Abstract:
An air pump nozzle includes a housing with an inflation hole. An inner space of the housing lodges a block assembly seat having a compartment at an end. The compartment lodges a block member having an insertion hole. A needle tube with an air outlet is inserted through the insertion hole and is retained from affiliating from the block member. The design of separate needle tube and block assembly seat can simplify the manufacturing procedure and product assembly, as well as reduce the manufacturing cost.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to an air pump apparatus, and in particular to an air pump nozzle for engaging with an inflation valve of an inflatable object. 
         [0003]    2. The Prior Arts 
         [0004]    Inflation valves are universally found installed on inflatable objects, such as tires. When inflation is needed, the inflation valve is engaged with a nozzle fastened to an air hose to allow air to be pumped into the inflatable object. 
         [0005]    A conventional inflation valve is provided with a valve needle. When the valve needle is in a standby position, the air pressure inside the inflatable object seals the air valve and prevents the air from leaking out. When the valve needle experiences an external force, the valve is opened up, which enables the inside of the inflatable object to communicate with the atmospheric air and allows air to be discharged from or charged into the inflatable object. 
         [0006]    In general, there are two methods to inflate an inflatable object. One is to engage a nozzle fastened to a hose with the inflation valve of the inflatable object. The hose is in turn connected with an air pump or an air compressor, so that air is pumped through the hose and the nozzle into the inflatable object. The other method is to engage the nozzle directly disposed at an air outlet of the air pump with the inflation valve, so that air may be pumped through the nozzle into the inflatable object. 
         [0007]      FIGS. 6 and 7  illustrate the structure of a conventional air pump nozzle, which comprises a housing A, whose inner space holds an needle tube E, a sleeve body D, and a block member C, and a cap B which closes the inner space of the housing A. The needle tube E is received in the block member C, which as a whole is received in the sleeve body D. A first end E 1  of the needle tube E protrudes through the housing A to be connected with a hose. When the cap B is engaged with the air valve of the inflatable object, a second end E 2  of the needle tube E repels against a valve needle inside the air valve, and opens the air valve to allow air to be filled in from a central hole E 4 . 
         [0008]    The conventional needle tube E is structured with a tubular body having a protruded edge E 3  formed at a proper position in its outer periphery. The protruded edge E 3  divides the needle tube E into the first end E 1  and the second end E 2 . The first end E 1  is to be connected with a hose, while the second end E 2  is to be pressed against the air valve of an inflatable object. The housing A has to be capable of rotating freely around the needle tube E in order to engage the cap B connected to the housing A with the inflation valve. To fulfill the requirement, the metal sleeve body D is disposed covering the block member C and part of the needle tube E to avoid the friction between the rubber block member C and an inner periphery of the housing A from hindering the housing rotation. 
       SUMMARY OF THE INVENTION 
       [0009]    An objective of the present invention is to solve the structural problem of a conventional nozzle, wherein a sleeve body is required to isolate the inner periphery of the housing from the block member in order to avoid hindrance to the housing rotation caused by the contact therebetween. The requirement of the sleeve body complicates the manufacturing procedure and product assembly, which impedes the reduction of the manufacturing cost. 
         [0010]    A primary feature of the present invention is to provide a block assembly seat which lodges the block member and the needle tube. The combination of the separate block assembly seat and the needle tube supersedes the aforementioned conventional integrally molded needle tube, as well as provides the insolating function of a conventional sleeve body. 
         [0011]    One technical means of the present invention is to form a block assembly seat by mechanical machining or integral molding. At one end of the block assembly seat is a seat head with an enlarged diameter. The seat head is provided with a compartment for lodging the block member and the needle tube. A sidewall of the seat head isolates the block member from the inner periphery of the housing. The isolation prevents the housing rotation from being hindered by the friction caused by the contact between the rubber block member and the metal housing. In this respect, the block assembly seat supersedes the conventional sleeve body. 
         [0012]    A further technical means of the present invention is, after the block member and the needle tube are lodged in the compartment of the block assembly seat, to align an air outlet of the needle tube with an air inlet of the block assembly seat, so that the air flow will not be affected. In this respect, the block assembly seat supersedes the conventional sleeve body. 
         [0013]    An even further technical means of the present invention is, after the needle tube is installed in an insertion hole of the block member, to fit the protruded edge of the needle tube in a concave edge formed at the end of the insertion hole to prevent the needle tube from disaffiliating from the block member. 
         [0014]    A still further technical means of the present invention is that, after the needle tube is fitted into the block member and then as a whole lodged in the compartment of the block assembly seat, which is in turn lodged in an inner space of the housing, the inner space is closed with a cap to prevent the block assembly seat from disaffiliating from the housing. 
         [0015]    According to the present invention, the block member is isolated from the housing by the sidewall of the seat head of the block assembly seat. The isolation assures the smoothness of the housing rotation by avoiding the contact between the rubber block member and the metal housing. In this respect, the present invention supersedes the conventional sleeve body. Furthermore, the air flow from the block assembly seat to the needle tube is not affected. In this respect, the present invention supersedes the integrally molded structure of a conventional needle tube. Accordingly, the design of separate needle tube and block assembly seat according to the present invention not only simplifies the manufacturing procedure and product assembly, but also reduces the manufacturing cost. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]    The present invention will be apparent to those skilled in the art by reading the following detailed description of a preferred embodiment thereof, with reference to the attached drawings, in which: 
           [0017]      FIG. 1  is an exploded perspective view of an air pump nozzle in accordance with a preferred embodiment of the present invention; 
           [0018]      FIG. 2  is a cross-sectional view of  FIG. 1 ; 
           [0019]      FIG. 3  is a cross-sectional view of the assembled air pump nozzle in accordance with the preferred embodiment of the present invention; 
           [0020]      FIG. 4  is an exploded perspective view of a needle tube and a block assembly seat in accordance with another preferred embodiment of the present invention; 
           [0021]      FIG. 5  is a cross-sectional view of an assembly of the needle tube and the block assembly seat shown in  FIG. 4 ; 
           [0022]      FIG. 6  is a cross-sectional view of a conventional air pump nozzle; and 
           [0023]      FIG. 7  is an exploded cross-sectional view of the conventional air pump nozzle in  FIG. 6 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0024]    With reference to  FIGS. 1-3 , an air pump nozzle in accordance with a preferred embodiment of the present invention comprises a housing  1 , a cap  2 , a block assembly seat  3 , a needle tube  4 , and a block member  5 . Each of the aforementioned components includes a first end and a second end. The first ends are defined with the same orientation, while the second ends are defined with the orientation opposite to the first ends. 
         [0025]    The housing  1  is not limited to any material for manufacturing, but metal is preferred for strength and hardness considerations. The first end of the housing  1  is provided with an inflation hole. An inner periphery of the inflation hole is provided with a first inner thread  11  for engaging with an outer thread of the inflation valve of an inflatable object, as shown in  FIG. 3 . The housing  1  is provided at the second end thereof with an inner space  10 , which is in communication with the inflation hole. The diameter of the inner space is greater than that of the inflation hole. The inner space  10  is provided at the end of the inner periphery thereof with a second inner thread  12 . 
         [0026]    The cap  2  is provided at the first end with an outer thread  21  which is in pair with the second inner thread  12 , and a through hole  20  at a center thereof which extends from the first end through the second end. 
         [0027]    The block assembly seat  3  may be manufactured with any material with proper strength and hardness, such as plastic or metal. At the first end of the block assembly seat  3  is formed with a seat head  31  with a larger diameter than the second end. The seat head  31  is provided at the end thereof with a concave compartment of a proper depth. The outer diameter of the seat head  31  is slightly smaller than the inner diameter of the inner space  10  of the housing  1 , so that the seat head  31  may be lodged in the inner space  10 . On the other hand, the outer diameter of the second end of the block assembly seat  3  is slightly smaller than the inner diameter of the through hole  20  of the cap  2 , so that the second end may be inserted through the through hole  20 . 
         [0028]    The block member  5  is manufactured with material of excellent airtight performance, such as rubber. An insertion hole  51  is formed at a center of the block member  5 . A concave edge  52  with an enlarged diameter is formed at an inner periphery of the second end of the block member  5 . The outer diameter of the block member  5  is virtually equivalent to the inner diameter of the compartment  310  of the block assembly seat  3 . 
         [0029]    The needle tube  4  is provided with an air outlet  42  extending from the first end through the second end. The needle tube  4  is provided at the second end thereof with a protruded edge  41  corresponding to the concave edge  52  of the block member  5 . The outer diameter of the needle tube  4  is virtually equivalent to the inner diameter of the insertion hole  51  of the block member  5 . 
         [0030]      FIGS. 4 and 5  depict another embodiment of the needle tube  4  of the present invention, in which a protruded central rod  43  is formed at the first end, with a number of small air slots  44  positioned around a periphery thereof extending through the second end. A protruded edge  41  is formed at the periphery of the second end of the needle tube  4 . The outer diameter of the needle tube  4  is virtually equivalent to the inner diameter of the insertion hole  51  of the block member  5 , so that after the needle tube  4  is inserted through the insertion hole  51  of the block member  5 , the protruded edge  41  may rest against an end portion of the block member  5 . 
         [0031]    Please refer to  FIG. 1  and  FIG. 2  for the assembly of the present invention. Firstly, the needle tube  4  is inserted through the insertion hole  51  from the second end of the block member  5  and is retained in position by fitting the protruded edge  41  into the concave edge  52 . Then the block member  5  is lodged in the compartment  310  of the block assembly seat  3 . The seat head  31  of the block assembly seat  3  is in turn lodged in the inner space  10  of the housing  1 , while the second end of the block assembly seat  3  is inserted through the through hole  20  of the cap  2 . Lastly, the outer thread  21  of the cap  2  is engaged with the second inner thread  12  of the housing  1 , which completes the assembly thereof. 
         [0032]    With reference to  FIG. 3 , the sidewall of the seat head  31  of the block assembly seat  3  isolates the block member  5  from the inner periphery of the housing  1 . The seat head  31  is fitted loosely with the inner periphery of the housing  1 , so is the second end of the block assembly seat  3  fitted with the through hole  20  of the cap  2 . Accordingly, with the block assembly seat  3  remaining static, the housing  1  and the cap  2  are capable of rotating freely in correspondence to the block assembly seat  3 , which allows the first inner thread  11  of the housing  1  to be engaged with the outer thread of the inflation valve  6 . 
         [0033]    Although the present invention has been described with reference to the preferred embodiments thereof, it is apparent to those skilled in the art that a variety of modifications and changes may be made without departing from the scope of the present invention which is intended to be defined by the appended claims.