Patent Publication Number: US-2022228584-A1

Title: Easy-to-assemble air pump

Description:
BACKGROUND 
     The present invention relates to an air pump and, more particular, to an easy-to-assemble air pump with one-piece piston member. 
     A conventional portable air pump, such as the air pump disclosed in Taiwan Patent No. 410912, which includes a pump body, a one-way valve seat, a piston and a pipe body. An outer edge of one end of the pump body is provided with an external threaded portion to screw a pivot seat, and a recess of the pivoting seat accommodates an end of an inner nozzle head. One end of the piston is provided with a threaded portion to be screwed in a screw hole of the pipe body. When assembling the above air pump, the piston and the pipe body must be screwed together first, and the one-way valve seat is placed on the pump body, and then the pivot seat and the external threaded portion of the pump body is screwed together. 
     Furthermore, another common portable air pump  90  shown in  FIG. 4  includes a metal piston rod  91  movably coupled to a cylinder  92  for movement with respect thereto. One end of the metal piston rod  91  is secured with a piston  93  via a rivet connection, and another end of the metal piston rod  91  is connected with a plastic adaptor  94  used to be pivotally coupled with a handle  95 . However, the metal piston rod  91  must be made of metal due to the rivet connection with the piston  93 , and needs the plastic adaptor  94  to indirectly pivotally coupled with the handle  95 . 
     The assembly processes of the above portable air pumps are complicated, in which must to add an assembly step for mounting the piston to the pipe body or piston rod, and the metal piston rod  91  cannot directly pivotally coupled with a plastic handle  95  to further need the plastic adaptor  94 , resulting in higher production costs. 
     Thus, a need exists for a novel air pump to mitigate and/or obviate the above disadvantages. 
     SUMMARY 
     The invention is defined by the feature of the independent claim. Preferred embodiments are defined by the features of the dependent claims. 
     An easy-to-assemble air pump according to the present invention includes a cylinder, a piston member, a valve seat, and a valve connector. The piston member includes a piston portion and a rod portion integrally formed as a monolithic member. The piston portion is axially movably arranged into the cylinder, and the rod portion is movably coupled to the cylinder for movement with respect thereto. The valve seat is arranged in the cylinder. The valve connector is connected to one end of the cylinder. 
     In an embodiment, the cylinder has a first through-hole penetrating a periphery of the cylinder. The valve seat has a second through-hole aligning to the first through-hole. The valve connector has a third through-hole aligning to the second through-hole. A first pin member inserts through the first through-hole, the second through-hole, and the third through-hole. 
     In an embodiment, the first pin member has a communicating bore interconnected with the cylinder and the valve connector. 
     In an embodiment, the easy-to-assemble air pump further includes a handle and a second pin member. One end of the cylinder opposite to the valve seat is provided with an end cap. The rod portion has a pivotal end extending out of the end cap and a first pivotal hole provided at the pivotal end. The handle has a second pivotal hole aligning to the first pivotal hole. The second pin member inserts through the first pivotal hole and the second pivotal hole, thereby pivotally connecting the handle to the pivotal end. 
     In an embodiment, the end cap is threadedly mounted at one end of the cylinder opposite to the valve seat. 
     In an embodiment, both of the rod portion and the handle are made of plastic material. 
     In an embodiment, the rod portion is hollow and has a thickness greater than 0.6 mm. 
     In an embodiment, the piston portion has a first outer diameter, and the rod portion further has a second outer diameter. The ratio of the second outer diameter to the first outer diameter is greater than 0.5. 
     The present invention will become clearer in light of the following detailed description of illustrative embodiments of this invention described in connection with the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIGS. 1 and 2  are cross-section views of an easy-to-assemble air pump of a embodiment according to the present invention. 
         FIG. 3  is another cross-section view taken along the line  3 - 3  of  FIG. 2 . 
         FIG. 4  is a cross-section view of a prior art portable air pump. 
     
    
    
     DETAILED DESCRIPTION 
       FIGS. 1-3  show an easy-to-assemble air pump of a embodiment according to the present invention. The easy-to-assemble air pump includes a cylinder  10 , a piston member  20 , a valve seat  30 , a valve connector  40 , a first pin member  50 , a handle  60 , and a second pin member  70 . 
     The cylinder  10  has a first through-hole  11  penetrating a periphery of the cylinder  10 , and an end cap  12  threadedly mounted at one end of the cylinder  10  opposite to the valve seat  30 . 
     The piston member  20  includes a piston portion  21  and a rod portion  22  integrally formed as a monolithic member. The piston portion  21  is axially movably arranged into the cylinder  10 . The rod portion  22  is movably coupled to the cylinder  10  for movement with respect thereto and extends out of the cylinder  10 . The rod portion  22  has a pivotal end  221  extending out of the end cap  12  and a first pivotal hole  222  provided at the pivotal end  221 . Further, the rod portion  22  is hollow and has a thickness T 22  greater than 0.6 mm. 
     Furthermore, the piston portion  21  has a first outer diameter D 21 , and the rod portion  22  further has a second outer diameter D 22 . The ratio of the second outer diameter D 22  to the first outer diameter D 21  is greater than 0.5. 
     The valve seat  30  is arranged in the cylinder  10  and has a second through-hole  31  aligning to the first through-hole  11 . The valve connector  40  is connected to one end of the cylinder  10  and has a third through-hole  41  aligning to the second through-hole  31 . The first pin member  50  inserts through the first through-hole  11 , the second through-hole  31 , and the third through-hole  41 . The first pin member  50  has a communicating bore  51  interconnected with the cylinder  10  and the valve connector  40 , so that the air compressed by the piston portion  21  in the cylinder  10  can pass through the valve seat  30  and the valve connector  40  to enter an inflatable object connected to the valve connector  40 . 
     The handle  60  has a second pivotal hole  61  aligning to the first pivotal hole  222 . The second pin member  70  inserts through the first pivotal hole  222  and the second pivotal hole  61 , thereby pivotally connecting the handle  60  to the pivotal end  221 . Further, both of the rod portion  22  and the handle  60  are made of plastic material to cause the handle  60  able to be directly pivotally connected to the rod portion  22  without any dissimilar material adaptor. 
     In summary, the easy-to-assemble air pump of this embodiment has the piston portion  21  and the rod portion  22  integrally formed as a monolithic member, so that the assembly step of the piston member  20  can be simply omitted during the process of assembling the air pump. There is no need to screw the piston and the pipe body like a conventional pump, which simplifies the assembly process of the air pump. In addition, when assembling the air pump of this embodiment, it is only necessary to install the valve seat  30  and the valve connector  40  on one end of the cylinder  10  respectively, and use the first pin member  50  to insert through the first through-hole  11  of the cylinder  10 , the second through-hole  31  of the valve seat  30 , and the third through-hole  41  of the valve connector  40  to finish the assembly process quickly, which greatly shortens the assembly time and reduces the production cost. 
     Although specific embodiments have been illustrated and described, numerous modifications and variations are still possible without departing from the scope of the invention. The scope of the invention is limited by the accompanying claims.