1. Field of the Invention
The present invention relates generally to a pump, and in particular to a bicycle tire pump which is manufactured at low cost and easily assembled.
2. The Prior Arts
A conventional bicycle tire pump is disclosed in
A piston rod 10 extends through the through hole 513 of the top cap 51 and is inserted into the cylinder 30. A piston head 11 is connected to the distal end of the piston rod 10 and includes a groove with which an O-ring is engaged. The piston head 11 can moved reciprocally in the cylinder 30 and this is known to the persons in the art and will not be described in detail. The other end of the piston rod 10 extends through the top cap 51 and is connected to a handle 12 for the user to operate the piston rod 10.
A base 20 and the second unit 60 are connected to the bottom end of the cylinder 30 and the base 20 is a flat board for supporting the pump on the ground. A tubular member 21 extends upward from the top of the base 20 and a hose 23 is connected to an outlet on the outside of the tubular member 21. A protrusion 22 extends from a top of the tubular member 21 and is inserted into the open bottom of the cylinder 30. Two side holes 221 are defined through the protrusion 22. A passage 222 is defined in the center of the tubular member 21 and communicates with the outlet and the hose 23. A groove 223 is defined in the protrusion 22 and receives a seal 24 therein. When the protrusion 22 is inserted into the cylinder 30, the seal 24 is in contact with the inner periphery of the cylinder 30 so form an air tight circumstance. The second unit 60 includes a sleeve 61 and two through holes 611 are defined through the sleeve 61. The sleeve 61 is mounted to the bottom end of the cylinder 30 and the tubular member 21 by bolts 73 extending through the through holes 611 of the sleeve 61 and connected to the washers 71 and the connection nuts 72 in the side holes 221.
This conventional bicycle tire pump includes a simplified design and includes the cylinder 30, the first unit 50, the second unit 60 and the base 20 so that it can be easily assembled. The cylinder 30 is a circular and cylindrical tube which can be easily machined and cut. When compared with other conventional tire pumps which have to be made with inner threaded holes in two ends of the cylinder, this conventional bicycle tire pump have benefits on the issues of assembly and fabrication. Nevertheless, there are some shortcomings to be improved which are:
A primary objective of the present invention is to provide a bicycle tire pump which can be manufactured at lower cost and includes less parts and material. The pump can be conveniently assembled. It is noted that the first unit and the piston rod are difficult to be improved, so that both of which will be used in the bicycle tire pump of the present invention. The characteristic in that the tubular member of the conventional pump is replaced by the connection member and the sleeve is replaced by the tubular member. The connection member includes an insertion rod and the tubular member on the base includes a connection hole and two positioning slots to make the assembling process to be more simplified and to reduce the cost of the fabrication.
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:
With reference to the drawings and in particular to
The base 40 includes a tubular member 41 so as to receive the bottom end of the cylinder 30. The tubular member 41 on the base 40 is higher than positions of the locking members 73 on the tubular member 41 and the cylinder 30. The tubular member 41 includes two positioning slots 411 defined in an inner periphery thereof so that the bolts 73 on the connection member 31 are accommodated within the positioning slots 411. The positioning slots 411 of the tubular member 41 accommodate the locking members 73 after the locking members 73 are connected to the cylinder 30 so as to restrict rotation of the cylinder 30 relative to the tubular member 41. By the positioning slots 411, the assembly of the cylinder 30 and the tubular member 41 can be easy and quickly. A connection hole 401 is defined through the base 40 and communicates with the tubular member 41. The insertion rod 313 extends through the connection hole 401 and is fixed with a fixing nut 74 so as to fix the cylinder 30 to the base 40. By the connection of the insertion rod 313 and the base 40 and the support of the tubular member 41, the cylinder 30 and the base 40 are firmly connected. The base 40 includes a communication path 402 which communicates with the connection hole 401 and is connected with a hose 42. In this embodiment, the communication path 402 communicates with another communication path 403 which is connected with a pressure gauge 80. A seal bolt 75 is connected to an opening defined by the communication path 402 to seal the communication path.
The pump of the present invention includes the following advantages:
Although the present invention has been described with reference to the preferred embodiment 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.