JP4812702B2 - Aperture device - Google Patents

Description

  The present invention relates to an aperture device that can be used in a camera, a projector, or the like.

  Among diaphragm devices used for cameras, projectors, etc., the main plate has an elongated shape as a whole, and the diaphragm blades arranged in the blade chamber have a smaller aperture than the optical path opening formed in the main plate. It is known that it has a portion and is linearly reciprocated along the longitudinal direction of the main plate by the driving means so that its aperture opening is moved back and forth to the optical path opening of the main plate. Therefore, in the case of this type of diaphragm device, only one diaphragm aperture can be selected. The following Patent Document 1 describes such a diaphragm device, which is configured to be used in various projectors. In this way, one diaphragm blade (in Patent Document 1) is described. The diaphragm device that selects one diaphragm aperture by operating the diaphragm plate linearly can also be used in various cameras.

  Similarly to the above, the base plate on which the optical path opening is formed has an elongated shape as a whole, but two diaphragm blades having a diaphragm opening forming edge are arranged in the blade chamber, and the drive means A diaphragm device is also known in which a plurality of diaphragm apertures are controlled continuously or stepwise by linearly operating the diaphragm blades in opposite directions. Patent Document 2 below describes such an aperture device, which is mainly configured for use in a video camera. The two aperture blades are operated linearly. Thus, the diaphragm device that selects a plurality of diaphragm apertures can be employed as a diaphragm device for a still camera or a diaphragm device for a projector. Furthermore, this type of diaphragm device can also be configured to select only one diaphragm aperture.

  In addition, the diaphragm devices described in Patent Documents 1 and 2 are configured such that the diaphragm blades are operated by being guided by the guide means. The guide means described in Patent Document 1 is a groove having a U-shaped cross section formed by bending both ends in the width direction of the main plate, and both ends in the width direction slide in the grooves. It is supposed to be. Therefore, the diaphragm blade itself is not required to have a special shape. Moreover, the guide means described in Patent Document 2 is a plurality of guide pins that are erected in the vicinity of both ends in the width direction of the main plate. Therefore, each of the two diaphragm blades has a long hole in the vicinity of both ends in the width direction, and the long hole formed in the vicinity of both ends is fitted to the guide pin. Yes. The present invention relates to a support structure for a diaphragm blade in a diaphragm device that reciprocates the diaphragm blade in the longitudinal direction of the main plate.

JP 2005-164942 A No. 6-37402

  In the case of an aperture device, it is required that the aperture blades operate quickly and smoothly. However, the aperture for a camera that automatically changes the size of the aperture opening in response to changes in the subject light. In the case of an aperture device for a projector that automatically changes the size of the aperture opening in response to changes in the device and image conditions, smooth response is required in response to changes in the amount of light. Therefore, such a request is particularly great. However, the demand for the diaphragm device is not only that, but there is also a great demand for the diaphragm blades to accurately control such a diaphragm aperture over a long period of time. In the case of a diaphragm device for a video camera or a diaphragm device for a projector However, it is required that the noise of the diaphragm blades is also suppressed.

  Looking at the diaphragm device described in Patent Document 1 from such a point of view, the diaphragm blades are always in contact with the guide portion over the entire length in the width direction. When is operated, there is a problem that it is difficult to obtain a suitable responsiveness and an operation sound is likely to be generated. In addition, in the case of the diaphragm device described in Patent Document 2, in order to prevent the two diaphragm blades from each other or the ground plate and diaphragm blades constituting the blade chamber to be almost in surface contact with each other, Since the guide pins and the long holes of the diaphragm blades are specially shaped, there is a problem that the manufacturing becomes difficult and the cost is increased.

  The present invention has been made in order to solve such problems, and an object of the present invention is to provide a guide pin standing on a base plate like a diaphragm device described in Patent Document 2. To provide a diaphragm device that can be manufactured at low cost without complicating the shape of the long hole formed in the diaphragm blade and the shape of the diaphragm blade, and that can operate smoothly and suppress the generation of operating noise. It is.

In order to achieve the above object, each of the diaphragm devices of the present invention has an opening for an optical path, the planar shape is an elongated shape, and one of them is in the blade chamber formed between the two. Fits two ground planes in which the first and second support shafts are erected in the vicinity of both ends in the width direction orthogonal to the longitudinal direction, the aperture opening smaller than the opening, and the first support shaft A diaphragm blade that has a long hole combined and is reciprocated without contacting the second support shaft in the longitudinal direction of the main plate by a driving means, each of which has a ring shape, have and a four space restricting member which is rotatably fitted two by two with between the diaphragm blades relative to the support shaft, when said diaphragm blades is operated, before Symbol second support shaft at least one of the diaphragm blades of the two space restricting member is fitted To so that is rotated by reciprocating.

  In that case, the driving means is an electromagnetic actuator which is composed of a stator having a coil and a rotor capable of reciprocating rotation having a permanent magnet, and is attached to one of the two ground planes. A radially extending arm portion is provided, and an output pin formed at the tip of the arm portion is rotatably fitted in a hole formed in the aperture blade in the blade chamber. Then, it becomes a practical configuration.

In order to achieve the above-described object, the diaphragm device of the present invention has an aperture for an optical path, and has an elongated planar shape . One was fitted to the two ground planes in which the first support shaft and the second support shaft are erected in the vicinity of both ends in the width direction orthogonal to the longitudinal direction, the aperture opening forming edge, and the first support shaft A first aperture blade that has a long hole and can be reciprocated without contacting the second support shaft in the longitudinal direction of the main plate by the driving means; and an aperture opening forming edge and the second support shaft. And has a combined long hole and is reciprocated simultaneously with the first diaphragm blade without contacting the first support shaft in a direction opposite to the first diaphragm blade by the driving means. The opening forming edge and the aperture opening forming edge of the first aperture blade are smaller than the opening. A second diaphragm blade that forms an aperture opening, each ring-shaped, and is rotatably fitted to the two support shafts three by three, and is fitted adjacent to one of the two ground planes Is arranged between the main plate and the first diaphragm blade and fitted in the middle is arranged between the two diaphragm blades and is fitted adjacent to the other of the two main plates. Is provided with six spacing regulating members arranged between the main plate and the second diaphragm blades, and when the two diaphragm blades are operated, the first support Of the three spacing regulating members fitted to the shaft, at least one of the two spacing regulating members other than the spacing regulating member disposed between one of the two ground planes and the first diaphragm blade. Is rotated by the reciprocating operation of the second aperture blade. And two of the three spacing regulating members fitted to the second support shaft other than the spacing regulating member disposed between the other of the two ground plates and the second diaphragm blade. At least one of the space restricting member may be so that is rotated by the reciprocating operation of the first diaphragm blade.

  In that case, the driving means is an electromagnetic actuator which is composed of a stator having a coil and a rotor capable of reciprocating rotation having a permanent magnet, and is attached to one of the two ground planes. A first arm portion and a second arm portion extending in opposite radial directions, and an output pin formed at the tip of each arm portion is provided on each diaphragm blade in the blade chamber, respectively. If it is made to fit in the formed hole so that rotation is possible, it will become a practical structure.

  Moreover, in the diaphragm | throttle device of this invention, the front-end | tip of the said output pin is inserted in the circular-arc-shaped long hole formed in the other of the said two ground plates, and the other of the said two ground plates is inserted in this output pin. If the ring-shaped interval regulating member is rotatably fitted so as to be disposed between the diaphragm blade and the diaphragm blade, an advantageous configuration can be obtained when the drive means is an electromagnetic actuator. . Further, in the diaphragm device of the present invention, when the distance regulating member is made of fluororesin, the diaphragm blades can be operated more smoothly, and the silence is excellent. .

  In the diaphragm device of the present invention, a plurality of ring-shaped interval regulating members are rotatably fitted to two support shafts erected on the base plate, and the diaphragm blades have both end portions in the width direction. Is arranged between each two spacing regulating members attached to each spindle, and a long hole formed only at one end in the width direction is fitted to one spindle. As a result, the end portion that does not form the elongated hole in the width direction can rotate the gap regulating member during operation, and the friction resistance force is smaller than before and operates smoothly. In addition to suppressing the generation of operating noise, it is also very advantageous in terms of cost.

  The embodiment of the present invention will be described with reference to two illustrated examples. The present invention can be applied to a diaphragm device for a camera such as a still camera or a video camera. However, all the embodiments are configured as a diaphragm device for a projector. 1 to 4 are for explaining the first embodiment, and FIGS. 5 to 8 are for explaining the second embodiment.

  First, the first embodiment will be described with reference to FIGS. 1 to 4, but this embodiment is configured as a diaphragm device that can control only one diaphragm aperture. FIG. 1 is a plan view showing a state in which the opening formed in the base plate regulates the optical path, and FIG. 2 is a cross-sectional view showing the overlapping state of the constituent members in an easy-to-understand manner. FIG. 3 is a cross-sectional view taken along line AA of FIG. 1, and FIG. 4 is a plan view showing a state in which the aperture opening formed in the aperture blade restricts the optical path.

  First, the configuration of this embodiment will be described. The base plate 1 is made of a heat-resistant synthetic resin and has a long and narrow rectangular shape. In FIG. 1, a circular optical path opening 1a is provided slightly on the right side of the center, in the vicinity of the left end. The part has a large irregularly shaped opening 1b. An auxiliary base plate 2 is attached to the base plate 1 by an appropriate means, and a blade chamber is formed between the base plate 1 and the base plate 1. In FIG. Only is shown (not shown in FIG. 4). The auxiliary base plate 2 is made of metal and has substantially the same outer shape as the base plate 1, but in the case of this embodiment, the auxiliary base plate 2 is arranged in the projector with the auxiliary base plate 2 as the light source side. Yes. The auxiliary base plate 2 is also formed with an opening having the same shape (not shown) at a position facing the opening 1a.

  Two support shafts 1c and 1d are erected on the blade chamber side surface of the base plate 1 in the vicinity of both ends in the width direction. As can be seen from FIG. 3, these support shafts 1 c and 1 d have the same shape and are erected on a circular thick portion formed on the base plate 1. Are fitted in the holes. Also, ring-shaped interval regulating members 3 and 4 are rotatably attached to the spindle 1c, and two interval regulating members 5 and 6 having the same shape are also rotatably attached to the spindle 1d. However, in the case of the present embodiment, these spacing regulating members 3, 4, 5, and 6 are made of a fluororesin (for example, a trade name “Teflon (registered trademark: EI Deyupon Dow Nemours and・ Company) ”), and it is movable in the axial direction.

  A diaphragm blade 7 is also attached to the support shaft 1c. As shown in FIG. 1, the diaphragm blade 7 of this embodiment has an opening 7a having a diameter larger than that of the opening 1a of the main plate 1 and a diaphragm opening 7b having a diameter smaller than that of the opening 1a. In addition, a circular hole 7c is provided in the vicinity of the left end, a long hole 7d is provided on one side in the width direction, and the long hole 7d is fitted to the support shaft 1c. Therefore, as can be seen from FIG. 3, the diaphragm blade 7 has the long hole 7d fitted to the support shaft 1c between the spacing regulating members 3 and 4, but the other end side in the width direction is supported on the other end side. It is only arranged between the space regulating members 5 and 6 attached to the shaft 1d.

  Thus, as the long hole formed in the diaphragm blade 7 of the present embodiment, only one of the long holes 7d is attached to the support shaft 1c. Moreover, the long hole 7d and the support shaft 1c are not in a complicated shape unlike those described in Patent Document 2, and only have a very simple shape. Moreover, the space | interval control members 3, 4, 5, and 6 are common parts with a simple shape, and only fit in order to the support shafts 1c and 1d. For this reason, the arrangement of the diaphragm blades 7 to the main plate 1 is very advantageous in terms of cost because the related parts can be easily processed and the assembling work can be easily performed.

  An electromagnetic actuator is attached to the surface outside the blade chamber of the base plate 1 as a driving means for the diaphragm blade 7. This electromagnetic actuator is described in, for example, the first embodiment of Japanese Patent Application Laid-Open No. 2005-24638. This is a known current control type motor. The first stator frame 8 has a cup-shaped shape, and constitutes a housing chamber for the rotor 10 between the first stator frame 8 and the second stator frame 9. The rotor 10 having a permanent magnet is supported by both of the stator frames 8 and 9 in the accommodation chamber. Grooves are formed on the outer sides of the stator frames 8 and 9 so as to surround those bearing portions, and a coil 11 is wound around the grooves, and a cylindrical yoke 12 is disposed outside the coil 11. The first stator frame 8 is fitted. The rotor 10 has a rotor shaft made of synthetic resin, and an output pin 10a is formed at the tip of an arm portion that is integral with the rotor shaft and extends in the radial direction from the housing chamber. It is also known that the output pin 10a is made of a permanent magnet including the arm portion.

  The motor of this embodiment configured in this way is partially inserted into the blade chamber side from the opening 1b of the base plate 1, and the second stator frame 9 is connected with the two screws 13,14. By screwing, it is attached to the surface of the main plate 1 outside the blade chamber. In the mounted state, the output pin 10a is rotatably fitted to the hole 7c of the aperture blade 7 and the interval regulating member 15 shown in FIG. 2, and its tip is attached to the auxiliary base plate 2. It is inserted into an arc-shaped elongated hole 2a formed around the rotation axis of the rotor 10. In addition, the space | interval control member 15 is a component common with said space | interval control members 3-6. Further, as can be seen from the following description of the operation, it is more preferable than the case of this embodiment to fit another gap regulating member on the opposite side of the diaphragm blade 7.

  In the case of the present embodiment, the current control type motor configured as described above is adopted as the driving means for the diaphragm blades 7, but the driving means of the present invention is limited to such a motor. is not. Even if it is an electric current control type motor, various things are known mainly by the difference in the composition of the stator. In addition, as a driving means for the diaphragm blades, it is conventionally known to employ a step motor or an electromagnetic plunger, and it is also known to employ a DC motor as described in Patent Document 1. . Accordingly, the driving means of the present invention may be any of them. This also applies to the case of Example 2 below.

  Next, the operation of this embodiment will be described. FIG. 1 shows a state in which the opening 1a of the base plate 1 regulates the optical path of irradiation light. At this time, no current is supplied to the coil 11. However, as is well known, an attractive force acts between the permanent magnet of the rotor 10 and the magnetic member provided on the first stator frame 8, and the rotor 10 rotates clockwise. Although a force is applied, this state is reliably maintained by preventing the rotation by a stopper (not shown). In this state, when it is desired to reduce the aperture of the optical path in order to reduce the brightness of the irradiation light, a forward current is supplied to the coil 11. Accordingly, the rotor 10 is rotated counterclockwise, so that the aperture blade 7 is moved substantially in the left direction.

  At this time, the diaphragm blade 7 slides with respect to the support shaft 1c, but does not contact the support shaft 1d and does not contact the base plate 1 or the auxiliary base plate 2, and thus operates smoothly and operates. The sound is low. Further, at this time, the diaphragm blade 7 is in sliding contact with at least one of the interval regulating members 3 and 4, but there is no surface contact between them, and there is a case where they are in contact with each other at an angle. When the operation is performed, the interval regulating members 3 and 4 are rotated, so that the operation is smoother and the operation noise is suppressed. Further, at this time, the diaphragm blade 7 is also in sliding contact with at least one of the distance regulating members 5 and 6 attached to the support shaft 1d. However, the lower end portion of the diaphragm blade 7 does not contact the support shaft 1d, and is in sliding contact with at least one of the space control members 5 and 6 above the position of the support shaft 1d. It is rotated by the friction of time, has little effect on the movement of the aperture blade 7, and hardly generates an operating noise.

  Furthermore, in the case of the present embodiment, the diaphragm blade 7 is connected to the cylindrical output pin 10a by the circular hole 7c, so that the frictional resistance force at the connecting portion is small and the operating noise is reduced. Occurrence is also suppressed. Further, due to the presence of the space regulating member 15, the frictional resistance between the diaphragm blade 7 and the vicinity of the elongated hole 2 a of the auxiliary base plate 2 is also relieved. Further, when the diaphragm blade 7 is sandwiched between the space regulating member 15 and the other space regulating member, the diaphragm blade 7 does not directly contact the synthetic resin arm portion provided with the output pin 10a. Become more effective. However, in the present invention, it is not essential to attach an interval regulating member to the output pin 10a. In the present embodiment, all the spacing regulating members are made of fluororesin, but some or all of them may be made of a material other than fluororesin. These also apply to the case of Example 2 below.

  In this way, in FIG. 1, when the diaphragm blade 7 moves substantially leftward, the diaphragm opening 7 b formed in the diaphragm blade 7 eventually enters the opening 1 a of the base plate 1. When the center of the aperture opening 7b coincides with the center of the aperture 1a, the rotation of the rotor 10 and the movement of the aperture blade 7 are prevented by a stopper (not shown). FIG. 4 shows the state at that time. In this state, the power supply to the coil 11 is cut off. At this time, as is well known, the coil 11 acts between the permanent magnet of the rotor 10 and the magnetic member provided on the first stator frame 8. Since the rotating force is applied to the rotor 10 in the counterclockwise direction by the suction force that is generated, the state of FIG. 4 is reliably maintained.

  In order to increase the brightness of the irradiation light, when the diaphragm blade 7 is moved from the position shown in FIG. 4 to the position shown in FIG. Supply. As a result, the rotor 10 is rotated in the clockwise direction, so that the diaphragm blade 7 is moved substantially to the right. At this time, too, the diaphragm blade 7 is large for the reason already described. It moves smoothly without generating an operating sound. When the position shown in FIG. 1 is reached, rotation of the rotor 10 and movement of the aperture blade 7 are prevented by a stopper (not shown), and immediately after that, the coil 11 is deenergized. In the case of the present embodiment, even when projection by the projector is completed in the state of FIG. 4 and the power is turned off, the delay circuit is activated, and the diaphragm blade 7 is operated during the delay time. Is automatically returned to the position shown in FIG.

  Next, Example 2 will be described with reference to FIGS. In this embodiment, as in the case of the first embodiment, it is possible to control only one stop aperture, but it is also possible to control the stop aperture continuously or stepwise. For this reason, a description will be given of a case in which the aperture opening is continuously controlled. And FIG. 5 is a plan view showing a state where the opening formed in the ground plate regulates the optical path, and FIG. 6 is a cross-sectional view showing the overlapping state of the constituent members in an easy-to-understand manner, FIG. 7 is a cross-sectional view taken along the line BB in FIG. 5, and FIG. 8 is a plan view showing a state in which the minimum aperture is formed by the aperture aperture forming edges of the two aperture blades.

  First, the configuration of this embodiment will be described. The base plate 21 is made of a heat-resistant synthetic resin and has a long and narrow rectangular shape in plan view. In addition to the circular optical path opening 21a, the base plate 21 has a large irregularly shaped opening 21b in the vicinity of the left end. is doing. The auxiliary base plate 22 is made of metal and has substantially the same outer shape as the base plate 21 and is attached to the base plate 21 by an appropriate means to form a blade chamber between the base plate 21. In FIG. Is only partly shown in the upper right. The auxiliary base plate 22 is also formed with an opening having the same shape (not shown) at a position facing the opening 21a.

  Two support shafts 21c and 21d are erected on the surface on the blade chamber side of the base plate 21 in the vicinity of both ends in the width direction. These support shafts 21c and 21d have exactly the same shape, and are erected on a circular thick portion formed on the main plate 21 as in the case of the support shaft 21d shown in FIG. The small diameter portion at the tip is fitted into the hole of the auxiliary base plate 22. Further, on the support shaft 21c, three interval regulating members 23, 24, 25 made of a fluororesin and in a ring shape are attached in turn so that the interval regulating member 23 is the first base plate 21 side. Also, three interval restriction members 26, 27, and 28 of the same shape and the same material are attached to the support shaft 21d so as to be rotatable in order with the interval restriction member 26 being the first base plate 21 side.

  Two diaphragm blades 29 and 30 are arranged in the blade chamber. As shown in FIG. 5, among them, the diaphragm blade 29 arranged on the base plate 21 side has an opening 29 a larger than the opening 21 a of the base plate 21, and in the vicinity of the left end. Has a circular hole 29b and a long hole 29c on one side in the width direction. Among them, the opening 29a has only a semicircular edge on the right half, but an edge on the left half is formed as a diaphragm opening forming edge. The diaphragm blade 29 has a long hole 29c fitted to the support shaft 21c between the spacing regulating members 23 and 24, and the other end side in the width direction is as shown in FIG. , Between the spacing regulating members 26 and 27 attached to the support shaft 21d.

  On the other hand, the aperture blade 30 has an opening 30a larger than the opening 21a of the main plate 21, a circular hole 30b in the vicinity of the left end, and a long hole 30c on one side in the width direction. is doing. Among them, the opening 30a has a symmetrical shape with the opening 29a of the diaphragm blade 29, and the left half edge is only semicircular, but the right half edge. Is formed as a diaphragm opening forming edge. As shown in FIG. 7, the diaphragm blade 30 has a long hole 30c fitted to the support shaft 21d between the interval regulating members 27 and 28, and the other end side in the width direction is , Between the spacing regulating members 24 and 25 attached to the support shaft 21c.

  Thus, also in the case of the present embodiment, the diaphragm blades 29 and 30 are only formed with the long holes 29c and 30c one by one, and can be attached only to one of the support shafts 21c and 21d. It has become. In addition, the long holes 29c and 30c and the support shafts 21c and 21d have a simple shape like the long holes 7d and the support shafts 1c and 1d in the first embodiment. Moreover, the space | interval control members 23, 24, 25, 26, 27, and 28 are ring-shaped common parts. For this reason, the diaphragm blades 29 and 30 in the present embodiment are also very advantageous in terms of cost because the related parts can be easily processed and the assembly work can be easily performed.

  One electromagnetic actuator is attached to the surface outside the blade chamber of the base plate 21 as a common drive means for the two diaphragm blades 29 and 30. The electromagnetic actuator of the present embodiment is a current control type motor having the configuration described in the second embodiment of the above-mentioned Japanese Patent Application Laid-Open No. 2005-24638. The motor described in the first embodiment is Only some configurations are different.

  As shown in FIG. 6, a housing chamber for a rotor 33 is formed between the first stator frame 31 and the second stator frame 32, and the rotor 33 having a permanent magnet Are supported by the stator frames 31 and 32. A series of grooves are formed outside the stator frames 31 and 32 so as to surround the bearing portion of the rotor 33, and coils 34 and 35 are wound in the grooves in order from the bottom. Further, in the outer peripheral surface of the first stator frame 31, where a groove around which the coils 34 and 35 are wound is not formed, a recess not shown in the shape of a depression is formed, Although not shown, a hall element (magnetic sensitive element) capable of detecting the rotational position of the rotor 33 is accommodated. A cylindrical yoke 36 is fitted to the first stator frame 31 so as to enclose the coil 35 and the Hall element. The rotor 33 has a rotor shaft made of synthetic resin, is integrally formed with the rotor shaft, and has two output pins 33a, 33b is formed.

  The motor of this embodiment is partially inserted into the blade chamber side from the opening 21b of the base plate 21, and the second stator frame 32 is screwed with the two screws 37 and 38. The base plate 21 is attached to a surface outside the blade chamber. In the attached state, the output pin 33a is rotatably fitted to the hole 29b of the aperture blade 29 and the interval regulating member 39 shown in FIG. It is inserted into the formed long hole 22a. Further, the other output pin 33b is rotatably fitted to the hole 30b of the aperture blade 30 and the interval regulating member 40 shown in FIG. 6, and its tip is formed on the auxiliary base plate 22. It is inserted into the long hole 22b. Even in the case of the present embodiment, it is more preferable to attach another spacing regulating member to the output pins 33a and 33b with the diaphragm blades 29 and 30 therebetween. Further, the long holes 22 a and 22 b are actually formed in an arc shape around the rotation axis of the rotor 33.

  Next, the operation of this embodiment will be described. As described above, the two coils 34 and 35 are wound around both the stator frames 31 and 32 of the present embodiment, but when a forward current is supplied to the coil 34, In FIG. 5, when a rotational force that rotates the rotor 33 counterclockwise is generated and a forward current is supplied to the coil 35, a rotational force that rotates the rotor 33 clockwise is generated. It is configured. And those rotational forces become so large that a big electric current is supplied. Therefore, when the current values supplied to the coils 34 and 35 are the same, the rotor 33 does not rotate in any direction, and the stopped state is maintained.

  By the way, the state shown in FIG. 5 shows a non-use state of the projector. Therefore, no current is supplied to any of the coils 34 and 35. When the power is turned on when the projector is used, a forward current is supplied to both the coils 34 and 35. When making the irradiation light the strongest, a Hall element (not shown) detects that the rotor 33 is at the position shown in FIG. 5, and the coils 34 and 35 are supplied with the same current. . Therefore, the rotor 33 remains stopped at the position shown in FIG. 5, and the optical path of the illumination light is regulated by the opening 21 a of the main plate 21.

  In order to weaken the illumination light, when reducing the opening of the optical path, the current supplied to the coil 35 is made larger than the current supplied to the coil 34. As a result, the rotor 33 rotates in the clockwise direction in FIG. 5, but the rotation speed depends on the difference between the current values supplied to the coils 34 and 35. Thus, when the rotor 33 rotates clockwise, the diaphragm blade 29 is moved substantially right by the output pin 33a, and the diaphragm blade 30 is moved substantially left by the output pin 33b. The optical path is regulated by the aperture opening obtained by the cooperation of the aperture opening forming edges of the two aperture blades 29 and 30. As the rotor 33 rotates in the clockwise direction, the aperture opening becomes smaller.

  In this way, when the rotor 33 rotates clockwise and the aperture opening reaches a predetermined size, the current values supplied to the coils 34 and 35 become the same corresponding to the detection result by the Hall element. Thus, the rotation of the rotor 33 is stopped and the stopped state is maintained. After that, when it is desired to increase the illumination light, the current supplied to the coil 34 is made larger than the current supplied to the coil 35, and when it is desired to be weaker, the current supplied to the coil 34 is set. The current supplied to the coil 35 is increased to change the aperture opening as needed. FIG. 8 shows a state when the aperture stop is made the smallest in this way.

  By the way, when the two diaphragm blades 29 and 30 are moved in this manner, they slide only with respect to one of the support shafts 21c and 21d and do not contact with the other at all. In addition, the base plate 21 and the auxiliary base plate 22 are not in contact with each other and are not in contact with each other. Therefore, the two diaphragm blades 29 and 30 operate smoothly, and the generation of operation noise is also suppressed. Further, at this time, the diaphragm blades 29 and 30 do not come into contact with the unsupported support shaft, and the distance regulating member attached to the support shaft has a base plate 21 rather than the support shaft. Since the sliding contact is made at the center side in the width direction, the spacing regulating member is rotated by the sliding contact, and the spacing regulating member attached to the attached spindle may also be rotated. Therefore, the operation is further smoothed and the generation of operation noise is suppressed.

  Furthermore, also in the case of the present embodiment, the diaphragm blades 29 and 30 are connected to the cylindrical output pins 33a and 33b by the circular holes 29b and 30b, so that the frictional resistance force at the connecting portion is small. Also, the generation of operating noise is suppressed. Further, the presence of the space regulating members 39 and 40 also reduces the frictional resistance between the diaphragm blades 29 and 30 and the vicinity of the long holes 22a and 22b of the auxiliary base plate 22. Further, when another spacing regulating member is fitted to the output pins 33a and 33b on the opposite side of the aperture blades 29 and 30, the aperture blades 29 and 30 are provided with the output pins 33a and 33b. It is no longer in direct contact with the arm portion made of synthetic resin, and is more effective.

  In this way, projection is performed by the projector, and when it is finished, the power is turned off. At this time, since the delay circuit is also activated in this embodiment, the rotor 33 is rotated counterclockwise during the delay time and returned to the position shown in FIG. 5 and stopped.

In each of the above embodiments, the output pin integral with the rotor is directly connected to the aperture blade, but the present invention is not limited to such a configuration, and other members are used. You may make it connect via. For example, when the two diaphragm blades are operated in opposite directions as in the second embodiment, the drive member is rotatably attached to one of the main plates, and the drive is performed at different radial positions from the rotation center. The two pins provided on the member are fitted into the apertures of the aperture blades like the output pins 33a and 33b, and the drive member is reciprocally rotated by the output pin of the rotor. It is possible. In such a case, it is not necessary to provide the two output pins 33a and 33b as in the rotor 33 of the second embodiment, and one output pin 10a as in the rotor 10 of the first embodiment. Needless to say, it's OK.

  In addition, each of the above embodiments has been described on the assumption of a diaphragm device for various projectors. However, the diaphragm device of the present invention can be used as a diaphragm device for a camera or a lighting device that performs stage lighting or the like. Can also be implemented.

It is the top view of Example 1 which showed the state which the opening part currently formed in the baseplate has controlled the optical path. It is sectional drawing of Example 1 which showed the overlapping state of the structural member easily. It is the sectional view on the AA line of FIG. It is the top view of Example 1 which showed the state which the aperture_diaphragm | restriction opening part currently formed in the aperture blade has controlled the optical path. It is the top view of Example 2 which showed the state which the opening part currently formed in the baseplate has controlled the optical path. It is sectional drawing of Example 2 which showed the overlapping state of the structural member easily. FIG. 6 is a sectional view taken along line BB in FIG. 5. It is a top view of Example 2 which shows the state which formed the minimum aperture opening by the aperture opening formation edge of two diaphragm blades.

Explanation of symbols

1,21 Ground plate 1a, 1b, 7a, 21a, 21b, 29a, 30a Opening 1c, 1d, 21c, 21d Support shaft 2,22 Auxiliary ground plate 2a, 7d, 29c, 22a, 22b Long holes 3-6, 15, 23-28, 39, 40 Spacing regulating member 7, 29, 30 Aperture blade 7b Aperture opening 7c, 29b, 30b Hole 8, 31 First stator frame 9, 32 Second stator frame 10, 33 Rotor 10a, 33a, 33b Output pin 11, 34, 35 Coil 12, 36 Yoke 13, 14, 37, 38 Screw

Claims (6)

Each has an opening for the optical path, and the planar shape is elongated. Either one of the first supports is provided in the vicinity of both ends in the width direction perpendicular to the longitudinal direction in the blade chamber formed therebetween. The main plate has two shafts erected on the shaft and the second support shaft, a throttle opening smaller than the opening, and a long hole fitted in the first support shaft. A diaphragm blade that can be reciprocated without contacting the second support shaft in the longitudinal direction, and each of the diaphragm blades is ring-shaped and rotates two by two with the diaphragm blade in between. at least one of the possible and four space restricting member so are fitted, provided with a, the when the diaphragm blades is operated, the front Symbol the two space restricting member is fitted to the second spindle It is especially that it has to so that is rotated by the reciprocating operation of the diaphragm blades And the throttling device.   The driving means is an electromagnetic actuator which is composed of a stator having a coil and a rotor capable of reciprocating rotation having a permanent magnet, and is attached to one of the two ground planes. And an output pin formed at the tip of the arm is rotatably fitted in a hole formed in the diaphragm blade in the blade chamber. The diaphragm device according to claim 1. Each has an opening for the optical path, and the planar shape is elongated. Either one of the first supports is provided in the vicinity of both ends in the width direction perpendicular to the longitudinal direction in the blade chamber formed therebetween. The base plate has two shafts erected on the shaft and the second support shaft, an aperture opening forming edge, and a long hole fitted to the first support shaft, and is driven in the longitudinal direction of the base plate by driving means. It has a first diaphragm blade that can be reciprocated without contacting the second spindle, a diaphragm opening forming edge, and a long hole fitted to the second spindle, and the first means by the driving means. The diaphragm opening is reciprocated simultaneously with the first diaphragm blade without contacting the first support shaft in a direction opposite to the diaphragm blade, and the diaphragm opening forming edge and the diaphragm opening forming edge of the first diaphragm blade A second diaphragm blade that forms a diaphragm aperture smaller than the aperture, and each ring-shaped And three that are rotatably fitted to the two support shafts and that are fitted adjacent to one of the two ground plates are disposed between the ground plate and the first diaphragm blade. The one fitted in the middle is disposed between the two diaphragm blades, and the one fitted adjacent to the other of the two ground plates is disposed between the ground plate and the second diaphragm blades. Six interval restriction members, and when the two diaphragm blades are operated, of the three interval restriction members fitted to the first support shaft, the two interval restriction members are provided. At least one of the two spacing regulating members other than the spacing regulating member disposed between one of the two base plates and the first diaphragm blade is rotated by the reciprocating operation of the second diaphragm blade. The three intervals fitted to the second spindle Among the control members, at least one of the two spacing regulating members other than the spacing regulating member disposed between the other of the two ground planes and the second diaphragm blade is caused by a reciprocating operation of the first diaphragm blade. throttling device being characterized in that the so that rotated.   The drive means is an electromagnetic actuator which is composed of a stator having a coil and a rotor capable of reciprocating rotation having a permanent magnet, and is attached to one of the two ground planes. A first arm portion and a second arm portion extending in the radial direction are provided, and output pins formed at the tips of the arm portions are respectively formed in the diaphragm blades in the blade chamber. The aperture device according to claim 3, wherein the aperture device is rotatably fitted in the hole.   The tip of the output pin is inserted into an arc-shaped slot formed in the other of the two ground plates, and the output pin is disposed between the other of the two ground plates and the aperture blade. The aperture device according to claim 2 or 4, wherein a ring-shaped interval regulating member is rotatably fitted.   The aperture device according to any one of claims 1 to 5, wherein the spacing regulating member is made of a fluororesin.

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