Patent Publication Number: US-2011076164-A1

Title: Air compressor having tilted piston

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an air compressor, and more particularly to an air compressor having a tilted piston for effectively compressing or pumping the air in the pumping movement or stroke and/or for suitably increasing the compressing or pumping effect or operation to the air. 
     2. Description of the Prior Art 
     Typical air compressors comprise a cylinder housing attached or secured to a base and having a piston slidably disposed therein, and a motor secured to the base and coupled to the piston of the cylinder housing for actuating or driving the piston of the cylinder housing in a reciprocating action, in order to generate a pressurized air of a greater air pressure and a decreased flowing quantity and for supplying the pressurized air to inflate various air facilities, such as tires, air beds, air cushions, hovercrafts, etc. 
     The cylinder housing normally includes an outlet tube having one or more outlet ports for selectively attaching and securing or coupling various parts or elements or attachments or facilities, such as the pressure gauges, the air nozzles, the relief valves, the safety valves or the like. 
     The applicant has developed various kinds of typical air compressors, including at least U.S. Pat. No. 6,213,725 to Chou, U.S. Pat. No. 6,514,058 to Chou, U.S. Pat. No. 6,655,928 to Chou, U.S. Pat. No. 6,846,162 to Chou, U.S. Pat. No. 7,240,642 to Chou, and U.S. Pat. No. 7,462,018 to Chou each of which also comprise a piston slidably disposed within a cylinder housing, a spring valve having one end secured to the piston and having the other end for selectively blocking an air aperture of the piston, in order to control the air to flow through the piston, and a motor secured to the base and coupled to the piston of the cylinder housing for actuating or driving or forcing the piston of the cylinder housing to move in the reciprocating action relative to the cylinder housing. 
     Normally, an eccentric member is rotatably attached to the cylinder housing or a supporting plate and coupled to the piston for actuating or driving or forcing the piston to move relative to the cylinder housing, and the piston will be tilted relative to the cylinder housing particularly when the piston is forced to move into the cylinder housing in the compressing or pumping movement or stroke. 
     However, all the pistons of prior arts include a piston rod extended therefrom, the piston rod includes a longitudinal axis and a lateral axis perpendicular with each other and passing through the orifice of the piston rod, but the piston is always parallel to the lateral axis and is simultaneously perpendicular to the longitudinal axis, while in use, particularly when the piston is forced to move into the cylinder housing in the compressing or pumping movement or stroke, the piston will be tilted relative to the cylinder housing and may not effectively compress or pump the air in the pumping movement or stroke. 
     The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional pistons for the air compressors. 
     SUMMARY OF THE INVENTION 
     The primary objective of the present invention is to provide an air compressor including a tilted piston for effectively compressing or pumping the air in the pumping movement or stroke and/or for suitably increasing the compressing or pumping effect or operation to the air. 
     In accordance with one aspect of the invention, there is provided an air compressor comprising a cylinder housing including a chamber formed therein, and including an inner peripheral surface formed therein, and including an outlet tube having a compartment formed therein and communicating with the chamber of the cylinder housing for receiving a pressurized air from the chamber of the cylinder housing, and including a supporting plate, and including a longitudinal axis Z, a piston slidably received in the chamber of the cylinder housing and having a piston rod extended therefrom, the piston rod including a longitudinal axis L and a lateral axis T perpendicular with each other, and the piston being tilted relative to the longitudinal axis L and the lateral axis T of the piston rod, and a motor attached to the supporting plate and coupled to the piston for moving the piston relative to the cylinder housing in a reciprocating action in order to generate the pressurized air. 
     The piston is tilted relative to the lateral axis T of the piston rod for a non-zero angle θ ranged between 0 and 45 degrees (0°&lt;θ&lt;45°, and preferably ranged between 2 and 10 degrees (2°&lt;θ&lt;10°), the piston rod is tilted relative to the longitudinal axis Z of the cylinder housing, and the piston is arranged to be perpendicular to the longitudinal axis Z and the inner peripheral surface of the cylinder housing when the piston is moved toward the outlet tube in a pumping stroke for effectively compressing and pumping an air in the chamber of the cylinder housing. 
     The cylinder housing includes an end surface formed therein and tilted relative to the longitudinal axis Z and the inner peripheral surface of the cylinder housing. The piston includes an air passage formed therein, and includes a valve device attached to the piston for biasing and blocking the air passage of the piston and for controlling the air to flow through the air passage of the piston. The valve device includes a first side attached to the piston, and a second side movable away from the piston. 
     The valve device includes an opening form in the second side thereof, and the piston includes a limiting device extended from the piston and extended through the opening of the valve device for engaging with the second side of the valve device and for limiting the second side of the valve device to move relative to the piston, and for preventing the second side of the valve device from being over bent relative to the valve device. The cylinder housing includes a cavity formed therein for selectively receiving and engaging with the limiting device. 
     The cylinder housing includes a valve seat provided in the outlet tube and located between the outlet tube and the cylinder housing, and a spring-biased check valve disposed in the outlet tube and engaged with the valve seat to limit the pressurized air to flow from the chamber of the cylinder housing into the compartment of the outlet tube only, and to prevent the pressurized air from flowing backwardly from the compartment of the outlet tube into the chamber of the cylinder housing. 
     The motor includes a spindle extended through the supporting plate, and an eccentric member coupled to the spindle and having a pin coupled to the piston rod for moving the piston relative to the cylinder housing. The supporting plate includes a gear rotatably attached thereto and having a space formed by a peripheral casing to receive the eccentric member. 
     The cylinder housing includes a first duct, a second duct, and at least one third duct extended outwardly from the outlet tube and communicating with the compartment of the outlet tube for receiving the pressurized air from the outlet tube, a pressure gauge attached to the first duct, a nozzle coupled to the second duct, and a relief valve attached to the at least one third duct. 
     Further objectives and advantages of the present invention will become apparent from a careful reading of the detailed description provided hereinbelow, with appropriate reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a partial exploded view of an air compressor in accordance with the present invention; 
         FIG. 2  is a perspective view of the air compressor; 
         FIG. 3  is a plan schematic view of the air compressor, in which a portion of the air compressor has been cut off for showing the inner structure of the air compressor; 
         FIG. 4  is another plan schematic view similar to  FIG. 3 , illustrating the operation of the air compressor; 
         FIG. 5  is a further plan schematic view illustrating the supporting base and the cylinder housing of the air compressor; 
         FIG. 6  is a still further plan schematic view as seen from the other direction of the supporting base and the cylinder housing of the air compressor; 
         FIG. 7  is a perspective view illustrating the piston and the piston rod of the air compressor; 
         FIG. 8  is another perspective view similar to  FIG. 7 , illustrating the operation of the piston for the air compressor; 
         FIG. 9  is a partial cross sectional view of the piston and the piston rod, taken along lines  9 - 9  of  FIG. 7 ; 
         FIG. 10  is a plan schematic view of the piston and the piston rod; 
         FIGS. 11 ,  12 ,  13 ,  14 ,  15 ,  16  are plan schematic views similar to  FIG. 3 , illustrating the operation of the air compressor; 
         FIG. 17  is a further partial exploded view illustrating the other arrangement of the air compressor; 
         FIG. 18  is a perspective view of the air compressor as shown in  FIG. 17 ; and 
         FIG. 19  is a partial exploded view illustrating the further arrangement of the supporting base and the cylinder housing for the air compressor. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to the drawings, and initially to  FIGS. 1-6 , an air compressor in accordance with the present invention comprises a supporting base  10  including a supporting plate  11  and a cylinder housing  20  provided on or extended from the supporting plate  11  and preferably, but not necessarily formed integral with the supporting plate  11 , for example, the supporting plate  11  and the cylinder housing  20  may be formed integral with each other with the molding or mold-injection processes as shown in  FIGS. 1-6 , or alternatively, as shown in  FIG. 19 , the cylinder housing  200  may include one or more projections  201  extended therefrom and engaged with corresponding hubs or tubular members  111  of the supporting plate  110  for detachably attaching or mounting or securing the cylinder housing  200  to the supporting plate  110 . 
     As also shown in  FIGS. 1-6 , the supporting plate  11  includes two holes  12 ,  13 , such as an upper hole  12  and a lower hole  13  formed therein, in which the upper hole  12  of the supporting plate  11  is located closer to the cylinder housing  20 , and the lower hole  13  of the supporting plate  11  is located distal or farther away from the cylinder housing  20 . The cylinder housing  20  includes a chamber  21  formed therein and formed or defined by an inner peripheral surface  22  for slidably receiving or engaging with a piston  30  therein, the piston  30  includes an extension or piston rod  31  extended therefrom and is slidable in a reciprocating action in the chamber  21  of the cylinder housing  20  for generating pressurized air. 
     The cylinder housing  20  includes an outlet tube  15  extended upwardly or outwardly from the top thereof, and having a compartment  16  formed therein ( FIGS. 3-4 ,  11 - 16 ) and communicating with the chamber  21  of the cylinder housing  20 , for receiving the pressurized air from the chamber  21  of the cylinder housing  20 . A spring-biased check valve  17  ( FIGS. 3-4 ,  11 - 16 ) may be disposed in the outlet tube  15 , and engaged with a valve seat  18  that is formed or provided between the outlet tube  15  and the cylinder housing  20 . A relief valve or safety valve (not shown) or the like may further be provided and attached to the outlet tube  15 , for relieving the pressurized air when the air pressure within the cylinder housing  20  and the outlet tube  15  is over a predetermined value. 
     The spring-biased check valve  17  may thus be used to limit and to guide the pressurized air to flow only from the chamber  21  of the cylinder housing  20  into the compartment  16  of the outlet tube  15 , and to prevent the pressurized air from flowing backwardly from the compartment  16  of the outlet tube  15  into the chamber  21  of the cylinder housing  20 . A cap  19  may further be provided and attached to the outer or free end of the outlet tube  15  with such as a threading engagement (not shown) for blocking or enclosing or sealing the compartment  16  of the outlet tube  15 , and for stably retaining the spring-biased check valve  17  within the compartment  16  of the outlet tube  15 . 
     The cylinder housing  20  further includes one or more ducts  23 ,  24 ,  25 ,  26  extended outwardly from the outlet tube  15 , and communicating with the compartment  16  of the outlet tube  15 , for receiving the pressurized air from the compartment  16  of the outlet tube  15 . The ducts  23 ,  24 ,  25 ,  26  may be coupled to various kinds of facilities that require pressurized air supplied thereto. For example, a relief valve  27  ( FIG. 19 ) may be provided and attached to one of the ducts  23  for relieving the pressurized air when the air pressure within the cylinder housing  20  and/or the outlet tube  15  is over a predetermined pressure, and thus for preventing the cylinder housing  20  and/or the outlet tube  15  from being over-pressurized and damaged. 
     A pressure gauge  28  may be provided and attached to the other duct  24  for detecting and showing the air pressure within the cylinder housing  20  and/or the outlet tube  15 . A nozzle  29  may be provided and attached to another duct  26  for allowing the pressurized air to be supplied from the chamber  21  of the cylinder housing  20  and the compartment  16  of the outlet tube  15  to various pneumatic facilities that require pressurized air supplied thereto, with the nozzle  29 . A relief valve or safety valve  14  or the like may further be provided and attached to the other duct  25 , for relieving the pressurized air when the air pressure within the cylinder housing  20  and the outlet tube  15  is over a predetermined value. 
     It is to be noted that the provision or the extension of the ducts  23 ,  24 ,  25 ,  26  from the outlet tube  15  allows the relief valve  27  and the pressure gauge  28  and the nozzle  29  to be easily and readily attached to or coupled to the outlet tube  15  with the ducts  23 ,  24 ,  25 ,  26 , without additional or specialized coupling members or tools. One or more lids (not shown) may further be provided and attached or secured to either of the ducts  23 ,  24 ,  25 ,  26  with such as a threading engagement, for selectively enclosing or blocking the ducts  23 ,  24 ,  25 ,  26 , when the ducts  23 ,  24 ,  25 ,  26  are not required to be used, or when the relief valve  27  and the pressure gauge  28  and the nozzle  29  are not attached or secured to the ducts  23 ,  24 ,  25 ,  26 . 
     A gear  40  is rotatably attached to the lower portion of the supporting plate  11  with one or more bearings (not shown) and a shaft  41 , and includes a space  43  formed therein and defined by a peripheral casing  44  for receiving and securing an eccentric member  45  therein. The eccentric member  45  may be secured to the gear  40  with such as fasteners (not shown) or with the molding or mold-injection processes and may thus be rotated in concert with the gear  40 , and includes a crank or an eccentric pin  46  extended therefrom and coupled to the piston rod  31  of the piston  30 , such as coupled to an orifice  39  of the piston rod  31  in order to actuate or to move the piston  30  relative to the cylinder housing  20  in reciprocating actions, the piston rod  31  includes a longitudinal axis L and a lateral axis T perpendicular with each other and passing or extended through the orifice  39  of the piston rod  31 . 
     A motor  47  may be attached or secured to the upper portion of the supporting plate  11  with such as fasteners (not shown), and includes a spindle  48  extended through the upper hole  12  of supporting plate  11  ( FIG. 2 ), and includes a pinion  49  secured to the spindle  48  thereof, and engaged with the gear  40 , for allowing the gear  40  to be rotated or driven by the motor  47  with the pinion  49 , and thus for allowing the piston  30  to be actuated or moved relative to the cylinder housing  20  in reciprocating actions by the eccentric member  45  and the eccentric pin  46 . A fan device  42  may further be provided and coupled to the motor  47  for being rotated or driven by the motor  47  to generate circulating or ventilating air. 
     In operation, as shown in  FIGS. 3 and 4 , the piston  30  may be actuated or moved relative to the cylinder housing  20  in reciprocating actions by the motor  47  with the pinion  49 , the gear  40 , the eccentric member  45  and the eccentric pin  46 , in order to generate a pressurized air, and to allow the pressurized air to flow into the outlet tube  15 , and then to flow out through either or all of the ducts  23 ,  24 ,  25 ,  26 , and thus to allow the air pressure within the cylinder housing  20  and/or the outlet tube  15  to be detected and shown by the pressure gauge  28 , and to allow the pressurized air to be supplied into the facilities that require pressurized air supplied thereto, with the nozzle  29 , and/or to allow the pressurized air to be relieved via the relief valve  27  when the cylinder housing  20  and/or the outlet tube  15  is over-pressurized. 
     Alternatively, as shown in  FIGS. 17 and 18 , another motor  471  of different dimension or power may be changeably attached or secured to the supporting plate  11  and extended through the lower hole  13  of supporting plate  11  and directly attached or mounted or secured to the eccentric member  450  with such as fasteners  451  for directly actuating or rotating or driving the eccentric member  450  to rotate relative to the cylinder housing  20  in reciprocating actions without the gear  40 . The above-described structure including the supporting base  10 , the supporting plate  11 , the cylinder housing  20 , the pressure gauge  28 , the nozzle  29 , the motor  471  and the eccentric member  450  is typical and will not be described in further details. 
     As shown in  FIGS. 3-4  and  7 - 10 , the piston  30  preferably includes a sealing ring  32  attached to the outer peripheral portion thereof and slidably engaged with the cylinder housing  20 , for making an air tight seal between the piston  30  and the cylinder housing  20 ; and includes an air passage  33  formed therein. A spring blade or valve device  60  includes one or first side  61  attached or secured to one or first side  34  of the piston  30  with one or more latch pins or fasteners  62 , and includes a suitable resilience for biasing and blocking the air passage  33  of the piston  30  and for controlling the air to selectively flow through the air passage  33  of the piston  30 . The valve device  60  further includes an opening  63  form in the second side  64  of the valve device  60  and located opposite to or distal to the first side  61  of the valve device  60  and the fasteners  62 , in which the second side  64  of the valve device  60  is movable away from the piston  30 . 
     The valve device  60  is made of resilient metal or steel materials and may be forced to be bent relative to the piston  30  in order to block and to selectively open the air passage  33  of the piston  30  and to allow the air to flow through the piston  30  at one time when the air passage  33  of the piston  30  is partially opened by the spring blade or valve device  60 . The piston  30  includes a limiting device or projection  35  extended upwardly from the second side  36  of the piston  30  and located opposite to the first side  61  of the valve device  60  and the fasteners  62 , and preferably arranged to have the air passage  33  of the piston  30  formed and located between the fasteners  62  and the limiting device or projection  35 . 
     The limiting device or projection  35  is extended through the opening  63  of the valve device  60  for engaging with the second side  64  of the valve device  60 , and thus for limiting the second side  64  of the valve device  60  to bend or to move relative to the piston  30 , and for preventing the second side  64  of the valve device  60  from being over bent or deformed relative to the first side  61  of the valve device  60 . The fasteners  62  and the limiting device or projection  35  are particularly designed and provided for engaging with the valve device  60  as shown in FIGS.  4  and  7 - 9 , and for preventing the valve device  60  from being over bent or deformed relative to the first side  61  of the valve device  60 . The other valve devices may be attached to the piston  30  without the fasteners  62  and the limiting device or projection  35 . 
     As also shown in FIGS.  4  and  7 - 10 , the piston  30  is arranged and tilted relative to the longitudinal axis L or the lateral axis T of the piston rod  31  for a non-zero angle θ ranged between 0 and 45 degrees (0°&lt;θ&lt;45°, and preferably ranged between 2 and 10 degrees (2°&lt;θ&lt;10°, and/or the piston  30  includes a flat surface or an actuating surface  37  tilted relative to the longitudinal axis L or the lateral axis T of the piston rod  31  for the non-zero angle θ for allowing the piston  30  and/or the actuating surface  37  of the piston  30  to be perpendicular to the longitudinal axis Z of the cylinder housing  20  or to be parallel to the lateral axis X of the cylinder housing  20  when the piston  30  is moved toward the outlet tube  15  in the pumping movement or stroke or operation, at this moment, the piston rod  31  is tilted relative to the longitudinal axis Z of the cylinder housing  20 , but the piston  30  and/or the actuating surface  37  of the piston  30  is perpendicular to the longitudinal axis Z of the cylinder housing  20  or to be parallel to the lateral axis X of the cylinder housing  20 , best shown in  FIG. 12 . It is preferable that the non-zero angle θ is greater when the piston rod  31  is shorter, and is smaller when the piston rod  31  is longer relatively. 
     As shown in  FIGS. 3-4  and  11 - 16 , it is preferable that the cylinder housing  20  includes an inclined upper or top or end surface  70  formed therein and tilted or inclined relative to the longitudinal axis Z or the lateral axis X of the cylinder housing  20  and also tilted or inclined relative to the inner peripheral surface  22  of the cylinder housing  20 , and further includes one or more, such as two or more cavities  71 ,  72  formed therein for selectively receiving or engaging with the fasteners  62  and the limiting device or projection  35  when the piston  30  is completely moved into the chamber  21  of the cylinder housing  20  ( FIGS. 13 ,  14 ). The inclined upper or end surface  70  of the cylinder housing  20  is arranged to be parallel to the upper actuating surface  37  of the piston  30  when the piston  30  is completely moved into the chamber  21  of the cylinder housing  20  at the top dead position ( FIG. 14 ). 
     In operation, as shown in  FIG. 11 , the actuating surface  37  of the piston  30  is tilted relative to the longitudinal axis Z and the inner peripheral surface  22  or the lateral axis X of the cylinder housing  20 , and the piston rod  31  is substantially parallel to the longitudinal axis Z or perpendicular to the lateral axis X of the cylinder housing  20  when the piston  30  is moved away from the outlet tube  15  and the upper or end surface  70  of the cylinder housing  20  at the lowest dead position. As shown in  FIG. 12 , when the piston  30  is moved toward the outlet tube  15  in the pumping movement or stroke or operation, the piston rod  31  will be tilted relative to the longitudinal axis Z of the cylinder housing  20 , and the actuating surface  37  of the piston  30  will be perpendicular to the longitudinal axis Z and the inner peripheral surface  22  and parallel to the lateral axis X of the cylinder housing  20  such that the piston  30  may effectively compress or pump the air in the chamber  21  of the cylinder housing  20  and in the pumping movement or stroke in order to suitably increase the compressing or pumping effect or operation to the air. 
     As shown in  FIGS. 13 and 14 , when the piston  30  is completely moved into the chamber  21  of the cylinder housing  20 , the upper actuating surface  37  of the piston  30  will be parallel to the upper or end surface  70  of the cylinder housing  20 , at this moment, the fasteners  62  and the limiting device or projection  35  will be selectively received or engaged with the cavities  71 ,  72  of the cylinder housing  20  respectively for allowing the piston  30  to be completely moved into the chamber  21  of the cylinder housing  20  at the top dead position where the piston rod  31  is substantially parallel to the longitudinal axis Z or perpendicular to the lateral axis X of the cylinder housing  20  again. 
     As shown in  FIGS. 15 and 16 , in the relieving or air intake stroke, the piston rod  31  will be tilted relative to the longitudinal axis Z or the lateral axis X of the cylinder housing  20 , and the actuating surface  37  of the piston  30  will also be tilted relative to the longitudinal axis Z or the lateral axis X of the cylinder housing  20  and will substantially parallel to the upper or end surface  70  of the cylinder housing  20  at this moment, such that the piston  30  may be arranged to be perpendicular to the longitudinal axis Z and the inner peripheral surface  22  and parallel to the lateral axis X of the cylinder housing  20  when the piston  30  is moved toward the outlet tube  15  in the pumping movement or stroke or operation, and such that the piston  30  may be used to effectively compress or pump the air in the chamber  21  of the cylinder housing  20  and in the pumping movement or stroke in order to suitably increase the compressing or pumping effect or operation to the air. 
     Accordingly, the air compressor in accordance with the present invention includes a tilted piston for effectively compressing or pumping the air in the pumping movement or stroke and/or for suitably increasing the compressing or pumping effect or operation to the air. 
     Although this invention has been described with a certain degree of particularity, it is to be understood that the present disclosure has been made by way of example only and that numerous changes in the detailed construction and the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention as hereinafter claimed.