JP2013088783A - Diaphragm device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a diaphragm device which achieve improvement in assembling property of a drive motor and space saving.SOLUTION: A diaphragm device includes: a base 2; a diaphragm mechanism 3 composed of two shading plates 31 and 32 capable of oppositely sliding along the base, provided with notches 31e and 32e cooperating with opposite end surfaces 31c and 32c to form a diaphragm 38, and adjusting the diaphragm according to the sliding in an approaching or separating direction; and a drive mechanism 4 composed of a drive motor 41 attached to the base through a supporting plate 44, a face gear 43 rotatably supported by a supporting shaft 45 raised on the supporting plate and engaged with a flat gear 42 of the drive motor, drive pins 51 and 52 raised at predetermined positions on one side end surface 43b of the face gear and engaged with first pin holes 31h and 32h provided on the shading plates to bring the opposite two shading plates close to/separate from each other according to rotations of the face gear, and energizing means 47 provided in a contracted state between the base and the face gear to press the face gear on the flat gear.

Description

  The present invention relates to a diaphragm device suitable for use in a projector or a projector that projects an image, text, or the like on a transmissive or reflective screen.

  For example, a liquid crystal projector (projector) equipped with a liquid crystal panel or a DMC projector (projector) equipped with a DMC (digital micromirror device) is used in the introduction and explanation of commercial products, or in lectures and presentations. Has been. Among these projectors, in a liquid crystal projector, the amount of illumination light applied to the liquid crystal panel from the light source lamp by the aperture device when not projecting is weakened to prevent deterioration of the liquid crystal panel.

  As the diaphragm device, the two drive members are each formed by a flat fan having a substantially fan shape and are arranged in mesh with each other, and a light shielding plate as a light shielding means is fixed to each of these flat gears, and one of the flat gears is fixed. The spur gear fixed to the rotating shaft of the drive motor is engaged, and the shaft hole of the rotating shaft of the other spur gear is made into an elongated hole so that the engagement with one spur gear can be adjusted. The back spring is reduced by pressing against one of the spur gears with a coil spring placed in the position, and the two spur gears (drive members) are rotated in opposite directions by the drive motor to actuate the two light shielding plates relatively. There is a diaphragm device that controls the opening (see, for example, Patent Document 1).

JP 2008-145949 A (page 5-6, FIG. 1)

  However, the diaphragm device described in the above-mentioned patent document 1 is arranged in the axial direction of the drive motor in order to smoothly and reduce backlash when the spur gear of the drive motor is engaged with one spur gear of the drive member. Assembly accuracy is required, and it takes time to assemble the drive motor. Further, since a flat gear is used, it is necessary to arrange the rotation shafts of the respective flat gears side by side, and a coil in which the other flat gear is arranged on the side to reduce backlash of the driving member. Since the spring is pressed against one of the spur gears, the space is inevitably increased.

  The present invention has been made to solve such problems, and it is an object of the present invention to provide an aperture device that improves the assembly of the drive motor and saves space.

  In order to solve the above-mentioned problems, the means employed by the present invention is a diaphragm device comprising a base and two first light shielding plates slidable facing each other along the base. A notch for forming a diaphragm is provided in cooperation with the opposing end surfaces of the first light-shielding plate, and the diaphragm is adjusted according to sliding of the two first light-shielding plates toward or away from each other. A diaphragm mechanism, a drive motor attached to the base via a support plate, and a rotary gear supported by a support shaft standing on the support plate and rotatably engaged with a flat gear attached to the drive motor. The face gear and the face gear are erected at predetermined positions on one end face of the face gear and engaged with the first pin holes respectively provided in the two first light shielding plates to rotate the face gear. Two first drive pins for bringing the two first light-shielding plates close to or away from each other, In that a drive mechanism including a biasing means for pressing the compressed state has been spur gear with face gear between the micro base and face gear.

  The two light shielding plates form a stop by a notch formed in each of the opposing end surfaces. When the face gear is rotated by the drive motor, the two drive pins are rotated along with this, and the corresponding two light shielding plates are slid along the base so as to approach or separate from each other. When the two light shielding plates are separated from each other, the aperture is opened. As a result, the aperture is adjusted from fully open to the minimum aperture.

  By using the face gear as the gear provided with the drive pin, when the drive motor is engaged with the spur gear, the allowance in the axial direction of the drive motor is increased, and attachment is facilitated. Further, by urging the urging means between the base and the face gear and pressing the face gear against the flat gear to remove backlash, space saving can be achieved compared to the conventional diaphragm device.

  In the diaphragm device, the two first drive pins are arranged on a straight line passing through the rotation center of the face gear and symmetrically with respect to the rotation center. Thus, by arranging the two first drive pins on a straight line passing through the rotation center of the face gear and at a symmetrical position with respect to the rotation center, the faces of the two first drive pins are arranged. By appropriately changing the radial distance from the rotation center of the gear, the sliding length of the first light shielding plate, that is, the light shielding amount can be optimally adjusted.

  In the above-described diaphragm device, it is desirable that the base is formed with two arc-shaped first bases through which the two first drive pins respectively pivotably pass.

  In this way, by forming two arc-shaped first base guide holes through which the two first drive pins are pivotably inserted in the base, two light shields are provided above the base. The drive mechanism can be arranged on the plate and below the base. The two light shielding plates that form the diaphragm are slidably mounted on the upper surface of the base, and each light guide plate is inserted into each base guide hole provided in the base by passing each drive pin provided in the face gear. The light shielding plate guide hole is engaged. In accordance with the rotation of the face gear, the diaphragm is adjusted by moving the corresponding light shielding plate closer or away from each other. Thereby, size reduction of an aperture device can be achieved.

  In the above diaphragm apparatus, the first light shielding plate is provided with two first light shielding plate guide holes parallel to the sliding direction, and is fixed to the base so that each of the first light shielding plates can slide in the light shielding plate guide holes. It is desirable to be guided by two guide pins penetrating and slid linearly along the base.

  Guide pins are slidably penetrated through two light shielding plate guide holes provided in parallel along the sliding direction in the first light shielding plate forming the diaphragm, and these guide pins are fixed to the upper surface of the base. . The light shielding plate slides linearly on the upper surface of the base along the sliding direction along two parallel guide pins. As a result, the two opposing light shielding plates can be slid linearly and smoothly, light leakage from the overlapping end faces can be prevented, and the diaphragm can be adjusted accurately.

  In the diaphragm device, the diaphragm mechanism is disposed on the outer side of the two first light shielding plates and slides along the base together with the first light shielding plate to move the outer side of the first light shielding plate. Two second light shielding plates for shielding light are further provided, and the drive mechanism is erected at a predetermined position on one side end face of the face gear and is engaged with a second pin hole provided in each of the second light shielding plates. In addition, it is desirable to further include a second drive pin for bringing the two second light shielding plates close to or away from each other together with the first light shielding plate according to the rotation of the face gear.

  A second light-shielding plate is provided on each of the outer sides of the two first light-shielding plates forming the diaphragm, and the first and second drive pins provided on the face gear are provided on these light-shielding plates. The two second light-shielding plates are slid together with the two first light-shielding plates that form the diaphragm by engaging with the plate guide holes. The two second light shielding plates cover the outer sides of these light shielding plates and shield the light from the outer sides when the two first light shielding plates are brought close to each other and the diaphragm is minimized. .

  Since the four light shielding plates are interlocked to shield the outer side, the length of the entire diaphragm device in the horizontal direction can be made shorter than the case of using only two light shielding plates. For this reason, it is possible to reduce the overall dimensions of a projector, a projector, and the like that are equipped with the aperture device, and to reduce their size.

  In the diaphragm device, the two second drive pins are arranged on a straight line passing through the rotation center of the face gear and symmetrically with respect to the rotation center. In this way, by arranging the two second drive pins on a straight line passing through the rotation center of the face gear and at a symmetrical position with respect to the rotation center, the rotation center of the second drive pin is removed. By appropriately changing the distance in the radial direction, the sliding length of the second light shielding plate can be optimally adjusted.

  In the diaphragm device, it is desirable that the base further includes two arc-shaped second base guide holes through which the two second drive pins are pivotably passed.

  In this way, by forming two arc-shaped second base guide holes through which the two second drive pins are pivotably inserted in the base, two second drive pins are formed above the base. The two light shielding plates and the driving mechanism thereof can be arranged below the base. The two second light-shielding plates that shield the outer side are slidably mounted on the upper surface of the base, and pass through each drive pin provided in the face gear in each base guide hole provided in the base. And engage with the light guide plate guide hole of each light shield plate. In accordance with the rotation of the face gear, the diaphragm is adjusted by moving the corresponding light shielding plate closer to or away from the light shielding plate. Thereby, size reduction of an aperture device can be achieved.

  In the diaphragm device, the second light-shielding plate is provided with a second light-shielding plate guide hole parallel to the first light-shielding plate guide hole along the sliding direction, and is fixed to the base so that the second light-shielding plate is fixed. It is desirable that the light guide is guided by guide pins that slidably pass through the light shielding plate guide holes, and slides linearly along the base together with the first light shielding plate.

  Guide pins are slidably passed through two light shielding plate guide holes provided in parallel to the first and second light shielding plates along the sliding direction, and these guide pins are fixed to the upper surface of the base. . The two first and second drive pins provided in the face gear are passed through the base guide holes provided in the base, respectively, and engaged with the pin holes of the respective light shielding plates.

  As each drive pin rotates in conjunction with each other, each first light shielding plate slides linearly along the sliding direction on the upper surface of the base along two parallel guide pins. Each of the light shielding plates 2 slides with the first light shielding plate along the guide pins on the upper surface of the horizontal portion of each first light shielding plate. Thereby, the first and second light shielding plates can be slid linearly and smoothly, and leakage of light from between the overlapping end surfaces of the opposing first light shielding plates can be prevented. The aperture can be adjusted accurately, and light from the outer side of the first light shielding plate is shielded by the second light shielding plate.

  In the diaphragm device, the first light shielding plate in the case of only the first light shielding plate, or the first light shielding plate and the second light shielding plate in the case of having the first light shielding plate and the second light shielding plate, The vertical cross-sectional shape is substantially L-shaped, and has a flat horizontal portion and a flat vertical portion. The horizontal portion is slidable along the base, and is formed on the vertical portion of the first light shielding plate. It is desirable that the notch is formed.

  As described above, the first light-shielding plate in the case of only the first light-shielding plate, or the longitudinal section of the first light-shielding plate and the second light-shielding plate in the case of having the first light-shielding plate and the second light-shielding plate. By forming the shape substantially L-shaped, allowing the horizontal portion to slide along the base, and forming the notch in the vertical portion, the entire diaphragm device can be miniaturized.

  As described above, the diaphragm device according to the present invention includes the base and the two first light shielding plates that are slidable facing each other along the base, and the two first light shielding plates are opposed to each other. A diaphragm mechanism that is provided with a notch that cooperates with the end face to form a diaphragm, and the diaphragm is adjusted according to sliding in the direction in which the two first light shielding plates approach or separate from each other, and a support plate on the base A drive motor that is attached to the support plate, a face gear that is rotatably supported by a support shaft that is erected on the support plate, and that is rotated by meshing with a flat gear attached to the drive motor, and a face gear The two first light shielding members according to the rotation of the face gear by being erected at a predetermined position on one end face and engaging with first pin holes respectively provided in the two first light shielding plates. Two first drive pins that bring the plate close to or away from each other, and are contracted between the base and the face gear. And a drive mechanism including a biasing means for pressing the face gear the spur gear.

  As described above, by using the face gear as the gear provided with the drive pin, when the drive motor is engaged with the spur gear, the tolerance in the axial direction regarding the attachment of the drive motor is increased, and the attachment is facilitated. In addition, the urging means is contracted between the base and the face gear so that backlash is removed by pressing the face gear against the flat gear, thus saving space compared to conventional diaphragm devices. Is planned.

It is a disassembled perspective view of the aperture_diaphragm | restriction apparatus which concerns on one Embodiment of this invention. FIG. 2 is a perspective view when the diaphragm device shown in FIG. 1 is assembled and the diaphragm is fully opened. FIG. 3 is a perspective view when the diaphragm of the diaphragm device shown in FIG. 2 is minimized. FIG. 3 is a top view of the diaphragm device shown in FIG. 1 in a fully opened position of a face gear. FIG. 3 is a top view of the diaphragm device shown in FIG. 2 in a fully opened position of the diaphragm. FIG. 6 is a front view of the diaphragm device shown in FIG. 5. FIG. 5 is a top view of the face gear shown in FIG. 4 at a middle aperture position. FIG. 6 is a top view of the diaphragm device shown in FIG. 5 at a middle diaphragm position. It is a front view of the diaphragm | throttle device shown in FIG. FIG. 5 is a top view of the face gear shown in FIG. 4 at the minimum aperture position. FIG. 6 is a front view of the diaphragm device shown in FIG. 5 at a minimum diaphragm position. It is a front view of the diaphragm | throttle device shown in FIG.

  A mode for carrying out the invention of the diaphragm device of the present invention will be described in detail with reference to FIGS.

  As shown in FIG. 1, the diaphragm device 1 includes a base 2, a slide-type diaphragm mechanism 3 disposed on the upper surface 2 a of the base 2, and a drive disposed on the lower side of the base 2 to drive the diaphragm mechanism 3. It is comprised by the mechanism 4 grade | etc.,.

  The base 2 has a flat upper surface 2a in the left-right direction in the figure, two slit-shaped first base guide holes 2b, 2c and two slit-shaped second bases concentrically in the center. Base guide holes 2d and 2e are formed.

  The base guide hole 2b and the base guide hole 2d are disposed forward from the center, and the base guide hole 2c and the base guide hole 2e are disposed rearward from the center. That is, the base guide holes 2b and 2d and the base guide holes 2c and 2e are symmetrically arranged in the front-rear direction, forming a quadrant arc having a predetermined center angle in the longitudinal direction, for example, a center angle of 90 °. Yes.

  Rails 2f to 2k for smoothly sliding and sliding the diaphragm mechanism 3 are provided on the upper surface 2a of the base 2 in parallel along the longitudinal direction. The rails 2f and 2g are provided in parallel along the longitudinal direction from the position near the left end in the figure of the front base guide holes 2b and 2d to the position near the left end of the upper surface portion 2a, and the rail 2h is provided in the base guide hole 2b. From the position near the right end to the position near the right end of the upper surface portion 2a, it is provided on the same straight line as the rail 2f along the longitudinal direction.

  The rails 2i and 2j are provided in parallel along the longitudinal direction from the position near the right end of the rear base guide holes 2c and 2e in the drawing to the position near the right end of the upper surface portion 2a, and the rail 2k is connected to the base guide hole 2c. From the position near the left end to the position near the left end of the upper surface portion 2a, it is provided on the same straight line as the rail 2i along the longitudinal direction. In addition, an accommodation portion 2m for accommodating the drive mechanism 3 is integrally formed below the base 2.

  The upper surface portion 2a of the base 2 is provided with first guide pins 11 and 12 and second guide pins 13 and 14 for sliding and sliding the diaphragm mechanism 3 smoothly and linearly. The first guide pins 11 and 12 are arranged at a predetermined position in front of the rails 2f and 2g and near the right end of the rail 2f, and the second guide pins 13 and 14 are located behind the rails 2i and 2j and near the left end of the rail 2i. It arrange | positions in a position and is fixed by press-fitting in the hole formed in the upper surface part 2a, respectively.

  The rails 2f, 2g, 2h and the guide pins 11, 12 and the rails 2i, 2j, 2k and the guide pins 13, 14 are centered on the center positions of the base guide holes 2b, 2c and the base guide holes 2d, 2e. The rails 2f, 2g, 2h and the guide pins 11, 12 are arranged in the front, and the rails 2i, 2j, 2k and the guide pins 13, 14 are arranged in the rear.

  The guide pins 11 to 14 have a stepped shape in which the head portion, the shaft portion, and the press-fit portion are sequentially reduced in diameter, and slide the throttle mechanism 3 linearly and smoothly along the longitudinal direction of the base 2. At the same time, the deviation is prevented.

  The slide type diaphragm mechanism 3 includes four light shielding plates 31 to 34. The first light shielding plates 31 and 32 slide in the directions approaching or separating to adjust the size of the diaphragm, that is, the opening area. The second light-shielding plate 33 and the light-shielding plate 34 slide and slide together with the light-shielding plates 31 and 32 to shield the outer sides of the light-shielding plates 31 and 32 when the diaphragm is minimized.

  The light shielding plates 31 to 34 have, for example, a substantially L-shaped vertical cross-sectional shape, and the light shielding plates 31 and 33 have a substantially L shape in which lower portions 31b and 33b are bent at a right angle forward in the figure. The light shielding plates 32 and 34 are substantially L-shaped in which lower portions 33b and 34b are bent at right angles to the rear in the drawing.

  The light shielding plate 31 has a vertical portion 31a as a light shielding portion (hereinafter referred to as a light shielding portion 31a) and a horizontal portion 31b bent to the front side as a sliding portion (hereinafter referred to as a sliding portion 31b). A trapezoidal cutout 31e for forming the diaphragm 38 is formed on the right end surface 31c of the light shielding portion 31a.

  The sliding portion 31b is slidable on the rails 2f, 2g, and 2h in front of the upper surface portion 2a of the base 2, and can slide along the rails 2f and 2g at positions corresponding to the guide pins 11 and 12. Thus, slit-shaped light guide plate holes 31f and 31g having a predetermined length are formed. A slit-shaped pin hole 31h is formed at a predetermined position on the end face 31c side in the front-rear direction in the figure, and the drive pin 51 provided in the face gear 43 of the drive mechanism 4 described later is in the radial direction, that is, the figure. It is slidably penetrated in the middle / front / rear direction.

  In addition, a slit 31 i is formed at a position corresponding to the drive pin 53 that drives the light shielding plate 33 of the sliding portion 31 b so that the drive pin 53 does not interfere when the light shielding plate 33 is driven. Thereby, the light shielding plate 31 can be slid linearly in the left-right direction in the drawing, that is, in the longitudinal direction, in accordance with the rotation of the drive pin 51.

  As shown in FIG. 5, the width of the light shielding plate 31 is slightly longer than half of the length of the upper surface portion 2a of the base 2, and as will be described later, the left end face when the diaphragm is fully opened. 31d is flush with the left end surface of the upper surface 2a, and the right end surface 31c slightly overlaps the opposite end surface 32c of the light shielding plate 32.

  The light shielding plate 32 is formed in a shape symmetrical with the light shielding plate 31 in the front-rear direction and the left-right direction. As shown in FIG. Description is omitted.

  In the light shielding plate 33, the vertical portion 33a is a light shielding portion (hereinafter referred to as a light shielding portion 33a), and the lower horizontal portion 33b bent forward is a sliding portion (hereinafter referred to as a sliding portion 33b). . The horizontal width of the light shielding plate 33 is approximately half the length of the upper surface portion 2a, and the light shielding plate 33 side of the light shielding portion 33a, that is, the right side in the drawing, is largely cut out in a substantially L shape.

  The light shielding plate 33 is disposed in front of the light shielding plate 31, and substantially overlaps with the light shielding portion 31a of the light shielding plate 31 when the diaphragm of the light shielding plate 31 is fully opened, and the right end surface 33c is a trapezoidal cutout 31e of the light shielding plate 31. The end surface 33c slightly overlaps the end surface 31d of the light shielding plate 31 when the aperture is minimized, and the outer side of the light shielding plate 31 is shielded from light. Yes.

  The sliding portion 33b is placed on the sliding portion 31b of the light shielding plate 31 and can slide on the sliding portion 31b. The light shielding portion 33a is in contact with the front surface of the light shielding portion 31a of the light shielding plate 31. It is possible to slide. In the sliding portion 33b, light shielding plate guide holes 33f and 33g are formed at positions corresponding to the light shielding plate guide holes 31f and 31g of the sliding portion 31b of the light shielding plate 31. The lengths of the light shielding plate guide holes 33f and 33g are approximately half the length of the light shielding plate guide holes 31f and 31g.

  The sliding portion 33b is formed with slit-like pin holes 33h in the front-rear direction in the figure at predetermined positions on the end face 33c side, and the drive pin 53 provided in the face gear 43 is in the radial direction, that is, the front-rear direction in the figure. Is slidably penetrated. Further, as shown in FIGS. 1 and 5, the end surface 33 c side of the sliding portion 33 b is cut out in a substantially L shape so as not to interfere with the drive pin 51 that drives the light shielding plate 31. Accordingly, the light shielding plate 33 is slidable linearly in the left-right direction, that is, the longitudinal direction, on the sliding portion 31b of the light shielding plate 31 in accordance with the rotation of the drive pin 53.

  The light shielding plate 34 is formed in a symmetrical shape with the light shielding plate 33. As shown in FIG. 5, reference numerals corresponding to the respective portions corresponding to the respective portions of the light shielding plate 33 are attached, and a detailed description thereof is given. Omitted.

  The drive mechanism 4 is rotated by meshing with a drive motor 41 and a flat gear 42 fixed to the rotation shaft of the drive motor 41 to support the face gear 43, the drive motor 41, and the face gear 43 that drive the aperture mechanism 3. The support member 44 is fixed to the base 2, and is constituted by a coil spring 47 or the like as urging means for reducing backlash between the face gear 43 and the flat gear 42 of the drive motor 41.

  As shown in FIGS. 1 and 4, the face gear 43 has an arc shape in which the gear portion 43 a is slightly larger than a semicircle, and a support shaft 45 erected perpendicularly to the horizontal portion 44 a of the support member 44. The teeth 43c are supported on the upper portion of the housing so as to be able to rotate while facing the horizontal portion 44a and to be slidable by at least a predetermined length in the axial direction. The support shaft 45 is fixed to the horizontal portion 44a so that the support shaft 44 is positioned directly below the center position of the base guide holes 2b, 2c, 2d, and 2e when the support member 44 is attached to the housing portion 2m of the base 2. Yes.

  As shown in FIGS. 1 and 4, the upper end surface (one side end surface) 43b of the gear portion 43a of the face gear 43 has a base of the base 2 at a predetermined position on the diameter passing through both ends of the substantially semicircular shape. Drive pins 51, 52, 53, 54 are erected corresponding to the base guide holes 2b, 2c, 2d, 2e. That is, the drive pins 51 and 52 and the drive pins 53 and 54 are arranged concentrically, the drive pins 51 and 52 are at predetermined positions on the same outer circumference, and the drive pins 53 and 54 are the same on the inner side. It is arranged at a predetermined position on the circumference.

  That is, the drive pins 51, 52, 53, 54 are erected on the diameter passing through the rotation center of the face gear 43, and appropriately change the radial distance from the rotation center of the face gear 43 as will be described later. By doing so, the sliding length in which the four light shielding plates 31 to 34 are slid and slid in the linear direction to adjust the opening of the diaphragm 38, that is, the light shielding amount of the light shielding plates 31 to 34 is adjusted optimally. It has become.

  These drive pins 51, 52, 53, 54 pass through the base guide holes 2 b, 2 c, 2 d, 2 e and protrude from the upper surface portion 2 a by a predetermined length, and in accordance with the rotation of the face gear 43, The arcuate base guide holes 2b, 2c, 2d, and 2e are slidable along the circumferential direction.

  The lower portion of the coil spring 47 is supported by a cylindrical portion 43 d concentrically provided at the opening end of the shaft hole of the upper end surface 43 b of the face gear 43, and the lower end is accommodated in the annular groove 43 e and attached to the face gear 43.

  A position detection sensor 48 is provided at a predetermined position on the upper surface of the horizontal portion 44 a of the support member 44 so as to face the predetermined teeth 43 c of the face gear 43. This position detection sensor 48 is an optical sensor, for example, and detects an initial position of an aperture mechanism 3 described later, for example, an aperture fully open position. The gear portion 43a of the face gear 43 is not limited to the substantially semicircular shape as described above, but may be a circular shape.

  The drive motor 41 is attached to the vertical portion 44b of the support member 44 so that the flat gear 42 attached to the shaft loosely penetrates the hole 44c of the vertical portion 44b of the support member 44 and meshes with the teeth 43c of the face gear 43. It is done. The drive motor 41 is a step motor, and its rotation is controlled by drive pulses supplied from a control circuit (not shown).

  When the diaphragm device 1 shown in FIG. 1 is assembled, first, the spur gear 42 of the drive motor 41 is allowed to pass through the hole 44c of the vertical portion 44b of the support member 44, and the drive motor 41 is fixed to the vertical portion 44b with screws 61. To do. Next, the face gear 43 in which the drive pins 51 to 54 are erected is attached to the support shaft 45 of the support member 44, and the teeth 43 c are engaged with the flat gear 42 of the drive motor 41. The lower part of the coil spring 47 is fitted on the cylindrical portion 43d and inserted into the annular groove 43e, and the lower end surface is brought into contact with the bottom surface of the annular groove 43e. A position detection sensor 48 is attached to a predetermined position on the upper surface of the horizontal portion 44 a of the support member 44 so as to face the teeth 43 c of the face gear 43.

  By using the face gear 43 as a gear that meshes with the flat gear 42 of the drive motor 41, when the flat gear 42 of the drive motor 41 is meshed with the face gear 43, the tolerance regarding the axial mounting position of the drive motor 41 is large. As a result, assembly becomes easy.

  Next, a support member 44 is attached to the housing portion 2m of the base 2, and the drive pins 51 to 54 corresponding to the base guide holes 2b to 2e of the base 2 are passed through to house the face gear 43 in the housing 2m. And fixed with screws 62. The drive pins 51 to 54 pass through the base guide holes 2b to 2e, and the tips protrude from the upper surface portion 2a.

  The coil spring 47 presses the teeth 43 c of the face gear 43 against the teeth of the flat gear 42 of the drive motor 41 with the upper end surface pressed against the lower surface of the base 2. Thereby, the backlash between the spur gear 42 and the face gear 43 is removed. A coil spring 47 is contracted between the lower surface of the base 2 and the face gear 43, and backlash between the flat gear 42 and the face gear 43 is removed. It is possible to save space.

  Next, the sliding portion 31b of the light shielding plate 31 is placed on the rails 2f and 2g of the upper surface portion 2a of the base 2, the tip of the driving pin 51 is passed through the pin hole 31h, and the driving pin 53 is loosened in the slit 31i. Make it stick out. Next, the sliding portion 33b of the light shielding plate 33 is placed on the sliding portion 31b, the tip of the drive pin 53 is passed through the pin hole 33h, and the light shielding plate guide holes 31f and 31g of the sliding portions 31b and 33b are inserted. The light shielding plate guide holes 33f and 33g are aligned. Next, the guide pin 11 is passed through the light shielding plate guide holes 33f and 31f and the guide pin 12 is passed through the light shielding plate guide holes 33g and 31g from above, and these guide pins 11 and 12 are press-fitted into the holes of the upper surface portion 2a. Fix it.

  As described above, the guide pin 11 has a head portion whose diameter is slightly larger than the groove width of the light shielding plate guide holes 31f and 31g, and a shaft portion whose shaft diameter is slidable in the light shielding plate guide holes 31f and 31g. And the length is slightly longer than the plate thickness of the sliding portions 31b and 33b placed on top of each other, and the press-fitting portion is fixed to the hole of the upper surface portion 2a.

  The guide pin 12 is the same as the guide pin 11. As a result, the light shielding plate 31 can slide on the rails 2f and 2g of the base 2 and the light shielding plate 33 on the sliding portion 31b of the light shielding plate 31 in a straight line along the longitudinal direction without departing. Is done.

  Similarly, the sliding portion 32b of the light shielding plate 32 is placed on the rails 2i and 2j of the upper surface portion 2a of the base 2, and the tip of the drive pin 52 is passed through the pin hole 32h. Next, as shown in FIG. 5, the sliding portion 34b of the light shielding plate 34 is placed on the sliding portion 32b, the tip of the drive pin 54 is passed through the pin hole 34h, and the light shielding plate guide of the sliding portions 32b and 34b is placed. The holes 32f and 32g and the light shielding plate guide holes 34f and 34g are aligned.

  Next, the guide pin 13 is passed through the light shielding plate guide holes 34f and 32f and the guide pin 14 is passed through the light shielding plate guide holes 34g and 32g from above, and these guide pins 13 and 14 are pressed into the holes of the upper surface portion 2a. Fix it.

  In this way, the light shielding plates 31 to 34 are attached on the upper surface portion 2 a of the base 2. The light shielding plate 31 is in sliding contact with the front surface of the light shielding plate 32, the light shielding plate 33 is in sliding contact with the front surface of the light shielding plate 31, and the light shielding plate 34 is in sliding contact with the rear surface of the light shielding plate 32. The light is not leaked.

  Next, the operation of the diaphragm device 1 will be described with reference to FIGS. In the present embodiment, the aperture device 1 uses the position where the aperture 38 is fully opened as the initial position. In the diaphragm 1, the face gear 43 is stopped at a position of 45 ° with respect to the longitudinal direction as shown in FIG. 4 at the initial position, and the drive pins 51 to 54 are mounted on the base 2 as shown in FIG. Of the base guide holes 2b to 2e.

  As shown in FIG. 6, the light shielding plates 31 and 32 are moved to the maximum position on the left and right, and the light shielding plates 33 and 34 have the end surfaces 33c and 34c moved to the maximum position on the left and right, and the end surfaces 33c and 34c are It comes to coincide with the end faces 31m and 32m of the diaphragm 38. The hexagonal diaphragm 38 formed by the trapezoidal cutouts 31e and 32e of the light shielding plates 31 and 32 is fully opened.

  When the drive motor 41 rotates and the face gear 43 shown in FIG. 4 rotates in the direction of the arrow CCW, the drive pins 51 and 53 move the light shielding plates 31 and 33 rightward in the drawing as shown in FIG. Further, the drive pins 52 and 54 slide the light shielding plates 32 and 34 in the direction approaching the left direction in the drawing. As the light shielding plates 31 and 32 move, the diaphragm 38 becomes smaller.

  Since the drive pins 51 and 52 are located outside the drive pins 53 and 54, the rotation speed is faster and the rotation distance is longer than those of the drive pins 53 and 54. When the face gear 43 rotates to the position shown in FIG. 7 and the drive pins 51 to 54 move to the center of the base guide holes 2b to 2e, the light shielding plates 31 to 34 slide greatly to the position shown in FIG. The shielding plates 33 and 34 on both sides slide slightly. Then, as shown in FIG. 9, the diaphragm 38 is half open.

  When the drive motor 41 further rotates to rotate the face gear 43, the drive pins 51 and 53 move the light shielding plates 31 and 33 to the right in the figure, and the drive pins 52 and 54 move the light shielding plates 32 and 34 to the right. Slide in the middle left direction.

  Then, when the face gear 43 rotates to the position shown in FIG. 10, the drive pins 51 to 54 move to the other end positions of the base guide holes 2b to 2e as shown in FIG. 11, and as shown in FIG. The diaphragm 38 is minimized, and the light shielding plates 33 and 34 move slightly together with the light shielding plates 31 and 32. Then, the drive motor 41 stops at the position.

  The end surfaces 33c, 34c of the light shielding plates 33, 34 on both sides overlap the end surfaces 31d, 32d of the light shielding plates 31, 32, and shield the outer sides of the light shielding plates 31, 32 from light. In this way, by appropriately changing the radial distance from the rotation center of the four drive pins 51 to 54 provided on the face gear 43, the four light shielding plates 31 to 34 are slid in the linear direction and slid. Thus, the sliding length for adjusting the opening of the diaphragm 38, that is, the light shielding amount of the light shielding plates 31 to 34, can be optimally adjusted.

  By using the two light shielding plates 33 and 34 on the outer side, the two light shielding plates 31 and 32 forming the diaphragm 38 can be compared with the case where only the two light shielding plates 31 and 32 forming the diaphragm 38 are used. The lateral width can be reduced, the lateral width of the entire diaphragm device can be reduced, and space saving can be achieved. When the diaphragm 38 is fully opened from the minimum, the drive motor 41 is rotated in the direction opposite to the above.

  Further, by using a step motor as the drive motor 41, it is possible to finely and easily adjust the aperture of the diaphragm 38 by controlling the number of drive pulses to be supplied.

  In the above-described embodiment, the light shielding plates 33 and 34 are not necessarily required, and only the light shielding plates 31 and 32 may be used. In this case, the light shielding plates 31 and 32 may be widened to shield the outer side. Further, by omitting the light shielding plates 33 and 34, the drive pins 53 and 54 and the base guide holes 2d and 2e of the base 2 become unnecessary, the number of processing is reduced, the number of parts is reduced, and the assembling property is reduced. Improvement is achieved.

  In the above-described embodiment, the flat gear 42 is used for the drive motor 41 and the face gear 43 is used as means for driving the drive pins 51 to 54. However, the present invention is not limited to this. Instead, for example, a bevel gear can be used.

  Further, the light shielding plate is not limited to the one that is erected with respect to the base 2 and slides and slides, but is provided horizontally along the base 2 so as to slide and slide. It may be. For example, in FIG. 1, the vertical portions (light-shielding portions) 31a, 32a, 33a, and 34a and the horizontal portions (sliding portions) 31b, 32b, 33b, and 34b of the light-shielding plates 31 to 34 having a substantially L-shape It is good also as flat form.

  The present invention is not limited to an aperture device such as a liquid crystal projector or a DMC projector, and can be implemented for aperture devices of various devices.

DESCRIPTION OF SYMBOLS 1 Diaphragm 2 Base 2a Upper surface part 2b-2e Base guide hole 2f-2k Rail 2m Storage part 3 Diaphragm mechanism 4 Drive mechanism 11, 12, 13, 14 Guide pin 31, 32, 33, 34 Light-shielding plate 31a, 32a , 33a, 34a Shading part (vertical part)
31b, 32b, 33b, 34b Sliding part (horizontal part)
31c, 31d, 32c, 32d, 33c, 34c End face 31e, 32e Notch 31h, 32h, 33h, 34h Pin hole 31i, 32i Slit 31f, 31g, 32f, 32g, 33f, 33g, 34f, 34g Light shielding plate guide hole 31m, 32m End face 38 Diaphragm 41 Drive motor 42 Flat gear 43 Face gear 43a Gear part 43b Upper end face 43c Teeth 43d Cylindrical part 43e Annular groove 44 Support member 44a Horizontal part 44b Vertical part 44c Hole 45 Support shaft 47 Coil spring (biasing means)
48 Position detection sensors 51, 52, 53, 54 Drive pins 61, 62 Screws

Claims (8)

  It consists of a base (2) and two first light shielding plates (31, 32) slidable facing each other along the base (2) and the two first light shielding plates (31). , 32) are provided with notches (31e, 32e) which cooperate with the opposing end faces (31c, 32c) to form a diaphragm (38), and are adjacent to the two first light shielding plates (31, 32) or A diaphragm mechanism (3) in which the diaphragm (38) is adjusted according to sliding in the direction of separating, a drive motor (41) attached to the base (2) via a support plate (44), A face gear that is rotatably supported by a support shaft (45) that is erected on the support plate (44) and that rotates in mesh with a spur gear (42) attached to the drive motor (41). (43), and the face gear (43) when erected at a predetermined position on one end face (43b). The two first light shielding plates (31, 32) are engaged with the first pin holes (31h, 32h), respectively, and the two gears are rotated according to the rotation of the face gear (43). Two first drive pins (51, 52) that bring the first light shielding plates (31, 32) close to or away from each other, and are contracted between the base (2) and the face gear (43). And a drive mechanism (4) comprising urging means (47) for pressing the face gear (43) against the spur gear (42).   The two first drive pins (51, 52) are arranged on a straight line passing through the rotation center of the face gear (43) and symmetrically with respect to the rotation center. The diaphragm device according to claim 1.   The base (2) is formed with two arc-shaped first base guide holes (2b, 2c) through which the two first drive pins (51, 52) are pivoted. The diaphragm device according to claim 1, wherein the diaphragm device is provided.   The first light-shielding plate (31, 32) is provided with two first light-shielding plate guide holes (31f, 31g, 32f, 32g) parallel to the sliding direction, and the base (2). The base (2) is guided by two guide pins (11, 12, 13, 14) that are fixed and slidably penetrate the light shielding plate guide holes (31f, 31g, 32f, 32g). 4. The diaphragm device according to claim 1, wherein the diaphragm device is slid linearly along the line.   The aperture mechanism (3) is arranged on the outer side of the two first light shielding plates (31, 32) and along the base (2) together with the first light shielding plates (31, 32). And further includes two second light shielding plates (33, 34) that shield the outer sides of the first light shielding plates (31, 32), and the drive mechanism (4) includes the face. Engage with the second pin holes (33h, 34h) provided on the second light shielding plates (33, 34), respectively, standing at a predetermined position on one end face (43b) of the gear (43). In response to the rotation of the face gear (43), the second light shielding plate (31, 32) and the two second light shielding plates (33, 34) are moved closer to or away from each other. 53. The diaphragm device according to any one of claims 1 to 4, further comprising 53, 54).   The second drive pin (53, 54) is arranged on a straight line passing through the rotation center of the face gear (43) and at a symmetrical position with respect to the rotation center. 5. The aperture device according to 5.   The base (2) is further formed with two arc-shaped second base guide holes (2d, 2e) through which the two second drive pins (53, 54) are pivoted. The diaphragm device according to claim 5 or 6, wherein the diaphragm device is provided.   The second light shielding plates (33, 34) are arranged in parallel with the second light shielding plate guide holes (33f) along the first light shielding plate guide holes (31f, 31g, 32f, 32g) along the sliding direction. , 33g, 34f, 34g), guide pins fixed to the base (2) and slidably passing through the second light shielding plate guide holes (33f, 33g, 34f, 34g) ( 11, 12, 13, 14) and is slid linearly along the base (2) together with the first light shielding plate (31, 32). 8. The aperture device according to any one of 7 above.

Images