Abstract:
A pan/tilt camera apparatus effectively photographs an object by adjusting a camera to a desired direction according to motion of the object through controlling a pan movement unit for horizontal rotation and a tilt movement unit for vertical rotation of the camera at the same time. The pan/tilt camera apparatus includes the camera for photographing an object, a first housing for receiving a part of the camera, the first housing rotating right/left in integration with the camera. The pan/tilt camera includes a tilt movement unit received in the first housing for moving the camera upward/downward, and a pan movement unit connected to the first housing. The pan movement unit moves the first housing right/left in a separate way from the tilt movement unit. A second housing receives the pan driving unit. A control unit generates an interrupt signal for driving both of the tilt and pan movement units according to the interrupt signal, and adjusts directions of the tilt and pan movement units by controlling rotary speeds of the tilt and pan movement units at each interrupt signal in order to move the camera along the path of the moving object.

Description:
BACKGROUND OF THE INVENTION 
     1. Technical Field 
     The present invention relates to a pan/tilt camera for intelligently photographing an object, and more particularly to a pan/tilt camera for effectively photographing an object by adjusting the camera to a desired direction according to motion of the object through controlling a pan movement unit for horizontal movement and a tilt movement unit for vertical movement at the same time. 
     2. Description of the Prior Art 
     A camera is to photograph an image, of which applications becomes broad in fields of a manless monitoring system, a picture phone, etc. Therefore, there are more needs for a function of rotating the camera to a desired direction. 
     A pan/tilt camera currently used is configured to move its direction right/left or upward/downward with use of at least two motors for x-axis movement and y-axis movement. A controller used for adjusting a direction of such camera employs a scan and detect method in which a user should directly watch for an object photographed through the camera on a screen of a view finder and intentionally adjust the object to a center of the view finder screen. Such scan and detect method may control the motors respectively with use of a remote controller and rotate the camera right/left or upward/downward along the object. 
     However, such conventional pan/tilt camera should control each motor for x-axis movement or y-axis movement with use of each function key, which makes movement of the camera unnatural. In addition, the conventional technique has difficulty to quickly capture motion of the object in fact that it takes much time for adjusting a direction of the camera. 
     SUMMARY OF THE INVENTION 
     Therefore, the present invention is designed to overcome problems of the prior art. An object of the present invention is to provide a pan/tilt camera, which may adjust its direction right/left and upward/downward at the same time by way of simultaneously controlling right/left rotation and upward/downward rotation thereof. 
     In order to obtain the object, the present invention provides a pan/tilt camera comprising: a camera for photographing an object; a first housing for receiving a part of the camera, the first housing possibly rotating right/left in integration with the camera; a tilt movement means received in the first housing for moving the camera upward/downward; a pan movement means connected to the first housing, the pan movement means moving the first housing right/left in a separate way from the tilt movement means; a second housing for receiving the pan driving means; and a control means for generating an interrupt signal, driving both of the tilt and pan movement means according to the interrupt signal, adjusting directions of the tilt and pan movement means with controlling rotatory speed of the tilt and pan movement means at each interrupt signal in order to move the camera along the object. 
     The tilt movement means may include a tilt motor for generating rotative force by using driving force from outside, the control means controlling rotatory speed and direction of the tilt motor; a reduction gearbox engaged with the tilt motor for reducing rotatory speed of the tilt motor to a desired rate; and a tilt gear engaged with the reduction gearbox for receiving the speed-reduced rotative force of the tilt motor, the tilt gear being engaged with a tilt shaft combined with a bracket for fixing the camera in order to rotate the camera upward/downward. 
     The pan movement means may include a pan motor for generating rotative force by using driving force from outside, the control means controlling rotatory speed and direction of the pan motor; a reduction gearbox engaged with the pan motor for reducing rotatory speed of the pan motor to a desired rate; and a pan gear engaged with the reduction gearbox for receiving the speed-reduced rotative force of the pan motor, the pan gear being engaged with a pan shaft formed vertically in integration with the first housing in order to rotate the first housing right/left. 
     The tilt motor may be a step motor and the control means may control the rotatory speed of the tilt motor by regulating pulse transmitted to the tilt motor. 
     The pan motor may also be a step motor and the control means may control the rotatory speed of the pan motor by regulating pulse transmitted to the pan motor. 
     The tilt shaft may be fixedly combined to the bracket for fixing the camera and rotationally combined to a side of the first housing; and the tilt shaft may rotate the camera and the bracket upward/downward at the same time when the tilt gear is rotating. 
     The pan shaft may be fixedly combined to a lower portion of the first housing and rotationally combined with a bracket fixed to the second housing; and the pan shaft may rotate the first housing and the camera right/left at the same time when the pan gear is rotating. 
     In order to perform the object, the present invention provides a pan/tilt camera including a camera for photographing an object; a first housing for receiving a part of the camera, the first housing possibly rotating right/left in integration with the camera, the first housing having a front portion and a rear portion; a housing combining unit for combining the front portion and the rear portion of the first housing; a driving unit received in the first housing for supplying rotative force with use of power from outside; a tilt shaft rotationally combined to both sides of the first housing at a position near the housing combining unit, the tilt shaft rotating the camera upward/downward by the rotative force of the driving unit; a pan shaft fixedly combined to a lower portion of the first housing, the pan shaft extending vertically; a tilt movement unit received in the first housing for moving the camera upward/downward; a pan movement unit for rotating the pan shaft right/left in a separate way from the tilt movement unit; a second housing for receiving the pan driving unit; a bracket combined with the second housing for fixing the pan shaft rotatable; and a control means for generating an interrupt signal, driving both of the tilt and pan movement means according to the interrupt signal, adjusting directions of the tilt and pan movement means with controlling rotatory speed of the tilt and pan movement means at each interrupt signal in order to move the camera along the object. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other features, aspects, and advantages of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings, in which like components are referred to by like reference numerals. In the drawings: 
     FIG. 1 is a front view for showing a pan/tilt camera according to the present invention; 
     FIG. 2 is a side view of the pan/tilt camera of FIG. 1; 
     FIG. 3 is a rear view of the pan/tilt camera of FIG. 1; 
     FIG. 4 is a side view for showing inner configuration of the pan/tilt camera according to the present invention; 
     FIG. 5 is a plane view of showing the inner configuration of the pan/tilt camera of FIG. 4; and 
     FIG. 6 is a rear view of FIG.  4 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. 
     FIG. 1 is a front view showing whole outer appearance of a pan/tilt camera  10  of the present invention. Referring to the figure, the pan/tilt camera  10  of the present invention includes seemingly a camera  20 , a first housing  30  and a second housing  40 . The camera  20  is for photographing an image, not limited to a specific one and can be any type of camera which meets needs of the present invention. The camera  20  is received in the first housing  30  and may expose its part required for photographing. 
     The first housing  30  has a camera guide  31  which is perforated in a predetermined shape to protrude a part of the camera  20 . The camera  20  may move upward/downward in the camera guide  31  in a manner described below. For the purpose of the upward/downward movement of the camera  20 , the camera guide  31  has an opening formed to extend vertically. In addition, since a lens of the camera  20  is commonly circular, it is preferred that upper and lower ends of the camera guide  31  are rounded in order to escape collision with the camera  20 . 
     The first housing  30  may rotate right/left in a manner described below. In addition, it is preferred in appearance that the first housing  30  has a spherical shape, an oval shape, or the like which is not inappropriate to rotate. The second housing  40  is positioned under the first housing  30 . The second housing  40  may have a rectangular shape, and is preferably slightly bigger than the first housing  30 . The second housing  40  may have a base  42  at a its bottom position. The base  42  is preferably detachable with the second housing  40  in order to facilitate to check and repair parts in the second housing  40 . 
     FIG. 2 is a side view of the pan/tilt camera  10  of FIG.  1 . Referring to the figure, the first housing  30  has a front portion and a rear portion both of which are manufactured separately and combined each other in assembly. A housing combining unit  32  shown in the figure is used for screw combination when combining the front and rear portions of the first housing  30 . 
     In addition, it can be seen that the camera  20  rotates upward/downward approximately on center of a horizontal centerline of the first housing  30 . At this time, range of upward/downward rotation of the camera  20  may be regulated optionally, but preferably about ±30° or more as required. In the figure, the camera shown in dashed lines indicates maximum position within which the camera  20  may rotate upward/downward when the range of upward/downward rotation is regulated to be ±30°. 
     At this point, a tilt shaft  68  (see FIG. 5) which may act for a central axis of upward/downward rotation of the camera  20  is combined to the first housing  30 . For the purpose of combination of the tilt shaft  68 , a tilt shaft combining unit  34  is formed at side ends of the first housing  30 . The tilt shaft combining unit  34  may be protruded at side ends of the spherical or oval first housing  30 , and a coupling screw  36  may be positioned within the protruded tilt shaft combining unit  34  in order to screw the tilt shaft  68  thereto. At this time, the tilt shaft combining unit  34  may be protruded in a ring shape having a predetermined size in order to prevent the coupling screw  36  from jutting out and have an inward depressed center portion where the coupling screw  36  is located. In addition, the sides of the first housing  30  where the tilt shaft combining unit  34  is positioned may be preferably flattened such that the tilt shaft combining unit  34  may not protrude to excess. 
     FIG. 3 is a rear view of the pan/tilt camera  10  of FIG.  1 . Referring to the figure, position of the housing combining unit  32  described above is well shown. Preferably, the housing combining unit  32  is formed near the tilt shaft combining unit  34  in the embodiment of the present invention. If the first housing  30  consisting of two portions is combined near the tilt shaft combining unit  34  by the housing combining unit  32 , the tilt shaft combining unit  34  becomes structurally securer owing to firm combination of the first housing  30 . 
     In addition, the second housing  40  may include a plurality of connecting ports at its rear side for connection with external devices. In the embodiment of the present invention, the second housing  40  includes a communication port  44  connected to. a computer or another manipulating unit, a video output  46  for transmitting image information photographed by the camera, and a power input  48  for receiving power from outside, which is only an example and can be, of course, varied in real application according to circumstance and needs. In particular, the communication port  44  may employ a connecting unit for a data transmitting terminal or its passage such as a Universal Serial Bus UBS connecting port, a Universal Asynchronous Receiver Transmitter UART, or an RS- 232 C. 
     FIG. 4 to FIG. 6 are side, plane and front views showing internal configuration of the pan/tilt camera  10  respectively according to the present invention. Referring to the figures, the pan/tilt camera  10  of the present invention generally includes the camera  20  for photographing an object, the first housing  30  for receiving a part of the camera  20 , a tilt movement unit  60  received in the first housing  30  for rotating the camera  20  upward/downward, a pan movement unit  80  connected to the first housing  30  for rotating the first housing  30  right/left in a separate way from the tilt movement unit  60 , the second housing  40  for receiving the pan movement unit  80 , and a control unit  100  for controlling movement direction and speed of the tilt movement unit  60  and the pan movement unit  80  at the same time. 
     As shown in the figures, the camera  20  is fixed to a bracket  24  through such as a screw. The bracket  24  is screwed to the tilt shaft  68  fixed to the first housing  30 . As described above, the tilt shaft  68  is combined to both side ends of the first housing  30  so to possibly rotate horizontally by the tilt movement unit  60 , which is described later. Rotation of the tilt shaft  68  makes the bracket  24  and the camera  20  rotated. 
     At an approximately opposite position to the camera  20 , the first housing  30  has another bracket  64  fixedly combined thereto. The tilt movement unit  60  is fixed to the bracket  64  in order to rotate the camera  20  upward/downward. 
     The tilt movement unit  60  includes a tilt motor  62  for generating rotative force by using driving force from outside, a reduction gearbox  70  engaged with the tilt motor  62  for reducing rotatory speed of the tilt motor  62  to a desired rate, and a tilt gear  66  engaged with the reduction gearbox  70  and the tilt shaft  68  combined with the bracket  24  for fixing the camera  20  in order to rotate the camera  20  upward/downward. 
     At this time, the tilt motor  62  may preferably be a step motor or a pulse motor. In addition, it is preferred that the control unit  100  regulates pulse to the motor  62  in order to control rotatory speed of the motor  62 . 
     Since the motor for providing rotatory force with use of outside power usually rotates at very high speed, the reduction gearbox  70  is required to reduce the rotatory speed. The reduction gearbox  70  has a plurality of gears with which the rotatory speed of the motor may be reduced to a desired rate. The gears may be various reduction gear ratios such as 1:40, 1:48, 1:50, which is adjustable as requested. 
     A last gear of the reduction gearbox  70 , which rotates at reduced speed, is coaxially integrated with the tilt gear  66 , which may rotate the camera  20 . The tilt gear  66  is also engaged with the tilt shaft  68  combined with the first housing  30  so to rotate the tilt shaft  68 . At this time, the tilt shaft  68  includes a gear unit  69  to engage with the tilt gear  66 , which gear unit  69  may be formed at a predetermined position of the tilt shaft  68  or have a separate gear fixed to a predetermined position of the tilt shaft  68 . In addition, change of tooth number of the gear unit  60 , of course, makes rotatory speed of the tilt gear  66  being regulated one more time. 
     If the tilt shaft  68  rotates by the tilt gear  66 , the camera fixing bracket  24  fixedly combined with the tilt shaft  68  and the camera  20  fixed to the bracket  24  simultaneously rotate upward/downward. 
     Referring to FIG. 4 again, a pan shaft  88  is vertically attached to a lower end of the first housing  30  which receives a part of the camera  20  and the tilt movement unit  60 . The pan shaft  88  acts for a vertical rotary axis of the first housing  30 . A lower end of the pan shaft  88  is extended through the second housing  40 . The pan shaft  88  is engaged with the pan movement unit  80  within the second housing  40 . 
     The pan movement unit  80  includes a pan motor  82  for generating rotative force by using driving force from outside, a reduction gearbox  90  engaged with the pan motor  82  for reducing rotatory speed of the pan motor  82  to a desired rate, and a pan gear  86  engaged with the reduction gearbox  90  and the pan shaft  88  formed vertically in integration with the first housing  30  in order to rotate the first housing  30  right/left. 
     Configuration of the pan motor  82  and the reduction gearbox  90  for the pan motor  82  is same as or similar to that of the tilt motor  62  and the reduction gearbox  70  for the tilt motor  62 , and not described in detail here. 
     The reduction gearbox  90  reducing the rotatory speed of the pan motor  82  is engaged with the pan gear  86 . The pan gear  86  is also engaged with a gear unit  89  of the pan shaft  88  in order to rotate the pan shaft  88 , which is similar to the tilt shaft  68 . Since the pan shaft  88  is combined with the first housing  30 , rotation of the pan shaft  88  makes the first housing  30  being rotated right/left. At this time, rotating range of the first housing  30  may be regulated to a desired degree, and the embodiment of the present invention regulates the first housing  30  to possibly rotate ±90° right/left. However, the present invention is not limited to that, may select various modification as required. For example, the first housing  30  may rotate round and round, of course. 
     The pan shaft  88  is also connected to a shaft bearing  91 . Because the shaft bearing  91  is fixed to the second housing  40  by a bracket  84 , the pan shaft  88  may rotate freely at its fixed position. 
     The second housing  40  also receives the control unit  100 . The control unit  100  is to control rotatory direction and speed of the tilt movement unit  60  and the pan movement unit  80 . Though not shown in the figures, the control unit  100  may include a timer, a main processor, and a plurality of memories. The timer periodically generates interrupt signals for driving the tilt motor  62  or the pan motor  82 . The main processor controls the tilt motor  62  and the pan motor  82  in turn respectively with modulating rotatory speed according to each of the interrupt signals from the timer. Therefore, the main processor controls the horizontal movement by the pan motor  82  and the vertical movement by the tilt motor  62  of the camera  20  to a desired direction and a desired angle such that the camera  20  may adjust its direction along movement of the object. The memories store data and programs for operating the main processor. The memories may include, for example, a ROM for storing the program to operate the tilt and pan motor  62 ,  82 , a RAM for storing data and a NVRAM (Non Volatile RAM) for possibly storing data used to automatic camera control in case of even a power failure. 
     This embodiment employs a printed circuit board  98  (PCB) positioned at a bottom of the second housing  40  supporting the control unit  100 , which is just an example and may be an onboard type as a separate module or installed to a side of the second housing  40 , selectively. 
     Though not shown well in the drawings, each motor  62 ,  82  connects with a cable in order to receive power from outside and control signal from the control unit  100 . At this time, the pan motor  82  is structurally positioned near the control unit  100  and the power input  48 , while the tilt motor  62  is structurally separated therefrom because the tilt motor  62  is in the first housing  30 . Therefore, the pan shaft  88  has a cylindrical shape positioned at a connecting portion between first housing  30  and the second housing  40 . Through the cylindrical pan shaft  88 , a cable is connected to receive image signal from the camera  20  and transmit power and control signals to the tilt motor  62 . 
     While the tilt movement unit  60  and the pan movement unit  80  are installed separately so to make vertical rotation of the tilt movement unit  60  and horizontal rotation of the pan movement unit  80  separately, the present invention has characteristics in that the control unit  100  may control the vertical and horizontal movement at the same time. 
     For such reason, the control unit  100  compares a screen center of the camera  20  with a center position of an object detected by the camera  20 , calculates rotatory direction and angle of the camera  20  to move, and then drives the tilt motor  62  and the pan motor  82  according to the timer pulses in a certain period. When driving the tilt motor  62  and the pan motor  82 , the control unit  100  regulates rotatory direction and speed of the motors at each period of the timer pulses and subsequently proceeds such regulation, resulting that the camera  20  may quickly rotate to a desired direction. 
     The control unit  100  may be configured to operate separately, and possibly connected to an outside computer through the UBS port  44  so to be controlled by a command from such computer. 
     The present invention as constructed above has an advantage that the camera may quickly adjust its direction toward a desired object by performing right/left rotation and upward/downward rotation at the same time by separate driving units. 
     In addition, the present invention has another advantage of enhancing time efficiency by controlling right/left and upward/downward rotation of the camera at the same time and facilitating rotatory speed of the camera. 
     The pan/tilt camera according to the present invention has been described in detail. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.