JP2011158735A - Barrier mechanism and camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a barrier mechanism capable of preventing the occurrence of malfunction of a barrier blade by preventing an elastic member from being interposed between a rib of a barrier substrate and the barrier blade. <P>SOLUTION: The barrier mechanism 10 includes: a barrier cover 11 having an aperture 11a and arranged closest to a subject side; the barrier substrate 12 having an aperture in the center and arranged closer to an optical lens side than the barrier cover 11 while leaving a fixed space between the barrier cover 11 and the barrier substrate 12; and groups of two barrier blades 13a and 13b, 14a and 14b, and 15a and 15b provided on the barrier cover 11. The barrier substrate 12 has the ribs 12c and 12d regulating movement of the barrier blade in a shaft direction of a supporting shaft 11b. The barrier blade 13a located closest to the optical lens side is arranged closer to the optical lens side than apexes of the ribs 12c and 12d, and the other barrier blades 14a and 15a are arranged closer to the subject side than the apexes of the ribs 12c and 12d. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a barrier mechanism that protects an objective surface of an optical system in an optical apparatus such as a camera and protects the optical system from contamination by dust or fingers, and in particular, a camera having a moving lens barrel driven by a motor, for example, a digital camera , Portable information terminals, image input devices, and the like.

  Conventionally, a barrier mechanism that is disposed in front of an optical lens and protects the lens is known. As an example of this barrier mechanism, a disk-shaped frame having an opening serving as a window for opening an effective optical path of the optical lens in the center, and a barrier cover disposed on the most object side, and the opening substantially in the center A disk-shaped frame with an opening of the same shape, which is spaced around the barrier cover and positioned on the optical lens side of the barrier cover, and rotates on one spindle between the barrier cover and the barrier substrate A barrier blade group consisting of three or more barrier blades that are freely supported, and a pair of barrier blades that are paired with the barrier blade group and that are rotatably supported on one spindle between the barrier cover and the barrier substrate A barrier blade group including barrier blades is known, and the barrier mechanism as a whole has at least six barrier blades.

  The barrier blade group described above has a combination in which the metal barrier blade A, the mold resin barrier blade B, and the metal barrier blade C are arranged in this order in the optical axis direction of the optical lens. The other barrier blades B and C are driven to rotate about the support shaft, and the other barrier blades B and C are configured to rotate about the support shaft following the rotation drive of the barrier blade A. As a barrier mechanism, the barrier blades of each of the barrier blade groups rotate and enter the effective optical path of the optical lens to block the effective optical path and protect the optical lens, and the barrier blade groups are outside the effective optical path of the optical lens. Is a barrier mechanism that is in a barrier open state in which an effective optical path is opened by rotating and retreating the barrier blades, and for each barrier blade group, an elastic member A for rotating the barrier blades in one direction, stronger elasticity than the elastic member A An elastic member B that acts by force to rotate the barrier blade in a direction opposite to the rotation direction by the elastic member A, and a barrier that interrupts the elastic force of the elastic member B from acting on the barrier blade by being driven by an external force. Drive members are provided, and the barrier blade groups, elastic members A, elastic members B, and barrier drive members are arranged symmetrically with respect to the center point of the barrier mechanism What is, for example disclosed in "Patent Document 1".

  This will be specifically described below with reference to the drawings. In the barrier mechanism shown in FIG. 7, a guide shaft 1 a of the barrier cover 1 is inserted into a hole formed in the base of each barrier blade 3, 4, 5. The elastic member 6 disposed above the barrier blade 3 has one of its arms locked on the barrier blade 3 and the other formed on the barrier substrate 2, and is in a direction to close the barrier with respect to the barrier blade 3. A rotational biasing force is applied. The tip of the guide shaft 1a is in contact with the bottom surface 2c of the barrier substrate 2, and the height of the blade chamber of the barrier mechanism is determined by the guide shaft 1a and the bottom surface 2c. Ribs 2 a and 2 b are formed on the barrier substrate 2, and each rib 2 a and 2 b constitutes a receiving surface of the barrier blade 3. The coils constituting the elastic member 6 are all biased toward the rib 2a side, and the elastic member 6 may not be dropped between the rib 2a and the barrier blade 3 and may be sandwiched between the rib 2a and the barrier blade 3. Therefore, the loss of closing force does not occur and the risk of malfunction of the barrier blades is low.

  In the barrier mechanism described above, an appropriate gap is provided between the rib of the barrier substrate and the barrier blade A in order to operate the barrier blade smoothly. Due to the presence of this gap, a part of the elastic member A falls between the ribs of the barrier substrate and the barrier blades A, and is easily sandwiched between the ribs of the barrier substrate and the barrier blades A. If the elastic member A is sandwiched between the ribs of the barrier substrate and the barrier blade A, the closing force is lost, which causes a malfunction of the barrier blade. However, this gap needs to be the same as or larger than a part of the elastic member A. If the gap is small, the operation of the barrier blades will be defective. Was difficult.

  This will be specifically described below with reference to the drawings. FIG. 8 shows a barrier mechanism similar to that in FIG. 7, and the gap between the ribs 2 a, 2 b and the barrier blade 3 is set to be equal to or larger than one coil of the elastic member 6. As described above, the elastic member 6 is biased to the rib 2a side, but when the close contact degree of the coil of the elastic member 6 changes, a part of the coil falls between the rib 2a and the barrier blade 3 and is shown in FIG. As described above, a part of the elastic member 6 is sandwiched between the rib 2a and the barrier blade 3. In this state, the ribs 2a and 2b do not function as the receiving surface of the barrier blade 3, and there is a high risk that a loss occurs in the closing force and malfunction of the barrier blade occurs.

  The present invention solves the above-described problems, and provides a barrier mechanism capable of preventing the elastic member from being sandwiched between the ribs of the barrier substrate and the barrier blades, thereby preventing the malfunction of the barrier blades. With the goal.

The invention according to claim 1 is a barrier mechanism disposed on the front surface of the optical lens, the barrier mechanism having an opening for opening an effective optical path of the optical lens in the center and disposed closest to the subject. A barrier substrate having an opening substantially in the same shape as the opening at the center and disposed at a certain distance from the barrier cover on the optical lens side with respect to the barrier cover, and a support shaft provided on the barrier cover Two or more barrier blades that are rotatably supported, at least one of which is driven to rotate by driving means, and the other barrier blades are rotated and driven by the barrier blades. A barrier closed state in which the effective optical path is blocked and the optical lens is protected by causing the barrier blades to enter the effective optical path. Wherein the barrier arrangement comprising a barrier open state to open the effective optical path by retracting the respective barrier blades to,
The barrier substrate has a rib for restricting the movement of the barrier blade in the axial direction of the support shaft, and the barrier blade located closest to the optical lens is disposed closer to the optical lens than the apex of the rib. The other barrier blades are arranged on the subject side with respect to the apex of the rib.

  According to a second aspect of the present invention, in the barrier mechanism according to the first aspect, the barrier blade further rotationally driven is restricted by the driving means from moving in the axial direction of the support shaft, and the other barrier blade is The movement of the support shaft in the axial direction is restricted by the rib.

  The invention according to claim 3 is the barrier mechanism according to claim 1 or 2, wherein the barrier blade group further includes a metal barrier blade, a mold resin barrier blade, and a metal barrier blade in the optical axis direction of the optical lens. It has the combination arranged in order.

  According to a fourth aspect of the present invention, there is provided an imaging apparatus having an imaging optical lens as the optical lens, and the barrier mechanism according to any one of the first to third aspects, wherein the barrier mechanism is a part of the imaging optical lens. Among these, the camera is arranged on the subject side further than the one located closest to the subject side.

  According to the present invention, even if an appropriate gap is provided between the rib and the barrier blade in order to operate the barrier blade smoothly, the coil constituting the driving means is positioned on the barrier blade arranged closest to the optical lens. In addition, the driving means is not sandwiched between the rib and the barrier blade, and the loss of the closing force due to the sandwiching is not generated, so that the malfunction of the barrier blade can be prevented.

It is a schematic perspective view in the barrier blade closed state of the barrier mechanism which can apply one Embodiment of this invention. It is a schematic perspective view in the barrier blade open state of the barrier mechanism which can apply one Embodiment of this invention. It is a schematic plan view of the barrier mechanism which can apply one Embodiment of this invention. It is a schematic sectional drawing in the ideal state explaining arrangement | positioning of each barrier blade | wing, rib, and elastic member in one Embodiment of this invention. It is a schematic sectional drawing in the actual use condition explaining arrangement of each barrier blade, rib, and elastic member in one embodiment of the present invention. It is a schematic perspective view which shows the camera carrying the barrier mechanism shown by one Embodiment of this invention. It is a schematic sectional drawing in the ideal state explaining the arrangement | positioning of each barrier blade | wing, a rib, and an elastic member in the conventional barrier mechanism. It is a schematic sectional drawing in the actual use state explaining arrangement | positioning of each barrier blade | wing, a rib, and an elastic member in the conventional barrier mechanism.

  1 and 2 show a barrier mechanism employing an embodiment of the present invention. The barrier mechanism 10 disposed on the front surface of the optical lens is a disc-shaped frame having an opening 11a for opening an effective optical path of the optical lens in the center, and the barrier cover 11 disposed closest to the subject, and in the center. A disk-shaped frame having an opening substantially the same shape as the opening 11a, a barrier substrate 12 disposed at a predetermined distance from the barrier cover 11 and closer to the optical lens than the barrier cover 11, and the barrier cover 11 and the barrier substrate 12, barrier blades 13 a, 14 a, and 15 a that are rotatably supported on one support shaft, and barrier blades 13 b, 14 b, and 15 b that are paired with the barrier blades 13 a, 14 a, and 15 a.

  The barrier blades 13a, 14a, and 15a are arranged in the order of 13a, 14a, and 15a from the optical lens side in the optical axis direction of the optical lens. The barrier blade 13a is driven to rotate around the support shaft, and the other barrier blades 14a, Reference numeral 15a is configured to rotate following the rotation of the barrier blade 13a. The barrier blades 13b, 14b, and 15b are also arranged in the order of 13b, 14b, and 15b from the optical lens side in the optical axis direction of the optical lens. The barrier blade 13b is driven to rotate around the support shaft, and the other barrier blades 14b, 15b is configured to be driven to rotate. The barrier mechanism 10 blocks barriers 13a, 13b, 14a, 14b, 15a, and 15b into the effective optical path of the optical lens, thereby closing the opening 11a and blocking the effective optical path to protect the optical lens. As shown in FIG. Further, by retracting the barrier blades 13a, 13b, 14a, 14b, 15a, and 15b outside the effective optical path of the optical lens, the opening 11a is opened, the effective optical path is opened, and the barrier open state shown in FIG. 2 is obtained.

  Next, an opening / closing mechanism that opens and closes the opening 11a by moving the barrier blades 13a, 13b, 14a, 14b, 15a, and 15b will be described. The opening / closing mechanism closes the elastic member 16a and the barrier blades 13b, 14b, and 15b as driving means for applying an urging force to the barrier blade 13a to rotate the barrier blades 13a, 14a, and 15a in the direction for closing the barrier blades. The elastic member 16a that applies an urging force to rotate in the direction to be applied to the barrier blade 13b and the elastic member (not shown) disposed opposite to each other through the opening 11a, and acts with a stronger elastic force than the elastic member 16a, and the barrier blade 13a, An elastic member 17a for rotating 14a, 15a in a direction opposite to the rotation direction by the elastic member 16a, and a rotating direction of the barrier blades 13b, 14b, 15b by an elastic member not shown by acting with a stronger elastic force than an elastic member (not shown) Elastic member 17b for rotating in the opposite direction to the elastic member 17a by being driven by an external force The barrier driving member 18a that interrupts the action of the elastic force on the barrier blades 13a, 14a, and 15a, and the elastic force of the elastic member 17b that acts on the barrier blades 13b, 14b, and 15b by being driven by an external force are interrupted. It has a barrier driving member 18b and the like.

  As shown in FIG. 3, the barrier blades 13a, 14a, and 15a are rotatably supported by the support shaft 11b between the barrier cover 11 and the barrier substrate 12, and although not shown, the barrier blades 13b, 14b, Similarly, 15b is rotatably supported on the support shaft 11c. The barrier blades 13a and 13b are made of a metal plate, and examples of the material include stainless steel, aluminum, iron, and titanium. The plate thickness is preferably thin enough to maintain rigidity, and is preferably about 0.2 to 0.5 mm. The barrier blades 14a and 14b are made of a molded resin plate material, and examples of the material include general mold resins such as polycarbonate. The plate thickness is preferably thin enough to maintain rigidity, and is preferably about 0.5 to 1.0 mm. The barrier blades 15a and 15b are made of a metal plate material such as stainless steel, aluminum, iron, and titanium, like the barrier blades 13a and 13b, and the plate thickness is preferably thin enough to maintain rigidity. About 0.5 mm is preferable. With this configuration, the thickness of the optical lens in the optical axis direction can be reduced.

  The elastic member 16 a is a torsion coil spring attached to a support shaft 11 b provided on the barrier cover 11 between the barrier cover 11 and the barrier substrate 12, one end of which is fixed to the barrier cover 11 and the other end is fixed. Locked by a hook portion 13a1 provided on the barrier blade 13a, a rotational force is applied in a direction to enter the barrier closed state on the barrier blade 13a. The elastic member (not shown) attached to the support shaft 11c is also a torsion coil spring similar to the elastic member 16a, one end of which is fixed to the barrier cover 11 and the other end is connected to a hook portion (not shown) provided on the barrier blade 13b. The rotational force is applied to the barrier blade 13b so that the barrier blade 13b is in the closed state.

  The elastic member 17a is a torsion coil spring which is attached to the support shaft 21a shown and has a stronger elastic force than the elastic member 16a. One end of the elastic member 17a is locked to the locking portion 12a provided on the barrier substrate 12 and the other end is locked. The barrier driving member 18a is engaged with the barrier blade 13a to apply a rotational force in a direction in which the barrier is opened. The elastic member 17b attached to the support shaft 21b is also a torsion coil spring similar to the elastic member 17a. One end of the elastic member 17b is locked to the locking portion 12b and the other end is locked to the barrier driving member 18b. A rotational force in the direction of opening the barrier is applied to 13b.

  The barrier drive member 18a is a lever arm that is rotatably supported by a support shaft 20a provided on the barrier substrate 12, and receives an elastic force by locking the elastic member 17a at one end thereof. The barrier blades 13a that are in contact with the barrier blade 13a act so as to be in the barrier open state. A pin 19a to which an external force is applied projects from one end side of the barrier driving member 18a. Similarly to the barrier drive member 18a, the barrier drive member 18b is a lever arm rotatably supported by the support shaft 20b. The elastic member 17b is engaged at one end thereof to receive an elastic force, and this elastic force is applied to the other end. The abutting barrier blade 13b is caused to act so as to be in the barrier open state. A pin 19b similar to the pin 19a protrudes from one end side of the barrier driving member 18b.

  With the above-described configuration, the barrier mechanism 10 opens and closes the opening 11a in the same manner as the barrier mechanism 1 disclosed in Japanese Patent Application Laid-Open No. 2007-102086. However, when performing this opening / closing operation, as described in the section “Problems to be Solved by the Invention”, the elastic member 16a falls between the rib formed on the barrier substrate 12 and the barrier blades 13a. When the portion is sandwiched, the closing force is lost, and the risk of malfunction of the barrier blades 13a, 13b, 14a, 14b, 15a, 15b is increased. An embodiment of the present invention that avoids this problem will be described below.

  4 and 5 are schematic views of the base portions of the barrier blades 13a, 14a, and 15a when the barrier mechanism 10 is cut at the center of the support shaft 11b as viewed from the outside of the barrier mechanism 10, and FIG. FIG. 5 shows a state where the degree of close contact of the coil of the elastic member 16a and the gap between the ribs 12c and 12d and the barrier blade 13a are changed.

  Each of the barrier blades 13a, 14a, 15a is configured to be rotatable by locking a hole formed at each base to the support shaft 11b, and downward ribs 12c, 12d are integrated with the barrier substrate 12, respectively. Is formed. The tip of the support shaft 11b is in contact with the bottom surface 12e of the barrier substrate 12, and the height of the blade chamber of the barrier mechanism 10 is determined by the support shaft 11a and the bottom surface 12e. Since the barrier substrate 12 has ribs 12c and 12d formed therein, the hole diameter formed at the base of the barrier blade 13a is larger than the circular diameter formed by the ribs 12 and 12d. The ribs 12c and 12d constitute the receiving surface of the barrier blade 14a. All of the coils constituting the elastic member 16a are offset to the rib 12c side.

  Even if an appropriate gap is provided between the ribs 12c, 12d and the barrier blade 13a in order to smoothly operate the barrier blades 13a, 14a, and 15a, the coil constituting the elastic member 16a is on the barrier blade 13a. As shown in FIG. 5, even if the close contact degree of the coil of the elastic member 16a and the gap between the ribs 12c, 12d and the barrier blade 13a change, the gap between the ribs 12c, 12d and the barrier blade 13a remains. If it is smaller than the wire diameter of the coil constituting the elastic member 16a, the elastic member 16a will not be sandwiched between the ribs 12c, 12d and the barrier blade 13a, and the loss of the closing force due to the pinching will not occur. Occurrence of malfunctions can be prevented.

  FIG. 6 shows a camera equipped with the barrier mechanism 10 described above. In the figure, a camera 30 is a compact camera having a retractable lens barrel (a system in which the lens barrel is housed in the main body when not photographing), and a photographing optical lens that captures image information on the front surface of the main body 31. The lens portion 32 is integrally provided with the main body 31. The above-described barrier mechanism 10 is provided on the subject side (front) of the lens unit 32. Near the center of the front surface of the main body 31, a distance measuring unit 33 for measuring the distance to the subject is provided, and in addition, a flash unit 34, a release button 35, and a power switch 36 are provided.

  In the camera 30 described above, when the power switch 36 is pressed for activation, the lens barrel moves forward in the lens unit 32, and an opening operation in which the barrier mechanism 10 changes from the closed state to the open state is performed, and photographing is performed. It becomes possible. Further, when the power switch 36 is pressed to stop, the lens barrel is retracted together with the retracted lens unit 32 and stored in the main body 31, and the closing operation in which the barrier mechanism 10 changes from the open state to the closed state is performed. As a result, the camera 30 enters a standby state. By using the barrier mechanism 10 for the camera 30, it is possible to prevent the occurrence of malfunctions of the barrier blades and to perform good photographing continuously over a long period of time.

DESCRIPTION OF SYMBOLS 10 Barrier mechanism 11 Barrier cover 11a Opening part 11b Support shaft 12 Barrier board | substrate 12c, 12d Rib 13a, 13b, 14a, 14b, 15a, 15b Barrier blade | wing 16a Drive means (elastic member)
32 Shooting optical lens (lens)

JP 2007-102086 A

Claims (4)

A barrier mechanism disposed on the front surface of the optical lens, the barrier cover having an opening for opening an effective optical path of the optical lens at the center and disposed closest to the subject; and the opening at the center approximately Three pieces having an opening of the same shape, a barrier substrate disposed at a certain distance from the barrier cover on the optical lens side with respect to the barrier cover, and rotatably supported by a support shaft provided in the barrier cover The effective light path includes at least one of the above barrier blades, at least one of which is rotated by driving means, and the other barrier blades are rotated by the barrier blades driven to rotate. When the barrier blades enter the inside, the effective optical path is interrupted and the barrier is closed to protect the optical lens, and the barrier blades are placed outside the effective optical path. In the barrier mechanism as a barrier open state to open the effective optical path by avoided,
The barrier substrate has a rib for restricting the movement of the barrier blade in the axial direction of the support shaft, and the barrier blade located closest to the optical lens is disposed closer to the optical lens than the apex of the rib. The other barrier blades are arranged closer to the subject side than the apexes of the ribs. The barrier mechanism according to claim 1,
The barrier blades that are rotationally driven are restricted by the driving means from moving in the axial direction of the support shaft, and the other barrier blades are restricted from moving in the axial direction of the support shaft by the ribs. And barrier mechanism. The barrier mechanism according to claim 1 or 2,
The barrier blade group has a combination of a metal barrier blade, a mold resin barrier blade, and a metal barrier blade arranged in this order in the optical axis direction of the optical lens.   An imaging apparatus having an imaging optical lens as the optical lens, and the barrier mechanism according to claim 1, wherein the barrier mechanism is located closest to the subject among the imaging optical lenses. The camera is further arranged on the subject side.

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