Patent Application
20080247884
1. Field of the Invention
The present invention relates to an air pump for inflating air-inflatable objects (such as a tire), and in particular, to an air pump having advantages such as occupying a smaller volume and is portable.
2. The Prior Arts
Generally, the conventional air pump mainly includes an inflating pump, a head for connecting with the inflating pump, and a dispensing head, in which one end is connected with the head. After the other end of the dispensing head is connected with an air valve of the inflated object, the inflating pump can be operated so as to produce compressed air, and then the air can be inflated into the inflated object through the head and an air hose.
For the sake of allowing for easier carrying portability, several air pumps have been designed to occupy a smaller volume, such as a conventional air pump as shown in
But the above conventional air pump has many disadvantages described as follows. During the inflating process, the air may be discharged due to leakage while operating the lever to engage and disengage the nosepiece D onto the air valve of the tire; and the nosepiece may be loosened from the inflating valve as the air pressure in the tubular body becomes too high. In addition, when the air pump is used, the user is required to hold the tubular body by one hand and to hold the handle by using the other hand, so that the entire length of the air pump can not be reduced, and because the dimensions of the air pump remains to be too big, therefore, it is inconvenient for carrying.
A main objective of the present invention is to resolve some of the problems of the conventional portable air pump, such as having disadvantages of excessive volume and inconvenient for carrying. In addition, the conventional portable air pump has the problem of easily discharging air leakage when engaging and disengaging the nosepiece onto the inflating valve when operating the lever. Furthermore, the nosepiece may be easily loosened as the air pressure in the tubular body becomes too high.
Another objective of the present invention is form a tubular body of an air pump to be used as a handle; a piston mechanism and a barrel are to be assembled inside the tubular body. Furthermore, the piston mechanism includes a piston, a check valve seat, and a check valve disc. The check valve seat and the check valve disc are used for preventing the gas or air from flowing in the reverse direction. When the air pump is not being used, the entire barrel can be retreated inside the tubular body, so that the overall volume of the air pump can be reduced to as small as possible, and it is more convenient for carrying or for storage.
The dispensing head is connected with the inflating valve of the inflated objects by means of a threaded connection. Therefore, as compared to the conventional air pump, the connecting means of the present invention is not only easier, but also tighter, so that the dispensing head is not easily loosened under higher gas pressure. Furthermore, the inflating valve used in the screw-on type connecting method occupies a smaller volume, and can be more easily operated.
The portable air pump of the present invention includes a tubular body, a barrel, a piston mechanism, a head, and a dispensing head. The first end of the tubular body is formed with a plurality of air inlet holes. In addition, the second end of the tubular body is sealed. The barrel has an air passage that runs through the first end to the second end of the barrel. Furthermore, the piston mechanism includes a piston, and a check valve. The piston is disposed at the second end of the barrel. The check valve is disposed in between the second end of the barrel and the piston, and making the piston and the second end of the barrel to be disposed inside the tubular body. The piston has a center hole and a through hole. The head is disposed at the first end of the barrel. The dispensing head is disposed at the head. As the tubular body is moved along the axis direction of the barrel and in the direction away from the head, air is flown into the tubular body through the air inlet holes of the upper cover, and then to the bottom of the tubular body through the through hole of the piston; and the check valve disc is used for preventing air to flow through the center hole. As the tubular body is moved in the direction towards the head in relation to the barrel, the air at the bottom end of the tubular body is to flow into the air passage of the barrel, and then flown out from the head and the dispensing head.
The check valve includes a check valve seat and a check valve disc. Furthermore, the check valve includes a check valve seat having a stepped tubular body, one end of which is inserted into the air passage of the second end of the barrel and the other end of which is inserted into the piston; and a check valve disc, which is positioned inside the check valve seat, and the check valve disc is able to move in between the center hole of the piston and the central hole of the check valve seat.
In order to avoid collision of the tubular body of the air pump for producing a noise or causing damage as the tubular body is moved in relation to the barrel along the axis direction, buffer rings can be used in the present invention, which can be disposed on the barrel at the inside or outside of the tubular body. More specifically, the buffer rings are adjacent to the head and the piston, respectively, so that as the tubular body moves in the forward (inflating) stoke to a limit position, the piston can be avoided from colliding with the upper cover on the tubular body directly; and as the tubular body moves in the back stoke, the head can be avoided from colliding with the upper cover.
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:
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings. The present invention will be apparent to those skilled in the art by reading the following detailed description of a preferred embodiment and the skilled can operate it according to the reference.
The barrel 2 has a hollow tubular body, whose external diameter is smaller than the internal diameter of the tubular body 1, and the first and second ends of the barrel 2 are formed with a first outer screw thread 23 and a second outer screw thread 24, respectively. Also, the hollow space inside the barrel 2 is of an air passage 21 that runs through the first end and the second end of the barrel 2.
Furthermore, the piston mechanism 3 includes a piston 31 and a check valve. The outer diameter of the piston 31 is formed with an annulus groove 310; and the center of the piston 31 is formed with a center hole 311. Furthermore, the upper end of the piston 31 is screwed on and engaged with the second outer screw thread 24 of the second end of the barrel 2. A plurality of through holes 312 running to the annulus groove 310 is formed on the bottom of the piston 31. Furthermore, a piston ring 32 is positioned to engage with the annulus groove 310.
In addition, the check valve includes a check valve seat 33 and a check valve disc 34. The check valve seat 33 has a stepped tubular body and a central hole 331. The check valve disc 34 has a soft body, and is disposed inside the larger inner diameter of the check valve seat 33; and thus the check valve disc 34 can move in between the center hole 311 of the piston 31 and the central hole 331 of the check valve seat 33. After the second end of the barrel 2 is fitted with a second buffer ring 35, the end of the check valve seat 33 which has the smaller outer diameter is positioned inside the inner diameter of the second end of the barrel 2. Then, after the check valve disc 34 is disposed inside the end of the check valve seat 33 having the larger outer diameter, the check valve seat 33 is positioned into the upper end of the piston 31; and then the upper end of the piston 31 is screwed on and engaged with the second outer screw thread 24 of the barrel 2.
Furthermore, the head 4 has a gas passage running through its bottom surface and side surface, on the two ends of which, a first screw hole 41 and a second screw hole 42 are formed, respectively. After the first end of the barrel 2 is fitted with a first buffer ring 22, the first outer screw thread 23 is engaged with the first screw hole 41 of the head 4, and thus the gas passage of the head 4 is communicated with the air passage 21 of the barrel 2.
In the embodiment, the dispensing head 5 is a screw-on swivel head, in which one end is engaged with the second screw hole 42 of the head 4, and the other end of the dispensing head 5 can be engaged with the inflating valve 6 of the inflated objects (with reference to
During the inflating stroke, the upper cover 11 may collide with the head 4 to produce a noise or damage the air pump. So in the embodiment of the present invention, the first buffer ring 22 is used as a buffering member between the head 4 and the upper cover 11 for avoiding the above problem. Also, in the back stroke, the upper cover 11 may also collide with the piston 31 to produce a noise or damage the air pump, so the second buffer ring 35 is used as the buffering member between the piston 31 and the upper cover 11 for avoiding the problem. Referring to
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.
