JP5117314B2 - Projector aperture device - Google Patents

Description

  The present invention relates to a diaphragm device for controlling the light amount of a light source of a projector that projects an image or a character on a transmissive or reflective screen.

  Recently, projectors equipped with liquid crystal panels, DMDs (digital micromirror devices), etc. have appeared and are used for various presentations and sales presentations as well as equipment for rear projection TVs. And as this kind of projector, in order to change the illumination light quantity from the light source lamp corresponding to the brightness of the room to project, or to temporarily weaken the illumination light when nothing is projected, The following patent does not change the amount of light emitted from the light source lamp itself, but controls the light amount of the light source light by changing the optical path area of the light source light by an aperture device arranged in the vicinity of the light source lamp. It is described in Document 1.

  Especially in a liquid crystal projector, when nothing is projected, if the illumination light is temporarily reduced by the diaphragm device, the deterioration of the liquid crystal panel can be prevented, which is advantageous in terms of durability. It has been known. Japanese Patent Application Laid-Open No. H10-228561 describes that it is possible to obtain a high-contrast image by providing such a diaphragm device and changing the light amount of the light source light. Furthermore, even in the case of an overhead projector using a variable magnification optical system as a projection optical system, it is possible to obtain a projection image at a high magnification by arranging an aperture device between a stage for placing a document and a light source. Is described in Patent Document 2 below. The present invention can be used for these various projectors, and particularly relates to an aperture device effective for use in a projector using a liquid crystal panel or the like in order to obtain a high contrast ratio.

JP 2004-69966 A JP-A-8-227102

  In the above-mentioned Patent Document 1, two diaphragm members (the light shielding plate in Patent Document 1) are rotated within a predetermined rotation angle range in opposite directions such as a double door, and pass between them. A projector diaphragm device (light control device) is disclosed in which the amount of light is changed by changing the optical path area. As an example of a specific configuration for doing so, there is described a configuration in which two throttle members are directly attached to the rotating shafts of the rotors of two stepping motors.

  By the way, as described above, in a projector that enlarges and projects an image displayed on a liquid crystal panel or the like onto a screen, in order to always obtain a projected image with a desired contrast, the image conditions displayed on the liquid crystal panel or the like In response to this change, the amount of light needs to be changed by the diaphragm device on the optical path of the light source light during projection, and such a change in the amount of light is required to have good responsiveness. That is, it is required to quickly operate the diaphragm member in response to changes in image conditions displayed on a liquid crystal panel or the like.

  However, in the case of the above-described configuration described in Patent Document 1, since the two throttle members are directly attached to the rotation shafts of the rotors of the two stepping motors, in order to rotate the throttle members quickly. To achieve this, the rotational speed of the rotor must be increased. However, when doing so, the stepping motor becomes large and the unit price becomes high. In addition, if the throttle member is rotated via the speed increasing gear mechanism, a relatively loud sound is generated, and if it is attempted to ensure sound insulation and silence, the cost increases. .

  The present invention has been made to solve such problems, and the object of the present invention is to provide two actuators that are arranged so that the rotation axes of the rotor are parallel to each other. Two diaphragm members are rotated in opposite directions faster than the rotor on each axis parallel to the rotation axis so that the optical path area of the light source light can be changed. Another object of the present invention is to provide a projector diaphragm device that can be manufactured at low cost.

  In order to achieve the above object, a projector diaphragm device of the present invention has a plate-like portion having both a first surface and a second surface, and the first surface is on the optical path side of the light source light. In this way, the rotation axis of each rotor is perpendicular to the second surface at both sides of the base disposed in the projector and the closest line parallel to the optical axis of the light source light on the second surface. In this way, the first electromagnetic actuator, which is attached to the plate-like portion and is reciprocated within a predetermined angle range around each rotation shaft, projects perpendicularly to the first surface side, and the first electromagnetic actuator. Two electromagnetic actuators, and the first surface side at a predetermined position between a position on the first surface side corresponding to the rotation axis of the first electromagnetic actuator and an operation locus of the output pin of the first electromagnetic actuator. The first shaft upright and the front A first erected on the first surface side at a predetermined position between the position on the first surface side corresponding to the rotation axis of the second electromagnetic actuator and the operation locus of the output pin of the second electromagnetic actuator. Two shafts, a first light-shielding plate portion that partially shields the optical path, and a first attachment piece that is formed substantially perpendicular to the first light-shielding plate portion and is rotatably attached to the first shaft The first mounting piece has a long hole on the first light shielding plate side of the mounting portion with respect to the first shaft, and the output pin of the first electromagnetic actuator is fitted into the long hole. A first diaphragm member, a second light shielding plate portion that partially shields the optical path, and a substantially right angle with respect to the second light shielding plate portion, and is rotatably attached to the second shaft. And the second mounting piece is a mounting portion for the second shaft. And a second aperture member having a long hole on the second light-shielding plate portion side and fitting the output pin of the second electromagnetic actuator into the long hole. The members are rotated in opposite directions by simultaneously rotating the rotors of the two electromagnetic actuators in opposite directions.

  In that case, the two diaphragm members are formed such that the shortest linear dimension from the mounting portions of the mounting pieces to the virtual surface extending the light shielding plate portions is substantially the same. The two electromagnetic actuators are configured such that each of the rotation axes is relatively displaced in the length direction of the line on both sides of the closest line parallel to the optical axis on the second surface. If it is made to attach to a plate-shaped part, when two aperture members rotate relatively in the direction which closes an optical path, aperture plates will not collide.

  In addition, the plate-like portion is provided with a stopper on the first surface with which the mounting pieces abut when the two diaphragm plates are relatively rotated in the direction of closing the optical path. Each of the two diaphragm members has a diaphragm opening forming edge, and when the diaphragm member is stopped in contact with the stopper, the diaphragm opening forming edge forms a minimum diaphragm opening centered on the optical axis. It may be.

  Further, the base has a second plate-like portion on the opposite side of the plate-like portion with the optical path in between, and the first plate is disposed on the surface of the second plate-like portion on the optical path side. A third shaft is erected so as to face the shaft, and a fourth shaft is erected so as to face the second shaft, and the first diaphragm member includes the first light shielding plate portion. And a third mounting piece formed so as to be symmetric with the first mounting piece, the third mounting piece being rotatably attached to the third shaft, and The two diaphragm members have a fourth mounting piece formed on the opposite side of the second light shielding plate portion so as to be symmetric with the second mounting piece, and the fourth mounting piece is used as the fourth shaft. If it is attached so as to be able to rotate, a robust and durable projector diaphragm can be obtained.

  According to the present invention, the two diaphragm members are rotated in the opposite direction by two actuators arranged so that the rotation axes of the rotor are parallel to each other, so that the optical path area of the light source light is changed. In the projector diaphragm device, the diaphragm member is rotated by the output pin provided at the radial position of the rotation shaft of the rotor, and the position of the rotation shaft of the diaphragm member is set as the rotation center position of the rotor. Since it is in a predetermined position between the operation locus of the output pin, it is possible to rotate the diaphragm member faster than the rotor and to have a highly responsive projector diaphragm apparatus with a simple and low-cost configuration. It becomes possible to obtain.

  The best mode for carrying out the present invention will be described with reference to the illustrated embodiments. FIG. 1 is a perspective view showing the control state of the minimum optical path as viewed from the light source side. FIG. 2 is a front view showing the control state of the minimum optical path as viewed from the light source side, and FIG. 3 is a front view showing the control state of the maximum optical path in the same manner as FIG. 4 is a cross-sectional view taken along line AA in FIG. 2 and viewed in the direction of the arrow, and FIG. 5 is a cross-sectional view taken along line BB in FIG. 3 and viewed in the direction of the arrow. 6 is a partially enlarged view of FIG. 5, and FIG. 7 is a cross-sectional view of FIG. 6 taken along the line CC and viewed in the direction of the arrow. Further, FIG. 8 is for explaining the configuration of the actuator used in the embodiment, and FIG. 8A is a diagram showing only the actuator in the state shown in FIG. 8 (b) is a bottom view of FIG. 8 (a), and FIG. 8 (c) is a cross-sectional view taken along the line DD of FIG. 8 (b) and viewed in the arrow direction.

  First, the configuration of this embodiment will be described. As shown in FIG. 1, the base of the diaphragm unit is composed of a first frame member 1 and a second frame member 2 which are all made of metal. Among them, the first frame member 1 has three plate-like portions 1a, 1b, and 1c, and has a U-shape as a whole, and its specifics can be obtained by comparing FIG. 1 and FIG. As can be seen, a bent piece 1d and a protruding piece 1e are formed at the tip of the plate-like portion 1a, and a threaded hole 1f is formed through the bent piece 1d. In addition, the tip of the plate-like part 1c facing the plate-like part 1a has a notch-like shape formed in a U-shape by one long side edge and two short side edges on both sides thereof. A recess 1g (see FIG. 1) is formed, and a hole 1h (see FIG. 2) is formed in the vicinity thereof.

  On the other hand, the second frame member 2 has a flat plate shape as a whole and is opposed to the plate-like portion 1b, and has two positioning holes 2a and 2b necessary for attachment to the projector body and two penetrating holes. Screw holes 2c and 2d are provided. 1 and 2, a hole 2e for inserting the protruding piece 1e and a long hole 2f for aligning with the screw hole 1f are formed in the vicinity of the lower end of the second frame member 2. doing. Among them, the hole 2e has a shape close to a rectangle, and the dimension in the length direction is substantially the same as the width of the protruding piece 1e. However, the dimension in the direction perpendicular to the protruding piece 1e is the same as that of the protruding piece 1e. It is considerably larger than the thickness dimension. And the receiving part 2e-1 is formed in the upper edge. The long hole 2f is formed long in the length direction of the second frame member 2, and the dimension in the width direction is substantially the same as the diameter of the screw hole 1f.

  Further, the upper end portion of the second frame member 2 is formed with a protruding piece 2g to be engaged with the concave portion 1g and two bent pieces on both sides thereof, but in FIG. 1 and FIG. Of these two bent pieces, only the bent piece 2h on the light source side is clearly shown. The width dimension of the protruding piece 2g is substantially the same as the length of the edge of the long side of the U-shaped recess 1g, and fits without rattling. In addition, as can be seen from FIG. 2, the bent piece 2h is formed with a threaded hole 2i that passes therethrough, and can be aligned with the hole 1h formed in the plate-like portion 1c. The diameters of the hole 1h and the screw hole 2i are substantially the same.

  Next, how to attach the first frame member 1 and the second frame member 2 to each other will be described. As is well known, in the case of a part made of a relatively thin plate material such as the first frame member 1 and having a plurality of bent portions, the present embodiment is implemented even if it is made of a synthetic resin. Even if it is made of metal as in the example, it is difficult to always maintain a predetermined shape at the part stage as in the case of ceramic. That is, depending on how the first frame member 1 is held, the dimension from the tip of the plate-like portion 1a (the right end in FIG. 2) to the protruding piece 1e at the tip of the plate-like portion 1c changes. Therefore, if no measures are taken, the first frame member 1 and the second frame member 2 can be obtained as a right-angled parallelogram by the three plate-like portions 1a, 1b, 1c and the second frame member 2. As a result, it becomes difficult to assemble, and as a result, there is a possibility that the later-described two throttle members 16 and 17 attached to the plate-like portions 1a and 1c cannot be smoothly rotated.

  Therefore, in the present embodiment, when the first frame member 1 and the second frame member 2 are assembled to each other, the above-mentioned right-angled parallelogram is easily devised without using excessive nerves. . First, in the present embodiment, the flat surface of the second frame member 2 has a dimension from the position corresponding to the upper surface of the two bent pieces (one is 2h) to the edge of the receiving portion 2e-1 of the hole 2e. The length dimension of the inner surface of the plate-like part 1b facing each other, that is, the design standard dimension from the inner surface of the plate-like part 1a to the inner surface of the plate-like part 1c is the same.

  Therefore, when assembling both, first, the hole 1h formed in the plate-like portion 1c of the first frame member 1 and the screw hole 2i formed in the bent piece 2h of the second frame member 2 are positioned. The screws 3 are inserted and screwed in from the hole 1h side. Next, the protruding piece 1 e formed in the plate-like portion 1 a of the first frame member 1 is inserted into the hole 2 e formed in the second frame member 2. At this time, when the protruding piece 1e is inserted so as to extend between the tips of the plate-like portion 1c, a contact state between the protruding piece 1e and the receiving portion 2e-1 may be obtained. Specifically, the contact state between the protruding piece 1e and the receiving portion 2e-1 cannot be obtained with certainty.

  Therefore, in such an inserted state, the second frame member 2 is lowered downward with respect to the bent piece 1d while maintaining the contact between the bent piece 1d of the first frame member 1 and the second frame member 2. To do. In other words, conversely, the bent piece 1 d is raised upward with respect to the second frame member 2. Then, after ensuring that the contact between the protruding piece 1e and the receiving portion 2e-1 is obtained, the screw 4 is inserted from the long hole 2f side and screwed into the screw hole 1f, whereby the mutual assembling work is performed. finish. Thus, in the present embodiment, the first frame member 1 and the second frame member 2 can be easily assembled with each other in a desired state. In the projector, the optical path of the light source light is formed from the near side of FIG. 2 toward the back through the space region at the substantially center of the base body configured as described above. Therefore, in FIGS. 2 and 3, the center of the optical path, that is, the optical axis position is marked with +.

  Next, various members attached to the base body configured as described above and the attachment configuration thereof will be described. First, as shown in FIGS. 4 and 5, on the inner surface of the plate-like portion 1 a, that is, the surface on the optical path side of the light source light, a position corresponding to the center of the optical path indicated by the alternate long and short dash line, Three stoppers 5, 6, and 7 are attached to positions on both sides. Further, as can be seen by comparing FIG. 4 and FIG. 5, the plate-like portion 1a is formed with two elongated holes 1i, 1j having a circular arc shape as a through hole over a predetermined angular range.

  Two shaft members 8 and 9 are erected on the inner surface of the plate-like portion 1a, but the mounting configuration is completely the same. Therefore, the specific configuration will be described in the case of the shaft member 9 shown in FIG. The shaft member 9 has a flange portion 9a at the tip, and a screw hole 9b is formed at the other end on the root side. The shaft member 9 has a small diameter portion 9c formed at the other end fitted in a hole 1k formed in the plate-like portion 1a, and a screw 10 is inserted from the outside of the plate-like portion 1a. It is attached to the plate-like portion 1a by being screwed to 9b. 2 and 3 show the screw 11 to which the shaft member 8 is attached in the same manner. Further, as shown in FIGS. 2 and 3, two shaft members 12, 13 are formed on the inner surface of the plate-like portion 1c in the same manner as the shaft members 8, 9, with screws 14, 15 is erected. Among them, the shaft member 12 is erected at a position facing the shaft member 8, and the shaft member 13 is erected at a position facing the shaft member 9.

  Next, the diaphragm member 16 rotatably attached to the shaft member 8 and the shaft member 12 and the diaphragm member 17 rotatably attached to the shaft member 9 and the shaft member 13 In the present embodiment, both are made of metal and the shape is exactly the same. Also, as will be described later, the mounting configuration is exactly the same except that the vertical positions are reversed. First, the shape of the throttle member 17 and how to attach it will be described mainly with reference to FIGS. 1, 6, and 7.

  As shown in FIG. 1, the diaphragm member 17 is symmetrical to each other so that the light shielding plate portion 17 a is long in the vertical direction and the upper and lower portions are parallel to the surface of the light shielding plate portion 17 a. The support pieces 17b and 17c formed in a shape, and mounting pieces 17d and 17e formed in symmetrical shapes by being bent from the support pieces 17b and 17c so as to be substantially perpendicular to the surface of the light shielding plate portion 17a. Have. The light shielding plate portion 17a is formed with a stepped aperture opening forming edge 17a-1. In this embodiment, the aperture opening forming edge 17a-1 is formed in a step shape on the light shielding plate portion 17a. However, the present invention is not limited to such a shape. The plate portion 17a may be a simple rectangle. Further, the support pieces 17b and 17c may be formed so as to be flush with the light shielding plate portion 17a, or the support pieces 17b and 17c are not formed, and the attachment pieces 17d and 17e are directly formed on the light shielding plate portion 17a. You may make it form from.

  As shown in FIG. 6, the attachment piece 17e is formed with two elongated holes 17f and 17g having the same shape and two circular holes 17h and 17i having different sizes. Although not shown, the other mounting piece 17d has a plane shape symmetrical to that of the mounting piece 17e, and is a long hole of the same shape at a position facing the long holes 17f and 17g of the mounting piece 17e. Are formed, and holes of the same shape are formed at the positions facing the circular holes 17h and 17i of the mounting piece 17e.

  The hole 17h formed in the throttle member 17 is a hole necessary for rotatably attaching the throttle member 17 to the shaft member 9. Therefore, in the present invention, the diameter of the hole 17h may be slightly reduced so that the hole is directly fitted to the shaft member 9. However, in the case of the present embodiment, the intermediate member 18 made of synthetic resin is integrally attached to the diaphragm member 17, and the intermediate member 18 is attached to the shaft member 9. That is, as can be seen from FIGS. 6 and 7, the mediating member 18 includes two long holes 18a and 18b that are slightly smaller than the long holes 17f and 17g, a cylindrical portion 18c, a pin 18d, and a hook portion 18e. And the cylindrical portion 18c is rotatably fitted to the shaft member 9. The throttle member 17 is engaged with the cylindrical portion 18c in the hole 17h, press-fitted with a pin 18d in the hole 17i, and is latched by the hook portion 18e. Thereby, the center positions of the long hole 17f and the long hole 18a, and the long hole 17g and the long hole 18b are made to coincide.

  The other attachment piece 17d of the diaphragm member 17 is also attached to the shaft member 13 with the same configuration. Therefore, in FIG.2 and FIG.3, although the mediation member 19 used for the attachment is shown, the code | symbol of a site | part is abbreviate | omitted. Further, as described above, the configuration of the mounting piece 17e and the mediating member 18 and their mounting configuration with respect to the shaft member 9 have been described in detail with reference to FIG. 6 and FIG. Only representative parts are labeled.

  On the other hand, the other diaphragm member 16 has the same shape as the diaphragm member 17 as described above, and the vertical direction is reversed without changing the direction. 12 is attached. That is, the diaphragm member 16 and the diaphragm member 17 are common parts. Therefore, similarly to the diaphragm member 17, the diaphragm member 16 includes a light shielding plate portion 16a, support pieces 16b and 16c, and attachment pieces 16d and 16e. A stepped aperture opening forming edge 16a-1 is formed in the light shielding plate portion 16a.

  4 and 5 show the shape of the mounting piece 16e. As described above, the diaphragm member 16 is the same as the diaphragm member 17 in the vertical direction without changing the orientation. Therefore, the mounting piece 17e is shown in a symmetrical shape. Further, the mediating member 20 integral with the throttle member 16 has the same shape as the mediating member 18 described above. Further, the mutual integrated configuration of the throttle member 16 and the mediating member 20 and the mounting configuration thereof with respect to the shaft member 8 are substantially the same as those described with reference to FIGS. Therefore, in FIGS. 4 and 5, only the two long holes 20 a and 20 b formed in the mediating member 20 are labeled as in the case of the mediating member 18. Further, the other mounting piece 16d of the diaphragm member 16 is also attached to the shaft member 12 with the same configuration. Therefore, FIGS. 2 and 3 show the intermediate member 21 used for the attachment.

  Next, the structure of the two electromagnetic actuators AC1 and AC2 for reciprocatingly rotating the diaphragm members 16 and 17 and the structure for attaching the first frame member 1 to the plate-like portion 1a will be described. First, four columns of the same length are erected by caulking on the outer surface of the plate-like portion 1a, that is, the surface opposite to the optical path of the light source light. The two pillars 22 and 23 are clearly shown. A printed wiring board 24 is attached to the ends of these columns, and the two electromagnetic actuators AC1 and AC2 are individually connected to the plate-like part 1a between the printed wiring board 24 and the plate-like part 1a. Is attached. Further, these electromagnetic actuators AC1 and AC2 are common parts as electromagnetic actuators, and the mounting configuration with respect to the plate-like portion 1a is exactly the same. Therefore, in the following, the configuration of the electromagnetic actuator AC2 will be described mainly using FIG.

  FIG. 8A shows the electromagnetic actuator AC2 as seen from a slightly different angular position from the state shown in FIG. 8B is a bottom view of FIG. 8A, and FIG. 8C is a cross-sectional view taken along the line DD of FIG. 8B and viewed in the direction of the arrow. First, the rotor 25 shown in FIG. 8C includes a cylindrical permanent magnet 25a, a rotary shaft 25b integrally formed with the permanent magnet 25a with a synthetic resin material, and an output pin 25c. ing.

  The stator mainly includes a first stator frame 26, a second stator frame 27, a coil 28, and a yoke 29. Among them, the first stator frame 26 has a shape like a flowerpot that covers one cylindrical open end as a whole, and the second stator frame 27 has a plate shape as a whole. ing. In addition, the first stator frame 26 and the second stator frame 27 are in a state in which the output pin 25c of the rotor 25 is passed through an arc-shaped long hole 27a formed in the second stator frame 27. Thus, the rotating shaft 25b is supported, and the coil 28 is wound so as to surround the bearing portions. Thereafter, a cylindrical yoke 29 is fitted into the first stator frame 26.

  Since the coil 28 is composed of two coils, the first stator frame 26 is provided with four terminal pins 26a for attaching the coils, and the Hall element 30 is provided. A concave groove 26b for attaching the printed wiring board 31 provided therein is formed. And the terminal pin 26a and the printed wiring board 31 are attached to said printed wiring board 24 in the attachment state to the plate-shaped part 1a. Further, in this type of electromagnetic actuator, when the coil 28 is not energized, the stop position of the rotor 25 becomes extremely unstable. Therefore, four magnetic rods 32 for stabilizing the stop position by the magnetic force acting between the permanent magnets 25a are mounted in the four slots 26c of the first stator frame 26.

  As is well known, this electromagnetic actuator AC2 is a current control type actuator, and when one coil included in the coil 28 is energized, the rotor 25 is rotated to one side, and the other coil is energized. The rotor 25 is rotated to the other side. Then, the rotor 25 is stopped at a position where the rotational forces of both are balanced. Further, the rotational position of the rotor 25 is always detected by the Hall element 30, and the current value for the two coils is controlled by the detection signal to rotate the rotor 25 in a predetermined direction or at a predetermined position. It is supposed to be stopped.

  Next, the attachment structure with respect to the plate-shaped part 1a is demonstrated. As shown in FIG. 8B, the second stator frame 27 is formed with two mounting holes 27b. Further, as shown in FIG. 8A, two positioning pins 27c are formed on the surface on the plate-like portion 1a side. Therefore, the two positioning pins 27c are inserted into positioning holes (not shown) formed in the plate-like portion 1a, and two screws (not shown) are inserted into the two mounting holes 27b. It is screwed into a formed screw hole (not shown). In the attached state, as shown in FIGS. 6 and 7, the output pin 25 c penetrates the long hole 1 j of the plate-like portion 1 a, the long hole 18 a of the mediating member 18, and the throttle member 17. The long hole 17f is inserted into the long hole 18a and comes into contact with the edge of the long hole 18a.

  On the other hand, the other electromagnetic actuator AC1 has the same configuration and is attached to the plate-like portion 1a in the same manner. Therefore, FIGS. 4 and 5 illustrate the rotor 33, the rotation shaft 33a, and the output pin 33b of the electromagnetic actuator AC1, and FIGS. 2 and 3 illustrate the output pin 33b. . 4 and 5, the output pin 33b of the electromagnetic actuator AC1 also penetrates the long hole 1i of the plate-like portion 1a, and the long hole 20a of the mediating member 20 and the throttle member 16 It is inserted into a long hole (no symbol) and comes into contact with the edge of the long hole 20a.

  Therefore, the relationship between the mounting positions of the two electromagnetic actuators AC1 and AC2 with respect to the plate-like portion 1a and the standing positions of the two shaft members 8 and 9 will be described with reference to FIGS. First, the two electromagnetic actuators AC1 and AC2 have their rotation axes 33a and 25b on both sides of the closest line parallel to the optical axis (dashed line) on the outer surface of the plate-like portion 1a. Although they are equidistant from each other, they are attached so as to be arranged at positions relatively displaced with respect to the length direction of the line.

  On the other hand, the two shaft members 8 and 9 have an operation locus drawn by the rotation shafts 33a and 25b of the electromagnetic actuators AC1 and AC2 and the output pins 33b and 25c within a predetermined angle range (usually around 60 degrees at maximum from the production). Is erected on the inner surface of the plate-like portion 1a at a predetermined position. 4 and 5, the position of the rotation shaft 33 a and the position and interval of the shaft member 8 are the same as the interval between the position of the rotation shaft 25 b and the position of the shaft member 9. These shaft members 8 and 9 are equidistant from the line on both sides of the line parallel to the optical axis on the inner surface of the plate-like portion 1a, but with respect to the length direction of the line. Are attached so as to be arranged at relatively shifted positions.

  Further, as described above, the electromagnetic actuators AC1 and AC2 have the same configuration, and the diaphragm members 16 and 17 and the mediating members 20 and 18 are also members having the same shape. Therefore, the interval between the shaft member 8 and the output pin 33b is also the same as the interval between the shaft member 9 and the output pin 25c. In the case of the present embodiment, the two electromagnetic actuators AC1 and AC2 are configured such that the rotors 33 and 25 are rotated in opposite directions synchronously.

  Next, the operation of this embodiment will be described mainly with reference to FIGS. 2 to 5 in the case where the operation of this embodiment is adopted in a liquid crystal projector. 2 and 4 show the control state of the minimum optical path in which the two diaphragm members 16 and 17 enter the optical path and the light amount of the light source is limited to the maximum, that is, the control state of the minimum aperture opening. The throttle members 16 and 17 are in contact with the stopper 5. At this time, the coils of the two electromagnetic actuators AC1 and AC2 are energized, and in FIG. 4, the rotor 33 may be rotated counterclockwise and the rotor 25 may be rotated clockwise. As is well known, the electromagnetic actuators AC1 and AC2 in the example are maintained in the stopped state due to the presence of the magnetic rod 32 described with reference to FIG. 8, as is well known.

  Further, as described above, the relative positions of the two shaft members 8 and 9 are shifted along the line parallel to the optical axis on the surface of the plate-like portion 1a. The light shielding plate portions 16a and 17a of the members 16 and 17 overlap each other in the upper and lower regions of FIG. 2 without colliding with each other, and thereby, the stepped aperture opening forming edges 16a-1 and 17a-1 are overlapped. At the center, a minimum optical path centered on the optical axis can be formed.

  In the present embodiment, in this way, the optical path with the minimum opening centered on the optical axis can be formed at the center of the stepped aperture opening forming edges 16a-1 and 17a-1. The present invention is not limited to the above configuration. That is, the aperture openings forming edges 16a-1 and 17a-1 may not be stepped, but may be shaped so as to obtain a substantially rectangular minimum opening, or a shape capable of obtaining a substantially oval minimum opening. Alternatively, the two aperture opening forming edges 16a-1 and 17a-1 may be formed in parallel straight lines so as to form an elongated optical path in the vertical direction. However, in terms of the configuration of the lens, it is preferable to make the lens shape as close to a circle as possible with the optical axis as the center, as in this embodiment.

  Further, when the aperture opening forming edges 16a-1 and 17a-1 are formed in a straight line so as to form an elongated optical path, the relative positions of the two rotary shafts 33 and 25, as shown in FIG. It is not necessary to configure the relative positions of the two shaft members 8 and 9 to be shifted along a line parallel to the optical axis on the surface of the plate-like portion 1a. Further, as in this embodiment, the relative positions of the two rotating shafts 33 and 25 and the relative positions of the two shaft members 8 and 9 are along a line parallel to the optical axis on the surface of the plate-like portion 1a. When configured so as to be shifted, the two diaphragm members 16 and 17 are not brought into contact with the stopper 5 in the minimum optical path control state, but are in contact with the stopper 5 in a state where the optical path is completely shielded as in the present embodiment. You may make it contact. By doing so, it is possible to prevent deterioration of the liquid crystal panel even if the light source is turned on when not projecting.

  When the optical path is increased from the state shown in FIGS. 4 and 5, the rotor 33 is simultaneously rotated clockwise and the rotor 25 is counterclockwise. Thereby, the aperture member 16 is rotated clockwise by the output pin 33b, and the aperture member 17 is rotated counterclockwise by the output pin 25c. For this reason, the two diaphragm members 16 and 17 increase the optical path formed by the opening restricting edges 16a-1 and 17a-1 of both, and are stopped at a position where an image on the screen can obtain a predetermined contrast. .

  Then, in response to changes in image conditions displayed on the liquid crystal panel, when the contrast of the image on the screen changes during projection, the optical path is increased or decreased accordingly. Become. Therefore, the operation of the throttle members 16 and 17 is required to be quick, but the present embodiment is configured to sufficiently meet such a requirement. This is because the shaft members 8 and 9 that are the rotation shafts of the throttle members 16 and 17 exist between the operation shafts of the rotation shafts 33a and 25b and the output pins 33b and 25c. This is because it can be rotated at an angle larger than the rotation angle.

  Further, such rotation / stop operation of the throttle members 16 and 17 may be frequently performed, so that durability and quietness are required. In this regard, in the case of the present embodiment, since the diaphragm members 16 and 17 are made of metal and the output pins 33b and 25c are made of synthetic resin, the output pins 33b and 25c are worn, and durability and quietness are achieved. May cause problems. Therefore, in the case of the present embodiment, such concerns are resolved by interposing the mediating members 20 and 18. However, if it is not necessary to deal with the occurrence of such a problem, the throttle members 16 and 17 may be directly attached to the shaft members 8 and 9 without providing the mediating members 20 and 18.

  FIGS. 3 and 5 show the control state of the maximum optical path in such a manner that the two diaphragm members 16 and 17 are brought into contact with the stoppers 6 and 7 and stopped.

  The electromagnetic actuators AC1 and AC2 of the present embodiment are current control type electromagnetic actuators as described with reference to FIG. 8, but the electromagnetic actuator of the present invention is not limited to such a configuration, A step motor may be used. In addition, in the current control type electromagnetic actuator, the coil 28 is not two coils as in the present embodiment, but only one, and the rotational position of the rotor 25 is controlled by the Hall element 30 as in the present embodiment. It is also well known that the current value is controlled while detecting and the rotor 25 is stopped at a predetermined position. Therefore, the electromagnetic actuator of the present invention may have such a configuration. Further, the diaphragm members 16 and 17 of the present embodiment are common parts, but the present invention is not limited to this. Therefore, the diaphragm member of the present invention may be configured without the support pieces 16b and 17b and the attachment pieces 16d and 17d shown in FIGS.

It is the perspective view of the Example which showed the control state of the minimum optical path seeing from the light source side. It is the front view of the Example which showed the control state of the minimum optical path seeing from the light source side. It is the front view of the Example which showed the control state of the maximum optical path seeing from the light source side. It is sectional drawing which cut | disconnected FIG. 2 by the AA line and looked at the arrow direction. It is sectional drawing which cut | disconnected FIG. 3 by the BB line and looked at the arrow direction. It is the elements on larger scale of FIG. It is sectional drawing which cut | disconnected FIG. 6 by CC line and looked at the arrow direction. FIG. 8A is a diagram showing only the actuator in the state shown in FIG. 3, and FIG. 8B is a diagram for explaining the configuration of the actuator used in the embodiment. FIG. 8A is a bottom view of FIG. 8A, and FIG. 8C is a cross-sectional view taken along the line DD of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st frame member 1a, 1b, 1c Plate-shaped part 1d, 2h Bending piece 1e, 2g Protruding piece 1f, 2c, 2d, 2i, 9b Screw hole 1g Recessed part 1h, 1k, 2e, 17h, 17i Hole 1i, 1j , 2f, 17f, 17g, 18a, 18b, 20a, 20b, 27a Long hole 2 Second frame member 2a, 2b Positioning hole 2e-1 Receiving part 3, 4, 10, 11, 14, 15 Screw 5, 6, 7 Stopper 8, 9, 12, 13 Shaft member 9a Flange portion 9c Small diameter portion 16, 17 Diaphragm member 16a, 17a Light shielding plate portion 16a-1, 17a-1 Diaphragm opening forming edge 16b, 16c, 17b, 17c Support piece 16d, 16e , 17d, 17e Mounting piece 18, 19, 20, 21 Intermediary member 18c Tube portion 18d Pin 18e Hook portion AC1, AC2 Electromagnetic actuator 22, 23 24, 31 Printed wiring board 25, 33 Rotor 25a Permanent magnet 25b, 33a Rotating shaft 25c, 33b Output pin 26 First stator frame 26a Terminal pin 26b Concave groove 26c Groove hole 27 Second stator frame 27b Mounting hole 27c Positioning Pin 28 Coil 29 Yoke 30 Hall element 32 Magnetic rod

Claims (4)

  A substrate having a plate-like portion having both the first surface and the second surface, the substrate disposed in the projector such that the first surface is on the optical path side of the light source light; The rotation axis of each rotor is attached to the plate-like part so that the rotation axis of each rotor is perpendicular to the second surface at the positions on both sides of the closest line parallel to the optical axis of the light source light. The first and second electromagnetic actuators, each of which is reciprocally operated in a predetermined angle range, protrudes perpendicularly to the first surface side, and the rotation shaft of the first electromagnetic actuator corresponds to the rotating shaft. A first shaft erected on the first surface side at a predetermined position between a position on the first surface side and an operation locus of the output pin of the first electromagnetic actuator, and the rotation of the second electromagnetic actuator Position on the first surface side corresponding to the axis And a second shaft erected on the first surface side at a predetermined position between the first electromagnetic actuator and the operation locus of the output pin of the second electromagnetic actuator, and a first light shielding plate portion that partially shields the optical path A first mounting piece that is formed substantially perpendicular to the first light shielding plate and is rotatably attached to the first shaft, the first mounting piece being a mounting portion for the first shaft. A first aperture member having a long hole on the first light-shielding plate portion side and fitting the output pin of the first electromagnetic actuator into the long hole, and partially blocking the light path. A second light-shielding plate portion and a second attachment piece that is formed substantially perpendicular to the second light-shielding plate portion and is rotatably attached to the second shaft. An elongated hole is provided on the second light shielding plate side of the mounting portion with respect to the second shaft, and the second electromagnetic actuator is disposed in the elongated hole. A second throttle member into which the output pin of the rotor is fitted, and the two throttle members are in opposite directions by simultaneously rotating the rotors of the two electromagnetic actuators in opposite directions. An aperture device for a projector, characterized in that it can be rotated to the right.   The two diaphragm members are formed so that the shortest linear dimension from each attachment portion of each attachment piece to a virtual surface extending each light shielding plate portion is substantially the same. The electromagnetic actuators are configured so that each of the rotation axes is relatively displaced in the length direction of the line on both sides of the closest line parallel to the optical axis on the second surface. The projector diaphragm device according to claim 1, wherein the diaphragm device is attached to the projector.   The plate-like portion is provided with a stopper on the first surface, with which the mounting pieces come into contact when the two diaphragm members are relatively rotated in a direction to close the optical path. Each member has an aperture opening forming edge, and when the member is stopped in contact with the stopper, the aperture opening forming edge forms a minimum aperture opening centered on the optical axis. 3. The projector diaphragm device according to claim 1, wherein   The base has a second plate-like portion on the opposite side of the plate-like portion with the optical path in between, and the first axis and the surface of the second plate-like portion on the optical path side The third shaft is erected so as to be opposed, and the fourth shaft is erected so as to be opposed to the second axis, and the first diaphragm member is opposite to the first light shielding plate portion. A third attachment piece formed symmetrically with the first attachment piece on the side, the third attachment piece is rotatably attached to the third shaft, and the second aperture The member has a fourth mounting piece formed so as to be symmetrical with the second mounting piece on the opposite side of the second light shielding plate portion, and the fourth mounting piece can be rotated about the fourth shaft. The projector diaphragm device according to claim 1, wherein the diaphragm device is attached to the projector.

Images