Abstract:
An X-ray detecting device comprises a support mechanism for supporting a detector housing pivotably about a horizontal shaft parallel to an X-ray incidence surface, a shaft connected at one end to the detector housing and having an opposite end adapted to perform a rectilinear motion to induce a pivotal motion of the detector housing, a drive mechanism having a drive end connected to the opposite end of the shaft, the drive mechanism inducing the rectilinear motion of the opposite end of the shaft in a mutually connected state of the drive end and the opposite end of the shaft, a switching mechanism for between connection and non-connection of the opposite end of the drive shaft and the drive end, a brake mechanism for inhibiting the pivotal motion of the detector housing, and brake operating means for switching between operation and non-operation of the brake mechanism.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of Chinese Patent Application No. 200810099125.9 filed May 9, 2008, which is hereby incorporated by reference in its entirety. 
       BACKGROUND OF THE INVENTION 
       [0002]    The embodiments described herein relate to an X-ray detecting device and an X-ray imaging apparatus. Particularly, the embodiments described herein are concerned with an X-ray detecting device including a detector housing having an X-ray incidence surface whose direction is changeable, as well as an X-ray imaging apparatus equipped with such an X-ray detecting device. 
         [0003]    In an X-ray imaging apparatus, X-ray is radiated from an X-ray irradiator to a subject and transmitted X-ray is detected by an X-ray detector to form a radioscopic image. A certain X-ray imaging apparatus uses an X-ray stand. In the X-ray stand, a detector housing which incorporates an X-ray detector is supported by a vertical column. The X-ray stand is constructed such that the height of the detector housing and the direction of an X-ray incidence surface can be adjusted in accordance with a region to be radiographed (see, for example, Japanese Unexamined Patent Publication No.  2004 - 298473 ). 
       BRIEF DESCRIPTION OF THE INVENTION 
       [0004]    Adjustment of the direction of an X-ray incidence surface in a detector housing is performed using the power of a motor for example, but it is required that the direction be also adjustable manually for taking an appropriate measure in the event of motor failure or emergency. 
         [0005]    Accordingly, embodiments of the present invention provide an X-ray detecting device in which the direction of an X-ray incidence surface of a detector housing can be adjusted by both power and hand, as well as an X-ray imaging apparatus equipped with such an X-ray detecting device. 
         [0006]    A first aspect of the present invention provides an X-ray detecting device, with the direction of an X-ray incidence surface of a detector housing of the X-ray detecting device being changeable, comprising: a support mechanism for supporting the detector housing pivotably about a horizontal shaft parallel to the incidence surface; a shaft connected at one end thereof to the detector housing and having an opposite end adapted to perform a rectilinear motion to induce a pivotal motion of the detector housing; a drive mechanism having a drive end connected directly or indirectly to the opposite end of the shaft, the drive mechanism inducing the rectilinear motion of the opposite end of the shaft in a mutually connected state of the drive end and the opposite end of the shaft; a switching mechanism for switching from one to the other between connection and non-connection of the opposite end of the shaft and the drive end; a brake mechanism for inhibiting the pivotal motion of the detector housing; and a brake operating means for switching from one to the other between operation and non-operation of the brake mechanism. 
         [0007]    A second aspect of the present invention, in combination with the above first aspect, provides an X-ray detecting device further comprising a shaft support joined to the opposite end of the shaft and a restriction mechanism for restricting a moving direction of the shaft support, wherein the drive end is connected to the shaft support. 
         [0008]    A third aspect of the present invention, in combination with the above first aspect, provides an X-ray detecting device wherein the support mechanism supports a back surface of the detector housing by being apart from the horizontal shaft disposed on the back side of the detector housing. 
         [0009]    A fourth aspect of the present invention, in combination with the above third aspect, provides an X-ray detecting device wherein the support mechanism has a pair of parallel support arms spaced from each other in the direction of the horizontal shaft. 
         [0010]    A fifth aspect of the present invention, in combination with the above fourth aspect, provides an X-ray detecting device wherein the support arms are engaged with the horizontal shaft at respective ends on the side opposite to the detector housing. 
         [0011]    A sixth aspect of the present invention, in combination with the above second aspect, provides an X-ray detecting device, wherein the restriction mechanism comprises: a rectilinear rail; and a slider adapted to move on the rail while carrying the shaft support thereon. 
         [0012]    A seventh aspect of the present invention, in combination with the above second aspect, provides an X-ray detecting device, wherein the drive mechanism comprises: a motor; a drive shaft connected at a drive end thereof to the shaft support and adapted to be driven by the motor to thereby reciprocate in a rectilinear direction; and a second support mechanism for supporting the motor and the drive shaft pivotably about a second horizontal shaft parallel to the horizontal shaft on the side opposite to the drive end, causing a force induced by a turning moment to act on the contact portion between the drive end and the shaft support. 
         [0013]    An eighth aspect of the present invention, in combination with the above seventh aspect, provides an X-ray detecting device wherein the switching mechanism has a lever for lifting the drive mechanism to pull the drive end apart from the shaft support. 
         [0014]    A ninth aspect of the present invention, in combination with the above first aspect, provides an X-ray detecting device wherein the brake mechanism comprises: a second shaft connected at one end thereof through a pin parallel to the horizontal shaft to a position spaced apart from the horizontal shaft on a back side of the detector housing; and a brake for inhibiting movement of the second shaft. 
         [0015]    A tenth aspect of the present invention, in combination with the above ninth aspect, provides an X-ray detecting device wherein the brake is an electromagnetic brake. 
         [0016]    An eleventh aspect of the present invention provides an X-ray imaging apparatus comprising an X-ray detecting device, with the direction of an X-ray incidence surface of a detector housing of the X-ray detecting device being changeable, and an X-ray irradiation device, the X-ray detecting device comprising: a support mechanism for supporting the detector housing pivotably about a horizontal shaft parallel to the X-ray incidence surface; a shaft connected at one end thereof to the detector housing and having an opposite end adapted to perform a rectilinear motion to induce a pivotal motion of the detector housing; a drive mechanism having a drive end connected directly or indirectly to the opposite end of the shaft, the drive mechanism inducing the rectilinear motion of the opposite end of the shaft in a mutually connected state of the drive end and the opposite end of the shaft; a switching mechanism for switching from one to the other between connection and non-connection of the opposite end of the shaft and the drive end; a brake mechanism for inhibiting the pivotal motion of the detector housing; and brake operating means for switching from one to the other between operation and non-operation of the brake mechanism. 
         [0017]    A twelfth aspect of the present invention, in combination with the above eleventh aspect, provides an X-ray imaging apparatus further comprising: a shaft support joined to the opposite end of the shaft; and a restriction mechanism for restricting a moving direction of the shaft support, wherein the drive end is connected to the shaft support. 
         [0018]    A thirteenth aspect of the present invention, in combination with the above eleventh aspect, provides an X-ray imaging apparatus wherein the support mechanism supports a back surface of the detector housing by being apart from the horizontal shaft disposed on the back surface side of the detector housing. 
         [0019]    A fourteenth aspect of the present invention, in combination with the above thirteenth aspect, provides an X-ray imaging apparatus wherein the support mechanism has a pair of parallel support arms spaced from each other in the direction of the horizontal shaft. 
         [0020]    A fifteenth aspect of the present invention, in combination with the above fourteenth aspect, provides an X-ray imaging apparatus wherein the support arms are engaged with the horizontal shaft at respective ends on the side opposite to the detector housing. 
         [0021]    A sixteenth aspect of the present invention, in combination with the above twelfth aspect, provides an X-ray imaging apparatus, wherein the restriction mechanism comprises: a rectilinear rail; and a slider adapted to move on the rail while carrying the shaft support thereon. 
         [0022]    A seventeenth aspect of the present invention, in combination with the above twelfth aspect, provides an X-ray imaging apparatus, wherein the drive mechanism comprises: a motor; a drive shaft connected at a drive end thereof to the shaft support and adapted to be driven by the motor to thereby reciprocate in a rectilinear direction; and a second support mechanism for supporting the motor and the drive shaft pivotably about a second horizontal shaft parallel to the horizontal shaft on the side opposite to the drive end, causing a force induced by a turning moment to act on the contact portion between the drive end and the shaft support. 
         [0023]    An eighteenth aspect of the present invention, in combination with the above seventeenth aspect, provides an X-ray imaging apparatus wherein the switching mechanism has a lever for lifting the drive mechanism to pull the drive end apart from the shaft support. 
         [0024]    A nineteenth aspect of the present invention, in combination with the above eleventh aspect, provides an X-ray imaging apparatus wherein the brake mechanism comprises: a second shaft connected at one end thereof through a pin parallel to the horizontal shaft to a position spaced apart from the horizontal shaft on a back side of the detector housing; and a brake for inhibiting movement of the second shaft. 
         [0025]    A twentieth aspect of the present invention, in combination with the nineteenth aspect, provides an X-ray imaging apparatus wherein the brake is an electromagnetic brake. 
         [0026]    In the embodiments described herein, the direction of a detector housing is changeable, and the X-ray detecting device comprises a support mechanism for supporting the detector housing pivotably about a horizontal shaft parallel to the X-ray incidence surface, a shaft connected at one end thereof to the detector housing and having an opposite end adapted to perform a rectilinear motion to induce a pivotal motion of the detector housing, a drive mechanism having a drive end connected directly or indirectly to the opposite end of the shaft, the drive mechanism inducing the rectilinear motion of the opposite end of the shaft in a mutually connected state of the drive end and the opposite end of the shaft, a switching mechanism for switching from one to the other between connection and non-connection of the opposite end of the shaft and the drive end, a brake mechanism for inhibiting the pivotal motion of the detector housing, and brake operating means for switching from one to the other between operation and non-operation of the brake mechanism. Consequently, it is possible to provide an X-ray detecting device including a detector housing having an X-ray incidence surface whose direction is changeable, as well as an X-ray imaging apparatus having such an X-ray detecting device. 
         [0027]    The X-ray detecting device further comprises a shaft support joined to the opposite end of the shaft and a restriction mechanism for restricting a moving direction of the shaft support, and the drive end is connected to the shaft support. 
         [0028]    Consequently, the direction of the X-ray incidence surface of the detector housing can be adjusted properly. 
         [0029]    Since the support mechanism supports a back surface of the detector housing apart from the horizontal shaft disposed on the back surface side of the detector housing, the detector housing can be allowed to swing about the horizontal shaft. 
         [0030]    Since the support mechanism has a pair of parallel support arms spaced from each other in the direction of the horizontal shaft, it is possible to support the detector housing stably. 
         [0031]    Since the support arms are engaged with the horizontal shaft at respective ends on the side opposite to the detector housing, it is possible to utilize the length of each support arm. 
         [0032]    Since the restriction mechanism comprises a rectilinear rail and a slider adapted to move on the rail while carrying the shaft support thereon, it is possible to restrict the moving direction properly. 
         [0033]    The drive mechanism comprises a motor, a drive shaft connected at a drive end thereof to the shaft support and adapted to be driven by the motor and thereby reciprocate in a rectilinear direction, and a second support mechanism for supporting the motor and the drive shaft pivotably about a second horizontal shaft parallel to the horizontal shaft on the side opposite to the drive end, causing a force induced by a turning moment to act on the contact portion between the drive end and the shaft support. Consequently, the drive end can be brought into contact with the shaft support by utilizing the turning moment. 
         [0034]    Since the switching mechanism has a lever for lifting the drive mechanism to pull the drive end apart from the shaft support, it is possible to perform switching between contact and non-contact easily. 
         [0035]    The brake mechanism comprises a second shaft connected at one end thereof through a pin parallel to the horizontal shaft to a position spaced apart from the horizontal shaft on a back side of the detector housing and a brake for inhibiting movement of the second shaft. Consequently, it is possible to inhibit movement of the detector housing properly. 
         [0036]    Since the brake is an electromagnetic brake, it is possible to control the brake electrically. In this case, by providing the brake operating means with a switch for the electromagnetic brake, it is possible to operate the brake easily. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0037]      FIG. 1  is a view showing the construction of an exemplary X-ray imaging apparatus. 
           [0038]      FIG. 2  is a view showing an appearance of an arm which incorporates an angle adjusting mechanism. 
           [0039]      FIG. 3  is a view showing a constructional example of the angle adjusting mechanism. 
           [0040]      FIG. 4  is a view showing a constructional example of the angle adjusting mechanism. 
           [0041]      FIG. 5  is a view showing a constructional example of the angle adjusting mechanism. 
           [0042]      FIG. 6  is a view showing a constructional example of the angle adjusting mechanism. 
           [0043]      FIG. 7  is a view showing the structure of a lift mechanism. 
           [0044]      FIG. 8  is a view showing manual adjustment of the angle of a detector housing. 
           [0045]      FIG. 9  is a view showing manual adjustment of the angle of the detector housing. 
           [0046]      FIG. 10  is a view showing manual adjustment of the angle of the detector housing. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0047]    Embodiments of the invention will be described in detail with reference to the drawings. The present invention is not limited to the embodiments described herein. The construction of an exemplary X-ray imaging apparatus is shown schematically in  FIG. 1 . 
         [0048]    As shown in  FIG. 1 , this apparatus includes an X-ray irradiation device  200  and an X-ray detecting device  400 . The X-ray irradiation device  200  is made up of a column  210  suspended from a ceiling and an X-ray irradiator  220  attached to a lower end of the column  210 . The X-ray irradiator  220  can change its direction, thereby making it possible to change the X-ray irradiating direction. The column  210  which supports the X-ray irradiator  220  is capable of expansion and contraction in its longitudinal direction and is movable horizontally along the ceiling. The X-ray irradiation device  200  is an example of the X-ray irradiation device defined in the present invention. 
         [0049]    In the X-ray detecting device  400 , a carriage  420  is attached vertically movably to a column  410  which is erected upright on a floor, an arm  430  is attached to the carriage  420  horizontally, and a detector housing  440  is attached to a tip end portion of the arm  430 . The X-ray detecting device  400  is a so-called wall stand type X-ray detecting device. 
         [0050]    The X-ray detecting device  400  is an example of the best mode for carrying out the invention. With the construction of the X-ray detecting device  400 , there is shown an example of the best mode for carrying out the invention with respect to the X-ray detecting device. 
         [0051]    The detector housing  440  is a flat structure in the shape of a rectangular parallelepiped and incorporates an X-ray detecting panel. The detector housing  440  has an X-ray incidence surface whose inclination is adjustable so as to provide a horizontal or vertical state or any other desired angle in accordance with an incidence direction of X-ray. The detector housing  440  is an example of the detector housing defined in the present invention. 
         [0052]    An X-ray detection signal is inputted to an operator console  600  from the detector housing  440 . On the basis of the input signal from the detector housing  440 , the operator console  600  reconstruct a radioscopic image of the subject and displays it on a display  610 . 
         [0053]    The operator console  600  controls both X-ray irradiation device  200  and X-ray detecting device  400 . For the X-ray irradiation device  200 , the operator console  600  controls horizontal and vertical positions and X-ray irradiating direction of the X-ray irradiator  220  and further controls X-ray intensity and irradiation timing. For the X-ray detecting device  400 , the operator console  600  controls the height of the detector housing  440  so as to match the X-ray irradiator  220 , and adjusts the angle of the detector housing  440 , thereby controlling the direction of the X-ray incidence surface in conformity with the X-ray incidence direction. 
         [0054]    A mechanism for controlling the direction of the X-ray incidence surface of the detector housing  440  in accordance with a control signal provided from the operator console  600  is provided in the interior of the arm  430 . The following description is now provided about an angle adjusting mechanism for controlling the direction of the X-ray incidence surface. 
         [0055]      FIG. 2  shows an appearance of the arm  430  which incorporates the angle adjusting mechanism. As shown in  FIG. 2 , the arm  430  has a horizontal shaft  432  in an upper position of its tip and the detector housing  440  is attached to the horizontal shaft  432  pivotably through a bracket  442 . 
         [0056]    The bracket  442  is provided on a back side, namely, the side opposite to the X-ray incidence surface located on the surface side, of the detector housing  440 . With the bracket  442 , a predetermined distance from the horizontal shaft  432  up to the back surface of the detector housing  440  is ensured. 
         [0057]    With this distance as a radius the detector housing  440  pivots and causes the angle of the X-ray incidence surface to change from 90° (horizontal) to −20° via 0° (vertical). The angle of the X-ray incidence surface will also be referred to hereinafter as the angle of the detector housing. 
         [0058]    The angle adjustment of the detector housing  440  is performed by an angle adjusting mechanism  500  disposed within the arm  430 . The angle adjusting mechanism  500  is constructed so as to also permit manual adjustment of the angle of the detector housing  440 . 
         [0059]      FIGS. 3 ,  4  and  5  show a constructional example of the angle adjusting mechanism  500 .  FIGS. 3 ,  4  and  5  are vies of the angle adjusting mechanism  500  as seen sideways, from the front side, and from an obliquely downward position, respectively.  FIG. 6  is an enlarged view of a part of the angle adjusting mechanism  500 . The angle of the detector housing  440  is set at 90° (horizontal). 
         [0060]    As shown in  FIGS. 4 and 5 , the bracket  442  is an inverted U-shaped member. The horizontal portion of the bracket  442  is fixed to the back surface of the detector housing  440  and tip ends of the vertical portions on both sides are connected to upper positions of the tip end of the arm  430  through horizontal shafts  432   a  and  432   b , respectively. The horizontal shaft  432  and the bracket  442  are an example of the support mechanism defined in the present invention. 
         [0061]    The angle adjusting mechanism  500  has a shaft  510 . One end of the shaft  510  is connected through a pin  512  to a tip end of a support rod  444  suspending from the back surface of the detector housing. The support rod  444  is positioned ahead of the horizontal shafts  432   a  and  432   b . The pin  512  is parallel to the horizontal shaft  432 . The shaft  510  is an example of the shaft defined in the present invention. 
         [0062]    An opposite end of the shaft  510  is connected to a shaft support  520  through a pin  514 . The shaft support  520  underlies the horizontal shafts  432   a  and  432   b . The pin  514  is parallel to the pin  512 . The shaft support  520  is an example of the shaft support defined in the present invention. 
         [0063]    The shaft support  520  is fixed onto a slider  532 . The slider  532  is engaged with and movable along a rail  534 . The rail  534  is fixed to the interior of the arm  430 . The slider  532  and the rail  534  constitute a linear guide. The portion comprised of the slider  532  and the rail  534  is an example of the restriction mechanism defined in the present invention. 
         [0064]    A tip end of a drive shaft  550  of a drive mechanism  540  is connected to the shaft support  520 . As shown in  FIG. 6 , the tip end of the drive shaft  550  is put in contact from above with the shaft support  520  through an adaptor  554  which is connected to the drive shaft through a pin  552 . The pin  552  is parallel to the pin  514 . The shaft support  520  includes a horizontal surface with which a lower surface of the adaptor  554  is put in contact and a vertical surface with which a front end of the adaptor  554  is put in contact. 
         [0065]    An opposite end side of the drive shaft  550  is positioned within a cylinder  560 . In the interior of the cylinder  560  the power of a motor  570  acts on the drive shaft  550 . The motor  570  is integral with the cylinder  560 . With the power of the motor  570 , the drive shaft  550  reciprocates rectilinearly in its longitudinal direction. 
         [0066]    A base portion of the cylinder  560  is connected to a stud  564  through a pin  562 . The pin  562  is parallel to the pin  552 . The stud  564  is fixed to the interior of the arm  430 . The drive mechanism  540  is supported at both ends thereof by both stud  564  and shaft support  520 . 
         [0067]    The drive mechanism  540  is pivotable about the pin  562 . Consequently, a force based on a turning moment induced by the own weight of the drive mechanism  540  acts downwards on the contact portion between the adaptor  554  at the tip end of the drive shaft  550  and the shaft support  520 . 
         [0068]    In the drive mechanism  540 , as a result of reciprocating motion of the drive shaft  550  caused by forward and reverse rotations of the motor  570 , a lower end of the shaft  510  pinned to the shaft support  520  is allowed to reciprocate along the rail  534  and the detector housing  440  pinned to an upper end of the shaft  510  is allowed to pivot about the horizontal shaft  432 , thereby adjusting the angle of the X-ray incidence surface. 
         [0069]    The drive mechanism  540  is an example of the drive mechanism defined in the present invention. The motor  570  is an example of the motor defined in the present invention. The drive shaft  550  is an example of the drive shaft defined in the present invention. The portion comprised of the pin  562  and the stud  564  is an example of the second support mechanism defined in the present invention. 
         [0070]    The angle adjusting mechanism  500  includes a brake shaft  580 . One end of the brake shaft  580  is pinned to a tip end of a support rod  446  suspended from the back surface of the detector housing  440 . The support rod  446  is positioned ahead of the horizontal shafts  432   a  and  432   b . The pin is parallel to the horizontal shaft  432 . 
         [0071]    An opposite end side of the brake shaft  580  extends through a brake  590  which underlies the horizontal shaft  432 . The brake  590  inhibits the passing of the brake shaft  580  where required. A lower end portion of the brake  590  is fixed to the interior of the arm  430  through a hinge. A shaft of the hinge is parallel to the horizontal shaft  432 . As the brake  590  there is used, for example, an electromagnetic brake. 
         [0072]    The brake  590  turns OFF and ON in interlock with operation and non-operation, respectively, of the motor  570 . That is, during rotation of the motor  570 , the brake  590  does not obstruct the passing of the brake shaft  580 , while when the motor  570  is stopped, the brake  590  inhibits the passing of the brake shaft  580 . 
         [0073]    Therefore, while the drive mechanism  540  adjusts the angle of the detector housing  440 , the brake  590  does not operate, and when the angle adjustment is over, the brake  590  turns ON and maintains the angle of the detector housing  440 . 
         [0074]    The portion comprised of the brake shaft  580  and the brake  590  is an example of the brake mechanism defined in the present invention. The brake shaft  580  is an example of the second shaft defined in the present invention. The brake  590  is an example of the brake defined in the present invention. 
         [0075]    A lift mechanism  700  is annexed to the drive mechanism  540 . The lift mechanism  700  is for lifting the drive mechanism  540  to pull a drive end of the drive mechanism apart from the object to be driven. The lifting operation is performed by applying force from below to induce an upward pivoting motion of the drive mechanism  540  about the pin  562 . 
         [0076]    The lifting of the drive mechanism  540  is done when adjusting the angle of the detector housing  440  manually. Since the drive end moves apart from the object to be driven as a result of the lifting operation, it becomes easy to effect the manual adjustment of the angle. 
         [0077]    When the lifting operation is stopped, the drive mechanism  540  pivots downward and the drive end and the object to be driven again assume their contacted state. Thus, by operating the lift mechanism  700  manually, it is possible to switch from one to the other between contact and non-contact states of the drive end and the object to be driven. The lift mechanism  700  is an example of the switching mechanism defined in the present invention. 
         [0078]    It is necessary that the manual adjustment of the angle of the detector housing  440  be performed with the brake  590  OFF. A brake operating switch  448  is disposed on the back surface of the detector housing  440 . The switch  448  is an example of the brake operating means defined in the present invention. 
         [0079]      FIG. 7  shows the structure of the lift mechanism  700 . As shown in  FIG. 7 , the lift mechanism  700  comprises a shaft bar  702 , as well as a vertical arm  704  and a lateral arm  706  both secured to the shaft bar  702 . The shaft bar  702  is disposed under the drive mechanism  540  and in parallel with the horizontal shaft  432  and is attached to the arm  430  through a bearing (not shown). The vertical arm  704  is provided on one end of the shaft bar  702  at a position outside the arm  430 , while the lateral arm  706  is provided so as to face forward at an intermediate position of the shaft bar  702  and just under the drive mechanism  540 . The combination of the horizontal shaft bar  702  with the vertical arm  704  and the lateral arm  706  both provided on the shaft bar is an example of the lever defined in the present invention. 
         [0080]    The vertical arm  704  is a handle for manual operation. By turning the vertical arm  704  to the left, the drive mechanism  504  can be lifted with the lateral arm  706 . As a result of the lifting operation the adaptor  554  disposed at the tip end of the drive shaft  550  is pulled apart from the shaft support  520 . 
         [0081]    In this state, if the brake  590  is turned OFF by the switch  448 , the maintenance of the angle of the detector housing  440  is released, so that it becomes possible to manually adjust the direction of the detector housing  440 , as shown in  FIGS. 8 ,  9  and  10 . Then, if the brake  590  is actuated by the switch  448  in a desired state of inclination, the angle of the detector housing  440  is maintained.