Patent Publication Number: US-11039683-B2

Title: Height adjustable table

Description:
RELATED APPLICATIONS 
     This application is based on and claims the benefit of priority from Chinese Patent Application No. 2019102414926, filed on Mar. 28, 2019, the entirety of which is incorporated by reference herein. 
     FIELD 
     This invention relates to the field tables, and in particular to a height adjustment mechanism for a height adjustable table. 
     BACKGROUND 
     In typical height adjustable tables, a gas spring is generally used to drive an inner sleeve to slide vertically within an outer sleeve. After the gas spring is driven, original air pressure is generally used to hold the table height at a fixed position. However, if the air is discharged, this may result in instability of the table and affect its use. 
     SUMMARY 
     The present disclosure provides a height adjustment mechanism and a table that address the technical problems in the prior art. The working state of the height adjustment mechanism can be locked to ensure normal use of the table. 
     According to a first aspect of the present disclosure, a height adjustment mechanism is provided, including an outer sleeve, an inner sleeve, a plug, and a locking mechanism. The outer sleeve is disposed outside the inner sleeve, and the outer sleeve and the inner sleeve are relatively slidable. The plug is disposed outside the inner sleeve and is slidably connected to the inner sleeve. The plug is disposed at an upper end of the outer sleeve, and an outer wall of the plug includes a pressing portion. The locking mechanism is used to press the pressing portion tightly against an outer wall of the inner sleeve. 
     The present disclosure has the following beneficial effects. The locking mechanism presses the pressing portion against the outer wall of the inner sleeve to increase the friction between the plug and the inner sleeve, so that the plug and the inner sleeve are relatively fixed. The plug is disposed at the upper end of the outer sleeve, and when the plug abuts against a top end of the outer sleeve, the entire height adjustment mechanism can be locked. This ensures that the outer sleeve and the inner sleeve are prevented from continuing to slide relative to each other, and the table is steady and stable and normal use thereof is ensured. 
     In the height adjustment mechanism according to the first aspect of the present disclosure, the plug is embedded in the outer sleeve, the outer sleeve includes a concave hole, the locking mechanism includes a cam that is extended into the concave hole and presses the pressing portion to make the pressing portion abut against the inner sleeve. The plug is embedded in the outer sleeve to fix the positions of the plug and the outer sleeve relative to each other, the pressing portion is then aligned with the concave hole, and the cam extends into the concave hole to press the pressing portion tightly. 
     In the height adjustment mechanism according to the first aspect of the present disclosure, the outer sleeve includes a cam base, and the cam is rotatably connected to the cam base. The cam is rotated to enable the height adjustment mechanism to switch between a locked state and a movable state. 
     In the height adjustment mechanism according to the first aspect of the present disclosure, the outer sleeve is fixedly connected to the plug by a pin. The plug is fixed on the outer sleeve to prevent the plug from moving as the inner sleeve retracts, so that it can be ensured that the relative position between the plug and the outer sleeve is fixed to facilitate use. 
     In the height adjustment mechanism according to the first aspect of the present disclosure, a plurality of protrusions are provided at an inner side surface of the plug, and a plurality of grooves are provided at the surface of the inner sleeve for accommodating the protrusions. The protrusions are embedded in the grooves and slide in the grooves to guide the inner sleeve, thereby preventing relative rotation between the inner sleeve and the plug to reduce shaking. 
     In the height adjustment mechanism according to the first aspect of the present disclosure, at least one guide sleeve is disposed between the inner sleeve and the outer sleeve, and the guide sleeve disposed at the lowest end is fixedly connected to a lower end of the inner sleeve. The guide sleeve is disposed between the inner sleeve and the outer sleeve to prevent friction there between, so as to protect the surface of the inner sleeve and facilitate the slide of the inner sleeve in the outer sleeve. 
     In the height adjustment mechanism according to the first aspect of the present disclosure, the guide sleeve includes a plurality of through holes in which a plurality of ball bearings are embedded, and the ball bearings abut against the inner sleeve and the outer sleeve. The ball bearings convert sliding friction into rolling friction to reduce the overall friction. In addition to rolling in the holes, the ball bearings can also move inward or outward in the holes when being elastically compressed, thereby avoiding hindered and unsmooth sliding caused by insufficient roundness or uneven thickness of the outer sleeve when the inner sleeve moves in the outer sleeve. The roundness herein is defined as a radial offset of an actual contour relative to a perfect circle, that is, a difference between a maximum radius and a minimum radius relative to the same center of circle. 
     The height adjustment mechanism according to the first aspect of the present disclosure further includes a base and a mounting frame, wherein the base is fixed at a bottom end of the outer sleeve, the mounting frame is fixed at a top end of the inner sleeve, a gas spring is disposed inside the inner sleeve, and two ends of the gas spring are separately fixed on the mounting frame and the base. The gas spring supplies lifting force to the inner sleeve. 
     In the height adjustment mechanism according to the first aspect of the present disclosure, the mounting frame includes a fixing base, a rotating frame, and a rotating handle. The fixing base is fixed at the top end of the inner sleeve, an end of the rotating frame is rotatably connected to the fixing base, and an end of the rotating handle is rotatably connected to a free end of the rotating frame. The fixing base includes a concave portion in which a free end of the rotating handle is inserted to fix the position of the rotating handle. The rotating frame is vertically disposed when the rotating handle is inserted in the concave portion. 
     A second aspect of the present disclosure provides a table that includes any of the height adjustment mechanisms. 
     The present disclosure has the following beneficial effects. The locking mechanism presses the pressing portion against the outer wall of the inner sleeve to increase the friction between the plug and the inner sleeve, so that the plug and the inner sleeve are relatively fixed. The plug is disposed at the upper end of the outer sleeve, and when the plug abuts against a top end of the outer sleeve, the entire height adjustment mechanism can be locked to ensure that the outer sleeve and the inner sleeve are prevented from sliding relative to each other. This ensures that the table is steady and stable in normal use. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other embodiments of the invention will become apparent by reference to the detailed description in conjunction with the figures, wherein elements are not to scale so as to more clearly show the details, wherein like reference numbers indicate like elements throughout the several views, and wherein: 
         FIG. 1  is a schematic structural diagram of a table according to an embodiment of the present disclosure; 
         FIG. 2  is a schematic structural diagram of a height adjustment mechanism according to an embodiment of the present disclosure; 
         FIG. 3  is a schematic structural diagram of a plug according to an embodiment of the present disclosure; 
         FIG. 4  is a schematic structural diagram of a guide sleeve, an outer sleeve, and an inner sleeve; 
         FIG. 5  is a partial schematic diagram of a portion depicted in  FIG. 4  according to an embodiment of the present disclosure; 
         FIG. 6  is a schematic structural diagram of an inner sleeve, a guide sleeve, and a plug according to an embodiment of the present disclosure; 
         FIG. 7  is a schematic structural diagram of a mounting frame with a rotating frame in a vertical state according to an embodiment of the present disclosure; 
         FIG. 8  is a schematic structural diagram of a mounting frame with a rotating frame in a horizontal state according to an embodiment of the present disclosure; 
         FIG. 9  depicts a plurality of tables are arranged close together according to an embodiment of the present disclosure; and 
         FIG. 10  depicts a table in a folded state according to an embodiment of the present disclosure. 
     
    
    
     REFERENCE NUMERALS 
     
         
         tabletop  10 ; 
         height adjustment mechanism  20 ; 
         outer sleeve  21 ; 
         concave hole  211 ; 
         inner sleeve  22 ; 
         groove  221 ; 
         plug  23 ; 
         pressing portion  231 ; 
         protrusion  232 ; 
         cam  24 ; 
         cam base  241 ; 
         base  25 ; 
         mounting frame  26 ; 
         gas spring  27 ; 
         guide sleeve  28 ; 
         through hole  281 ; 
         ball bearing  282 ; 
         fixing base  262 ; 
         rotating frame  261 ; 
         rotating handle  263 ; 
         abutting block  2631 ; 
         embedding hole  2622 ; 
         concave portion  2621 ; 
         torsion spring  2632 ; and 
         locking mechanism  29 . 
       
    
     DETAILED DESCRIPTION 
     Specific embodiments of the present disclosure are described in detail herein. Preferred embodiments are shown in the accompanying drawings which supplement the textual description in the specification for intuitive and visual understanding of each technical feature and the overall technical solution of the present disclosure, but shall not be understood as a limitation to the scope of the present disclosure. 
     In the description of the present disclosure, it should be understood that orientation and position relationships indicated by “up,” “down,” “front,” “rear,” “left,” “right,” and the like are based on orientation or location relationships shown in the accompanying drawings, and are used only to facilitate and simplify the description of the present disclosure, but are not used to indicate or imply that the apparatuses or elements must have specific orientations, or are constructed and operated by using specific orientations, and therefore, cannot be understood as a limitation to the present disclosure. 
     In the description of the present disclosure, the terms “first” and “second” as used herein are for distinguishing technical features, but are not intended to indicate or imply relative importance or implicitly specify a quantity of indicated technical features or implicitly specify an order of indicated technical features. 
     Unless otherwise expressly defined in the description of the present disclosure, terms such as “disposed,” “mounted,” and “connected” should be understood in a broad sense. For persons of ordinary skill in the art, specific meanings of the terms in the present disclosure may be appropriately determined with reference to the specific content in the technical solution. 
     Referring to  FIG. 1 , a table of a preferred embodiment of the present disclosure includes a tabletop  10  and a height adjustment mechanism  20 . The table in the present disclosure may be any of various types of tables such as a dinner table, a desk, a conference table, a coffee table, a bar table, and a training table. 
     Referring to  FIG. 2  and  FIG. 3 , the height adjustment mechanism  20  in this embodiment of the present disclosure includes an outer sleeve  21 , an inner sleeve  22 , a plug  23 , and a locking mechanism  29 . The outer sleeve  21  is disposed outside the inner sleeve  22 , and the outer sleeve  21  and the inner sleeve  22  are relatively slidable. The plug  23  is disposed outside the inner sleeve  22 , and slidably engages the inner sleeve  22 . The plug  23  is disposed at an upper end of the outer sleeve  21 , and an outer wall of the plug  23  includes a pressing portion  231 . The locking mechanism  29  is used to urge the pressing portion  231  tightly against an outer wall of the inner sleeve  22 . 
     Referring to the embodiment of  FIG. 3 , the plug  23  is made of plastic, and the outer wall of the plug  23  includes two vertical grooves that separate a left side and a right side of the pressing portion  231  from the outer wall. An upper side of the pressing portion  231  is connected to the outer wall, and a connecting portion forms a rotating fulcrum for the pressing portion  231 , to enable the pressing portion  231  to move with respect to the outer wall. 
     During use, the locking mechanism  29  urges the pressing portion  231  against the outer wall of the inner sleeve  22  to increase the friction between the plug  23  and the inner sleeve  22 , so that the plug  23  and the inner sleeve  22  are relatively fixed. The plug  23  is disposed at the upper portion of the outer sleeve  21  and abuts against a top end of the outer sleeve  21 . The relative position between the plug  23  and the outer sleeve  21  is fixed, and therefore the entire height adjustment mechanism  20  can be locked, so that it is ensured that the outer sleeve  21  and the inner sleeve  22  are kept from continuing to slide relative to each other, thereby ensuring that the table is steady and stable during normal use. 
     In some embodiments, the plug  23  may be embedded in the outer sleeve  21 , and the outer sleeve  21  includes a concave hole  211 . In such embodiments, the locking mechanism  29  includes a cam  24  that is extendable into the concave hole  211  to urge the pressing portion  231  to press against the inner sleeve  22 . 
     Referring to  FIG. 1  and  FIG. 2 , in a specific implementation, the outer sleeve  21  includes a cam base  241 . The cam base  241  includes stop blocks disposed on two sides of the concave hole  211 , and the cam  24  is rotatably connected to the stop blocks. When the entire height adjustment mechanism  20  needs to be locked, the cam  24  presses the pressing portion  231  which causes the pressing portion  231  to press the inner sleeve  22  tightly, thereby increasing the friction. When the inner sleeve  22  needs to be raised or lowered, the cam  24  is rotated to reduce the friction between the pressing portion  231  and the inner sleeve  22 , so as to enable the inner sleeve  22  and the plug  23  to be relatively slidable. 
     It should be noted that in another implementation, the cam  24  is replaced by a set screw that engages with the concave hole  211  through threads. When the entire height adjustment mechanism  20  needs to be locked, the set screw is screwed into the inner sleeve  22  and presses the pressing portion  231  tightly against the inner sleeve  22 . When the inner sleeve  22  needs to be raised or lowered, the set screw is screwed out to release the pressing portion  231  and the inner sleeve  22 . 
     Referring to  FIG. 2 , in a specific implementation, the outer sleeve  21  is fixedly connected to the plug  23  by a pin to prevent the plug  23  from moving as the inner sleeve  22  extends and retracts. This ensures that the relative position between the plug  23  and the outer sleeve  21  is fixed to facilitate use. 
     Referring to  FIG. 6 , a plurality of protrusions  232  are provided at an inside surface of the plug  23 , and a plurality of grooves  221  are provided in the outer surface of the inner sleeve  22  for accommodating the protrusions  232 . The protrusions  232  are embedded in the grooves  221  and slide in the grooves  221  to guide the inner sleeve  22 , thereby preventing relative rotation between the inner sleeve  22  and the plug  23 . 
     As shown in  FIG. 3 , three protrusions  232  are evenly disposed around the perimeter of the inside surface of the plug  23 . When engaged with the inner sleeve  22 , the plug  23  can bear more balanced force, thereby making the height adjustment mechanism  20  more stable. One skilled in the art will appreciate that more or fewer than three protrusions  232  may be provided in other embodiments. 
     In a specific implementation depicted in  FIG. 4  and  FIG. 5 , at least one guide sleeve  28  is disposed between the inner sleeve  22  and the outer sleeve  21 . The guide sleeve  28  disposed at the lowest end is preferably fixedly connected to a lower end of the inner sleeve  22 . 
     Referring to  FIG. 5  and  FIG. 6 , the guide sleeve  28  may comprise a first guide sleeve  28 - 1  and a second guide sleeve  28 - 2 . The second guide sleeve  28 - 2  is disposed at the lower end of the inner sleeve  22  and is fixed by a pin. The first guide sleeve  28 - 1  is slidable on the inner sleeve  22 . The second guide sleeve  28 - 2  can effectively prevent the first guide sleeve  28 - 1  from falling off the inner sleeve  22  while sliding. 
     The guide sleeve  28  disposed between the inner sleeve  22  and the outer sleeve  21  can prevent friction between the inner sleeve  22  and the outer sleeve  21 , thus protecting the surface of the inner sleeve  22 . 
     As shown in  FIG. 5 , the guide sleeve  28  may include a plurality of through holes  281  in which a plurality of ball bearings  282  are embedded. The ball bearings  282  abut against the inner sleeve  22  and the outer sleeve  21 . Thus, sliding friction is converted into rolling friction to reduce the overall friction. 
     In a specific implementation, the height adjustment mechanism  20  in the present disclosure further includes a base  25  and a mounting frame  26 . The base  25  is fixed at a bottom end of the outer sleeve  21 , and the mounting frame  26  is fixed at a top end of the inner sleeve  22 . A gas spring  27  is provided inside the inner sleeve  22 . Two ends of the gas spring  27  are separately fixed on the mounting frame  26  and the base  25 . The gas spring  27  provides a lifting force to the inner sleeve  22 . 
     In some embodiments shown in  FIG. 7  and  FIG. 8 , the mounting frame  26  includes a fixing base  262 , a rotating frame  261 , and a rotating handle  263 . The fixing base  262  is fixed at the top end of the inner sleeve  22 , and an end of the rotating frame  261  is rotatably connected to the fixing base  262 . An end of the rotating handle  263  is rotatably connected to a free end of the rotating frame  261 . The fixing base  262  includes a concave portion  2621  in which a free end of the rotating handle  263  may be inserted to fix the position of the rotating handle  263 . When the rotating handle  263  is embedded in the concave portion  2621 , the rotating frame  261  is vertically disposed. The tabletop  10  is fixed on the rotating frame  261 . 
     It should be noted that a torsion spring  2632  is disposed between the rotating handle  263  and the rotating frame  261 . The rotating handle  263  includes an abutting block  2631 . A fixing frame includes an embedding hole  2622  in which the abutting block  2631  may be embedded. The embedding hole  2622  is disposed in a bottom side of the fixing frame. When the rotating handle  263  drives the tabletop  10  to swing downward, the abutting block  2631  is embedded in the embedding hole  2622 . When the tabletop  10  is horizontally placed, the torsion spring  2632  is in a tightened state, so that the embedding hole  2622  abuts against the abutting block  2631  to fix the tabletop  10 . 
     The rotating handle  263  is rotated to manipulate the rotating frame  261  to switch between a horizontal state and a vertical state, making it convenient for a user to turn around the tabletop  10  to facilitate storage.  FIG. 10  is a schematic structural diagram showing a table in a folded state. When the table is turned around and folded, horizontal space needed for storage can be reduced, thereby increasing the space utilization. Referring to  FIG. 9 , for storage purposes, a plurality of tables may be arranged close together to save space. 
     In one preferred embodiment, a table includes a tabletop  10  and a height adjustment mechanism  20 . The height adjustment mechanism  20  includes an outer sleeve  21 , an inner sleeve  22 , a plug  23 , a locking mechanism  29 , a base  25 , and a mounting frame  26 . The outer sleeve  21  is disposed outside the inner sleeve  22 . The outer sleeve  21  and the inner sleeve  22  are slidable relative to each other. The plug  23  is disposed outside the inner sleeve  22  and is slidably connected to the inner sleeve  22 . The plug  23  is disposed at the upper end of the outer sleeve  21 , and the outer wall of the plug  23  includes a pressing portion  231 . The plug  23  is embedded in the outer sleeve  21  and is fixed on the outer sleeve  21  by a pin. The outer sleeve  21  includes a concave hole  211 . The locking mechanism  29  includes a cam  24 . The outer sleeve  21  includes a cam base  241 . The cam base  241  includes stop blocks disposed on two sides of the concave hole  211 . The cam  24  is rotatably connected to the stop blocks. The cam  24  rotates on the cam base  241  and extends into the concave hole  211 . The cam  24  drives the pressing portion  231  to press against the inner sleeve  22 , and the friction between the pressing portion  231  and the inner sleeve is increased to fix the positions of the plug  23  and the inner sleeve relative to each other. A plurality of protrusions  232  are disposed at an inside surface of the plug  23 , and a plurality of grooves  221  are disposed at the surface of the inner sleeve  22  for accommodating the protrusions  232 . At least one guide sleeve  28  is disposed between the inner sleeve  22  and the outer sleeve  21 . The guide sleeve  28  at the lowest end is fixedly connected to a lower end of the inner sleeve. The guide sleeve  28  includes a plurality of through holes  281  in which a plurality of ball bearings  282  are embedded. The ball bearings  282  abut against the inner sleeve  22  and the outer sleeve  21 . The base  25  is fixed at a bottom end of the outer sleeve  21 . The mounting frame  26  is fixed at a top end of the inner sleeve  22 . A gas spring  27  is disposed inside the inner sleeve  22 . Two ends of the gas spring  27  are separately fixed on the mounting frame  26  and the base  25 . 
     The appearances of the plug  23  and the guide sleeve  28  are also configured to be aesthetically pleasing and include various ornamental aspects and features. 
     The foregoing description of preferred embodiments for this invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. The embodiments are chosen and described in an effort to provide the best illustrations of the principles of the invention and its practical application, and to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled.