Pumps – Expansible chamber type – Plural pumping chambers
Reexamination Certificate
2000-04-06
2001-10-09
Walberg, Teresa (Department: 3742)
Pumps
Expansible chamber type
Plural pumping chambers
Reexamination Certificate
active
06299420
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an air pump, and more particularly, to a dual action air pump which can inflate and deflate at the same time and inflate an inflatable object during both up and down stroke to provide continuous discharge of compressed air.
2. Discussion of the Related Art
Children enjoy playing in inflatable toy structures, such as inflatable houses and above-the-ground pools. Conventional inflatable toy structures are inflated by using a manual or foot operated air pumps. The user of a manual air pump, such as a bicycle tire pump or inflatable toy pump, generally encounters difficulties in inflating a pneumatic article, such as a toy structure or tire. When commencing the pumping process, the article has a low (ambient) or no pressure and it is desirable to pump as large a volume of air as possible into the article with each pumping stroke. The user's difficulty at this stage is that many pumping strokes are required unless the volume of air per stroke is large. Conventional single action air pumps discharge the air inside through the air outlet only during the down stroke of the piston shaft. During the upstroke of the piston shaft, outside air is sucked into the air pump through an air inlet but no air is discharged through the air outlet.
Most manual or foot operated air pumps use the check valve concept to control the flow of air into their reservoirs and the subsequent discharging or exhausting of the air from the reservoir into the object being inflated. Check valves are necessarily provided in the air inlet and air outlet in order to control the air flow in a single direction. As an example, foot operated bellows pumps are normally spring loaded and operate with one intake and one exhaust check value. During the compression of the bellows air chamber (or reservoir) air exhausts into the object being inflated and during the spring-back, or up cycle, air refills the reservoir.
Additionally, it is a common manual air pump industry design to have this type of air pump inflate, but not deflate, an object on both the up and down strokes of the pumping cycle. These types of air pumps are commonly referred to as a double or dual action air pumps, and normally have their reservoir cylindrically shaped with intake check valves located at the opposite ends of the cylinder. As the pumping stroke drives the air out of either end of the cylinder, the opposite side check valve opens to allow the opposite side air to be replenished. During the pumping action where air on either side of a piston head is being compressed, the compressed air inflates the intended object by flowing through a side slit in a hollow piston shaft to which a hose is attached that is connected to the object to be inflated.
SUMMARY OF THE INVENTION
Accordingly, the present invention is directed to a dual action air pump that substantially obviates one or more of the problems due to limitations and disadvantages of the related art.
An object of the present invention is to provide an air pump that is used to inflate and deflate an inflatable object by changing a hose to appropriate air port opening.
Another object of the present invention is to provide an air pump that provides a continuous flow of air to an inflatable object during both up and down stroke of the piston shaft.
Another object of the present invention is to provide an air pump that provides a continuous flow of air from an inflatable object during both up and down stroke of the piston shaft.
Another object of the present invention is to provide an air pump that has both intake port and exhaust port that provide a continuous flow of air to and from the inflatable object during both up and down stroke of the piston.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, an air pump comprises a first structure having a hollow interior and a piston slidably disposed in the housing to divide the hollow interior of the housing to first and second reservoirs. In the preferred embodiment, as the piston moves toward a first direction, such as upstroke, the first reservoir is compressed and as the piston moves toward a second direction, such as down stroke, the second reservoir is compressed. The air pump further comprises a second structure having gaseous communication with the first structure. The second structure has intake and exhaust chambers which are not in gaseous communication with each other. The intake chamber is in gaseous communication with an intake port. The exhaust chamber is in gaseous communication with an exhaust port. The air pump also includes first and second intake check valves and first and second exhaust check valves disposed in the air pump. The first intake check valve provides gaseous communication between the second reservoir and the intake chamber when the piston moves in the first direction. The second intake check valve provides gaseous communication between the first reservoir and the intake chamber when the piston moves in the second direction. Similarly, the first exhaust check valve provides gaseous communication between the second reservoir and the exhaust chamber when the piston moves in the second direction, and the second exhaust check valve provides gaseous communication between the first reservoir and the exhaust chamber when the piston moves in the first direction.
According to one aspect of the present invention, the first and second intake check valves are located in the second structure and are dedicated to the intake chamber. The first and second exhaust check valves are also located in the second structure and are dedicated to the exhaust chamber.
In the preferred embodiment, the first structure is a cylindrical housing fixedly attached to the second structure, which is a base, wherein the first and second intake check valves are disposed in the second reservoir of the housing. The first and second intake check valves and the first and second exhaust check valves are preferably co-planarly located on the second structure.
According to another aspect of the present invention, the air pump includes an intake transfer tube connected between the intake chamber and the first chamber with air flow being regulated by the second intake check valve. There is also an exhaust transfer tube connected between the exhaust chamber and the first chamber with air flow being regulated by the second exhaust check valve.
According to another aspect of the invention, a piston shaft is fixedly connected to the piston for biasing the piston between the first and second positions. The piston shaft is parallelly disposed with the intake and the exhaust transfer tubes.
According to another aspect of the present invention, a disk is fixedly attached to one end of the housing. The disk defines an intake conduit connected to the intake transfer tube and further defines an exhaust conduit connected to the exhaust transfer tube. The disk further defines at least one air passage which is in gaseous communication with the first reservoir of the first structure.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide a further explanation of the invention as claimed.
REFERENCES:
patent: 4212595 (1980-07-01), Kuintzle, Jr. et al.
patent: 4392784 (1983-07-01), Hanafi
patent: 4990060 (1991-02-01), Cheng-Chung
patent: 5067882 (1991-11-01), DeVries et al.
patent: 5199857 (1993-04-01), Sanuki
patent: 5209190 (1993-05-01), Paul
patent: 5681154 (1997-10-01), Yang
patent: 5702239 (1997-12-01),
Hsu Yaw-Yuan
Lin Hua Hsiang
Saputo Richard A.
Intex Recreation Corp.
Lewis, D'Amato, Brisbois & Bisgaard LLP
Patel Vinod D.
Walberg Teresa
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