JP4447293B2 - Shutter device and optical apparatus including the same - Google Patents

Description

  The present invention relates to a shutter device for optical equipment. More specifically, the present invention relates to a shutter device that can be suitably used for an optical apparatus such as a digital camera or a video camera.

  In recent years, shutter devices incorporated in digital cameras and the like have been reduced in size and increased in shutter speed. A technique related to this is disclosed in Patent Document 1, for example. The shutter device disclosed in Patent Document 1 includes two shutter blades that open and close an opening for exposure by swinging. Each of the shutter blades has a connection hole, and a drive pin that is reciprocated through the connection hole is inserted. The shutter blade is configured to open and close the opening as the drive pin moves. The connecting hole is formed with a closed inner edge portion that engages with the drive pin during the closing operation and an open inner edge portion with which the drive pin engages during the opening operation. A retreat inner edge that retreats in the direction opposite to the closing direction is formed on the close side inner edge.

  The shutter opening can be closed at a high speed by providing the retreat inner edge as described above. Further, a play allowance W in which the drive pin is allowed to move is formed between the closed inner edge and the open inner edge. By providing the allowance W in this way, the load at the beginning of the movement of the drive pin is reduced, and the shutter blade is closed after the drive pin is sufficiently accelerated to increase the shutter speed. .

  Patent Document 2 also discloses a shutter device that reduces the load when the drive pin is activated. In the shutter disclosed in Patent Document 2, the sector also has a through hole (corresponding to the connecting hole in Patent Document 1), and a drive pin is passed through the through hole. This through-hole is set large enough to be driven substantially without load immediately after the drive pin is activated. This shutter device also drives the sector after the drive pins have sufficiently accelerated to increase the shutter speed.

JP 2002-162666 A JP 2002-277927 A

  In the shutter device disclosed in the above-described prior art, shutter blades having the same shape are arranged symmetrically, and a drive pin is inserted into a connecting hole (through hole) formed in the shutter blade to reciprocate the shutter opening. It is the structure of opening and closing. That is, the left and right shutter blades open the shutter opening when the drive pin is driven in the opening direction, and the shutter blade closes the shutter opening when the drive pin is driven in the opposite closing direction.

  However, in recent years, there has been a demand for a shutter device with higher function that can form different aperture states such as a small aperture even if it is small. In the conventional shutter device described above, since the drive pin that has been speeded up collides with a wide through hole formed in the shutter blade, the shutter blade can be closed at high speed. However, it does not have a function to change the aperture state. In order to add a diaphragm function to such a shutter device, a structure in which diaphragm blades are separately arranged and driven is required. In this case, the structure becomes large and complicated, which is against the demand for miniaturization.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-described conventional problems and provide a shutter device that can drive a sector at high speed and can easily form an aperture state.

The object includes a swingable sector for opening and closing the shutter opening, an operating member for driving the sector , and an actuator for driving the operating member on a substrate having a shutter opening. Comprises a through hole with which the actuating member engages, the through hole being formed continuously with the acceleration region for moving the actuating member with no load, and the sector as the actuating member moves. Can be achieved by a shutter device including a swing region having a cam groove formed so as to move along a predetermined locus.

  According to the present invention, it is possible to form a state in which the operating member is accelerated in the acceleration region and then enters the swing region. Since the cam groove is formed in the swing region, the sector can be swung to a desired position at a high speed as the operating member moves. Therefore, a shutter device that moves the sector to a desired position at high speed can be provided.

  The actuating member may be a drive pin that is fixed to the rotor shaft of the actuator and moves along an arcuate locus, and the acceleration region may have a shutter structure formed in an arc shape corresponding to the locus of the drive pin. The starting position of the operating member is set at the end of the acceleration region so that the operating member is accelerated in the acceleration region, and the swing region swings the sector to fully close the shutter opening. If the fully closed cam groove is included, a shutter device that closes the shutter opening at high speed can be obtained.

  Further, the sector may include a shutter blade and a small aperture blade, and the swing region may further include a small aperture cam groove that positions the small aperture blade in the shutter opening continuously to the fully closed cam groove. Good. If comprised in this way, it will become a shutter apparatus which can also form a small aperture state.

  Also, it includes a plurality of sectors, and the operating member is engaged with the through holes of these sectors, and a fully open state, a fully closed state, and a small aperture state are formed while the operating member is moved in one direction. When the fully open state is changed to the fully closed state, the operating member enters the swing region from the acceleration region, and the through hole is formed so as to close the shutter opening at a high speed in the sector. A shutter device can also be formed. Further, a widened region for reducing a load on the operating member toward the acceleration region may be formed between the swing region and the acceleration region. When such a structure is employed, the operating member can be driven smoothly.

  When the sector has a structure in which a hole is formed in a region that does not reach the shutter opening when the sector moves to a position where the shutter opening is closed, the sector movement can be further speeded up.

  With the shutter device having the above-described configuration, the sector can be moved at a high speed and can be moved to a desired position. Therefore, if an optical device such as a digital camera including the shutter device is used, a clear captured image can be obtained. Can do.

  As described above, according to the present invention, it is possible to provide a shutter device that can drive a sector at high speed and can swing the sector along a desired locus.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Before showing a specific embodiment of the present invention, a basic concept employed in the present invention will be described with reference to FIG. 1 in order to facilitate understanding of the present invention. FIG. 1 is a diagram showing a case where one sector is driven using a cam mechanism. FIG. 1A schematically shows a configuration for driving the sector 100 at a high speed. FIG. 1B is a schematic diagram of a sector that has been improved to smoothly swing the sector 100 shown in FIG.

  The sector 100 shown in FIG. 1A is pivotally supported by a fixed shaft (support shaft) 101 of a substrate (not shown) and is swingable. The sector 100 has a through hole 110 into which an operating member 115 that moves along a predetermined locus (for example, an arc) is engaged. When the actuating member 115 moves in the clockwise direction CW, the sector 100 is also configured to swing in the clockwise direction. The through hole 110 of the sector 100 is formed in a special shape. An acceleration region 111 is formed in the front portion of the through hole 110. This acceleration region is formed in a shape along the locus of the operating member 115. In this acceleration region, the operating member 115 can move in an unloaded state. Therefore, the operating member 115 can be accelerated before the sector 100 is swung by moving the operating member 115 with the end 111-S of the acceleration region as the starting position.

  In the through hole 110, a swing region 112 is formed continuously with the acceleration region 111. The swing region 112 is formed with a cam groove that swings the sector 100 along a predetermined locus when the operating member 115 moves in this region. In FIG. 1A, the swing region 112 is shown in a simplified manner. By forming the swing region 112 with a cam groove in which a straight line, a curve, an arc, or the like is combined, the sector 100 can be swung along a desired locus.

  For example, as shown in FIG. 1A, the sector 100 causes the shutter member aperture to fully open when the operating member 115 is present at the end 111-S of the acceleration region 111. A cam groove (cam curve) that guides the sector 100 to a predetermined position is set in the swing region 112. If comprised in this way, since the operating member 115 fully accelerated in the acceleration area | region 111 will enter into the rocking | swiveling area | region 112, the sector 100 can be moved to a predetermined position at high speed. If this desired position is set to the fully closed position of the shutter opening, a structure for closing the shutter at high speed can be realized.

  In the configuration shown in FIG. 1A, the operating member 115 accelerated in the acceleration region 111 is guided to the swing region 112, so that the sector 100 can be guided to a desired position at a high speed after the swing is started. As described above, the configuration shown in FIG. 1A is not a simple structure in which the drive pin collides at a high speed with a wide through-hole formed in the sector as in the prior art to close the sector. In this configuration, the speed-up operating member 115 is guided to the swing region 112 and the sector 100 is moved to a predetermined position along the cam groove. Therefore, the structure of the present sector 100 can be widely applied to a case where the sector is to be moved to a predetermined position at a high speed other than the form in which the shutter opening is closed at a high speed.

  Further, by continuously forming cam grooves having different shapes in the swing region 112, the sector 100 can be continuously guided to an arbitrary position. For example, a cam groove that guides the sector 100 to the position where the shutter opening is closed in the swinging region 112, and the sector 100 is guided to a position near the shutter opening to assist other sectors while the other sector closes the shutter opening. And a cam groove. With this configuration, one sector can be configured to play a plurality of roles.

  FIG. 1A shows an example in which one sector 100 is driven, but a plurality of sectors are driven by the actuating member 115, and the shape of the through hole provided in each sector is appropriately changed to fully open. A plurality of states such as fully closed and aperture can be formed. Further, a small aperture state can be formed by employing small aperture blades in the sector.

  Note that FIG. 1B illustrates a more preferable shape as the configuration of the sector 100. When the actuating member 115 moves in the clockwise direction (clockwise), as described above, it enters the swing region 112 from the acceleration region 111 and swings the sector 100 to a predetermined position. In general, as shown in FIG. 1A, the cam groove is formed with a groove width that allows the operation member 115 serving as a cam follower to move. However, in the case of the present sector 100, when the actuating member 115-2 that has moved in the clockwise direction is returned to the counterclockwise direction CCW, a large load is applied at the position (115-1) from the swinging region 112 to the acceleration region 111, and deformation occurs. To do. In order to alleviate this, the portion indicated by the oblique lines 116 is deleted to increase the groove width. When the shape of the through hole 110 is changed in this way, the operation member 115 can smoothly reciprocate. In the through hole 110 formed in this way, the operating member 115 passes through different paths in the forward path and the return path.

  The shutter device described below is a shutter device that uses the sector configuration described in FIG. In FIG. 1, the case where one sector is moved is shown for easy understanding of the explanation. However, the shutter device shown below is combined so as to move a plurality of sectors at the same time. Form a state.

  Hereinafter, a shutter device according to an embodiment will be described with reference to the drawings. FIG. 2 is a view showing a state in which the shutter device 1 according to the present invention is in a fully opened state. FIG. 3 is a diagram showing a part of the configuration included in the shutter device 1 of FIG. FIG. 4 is a plan view showing the positional relationship between the shutter substrate and the motor provided in the shutter device of FIG. Further, FIG. 5 is a view showing the shutter device 1 in a fully closed state. FIG. 6 is a view showing the shutter device 1 in the small aperture state.

  First, in FIG. 2, the shutter device 1 is a shutter device having three sectors. The shutter device 1 includes a shutter substrate 3 and three sectors 10, 20, and 30. Sector 10 is a first shutter blade, and sector 20 is a small aperture blade having a small aperture hole. Sector 30 is a second shutter blade. In the shutter device 1, the first sector 10 and the second sector 20 are sectors provided with the above-described novel through holes.

  In FIG. 2, in order to easily check each sector, a portion relating to the first sector 10 is indicated by a solid line, a portion relating to the second sector 20 is indicated by a long broken line, and a portion relating to the third sector is indicated by a dotted line. A shutter opening 4 is formed at the center of the shutter substrate 3.

  The first sector 10 is configured to be swingable about a fixed shaft 11 and includes a through hole 12. The second sector 20 is configured to be swingable about a fixed shaft 21, has a through hole 22, and has a small aperture 23. The third sector 30 is configured to be swingable about a fixed shaft 31 and includes a through hole 32. The three through holes 12, 22, 32 are engaged with drive pins 5 as actuating members that swing along an arcuate locus by a step motor (see FIG. 4) as an actuator. That is, one drive pin 5 passes through the three through holes 12, 22, 32, and all sectors 10, 20, 30 are moved to predetermined positions by the movement of the drive pin 5. .

  FIG. 3 is a diagram showing the components shown in FIG. 2 taken out for easy confirmation. (A) shows the first sector 10, (B) shows the second sector 20, and (C) shows the third sector 30. Further, (D) shows an enlarged movement range of the drive pin 5 that moves while drawing an arcuate locus. The position 5-1 is the fully open position shown in FIG. The position 5-2 is the fully closed position shown in FIG. The position 5-3 is the small aperture position shown in FIG. In the present shutter device 1, the sectors 10, 20, 30 form a fully open state, a fully closed state, and a small stop while the drive pin 5 moves in one direction.

  In particular, the through holes 12 and 22 of the first sector 10 and the second sector 20 are provided with the acceleration region described above, and when the drive pin 5 starts moving in the fully opened state shown in FIG. Enables driving. As a result, the drive pin 5 that has been sufficiently accelerated enters the swing region, and the shutter opening 4 is closed at high speed. This will be clarified in the description of the operation described later. FIG. 3D shows a step motor 7 that drives the drive pin 5 and an arm portion 8 that extends from the step motor 7. The drive pin 5 is fixed to the other end of the arm portion 8. Therefore, when the rotor shaft of the step motor 7 rotates within a predetermined range, the drive pin 5 at the tip of the arm portion 8 swings on the arc as shown in the figure.

  FIG. 4 is a diagram schematically showing the arrangement relationship between the shutter substrate 3 and the step motor 7 included in the shutter device 1 shown in FIG. 2 in plan view. The step motor 7 includes a rotor 702 and a U-shaped stator 703 on the outer periphery thereof. FIG. 3 shows the end side of the stator 703. Two coils 704 and 705 are wound around the stator 703. These coils 704 and 705 are driven and controlled by a control circuit 706.

  Although the shutter substrate 3 includes the shutter opening 4 as described above, it is not shown in FIG. On the front side of the shutter substrate 3, the above-described three sectors 10, 20, and 30 are arranged along the substrate surface. These sectors are the first sector 10, the second sector 20, and the third sector 30 from the shutter substrate 3 side. The step motor 7 is disposed on the back side of the shutter substrate 3.

  Although the position of the hole cannot be confirmed in FIG. 4, the first sector 10 is engaged with the hole that engages with the fixed shaft 11 provided on the substrate 3 and the drive pin 5 that is connected to the rotor shaft 707 of the step motor 7. It has a through hole. The second sector 20 is provided with a hole that engages with a fixed shaft 21 provided on the substrate 3 and a through hole that engages with the drive pin 5. Similarly, the third sector 30 also includes a hole that fits into the fixed shaft 31 provided on the substrate 3 and a through hole that engages with the drive pin 5. As described above, each of the sectors 10, 20, and 30 swings in a unique locus as the drive pin 5 swings. The operations of these sectors 10, 20, and 30 will become apparent from FIGS.

  An arm portion 8 extending in the radial direction is connected to the rotor shaft 707 of the step motor 7 disposed on the back side of the substrate 3. A drive pin 5 extending from the end of the arm 8 to the opposite side through a fan-shaped opening 708 provided on the shutter substrate 3 side is connected. Through holes provided in each of the sectors 10, 20, and 30 are engaged with the drive pins 5 protruding to the front side. Therefore, when the rotor shaft 707 of the stepping motor 7 rotates, the drive pin 5 moves along with this, and the sectors 10, 20, and 30 swing on a predetermined locus.

  In the shutter device 1, the first sector 10 and the second sector 20 are designed to operate in the same manner as the sector described in FIG. 1. That is, the through holes 12 and 22 provided in the first sector 10 and the second sector 20 include an acceleration region and a swing region. As shown in FIG. 2, the through hole 32 of the third sector 30 extends in a direction crossing the moving direction of the drive pin 5, but the shape of the through hole 32 is a straight line and is connected to the drive pin 5. The shape is light. This will be described with reference to FIG. 2 (fully open), FIG. 5 (fully closed), and FIG. 6 (small aperture).

  In the fully open state of FIG. 2, the drive pin 5 is at the right end of the movement range. At this time, each sector 10, 20, 30 is moved to a position where the shutter opening 4 is opened based on the shape of the through holes 12, 22, 32. When attention is paid to each of the through holes 12 and 22, an arcuate acceleration region is formed in the direction in which the drive pin 5 moves. This will be described with reference to FIG.

  FIG. 7A is an enlarged view showing the positional relationship between the drive hole 5 and the through hole 12 of the first sector 10 and the through hole 22 of the second sector 20 in the fully opened state shown in FIG. . FIG. 7B is an enlarged view showing the positional relationship between the drive hole 5 and the through hole 12 of the first sector 10 and the through hole 22 of the second sector 20 in the fully closed state shown in FIG. . FIG. 7C is a diagram showing a relative positional relationship between the through hole 12 of the first sector 10 and the drive pin 5 so that a change can be confirmed between the fully open state and the fully closed state. Similarly, FIG. 7D is a diagram showing a relative positional relationship between the through hole 22 of the second sector 20 and the drive pin 5 so that a change can be confirmed between the fully open state and the fully closed state.

  In the fully closed state of FIG. 7A, the drive pin 5 is located at the right end. Both the through hole 12 of the first sector 10 and the through hole 22 of the second sector 20 are formed in a shape that does not apply a load to the drive pin 5. In FIG. 7C, the region indicated by α is the acceleration region of the through-hole 12, and the region indicated by β in FIG. 7D is the acceleration region of the through-hole 22. It is molded into a corresponding shape. Therefore, the drive pin 5 can start moving in a no-load state with the position (5-1) as the initial position.

  The drive pin 5 can enter a rocking region continuous with the acceleration regions α and β in a state where acceleration is sufficiently applied. In FIG. 7C, the region indicated by γ is the first swing region of the through hole 12, and the region indicated by δ in FIG. 7D is the first swing region of the through hole 22. That is, as shown in FIGS. 7C and 7D, the drive pin 5 enters the first swing region γ, δ in an accelerated state by following the path of the arrow. Cam grooves for guiding the sectors 10 and 20 to the shutter opening are formed in the first swing regions γ and δ. Therefore, the sectors 10 and 20 can be swung at high speed to quickly change from the fully open state of FIG. 7A to the fully closed state of 7B. Since the shutter device 1 includes the third sector 30, in the actual fully closed state, the three sectors cooperate to form the fully closed state shown in FIG.

  Further, a second swing region for forming the small aperture state shown in FIG. 6 is provided continuously to the first swing regions γ and δ of the through holes 12 and 22 of the first and second sectors 10 and 20. Further formed. In the second swing region, cam grooves for swinging the first and second sectors 10 and 20 are formed in order to form a small aperture state. Therefore, when the drive pin 5 advances from the position (5-2) shown in FIG. 7B to the position (5-3), the small aperture state shown in FIG. 6 is formed. As can be seen from FIG. 7, the shape of the through holes 12 and 22 for guiding the drive pin 5 from the small stop to the fully closed state is a normal cam groove shape. When the sector is moved at a high speed when the small aperture is fully closed, an acceleration region can be provided at the end.

  Further, with reference to FIGS. 7C and 7D, the path of the drive pin 5 when returning from the fully closed state to the fully open state will be described. When returning from the fully closed state of FIG. 5 to the fully open state of FIG. 2, the drive pin 5 returns from the right diagram to the left diagram in FIGS. 7C and 7D. At that time, the load on the drive pin 5 is increased in the hatched portions 121 and 221 in both the through holes 12 and 22. Therefore, in this shutter device 1, the portions 121 and 221 are scraped off to increase the groove width. Therefore, the drive pin 5 can return to the fully closed position smoothly.

  The shutter device 1 includes another configuration for speeding up sector movement. This point will be described. In the second sector 20 shown in FIG. 3 (B), a cutout hole 25 formed by cutting out the sector is formed separately from the small aperture opening 23. This hollowing hole 25 is formed in a region that does not affect the opening / closing of the shutter opening or the aperture even if the sector 20 swings as shown in FIG. 2 (fully open), FIG. 5 (fully closed), and FIG. 6 (small aperture). Yes. Thus, by forming the lightening hole 25 in the sector 20, it is possible to reduce the weight and increase the speed of movement. In particular, the sector 20 needs a certain area to provide the small aperture 23 and tends to be heavier than other sectors. However, an increase in weight can be suppressed by forming the hole in this way. Of course, the same hole as described above may be formed in another sector.

  As described above, since the shutter device 1 includes the acceleration region and the swing region in the through hole, the sector can be moved at high speed to form a fully closed state. Therefore, the shutter speed can be increased. Further, by forming different cam grooves in the swinging region, the sector can be moved to a desired position, and a throttle state other than full closure can be easily formed. If it is an optical apparatus incorporating such a shutter device 1, a clear photographed image can be obtained.

  The preferred embodiment of the present invention has been described in detail above. However, the present invention is not limited to the specific embodiment, and various modifications can be made within the scope of the gist of the present invention described in the claims. Deformation / change is possible.

It is the figure shown in order to demonstrate the basic concept employ | adopted by this invention. It is the figure which showed a mode when the shutter apparatus which concerns on this invention exists in a full open state. It is the figure which extracted and showed a part of structure contained in the shutter apparatus of FIG. It is the figure which showed the positional relationship of the shutter board | substrate with which the shutter apparatus of FIG. 1 is equipped, and a motor by planar view. It is the figure which showed a mode when a shutter apparatus exists in a fully closed state. It is the figure which showed a mode when a shutter apparatus exists in a small aperture state. It is the figure which showed the positional relationship of the through-hole of a 1st sector, the through-hole of a 2nd sector, and a drive pin.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Shutter device 3 Shutter board 4 Shutter opening 5 Drive pin 7 Step motor 10 1st sector 11 Fixed shaft 12 Through-hole 20 2nd sector 21 Fixed shaft 22 Through-hole 30 3rd sector 31 Fixed shaft 32 Through-hole (alpha), (beta) Acceleration area | region γ, δ oscillation region

Claims (7)

On a substrate having a shutter opening, a swingable sector that opens and closes the shutter opening, an operating member that drives the sector, and an actuator that drives the operating member are provided.
The sector includes a through hole with which the actuating member engages, and the through hole is formed continuously with an acceleration region in which the actuating member is moved with no load, and the acceleration region. Including a swing region having a cam groove formed so that the sector moves along a predetermined locus ,
The shutter member includes a plurality of sectors, and the operating member is engaged with the through holes of the sectors, and the shutter opening is in a fully open state, a fully closed state, and a small aperture while the operating member is moved in one direction. Formed in the order of
The through hole is formed so that the operating member enters the swing region from the acceleration region and closes the shutter opening at a high speed in the sector when the fully open state is changed to the fully closed state. Shutter device. The actuating member is a driving pin that is fixed to a rotor shaft of the actuator and moves along an arcuate locus, and the acceleration region is formed in an arc shape corresponding to the locus of the driving pin. The shutter device according to 1. The starting point position of the actuating member is set at the end of the acceleration region so that the actuating member is accelerated in the acceleration region, and the swinging region swings the sector to fully close the shutter opening. The shutter device according to claim 1, further comprising a fully-closing cam groove. The sector includes a shutter blade and a small aperture blade, and the swinging region further includes a small aperture cam groove that is positioned continuously to the fully closed cam groove and positions the small aperture blade at the shutter opening. The shutter device according to claim 3. The widening area | region which reduces the load to the said operating member which goes to the said acceleration area | region between the said rocking | swiveling area | region and the said acceleration area | region is formed. Shutter device. 6. The shutter device according to claim 1, wherein the sector has a hollow hole in a region that does not engage with the shutter opening when the sector is moved to a position to close the shutter opening. An optical apparatus comprising the shutter device according to claim 1.

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