Patent GB-905649-A (GB)
Title: Infant incubator
IPC: A61G11/00
Filed: 1959-10-20
Abstract: 905,649. Infant incubators. AIR-SHIELDS Inc. Oct. 20, 1959 [May 12, 1959], No. 35555/59. Class 81 (2). An infant incubator comprises a base member including a plurality of chambers in which air is treated before passing to the occupant space. As shown, Fig. 1, the base B comprises a housing 8-12 supporting, with a gasket 15 interposed, a unitary casting 14 which includes a mixing chamber 17, a heating chamber 18, a dry air or cooling chamber 19 and a humidifying chamber 20. A removable deck D covers the casting 14 and supports a mattress M, and a cover C is hinged to the base and rests on a tubular gasket 57 of flexible plastics material. Air entering the incubator through a filter FR, Fig. 2, passes to the housing 24 of a fan 91 driven by a motor 93. To obtain air from outside the building, an alternative filter with a coupling for a pipe may be substituted for the filter FR. Air returned from the occupant space to the chamber 17, to which may be added a controlled supply of oxygen at 117, 118, enters the housing 24 at 94. The fan 91 forces air into the chamber 18 which has a loose cover 29 and contains an electric heater 28. The chamber 18 communicates at 26, 27 with chambers 19 and 20. The chamber 19 is located above an insulated ice chamber 32 fed from a hopper 39. The humidifying chamber 20 has a combined filling and draining invertible pipe and level-indicating device 44. The proportion of air delivered to the occupant space from the chambers 19 and 20 respectively is controlled by a delivery member H adjustable from outside the incubator over apertures 58, 59 in the deck D which communicate with the chambers 19 and 20 respectively. The member H has baffles 83, 84 and its movement is limited by stops 77a, 77b on the deck so spaced that the aperture 59 is never completely closed. Adjusting means comprise a shaft 86 which is movable axially inwards so that a finger 88 rigid with the shaft engages a pin 90 on the member H and then rotated. The member H delivers the air stream at a level at least as high as the upper edge of a cross-plate 66 which limits longitudinal movement of the infant and not more than half-way between the surface of the mattress M and the roof of the cover C and the air flow speed should be not greater than 25 ft./min. in the region up to 4-6 inches above the mattress. There are small outlet vents 146 in the cover C. A cross-plate 67 prevents the blockage of a return duct 61 leading to chamber 17 where the recycled air is mixed with oxygen if required. Located partly in the duct 61 is a gas-filled adjustable thermostat 123, connected by a capillary tube 125 to a bellows and plunger 126 having a control knob 127, which acts through a relay 128 to turn the heater 28 on or off when the temperature of the returned air falls below or exceeds a desired value. A safety thermostat 124 overrides the thermostat 123 and turns off the heater 28 when a predetermined temperature is reached and actuates a buzzer and a light 137. Both thermostats, the heater 28, the fan 91 and motor 93 are mounted on a vertical board (not shown) detachable as a unit. To prepare the incubator for use, the fan 91 is turned on which lights up a bulb 136, the electric power being supplied through a cable 130, and the thermostat control knob 127 is adjusted to switch on the heater 28 which lights up a bulb 135. When the required temperature is reached in the occupant space, as shown by a thermometer 142, the knob 127 is turned just far enough to switch off the heater which is henceforth controlled by the thermostat 123 and the safety thermostat 124,