JP2017026834A - Amount of light adjustment device and optical apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve durability of a light shielding blade without deteriorating acceleration of shutter speed.SOLUTION: An amount of light adjustment device includes: one or more sheets of an amount of light adjustment member whose driving source is a rotatable rotor magnet and that can advance or retreat relative to a light passage opening while rotating in response to rotation of the rotor magnet; a transmission member for transmitting rotation of the rotor magnet to the amount of light adjustment member; and an apparatus base for supporting a driving unit. An angle defined by the rotation direction of a drive pin provided with the transmission member and the operation direction of a cum provided with the amount of light adjustment member significantly changes and rotation speed of the amount of light adjustment member is changed by the rotational position of the rotor magnet.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a light amount adjusting device mounted on an optical apparatus such as a still camera, a video camera, or an interchangeable lens.

  In recent years, shutter devices and the like have been known as light amount adjustment devices. For example, products such as digital still cameras and digital video cameras that require shutter devices are required to have high image quality, and shutter devices operate at high speed. Is requested.

JP 2002-287207 A

  However, for example, durability becomes a problem with high-speed operation of the light amount adjusting member such as the light shielding blade and the filter blade.

  The present invention provides a light amount adjusting device and an optical apparatus with improved durability.

The light amount adjusting device of the present invention includes an opening forming member that forms an opening through which light passes, a light amount adjusting member that enters and exits the opening, a power transmission member that transmits power to the light amount adjusting member, and the power transmission A rotation member that rotates the member, and the power transmission member and the rotation member are connected with the rotation direction of the rotation member and the rotation direction of the power transmission member as opposite directions.
According to such an aspect of the present invention, by performing power transmission in which the rotation directions of the rotating member and the power transmission member are opposite to each other, the structure in which the moving speed of the light quantity adjusting member can be easily adjusted is achieved. In the drive mode of the light quantity adjustment member accompanied by the operation stop, it is possible to reduce the reaction caused by the drive stop of the light quantity adjustment member and improve the durability of the light quantity adjustment member.

In the present invention, the angle formed by the rotation direction of the drive pin provided in the power transmission member and the direction of the cam hole provided in the light amount adjustment member changes as the power transmission member rotates. This may be a feature.
According to this aspect of the present invention, by changing the engagement state between the drive pin and the cam hole, for example, the speed adjustment of the light amount adjusting member can be performed by the rotational position of the power transmission member, and the light amount adjusting member is stopped. The movement speed of the light quantity adjusting member can be controlled to be decelerated before, and the reaction (bound action or the like) during the stop operation of the light quantity adjusting member can be reduced.

  The light amount adjusting device of the present invention is not limited to the above. For example, a rotating rotor magnet is used as a driving source, and the light amount adjusting device can move forward and backward with respect to the light passage opening while rotating according to the rotation of the rotor magnet. In a light amount adjusting device having at least one light amount adjusting member, a transmission member that transmits the rotation of the rotor magnet to the light amount adjusting member, and a device substrate that supports the drive unit, the rotation direction of the drive pin provided on the transmission member The angle between the operating direction of the cam provided on the light amount adjusting member changes greatly, and the rotation speed of the light amount adjusting member may vary depending on the rotational position of the rotor magnet. In this case, the rotational angular velocity when colliding with the stopper is lower than the rotational angular velocity when shielding the aperture diameter, and the impact force colliding with the stopper may be reduced.

  ADVANTAGE OF THE INVENTION According to this invention, the light quantity adjustment apparatus and optical instrument which can improve durability are realizable.

The disassembled perspective view which shows the principal part of the light quantity adjustment apparatus which concerns on one Embodiment of this invention. The figure which shows the open state of the light-shielding blade of FIG. The figure which shows the fully closed state of the light-shielding blade | wing of FIG. The figure which shows the open state of the drive part of FIG. The figure which shows the fully closed state of the drive part of FIG. The figure which shows the fitting state of the blade | wing and drive pin in an open state The figure which shows the fitting state of the blade | wing and drive pin in the middle of operation | movement The figure which shows the fitting state of the blade | wing and drive pin in a fully closed state

Example 1
Hereinafter, the present invention will be described in detail based on illustrated embodiments.

  1 to 8 are diagrams relating to a light amount adjusting device according to an embodiment of the present invention. FIG. 1 is an exploded perspective view of a shutter device, FIG. 2 is a diagram showing an open state of a light shielding blade, and FIG. FIG. 4 is a perspective view showing the drive unit in the fully open state of the blade, FIG. 5 is a perspective view showing the drive unit in the fully closed state of the shutter, and FIG. 6 is a view showing the drive unit in the fully open state. FIG. 7 is a diagram showing a fitting state of the pin, FIG. 7 is a diagram showing a fitting state of the blade and the driving pin during operation, and FIG. 8 is a diagram showing a fitting state of the blade and the driving pin in the fully closed state.

  In these drawings, reference numeral 1 denotes a base plate (device base), which includes an opening 1a, blade rotation shafts 1b and 1c, a drive gear rotation shaft 1d, and stopper portions 1e and 1f. The ground plane 1 is an example of an opening forming member that forms the opening 1a. The stopper portions 1e and 1f have a structure that stops the rotation operation of the light shielding blades 8 and 9 that will be described later, and the stress concentrates on the abutting portions 8c, 8d, 9c, and 9d of the light shielding blades 8 and 9 and deteriorates.・ The contact part is long enough not to damage it.

  Reference numeral 2 denotes a rotor magnet that is a rotating member, and its outer peripheral surface is magnetized to two poles (N pole and S pole). Reference numeral 3 denotes a drive gear, which is configured integrally with the magnet 2. Examples of the integration method include fixing by an adhesive and, if a resin, insert injection molding. The integrally configured magnet 2 and drive gear 3 are supported by a drive gear rotating shaft 1d provided on the main plate 1 and can rotate.

  Reference numeral 4 denotes a stator yoke made of a soft magnetic material. The stator yoke 4 is disposed on the outer peripheral curved surface of the magnet 2.

  Reference numeral 5 denotes an electromagnetic coil unit, which is configured by winding a coil made of a conductive wire around a bobbin. The electromagnetic coil unit 5 is attached to the ground plane 1 with the stator yoke 4 inserted.

  Reference numeral 6 denotes an actuator cover, which is attached to the main plate 1 and holds a stator yoke 4, a drive gear 3, and a slave gear 7 serving as a power transmission member.

  7 is a slave gear and includes a drive pin 7a that fits with a light shielding blade described later. It is connected to the gear portion 3a of the drive gear by a gear and rotates as the drive gear 3 rotates. The gear ratio is set so that the rotation amount of the slave gear 7 is larger than the rotation amount of the rotor magnet 2. That is, the rotor magnet 2 and the driven gear 2 rotate in the reverse direction, that is, the driven gear 2 rotates in the reverse direction as the rotor magnet 2 rotates.

  As shown in the drawing, the magnet 2, drive gear 3, stator yoke 4, electromagnetic coil unit 5, actuator cover 6 and subordinate gear 7 are assembled to constitute an electromagnetic actuator serving as a drive source for the shutter device. This electromagnetic actuator drives light shielding blades 8 and 9 which will be described later.

  Reference numerals 8 and 9 denote light-shielding blades that rotate by the electromagnetic actuator to open and close the shutter device.

  Here, the structure of the light shielding blades 8 and 9 will be described in detail with reference to FIGS. The shading blade 8 has a rotation shaft hole 8a and a hole 8b. The rotation shaft hole 8a is fitted to the blade rotation shaft 1c of the main plate, and the hole 8b is fitted to the drive pin 7a. In the present embodiment, the rotary shaft hole 8a has a round hole shape, and the hole portion 8b has a long hole shape.

  The shading blade 9 has a rotation shaft hole 9a and a hole 9b. The rotation shaft hole 9a is fitted to a blade rotation shaft 1b provided on the main plate 1, and the hole 9b is fitted to the drive pin 7a. As for the light shielding blade 9, similarly to the light shielding blade 8, the rotation shaft hole 9 a has a round hole shape, and the hole portion 9 b has a long hole shape.

  The light shielding blades 8 and 9 can be manufactured using a plate-like plastic. For example, there is a method in which a general PET resin plate of about 30 to 100 μm is coated with a carbon-based sliding paint on the surface. This plate material can be formed by punching and can be manufactured without increasing the cost from the prior art.

  In the shutter device having the above configuration, when the electromagnetic coil unit 5 is energized, the rotor magnet 2 and the drive gear 3 are rotated in accordance with the energizing direction by the magnetic action with the stator yoke 4, and the subordinate gear 7 connected by the gears is also rotated. To do. Accordingly, the drive pin 7a inserted through the holes 8b and 9b of the light shielding blades 8 and 9 rotates, so that the light shielding blades 8 and 9 are centered on the respective rotation shaft holes 8a and 9a in the rotation direction. 2 rotates from the open state of FIG. 2 to the fully closed state of FIG. On the other hand, when the electromagnetic coil unit 5 is reversely energized, the magnet 2 rotates in the reverse direction and the drive pin 7a also rotates in the reverse direction, so that the light shielding blades 8 and 9 are opened from the fully closed state in FIG. Rotate to state.

  Here, the fitting part of the hole 8b provided in the light shielding blade 8 and the drive pin 7a will be described in detail with reference to FIGS. As described above, the rotation amount of the drive pin 7a provided in the slave gear is set to be larger than that of the structure that rotates integrally with the rotor magnet.

  In this embodiment, when the closing operation starts from the open state of FIG. 6, the hole shape 8b is determined so that the direction of the hole 8b and the operation locus 7b of the drive pin 7a coincide. At this time, the light shielding blade 8 is retracted from the opening 1a of the main plate.

  When the closing operation proceeds from the open state of FIG. 6, the arrangement shown in FIG. 7 is obtained, and the direction of the hole 8b and the operation locus 7b of the drive pin are orthogonal to each other. At this time, the light-shielding blade 8 is in the middle of entering the opening 1a of the main plate.

  When the closing operation further proceeds from the state shown in FIG. 7, the angle formed by the direction of the hole 8b and the operation locus 7b of the drive pin is substantially reduced. In the fully closed state shown in FIG. The slave gear 3 and the light-shielding blade 8 are arranged so that the pin movement trajectories 7b coincide. When the angle formed by the direction of the hole 8b and the driving locus 7b of the drive pin becomes small, the amount of rotation of the light shielding blade 8 that rotates about the blade rotation shaft hole 8a becomes small, and the direction of the hole 8b and the operation of the drive pin When the locus 7b coincides, the light shielding blade 8 does not rotate.

  As described above, when the magnet 2 and the drive pin 7a move at the same angular acceleration when operating from the open state of FIG. 6 to the fully closed state of FIG. 8, the light shielding blade 8 shields the opening from light shielding. The angular velocity becomes the fastest, and immediately before the closed state, the angular velocity becomes slow. That is, the rotation operation is decelerated, and comes into contact with the main plate stopper 1e provided on the main plate and stops. Further, since the rotational speed of the blades increases while the opening is shielded, the shutter speed can be improved.

  When operating from the fully closed state of FIG. 8 to the open state of FIG. 6, the angular velocity of the light shielding blade 8 is reduced immediately before the open state. That is, the rotational operation is decelerated, and comes into contact with the main plate stopper 1f provided on the main plate and stops.

  The light shielding blade 9 is decelerated and stopped similarly to the light shielding blade 9 in a state close to the closing end or the opening end although the angle formed by the operation direction of the hole 8b and the drive pin 7a is larger than that of the light shielding blade 8. To do.

  By the way, when the light shielding blades 8 and 9 are rotated from the open state to the fully closed state, as shown in FIG. 3, the abutting portion 8c abuts against the stopper portion 1c of the base plate 1, and the light shielding blade 9 As shown in FIG. 3, the abutting portion 9 c abuts against the stopper portion 1 ed of the main plate 1. On the other hand, when the light shielding blades 8 and 9 are rotated from the fully closed state to the open state, the light shielding blade 7 has its abutting portion 8d abutted against the stopper portion 1d of the base plate 1 as shown in FIG. As shown in FIG. 2, the abutting portion 9 d abuts against the stopper portion 1 c of the main plate 1.

  In the conventional shutter device, when the above opening / closing operation is repeated, the abutting portions 7c, 8c, 7d and 8d of the light shielding blades 8 and 9 with the base plate 1 and the hole portion 7b which is a fitting portion with the driving pin 7a. , 8b. However, in the present embodiment, as described above, since the rotation speed of the light shielding blades 7 and 8 when colliding with the stopper portions 1c and 1d of the main plate is slowed, the impact received by the abutting portions 7c, 8c, 7d and 8d The force is small and it is difficult for deterioration and damage to occur. Thereby, the durability of the shutter device can be improved.

  In the present embodiment, as described above, since the deterioration and damage are suppressed without increasing the thickness of the light shielding blades 8 and 9 as in the conventional case, the weight of the light shielding blades 8 and 9 is increased more than necessary. Therefore, the reduction in shutter speed can be minimized. That is, the increase in shutter speed is not impaired.

  Although the light quantity adjusting blades in this embodiment are two light shielding blades, they may be one light shielding blade or three or more light shielding blades. Moreover, it may be a small aperture blade that switches the size of the aperture diameter, or a dimming filter blade.

  If the light quantity adjustment device of this embodiment is installed in an optical device such as a camera, the exposure time shift caused by damage to the light-shielding blade can be suppressed, so that the brightness of the image quality shifts even when the number of photographs taken increases. It becomes difficult to do.

DESCRIPTION OF SYMBOLS 1 Ground plane 1a Opening part 1b, 1c Blade | shaft rotation shaft 1d Drive gear rotation shaft 1e, 1f Stopper part 2 Magnet 3 Drive gear 3a Gear part 4 Stator yoke 5 Electromagnetic coil unit 6 Actuator cover 7 Subordinate gear 7a Drive pin 7b Motion locus 8 Light shielding Blade 8a Rotating shaft hole 8b Hole portion 8c Butting portion 8d Butting portion 9 Light shielding blade 9a Rotating shaft hole 9b Hole portion 9c Butting portion 9d Butting portion

Claims (3)

An opening forming member that forms an opening through which light passes;
A light amount adjusting member entering and exiting the opening;
A power transmission member that transmits power to the light amount adjustment member;
A rotating member that rotationally drives the power transmission member,
The light quantity adjusting device, wherein the power transmission member and the rotation member are connected with the rotation direction of the rotation member and the rotation direction of the power transmission member as opposite directions.   The angle formed by the direction of rotation of a drive pin provided in the power transmission member and the direction of a cam hole provided in the light quantity adjustment member changes as the power transmission member rotates. The light quantity adjusting device according to 1.   An optical apparatus comprising the light amount adjusting device according to claim 1.

Images