Patent Publication Number: US-2023137499-A1

Title: Quickly installed headrest adjustment device

Description:
BACKGROUND OF THE INVENTION 
     1. Fields of the Invention 
     The present invention relates to a chair, and more particularly, to a headrest adjustment device that can be quickly installed. 
     2. Descriptions of Related Art 
     Office chairs are developed competitively with new designs introduced to different types of office chairs. For high quality and high value office chairs, the manufacturers focus on the adjustment features regarding different parts of the office chairs, such as the angle adjustment of the headrest so as to provide the users to feel relaxation and get relief to muscles after a long time of office work, by resting the head and neck to the headrest. 
     However, the connection between the headrest and the chair back of the existing office chairs mostly rely on use of bolts, such as Taiwanese Patent Publication No. 1358999 which discloses a “general-use headrest assembly”, and Taiwanese Utility Model Publication No. M399658 which discloses a “securing device for headrest of office chair”. The users have to user rotatable tools to assemble and install the headrest to the chair after opening the box of the office chair. This is not convenient for the users. 
     The present invention intends to provide a headrest that is able to be installed quickly without use of tools. 
     SUMMARY OF THE INVENTION 
     The primary object of the present invention is to provide a mount case on a chair back, and the mount case includes a recessed area. The users can connect the adjustment device of the rail to the mount case of the chair back after opening the pack box and to quickly and conveniently install the headrest unit to the chair back. 
     The present invention relates to a quickly installed headrest adjustment device and comprises a mount case that is connected to a chair back and includes a recessed area, an engaging hole, a latch and a first contact face which is located on the rear side of the chair back. The recessed area is defined in the first contact face and including an inner bottom, two side slots and an inner side which extends from the lower end of the inner bottom of the recessed area. The engaging hole is located between the two side slots and defined through the inner bottom of the recessed area. The latch is connected to the inner top side of the engaging hole and includes a bottom face which protrudes beyond the engaging hole and faces the inner side of the recessed area. A headrest unit includes a rail and a headrest that is connected to one end of the rail. The rail includes a groove, and a first gear rack is located on one side of the groove. An adjustment device is mounted to the rail and includes a second contact face, two ridges, a block, a first space, a stepped recess and a button. The second contact face faces the first contact face. The two ridges protrude beyond the second contact face and are connected to the first contact face. Each ridge has multiple tongues that faces the side slot corresponding thereto. The block is located between the two ridges. The multiple tongues of each of the ridges are inserted into the side slot corresponding thereto so that the ridges are located in the recessed area and contact the inner side of the recessed area. The latch is pushed by the block, and the bottom face of the latch contacts the block. The first space faces the rail. The stepped recess is defined in one side of the first space and includes a stop face and a pivot. The button is pivotably connected to the pivot and includes a resilient tab and multiple engaging teeth which are located on the lower section of the button and face the first gear rack. The resilient tab extends from the upper section of the button and resiliently contacts the stop face. The button is pivoted by the resilient tab to engage the engaging teeth of the button with the first gear rack. The button is pushed and pivoted in an opposite direction to disengage the engaging teeth of the button from the first gear rack of the rail so that the rail is movable up and down along the adjustment device. 
     As one embodiment of the present invention, the latch includes an inclined face that faces the first contact face and is formed with the bottom face. The inclined face is configured to provide a buffering feature when the block is moved to push and deform the latch to enter into the engaging hole. 
     As one embodiment of the present invention, the mount case includes multiple through holes which are defined through the inner bottom of the recessed area so as to be connected to the chair back. Each through hole includes a circular recess that is formed in the inner bottom of the recessed area so as to accommodate heads of screws such that the heads of the screws do not protrude beyond the inner bottom of the recessed area. 
     As one embodiment of the present invention, the adjustment device includes a notch which accommodates the latch when the latch is deformed to release the block  4 . 
     As one embodiment of the present invention, the button is an inverted L-shaped button and includes a path which is located at the upper section of the button. The pivot is pivotably engaged with the path. 
     As one embodiment of the present invention, the present invention further includes a cover that includes a second space, and the rail is located between the second space of the cover and the first space of the adjustment device. 
     As one embodiment of the present invention, the groove of the rail includes a second gear rack which is located corresponding to the first gear rack. Two guide plates are axially located between the first gear rack and the second gear rack. The first space includes an inner bottom. A lug extends from the inner bottom of the first space and is inserted into the groove of the rail and engaged between the two guide plates so as to guide the rail along the adjustment device. 
     As one embodiment of the present invention, a buffering unit is inserted in the groove of the rail and located between the first gear rack and the second gear rack. The buffering unit includes a damp member and a gear. The damp member is fixed to the inner bottom of the first space. The gear is pivotably connected between the damp member and the second gear rack. The gear is engaged with the second gear rack and contacts the damp member so that when the second gear rack of the rail moves up and down to rotate the gear, the gear contacts the damp member to buffer movement of the second gear rack of the rail. 
     As one embodiment of the present invention, the first space includes two hooks to which the damp member is mounted, and a rod to which the gear is pivotably mounted. The two hooks and the rod are formed to the inner bottom of the first space. 
     As one embodiment of the present invention, the headrest unit includes a guide member which is pivotably connected to the headrest. The rail includes a reception recess defined in the top thereof. A bolt is radially connected to the reception recess. The guide member includes a lateral recess, an insertion facing the reception recess, a protrusion and a spring. The protrusion protrudes from the insertion and the spring is mounted to the protrusion. The reception recess receives the guide member. The spring is biased between the insertion and the inner end of the reception recess to resiliently move the headrest along the reception recess. The bolt protrudes into the lateral recess to prevent the guide member from disengaging from the lateral recess. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is an exploded view of the present invention; 
         FIG.  2    is a perspective view of the present invention; 
         FIG.  3    is an exploded view of the mount case and the adjustment device of the present invention; 
         FIG.  4    is a side cross sectional view to show the connection of the mount case and the adjustment device of the present invention; 
         FIG.  5    shows that the inclined face guide the block to push and deform the latch; 
         FIG.  6    is a cross sectional view, taken along line VI-VI in  FIG.  2   ; 
         FIG.  7    is a cross sectional view to show that the latch in  FIG.  6    is pushed to release the block; 
         FIG.  8    is an exploded view of the headrest unit and the adjustment device of the present invention; 
         FIG.  9    is a cross sectional view to show that the engaging teeth of the button are engaged with the first gear rack of the rail; 
         FIG.  10    is a cross sectional view to show that the engaging teeth of the button are disengaged from the first gear rack of the rail; 
         FIG.  11    shows that the first gear rack of the rail is released so as to make an upward adjustment; 
         FIG.  12    shows that the first gear rack of the rail is released so as to make a downward adjustment, and 
         FIG.  13    is a cross sectional view to show the resilient and retractable structure in the headrest unit. 
     
    
    
     SYMBOL DESCRIPTION OF MAIN COMPONENTS 
     chair back  100 ; mount case  10 ; first contact face  11 ; recessed area  12 ; inner bottom  121 ; side slot  122 ; inner side  123 ; engaging hole  13 ; latch  14 ; bottom face  141 ; inclined face  142 ; through hole  15 ; circular recess  151 ; headrest unit  20 ; rail  21 ; groove  211 ; first gear rack  2111 ; second gear rack  2112 ; reception recess  212 ; bolt  213 ; headrest  22 ; guide member  23 ; lateral recess  231 ; insertion  232 ; protrusion  233 ; spring  234 ; adjustment device  30 ; second contact face  31 ; ridge  32 ; tongue  321 ; notch  33 ; block  34 ; first space  35 ; inner bottom  351 ; lug  352 ; stepped recess  36 ; stop face  361 ; pivot  362 ; button  37 ; resilient tab  371 ; engaging teeth  372 ; path  373 ; cover  38 ; second space  381 ; buffering unit  39 ; damp member  391 ; gear  391   
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to the drawings wherein the same numeral represents the same component. The description hereinafter is based on embodiments of the present application and are not restricted thereto. 
     Referring to  FIGS.  1  to  12   , the quickly installed headrest adjustment device of the present invention comprises a mount case which is connected to a chair back  100  and includes a recessed area  12 , an engaging hole  13 , a latch  14  and a first contact face  11  which is located on the rear side of the chair back  100 . The recessed area  12  is defined in the first contact face  11  and includes an inner bottom  121 , two side slots  122  and an inner side  123  which extends from the lower end of the inner bottom  121  of the recessed area  12 . The engaging hole  13  is located between the two side slots  122  and defined through the inner bottom of the recessed area. The latch  14  is connected to the inner top side of the engaging hole  13  and includes a bottom face  141  which protrudes beyond the engaging hole  13  and faces the inner side  123  of the recessed area  12 . 
     A headrest unit  20  includes a rail  21  and a headrest  22  that is connected to one end of the rail  21 . The rail  21  includes a groove  211 , and a first gear rack  2111  is located on one side of the groove  211 . 
     An adjustment device  30  is mounted to the rail  21  and includes a second contact face  31 , two ridges  32 , a block  34 , a first space  35 , a stepped recess  36  and a button  37 . The second contact face  31  faces the first contact face  11 . The two ridges  32  protrude beyond the second contact face  31  and are connected to the first contact face  11 . Each ridge  32  has multiple tongues  321  that faces the side slot  122  corresponding thereto. The block  34  is located between the two ridges  32 . The multiple tongues  321  of each of the ridges  32  are inserted into the side slot  122  corresponding thereto so that the ridges  32  are located in the recessed area  12  and contact the inner side  123  of the recessed area  12 . The latch  14  is pushed by the block  34 , and the bottom face  141  of the latch  14  contacts the block  34 . The first space  35  faces the rail  21 . The stepped recess  36  is defined in one side of the first space  35  and includes a stop face  361  and a pivot  362 . The button  37  is pivotably connected to the pivot  362  and includes a resilient tab  371  and multiple engaging teeth  372  which are located on the lower section of the button  37  and face the first gear rack  2111 . The resilient tab  371  extends from the upper section of the button  37  and resiliently contacts the stop face  361 . The button  37  is pivoted by the resilient tab  371  to engage the engaging teeth  372  of the button  37  with the first gear rack  2111 . The button  37  is pushed and pivoted in an opposite direction to disengage the engaging teeth  372  of the button  37  from the first gear rack  2111  of the rail  21  so that the rail  21  is movable up and down along the adjustment device  30 . 
     As shown in  FIGS.  2  to  6   , by the mount case  10  on the chair back  100  that includes the recessed area  12  and the latch  14 . The recessed area  12  includes inner bottom  121  and the two side slots  122 . The latch  14  includes the bottom face  141 . As shown in  FIG.  4   , the adjustment device  30  on the rail  21  includes the block  34  and the two ridges  32 . The two ridges  32  are inserted into the recessed area  12  and move along the direction shown by the arrow head. As shown in  FIG.  5   , the block  34  pushes and deforms the latch  14  which is pivoted so that the adjustment device  30  contacts the inner side  123  and is positioned. The latch  14  is pushed by the block and resiliently moves back, and the bottom face  141  contacts the block  34 , so that the latch  14  is positioned so as to restrict the adjustment device  30  from being disengaged. After the users open the pack box, the rail  21  is installed by slidably connecting the adjustment device  30  to the recessed area  12  of the mount case  10  to quickly complete the installation as shown in  FIG.  6   . 
     As shown in  FIGS.  1  to  12   , the latch  14  includes an inclined face  142  that faces the first contact face  11  and is formed with the bottom face  141 . The inclined face  142  is configured to provide a buffering feature when the block  34  is moved to push and deform the latch  14  to enter into the engaging hole  13 . In addition, the mount case  10  includes multiple through holes  15  which are defined through the inner bottom  121  of the recessed area  12  so as to be connected to the chair back  100 . Each through hole  15  includes a circular recess  151  that is formed in the inner bottom  121  of the recessed area  12  so as to accommodate heads of screws such that the heads of the screws do not protrude beyond the inner bottom  121  of the recessed area  12  to case interference. 
     As shown in  FIG.  7   , the adjustment device  30  includes a notch  33  which accommodates the latch  14  when the latch  14  is deformed to release the block  34 . Therefore, the headrest unit  20  can be released from the chair back  100 . 
     The button  37  is an inverted L-shaped button and includes a path  373  which is located at the upper section of the button  37 . The pivot  362  is pivotably engaged with the path  373 . The quickly installed headrest adjustment device of the present application further comprising a cover  38  which includes a second space  381 . The rail  21  is located between the second space  381  of the cover  38  and the first space  35  of the adjustment device  30 . The groove  21  of the rail  21  includes a second gear rack  2112  which is located corresponding to the first gear rack  2111 . Two guide plates  2113  are axially located between the first gear rack  2111  and the second gear rack  2112 . The first space  35  includes an inner bottom  351 . A lug  352  extends from the inner bottom  351  of the first space  35  and is inserted into the groove  211  of the rail  21 . The lug  352  is engaged between the two guide plates  2113  so as to guide the rail  21  along the adjustment device  30  stably. As an embodiment, the present application further includes a buffering unit  39  which is inserted in the groove  211  of the rail  21  and located between the first gear rack  2111  and the second gear rack  2112 . The buffering unit  39  includes a damp member  391  and a gear  392 . The damp member  391  is fixed to the inner bottom  351  of the first space  35 . The gear  392  is pivotably connected between the damp member  391  and the second gear rack  2112 . The gear  392  is engaged with the second gear rack  2112  and contacts the damp member  391  so that when the second gear rack  2112  of the rail  21  moves up and down to rotate the gear  392 . The gear  392  contacts the damp member  391  to create friction to buffer movement of the second gear rack  2112  of the rail  21 . Besides. the first space  35  includes two hooks  353  to which the damp member  391  is mounted, and a rod  354  to which the gear  392  is pivotably mounted. The two hooks  353  and the rod  354  are formed to the inner bottom  351  of the first space  35 . 
     As shown in  FIG.  13   , the headrest unit  20  includes a guide member  23  which is pivotably connected to the headrest  22 . The rail  21  includes a reception recess  212  defined in the top thereof. A bolt  213  is radially connected to the reception recess  212 . The guide member  23  includes a lateral recess  231 , an insertion  232  facing the reception recess  212 , a protrusion  233  and a spring  234 . The protrusion  233  protrudes from the insertion  232  and the spring  234  is mounted to the protrusion  232 . The reception recess  212  receives the guide member  23 . The spring  234  is biased between the insertion  232  and the inner end of the reception recess  212  to resiliently move the headrest  22  along the reception recess  212 . The bolt  213  protrudes into the lateral recess  231  to prevent the guide member  23  from disengaging from the lateral recess  231 . 
     INDUSTRIAL APPLICABILITY 
     The quickly installed headrest adjustment device of the present application includes a mount case on the chair back, and the mount case includes a recessed area with restriction structure and which allows the users to quickly install the rail to a chair back by connecting the adjustment device to the recessed area of the mount case after the users open the pack box. The present application is convenient and can be manufactured and used in industries.
         A quickly installed headrest adjustment device comprising:   a mount case connected to a chair back and including a recessed area, an engaging hole, a latch and a first contact face which is located on a rear side of the chair back, the recessed area defined in the first contact face and including an inner bottom, two side slots and an inner side which extends from a lower end of the inner bottom of the recessed area, the engaging hole located between the two side slots and defined through the inner bottom of the recessed area, the latch connected to an inner top side of the engaging hole and including a bottom face which protrudes beyond the engaging hole and faces the inner side of the recessed area;   a headrest unit including a rail and a headrest that is connected to one end of the rail, the rail including a groove, a first gear rack located on a side of the groove, the first gear rack including multiple first teeth spaced apart from each other, and   an adjustment device mounted to the rail and including a second contact face, two ridges, a block, a first space, a stepped recess and a button, the second contact face facing the first contact face, the two ridges protruding beyond the second contact face and connected to the first contact face, each ridge having multiple tongues that faces the side slot corresponding thereto, the block located between the two ridges, the multiple tongues of each of the ridges inserted into the side slot corresponding thereto so that the ridges are located in the recessed area and contact the inner side of the recessed area, the latch being pushed by the block and the bottom face of the latch contacting the block, the first space facing the rail, the stepped recess defined in one side of the first space and including a stop face and a pivot, the button pivotably connected to the pivot and including a resilient tab and multiple engaging teeth which are located on a lower section of the button and face the first gear rack, the resilient tab extending from an upper section of the button and resiliently contacting the stop face, the button being pivoted by the resilient tab to engage the engaging teeth of the button with the first teeth of the first gear rack to restrict the rail from being lowered, the rail adjustably moves upward when the first teeth of the first tear rack push upward and are separated from the engaging teeth, the button being pushed and pivoted in an opposite direction to disengage the engaging teeth of the button from the first gear rack of the rail so that the rail is movable down along the adjustment device.