COMPACT HAND PUMP

Abstract

A watertight pump having a plunger used to causing air to be expelled from a nozzle of the pump. The plunger forms an interior compartment accessible by removal of a cap of the pump.

Description

BACKGROUND

The subject matter of this application relates to a compact hand pump for pumping air into an enclosure.

Hand pumps that pump air into enclosures (e.g. bicycles tires, air mattresses, floatation devices, etc.) are ubiquitous. Most such pumps are of sturdy construction, and frequently either weigh a great deal and/or are bulky, and often this size and bulk is undesirable, particular for outdoor recreational use. As one example, some hikers or other outdoor enthusiasts pack lightweight inflatable rafts, kayaks, or other watercraft as part of their backpacking gear and wish to, not only pack a great deal of gear in a relatively small enclosure, but also wish to minimize weight. Thus, there is always a need to minimize the weight and space occupied by the carried gear. Moreover, in such circumstances there are space and weight limitations on the inflatable watercraft as well. Thus there is always a need to reduce the weight and/or size of any air pump used to inflate, and carry within, lightweight inflatable watercraft.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which:

FIG. 1 shows an exemplary pump according to the present disclosure having an outer cylinder and an interior plunger.

FIG. 2 shows the pump of FIG. 1 with the plunger partially retracted from the cylinder.

FIG. 3 shows a top view of the pump of FIG. 1 with a cap of the plunger removed.

FIG. 4 shows a bottom view of the cap of the plunger of FIG. 1.

DETAILED DESCRIPTION

FIGS. 1 and 2 show an exemplary pump 10 that includes the systems and methods disclosed in this specification. The pump 10 has an outer enclosure or cylinder 12 into which a retractable plunger 16 fits. The outer end of the plunger 16 has a cap 18 forming an a bottom flanged surface so that the plunger may be easily and securely grasped. The plunger 16 has at its terminal end a flange (not shown) with an encircling gasket that fits tightly against the interior surface of the cylinder 12. In operation, as the plunger is alternately retracted from (as shown in FIG. 2) and then pushed into the cylinder, air is forced out of the pump through a nozzle 14 and into a device to be inflated.

The pump 10 is preferably fashioned of Polyvinyl Chloride (PVC) or a similarly lightweight material. This serves a number of purposes. First, as already noted, many outdoor enthusiasts who require air pumps desire to minimize the weight carried. Moreover, in the specific instance where the pump 10 is carried on an inflatable watercraft, the lightweight structure facilitates floatation of the pump in case it falls overboard for any reason.

Similarly, the pump 10 preferably comprises a compact form factor so that it may be easily inserted into, or strapped outside, a backpack or otherwise stowed on a watercraft with limited available space. To this end, the pump 10 preferably has a diameter of 3 inches or less and a length of 16 inches or less.

Even with the foregoing features, it is nonetheless desirable to design the pump 10 so that it more efficiently occupies the total amount of available space in a backpack or watercraft. This is a particularly acute need in the case of storage space on a watercraft in which stowed items often need to be secured in a selected one of one or more small compartments, built into the boat, e.g., a zippered pouch, a covered area at the head of an inflatable kayak, etc. Many such items are of critical importance, such as medicines, identifications, patch kits etc. that need to be reaily accessible. However, decreasing its form factor further in either diameter or length would make the pump 10 less efficient at pumping air into, e.g. a watercraft, and making the walls thinner to compensate for the diminished form factor would make the pump less rugged.

The present inventor realized, however, that the pump 10 could more efficiently utilize very limited space in a watercraft by alleviating the need for other carried items to take up more of that limited space. Referring to FIGS. 3 and 4, the cap 18 of the plunger 16 is preferably removable, and the plunger 16 is preferably hollow so that removal of the cap 18 provides access to a storage compartment 22 within the pump itself. The storage compartment 22 allows a person to store objects inside the pump 10, and therefore they do not occupy additional space in whatever limited storage capacity is available, i.e. the storage compartment 22 frees up more room to carry additional cargo.

In a preferred embodiment, the storage compartment 22 is at least 1 inch in diameter and extends at least a major portion of the length of the plunger. In another preferred embodiment, the compartment 22 is at least 1.25 inches in diameter and in yet another preferred embodiment the compartment 22 is at least 1.5 inches in diameter. Also, in any of these embodiments, the storage compartment may also preferably extend at least 80% of the length of the plunger, or at least 90% of the length of the plunger.

The cap 18 may preferably be locked into sealing engagement into the opening 22 of the plunger 16. This sealing engagement not only keeps the cap 18 locked to the plunger 16, but also preferably forms a watertight seal In the embodiment shown in FIGS. 3 and 4, the underside of the cap 18 preferably includes a circular protrusion 24 that is received into the opening 22 of the plunger 16. The opening 22 into the plunger 16 is preferably surrounded by a notched periphery 17 so that flanges 25 of the protrusion 25 may be matingly received in the notches of the opening 22 of the plunger 16. In this manner, by inserting the cap into the plunger and twisting, the cap locks into a watertight seal with the plunger.

The cap 18 also preferably includes a flexible gasket 18 so provide the watertight seal just mentioned. The periphery 17 of the opening 22 also preferably includes opposed ledge members 30 adjacent the notches of the plunger 16. The ledge members 30 preferably each have a variable thickness that increases from their edges to the center; in this manner as the cap 18 is twisted into the locked position, the cap pulls down into the opening 22, compressing the flexible gasket 18 to form a tight seal. Twisting the cap in the opposite direction expands the flexible gasket and allows removal of the cap18 from the plunger 16 and access into the compartment 22.

It will be appreciated that the invention is not restricted to the particular embodiment that has been described, and that variations may be made therein without departing from the scope of the invention as defined in the appended claims, as interpreted in accordance with principles of prevailing law, including the doctrine of equivalents or any other principle that enlarges the enforceable scope of a claim beyond its literal scope. Unless the context indicates otherwise, a reference in a claim to the number of instances of an element, be it a reference to one instance or more than one instance, requires at least the stated number of instances of the element but is not intended to exclude from the scope of the claim a structure or method having more instances of that element than stated. The word “comprise” or a derivative thereof, when used in a claim, is used in a nonexclusive sense that is not intended to exclude the presence of other elements or steps in a claimed structure or method.

Claims

1. A pump comprising: an outer enclosure operably engaged with an inner plunger, operation of the plunger causing air to be expelled from a nozzle of the pump;a handle selectively securable to and removable from an outer terminus of the handle; whereinthe plunger forms an interior compartment accessible when the lid of the plunger is removed.

2. The pump of claim 1 where the pump is watertight when the lid is engaged with the handle.

3. The pump of claim 1 where the handle and lid are capable of lockable engagement with each other.

4. The pump of claim 1 including a gasket that surrounds a protrusion of the lid.

5. The pump of claim 4 where rotation of the protrusion of the lid within the compartment compresses the gasket.

6. The pump of claim 1 that floats in water.

7. The pump of claim 1 made of PVC.