Patent Publication Number: US-2003231256-A1

Title: Movable part locking device

Description:
BACKGROUND OF THE INVENTION  
       [0001] 1. Field of the Invention  
       [0002] The present invention relates to a protective mechanism in an appliance such as an image pickup apparatus, particularly, to a movable part locking device which is adapted to lock a movable part of the appliance in order to protect such precision appliances from vibrations or shocks during transportation.  
       [0003] 2. Description of the Related Art  
       [0004] There has been known a movable part locking device for protecting precision appliances such as an image pickup apparatus from vibrations or shocks during transportation so as to prevent the appliance from being damaged. Such movable part locking device has been used, for example, in an iris image pickup apparatus to be employed in security systems. The iris image pickup apparatus includes a wide angle camera for picking up an image of a subject in a wide range, and a telephoto camera for picking up a enlarged image of the iris of the subject. Identification of individuals can be operated by the iris images picked up by the telephoto camera. The applicant has proposed the iris image pickup apparatuses, for example, in U.S. appl. Ser. No. 10/149,884 filed on Jun. 14, 2002 and so on.  
       [0005] The telephoto camera mounted with a tilt stage of the iris image pickup apparatus, especially, in which valuable components such as the camera is included, may sometimes be broken, since the tilt stage rotates by vibrations or shocks during transportation. In order to prevent the tilt stage from rotating, a lock mechanism, for example, for indirectly braking a shaft of the tilt stage as a movable part by a screw which can be accessed from an exterior, thereby to hold and fix the tilt stage, is provided.  
       [0006] However, the lock mechanism as described above has a problem that the screw is positioned in a deep part of the mechanism to see from the front, and hence a locked condition of the tilt stage can be easily confirmed from the exterior. It has another problem that it is difficult to determine whether or not the pivotal shaft is reliably braked and the tilt stage is locked because there are individual differences in screwing torque when the pivotal shaft of the tilt stage is locked. Further, it has another problem it is necessary to take countermeasures as like providing a mechanism for preventing slack of the screw in order to maintain the locked condition in a stabilized state over time. However, the countermeasure incurs high cost by increasing the number of components.  
       SUMMARY OF THE INVENTION  
       [0007] The object of the invention is to provide a movable part locking device which can simply and reliably hold the movable part such as a tilt stage mounted with a telephoto camera by employing a few components, in an appliance such as an image pickup apparatus.  
       [0008] Another object of the invention is to provide the movable part locking device in which a locked state and a released state can be easily confirmed from the exterior.  
       [0009] The invention provides a movable part locking device for locking a movable part contained in a casing, comprises flexible belt means, one end of which is fixed to a determined position inside the casing, and first belt securing means for securing another end of the flexible belt means to a first determined position outside the casing, wherein the flexible belt means is abutted against at least a portion of a periphery of the movable part, and secured the another end of the flexible belt means to the first belt securing means after passing through a first hole formed at a determined position of the casing, thereby to lock the movable part.  
       [0010] According to the above-described structure, the flexible belt means is abutted against the periphery of the movable part of an precision appliance such as the image pickup apparatus, and the another end of the flexible belt means is secured. As the results, the movable part can be locked and reliably held.  
       [0011] Moreover, the movable part locking device further comprises second belt securing means for securing the another end of the flexible belt means to a second determined position outside the casing, wherein the flexible belt means is secured the another end of the flexible belt means to the second belt securing means after passing through the first hole of the casing, thereby to release the movable part which was locked.  
       [0012] According to the above-described structure, the flexible belt means presses the movable part to lock it, when the another end of the flexible belt means is secured to the first securing means, and the flexible belt means releases the movable part to make it free, when the another end of the flexible belt means is secured to the second securing means. Therefore, an operator can easily determine at a glance over a secured position of the flexible belt means whether the movable part is in the locked condition or in the released condition.  
       [0013] Further, the flexible belt means has a plurality of joint portions enabling the flexible belt means to be bent.  
       [0014] According to the above-described structure, bending condition can be restricted according to the position of the flexible belt means to be abutted against the movable part. Therefore, when the movable part is released, the flexible belt means can retreat to a position at which the belt means does not interfere with the movable part, and when the movable part is locked, the flexible belt means can reliably hold the movable part.  
       [0015] Still further, each of the joint portions is shaped to restrict a bending angle in a bending direction, and that a bending repulsive force is created due to this shape, when the flexible belt means is bent at the joint portions.  
       [0016] According to the above-described structure, the flexible belt means can be bent at a determined angle in a determined direction. Therefore, it is possible to make the belt means to reliably retreat and make the movable part free to rotate, when the movable part has been released from the locked state.  
       [0017] Still further, each of the first and second belt securing means is formed by hole in a convex shape, and when the another end of the flexible belt means is inserted into the hole, the another end of the flexible belt means is expanded by the bending repulsive force to be fixed in the hole.  
       [0018] According to the above-described structure, the belt means can be secured by simply bending the end of the belt means and inserting it in the hole of the casing in a convex shape. Therefore, the movable part locking device can be composed of a few components, and at the same time, operability become enhanced.  
       [0019] Still further, the flexible belt means partly has a notch portion, and the casing partly has first guide means for the flexible belt means, wherein the first guide means guides the flexible belt means by way of the notch portion, when the another end of the flexible belt means is secured to the first belt securing means or the second belt securing means.  
       [0020] According to the above-described structure, at the locking operation or the lock releasing operation of the movable part, a displacement of the flexible belt means in a lateral direction can be prevented. Therefore, the movable part can be reliably locked or released.  
       [0021] Still further, the first belt securing means is provided at such a position as the flexible belt means protrudes from an exterior plane of the casing in a state that the flexible belt means is secured to the first belt securing means, and the second belt securing means is provided at such a position as the flexible belt means is located inside the exterior plane of the casing in a state that the flexible belt means is secured to the second belt securing means.  
       [0022] According to the above-described structure, when the casing which contains the movable part is mounted on a wall face or the like with using a casing mounting means, in case that the movable part is locked, an appliance constructed with the movable part and the casing will be unable to be assembled to the casing mounting means, since the flexible belt means which protrudes interferes with the casing mounting means. Therefore, it is possible to prevent the appliance from being fitted to the casing mounting means while the movable part is locked, by mistake.  
       [0023] Still further, the casing has a second hole which is formed at a position to be blocked by the flexible belt means when the flexible belt means has been secured to the first belt securing means, casing mounting means on which the casing is mounted has protruded means which is adapted to be engaged with the second hole of the casing.  
       [0024] According to the above-described structure, when the casing which contains the movable part is mounted on the wall face or the like with using the casing mounting means, in case that the movable part is locked, the appliance will be unable to be assembled to the casing mounting means, since the protruded part of the casing mounting means is abutted against the flexible belt means. Therefore, it is possible to prevent the appliance from being fitted to the casing mounting means while the movable part is locked, by mistake.  
       [0025] Still further, the movable part is a tilt stage of an image pickup apparatus.  
       [0026] According to the above-described structure, the flexible belt means is abutted against a periphery of the tilt stage of the image pickup apparatus, and the another end of the flexible belt means is secured. Therefore, it is possible to lock and reliably hold the tilt stage which is the movable part, and the appliance such as a telephoto camera which is mounted on the tilt stage can be prevented from being damaged.  
       [0027] Still further, the first belt securing means is positioned in the same direction as the tilt stage, and the second belt securing means is positioned in an opposite direction to the tilt stage.  
       [0028] According to the above-described structure, when the tilt stage is locked, because the belt means is abutted against the tilt stage along its periphery to exert a force, it is possible to reliably lock the tilt stage. When the lock is released to use the image pickup apparatus, the flexible belt means is separated from the periphery of the tilt stage, and the tilt stage can be reliably made free to rotate.  
       [0029] Still further, the flexible belt means has at least a fixed portion to be fixed to the casing, an abutted portion to be abutted against a side face of the tilt stage, a shift portion which is straightened when the flexible belt means secures to the first belt securing means and bent when the flexible belt means secures to the second belt securing means, and a fixed portion to be secured to the first and second belt securing means.  
       [0030] According to the above-described structure, because the belt means is abutted against the tilt stage always in the same condition, stability of the tilt stage in the locked condition become enhanced.  
       [0031] Still further the casing has second guide means for the flexible belt means extending from the first hole toward the interior of the casing.  
       [0032] According to the above-described structure, even though the flexible belt means is forced to be inserted into the casing when the tilt stage become locked or released, movement of the flexible belt means is restricted by the second guide means, and operability become enhanced. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0033]FIG. 1 is a front view showing a structure of an iris image pickup apparatus provided with a movable part locking device according to a first and a second embodiments of the present invention;  
     [0034]FIG. 2 is an exploded perspective view showing a structure of the movable part locking device according to a first embodiment of the invention;  
     [0035]FIG. 3A is a plan view of the belt of the first embodiment;  
     [0036]FIG. 3B is a side view of the belt of the first embodiment;  
     [0037]FIGS. 4A, 4B and  4 C are a sectional view showing shapes of joint portions of the belt according to the first embodiment of the invention;  
     [0038]FIG. 5A is a sectional view showing lock-released state of the movable part locking device of the first embodiment;  
     [0039]FIG. 5B is a sectional view showing locked state of the movable part locking device of the first embodiment;  
     [0040]FIG. 6A is a plain view of the belt of a second embodiment;  
     [0041]FIG. 6B is a side view of the belt of a second embodiment;  
     [0042]FIG. 7 is a perspective view showing a structure of a back cover according to the second embodiment of the invention;  
     [0043]FIG. 8A is a sectional view showing lock-released state of the movable part locking device of the second embodiment;  
     [0044]FIG. 8B is a sectional view showing locked state of the movable part locking device of the second embodiment. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
     [0045] In the following embodiments, an iris image pickup apparatus is explained as the appliance to which a movable part locking device of the invention is preferably applied. The following explains a structural example of the iris image pickup apparatus.  
     [0046]FIG. 1 is a front view showing a structure of the iris image pickup apparatus including the movable part locking device of a first and a second embodiments. The iris image pickup apparatus includes a fixed plate  10  formed in a shape of an elongated box. In a leftward bottom part of the fixed plate  10 , a guide part  10   a  for guiding a belt which constitutes the movable part locking device of the invention is uprightly provided as described below. At a back side in a lower area of the fixed plate  10 , a through hole  10   c  for passing the belt through is formed. In addition, in small planes formed by bending four corners of the fixed plate  10  outwardly at right angles in an L-shape, fitting holes  10   b  for fitting the iris image pickup apparatus to a casing described below.  
     [0047] In the bottom part of the fixed plate  10 , support plates  20 ,  21  are uprightly provided, on which a tilt stage  11  having shafts  11   a,    11   b  at both ends is rotatablly supported. A tilt motor  22  is mounted to the support plate  20 . A rotation axis of the tilt motor  22  is connected to one of the shafts  11   a  of the tilt stage  11 .  
     [0048] A telephoto camera  12  for picking up an iris image, a panning mirror  13  which converts an optical axis of the iris image, a panning motor  14  which drives the panning mirror  13 , and illuminating units  15 ,  16  for the telephoto camera are mounted with the tilt stage  11 . The illuminating units  15 ,  16  for the telephoto camera are equipped with light condensing lenses to condense infrared light on an iris of an object person to be recognized, and panning motors  15   a,    16   a  to set direction of the luminous light to the iris. In a leftward lower part of the tilt stage  11 , a lock part  11   c  adapted to be abutted against the belt, which constitutes the movable part locking device as described below, is provided.  
     [0049] The following explains the movable part locking device of each embodiment.  
     [0050] (First Embodiment)  
     [0051]FIG. 2 is an exploded perspective view showing a structure of the movable part locking device of a first embodiment. FIG. 3A is a plan view of the belt of the first embodiment. FIG. 3B is a side view of the belt of the first embodiment. FIGS. 4A, 4B and  4 C are a sectional view showing shapes of joint portions of the belt of the first embodiment. FIG. 5A is a sectional view showing lock-released state of the movable part locking device of the first embodiment. FIG. 5B is a sectional view showing locked state of the movable part locking device of the first embodiment.  
     [0052] As shown in FIG. 2, the fixed plate  10  mounted with the iris image pickup apparatus is contained inside a casing  30  and fixed by screws through the fitting holes  10   b.  One end of a belt  31  is fixed to an inner back face of the casing  30  at a determined position. The other end of the belt  31  is passed through the through hole  10   c  of the fixed plate  10  and extended to a back side of the fixed plate  10 .  
     [0053] A back cover  32  for covering the fixed plate  10  to contain the iris image pickup apparatus is fitted to the casing  30 . The back cover  32  has a releasing hole  32   a  in convex shape for securing the other end of the belt  31  on a face erected backward by cutting from a portion of its rightward lower part, and a detecting hole  32   c  for detecting a mounting hardware described below. A locking hole  32   b  on the same plane as the back cover  32  and in the same shape as the releasing hole  32   a  is provided underneath the releasing hole  32   a  and the detecting hole  32   c.  Mounting holes  32   d  for mounting the casing  30  to the mounting hardware described below, and a guide part  32   e  adapted to be engaged with the through hole  10   c  of the fixed plate  10  thereby to guide the belt  31  so as not to be inserted in an upward direction by mistake are further provided with the back cover  32 .  
     [0054] The casing  30  and the back cover  32  are installed on a wall face by employing a mounting hardware  33  as shown in FIGS. 5A and 5B. The mounting hardware  33  has a protruded part  33   a  adapted to be engaged with the detecting hole  32   c  when the casing  30  is mounted, and hooks  33   b  to be hooked with the mounting holes  32   d.    
     [0055] Referring to FIGS. 3A, 3B,  4 A,  4 B and  4 C, the following explains the belt  31  which constitutes an essential part of the movable part locking device for the precision appliance.  
     [0056] As shown in FIGS. 3A and 3B, the belt  31  is made of resin having flexibility, for example. The belt  31  is formed of a fixed portion  31   a  fixed to the casing  30 , an abutted portion  31   b  abutted against a side face of the tilt stage  11 , a shift portion  31   c  which is bent when the tilt stage  11  has been locked and straightened when the lock has been released, a fixed portion  31   d  fixed to the back cover  32 , and joint portions respectively connecting these portions.  
     [0057] A shape of the abutted portion  31   b  is determined in a manner that a contact angle with the lock part  11   c  of the tilt stage  11  and moving directions of the belt  31  may not be large. The shift portion  31   c  is provided with a notch  31   e  engaged with the guide part  10  provided on the fixed plate  10  so as to guide the belt  31 .  
     [0058] The fixed portion  31   d  has structure for exerting a force in a direction expanding outwardly at its terminal end by bending 90 degrees like a crest at the joint portion, and thereafter bending 180 degrees like a trough. When the fixed portion  31   d  in a state bended like a trough has been inserted into a wider area of the convex-shaped hole of either the releasing hole  32   a  or the locking hole  32   b,  the fixed portion  31   d  is caught by a narrow area of the convex-shaped hole of the releasing hole  32   a  or the locking hole  32   b  with a repulsive force of the belt  31  which is recovering to the original state. Therefore, the fixed portion  31   d  is not be disengaged.  
     [0059] Further, each of the joint portions connecting the respective portions has a recess in a shape of an inverted triangle, as shown in FIGS. 4A and 4B in an enlarged scale. Open angle are determined θ1 or θ2 to be able to restrict a direction and an angle in which the belt  31  is bent. Small projections may be provided at edges of the recess as shown in FIG. 4C, so that a repulsive force may be generated at the joint portion when the belt has been bended.  
     [0060] On occasion of using the belt  31 , the fixed portion  31   a  is fixed to the casing  30  by a screw or the like, the abutted portion  31   b  extends around a lower part of the lock part  11   c  of the tilt stage  11 , the shift portion  31   c  engages with the guide part  10   a  of the fixed plate  10 , and the fixed portion  31   d  passes through the through hole  10   c  of the fixed plate  10  to be exposed out of the back face of the back cover  32 , and fixed in the releasing hole  32   a  or the locking hole  32   b.    
     [0061] The following, referring to FIGS. 5A and 5B, explains operation of the movable part locking device of the first embodiment having the above-described structure. FIG. 5A is a sectional view showing state that the lock of the tilt stage  11  which is the movable part has been released. FIG. 5B is a sectional view showing state that the tilt stage  11  is locked.  
     [0062] To release the tilt stage  11  which is locked as shown in FIG. 5B, an operator, at first, pushes the fixed portion  31   d  of the belt  31  with a finger. As a result, the fixed portion  31   d  restores to the original state by a repulsive force and fixes in the releasing hole  32   a.  At this time, since the force is exerted in a direction that the belt  31  shifts toward a front face side of the casing  30   as  a whole, the belt  31  is guided along the guide part  10   a  by way of the through hole  10   c  so as to slide in a forward direction. Accordingly, the abutted portion  31   b  shifts toward a front face side of the casing  30 . Therefore, there will be created a gap between the lock part  11   c  of the tilt stage  11  and the abutted portion  31   b,  and the tilt stage  11  become free to rotate.  
     [0063] To lock the tilt stage  11  which is released as shown in FIG. 5A, the operator disengages the fixed portion  31   d  of the belt  31  from the releasing hole  32   a,  and pulls toward the back face side of the back cover  32 . Then, the shift portion  31   c  which was straightened is also pulled backward, and guided by the guide part  10   a  so as to slide in a backward direction. As the abutted portion  31   b  of the belt  31  is also pulled backward, either of the faces of the lock part  11   c  is abutted against the abutted portion  31   b,  irrespective of the condition of the tilt stage  11 . When an operator further pulls the belt  31 , the guide part  10   a  strikes a sectional face of the notch  31   e  of the shift portion  31   c  to function as a stopper.  
     [0064] Then, the operator bends the joint portion in the shift portion  31   c  of the belt  31  to an outside of the back cover  32 . Thereafter, the operator collapses the fixed portion  31   d  insert into the locking hole  32   b  to make free. Then, the fixed portion  31   d  is restored to the original state with the repulsive force and fixed in the locking hole  32   b.  On this occasion, since the lock part  11   c  of the tilt stage  11  and the abutted portion  31   b  are in tight contact with each other, the tilt stage  11  become unable to rotate in a downwardly inclined fixed state.  
     [0065] The following, referring to FIGS. 5A and 5B, explains operation of installing the casing  30  containing the iris image pickup apparatus to the mounting hardware  33  which was mounted on a wall. As described before, the mounting hardware  33  has the protruded part  33   a  protruded in an opposite direction to the wall face, and the two hooks  33   b  in the upper part.  
     [0066] In the state that the tilt stage  11  is released by the belt  31  as shown in FIG. 5A, an operator presses the casing  30  against the wall face, while position of the protruded part  33   a  of the mounting hardware  33  with respect to the detecting hole  32   c  of the back cover  32 , and position of the hooks  33   b  with respect to the mounting holes  32   d  are respectively aligned. Thereafter, the operator slides the casing  30  downward, then, the hooks  33   b  of the mounting hardware  33  come into engagement with the mounting holes  32   d  of the back cover  32  to secure the casing  30 .  
     [0067] On the other hand, in the state that the tilt stage  11  is locked by the belt  31  as shown in FIG. 5B, the detecting hole  32   c  of the back cover  32  is blocked with the belt  31  as described before. Therefore, even though an operator try to mount the casing  30  on the mounting hardware  33 , the operator cannot insert the protruded part  33   a  of the mounting hardware  33  into the detecting hole  32   c.  Thus, the operator can quickly learn that the tilt stage  11  is locked. The camera appliances such as the iris image pickup apparatus are essentially unable to perform their function, unless the lock of the tilt stage  11  is released. Consequently, it is possible to effectively prevent the apparatus from being mounted on the mounting hardware  33  without releasing the lock, by mistake.  
     [0068] Such function can be also performed by providing the fixed portion  31  of the belt  31  or other means, for example, a screw, so as to project outwardly from the back cover  32  when the tilt stage  11  is locked. On the other hand, The function can be also performed by providing the fixed portion  31   d  of the belt  31  or a head of the screw so as to be positioned inside a face of the back cover  32  when the lock of the tilt stage is released.  
     [0069] In the state that the tilt stage  11  is released by the belt  31  as shown in FIG. 5A, when the operator tries to mount the casing  30  to the mounting hardware  33 , there is no obstacle for mounting the casing  30  to the mounting hardware  33 . The reason is that the fixed portion  31   d  of the belt  31  is inserted into the releasing hole  32   a  positioned inside the face of the back cover  32 .  
     [0070] On the other hand, in a state that the tilt stage  11  is locked by the belt  31  as shown in FIG. 5B, even if the operator tries to mount the casing  30  to the mounting hardware  33 , the fixed portion  31   d  will protrude out of the face of the back cover  32  and come into abutment against the mounting hardware  33 . The reason is that the fixed portion  31 d of the belt  31  or the head of the screw is inserted into the locking hole  32   b  which is on the same plane as the back cover  32 . Accordingly, the casing  30  is unable to be mounted on the mounting hardware  33 , thus, it is possible to prevent the apparatus from being mounted on the mounting hardware  33 , without releasing the lock of the movable part such as the tilt stage  11 , by mistake.  
     [0071] In the case that the operator forcibly tries to push the belt  31  deep into the casing  30  by mistake, the shift portion  31   c  of the belt  31  is pushed upwardly from the through hole  10   c  of the fixed plate  10 . After the shift portion  31   c  has been pushed in to a certain extent, the shift portion  31   c  comes into contact with the guide part  32   e  which is usually not in a position to touch with the belt  31 , and prevented from being further inserted. Therefore, the belt  31  does not disturb the rotation of the tilt stage  11  inside the casing  30 .  
     [0072] As described above, the tilt stage  11  of the iris image pickup apparatus can be reliably held and locked, by abutting the belt  31  fixed at its one end to the casing  30  against the lock part  11   c  constituting a part of the tilt stage  11 , and further, by inserting the other end of the belt  31  into the locking hole  32   b  of the back cover  32 .  
     [0073] Moreover, when the other end of the belt  31  is disengaged from the locking hole  32   b  and inserted into the releasing hole  32   a,  the tilt stage  11  become free to rotate. Therefore, the operator can easily know whether the tilt stage  11  as a movable part is in the locked state or in the released state, at a glance over the position where the belt  31  is inserted.  
     [0074] Further, because the other end of the belt  31  is fixed to the back cover  32  at different positions depending on the occasion when the tilt stage  11  has been locked or released, it is be possible to prevent the apparatus from being mounted on the mounting hardware  33 , without releasing the lock, by mistake.  
     [0075] Still further, because the back cover  32  is independent of the fixed plate  10 , the through hole  10   c  of the fixed plate  10  can be made sufficiently large to incorporate the guide part  32   e  provided on the back cover  32  behind the through hole  10   c.  Accordingly, the belt  31  can be easily passed close to the locking hole  32   b,  and operability enhances.  
     [0076] (Second Embodiment)  
     [0077]FIG. 6A is a plain view of the belt of a second embodiment. FIG. 6B is a side view of the belt of a second embodiment. FIG. 7 is a perspective view showing a structure of the back cover of the second embodiment. FIG. 8A is a sectional view showing lock-released state of the movable part locking device of the second embodiment. FIG. 8B is a sectional view showing locked state of the movable part locking device of the second embodiment.  
     [0078] The second embodiment is not different in function from the first embodiment. However, the other end  31   d  of the belt  31  is fixed by means of a screw in the second embodiment, which can be preferably applied to a case in which there is a space behind the back cover. The second embodiment is described hereunder, referring to FIG. 6A to FIG. 8B. It is to be noted that the components which are common with those components in FIGS. 2, 3A,  3 B,  5 A and  5 B will be denoted with same reference numerals, and their explanation is omitted.  
     [0079]FIGS. 6A and 6B are structural view showing a shape of the belt for locking the tilt stage  11  to be employed in this embodiment, which are different from FIGS. 3A and 3B in the shape of the fixed portion. The belt  41  is made of resin, for example, having flexibility. The belt  41  is constructed to have a fixed portion  41   a  fixed to the casing  30 , an abutted portion  41   b  abutted against a side face of the tilt stage  11 , a shift portion  41   c  which is bent when the tilt stage  11  has been locked and straightened when the lock has been released, a fixed portion  41   d  having at its end a round hole  41   f  to be fixed to the back cover  42 , and joint portions respectively connecting these portions.  
     [0080] As shown in FIG. 7, the back cover  42  has a face erected backward by cutting from a portion of its rightward lower part, which is provided with a releasing hole  42   a  formed with screw hole for fixing the fixed portion  41   d  of the belt  41 , which will be described below, when the lock of the tilt stage  11  is released. Above the releasing hole  42   a,  there is further provided a locking hole  42   b  formed with screw hole for fixing the fixed portion  41   d  of the belt  41 , which will be described below, when the tilt stage  11  is locked.  
     [0081] Referring to FIGS. 8A and 8B, the following explains operation of the movable part locking device according to the second embodiment having the above described structure. FIGS. 8A and 8B are view showing the mode of operation of the movable part locking device. FIG. 8A shows a state that the lock of the tilt stage  11  as the movable part has been released. FIG. 8B shows a state that the tilt stage  11  is locked.  
     [0082] To release the tilt stage  11  which is locked as shown in FIG. 8B, an operator secures by a screw the fixed portion  41   d  of the belt  41  into the releasing hole  42   a  of the back cover  42  through the round hole  41   f.  Following this movement, a forwardly pushing force is exerted on the belt  41 , and the shift portion  41   c  is expanded. In the same manner as described in the first embodiment, there will be created a gap between the lock part  11   c  of the tilt stage  11  and the abutted portion  41   b,  and the tilt stage  11  become free to rotate.  
     [0083] To lock the tilt stage  11  which is unlocked as shown in FIG. 8A, the operator disengages the screw which secured the fixed portion  41   d  of the belt  41  from the releasing hole  42   a,  and pulls to the back face side of the back cover  42 . With this motion, the shift portion  41   c  and the abutted portion  41   b  are also pulled backward. As the results, the lock part  11   c  of the tilt stage  11  comes into abutment against the abutted portion  41   b.    
     [0084] Then, the operator upwardly bends the joint portion in the shift portion  41   c  of the belt  41  to an outside of the back cover  42 . Thereafter, the operator secures by the screw the fixed portion  41   d  of the belt  41  in the locking hole  42   b  through the round hole  41   f.  On this occasion, since the lock part  11   c  of the tilt stage  11  and the abutted portion  41   b  are in tight contact with each other, the tilt stage  11  become unable to rotate in a downwardly inclined fixed state.  
     [0085] As described above, when the tilt stage  11  has been locked, the screw is projected outward of the back cover  42 . Accordingly, the casing  30  is unable to be mounted on the mounting hardware  33 . On the other hand, when the tilt stage  11  which was locked has been released, the belt  41  is secured to the face which is erected by cutting inwardly of the back cover  42 , and the screw head sinks inside the back face of the back cover  42 . As the results, the casing  30  can be mounted on the mounting hardware  33  without a problem. In this manner, the operator can easily recognize that the tilt stage  11  is locked.  
     [0086] It is to be noted that although the illuminating units  15 ,  16  for the telephoto cameras are mounted on the tilt stage  11  in the above described embodiments, substantially the same operation and effects as in the above described embodiments can be obtained, even in case that they are arranged outside. It is also possible to omit the panning mirror  13  and the panning motor  14  which drives the panning mirror  13 , and to render the telephoto camera  12  to directly pan.  
     [0087] Moreover, although it is so constructed that the notch in the shift portion  31   c  ( 41   c ) of the belt  31  ( 41 ) is clamped by the two upright guide parts  10   a  of the fixed plate  10  so as to be guided, it is possible to form an elongated hole in a middle of the shift portion  31   c  ( 41   c ) so as to guide the belt by a single guide part  10   a.    
     [0088] Further, although these embodiments have been so far described referring to the tilt stage of the iris image pickup apparatus as an example of the movable part of the precision appliance, the invention can be widely applied to apparatuses such as the precision appliance having the movable member contained in a casing.