GB2141490A - Pneumatic pump - Google Patents

Abstract

A pneumatic hand operated pump comprising two tubular members (2, 4) arranged to be slideable one within the other in close contiguity, an air outlet nozzle (6) which is provided at one end of the two tubular members and an air inlet aperture (28) provided in the other of the two tubular members, a first valve (8) fitted in the nozzle (6) and arranged to permit air to pass out of the nozzle (6) but to resist air flow into the nozzle (6), and a second valve (23) associated with the air inlet aperture (28) and arranged to permit air to pass into the said other of the two tubular members from atmosphere but to resist air flow in the opposite direction, whereby consequent upon execution of sliding reciprocatory movements between the two tubular members a pneumatic pumping effect is produced which results in the expulsion of air from the nozzle (6). <IMAGE>

Description

SPECIFICATION Pneumatic pump This invention relates to pneumatic hand operated pumps. More especially it relates to such pumps for inflating balloons.

It is an object of the present invention to provide a balloon pump which is inexpensive to produce and yet efficient in operation.

According to the present invention a pneumatic hand operated pump comprises two tubular members arranged to be slideable one within the other in close contiguity, an air outlet nozzle which is provided at one end of one of the two tubular members and an air inlet aperture provided in the other of the two tubular members, a first valve flitted in the nozzle and arranged to permit air to pass out of the nozzle but to resist air flow into the nozzle, and a second valve associated with the air inlet aperture and arranged to permit air to pass into the said other of the two tubular members from atmosphere but to resist air flow in the opposite direction, whereby consequent upon execution of sliding reciprocatory movements between the two tubular members a pneumatic pumping effect is produced which results in the expulsion of air from the nozzle.

The nozzle is preferably arranged to receive a balloon. The nozzle may be provided with ribs over which the neck of a balloon fits in use of the pump.

The first and second valves may each comprise a flat valve seat, a valve aperture in the valve seat, a cage surrounding the valve seat, and a flat obturating member retained within the cage and effective to occlude the valve aperture consequent upon valve operation.

The cage may comprise a plurality of upstanding members which are arranged around the valve aperture to form an enclosure within which the obturating member is positioned and retained, so as to be free to move towards the valve seat or away from the valve seat in accordance with the direction of airflow through the valve aperture which is formed in the valve seat.

The first valve may comprise a valve insert having a slightly tapered generally cylindrical body portion in one end of which the valve seat is formed.

The said other of the two tubular members may be provided with an end wall in which the air inlet aperture is formed, the inside surface of the end wall being arranged to serve as a valve seat.

The said one of the two tubular members which embodies the nozzle may be arranged to be slideable over the said other of the two tubular members.

The outer cylindrical surface of the said one of the two tubular members adjacent the nozzle may be formed to provide a hand grip, and the outer cylindrical surface of the said other of the two tubular members adjacent the end wall thereof may be also formed to provide a hand grip.

Each of the two tubular members may be formed by an injection molding process.

The said one of the two tubular members which embodies the nozzle may be formed by an injection molding process which is commenced from the end remote from the nozzle.

The obturating member-may comprise a disc of resilient material. The resilient material may be a rubber material or a plastics material.

The various parts of the pump may be fabricated from a plastics material.

One embodiment of the invention will now be described solely by way of example with reference to the accompanying drawings in which: Figure 1 is a perspective view of a balloon pump; Figure 2 is a perspective view of a valve insert for the balloon pump shown in Figure 1; Figure 3 is a perspective view of a further valve insert for the ballon pump shown in Figure 1; and Figure 4 is a perspective view of a valve obturator member forming a part of the valve insert shown in Figures 2 and 3.

Referring now to Figure 1, a balloon pump comprises two generally tubular members 2 and 4. The tubular member 4 is arranged to slide in close contiguity within the tubular member 2 but in an alternative arrangement the tubular member 2 may be arranged to slide in close contiguity within the tubular member 4. The tubular member 2 is formed at one end with a nozzle 6 into which a valve insert 8 is inserted and is retained therein.

The valve insert 8 is shown in greater detail in Figure 2. The tubular member 4 is provided with an end wall 10. The end wall 10 has upstanding members 11 which are formed on the end wall 10 and which surround an aperture 1 3. The upstanding members 11 are provided with buttress reinforcing portions 12.

The valve insert 8 comprises a slightly tapered but generally cylindrical body portion 14, one end of which is closed to define a valve seat 1 6 in which a valve aperture 1 8 is formed. The valve aperture 1 8 is surrounded by a cage defined by upstanding members 20 within which an obturating member 22, as shown in Figure 4, is enclosed. The obturating member 22 is formed of a resilient material.When the valve insert 8 is inserted in the nozzle 6, the aperture 1 8 is occluded by the obturating member 22 thereby to prevent air from entering the tubular member 2 but to permit air to flow from the tubular member 2 through the aperture 1 8. The valve insert 8 is a friction fit in the nozzle 6 and it is secured in place by heat deforming the inside surface of the nozzle 6 in the area 6A to bring the inside surface of the nozzle 6 over the adjacent end of the valve insert 8.

Referring now to Figure- 3, the valve insert 23 shown therein is the same as the valve insert 8 shown in Figure 2. Thus the valve insert 23 comprises a slightly tapered generally cylindrical body portion 24, one end of which is formed to define an end portion 26 in which an aperture 28 is formed. The aperture 28 is surrounded by a cage defined by upstanding members 30. The members 30 are inserted in the cage formed by the members 11. The members 11 are longer than the members 30 so that the members 11 extend beyond the end 32 of the valve insert 23. The members 11 are then deformed by heat treatment at their ends thereof so as to retain the valve insert 23 in position. A disc obturating member 22 is then retained in the cage formed by the members 30 and the obturating member 22 can float between the end wall 10 and the end portion 26.

The cylindrical members 2 and 4 are provided with hand grips 32,34 respectively as shown. These hand grips 32,34 are formed by an injection moulding process. The tubular members 2 and 4 are formed from the ends 36 and 38 respectively whereby the internal parts of the moulding tool (not shown) are supported during the moulding process. It has been found that by effecting the moulding operation as just before described from the ends 36 and 38 respectively a generally parallel cylindrical member can be formed without the need for tapering as may normally be required in order to facilitate removal of the tubular members 2 and 4 from the moulding tool.

As the tubular members 2,4 are pulled apart, air will enter the tubular member 4 through the aperture 13 and through the spaces formed between the members 11 and 30. As the tubular members 2, 4 are pushed together, the obturating member 22 will close the aperture 1 3 and air will be pumped along the tubular member 2 and out through the aperture 18. As the tubular members 2,4 are pulled apart again, the pumped air cannot be sucked baclt into the pump as the obturating member 22 of the valve insert 8 will block the aperture 18.

A pump as just before described can be fabricated inexpensively and is particularly efficient in operation for balloon inflation since valve inserts are provided one at each end.

The balloon easily fixes over ribs 40 formed around the nozzle 6. When the balloon (not shown) has been inflated, it can then be pulled off the ribs 40 and sealed.

It is to be appreciated that the embodiment of the invention described above has been given by way of example only and that modifications may be effected. Thus, for example, the valve inserts 8,23 could be of a different shape.

Claims (14)

1. A pneumatic hand operated pump comprising two tubular members arranged to be slideable one within the other in close contiguity, an air outlet nozzle which is provided at one end of one of the two tubular members and an air inlet aperture provided in the other of the two tubular members, a first valve fitted in the nozzle and arranged to permit air to pass out of the nozzle but to resist air flow into the nozzle, and a second valve associated with the air inlet aperture and arranged to permit air to pass into the said other of the two tubular members from atmosphere but to resist air flow in the opposite direction, whereby consequent upon execution of sliding reciprocatory movements between the two tu bular members a pneumatic pumping effect is produced which results in the expulsion of air from the nozzle.

2. A pneumatic hand operated pump according to claim 1 in which the nozzle is arranged to receive a balloon.

3. A pneumatic hand operated pump according to claim 2 in which the nozzle is provided with ribs over which the neck of the balloon fits in use of the pump.

4. A pneumatic hand operated pump according to any one of the preceding claims in which the first and second valves each comprise a flat valve seat, a valve aperture in the valve seat, a cage surrounding the valve seat.

and a flat obturating member retained within the cage and effective to occlude the valve aperture consequent upon valve operation.

5. A pneumatic hand operated pump according to claim 4 in which the cage comprises a plurality of upstanding members which are arranged around the valve aperture to form an enclosure within which the obturating member is positioned and retained. so as to be free to move towards the valve seat or away from the valve seat in accordance with the direction of airflow through the valve aperture which is fomed in the valve seat.

6. A pneumatic hand operated pump according to any one of the preceding claims in which the first valve comprises a valve insert having a slightly tapered generally cylindrical body portion in one end of which the valve seat is formed.

7. A pneumatic hand operated pump according to any one of the preceding claims in which the said other of the two tubular members is provided with an end wall in which the air inlet aperture is formed, the inside surface of the end wall being arranged to serve as a valve seat.

8. A pneumatic hand operated pump according to any one of the preceding claims in which the said one of the two tubular members which embodies the nozzle is arranged to be slideable over the said other of the two tubular members.

9. A pneumatic hand operated pump according to any one of the preceding claims in which the outer cylindrical surface of the said one of the two tubular members adjacent the nozzle is fored to provide a hand grip, and the outer cylindrical surface of the said other of the two tubular members adjacent the end wall thereof is also formed to provide a hand grip.

10. A pneumatic hand operated pump according to any one of the preceding claims in which the two tubular members are formed by an injection moulding process.

11. A pneumatic hand operated pump according to any one of the preceding claims in which the said one of the two tubular members which embodies the nozzle is formed by an injection moulding process which is commenced from the end remote from the nozzle.

1 2. A pneumatic hand operated pump according to any one of the preceding claims in which the obturating member comprises a disc of resilient material.

13. A pneumatic hand operated pump according to claim 1 2 in which the resilient material is a rubber material or a plastics material.

14. A pneumatic hand operated pump substantially as herein described with reference to the accompanying drawings.