribution line 20
...Sliding terminal. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6

Claims (3)

[Claims] (1) In a camera equipped with a lens barrel that is equipped with an exposure device such as a shutter and an aperture mechanism and is movable back and forth along the optical axis of the photographic lens, the mirror is rotatable about a vertical axis. a rotating member whose central portion is pivotally attached to the cylinder; an exposure operating lever that is driven by the rotating member to operate the exposure device when the rotating member is rotated in a specific direction; a driving means for moving the lens barrel forward straightly along the optical axis via a member and rotating the rotating member; a movement for causing the driving means to move the lens barrel straightly; and the rotation. and a control means for generating a movement for causing the member to perform a rotational motion, and is configured such that the driving means moves the lens barrel and performs an exposure operation of the exposure device. A camera characterized by: (2) In a camera equipped with a lens barrel that is equipped with an exposure device such as a shutter and an aperture mechanism and is movable back and forth along the optical axis of the photographic lens, the mirror is rotatable about a vertical axis. a rotating member whose center portion is pivotally attached to the cylinder; an exposure operating lever which is driven by the rotating member to operate the exposure device when the rotating member is rotated in a specific direction; A first elastic movement generating member made of a shape memory alloy, which is connected to one end of the rotating member and whose other end is connected to a stationary member and extends parallel to the optical axis; a second elastic movement generating member made of a shape memory alloy, the second elastic movement generating member being connected to one end and the other end being connected to a stationary member and extending parallel to the first elastic movement generating member; 1. A camera comprising a control means for controlling the order and timing of energization of the expansion and contraction movement generating members. (3) In claim 1, the driving means:
at least one pulley disposed on a stationary member at a position rearward of the rotating member, one end of which is coupled to one end of the rotating member, and the other end coupled to the other end of the rotating member; a long body made of a shape memory alloy wound around the pulley;
A camera characterized in that the control means includes electric means for energizing one half of the elongated body.