JPS6114025Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention is a shutter control device for a camera, in particular, by bringing the regulating part of a control member that operates at a slow speed by a delay mechanism having an inertia wheel into contact with a part of the delay mechanism. The present invention relates to a control device that terminates the operation of a control member and simultaneously terminates the operation of a delay mechanism.

For example, in some focal plane shutters, the opening operation of the leading blade is delayed by a certain number of seconds from the shutter release operation. The so-called exposure time is electrically controlled, and after the shutter release turns on the electronic trigger contact operating part for controlling the exposure time, the leading blade is released, and after the appropriate exposure time has elapsed. The electromagnet in the electronic circuit is demagnetized, allowing the trailing blade to close.

As described above, the control member is arranged to be operated by its own spring force in order to open the leading blade after a delay of a certain number of seconds. This control member is actuated by the restoring force of the spring member when the restraint is released, and the trigger contact actuating section is turned on immediately after the start of the actuation, and the leading blade is opened just before the actuation is stopped. Release the restraint on the vane drive arm. Furthermore, the actuation of this control element is effected slowly by means of a delay mechanism, for example consisting of a toothed wheel train with an inertial wheel.

However, the control member described above is formed with a tooth profile that meshes with the gear train of the delay mechanism, and when this control member operates, the inertia wheel rotates via the gear train, slowing down the operation of the control member. Make it familiar. The operation ends when the control member contacts the stopper, but even if the control member contacts the stopper and stops, the inertia wheel of the delay mechanism continues to rotate due to inertia, as its name suggests. shall be. Therefore, the force of the inertia wheel trying to rotate will be applied to the gear train, which will cause a large impact on the tooth profile when it stops, causing problems with the durability of the control member, and this impact will cause problems. The negative impact on the shutter mechanism is significant.

Also, in an attempt to improve this drawback to some extent, there is a method in which both the control member and the delay mechanism, especially the gear train, are brought into contact with the stopper and stopped at the same time. Unless they are done at exactly the same time, there is no effect, and it is extremely difficult to manufacture and assemble. Furthermore, as the operating force of the control member is increased, the rotational force of the inertia wheel also becomes stronger, so each stopper is required to be strong, and other stopper devices may also be required to ensure a reliable stop.

This invention was made in view of the above-mentioned drawbacks.
The present invention will be explained based on an embodiment shown in the figure below.

FIG. 1 shows the shutter set state, and FIG. 2 shows the state after the shutter operation is completed.

First, in the set state shown in FIG. 1, reference numeral 1 denotes a set gear, which forms a tooth profile 1b on the outer periphery and a charge arm 1c, and is rotatably supported by a shaft 1a. Reference numeral 2 denotes a control member, which has a toothed portion 2b, a toothed portion 2c on the outer periphery, and a hook portion 2d.
a, and a dextrorotary driving force is applied by a spring member (not shown), but this is suppressed by the contact of the hook portion 2d with a release lever 7, which will be described later. In the control member 2, the toothed portion 2b is similar to the toothed portion 1 of the set gear 1.
b, and the toothed portion 2c on the outer peripheral portion meshes with a gear portion 3b of an inertia wheel 3, which will be described later. The control member 2 also has an operating section for operating the opening member for starting exposure and an operating section for the trigger contact of the electronic circuit, but neither of these are shown. 3
is an inertia wheel, which forms a gear part 3b that meshes with the toothed part 2c of the control member 2, is rotatably supported by a shaft 3a, and a part of the outer periphery 3c corresponds to the movement locus of the planted pin 2e of the control member 2. It's invading inside. Reference numeral 4 designates an iron piece lever, which forms an arm portion 4e having arm portions 4b, 4c and an armature portion 4d, is rotatably supported by a shaft 4a, and is biased with a levorotatory driving force by a spring member 5. However, the arm portion 4b is connected to the pin 2e of the control member 2.
It is restrained by coming into contact with the Reference numeral 6 denotes a closing control electromagnet, which is fixed to the substrate. Reference numeral 7 denotes a release lever, which forms a locking part 7b and a release part 7c, is rotatably supported by a shaft 7a, and is biased with a left-handed driving force by a spring member 8. It is restrained by contact.

Next, the operation of the above configuration will be explained.

In FIG. 1, in conjunction with the depression of the shutter release button, a power switch of an electronic circuit (not shown) is turned on, and the release portion 7c of the release lever 7 is pushed, causing the lever 7 to rotate to the right.
The control member 2, which is released from restraint by the right rotation, rotates clockwise by its own spring force. The rotation becomes slow rotation by rotating the inertia wheel 3 of the delay mechanism. At the beginning of the slow rotation, a closing control electronic circuit (not shown) is triggered, and
The pin 2e gradually begins to release the push-up of the arm portion 4b of the iron piece lever 4. When the iron lever 4 is released, it becomes possible to turn the iron lever 4 to the left, but at this time, current is already flowing through the coil of the electromagnet 6 due to the power switch of the electronic circuit being turned on. It is attracted and cannot turn left and maintains the state shown in Figure 1. Further, the rotation of the control member 2 continues, and just before the rotation stops, the restraint of the leading blade drive arm (not shown) is released. By releasing the restraint, the leading blade opens the aperture and exposure begins. After that, the rotation pin 2e of the control member 2 comes into contact with the outer periphery 3c of the inertial wheel 3, and the rotation is completed and stopped (FIG. 2). At the same time, the rotation of the inertia wheel 3 is also braked and stopped by the friction between the pin 2e and the outer periphery 3c.

Thereafter, when the electronic circuit is reversed and the electromagnet 6 is de-energized after a proper exposure time has elapsed since the aforementioned opening of the leading blade, the iron piece lever 4 is rotated to the left by the spring 5, and the arm portion 4c is moved backward (not shown). Release the restraint on the vane drive arm (Figure 2). When the restraint is released, the trailing blades operate to close the aperture and the exposure ends.

After photographing is completed, in order to set the shutter again, the control member 2 rotates in conjunction with the rotation of the control member 2, and the set lever 1, which is in the state shown in FIG. 2, is rotated to the right. This rotation to the right causes the control member 2 to rotate to the left against the tension of the spring, and is set to the state shown in FIG. On the other hand, when the control member 2 is rotated to the left, the pin 2e pushes the arm portion 4b of the iron piece lever 4, causing it to rotate to the right and similarly return to the state shown in FIG. At this time, the armature 4d is in contact with the electromagnet 6.

In the above embodiment, the pin 2e of the control member 2 was brought into contact with the outer periphery of the inertial wheel 3.
However, the present invention is not limited to this, and it is also possible to contact a part of the gear train of the delay mechanism.

Furthermore, when the control member 2 is operated by a stronger spring member, the rotational force of the inertia wheel becomes correspondingly larger, but the force with which the pin 2e pushes the inertia wheel 3 also becomes stronger, so another brake member is provided. There's no need. On the contrary, when the control member 2 is operated by a weak spring member, the force of the pin 2e pushing the inertial wheel 3 becomes weak, but at this time there is no problem because the rotational force of the inertial wheel 3 is also weakened.

The present invention has the above-mentioned configuration, and since the brake is applied to the delay mechanism at the same time, it has the effect of reducing the shock and bouncing of the control member when it stops.

[Brief explanation of the drawing]

FIG. 1 is a plan view of an embodiment of the present invention, and FIG. 2 is an explanatory diagram of the operation of FIG. 1. 2...Control member, 2e...Restriction pin, 3...Inertia wheel.

Claims (1)

[Scope of utility model registration request] It consists of a control member that starts operating when the shutter release is operated, and a delay mechanism consisting of a gear train having an inertia wheel to slow down the operation of the control member. A shutter control device for a camera, characterized in that a regulating part is provided that comes into contact with a part of the delay mechanism, and the operation of the control member is terminated when the regulating part comes into contact with a part of the delay mechanism. .