Patent Document

TECHNICAL FIELD  
       [0001]     The present invention relates to a photographing apparatus such as a monitoring camera apparatus or a video camera apparatus, and more particularly, to a pickup device driving apparatus for moving a pickup device in an optical axis direction of a lens and a photographing apparatus using the same.  
       BACKGROUND ART  
       [0002]     Conventionally, in order to perform flange focus adjustment or focus adjustment, a photographing apparatus for automatically moving a pickup device in an optical axis direction of a lens using a driving part such as a motor to obtain a clear image is suggested (for example, Japanese Patent Unexamined Publication No. 2003-274229).  
         [0003]     In such a photographing apparatus, a lead screw is used for moving a pickup device, the pickup device is attached to a nut which is rotatably provided relative to the lead screw, and the lead screw rotates by a stepping motor. By this configuration, the lead screw rotates by rotation of the stepping motor and thus the pickup device can be moved by a desired distance in the optical axis direction of the lens.  
         [0004]     However, in such a photographing apparatus, when photographing is performed in a state that the photographing apparatus is inclined, driving due to the driving part is interrupted by the weight of a member such as the pickup device or a peripheral circuit part. More specifically, for example, in the above-described conventional technology, when photographing is performed in a state that the photographing apparatus is inclined such that a photographing direction becomes an upward direction or a downward direction, an oblique biasing force is generated between the lead screw and the nut provided with the pickup device, due to the weight of the member such as the pickup device or the like. When the driving part has no a sufficient force, the lead screw cannot smoothly rotate due to the biasing force. As a result, the pickup device cannot be adequately driven.  
       DISCLOSURE OF THE INVENTION  
       [0005]     The present invention has been made in view of the above problem and provides a pickup device driving apparatus which is capable of adequately driving a pickup device even when photographing is performed in a state that a photographing apparatus is inclined such that a photographing direction becomes an upward direction or a downward direction, and a photographing apparatus using the same.  
         [0006]     According to an aspect of the present invention, there is provided a pickup device driving apparatus including a movable part which has a pickup device and is capable of moving the pickup device in a first direction while a direction of a pickup surface is held; a driving part which has an axis part and is capable of moving the axis part in a second direction different from the first direction such that the movable part is moved; a direction changing part which is in contact with the axis part of the driving part and the movable part, has a rotation axis part provided in a third direction perpendicular to the first direction and the second direction, rotates on the rotation axis part, changes a bias force applied in the second direction by the axis part of the driving part to a bias force applied in the first direction, and applies the bias force to the movable part to move the movable part; and a weight part which is provided in the direction changing part to generate a rotation moment which cancels a rotation moment of the rotation axis part generated in the direction chan ging part by the inclination of the movable part.  
         [0007]     By this configuration, since the movement direction of the movable part having the pickup device and the movement direction of the axis part of the driving part are different from each other and the direction changing part having the rotation axis part rotates, the direction of the bias force applied by the driving part can be changed to be transferred to the movable part. In addition, since the weight part which cancels the rotation moment generated in the direction changing part by the weight of the movable part is included in the direction changing part, even when the photographing apparatus is inclined such that a photographing direction becomes an upward direction or a downward direction, the rotation moment generated in the direction changing part is cancelled. Accordingly, it is possible to provide a pickup device driving apparatus capable of adequately driving the pickup device.  
         [0008]     The direction changing part may include a first contact part which is in contact with the axis part of the driving part and a second contact part which is in contact with the movable part, and the weight part may be provided at the side opposite to the side of the direction changing part having the second contact part with respect to the rotation axis part.  
         [0009]     By this configuration, since the weight part is provided at the side opposite to the side of the direction changing part having the second contact part, which is in contact with the movable part, with respect to the rotation axis part, it is possible to realize a configuration for more easily canceling the rotation moment generated in the direction changing part when the photographing apparatus is inclined.  
         [0010]     A holding member for attaching the weight part may be provided at the side opposite to the side of the direction changing part having the second contact part with respect to the rotation axis part.  
         [0011]     By this configuration, since the holding member is further included, the weight part is easily attached and the length from the rotation axis part to the weight part can be easily adjusted.  
         [0012]     An elastic member for applying an elastic force to the direction changing part in an opposite direction of the bias force applied by the axis part of the driving part may be further included.  
         [0013]     By this configuration, since the bias force applied by the axis part of the driving part is smoothly transferred to the direction changing part, the pickup device can be more smoothly moved.  
         [0014]     When the weight of the movable part is W 1 , the weight of the weight part is W 2 , a distance between the center of the rotation axis part and a position in which the second contact part and the movable part are in contact with each other, and a distance between the center of the rotation axis part and the gravity center of the weight part, a relationship of W 1 ×L 1 =W 2 ×L 2  may be satisfied.  
         [0015]     By this configuration, when the photographing apparatus is inclined such that the photographing direction becomes the upward direction or the downward direction, the rotation moment generated in the direction changing part can be most efficiently cancelled.  
         [0016]     The pickup device driving apparatus may further include a base part fixed to a lens part; a first support part and a second support part which are provided between the base part and the movable part facing the base part to support the movable part; a first rotating part which is provided between the base part and the first support part; a second rotating part which is provided parallel to the first rotating part in the optical axis direction, between the base part and the second support part; a third rotating part which is provided between the movable part and the first support part; and a fourth rotating part which is provided at an apex of a parallelogram with respect to the first rotating part, the second rotating part and the third rotating part, between the movable part and the second support part, wherein the rotating central axes of the first rotating part, the second rotating part, the third rotating part and the fourth rotating part may be perpendicular to the first direction and parallel to one another, and the position of the pickup device may be changed relative to the lens part in a state that the first rotating part, the second rotating part, the third rotating part and the fourth rotating part form the apexes of the parallelogram by driving of the driving part.  
         [0017]     By this configuration, since the movable part includes four rotating parts of which the rotation axes are perpendicular to the first direction and one side is provided at the apex of the parallelogram parallel to the first direction, the pickup device can be moved in the optical axis direction of the lens part while the pickup surface is held in a predetermined direction by a simple configuration that the pickup device is attached to the movable part in a state that the pickup surface is directed in the predetermined direction. Accordingly, a possibility that mechanical rattle using the lead screw and the nut is generated is reduced, and, even when the pickup device is moved by a slight distance, it is possible to realize a pickup device driving apparatus having high precision.  
         [0018]     At least one of the first rotating part, the second rotating part, the third rotating part and the fourth rotating part may be a leaf spring.  
         [0019]     By this configuration, since mechanical rattle or friction is not generated in the leaf spring of the rotating parts connected to the members, hysteresis can be suppressed from being generated and driving precision can be improved.  
         [0020]     The first rotating part, the second rotating part, the third rotating part and the fourth rotating part may be leaf springs.  
         [0021]     By this configuration, since the rotating part connected to the members are leaf springs, mechanical rattle or friction is not generated, hysteresis can be suppressed from being generated, and driving precision can be improved.  
         [0022]     The movable part, the first support part, the second support part and the leaf spring may be integrally formed and at least one of the movable part, the first support part and the second support part may have a reinforcement part for increasing rigidity.  
         [0023]     By this configuration, since the movable part, the first support part, the second support part and the leaf spring can be manufactured by an integral member, a simple configuration can be realized. In addition, since at least one of the first support part and the second support part has the reinforcement part, a configuration having necessary rigidity can be realized.  
         [0024]     A heat radiation part for radiating heat generated in the vicinity of the pickup device may be provided in the movable part.  
         [0025]     By this configuration, since it is possible to allow heat generated in the vicinity of the pickup device to escape by radiation of the heat radiation part, it is possible to allow heat generated in the vicinity of the pickup device to escape without generating a frictional force even when a pickup device is moved in an optical axial direction.  
         [0026]     The heat radiation part may be provided to face a heat sink part provided in a case.  
         [0027]     According to this configuration, it is possible to allow heat to escape by radiation from the heat radiation part of the pickup device driving apparatus to the heat sink part provided in the case.  
         [0028]     Convex parts may be provided on a surface of the heat radiation part facing the heat sink part.  
         [0029]     By this configuration, since a heat radiation area increases, it is possible to increase radiation efficiency.  
         [0030]     The convex parts of the heat radiation part may be provided to face concave parts of irregularities provided in the heat sink part.  
         [0031]     By this configuration, since a facing area between the heat radiation part and the heat sink part increases, it is possible to increase radiation efficiency.  
         [0032]     The convex parts of the heat radiation part may have fin which extends in a movement direction of the pickup device.  
         [0033]     By this configuration, although the pickup device is moved, the heat radiation part is hard to come in contact with the heat sink part and thus radiation efficiency can increase.  
         [0034]     The heat radiation part may not be in contact with the heat sink part within a movement range of the pickup device.  
         [0035]     By this configuration, although the pickup device is moved, the heat sink part does not come in contact with the heat radiation part. Accordingly, it is possible to realize a configuration which can smoothly move the pickup device.  
         [0036]     According to another aspect of the present invention, there is provided a photographing apparatus including a lens part; a case; the pickup device driving apparatus of the present invention; and an image signal processing part which performs an image signal process on a signal output from the pickup device of the pickup device driving apparatus.  
         [0037]     By this configuration, since the movement direction of the movable part having the pickup device and the movement direction of the axis part of the driving part are different from each other and the direction changing part having the rotation axis part rotates, the direction of the bias force applied by the driving part can be changed to be transferred to the movable part. In addition, since the weight part which cancels the rotation moment generated in the direction changing part by the weight of the movable part is included in the direction changing part, even when the photographing apparatus is inclined such that a photographing direction becomes an upward direction or a downward direction, the rotation moment generated in the direction changing part is cancelled. Accordingly, it is possible to provide a photographing apparatus capable of adequately driving the pickup device.  
         [0038]     According to another aspect of the present invention, there is provided a monitoring camera apparatus including the photographing apparatus of the present invention; an illumination-intensity change detecting part which detects change in illumination intensity; a filter part which attaches and detaches an infrared cut filter on an optical axis of the lens part depending on the change in illumination intensity detected by the illumination-intensity change detecting part; and a filter driving part which drives the movable part of the pickup device driving apparatus when the infrared cut filter of the filter part is attached and detached.  
         [0039]     By this configuration, since the pickup device can be moved in the optical axis direction of the lens part in a state that the pickup surface is held in a predetermined direction with respect to the optical axis direction of the lens part when the infrared cut filter is attached and detached, displacement in a optical path length can be corrected when the infrared cut filter is attached and detached. Accordingly, it is possible to provide a monitoring camera apparatus capable of performing photographing with high precision day and night. Since the movement direction of the movable part having the pickup device and the movement direction of the axis part of the driving part are different from each other and the direction changing part having the rotation axis part rotates, the direction of the bias force applied by the driving part can be changed to be transferred to the movable part. In addition, since the weight part which cancels the rotation moment generated in the direction changing part by the weight of the movable part is included in the direction changing part, even when the photographing apparatus is inclined such that a photographing direction becomes an upward direction or a downward direction, the rotation moment generated in the direction changing part is cancelled. Accordingly, it is possible to provide a monitoring camera apparatus capable of adequately driving the pickup device.  
         [0040]     As described above, according to the present invention, it is possible to provide a pickup device driving apparatus which is capable of adequately driving a pickup device even when photographing is performed in a state that a photographing apparatus is inclined such that a photographing direction becomes an upward direction or a downward direction, and a photographing apparatus using the same. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0041]      FIG. 1  is an exploded perspective view showing a configuration of photographing apparatus according to an embodiment of the present invention;  
         [0042]      FIG. 2  is a view showing a positional relationship among a base attaching part, a pickup device driving apparatus, and a heat sink part when the photographing apparatus according to the embodiment of the present invention is used;  
         [0043]      FIG. 3  is a cross-sectional view showing the positional relationship among the base attaching part, the pickup device driving apparatus, and the heat sink part in the photographing apparatus according to the embodiment of the present invention;  
         [0044]      FIG. 4  is a view showing a positional relationship between a heat radiation part and a heat sink part in the photographing apparatus according to the embodiment of the present invention;  
         [0045]      FIG. 5  is a perspective view showing a configuration of a pickup device driving apparatus according an embodiment of the present invention;  
         [0046]      FIG. 6  is a side view showing the configuration of the pickup device driving apparatus according to the embodiment of the present invention;  
         [0047]      FIG. 7  is an exploded perspective view showing the pickup device driving apparatus according to the embodiment of the present invention when viewed from the opposite side of a lens part;  
         [0048]      FIG. 8A  is a plan view showing a configuration of a driving part in the pickup device driving apparatus according to the embodiment of the present invention;  
         [0049]      FIG. 8B  is a plan view showing a configuration of the driving part in the pickup device driving apparatus according to the embodiment of the present invention;  
         [0050]      FIG. 9A  is a view explaining an operation of the pickup device driving apparatus according to the embodiment of the present invention;  
         [0051]      FIG. 9B  is a view explaining the operation of the pickup device driving apparatus according to the embodiment of the present invention;  
         [0052]      FIG. 10A  is a view showing a balance member mounted on the pickup device driving apparatus of the photographing apparatus according to the embodiment of the present invention;  
         [0053]      FIG. 10B  is a view showing the balance member mounted on the pickup device driving apparatus of the photographing apparatus according to the embodiment of the present invention;  
         [0054]      FIG. 11A  is a view showing another example of the balance member mounted on the pickup device driving apparatus of the photographing apparatus according to the embodiment of the present invention;  
         [0055]      FIG. 11B  is a view showing another example of the balance member mounted on the pickup device driving apparatus of the photographing apparatus according to the embodiment of the present invention; and  
         [0056]      FIG. 12  is a view showing another example of the pickup device driving apparatus and the photographing apparatus according to the embodiment of the present invention.  
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0057]     Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings.  
       Embodiment  
       [0058]     First, a configuration of photographing apparatus  1  according to an embodiment of the present invention will be described.  FIG. 1  is an exploded perspective view showing a configuration of photographing apparatus  1  according to the embodiment of the present invention.  
         [0059]     For simplification of description, in the embodiment of the present invention, an X axis direction, a Y axis direction and a Z axis direction perpendicular to one another are shown in the drawings. The X axis direction is an optical axis direction of a lens part, and the Y axis and Z axis direction are perpendicular to the optical axis direction. In the embodiment of the present invention, for understanding of description, detailed parts such as screw or the like will be omitted in the drawings.  
         [0060]     As shown in  FIG. 1 , photographing apparatus  1  according to the embodiment of the present invention includes lens mounting part  2  attached with lens part  101 , base attaching part  3  for connecting base  6  of pickup device driving apparatus  70  to lens mounting part  2 , DC motor part  4 , that is, a filter driving part, which is disposed on base attaching part  3  and moves below-described filter part  5  in a direction (Y axis direction) perpendicular to the optical axis direction, filter part  5  which is attached to DC motor part  4  and has an infrared cut filter (not shown) which can be moved in the Y axis direction by driving DC motor part  4 , pickup device driving apparatus  70  which is attached to base attaching part  3 , has heat radiation part  120  including convex parts  121 , which has a fin shape and extends in the X axis direction, and can move pickup device (known pickup device such as CCD or CMOS sensor)  15  in a state that pickup surface  83  is perpendicular to the optical axis direction of lens part  101 , heat sink part  140  which is provided such that convex parts  141  provided at one end thereof face concave parts between convex parts  121  of heat radiation part  120  of pickup device driving apparatus  70  and of which the other end has a comb-like fin and is air-cooled by fan motor  130  which is a cooling means, and attaching member  150  attached with heat sink part  140  and fixed to lens mounting part  2 . In addition, the photographing apparatus  1  according to the embodiment of the present invention includes an image signal processing part (not shown) for performing an image signal process on a signal output from pickup device  15 .  
         [0061]     The configuration and operation of pickup device driving apparatus  70  mounted on photographing apparatus  1  according to the embodiment of the present invention will be described.  
         [0062]     In the embodiment of the present invention, heat radiation part  120  and heat sink part  140  were obtained by die-casting aluminum and coating black alumite on the. surface thereof to improve radiation efficiency. Convex parts  121  and  141  which extend in the optical axis direction of lens part  101  and have a width of 1.0 mm and a height of  3 . 5  mm are provided on the surface of heat radiation part  120  which faces heat sink part  140  (upper surface of  FIG. 1 ) and the surface of heat sink part  140  which faces heat radiation part  120  (lower surface of  FIG. 1 ), respectively.  
         [0063]      FIG. 2  is a view showing a positional relationship among base attaching part  3 , pickup device driving apparatus  70 , and heat sink part  140  when photographing apparatus  1  according to the embodiment of the present invention is used.  FIG. 3  is a cross-sectional view showing the positional relationship among base attaching part  3 , pickup device driving apparatus  70 , and heat sink part  140  in photographing apparatus  1  according to the embodiment of the present invention. As shown in  FIGS. 2 and 3 , in photographing apparatus  1  according to the embodiment of the present invention, heat generated at pickup device  15  or peripheral driving circuit upon the usage is transferred to pickup device holding part  11  and heat radiation part  120 . Thereafter, the heat is transferred to one end of heat sink part  140  by radiation of heat radiation part  120  through an air layer. At this time, in photographing apparatus  1  according to the embodiment of the present invention, since the other end of heat sink part  140  is cooled by fan motor  130 , it is possible to suppress a temperature of pickup device  15  from rising. In photographing apparatus  1  according to the embodiment of the present invention, a comb-like fin is provided at the other end of heat sink part  140  in order to efficiently allow wind caused by fan motor  130  to flow at the other end or to improve radiation efficiency by increasing a contact area of heat sink part  140  for wind.  
         [0064]     As shown in  FIG. 2  or  FIG. 3 , in photographing apparatus  1  according to the embodiment of the present invention, heat radiation part  120  provided in pickup device driving apparatus  70  and heat sink part  140  attached to attaching member  150  fixed to lens mounting part  2  are provided such that convex parts  121  and  141  are alternately disposed, that is, irregularities provided in the surface of heat radiation part  120  and irregularities provided in surface of heat sink part  140  are engaged with each other while being spaced apart from each other. That is, convex parts  121  of heat radiation part  120  are disposed between convex part  141  of heat sink part  140  and convex parts  141  of heat sink part  140  are disposed between convex parts  121  of heat radiation part  120 .  
         [0065]      FIG. 4  is a view showing a positional relationship between heat radiation part  120  and heat sink part  140  in photographing apparatus  1  according to the embodiment of the present invention. As shown in  FIG. 4 , a front end of convex part  121  of heat radiation part  120  is spaced apart from flat part  142  of heat sink part  140  by gap Δ 1  of about 0.5 mm, interval γ between convex part  121  of heat radiation part  120  and convex part  141  of heat sink part  140  is about 0.5 mm, and a front end of convex part  141  of heat sink part  140  is spaced apart from flat part  122  of heat radiation part  120  by gap Δ 2  of about 1.0 mm. As described above, width α of convex part  141  of heat sink part  140  is 1.0 mm and width β of convex part  121  of heat radiation part  120  is 1.0 mm.  
         [0066]     As shown in  FIG. 3 , in photographing apparatus  1  according to a first embodiment of the present invention, since base  6  of pickup device driving apparatus  70  is attached to base attaching part  3  and base attaching part  3  is threadably fixed to lens mounting part  2 , heat radiation part  120  provided in pickup device driving apparatus  70  is positioned relative to lens mounting part  2 . Since heat sink part  140  is attached to attaching member  150  and attaching member  150  is attached to lens mounting part  2 , heat sink part  140  is also positioned relative to lens mounting part  2 . Accordingly, in photographing apparatus  1  according to the embodiment of the present invention, the interval between heat radiation part  120  and heat sink part  140  can be accurately determined.  
         [0067]     In order to confirm an effect that the temperature is suppressed from rising due to radiation of photographing apparatus  1  according to the embodiment of the present invention, three experiments were performed as follows:  
         [0068]     (1) in a case where heat radiation part  120  was provided, heat sink part  140  was not provided, and heat in the vicinity of pickup device  15  was radiated into a case.  
         [0069]     (2) in a case where heat radiation part  120  and heat sink part  140  were provided, and heat in the vicinity of pickup device  15  was radiated from heat radiation part  120  to heat sink part  140 .  
         [0070]     (3) in a case where heat radiation part  120  and heat sink part  140  were provided and the other end of heat sink part  140  is cooled by fan motor  130  such that heat in the vicinity of pickup device  15  is radiated,  
         [0071]     maximum values of the temperature in the vicinity of pickup device  15  were measured in a state that a heating value of 452 mW is generated in the vicinity of pickup device  15 .  
         [0072]     As a result, in the case (1), the temperature rises by about 9.8 degrees at the rear surface of pickup device  15 . In the case (2), the temperature rises by about 8.6 degrees. In case (3), the temperature rises by about 5.9 degrees.  
         [0073]     That is, it can be seen that, by providing heat sink part  140 , heat sink efficiency is improved by about 10% and, by cooling the other end of heat sink part  140  using fan motor  130 , heat sink efficiency is improved by about 40%, compared with a configuration without heat sink part  140 .  
         [0074]     Photographing apparatus  1  according to the embodiment of the present invention is a monitoring camera apparatus which performs photographing while switching filter part  5  according to brightness of an environment day and night. In other words, in a bright environment, the infrared cut filter is disposed on the optical axis and color image photographing is performed in a visible light area, and in a dark environment, the infrared cut filter disposed on the optical axis is removed and monochromic image photographing is performed by light beam having a wavelength including infrared light area. In photographing device  1 , the brightness of the environment can be detected by comparing illumination intensity detected by illumination-intensity detecting part (not shown) mounted in a circuit part (not shown) with a predetermined threshold value. When the illumination intensity detected by the illumination-intensity detecting part is changed to exceed the predetermined threshold value, it is determined that transition from daytime to nighttime occurs. Thus, the circuit part switches filter part  5 . In addition, the switching of filter part  5  can be performed by DC motor part  4  attached to base attaching part  3 .  
         [0075]     In photographing apparatus  1  according to the embodiment of the present invention, the switching of filter part  5  is performed when the illumination intensity is changed. At this time, since the infrared cut filter is disposed or detached (hereinafter, referred to as attached/detached) on the optical axis or the wavelength of the light beam used for photographing varies, the optical path length is changed and thus an optimal focusing position from lens part  101  to a surface (hereinafter, referred to as pickup surface  83 ) on which a photoelectric converting element is disposed in pickup device  15  is changed. In order to correct change in optical path length, in photographing device  1  according to the embodiment of the present invention, pickup device driving apparatus  70  for moving pickup device  15  in the optical axis direction (X axis direction) in a state that pickup surface  83  is held in a direction perpendicular to the optical axis direction of lens part  101  (that is, a state that pickup surface  83  is located in a plane parallel to a YZ plane in  FIG. 1 ) is mounted.  
         [0076]     Now, pickup device driving apparatus  70  mounted on pickup device  1  according to the embodiment of the present invention will be described.  
         [0077]      FIG. 5  is a perspective view showing a configuration of pickup device driving apparatus  70  according to an embodiment of the present invention,  FIG. 6  is a side view of the configuration of pickup device driving apparatus  70 , and  FIG. 7  is an exploded perspective view showing pickup device driving apparatus  70  when viewed from the opposite side of lens part  101 . In  FIGS. 5, 6  and  7 , the shapes of some elements are schematically shown in comparison with the configuration shown in  FIG. 1 .  
         [0078]     As shown in  FIG. 5, 6 , or  7 , pickup device driving apparatus  70  according to the embodiment of the present invention includes base  6  which is attached to base attaching part  3  fixed to lens part  101  by screw  71 , first support part  8  and second support part  9  which are mounted on base surface  62  of base  6  in parallel to each other and have the same height in the Y axis direction, rectangular movable part  7  which is attached parallel to base surface  62  in a state that first support part  8  and second support part  9  are placed parallel to each other, leaf springs  10  which are provided between movable part  7  and first support part  8 , between movable part  7  and second support part  9 , between base  6  and first support part  8 , and between base  6  and second support part  9 , reinforcement plate  27  which is attached to the upper surface of movable part  7  by screw  28 , first reinforcement plate  16  which is attached to first support part  8  by screw  24  and reinforces mechanical rigidity of first support part  8 , second reinforcement plate  17  which is attached to second support part  9  by screw  26  and reinforces mechanical rigidity of second support part  9 , pickup device holding part  11  which is attached to the surface (rear surface) opposite to the surface (front surface), on which reinforcement plate  27  of movable part  7  is mounted, by screw  28 , is attached with pickup device circuit part  12  having pickup device  15  through insulating sheet  13  and heat sink plate  14  by screw  25 , and has above-described heat radiation part  120 , pin  29  which is provided on the lower surface facing base surface  62  of pickup device holding part  11 , actuator holding part  81  which is mounted on base surface  62 , linear actuator  20  which is held by actuator holding part  81 , driving direction changing part  22  which is pivotably supported by bearing part  18  mounted on base surface  62  to be rotated in the Y axis direction, leaf spring  19  which is mounted in driving direction changing part  22  and slides pin  29  interposed between driving direction changing part  22  and leaf spring  19 , coil spring  21  which is an elastic member for providing an elastic force to driving direction changing part  22  in the opposite direction of a bias force applied from linear actuator  20 , spring fixing part  30  for holding coil spring  21 , and balance member  220  which is threadably fixed to driving direction changing part  22  by screw  200  and attached with weight  210  by screw  201  in order to hold balance with heat radiation part  120  provided in pickup device holding part  11 .  
         [0079]     When pickup device driving apparatus  70  according to the embodiment of the present invention includes coil spring  21 , driving direction changing part  22  is brought into contact with axis  98  of linear actuator  20  and thus driving direction changing part  22  is smoothly moved. Accordingly, pickup device  15  is smoothly moved in the optical axis direction.  
         [0080]     As shown in  FIG. 5, 6  or  7 , in pickup device driving apparatus  70  according to the embodiment of the present invention, movable part  7 , first support part  8 , second support part  9 , and leaf springs  10  are formed by U-shaped integral member  80  which is subjected to a bending process in a U shape. As a material of U-shaped member  80 , a material having relatively low rigidity such as a SUS material having a thickness of 0.12 mm can be used.  
         [0081]     Base attaching part  3 , base  6 , and pickup device holding part  11  may be manufactured by a die casting method using aluminum.  
         [0082]     As a material of reinforcement plate  27 , first reinforcement plate  16 , and second reinforcement plate  17 , a material having relatively high rigidity such as a SUS material having a thickness of  0 . 5  mm can be used in order to reinforce the mechanical rigidity of U-shaped member  80 .  
         [0083]     In pickup device driving apparatus  70  according to the embodiment of the present invention, first support part  8 , second support part  9 , movable part  7 , and leaf springs  10  are formed by U-shaped integral member  80 . First reinforcement plate  16  and second reinforcement  17  are attached to portions of first support part  8  and second support part  9 , respectively. Bent parts  74  are provided at the sides of first support part  8  and second support part  9 . Thus, rigidity of first support part  8  and second support part  9  is higher than that of leaf springs  10 .  
         [0084]     Bent parts  76  are also provided at portions of movable part  7  of U-shaped member  80 , and reinforcement plate  27  is attached to movable part  7 . Thus, rigidity of movable part  7  is higher than that of leaf springs  10 .  
         [0085]     Bent parts  75  are provided at the ends of attachment surfaces  82  and  85  of U-shaped member  80  to be attached to base surface  62 . Thus, rigidity of this portion can increase.  
         [0086]     Since portions between first support part  8  and second support part  9  and movable part  7  of U-shaped member  80  are not subjected to a reinforcement process such as a bending process and have widths narrower than those of the other portions, these portions function as leaf springs  10 .  
         [0087]     Similarly, since portions between attachment surfaces  82  and  85  of U-shaped member  80  and first support part  8  and second support part  9  are not subjected to a reinforcement process such as a bending process and have widths narrower than those of the other portions, these portions also function as leaf springs  10 .  
         [0088]     In pickup device driving apparatus  70  according to the embodiment of the present invention, attachment surface  82  in which first support part  8  is in contact with base surface  62  and attachment surface  85  in which second support part  9  is in contact with base surface  62  are attached to base surface  62  by screw  71  to be parallel to the Z axis direction perpendicular to the optical axis direction (X axis direction).  
         [0089]     Now, a configuration of driving part  100  of pickup device driving apparatus  70  according to the embodiment of the present invention will be described in detail.  
         [0090]      FIGS. 8A and 8B  are plan views showing a configuration of driving part  100  in pickup device driving apparatus  70  according to the embodiment of the present invention. In  FIG. 8 , balance member  220  having weight  210 , which is included in pickup device driving apparatus  70  of photographing apparatus  1  according to the embodiment of the present invention, is omitted.  
         [0091]     As shown in  FIG. 8A , in pickup device driving apparatus  70  according to the embodiment of the present invention, linear actuator  20  presses driving direction changing part  22  in a downward direction (−Z axis direction) of the drawing by axis  98  which can be moved in a vertical direction (Z axis direction) of the drawing. Coil spring  21  for applying an elastic bias force in the opposite direction of the bias force of linear actuator  20  is mounted on driving direction changing part  22 . One end of coil spring  21  is fixed by spring fixing part  30 . In a state shown in  FIG. 8A , the bias force of linear actuator  20  and the bias force of coil spring  21  are in balance and thus driving direction changing part  22  is in a stop state. Leaf spring  19  is attached to driving direction changing part  22  by screw  99  such that pin  29  of pickup device holding part  11  is interposed between driving direction changing part  22  and leaf spring  19 . Pin  29  slides between driving direction changing part  22  and leaf spring  19  by changing the press force of linear actuator  20 .  
         [0092]      FIG. 8B  shows a state of driving part  100  when the press force of linear actuator  20  increases, in pickup device driving apparatus  70  according to the embodiment of the present invention.  
         [0093]     As shown in  FIG. 8B , when the press force of linear actuator  20  increases in a state shown in  FIG. 8A , that is, when axis  98  extends in the downward direction (−Z axis direction) of the drawing, axis  98  presses driving direction changing part  22  and driving direction changing part  22  rotates on bearing part  18  in a clockwise direction. Thus, pin  29  is moved in a right direction (X axis direction) of the drawing.  
         [0094]     Accordingly, in pickup device driving apparatus  70  according to the embodiment of the present invention, since driving direction changing part  22  for changing an output direction of linear actuator  20  is included in driving part  100 , linear actuator  20  need not be the optical axis direction (X axis direction). Accordingly, linear actuator  20  may be arranged in a direction (Z axis direction) perpendicular to the optical axis direction and thus miniaturization of the apparatus can be realized.  
         [0095]     Now, an operation of pickup device driving apparatus  70  according to the embodiment of the present invention will be described in detail with reference to  FIGS. 9A  to  9 B.  FIGS. 9A and 9B  are views explaining the operation of pickup device driving apparatus  70  according to the embodiment of the present invention. Even in  FIGS. 9A and 9B , balance member  220  having weight  210 , which is included in pickup device driving apparatus  70  of pickup device  1  according to the embodiment of the present invention, is omitted.  
         [0096]      FIG. 9A  is a side view showing an example of the operation of pickup device driving apparatus  70  according to the embodiment of the present invention, and  FIG. 9B  is a side view showing an example when the position of pickup device  15  is changed.  
         [0097]     In  FIG. 9A , first support part  8  and second support part  9  of pickup device driving apparatus  70  are perpendicular to base surface  62 . Distance A 1  between first support part  8  and second support part  9  on base surface  62  is equal to distance A 2  between first support part  8  and second support part  9  at a connection portion with movable part  7  in the optical axis direction (X axis direction). Since height B 1  of first support part  8  from base surface  62  to movable part  7  is equal to height B 2  of second support part  9  from base surface  62  to movable part  7 , movable part  7  is held parallel to base surface  62 . Since base surface  62  is placed parallel to the optical axis direction (X axis direction) of lens part  101 , movable part  7  is also placed parallel to the optical axis direction of lens part  101 .  
         [0098]     In pickup device driving apparatus  70  according to the embodiment of the present invention, pickup device holding part  11  including pickup device circuit part  12  having pickup device  15  is disposed on the lower surface of movable part  7 . At this time, by attaching pickup surface  83  of pickup device  15  to pickup device holding part  11  to be perpendicular to the surface of movable part  7  of pickup device holding part  11 , the pickup surface  83  of pickup device  15  is held perpendicular to the optical axis direction.  
         [0099]     In a state shown in  FIG. 9A , the force of axis  98  of linear actuator  20  for pressing driving direction changing part  22  and the force of coil spring  21  for pressing driving direction changing part  22  in the opposite direction thereof by the elastic force are in balance and pin  29  provided on driving direction changing part  22  is in a stop state, as described in  FIG. 8A . From this state, linear actuator  20  is operated to reduce the bias force applied to driving direction changing part  22 . Then, the force of coil spring  21  for pressing driving direction changing part  22  becomes larger than the force of linear actuator  20  for pressing driving direction changing part  22 , driving direction changing part  22  rotates on bearing part  18 , and pin  29  provided on the front end thereof is moved to the left side of  FIG. 9A . By this movement, pickup device holding part  11  is moved in a left direction (−X axis direction) of the drawing, as shown in  FIG. 9B . Since pickup device holding part  11  is moved in the left direction of the drawing, leaf springs  10  provided between movable part  7  and first support part  8 , between movable part  7  and second support part  9 , between base surface  62  and first support part  8 , and between base surface  62  and second support part  9  are elastically deformed. Accordingly, in pickup device driving apparatus  70  according to the embodiment of the present invention, first support part  8  and second support part  9  rotate on leaf springs  10  (as rotating part), that is, rotate in directions perpendicular to the optical axis direction and parallel to each other, respectively (Z axis direction in  FIGS. 9A and 9B ). Thus, first support part  8  and second support part  9  rotate relative to base  6  and movable part  7 .  
         [0100]     In other words, when pickup device  15  is moved from a state of  FIG. 9A  to a state of  FIG. 9B , since height B, of first support part  8  and height B 2  of second support part  9  are equal to each other and distance A 2  between first support part  8  and second support part  9  at the connection portion with movable part  7  and distance A 1  between first support part  8  and second support part  9  on base surface  62  are equal to each other as described above, movable part  7 , first support part  8 , second support part  9  and base surface  62  are deformed to form a substantial parallelogram. Accordingly, in pickup device driving apparatus  70  according to the embodiment of the present invention, the position of pickup device  15  can be moved in the optical axis direction while movable part  7  is held parallel to base surface  62 . At this time, pickup device  15  is moved in a state that pickup surface  83  of pickup device  15  placed perpendicular to movable part  7  is held in a predetermined direction upon attachment (pickup surface  83  of pickup device  15  is held perpendicular or orthogonal to the optical axis direction).  
         [0101]     In pickup device driving apparatus  70  according to the embodiment of the present invention, contrary to the above, in order to move pickup device  15  to be apart from lens part  101 , by increasing the press force of linear actuator  20 , the bias force applied to driving direction changing part  22  becomes stronger. Then, as shown in  FIG. 8B , the bias force of coil spring  21  for biasing driving direction changing part  22  becomes larger than the bias force of linear actuator  20  for biasing driving direction changing part  22 , driving direction changing part  22  rotates on bearing part  18  in a direction (clockwise direction) opposite to the above, and pin  29  provided on the front end thereof is also moved to the right side of  FIG. 9A . Pickup device holding part  11  is moved in the right direction (X axis direction) by movement of pin  29 .  
         [0102]     In pickup device driving apparatus  70  according to the embodiment of the present invention, since movable part  7  is supported by first support part  8  and second support part  9  which have the same height from base surface  62 , are parallel to each other and rotate in the optical axis direction, movable part  7  can be moved in the optical axis direction while being always held parallel to base surface  62 . Since pickup device holding part  11  is attached such that pickup surface  83  of pickup device  15  is disposed in the direction perpendicular the movable part  7 , pickup device  15  can be moved in the optical axis direction while pickup surface  83  thereof is held perpendicular to the optical axis direction. Thus, pickup device  15  can be moved with high precision.  
         [0103]     In pickup device driving apparatus  70  according to the embodiment of the present invention, mechanisms for moving pickup device  15  in the optical axis direction, that is, mechanisms which include attachment surface  82  contacting with base surface  62 , first support part  8 , movable part  7 , second support part  9 , attachment surface  85 , and leaf springs  10 , can be manufactured by performing processes, such as punching and molding, on an integral plate material. Accordingly, since friction or rattle is extremely low, driving can be performed with high precision even when slight driving is performed.  
         [0104]     Now, balance member  220  having weight  210 , which is included in pickup device driving apparatus  70  of photographing apparatus  1  according to the embodiment of the present invention, will be described in detail.  
         [0105]      FIGS. 10A and 10B  are views showing balance member  220  mounted on pickup device driving apparatus  70  of photographing apparatus  1  according to the embodiment of the present invention.  FIG. 10A  is a plan view showing a peripheral configuration of balance member  220 . In pickup device driving apparatus  70  according to the embodiment of the present invention, balance member  220  is provided in order to reduce a load applied to linear actuator  20  when lens part  101  of pickup device  1  is disposed at the lower side as shown in  FIG. 10B .  
         [0106]     As shown in  FIG. 10A , driving direction changing part  22  includes first contact part  160  which is in contact with axis  98  of linear actuator  20  and second contact part  161  which is in contact with pickup device holding part  11  connected to movable part  7 , and weight  210  is provided at the side opposite to the side of driving direction changing part  22  having second contact part  161  with respect to the bearing part  18 .  
         [0107]     Accordingly, in the state shown in  FIG. 10B , in the vicinity of driving part  100 , downward moment F is generated in the left side of driving direction changing part  22  with respect to bearing part  18 , due to the weight of heat radiation part  120  and pickup device holding part  11 , as shown in  FIG. 10A . Since this moment F rotates driving direction changing part  22  in a counterclockwise direction in  FIG. 10A , in this state, driving direction changing part  22  cannot rotate in a clockwise direction in the same torque as torque applied to linear actuator  20  when photographing apparatus  1  is placed on the horizontal plane of earth. To this end, in photographing apparatus  1  according to the embodiment of the present invention, balance member  220  having weight  210  is provided at the side opposite to the side of driving direction changing part  22  having pin  29  with respect to bearing part  18 . By this configuration, as shown in  FIG. 10A , since a downward force, that is, moment W for rotating driving direction changing part  22  in the clockwise direction can be generated by weight  210 , linear actuator  20  rotates driving direction changing part  22  with the same torque as when photographing apparatus  1  is placed on the plane. The length of the arm of driving direction changing part  22  or the position and the weight of weight  210  is preferably determined such that moment F and moment W are in balance.  
         [0108]     In photographing apparatus  1  according to the embodiment of the present invention, weight increment W 1  (that is, increment from the weight previously balanced by the elastic force of coil spring  21 ) due to heat radiation part  120  is 2.5 g and weight W 2  of weight  210  is 1.67 g. Distance L 1  from the center of bearing part  18  to pin  29  is 11.0 mm and distance L 2  from the center of bearing part  18  to the gravity center of weight  210  is 16.5 mm. It is preferable that W 1 ×L 1 =W 2 ×L 2  is satisfied such that moment F and moment W are in balance. When the elastic force of coil spring  21  is very small and ignorable, the weight increment W 1  may be the total weight of the members driven by linear actuator  20 .  
         [0109]     Although, in the above-described example, the description is given on photographing apparatus  1  which is disposed such that lens part  101  is disposed at the lower side, photographing apparatus  1  may be advantageously disposed such that lens part  101  is disposed at the upper side in photographing apparatus  1  according to the embodiment of the present invention. This is because, in photographing apparatus  1 , moment F and moment W are in balance even when the directions thereof are in the opposite directions.  FIGS. 11A and 11B  are views showing another example of balance member  220  mounted on pickup device driving apparatus  70  of photographing apparatus  1  according to the embodiment of the present invention.  FIG. 11A  is a plan view showing a peripheral configuration of balance member  220 .  FIG. 11B  shows the state of pickup device driving apparatus  70 .  
         [0110]     In photographing apparatus  1  according to the embodiment of the present invention, since weight  210  for adjusting the balance is provided, it is possible to realize photographing apparatus  1  having the configuration that an overload is hard to be applied to linear actuator  20  although the lens part  101  is disposed at the upper or lower side.  
         [0111]     Although, in pickup device driving apparatus  70  according to the embodiment of the present invention, leaf springs  10  are formed between movable part  7  and first support part  8 , between movable part  7  and second support part  9 , between base surface  62  and first support part  8 , and between base surface  62  and second support part  9  as rotating part, pickup device driving apparatus according to the present invention is not limited to this configuration.  
         [0112]     For example, movable part  7 , first support part  8 , second support part  9 , and base part  6  may be separately provided and a hinge part may be formed between movable part  7  and first support part  8 , between movable part  7  and second support part  9 , between base surface  62  and first support part  8 , and between base surface  62  and second support part  9  as rotating part. According to this configuration, it is possible to realize a configuration with excellent impact resistance, in addition to the above-described effect. In such a configuration, an elastic means such as a coil spring for elastically connecting first support part  8  to second support part  9  is preferably provided in order to suppress rattle in the hinge part.  
         [0113]     Although, in photographing apparatus  1  according to the embodiment of the present invention, the central position of pickup surface  83  of pickup device  15  is changed in a direction (Y axis direction) perpendicular to the optical axis direction due to the movement of pickup device  15  in the optical axis direction (X axis direction). However, the displacement of pickup device  15  in the direction (Y axis direction) perpendicular to the optical axis direction can be removed in practice by providing a circuit for detecting the displacement thereof using a photo-interrupter or the like, calculating the displacement of pickup device  15  in the direction (Y axis direction) perpendicular to the optical axis direction, and shifting a read area of a signal by the displacement to perform correction in the circuit part. When the displacement of pickup device  15  in the optical axis direction (X axis direction) is small, a problem is not caused in practice although the above-described correction process is not performed.  
         [0114]     Although, in the embodiment of the present invention, the configuration for moving pickup device  15  mounted on pickup device driving apparatus  70  to be mounted on photographing device  1  in the optical axis direction in parallel by using the rectangular U-shaped member  80  and deforming it into a parallelogram is described, the pickup device driving apparatus and the photographing apparatus according to the present invention are not limited to this embodiment. Mechanisms for using driving part having axis, such as linear actuator  20 , changing the driving direction thereof using driving direction changing part  22  having bearing part  18  and transferring driving force to movable part  7  are all included in pickup device driving apparatus and photographing apparatus using the same according to the present invention.  
         [0115]     The pickup device driving apparatus according to the present invention is applicable to a structure in which a mechanism for moving pickup device holding part  11  in the optical axis direction of lens part  101  automatically moves pickup device holding part  11  using a driving means such as a motor or a structure for manually moving pickup device holding part  11  using a knob.  
         [0116]     Although, in the embodiment of the present invention, fan motor  130  is employed as a cooling part for cooling the other end of heat sink part  140 , the pickup device driving apparatus and the photographing apparatus according to the present invention is not limited to this configuration. For example, a known cooling device such as a Peltier device or a liquid cooling mechanism may be used as the cooling part.  
         [0117]     Although, in pickup device driving apparatus  70  according to the embodiment of the present invention, heat radiation part  120  which faces heat sink part  140  provided at the upper side in the case is provided in order to radiate heat generated in the vicinity of pickup device  15 , the pickup device driving apparatus and the photographing apparatus using the same according to the present invention are not limited to this configuration.  FIG. 12  shows another example of the pickup device driving apparatus and the photographing apparatus according to the embodiment of the present invention. For example, as shown in  FIG. 12 , pickup device driving apparatus  170  without heat radiation part  120  and photographing apparatus  180  using the same are included in pickup device driving apparatus and photographing apparatus using the same according to the present invention.  
         [0118]     Although, examples of mounting the pickup device driving apparatus according to the embodiments of the present invention on a monitoring camera apparatus are described, the use of the photographing apparatus according to the present invention is not limited to the monitoring camera apparatus. For example, the pickup device driving apparatus may be mounted on every known photographing apparatus such as a video camera or a digital camera.  
       INDUSTRIAL APPLICABILITY  
       [0119]     As described above, according to a pickup device driving apparatus and a photographing apparatus using the same according to the present invention, even when a pickup device is moved in an optical axis direction, it is possible to allow heat generated in the vicinity of the pickup device to escape without generating a frictional force. The present invention is applicable to a photographing apparatus such as a monitoring camera apparatus or a video camera apparatus, and more particularly, to a pickup device driving apparatus for moving a pickup device in an optical axis direction of a lens part and a photographing apparatus using the same.

Technology Category: 5