GB2325495A - Integral pump and its method of manufacture - Google Patents

Abstract

The pump 10 is integral to the inflatable article 20, for example a cushion to be inflated. The pump includes chambers 11<SP>I</SP>,11<SP>II</SP> each housing foam inserts 12. The outer chamber wall 11a has a non-return valve 13. Further non-return valves 14 are located in the adjoining walls 11a, 11b to the rest of the article. The pump is operated alternately by compressing and releasing the chambers so that upon expansion of the foam within air is drawn in through the non-return valve 13 and upon compression the air is forced out into the adjacent cells via non-return valves 14. The article can thus be readily inflated manually.

Description

PUMP The present invention relates to a pump for inflation of an inflatable article and in particular to a pump integrated within the body of the article to be inflated.

It is known to provide pumps with inflatable body support cushions, pads or mattresses. The pumps may be electrically or manually actuated. Currently, manually actuated pumps comprise a bellows or cycle pump device releasably connected to the article to be inflated, which pump/device upon inflation is disconnected and retained nearby for re-inflation of the article from time to time.

This is inconvenient if the pump/device is misplaced or stored in one location which then limits the use of the article. A further disadvantage is that the provision of the combined pump and article requires manufacture of two disparate types of equipment, thereby resulting in increased costs.

Accordingly, the invention seeks to provide improvements.

The present invention provides a pump for inflating an inflatable article, the pump comprising a flexible walled chamber, the chamber housing a resilient material and having at least one non-return inlet valve for flow of fluid into the chamber and at least one non-return outlet valve for flow of fluid from the chamber wherein the chamber is located within and is an integral part of the article to be inflated.

The pump is integrated with and forms part of the article to be inflated and preferably may be manufactured in a single operation with the aricle, thereby simplifying manufacture and reducing costs.

Moreover, the integrated pump can be used to inflate the article and re-used as necessary to re-inflate anywhere and at anytime without the necessity of carrying and retaining pump accessories as previously. Preferably, there are a plurality of inlet valves and more preferably a greater plurality of outlet valves with the pump chamber housing an open-celled compressible material for improved pumping action. The compressible material may be one or more foam annuli corresponding to the shape of the pump chamber and conveniently the inlet valve(s) may be located at or near the centre of the foam annuli for increased intake of air during compression of the pump.

Advantageously, the pump chamber retains an inflated position after pumping action, so that the external shape of the pump chamber and the article are contiguous, providing a continuous surface of the article.

In a preferred embodiment, the pump is adapted to inflate and forms part of a multi-layer body support cushion comprising a plurality of inter-connecting laterally adjacent cells adapted to be inflated with fluid and having vertically stacked inter-communicating upper and lower chambers, with at least one such cell forming the pump chamber(s).

Preferably, the inflatable multi-layer cushion with the pump is formed in a single sealing operation.

Each of the cells may be generally of hourglass shape defined by vertically stacked inflated upper and lower chambers and a centre neck portion. The upper and lower chambers of the cells are disposed in separate layers of the cushion and channels are provided for fluid communication between the upper chambers and adjacent cells and between the lower chambers and adjacent cells.

Apertures in some of the cells provide interlayer communication between the upper and lower chambers.

The invention will now be described in more detail by way of example, with reference to the accompanying drawings, in which: Figure 1 is a cross-sectional view of the preferred embodiment of a multi-layer inflatable cushion with an integrated pump of the present invention; Figure 2 is a top plan view of the cushion and pump of Fig. 1; Figure 3 is a cross-sectional view of a three layer cushion and pump of Fig. 1; Referring to Figure 1, pump 10 includes flexible walls Ila and lib defining chambers 11', 11". Foam pieces 12 and 12' are disposed respectively in chambers 11', 11". One of the walls lia has a non-return inlet valve 13 located centrally of the cell and a plurality of non-return outlet valves 14 located in-between the join of the walls lia and lib. The inlet and outlet valves are conventional high performance, low leakage devices and the use of multiple valves (e.g. 2 inlet, 4 outlet) provides rapid expelling of the pump chamber air into the adjacent cells, and also rapid recovery of the shape of the pump chamber. This combination allows for quick inflation of the inflatable multi-layer cushion without having to rely on high (e.g.

foot) external pressures to be used for inflation and therefore the cushion can be pumped by hand.

The pump operates by alternately compressing and releasing the chamber walls gila, lib manually so that upon expansion of the foam air will be drawn through the non-return inlet valves and upon compression of the pump chamber walls air is forced into the adjacent cells through the non-return outlet valves. Thereafter when the pump chamber walls are released air is again drawn into pump chamber through the inlet valves.

As shown in Fig. 1, the cushion 20 comprises at least two superimposed layers 21 and 23. Each layer is formed by two thermoplastic sheets 30 and 30', 32 and 32' selectively sealed, to define discrete, vertically stacked fluid-filled cells 11. E oh of the cells 11, as shown, may be of generally hourg-ass shape defined by vertically stacked, upper and lower chambers 11' and 11'' joined together at the adjacent and central points of their abutting walls and defining a neck portion 15 therebetween.

Channels 22 are defined by the unsealed portions of the sheets 30 and 30' and as such, are formed directly into the layer 21 to provide intralayer fluid communication between the adjacent upper chambers 11' of the cells 11.

Channels 22' provide intralayer fluid communication within layer 23 between the lower chambers 11'' of the adjacent cells 11. In order to provide for interlayer fluid communication directly between the upper chambers 11' of the cells 11 in layer 21 and between the lower chambers 11'', in layer 23, slits 50 are provided in the neck portions 15 of at least some of the cells 11.

The upper and lower layers 21 and 23, including, respectively, the chambers 11' and 11'' is each formed by selectively sealing together two sheets of heat-sealable thermoplastic material. Each cell 11 is preferably of rectangular configuration, but may be circular or polygonal. It may be seen that the channels 22 that interconnect adjacent cells 11, form a checkerboard, or grid pattern During manufacture, each pair of thermoplastic sheets 30 and 30' and 32 and 32' are superimposed face-to-face and sealed together by RF welds or similar to generally conform to the horizontal pattern of the cells, as shown in Fig. 2. The pump foam material 12 is sandwiched in between the sheets in the required positions. The inner surfaces of each of the outer sheets 30 and 32' are coated with release material which will prevent the sealing together of those portions of the sheets that conform to the location of the upper and lower chambers of the cells 11 and the channels 22 and 22'. The sheets also have the pump inlet 13 and outlet 14 valves located prior to the sealing together of the sheets. The inner surface of the intermediate sheet 32 is coated with release material which will prevent the sealing together of the neck portions where apertures 50 are to be formed. The apertures 50 are cut into the intermediate layers 30', 32 at predetermined locations prior to the sealing procedure.

The barrier coating or release material may be applied, by conventional printing techniques, such as silk screening, rotogravure of flexographic process. With the release material firmly bonded to the sheets 30, 30', 32 and 32', or the barrier coating of, for example, polyethylene, Teflon or silicone particles applied, the sealing of the coated areas in the abutted portions of the sheets is inhibited.

The outer seal 36 welds or fuses the outer sheet 30 and 32' to the intermediate sheets 30' and 32 to form upper and lower chambers 11' and 11'' of the cells 11 and the inner seal 37 seals the intermediate sheets 30' and 32 together to thereby connect the upper and lower chambers to form the cells' hourglass shape.

The embodiment in Figs. 3 shows a cushion 20 having three inflatable layers 21, 23 and 25 comprising a plurality of adjacent cells having three vertically stacked chambers with an integrated pump in each of the layers. The third or bottom chamber 11' '' may communicate with the other two chambers 11' and 11'' to increase the dampening of the cushion or may be isolated therefrom to permit the third layer to be independently inflated to provide a firm base cushion and reduce the likelihood of "bottoming out".

In these body support cushions comfort is an important feature and the uppermost, or outermost surfaces of the cells 11 provide initial contact with the person's body.

The integrated pump being configured to be part of the cushion and contigous therewith provides a smooth outer surface that ideally suits this requirement.

Claims (9)

1. Pump

   Claims: 1. A pump for inflating an inflatable article comprising a flexible walled chamber, the chamber housing a resilient material and having at least one non-return inlet valve for flow of fluid into the chamber and at least one nonreturn outlet valve for flow from the chamber wherein the chamber is located within and is an integral part of the article to be inflated.
2. 2. A pump according to claim 1, wherein the inlet valve is located centrally of the chamber.
3. 3. A pump according to claim 1, including a plurality of inlet valves and/or a plurality of outlet valves.
4. 4. A pump according to claim 3, wherein the chamber includes compressible material.
5. 5. A pump according to claim 4, wherein the compressible material comprises one or more foam annuli and the or more inlet valves are located at or near the centre(s) of the foam annuli.
6. 6. A pump as claimed in any preceding claim wherein the pump is adapted to inflate and forms part of a multi-layer support comprising a plurality of inter-Connecting laterally adjacent cells adapted to be inflated with fluid and having vertically stacked inter-communicating upper and lower chambers, with at least one such cell forming the pump chamber(s).
7. 7. An inflatable, multi-layer support cushion or pad comprising a plurality of cells generally of hour glass shape defined by vertically stacked inflatable upper and lower chambers and a centre neck position, the upper and lower chambers disposed in separate layers and the cells disposed in side-by-side relationship, channels and apertures provided inbetween for communication between the cells and chambers wherein at least one of said chambers or cells comprises a pump for inflating the cushion, the chamber or cell housing resilient material and having at least one non-return inlet valve and at least one nonreturn outlet valve in communication with the adjacent chamber(s) and/or cell(s).
8. 8. A method of producing an inflatable multi-layer support cushion with integral pump for inflating the cushion, the cushion having a plurality of cells formed by layers of flexible sheet materials comprising the steps of selectively coating the sheets with barrier material at locations to provide air flow channels, locating and securing the inlet valve(s) and outlet valve(s), providing apertures at predetermined locations on some of the sheets, placing the sheets in superimposed position inserting the foam material in the required positions and simultaneously sealing the sheet materials around the periphery and around the cells.
9. 9. A pump substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.