Abstract:
An impact sensor for installation in a moving machine to detect an impact includes first and second electrically conductive strip and an insulative layer sandwiched therebetween. The first electrically conductive strip has at least one electrically conductive member facing but insulatively separated by the insulative layer from at least one electrically conductive member of the second electrically conductive strip. The insulative layer has a plurality of through holes, through at least one of which the electrically conductive member of the first electrically conductive strip and the electrically conductive member of the second electrically conductive strip are electrically contactable with each other when the second electrically conductive strip deforms under impact.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates generally to moving machines and more particularly, to an impact sensor for use in a moving machine to detect impacts. 
         [0003]    2. Description of the Related Art 
         [0004]    A typical impact sensor for use in a moving machine is an infrared design. For example, a robotic vacuum cleaner utilizes two infrared emitters to emit infrared light, and then reads the intersection area of the two light beams emitted by the two infrared emitters and determines the distance of the robotic vacuum cleaner relative to a wall or obstacle subject to the intersection area reading result. 
         [0005]    However, if the detected obstacle has a smooth surface that reflects light, the impact sensor may be unable to read the intersection area of the two infrared light beams accurately or may fail to read the intersection area of the two infrared light beams. Therefore, a conventional robotic vacuum cleaner may be unable to detect the presence of an obstacle during its movement. Improvement in this regard is necessary. 
       SUMMARY OF THE INVENTION 
       [0006]    The present invention has been accomplished under the circumstances in view. It is the main objective of the present invention to provide an impact sensor for a moving machine, which can accurately detect the presence of any obstacle, having excellent detection sensitivity. 
         [0007]    To achieve this objective of the present invention, the impact sensor for installation in a moving machine to detect an impact comprises first and second electrically conductive strips and an insulative layer sandwiched therebetween. The first electrically conductive strip has a strip body, on one side of which at least one electrically conductive member is provided. The second electrically conductive strip has a strip body, on one side of which at least one electrically conductive member facing the at least one electrically conductive member of the first electrically conductive strip is provided. The insulative layer separates the first electrically conductive member from the second electrically conductive member. The insulative layer has a plurality of through holes, through at least one of which the electrically conductive member of the first electrically conductive strip and the electrically conductive member of the second electrically conductive strip are electrically contactable with each other when the second electrically conductive strip deforms under impact. 
         [0008]    Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. 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. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         [0009]    The present invention will become more fully understood from the detailed description given herein below and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein: 
           [0010]      FIG. 1  is a perspective view of an impact sensor in accordance with a first embodiment of the present invention; 
           [0011]      FIG. 2  is an exploded view of the impact sensor in accordance with the first embodiment of the present invention; 
           [0012]      FIG. 3  is an exploded front view of the impact sensor in accordance with the first embodiment of the present invention; 
           [0013]      FIG. 4  is a sectional elevation of taken along line  4 - 4  of  FIG. 1 ; 
           [0014]      FIG. 5  is similar to  FIG. 4 , but showing that the metal electrically conductive members of the second electrically conductive strip are respectively forced into contact with the metal electrically conductive members of the first electrically conductive strip upon an impact; 
           [0015]      FIG. 6  is an exploded front view of an impact sensor in accordance with a second embodiment of the present invention; 
           [0016]      FIG. 7  is a cross sectional view of the impact sensor in accordance with the second embodiment of the present invention; and 
           [0017]      FIG. 8  is similar to  FIG. 7 , but showing that the metal electrically conductive members of the second electrically conductive strip are respectively forced into contact with the metal electrically conductive member of the first electrically conductive strip upon an impact. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0018]    Referring to  FIGS. 1-4 , an impact sensor  10  for use in a moving machine in accordance with a first embodiment of the present invention is shown comprised of a first electrically conductive strip  20 , an insulative layer  30 , a second electrically conductive strip  30 , a back glue  50 , and multiple metal terminals  60 . 
         [0019]    The first electrically conductive strip  20  includes a flat, narrow, elongated strip body  21  and two line-shaped electrically conductive members  22  protruded from one side, namely, the top side of the strip body  21  in a parallel manner and extending along the length of the strip body  21 . The line-shaped electrically conductive members  22  may be prepared from, but not limited to, a metal film or silver adhesive. Preferably, the line-shaped electrically conductive members  22  are made of a metal film in this embodiment. Further, according to this embodiment, there are two line-shaped electrically conductive members  22  provided at the strip body  21 . However, the amount of the electrically conductive member is not limited to two. 
         [0020]    The insulative layer  30  can be a plastic insulative strip. Alternatively, the insulative layer  30  can be prepared from a light curing adhesive. According to this embodiment, the insulative layer  30  is a plastic insulative strip, having its bottom side attached to the line-shaped electrically conductive members  22  of the first electrically conductive strip  20 . Further, the insulative layer  30  has through holes  32  cut through the top and bottom sides and arranged in a line along its length. The diameter of the through holes  32  is greater than the distance between the two line-shaped electrically conductive members  22  of the first electrically conductive strip  20 . 
         [0021]    The second electrically conductive strip  40  includes a flat, narrow, elongated strip body  41  and two line-shaped electrically conductive members  42  protruded from one side, namely, the bottom side of the strip body  41  in a parallel manner and extending along the length of the strip body  41 . The line-shaped electrically conductive members  42  of the second electrically conductive strip  40  are attached to the top side of the insulative layer  30  corresponding to the line-shaped electrically conductive members  22  of the first electrically conductive strip  20 . Further, the line-shaped electrically conductive members  42  may be prepared from, but not limited to, a metal film or silver adhesive. Preferably, the line-shaped electrically conductive members  42  are made of a metal film in this embodiment. Further, according to this embodiment, there are two line-shaped electrically conductive members  42  provided at the strip body  41 . However, the amount of the electrically conductive member  42  used is not limited to two. 
         [0022]    The back glue  50  can be applied to the bottom side of the strip body  21  of the first electrically conductive strip  20  or the top side of the strip body  41  of the second electrically conductive strip  40 . According to this embodiment, the back glue  50  is applied to the bottom side of the strip body  21  of the first electrically conductive strip  20  for bonding the impact sensor  10  to the outer surface of the housing of a moving machine (not shown). 
         [0023]    The metal terminals  60  are respectively connected to the line-shaped electrically conductive members  22  of the first electrically conductive strip  20  and the line-shaped electrically conductive members  42  of the second electrically conductive strip  40  for electrically connecting the impact sensor  10  to the internal electric circuit of the moving machine in which the impact sensor  10  is installed. 
         [0024]    Referring to  FIG. 5 , when the second electrically conductive strip  40  is forded by an external pressure toward the first electrically conductive strip  20 , for example, when the housing of the moving machine touched a wall or obstacle to compress the second electrically conductive strip  40 , the line-shaped electrically conductive members  42  of the second electrically conductive strip  40  will be forced to project through at least one of the through holes  32  of the insulative layer  30  into contact with the line-shaped electrically conductive members  22  of the first electrically conductive strip  20 , thereby causing a short circuit and further triggering of the moving machine. 
         [0025]    Multiple impact sensors  10  of the aforesaid design may be installed in the housing of a moving machine at different locations. When one impact sensor  10  is induced, the moving machine determines the direction of the obstacle subject to the location of the induced impact sensor  10 . Therefore, the use of the present invention in a moving machine enables the moving machine to accurately detect any obstacle, eliminating the detection problem of a conventional infrared type impact sensor. 
         [0026]      FIGS. 6-8  illustrate an impact sensor  12  in accordance with a second embodiment of the present invention. Similar to the aforesaid first embodiment, the impact sensor  12  is comprised of a first electrically conductive strip  70 , an insulative layer  80 , a second electrically conductive strip  90 , a back glue  110 , and multiple metal terminals  110 . According to this embodiment, the first electrically conductive strip  70  comprises a flat, narrow, elongated strip body  71  and one single electrically conductive member  72  protruded from one side, namely, the top side of the strip body  71  and extending along the length of the strip body  71 . The electrically conductive member  72  of the first electrically conductive strip  70  may be prepared from a metal film or silver adhesive. According to this embodiment, the electrically conductive member  72  is made of silver adhesive. The insulative layer  80  can be a plastic insulative strip. Alternatively, the insulative layer  80  can be prepared from a light curing adhesive. According to this embodiment, the insulative layer  80  is prepared from a light curing adhesive. Further, the insulative layer  80  has through holes  82  cut through the top and bottom sides and arranged in a line along its length. The second electrically conductive strip  90  comprises a flat, narrow, elongated strip body  91  and two electrically conductive members  92  protruded from one side, namely, the bottom side of the strip body  91  and extending along the length of the strip body  91 . The electrically conductive members  92  of the second electrically conductive strip  90  are attached to the top side of the insulative layer  80  corresponding to the electrically conductive member  72  of the first electrically conductive strip  70 . Further, the electrically conductive members  92  may be prepared from a metal film or silver adhesive. According to this embodiment, the electrically conductive members  92  are made of silver adhesive. Further, the diameter of the through holes  82  of the insulative layer  80  is approximately equal to the transverse width of the electrically conductive member  72  of the first electrically conductive strip  70  and greater than the transverse distance between the two electrically conductive members  92  of the second electrically conductive strip  90 . This second embodiment achieves the same effect as the aforesaid first embodiment. 
         [0027]    The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.