Patent Publication Number: US-2020300239-A1

Title: Hand air pump inflating device

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority of Taiwanese Patent Application No. 108109597, filed on Mar. 20, 2019. 
     FIELD 
     The disclosure relates to an air pump inflating device, and more particularly to a hand air pump inflating device. 
     BACKGROUND 
     A conventional hand air pump inflator for a racing bicycle, such as that disclosed in CN 101737294, generally includes an inner tube which is fixed to a nozzle at a front end, and an outer tube which is sleeved around the inner tube and displaceable relative to the inner tube for pumping air to the nozzle. A user grips and holds the inner tube with one hand, and pulls and pushes the outer tube with the other hand relative to the inner tube. The movement of the outer tube is interfered by the hand gripping the inner tube, which results in inconvenience during operation, and which limits a forward stroke of the outer tube and an inflating efficiency of the inflator. 
     SUMMARY 
     Therefore, an object of the disclosure is to provide a hand air pump inflating device that can alleviate at least one of the drawbacks of the prior art. 
     According to the disclosure, the hand air pump inflating device includes a nozzle and a cylinder mechanism. The nozzle has an inflating conduit formed therein. The cylinder mechanism includes a cylinder body, a tubular shaft, a tubular piston rod, a larger end cap, a smaller end cap, a front piston ring module, a rear piston ring module and a one-way check valve. The cylinder body extends in a longitudinal direction to terminate at opened front and rear cylinder ends. The front cylinder end is fixed to the nozzle. The tubular shaft is disposed within the cylinder body and extends in the longitudinal direction to terminate at opened front and rear shaft ends. The front shaft end is fixed to the nozzle and in air communication with the inflating conduit. The tubular piston rod is movably disposed within the cylinder body, surrounds the tubular shaft, and extends in the longitudinal direction to terminate at opened front and rear piston ends, such that the tubular piston rod is movable relative to the cylinder body and the tubular shaft in the longitudinal direction to reciprocate a rearward stroke and a forward stroke. The larger end cap is disposed on and encloses the rear piston end. The smaller end cap is disposed on and encloses the rear cylinder end and is sleeved on and in air-tight and movable engagement with the tubular piston rod. The front piston ring module is disposed on and encloses the front piston end, and has an outer ring portion which is in frictional engagement with the cylinder body to divide a space between the cylinder body and the piston rod into first and second chambers respectively close to the front and rear cylinder ends, and an inner ring portion which is sleeved on and in air-tight and movable engagement with the tubular shaft, such that the front piston ring module is moved with the tubular piston rod to interrupt air communication between the first and second chambers by the rearward stroke, and to permit the air communication between the first and second chambers by the forward stroke. The rear piston ring module is disposed on and encloses the rear shaft end, and is in movable and frictional engagement with the tubular piston rod to divide a space between the tubular piston rod and the tubular shaft into third and fourth chambers respectively close to the front and rear piston ends, such that the rear piston ring module is moved relative to the tubular piston rod to permit air communication between the third and fourth chambers by the rearward stroke, and to interrupt the air communication between the third and fourth chambers by the forward stroke. The check valve is disposed between the rear shaft end of the tubular shaft and the rear piston ring module to only permit passage of air from the fourth chamber to the tubular shaft. During the rearward stroke, a negative pressure is generated in the first chamber as a result of volume increment to introduce air thereinto, and air in the second chamber is pressed into the third chamber and the fourth chamber. 
     During the forward stroke, air in the first chamber is pressed to flow into the second chamber and the third chamber, a positive pressure is generated in the fourth chamber as a result of volume decrement to open the check valve, and air in the fourth chamber is pressed to flow into the tubular shaft. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other features and advantages of the disclosure will become apparent in the following detailed description of the embodiment with reference to the accompanying drawings, of which: 
         FIG. 1  is a perspective view illustrating an embodiment of a hand air pump inflating device according to the disclosure; 
         FIG. 2  is an exploded perspective view of the embodiment; 
         FIG. 3  is a sectional view of the embodiment; 
         FIG. 4  is a sectional view illustrating a state when a tubular piston rod of the embodiment is pulled by a rearward stroke; 
         FIG. 5  is a fragmentary, enlarged sectional view of  FIG. 4 ; 
         FIG. 6  is a sectional view illustrating a state when the tubular piston rod is pushed by a forward stroke; and 
         FIG. 7  is a fragmentary, enlarged sectional view of  FIG. 6 . 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIGS. 1 and 2 , an embodiment of a hand air pump inflating device  200  according to the disclosure is adapted to be coupled with an inflatable object (not shown), such as a bicycle tire, a ball, etc., and includes a nozzle  3  for the inflatable object to be coupled therewith, and a cylinder mechanism  4  securely mounted to the nozzle  3 . 
     Referring to  FIG. 3 , the nozzle  3  has an object coupling portion  31  which is coupled with the inflatable object and which has an inflating port  310 , and a cylinder coupling portion  32  which is connected with the cylinder mechanism  4 . The cylinder coupling portion  32  has an inflating conduit  320  formed therethrough and extending in a longitudinal direction to be in air communication with the inflating port  310 , and an intake slot  321  formed in an outer surrounding surface thereof and extending in the longitudinal direction. 
     Referring to  FIGS. 2 to 4 , the cylinder mechanism  4  includes a cylinder body  41 , a tubular shaft  43  and a tubular piston rod  42  each extending in the longitudinal direction to terminate at front and rear cylinder, shaft, or piston ends. The front cylinder end of the cylinder body  41  is fixed to the cylinder coupling portion  32  of the nozzle  3  to cooperatively define the intake slot  321  in air communication with the cylinder body  41  and ambient air. The tubular shaft  43  is disposed within the cylinder body  41  to have the front shaft end fixed to the cylinder coupling portion  32  of the nozzle  3  and in air communication with the inflating conduit  320 . The tubular piston rod  42  is movably disposed within the cylinder body  41 , and surrounds the tubular shaft  43  such that the tubular piston rod  42  is movable relative to the cylinder body  41  and the tubular shaft  43  in the longitudinal direction to reciprocate a rearward stroke and a forward stroke. 
     The cylinder mechanism  4  further includes a larger end cap  44  which is securely disposed on and encloses the rear piston end of the tubular piston rod  42 , a tubular handgrip  45  which is securely connected with the larger end cap  44  and has a grip wall extending forwardly to surround the rear cylinder end of the cylinder body  41 , a smaller end cap  46  which is securely disposed on and encloses the rear cylinder end of the cylinder body  41  and is sleeved on and in air-tight and movable engagement with the tubular piston rod  42 , a front piston ring module  47  which is securely disposed on and encloses the front piston end of the tubular piston rod  42  and is interposed between the cylinder body  41  and the tubular shaft  43 , a rear piston ring module  48  which is securely disposed on and encloses the rear shaft end of the tubular shaft  43  and is frictionally disposed within the tubular piston rod  42 , and a one-way check valve  49  which is disposed between the rear shaft end of the tubular shaft  43  and the rear piston ring module  48 . 
     Since the structures of the larger end cap  44  and the smaller end cap  46  may be varied and of a hitherto known type, a description thereof is dispensed with herein for the sake of brevity. 
     Specifically, the front piston ring module  47  has an outer ring portion which is in frictional engagement with the cylinder body  41  to divide a space between the cylinder body  41  and the piston rod  42  into first and second chambers  401 ,  402  respectively close to the front and rear cylinder ends of the cylinder body  41 , and an inner ring portion which is sleeved on and in air-tight and movable engagement with the tubular shaft  43 . The first chamber  401  is in air communication with the intake slot  321  for introducing air thereinto. In this embodiment, the front piston ring module  47  includes a front piston ring body  471  which is securely connected with the front piston end of the tubular piston rod  42 , and which has an outer annular groove  472  formed in an outer surrounding surface thereof, and a plurality of notched passages  473  extending in the longitudinal direction to be in air communication with the outer annular groove  472  and the second chamber  402 , a fixed seal ring  474  which is securely disposed on an inner surrounding surface of the front piston ring body  471  to serve as the inner ring portion, and a movable seal ring  475  which is received in the outer annular groove  472  to serve as the outer ring portion. 
     Referring to  FIGS. 3 to 5 , during the rearward stroke of the tubular piston rod  42 , the front piston ring module is moved rearward with the tubular piston rod  42  relative to the cylinder body  41  such that the movable seal ring  475  is slightly displaced forwards relative to the front piston ring body  471  due to frictional contact with an inner surrounding surface of the cylinder body  41  so as to seal the clearance between the front piston ring body  471  and the cylinder body  41  to interrupt the air communication between the first and second chambers  401 ,  402 . 
     Referring to  FIGS. 6 and 7 , on the contrary, during the forward stroke of the tubular piston rod  42 , the front piston ring module  47  is moved forward with the tubular piston rod  42  relative to the cylinder body  41  such that the movable seal ring  475  is slightly displaced rearwards relative to the front piston ring body  471  due to frictional contact with the inner surrounding surface of the cylinder body  41  so as to permit air communication of the outer annular groove  472  with the first chamber  401 , and with the second chamber  402  through the notched passages  473  to make the air communication between the first chamber  401  and the second chamber  402 . 
     Referring to  FIGS. 2 to 5 , the rear piston ring module  48  is in movable and frictional engagement with an inner surrounding surface of the tubular piston rod  42  to divide a space between the tubular piston rod  42  and the tubular shaft  43  into third and fourth chambers  403 ,  404  respectively close to the front and rear piston ends. Also, the tubular piston rod  42  has an aperture  420  which is formed at the front piston end and extends radially to be in air communication with the second chamber  402  and the third chamber  403 . The rear piston ring module  48  includes a rear piston ring body  481  which is securely connected with the rear shaft end of the tubular shaft  43 , and which has an axial hole  482  in air communication with the fourth chamber  404  and the tubular shaft  43 , an outer annular groove  483  formed in an outer surrounding surface thereof, and two diametrically opposite notched passages  484  extending in the longitudinal direction to be in air communication with the outer annular groove  483  and the fourth chamber  404 . The rear piston ring module  48  further includes a movable seal ring  485  which is received in the outer annular groove  483  and in air-tight abutment against the inner surrounding surface of the tubular piston rod  42 . 
     Referring to  FIGS. 4 and 5 , during the rearward stroke of the tubular piston rod  42 , i.e., when the rear piston ring module  48  is moved forward relative to the tubular piston rod  42 , the movable seal ring  485  is slightly displaced rearwards relative to the rear piston ring body  481  due to frictional contact with the inner surrounding surface of the tubular piston rod  42  to permit air communication of the outer annular groove  483  with the third chamber  403 . The outer annular groove  483  is in air communication with the fourth chamber  404  through the notched passages  484  (see  FIG. 2 ) so that the third chamber  403  is in air communication with the fourth chamber  404 . 
     Referring to  FIGS. 6 and 7 , on the contrary, during the forward stroke of the tubular piston rod  42 , i.e., when the rear piston ring module  48  is moved rearward relative to the tubular piston rod  42 , the movable seal ring  485  is slightly displaced forwards relative to the rear piston ring body  481  due to frictional contact with the inner surrounding surface of the tubular piston rod  42  so as to seal the clearance between the rear piston ring body  481  and the inner surrounding surface of the tubular piston rod  42  to interrupt the air communication between the third and fourth chambers  403 ,  404 . 
     Referring to  FIGS. 2, 5 and 7 , the check valve  49  includes a valve seat  490  which is formed in an end of the axial hole  482  of the rear piston ring body  481 , a valve disc  492  which is movably disposed between the valve seat  490  and the rear shaft end of the tubular shaft  43  in the longitudinal direction, and an annular valve housing  491  which is securely connected with the rear shaft end of the tubular shaft  43  and at a side of the valve disc  492  opposite to the valve seat  490  for receiving the valve disc  492  and limiting a forward movement of the valve disc  492 . The valve disc  492  is pressed to abut against and close the valve seat  490  by a pressure in the tubular shaft  43  which is larger than that in the fourth chamber  404  (see  FIG. 5 ), and to be away from the valve seat  490  by a pressure in the fourth chamber  404  which is larger than that in the tubular shaft  43  so as to permit passage of air from the fourth chamber  404  to the tubular shaft  43  (see  FIG. 7 ). 
     During the manual operation of the inflating device  200 , the nozzle  3  is coupled to an inflatable object. The user grips the front cylinder end of the cylinder body  41  with one hand, and the tubular handgrip  45  with the other hand to pull and push the tubular handgrip  45  and the tubular piston rod  42  relative to the cylinder body  41  so as to make rearward and forward strokes. 
     With reference to  FIGS. 3 to 5 , during the rearward stroke of the tubular piston rod  42 , i.e., when the cylinder mechanism  4  is stretched, a negative pressure is generated in the first chamber  401  as a result of volume increment to introduce air thereinto from the intake slot  321  (see  FIG. 2 ), as indicated by the arrow  801  of  FIGS. 4 and 5 , and air in the second chamber  402  is pressed, as a result of volume decrement, into the third chamber  403  and the fourth chamber  404 , as indicated by the arrow  801  of  FIGS. 4 and 5 . The rearward stroke is limited when the front piston ring module  47  abuts against the smaller end cap  46 . 
     Subsequently, the tubular handgrip  45  is pushed forward relative to the cylinder body  41  to retract the tubular piston rod  42  forward into the cylinder body  41 , i.e., the cylinder mechanism  4  is retracted until the larger end cap  44  abuts against the smaller end cap  46 , as shown in  FIG. 3 . 
     With reference to  FIGS. 6 and 7 , during the forward stroke of the tubular piston rod  42 , the front piston ring module  47  is moved to permit air communication between the first and second chambers  401 ,  402 . Air in the first chamber  401  is pressed, as a result of volume decrement in the first chamber  401 , to flow into the second chamber  402  and then into the third chamber  403 , as indicated by the arrow  802  of  FIGS. 6 and 7 . On the other hand, the rear piston ring module  48  is moved to interrupt the air communication between the third and fourth chambers  403 ,  404 . A positive pressure is generated in the fourth chamber  404  as a result of volume decrement to open the check valve  49  and air in the fourth chamber  404  is pressed to flow into the tubular shaft  43  through the axial hole  482 , as indicated by the arrow  802  of  FIGS. 6 and 7 . The air in the tubular shaft  43  further moves into the inflatable object through the nozzle  3 . 
     In this embodiment, the first chamber  401  in the cylinder body  41  is in air communication with the ambient air through the intake slot  321  formed in the outer surrounding surface of the cylinder coupling portion  32  of the nozzle  3  and defined by the fitting coupling of the cylinder coupling portion  32  with the front cylinder end of the cylinder body  41 . Alternatively, the intake slot  321  may be recessed in the inner surrounding surface of the cylinder body  41 . The intake slot  321  may be in the form of a penetrating hole formed through the cylinder body  41  to be in air communication with the first chamber  401 . Moreover, the check valve  49  may be alternatively in other various forms. 
     Furthermore, the tubular handgrip  45  of this embodiment may be dispensed therewith. In such case, the tubular piston rod  42  may be formed to further project rearwardly to form as a handgrip portion. Hence, the manual operation of the tubular piston rod  42  is convenient to conduct without interfering by the hand gripping the nozzle  3  or the cylinder body  41 . 
     As illustrated, with the cylinder body  41  secured to the nozzle  3  and the tubular shaft  43  disposed within the tubular piston rod  42  and secured to the nozzle  3 , the tubular piston rod  42  is movable relative to the cylinder body  41  and the tubular shaft  43  to reciprocate rearward and forward strokes, and the hands of the user can individually grip the nozzle  3  or the cylinder body  41 , and the rear piston end of the tubular piston rod  42  without interfering each other. Further, the tubular piston rod can be moved forward sufficiently to improve the inflating efficiency. The tubular handgrip  45  is disposed to render the manual operation more convenient. 
     Moreover, with the front and rear piston ring modules  47 ,  48  in the form of a one-way piston, during the rearward stroke of the tubular piston rod  42 , air in the second and third chambers  402 ,  403  is pre-pressed into and stored in the fourth chamber  404 , and during the forward stroke of the tubular piston rod  42 , the air in the fourth chamber  404  is pressed into the tubular shaft  43  while air in the first chamber  401  is pre-pressed into the second and third chambers  402 ,  403 . In this manner, the inflating efficiency of the inflating device  200  is further improved. 
     While the disclosure has been described in connection with what is considered the exemplary embodiment, it is understood that this disclosure is not limited to the disclosed embodiment but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.