CH655783A5 - Hot-air device for drying installations - Google Patents

Description

The present invention relates to a warm air device for drying systems, in particular laundry drying rooms or chambers, with a blower and with a heater in the flow of the sucked-in outside air, for generating a circulating air which absorbs moisture in the drying room.

It is a tiresome fact that with today's types of buildings, the space that allows housewives to dry their laundry is becoming increasingly scarce. The applicant has therefore been offering warm air devices of the aforementioned type (CH Patent No. 334 550) for a number of years, which allow moist laundry to be dried effectively within the smallest space volumes.

Warm air tumble dryers of this type, which can interact with a laundry drying cabinet or with a normal drying room, constantly supply fresh air to the room, as a result of which moist, saturated exhaust air can leave the drying room. The heating for the fresh air intake is usually controlled in such a way that full heating is only required at the start of drying, when most of the water has evaporated, in order to increase the room temperature so that the circulating air can remove more moisture.

In addition to the drying problems, problems have arisen in the energy supply which have led to the object of the present invention to design a warm air device of the aforementioned type in such a way that both the required amounts of energy and the operating costs of such laundry drying devices can be considerably reduced.

This is now achieved according to the invention in that the inflow-side air duct of the blower is guided via a heat exchanger which is in flow communication with the drying chamber via an outward-opening return line for returning an energy-giving circulating air component.

s By means of these measures according to the invention, it is thus possible to use the waste heat from the recirculating air that comes out to preheat the fresh air drawn in, thus effectively relieving the heating. Internal measurements in comparison to the known prior art have shown that the measures according to the invention can now reduce the amount of energy now required in KWh / KgHzO by more than half, the comparison measurements, of course, with the same amount of circulating air in m3 / h; Fresh air volume (m3 / h); Room temperature (° C); Dehumidification (Kg / hHaO); Operating time (h); Amount of laundry (kg) and water content were made.

The hot air device according to the invention can be designed as a built-in unit for a drying room or can be firmly integrated in a laundry drying cabinet or in a tumbler.

For further energy equalization, the warm air device according to the invention can also be designed such that the upstream air duct between the blower and the heat exchanger is in flow connection with the drying chamber via a bypass line.

Furthermore, it is expedient if the outflow-side air duct of the blower passes through a heating device, in which case the heating device can be regulated via a thermostat in the drying room in order to maintain a room temperature that is as constant as possible.

In order to be able to throttle the amount of fresh air with decreasing absolute air humidity, it is provided that there is a hygrostatically controllable air flap arrangement in the upstream air duct of the blower.

35 In order to be able to further regulate the ratio between exhaust air through the return line and air flow through the bypass line, it is expedient if there is also a preferably hygrostatically controllable air flap arrangement in the return line. In this case, a further control can take place in that there is another fan in the return line.

For example, embodiments of the subject matter of the invention are explained in more detail below with reference to the drawing.

45 It shows:

Fig. 1 in a schematic functional representation of the hot air device according to the invention as a compact unit for a laundry drying room or cabinet;

2 shows the hot air device according to the invention as an integrated component of a laundry drying cabinet; and

Fig. 3, the hot air device according to the invention as an integral part of a tumbler.

55 The warm air device configured as a compact structural unit or built-in unit in FIG. 1 for a laundry drying room or cupboard or the like indicated by the dash-dotted lines comprises a blower 2 in a construction frame 1, the outflow-side air duct 3 of which passes through a heating device 4, to preheat the air to be blown into the drying room. Here, the heating device 4 can be switched by a room thermostat 5 via the control line 6.

According to the inflow-side air channel 7 of the 65 blower 2 is guided via a heat exchanger 8, which is in flow connection with the drying chamber via an outward-opening return line 9 for returning an energy-giving circulating air component.

3rd

655 783

The heat exchanger 8 can be of any type. However, a heat exchanger consisting of wave-like elements stacked on top of one another, which are separated from one another by flat intermediate walls, has been found to be alternately arranged crosswise. Such a heat exchanger is described in detail in CH patent 610 648 (owned by the company).

In the mouth 10 of the upstream air duct 7 there is also an air flap arrangement 11, which can be controlled in a manner not shown by a room hygrometer in order to be able to regulate the inflow of fresh air as a function of the changing absolute humidity of the room air.

Furthermore, an air flap arrangement 12 is also provided in the return line 9, which can be regulated, for example, synchronously with the air flap arrangement 11 in the opening 10 of the upstream air duct 7. A blower 13 in the return line 9 can serve as a further control means and can be controlled, for example, via the room hygrometer mentioned.

As can also be seen in FIG. 1, the upstream air duct 7, preferably between the blower 2 and the heat exchanger 8, is in flow communication with the drying chamber via a bypass line 14, which permits a further optimization of the operating conditions.

2 now shows the warm air device described above as an integrated component of a laundry drying cabinet,

the drying room 15 is shown recognizable by clothes 16. This arrangement also includes the upstream air duct 7 of the blower 2, which is guided over the heat exchanger 8. Here, too, the heat exchanger 8 is connected via s an outward-opening return line 9 for returning an energy-donating circulating air component to the drying chamber 15 in flow connection. Furthermore, the upstream air duct 7 between the blower 2 and the heat exchanger 8 is in flow communication with the drying chamber 15 via the bypass line 14.

The warm air device shown in FIG. 3 as an integral part of a tumbler also includes all the features according to the invention, for which reference is made to the same reference numerals for the elements described with reference to FIGS. 1 and 2. What differs from this arrangement according to FIG. 3 to the ones described above is that the bypass line has been dispensed with here.

In all cases, the warm air device according to the invention is a simply designed and therefore relatively inexpensive, efficient arrangement.

Here, of course, there are a number of design changes and additions within the scope of the invention. For example, further bypass lines and / or further flap controls can be provided in systems which require further limitations of the exchanger capacity in the transition seasons.

1 sheet of drawings

Claims (7)

655783 PATENT CLAIMS 1. Warm air device for drying systems, in particular laundry drying rooms or chambers, with a blower and with a heater in the flow of the sucked-in outside air, for generating a moisture-absorbing circulating air in the drying room, characterized in that the upstream air duct (7) of the blower (2) over a heat exchanger (8) is guided, which is in flow connection with the drying chamber via a return line (9) opening outwards for returning an energy-giving recirculating air component. 2. Warm air device according to claim 1, characterized in that the upstream air channel (7) between the fan (2) and the heat exchanger (8) via a bypass line (14) is in flow connection with the drying chamber. 3. Warm air device according to claim 1 or 2, characterized in that the outflow-side air duct (3) of the blower (2) passes through a heating device (4). 4. Warm air device according to claim 3, characterized in that the heating device (4) via a thermostat (5) is controllable in the drying room. 5. Warm air device according to claim 1 or 2, characterized in that in the upstream air duct (7) of the blower (2) and / or in the return line (9) is a hygro-statically controllable air flap arrangement (11 or 12). 6. Warm air device according to claim 1 or 2, characterized in that there is a further fan (13) in the return line (9). 7. Use of the warm air device according to claim 1 as a built-in unit for drying rooms or as part of drying cabinets or tumblers.