Hand operated inflator

Claim 2

A hand operated inflator for pumping air into an inflatable device and for controlled release of air from the device comprising: a) a resilient bulb (10); b) a valve member (12) connected to the bulb (10) and having an outlet (32) for connection to the inflatable device (16); and c) a first one way valve (47) in said valve member arranged to permit flow of air to the outlet (32) when the bulb (10) is squeezed; characterised by: d) a second one way valve (42) in said valve member (12) communicating with ambient air and arranged to admit air to the bulb (10) so that it can recover its shape after being squeezed; and e) a passage (48) in the valve member (12) by-passing both the first and second one way valves (47,42) and connected to a pressure release valve (18) on the bulb (10) remote from the valve member (12), which can be manually operated to release air from the inflatable device.

Claim 3

An inflator as claimed in Claim 1, in which the release valve is connected to the by-pass passage by a flexible tube within the bulb.

Claim 4

An inflator as claimed in Claim 1 or Claim 2, in which the release valve (18) includes a spring-loaded plunger (20) positioned at one end of the bulb (10) so that it can be depressed by an operator's thumb when the operator's hand remains in a convenient position for squeezing the bulb.

Claim 5

An inflator as claimed in any one of the preceding claims, wherein a filter (44) is placed in the path of air passing from ambient through the second one way valve (42) to the bulb (10).

Claim 6

An inflator as claimed in any one of the preceding claims, wherein the valve member (12) is a single block (30) having a first passage (48) therethrough which by-passes the first and second one way valves (47,42), a second passage (46) therethrough containing the first one way valve (47) and a third passage (34), the third passage containing the second one way valve (42) and communicating with the atmosphere.

Claim 7

An inflator as claimed in Claim 5, wherein the first and second passges (48,46) both lead into a common bore (32) in the block.

Claim 8

An inflator as claimed in Claim 6, wherein a tube (14) leading to the inflatable device (16) is received in the common bore (32).

Claim 9

An inflator as claimed in any one of Claims 5 to 7, wherein the block (30) is received in a sleeve at one end of the bulb (10).

Claim 10

An inflatable lumbar support unit comprising a hand operated inflator as claimed in any preceding claim and a cushion (16) which has an inflatable chamber (68) surrounding an area (66) which is not inflatable, the inflator being arranged to inflate the cushion.

Claim 11

A unit as claimed in Claim 9, wherein the area (66) of the cushion which is not inflatable is of a dog-bone shape.

Claim 12

A unit as claimed in Claim 9 or 10, wherein the chamber (68) is generally oval.

Claim 13

A unit as claimed in Claim 11, wherein the ends (70) of the oval are, when inflated, fatter than the sides (72).

Claim 14

A unit as claimed in any one of claims 9 to 12, and made of two sheets (60,62) of material selectively bonded together.

Claim 15

A unit as claimed in Claim 13, wherein the material is rubber.

Claim 16

A motor vehicle seat with a lumbar support unit as claimed in any one of claims 9 to 14, wherein the cushion is in the seat backrest and the hand operated inflator is accessible to an occupant of the seat, for inflating the cushion.