Patent Publication Number: US-8966712-B1

Title: Door operator

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a mechanism for opening and closing a door, and more particularly to a door operator. 
     2. Description of Related Art 
     A conventional door operator is applied to close and open a door. The door operator can close the door automatically to prevent the air leaking from indoor area and to keep dirt or cats and dogs stay at the outdoor area. The door operator also can help a user to open doors in a labor-saving manner. 
     The conventional door operator is usually mounted between a door and a door frame and has a swinging arm and a cylinder. When the door is opening, the swinging arm is moved to push or pull a piston of the cylinder. Air inside of the cylinder will flow and generate a cushion effect by pushing or pulling the piston, and then the door can be closed or opened by the door operator automatically and easily. 
     However, a stroke of the cylinder of the conventional door operator is relative long so a length of a housing and the volume of the door operator are relative large. As such, the appearance of the door operator is not appealing enough. 
     To overcome the shortcomings of the conventional door operator, the present invention provides a door operator to mitigate or obviate the aforementioned problems. 
     SUMMARY OF THE INVENTION 
     The main objective of the invention is to provide a door operator; the door operator includes an installation box, an operating mechanism, a pneumatic apparatus, and a moveable sleeve. 
     The installation box has a housing and a lid; the housing has a top, a bottom, an assembling space, and an opening communicating with the assembling space; the lid is mounted in the opening and covers the assembling space. 
     The operating mechanism is rotatably connected with the installation box and has a shaft, a gear, a swing arm and a rack; the shaft is rotatably mounted on the top of the housing through the bottom of the housing; the gear is mounted on the shaft, is driven by the shaft, and has a rotation axis; the swing arm has two ends, one of the ends of the swing arm is pivotally mounted on a top end of the shaft and outside the housing; the rack is connected to the other end of the swing arm. 
     The pneumatic apparatus is installed in the assembling space and has a cylinder, a piston rod, an adjusting rod, a piston block, a sealing ring, a clutch ring, a first spring, and a second spring. 
     The cylinder has an inner space and an insertion hole communicating with the inner space. 
     The piston rod is moveably mounted in the insertion hole of the cylinder. 
     The adjusting rod is connected with the piston rod and has an air-in slit longitudinally formed in a periphery of the adjusting rod. 
     The piston block is mounted around the adjusting rod and has a first face, an abutment recess, multiple air outlets and an air inlet; the first face is defined at one side of the piston block, the abutment recess is formed in the first face of the piston block and has a bottom, the air outlets are formed through the bottom of the abutment recess and arranged circularly, the air inlet is mounted through a periphery of the piston block and corresponding in position to and communicating with the air-in slit. 
     The sealing ring is mounted in the abutment recess and covers the air outlets. 
     The clutch ring is mounted around the adjusting rod and engaged with the piston block. 
     The first spring abuts between the clutch ring and the piston rod. 
     The second spring is mounted in the abutment recess and abuts between the sealing ring and the clutch ring. 
     The moveable sleeve is movably mounted around the cylinder and connected with the piston rod; the moveable sleeve has a gear face and a central axis, the central axis of the moveable sleeve is perpendicular to the rotation axis of the gear, and the gear face is correspondingly engaged with the gear. 
     Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawing. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view in partial section of a door operator in accordance with the present invention; 
         FIG. 2  is an exploded perspective view of an operating mechanism of the door operator in  FIG. 1 ; 
         FIG. 3  is a cross-sectional top view of the door operator along line  3 - 3  in  FIG. 1 ; 
         FIG. 4  is an enlarged cross-sectional top view of the door operator in  FIG. 3 ; 
         FIG. 5  is an exploded perspective view of a pneumatic apparatus of the door operator in  FIG. 3 ; 
         FIG. 6  is an enlarged side view in partial section of the door operator along line  6 - 6  in  FIG. 1 ; 
         FIG. 7  is an operational top view of the door operator in  FIG. 1  in a door closing status; 
         FIG. 8  is another operational top view of the door operator in  FIG. 1  in a door opening status; 
         FIG. 9  is a side view in partial section of the door operator along line  9 - 9  in  FIG. 7 ; 
         FIG. 10  is an operational side view in partial section of the door operator in  FIG. 9 ; 
         FIG. 11  is an operational side view in partial section of the pneumatic apparatus of the door operator in  FIG. 9 ; and 
         FIG. 12  is another operational side view in partial section of the pneumatic apparatus of the door operator in  FIG. 10 . 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENT 
     With reference to  FIGS. 1 to 5 , a preferred embodiment of a door operator in accordance with the present invention has an installation box  10 , an operating mechanism  20 , a pneumatic apparatus  30  and a moveable sleeve  40 . 
     With reference to  FIGS. 1 and 2 , the installation box  10  has a housing  11  and a lid  12 . The housing  11  has a top, a bottom, an assembling space  110 , an opening  111 , a through hole  112  and an assembling hole  113 . The assembling space  110  is formed inside the housing  11 . The opening  111  is formed in the housing  11  and communicates with the assembling space  110 . The through hole  112  is formed in the top of the housing  11 . The assembling hole  113  is formed in the bottom of the housing  11 . The through hole  112  and the assembling hole  113  are coaxial with each other and communicate with the assembling space  110 . The lid  12  is mounted in the opening  111  and closes the assembling space  110 . 
     With reference to  FIGS. 1 and 2 , the operating mechanism  20  is rotatably connected with the installation box  10  and has a shaft  21 , a gear  22 , a swing arm  23  and a rack  24 . The shaft  21  is rectangular in cross section, and is rotatably mounted through the through hole  112  and the assembling hole  113 . The gear  22  is mounted around the shaft  21  and is accommodated in the assembling space  110 . The gear  22  has a rotation axis and is driven by the shaft  21 . The swing arm  23  has two ends, and one of the ends of the swing arm  23  is pivotally mounted on a top end of the shaft  21  and outside the housing  11 . The rack  24  has two ends, one of the ends of the rack  24  is connected to the other end of the swing arm  23 , and the other end of the rack  24  can be installed on a door frame. 
     With reference to  FIGS. 3 ,  4  and  5 , the pneumatic apparatus  30  is installed in the assembling space  110  and has a cylinder  31 , a piston rod  32 , an adjusting rod  33 , a piston block  34 , a sealing ring  35 , a clutch ring  36 , a first spring  37  and a second spring  38 . 
     The cylinder  31  is circular in cross section and is mounted in the assembling space  110 . The cylinder  31  has an axis, two ends, an inner space  311 , an insertion hole  312 , a screw hole  313  and an adjusting screw  314 . The inner space  311  is formed inside the cylinder  31 . The insertion hole  312  and the screw hole  313  are respectively formed at the two ends of the cylinder  31 . The insertion hole  312  communicates with the inner space  311 . The end of the cylinder  31  in which the screw hole  313  is formed is mounted on the housing  11 . The adjusting screw  314  is adjustably screwed into the screw hole  313 . 
     The piston rod  32  is moveably mounted in the insertion hole  312  of the cylinder  31 . The piston rod  32  has two ends and a connecting hole  321 . The connecting hole  321  is a threaded hole and is formed at one of the ends of the piston rod  32  that is inserted into the inner space  311  from the insertion hole  312 . 
     The adjusting rod  33  is connected with the piston rod  32 . The adjusting rod  33  sequentially includes a connecting portion  331 , a fixing portion  332 , a piston portion  333  and a protrusion  334 . The connecting portion  331  is threaded and is screwed into the connecting hole  321 . The fixing portion  332  is rectangular in cross section. A width of the fixing portion  332  is larger than a diameter of the connecting portion  331 . The piston portion  333  is cylindrical and has an air-in slit  3331 . The air-in slit  3331  is formed longitudinally in a periphery of the piston portion  333  and has a shallow end and a deep end. The air-in slit  3331  becomes gradually deep from the shallow end to the deep end. The distance from the deep end to the piston rod  32  is longer than the distance from the shallow end to the piston rod  32 . A diameter of the piston portion  333  is smaller than the width of the fixing portion  332 . The protrusion  334  is threaded. 
     The piston block  34  is cylindrical and is sleeved around the adjusting rod  33  and can be moved along the adjusting rod  33 . The piston block  34  is accommodated in the inner space  311  of the cylinder  31  and divides the inner space  311  into a first chamber  3111  and a second chamber  3112 . The first chamber  3111  is located adjacent to the insertion hole  312 , and the second chamber  3112  is located away from the insertion hole  312  relative to the first chamber  3111 . The piston block  34  has an axis, a first face  341 , a second face  342 , a fitting hole  343 , an abutment recess  344 , multiple air outlets  345  and an air inlet  346 . 
     The first face  341  and the second face  342  are respectively defined at the two sides of the piston block  34 . A waved face  3411  is formed on an outer edge of the first face  341 . The fitting hole  343  is formed in a center of the first face  341  and the piston portion  333  is fitted into the fitting hole  343 . A threaded face  3431  is formed inside the fitting hole  343  and adjacent to the second face  342 . The protrusion  334  is correspondingly screwed with the threaded face  3431 . The face  3431  may be integrated with the piston block  34  or may be formed on a nut that is mounted inside the fitting hole  343 . 
     The abutment recess  344  is formed in the first face  341  around the fitting hole  343  and has a bottom. The air outlets  345  are formed through the bottom of the abutment recess  344 , extend to the second face  342  and are arranged circularly. The air inlet  346  is formed through a periphery of the piston block  34  and corresponds in position to and communicates with the air-in slit  3331 . 
     The sealing ring  35  is mounted in the abutment recess  344  and covers the air outlets  345 . 
     The clutch ring  36  is sleeved around the fixing portion  332  and has an engagement face  361 , an abutting face  362 , a fixing hole  363 , multiple air holes  364  and a spring recess  365 . The engagement face  361  and the abutting face  362  are respectively at two sides of the clutch ring  36  and are opposite each other. An outer edge of the engagement face  361  is wave-shaped and is correspondingly engaged with the waved face  3411 . The fixing hole  363  is rectangular, is formed through a center of the clutch ring  36 , and the fixing portion  332  of the adjusting rod  33  is correspondingly fitted into the fixing hole  363 . The air holes  364  are formed through the abutting face  362  and the engagement face  361  and are arranged around the fixing hole  363 . The spring recess  365  is formed in the engagement face  361  and is disposed around the fixing hole  363 . 
     The first spring  37  is mounted in the spring recess  365  and abuts between the clutch ring  36  and the piston rod  32 . 
     The second spring  38  is mounted in the abutment recess  344  and abuts between the sealing ring  35  and the clutch ring  36 . 
     With reference to  FIGS. 3 and 6 , the moveable sleeve  40  is cylindrical, is movably mounted around the cylinder  31 , is connected with the piston rod  32  and can be moved along the cylinder  31 . A central axis of the moveable sleeve  40  is perpendicular to the rotation axis of the gear  22 . The moveable sleeve  40  has a gear face  41 . The gear face  41  is formed on an outer periphery of the moveable sleeve  40  and has multiple gear recesses  411 . The gear recesses  411  are arranged longitudinally at intervals and are correspondingly engaged with the gear  22 . 
     With reference to  FIGS. 7 and 8 , the installation box  10  and the operating mechanism  20  are respectively installed on a door  50  and a door frame  51 . When the door  50  is opening or closing, the swing arm  23  and the rack  24  are swung toward or away from the door frame  51  and then the shaft  21  and the gear  22  are rotated counterclockwise or clockwise. 
     With reference to  FIGS. 9 and 10 , the moveable sleeve  40  is driven by the rotation of the gear  22  and can move along the cylinder  31  and then pulls or pushes the piston rod  32  in the cylinder  31 . In addition, the gear  22  and the moveable sleeve  40  are arranged perpendicular to each other, thus the horizontal length of the housing  11  and the volume of the installation box  10  are reduced such that the installation box has a simplistic appearance. 
     When the door  50  is opening, the position of the moveable sleeve  40  is changed as shown from  FIG. 9  to  FIG. 10 . With reference to  FIG. 11 , the piston rod  32  is pulled into the cylinder  31 , air in the second chamber  3112  of the cylinder  31  is compressed and flows from the second chamber  3112  to the first chamber  3111  via the air outlets  345 . The sealing ring  35  is pushed away from the abutment recess  344  by the air and then the second spring  38  is compressed so that the air can easily and quickly go out from the air holes  364  or a gap between the clutch ring  36  and the cylinder  31 . 
     After the piston rod  32  is stopped pulling, the second spring  38  pushes the sealing ring  35  to cover the air outlets  345  for keeping the air staying behind the piston block  34 . 
     When the door  50  is closing, the position of the moveable sleeve  40  is changed as shown from  FIG. 10  to  FIG. 9 . With reference to  FIG. 12 , the piston rod  32  is pulled from the cylinder  31  and then the air flows into the inner space  311  behind the piston block  34  via the air holes  364 , the fitting hole  343 , the air-in slit  3331  and air inlet  346 . The speed of the air flow is slow because the air can only enter the first chamber  3111  from the second chamber  3112  via the air-in slit  3331  and the air inlet  346 . Therefore, the closing speed of the door  50  is slower than the opening speed. 
     When the adjusting screw  314  is rotated, the cylinder  31  and the piston block  34  can be moved along the adjusting rod  33 . The air inlet  346  is moved to selectively align with the air-in slit  3331  at various positions with different depths for changing flow rates of air and the speed of the door closing. 
     Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.