GB2116034A

GB2116034A - Warm-air hand drying apparatus

Info

Publication number: GB2116034A
Application number: GB08304440A
Authority: GB
Inventors: John William Postbechild
Original assignee: Smiths Group PLC
Current assignee: Smiths Group PLC
Priority date: 1982-03-02
Filing date: 1983-02-17
Publication date: 1983-09-21
Also published as: GB2116034B; GB8304440D0

Abstract

Such apparatus comprises means for producing a flow of air, fluid fed heat exchange means 31 for heating the air forming said flow of air, and an air outlet through which the flow of heated air is discharged on to the hands of a user. An installation including a plurality of such apparatus, in which case one heat exchanger is provided for each apparatus and the exchangers are preferably fed via a pump (32) from a common reservoir in the form of a hot water tank (33). In one convenient form, the apparatus of the installation are interconnected to form an elongated trunking having hand drying stations spaced along its length, with the common reservoir 33 at one end of the trunking and pipes 35 for the heat exchangers running through the trunking. <IMAGE>

Description

SPECIFICATION Warm-air hand drying apparatus This invention relates to warm-air drying apparatus and, in particular, to warm-air drying apparatus for drying hands or other parts of the body, of the kind comprising means for producing a flow of air, heating means for heating the air forming said flow of air, and an air outlet through which the flow of heated air is discharged on to the hands of the user.

The invention also relates to installations including such drying apparatus.

In our co-pending Patent Application No. 8304439 there is described and claimed such warm-air hand drying apparatus which is characterised in that said means for producing the flow of air comprises an air moving device operable by compressed gas (preferably air), and in that control means are provided operable by a user, to control the supply of compressed gas to the air moving device.

In said co-pending Application, it is proposed that the heating means may comprise either an electrical heating element, or a heat exchanger through which, for example, hot water is circulated.

According to the present invention warm-air drying apparatus of the kind referred to above is characterised in that the heating means comprises a heat exchanger to and through which a heated fluid is circulated from an appropriate source.

Thus, although heat exchanger arrangement may be part cularly advantageous when fitted together with an air moving device, insofar as the plumbing for the air moving device and heat exchanger may be carried out at the same time, nevertheless, according to the present invention, an improvement can be obtained, in respect of known apparatus of the kind referred to, in both energy saving and safety. Furthermore, in the case of a warm air installation comprising a plurality of warm-air hand drying apparatus, preferably one heat exchanger would be provided for each apparatus and the heat exchangers would be connected so as to be supplied with heated fluid from a common reservoir, for example, a hot water boiler.With such an arrangement significant energy savings could be achieved compared with known installations, which normally comprise a series of independent dryer units, each with an electric heating arrangement.

Conveniently, in such an installation, the housings of the drying apparatus may be defined by separating plates within a generally elongated trunking to provide hand drying stations spaced at intervals along its length, and the common reservoir and associated equipment such as a pump, etc. located at one end of said trunking, in which case the pipework connecting the reservoir and the heat exchangers would conveniently run through the interconnected housings.

In order that the invention will be readily understood one embodiment of a warm-air drying installation will now be described, by way of example, with reference to the single Figure in the accompanying drawing, which is a fragmentary front elevational view of the installation, the embodiment being suitable for installation in the washroom of a factory, offices, or similar.

Referring to the Figure, the hand dryer installation comprises a plurality of housings 27 defined in an elongated trunking, which is appropriately divided by a separating plates. Each station of the installation, defined by a housing 27, includes heating means in accordance with the invention, an electrically driven fan (not shown), preferably a centrifugal fan, for creating a flow of air, associated with the heating means, an air outlet nozzle 28 through which heated air flow is discharged when the fan is actuated, and which is rotatable to direct that air flow on to a user's hands or face, and a manuallyoperable push-button switch 29 (or proximity sensor) for controlling the operation of the fan and also the heating means.An air inlet grill 30 is provided in each housing 27 through which ambient air is drawn by the fan to flow over the heating means when the respective station is in use.

In this embodiment said heating means comprises a heat exchanger matrix 31 to which heated liquid medium is circulated by means of a pump 32 controlled in accordance with operation of the mutually-operated switch or proximity sensor. The liquid medium may be hot water derived from, for example, a washroom's hot water supply system.

However, the manner in which this hot water is circulated and also the temperature level at which it is set may make this impracticable in many situations. Therefore, particularly where a plurality of hand drying stations are provided as in the case of this embodiment, the hot water is supplied from an independent gas or oil fired water boiler, or a thermally-insulated hot water tank 33 (as shown) having electric immersion heaters 34, said hot water being fed through respective pipes 35 to the heat exchange matrix 31 at each of the hand drying stations. Thus, the heated water is stored in a tank located remote from the heat exchangers, where it is maintained at a desired temperature level (e.g. of the order of 200 F) by thermostatic control of the immersion heaters.To maintain water equilibrium in the tank 33, the main water supply 36 may be fed via a top-up tank 37 and expansion pipe 38 to the tank 33. With all the hand drying stations in their inoperative condition, the arrangement permits hot water from the storage tank to circulate through the heat exchanger matrices under thermosiphon action so that there tends to be a build up of static heated air around each heat exchanger matrix. Thus, when one of the electric switches 29 associated with a hand dryer station is pressed to actuate the pump and circulate hot water through the respective heat exchanger matrix 31, and the fan, there will be no delay in available heat for the heat flow from the respective apparatus, since static heated air around the matrix is immediately available to the user. In an alternative arrangement, it is envisaged that a respective solenoid valve may be disposed in the hot water supply pipe to each heat exchanger and arranged to open in accordance with actuation of the electrical switches of the associated hand dryer stations so that hot water is pumped through only the heater exchanger matrices of those hand dryer stations which have been activated.

As shown in the Figure, the use of an elongated trunking to define spaced housings 27 can be readily mounted on, for example, an existing wall of a wash-room where available space may be at a premium, conveniently with a drying station positioned above a respective wash basin 40.

Claims

1. Warm-air drying apparatus of the kind comprising means for producing a flow of air, heating means for heating the air forming said flow of air and an air outlet through which the flow of heated air is discharged on to the hands of a user, characterised in that the heating means comprises a heat exchangerto and through which a heated fluid is circulated from an appropriate source.

2. Warm-air drying apparatus according to Claim 1, characterised in that each said heat exchanger comprises a matrix.

3. Awarm-airdrying installation comprising a plurality of warm-air hand drying apparatus according to Claim 1 or 2, each with a respective heat exchanger, characterised in that the sourceforthe heated fluid comprises a common reservoir.

4. Awarm-airdrying installation according to Claim 3, characterised in that said common reservoir comprises a hot water boiler.

5. A warm-air drying installation according to Claim 3, characterised in that said common reservoir comprises a thermally insulated hot water tank, and in that a pump is provided which is actuated to pump hot water through the heat exchangers when a drying apparatus is activated by a user.

6. A warm-air drying installation according to any one of Claims 3 to 5, characterised in that the hand drying apparatus is interconnected so as to form a generally elongated trunking having hand drying stations spaced at intervals along its length, and in that the common reservoir is located at one end ofthetrunking.

7. A warm-air hand drying installation comprising a plurality of warm air hand drying apparatus substantially as hereinbefore described with refer enceto, and as illustrated in the Figure, of the accompanying drawing.

7. A warm-air drying installation according to Claim 6, characterised in that the hot water pipes for connection to the heat exchangers are contained within and run through the trunking.

8. A warm-air drying apparatus, or a warm-air drying installation comprising a plurality of such apparatus substantially as hereinbefore described with reference to, and as illustrated in the Figure, of the accompanying drawing.

New claims or amendments to claims filed on 14 June 1983.

Superseded claims 1-8.

New of amended claims:

1. A warm-air hand drying installation comprising a plurality of warm-air hand drying apparatus of the kind comprising means for producing a flow of air, heating means for heating the air forming said flow of air and an air outlet through which the flow of heated air is discharged on to the hands of a user, characterised in that the heating means for each apparatus comprises a heat exchanger to and through which a heated fluid is circulated, and in that the source for the heated fluid comprises a common reservoir.

2. A warm-air drying installation according to Claim 1, characterised in that the hand drying apparatus are interconnected so as to form a generally elongated trunking having hand drying stations spaced at intervals along its length, and in that the common reservoir is located at one end of the trunking.

3. Awarm-air drying installation according to Claim 2, characterised in that the hot water pipes for connection to the heat exchangers are contained within and run through the trunking.

4. A warm-air drying installation according to any of claims 1 to 3, characterised in that each said heat exchanger comprises a matrix.

5. A warm-air drying installation according to any one of claims 1 to 4, characterised in that said common reservoir comprises a thermally insulated hot water tank, and in that a pump is provided which is actuated to pump hot water through the heat exchangers when a drying apparatus is activated by a user.

6. A warm-air drying installation according to any one of claims 1 to 4, characterised in that said common reservoir comprises a hot water boiler.