Abstract:
A hand pump includes an automatic inflation device and a manual inflation device. The automatic inflation device includes a gas container containing pressurized gas for providing automatic and rapid inflation. When the automatic inflation device malfunctions or the gas container runs out of gas, the manual inflation device can be manually operated for inflation.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a hand pump with an automatic inflation valve and a manual inflation valve such that the user may choose the optional one for inflation. 
     2. Description of the Related Art 
     A typical automatic inflation device includes a gas container containing high-pressure gas (usually carbon dioxide) therein to allow rapid inflation. The gas container can be used only once. Namely, the user must replace a new one when the original container is used (opened), yet the user often forgets to do so. The present invention is intended to provide a hand pump with both automatic and manual inflation functions that mitigates and/or obviates the above problems. 
     SUMMARY OF THE INVENTION 
     It is a primary object of the present invention to provide a hand pump with an automatic inflation valve and a manual inflation valve to provide convenient optional choice to the user. The manual inflation device allows the hand pump to perform manual inflation operation when the automatic inflation malfunctions or the user forgot to replace a new gas container after previous use. 
     A hand pump in accordance with the present invention comprises: 
     a head including a compartment, a first passage communicated with the compartnent, and a second passage; 
     a cylinder including an inner chamber for receiving a gas container therein; 
     a first inflation valve mounted to the first passage; 
     a second inflation valve mounted to the second passage; 
     means for opening the gas container in the inner chamber; 
     means for guiding gas from the gas container to the first passage; and 
     a handle mounted around the cylinder to define an outer chamber between the handle and the cylinder, the handle being manually operable to slide relative to the cylinder, thereby forcing ambient air into the second passage via the outer chamber for inflation. 
     The inner chamber is communicated with the second passage and the outer chamber is communicated with the inner chamber via an air passage. The air passage includes a check-valve mounted therein such that air is only flowable from the outer chamber into the inner chamber. The cylinder includes a one-way valve means mounted in an outer periphery thereof such that air is only flowable from ambience into the outer chamber when the handle is moved away from the cylinder and that air is not flowable from ambience into the outer chamber when the handle is moved toward the cylinder. The cylinder includes an outer stop on the outer periphery thereof and the handle includes an inner stop on an inner periphery thereof to prevent disengagement of the handle from the cylinder. 
     The means for opening the gas container includes a needle securely mounted in the compartment and having a longitudinal hole. A plug is mounted around a portion of the needle and compressible to expose to the needle. The cylinder is movable toward to the head such that the gas container is moved to compress the plug and thus opened by the needle for supplying gas contained in the gas container. The cylinder and the head may be in threading connection to allow relative sliding movement therebetween upon rotation of one of the cylinder and the head. 
     A flow control valve is mounted in the head for controlling flow rate of gas from the gas container to the first passage. In a preferred embodiment of the invention, the flow control valve includes: 
     a control member in threading connection with the compartment of the head, the control member including a first end in the compartment of the head and a second end beyond the head for manual operation; 
     a valve stem slidably mounted in the compartment of the head, the valve stem including a first side and a second side; 
     an O-ring attached to the first side of the valve stem; 
     an elastic member having a first end attached to the second side of the valve stem and a second end attached to the needle, the elastic member biasing the O-ring toward the shoulder of the compartment for blocking the compartment; 
     whereby the control member is moved longitudinally relative to the valve stem upon rotation of the control member, the valve stem is movable by the control member away from the shoulder to open the compartment, thereby controlling flow rate of gas from the gas container to the first passage. 
     Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a sectional view of a hand pump in accordance with the present invention. 
     FIG. 2 is a sectional view similar to FIG. 1, wherein the gas container outputs gas in a lower flow rate. 
     FIG. 3 is a sectional view similar to FIG. 2, wherein the gas container outputs gas in a higher flow rate. 
     FIG. 4 is a sectional view similar to FIG. 1, wherein a handle of the hand pump is in its intake stroke. 
     FIG. 5 is a sectional view similar to FIG. 4, wherein the handle is in an outtake stroke. 
     FIG. 6 is a view similar to FIG. 1, illustrating a modified embodiment of the hand pump in accordance with the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to FIG. 1, a hand pump in accordance with the present invention generally includes a head  10  having a compartment  11 , the compartment  11  having a shoulder  111 . The head  10  further includes a first passage  12  to which a first inflation valve  13  is mounted and a second passage  14  to which a second inflation valve  15  is mounted. Inlet of the first passage  12  is communicated with the compartment  11 . The first inflation valve  13  is mounted to an outlet (not labeled) of the first passage  12  and includes a nozzle  131  for engaging with an object to be inflated, e.g., a tire valve of a bicycle. The second inflation valve  15  is mounted to an outlet (not labeled) of the second passage  14  and includes a nozzle  151 , a nozzle plug  152 , and an outer cap  153 . Nevertheless, it is noted that other inflation valves can be used to replace the first and second inflation valves  13  and  15 . 
     A needle  25  is securely mounted in the compartment and includes a longitudinal hole  251 . A plug  26  is mounted around an end (or a portion) of the needle  25  and is made of compressible material such that the plug  26  may be compressed along a longitudinal direction to expose the needle  25  for opening a gas container  33 . A low control valve  20  is mounted in the head  10 . In this embodiment, the flow control valve  20  includes a control member  21  that is in threading connection with the compartment  11  and that has a first end mounted in the compartment  11  and a second end beyond the head  10  for manual operation. An O-ring  211  is mounted around the first end of the control member  21  to prevent leakage of gas. The flow control valve  20  further includes a valve stem  23 , an O-ring  22  attached to a side of the valve stem  23 , and an elastic member  24  having a first end attached to the other side of the valve stem  23  and a second end attached to the needle  25 . Thus, the valve stem  23  may be actuated by the control member  21  to move toward/away from the first compartment  12  to thereby control flow rate of the gas from the gas container  22 , which will be described later. 
     A cylinder  30  includes an end with inner threading  31  for engaging with outer threading  16  of the head  10  such that the cylinder  30  may be moved toward or away from the head  10  upon rotation of the cylinder  30 . The cylinder  30  includes an inner chamber  32  for receiving the gas container  33 . The gas container  33  contains pressurized gas (usually carbon dioxide) for supplying air into the first inflation valve  13  via the needle  25 , which will be described later. 
     A substantially U-shape handle  40  is mounted around the cylinder  30 , thereby defining an outer chamber  41  between the handle  40  and the cylinder  30 . The handle  40  is slidable relative to the cylinder  30 . An air passage  38  is defined in the cylinder  30  and intercommunicates the inner chamber  32  with the outer chamber  41 . A check valve  34  (including a ball  342  and a spring  341 ) is mounted in the air passage  38  such that air is only flowable from the outer chamber  41  into the inner chamber  32  via the air passage  38 . The handle  40  includes an inner stop  42  (e.g., an inner flange) on an inner periphery thereof and the cylinder  30  includes an outer stop  35  (e.g., an outer flange) on an outer periphery thereof to prevent disengagement of the handle  40  from the cylinder  30 . Below the outer stop  35 , a one-way valve means  36  is mounted in the outer periphery of the cylinder  30 . In this embodiment, the one-way valve means  36  is an annular groove  361  with a notch  363  defined in an end thereof. An O-ring  362  is mounted in the annular groove  361 , which will be described later. 
     The gas container  33  in FIG. 1 is in a sealed condition and the valve stem  23  of the flow control valve  20  is biased by the elastic member  24  toward the control member  21  such that the O-ring  22  bears against the shoulder  111  of the compartment  11 , thereby blocking the compartment  11 . When automatic inflation is required, the user may rotate the cylinder  30  to make the cylinder  30  move toward the head  10  due to threading connection therebetween. As a result, the gas container  33  is moved to compress the plug  26  and thus in contact with the needle  25 , as shown in FIG.  2 . In addition, the control member  21  of the flow control valve  20  is rotated to move toward the valve stem  23  to thereby make the compartment  11  communicate with the first passage  12 . Thus, the gas container  33  is opened by the needle  25  and the gas (carbon dioxide) in the gas container  33  is supplied to the inflation valve  13  via the longitudinal hole  251  of the needle  25 , the compartment  11 , and the first passage  12 . It is noted that the gas container  33  in FIG. 2 outputs gas in a lower flow rate. When a higher flow rate is required, the user may further rotate the control member  21  to move the valve stem  23  more downward, best shown in FIG.  3 . 
     Referring to FIG. 4, when manual operation is required, e.g., the automatic inflation malfunctions or the gas container  33  runs out of gas, the gas container  33  is removed for manual inflation. As illustrated in FIG. 4, when the handle  40  is moved away from the cylinder  30 , ambient air enters the outer chamber  41  via the one-way valve  36 , as the O-ring  362  is moved to the notch  363  of the annular groove  361  and thus allows air to pass through the notch  363 . Referring to FIG. 5, when the handle  40  is moved toward the cylinder  30 , air in the outer chamber  41  enters the inner chamber  32  via the check valve  34  and then exits the hand pump via the second passage  14  and the second inflation valve  15 . Thus, manual inflation is allowed. It is noted that the gas container  33  may have a distance to an inner periphery defining the inner chamber  32  such that manual inflation still can be proceeded without removing the gas container  33 . In addition, the air passage  38  in the cylinder  38  may be arranged in a way other than the embodiment shown in FIGS. 1 through 5. 
     FIG. 6 illustrates a modified embodiment of the hand pump in accordance with the present invention, wherein the flow control valve  20  is arrange in a different orientation without affecting its function. 
     According to the above description, it is appreciated that the hand pump of the invention may automatically or manually inflate the valve of the object to be inflated. Thus, the hand pump can be used even if the user forgot to replace a new gas container after previous use. 
     Although the invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention as hereinafter claimed.