GB2219808A - Heating and damping clothes press - Google Patents

Abstract

A clothes press includes two facing pressing surfaces for pressing clothes, one of the surfaces 4 being heatable. An ultrasonic transducer 8 vapourises water at ambient temperature in a vapour generating chamber 6. A fan 9 mixes the vapour with air and blows it through apertures 14 in one of the pressing surfaces. Heating element 4 may be moved into a cushioning layer. A control circuit activates vapouriser 8 for a few minutes during the heating period. <IMAGE>

Description

CLOTHES PRESSES This invention relates to clothes presses and has particular but not exclusive relevance to portable trouser presses.

Known types of trouser press remove unwanted creases from trousers by heating them between two relatively movable surfaces; the same process ensures that wanted creases are improved.

It has long been known that the presence of steam when pressing clothes greatly improves pressing performance. In the case of pressing irons this facility is provided by a steam generating chamber. However, the use of steam injection devices in trouser presses has proved to be unsuccessful due to factors such as difficulties in controlling the steam generation and the running of clothes dyes caused by the high temperature of the steam. Furthermore there is a safety hazard present resulting from the steam being generated at an above ambient pressure.

It is therefore an object of the present invention to provide a clothes press having improved pressing performance but wherein the problems of steam injection devices are avoided.

According to the present invention there is provided a clothes press comprising at least two pressing members having substantially flat facing surfaces between which clothes are pressed, at least one of the members having means for heating the clothes positioned against the one members facing surface means for generating water vapour at substantially ambient temperature and means for assisting circulation of water vapour through the press.

Thus the invention provides a clothes press with a moisture injection facility to improve the performance of the press, this injection facility not being a steam injection facility and consequently not having the aforementioned disadvantages of a steam injection facility.

Preferably, the means for generating the water vapour comprises an ultrasonic transducer.

Such a transducer is an effective device for generating water vapour and is particularly suitable for use in the press of the invention because of its compact size and controllability: as soon as the transducer is turned on it starts to generate water vapour, as soon as it is turned off it stops.

Preferably, the heating means of the press is controlled by an electronic control circuit, which controls the heating means so as to set the temperature of the heating means and the time for which it operates.

The provision of an electronic circuit provides the user with a choice of heating programmes, each having a different operating temperature and length of heating cycle.

Preferably, the water vapour generating means and water vapour circulating means are controlled by a further electronic control circuit, which ensures that water vapour is generated and circulated at a predetermined rate. It is desirable that the electronic control circuits for controlling the heating means and the water vapour generating and circulating means are combined on a simple printed circuit board. Thus all the operating parameters of the clothes press are controlled by a single, compact printed circuit board.

In a preferred embodiment of the invention the water vapour generating means and circulating means are incorporated into one of the pressing members. Preferably, a water reservoir is incorporated into the same pressing member as the water vapour generating means and circulating means.

Thus, by incorporating the water vapour generating and circulating means into one of the pressing members a compact, portable arrangement is provided. The addition of a water reservoir removes the necessity to frequently refill the water vapour generating means.

Two clothes presses in accordance with the invention will now be described, by way of example only with reference to the accompanying drawings of which: Figure 1 shows a schematic side elevation of a first clothes press embodying the invention Figure 2 shows a schematic side elevation of a second clothes press embodying of the invention; Figure 3 shows a cross-section taken along the line X-X' in Figure 2; Figure 4 shows a cross-section taken along the line Y-Y' in Figure 3.

A clothes press, shown in Figure 1, comprises a press body 1 and front panel 2 which are hinged together at 3 by a hinge mechanism (not shown). Press body 1 is provided with a heating area 4 which preferably comprises a cushioned outer portion with a heating element woven into its underside. A pair of retaining arms 5 arranged on either side of the press body 1 and front panel 2 prevent the front panel 2 from falling to a horizontal position.

An ultrasonic vapour generating chamber 6 filled with water 7 is provided with an ultrasonic transducer 8 and fan 9 and is connected to the front panel 2 by tubes 10 and 11. A control circuit (not shown) is also provided which controls the operation of the press, including operating conditions such as temperature and lengths of heating time. The circuit is activated by a push button mechanism or rotary knob (not shown). Additionally or alternatively a program selector can be provided which enables the user to select different programs and hence different operating temperatures and lengths of heating times, depending on the type of material to be pressed.

The control circuit also controls the transducer 8 and hence the generation of water vapour in the chamber 6.

Thus during operation of the clothes press an item of clothing or material is clamped between the press body 1 and front panel 2 by movement of the front panel 2 towards the press body 1. Panel 2 is held in place against press body 1 by a conventional fastening means (not shown).

The user activates the control circuit by depressing the push button mechanism or by selecting a programme with the programme selector. The heating element 4 then heats up to a predetermined operating temperature and maintains this temperature for a predetermined length of time or 'cycle', which is usually around thirty minutes, since this has been found to be the optimium length of time for effectively pressing clothes.

Once the heating element 4 has heated up to its operating temperature the control circuit then activates the ultrasonic transducer 8 which vaporizes the water 7 in the vapour generating chamber 6. The fan 9 mixes this vapour with air and blows it up the tube 10 into a cavity 13 in the front panel 2. Boles 14 in the panel 2 enables the vapour/air mixture to pass into the fabric of the article of clothing or material clamped between the press body 1 and front panel 2. Any excess vapour in the cavity 13 condenses and is returned to the generating chamber 6 by means of the tube 11, entering through inlet 12. The presence of water vapour during the pressing process causes the material fibres to relax, while the clamping pressure flattens the material and defines the crease line; continued heating dries the fabrics in their new position. The presence of water vapour during the pressing process increases the performance of the press considerably. The vapour is injected for only a short period of time during the heating cycle and is controlled by an electronic control circuit. As mentioned above it is preferred that the heating element control and the vapour generating control are combined as part of the same electronic circuit and this may be done by combining them on the same printed circuit board.

Typical operating conditions of the press are: a heating cycle of thirty minutes, a vapour injection period of between one and two minutes; a transducer 'misting' rate of 10 gram per minute, giving an injected quantity of 10-20 g; and a heater temperature of 80-85 0C. The heater temperature is higher than in 'dry' presses because the higher temperature helps dry the material after the injection cycle and any possible damaging effects due to the higher temperature are offset by the cooling effect of the vapour. It is also preferable to preheat the press for ten minutes prior to vapour injection, since this improves pressing performance.

Experiments have shown the above operating parameters to be the optimum operating parameters.

The results of performance of the press under varying operating conditions are shown in Tables 1 and 2 which follow.

crease sharpness/radius (mm) cycle time press operating temperature (deg.C) (mins) 60 70 80 90 5 5 - - 10 5 5 4 4 15 5 4 3 3 20 5 2.5 1.75 2 25 4 2 1.5 1.5 30 4 2 1.5 1.25 35 4 2 1.5 1.25 TABLE 1 crease sharpness/radius (mm) vapour quantity press operating temperature (deg.C) (gms) 60 70 80 90 0 4 2 1.5 1.25 8 2.5 1.5 1.25 1.0 16 2.5 1.5 1.25 1.25 24 2.75 2 1.5 1.25 40 - 2.5 1.5 TABLE 2 Table 1 shows the performance of the clothes press under various operating temperatures and heat cycle times in terms of 'crease sharpness'. Crease sharpness was measured using radius gauges ranging from 1 mm to 5 mm in steps of 0.25 mm. Press operating temperatures were governed by a feedback control and were set with the aid of thermocouples placed between the press body 1 and front panel 2.

These results show that increasing the length of the heating cycle to 30 minutes improves crease sharpness, as does increasing the press operating temperature with the best results being obtained between 70 0C and 900C. However, it is often undersirable to use such high operating temperatures, since such temperatures may damage the material being pressed, this being particularly so in the case of woollen materials.

Table 2 shows the performance of the clothes press under various operation temperatures and with various amounts of water vapour being injected into the press. Once again, performance was assessed in terms of crease sharpness i.e. the external radius formed by the crease and measured with radius gauges. The smaller the measured radius, the sharper the crease. The tests were carried out for heating cycles of 30 minutes. The transducer generated vapour at a fixed rate of 8 grams per minute.

The results obtained for zero vapour quantity correspond with results obtained during the dry pressing tests. In general these results show that, compared with dry pressing, vapour injection improves crease sharpness and hence performance of the press, the optimium amount of vapour being 8-16 grams, corresponding to a one to two minute injection period.

In particular the improvements in performance obtained by vapour injection are most obvious at lower operating temperatures of 60-800C thus making it unnecessary to use high temperatures in order to obtain good results, as is the case in dry pressing.

In addition, the presence of water vapour makes it possible to use higher operating temperatures, if required, without damaging the material being pressed, since the water vapour has a cooling effect.

Thus the clothes press of the present invention provides means whereby the water vapour can be introduced into the material of the clothes during pressing, improving the performance of the press compared to conventional 'dry' presses, particularly at low operating temperatures, and reducing damage to the material at high operating temperatures, while at the same time overcoming the disadvantages associated with trying to introduce moisture into such a press by using steam generation.

While in the embodiment described above, the vapour injection and press temperature are controlled electronically, a timer and thermostat arrangement could be used instead.

Figures 2 to 4 show a preferred, compact, embodiment of the invention where parts corresponding to the same parts described in Figure 1 will be numbered correspondingly.

In this embodiment of the invention the heater 4 is incorporated into the front panel 2 instead of the press body 1 and the vapour generating chamber 6, transducer 8 and fan 9 are all built into the back of the press body 1 to provide a compact and more easily portable arrangement.

As before the fan 9 blows water vapour generated in the vapour chamber 6 into tube 10 which in this embodiment conducts it to a cavity 15 in the press body 1. Holes 16 in the press body 1 enable the water vapour to pass into the fabric of an article of clothing or material clamped between the press body 1 and front panel 4. Excess water vapour condenses and is returned to the chamber 6 by the tube 11, as before.

A water reservoir 17 is also provided in the press body 1 to supply water to the vapour generating chamber 6. The water reservoir 17 is filled through a tube 18 which has a cap 19, the water from the reservoir 17 passing to the vapour generating chamber by means of tube 20. A constant water level is maintained by an inlet valve 21 in combination with a float mechanism 22.

The water may alternatively be maintained at a constant level by means of a valve using the well known Zbell jarw principle.

As with the first embodiment, the time of the heating cycle and the vapour injection is preferably electronically controlled by a combination of circuits on a printed circuit board. The press may have just one operating cycle or may be provided with a program selector with a variety of programs to choose from; it may be wall mounted or provided with detachable feet for a freestanding option; conveniences such as a tray to hold pocket contents, a contained jacket hanger and a pull out tie rack may also be provided as could a 'clothes ready' buzzer.

The press body 1 and front panel 2 are preferably made by structured foam moulding or injection moulding using reinforced plastic resins such as Noryl (Registered trademark) manufactured by G.E. Plastics or MinIon (Registered trademark) manufactured by Dupont.

A woven heating element moulded into the front panel 2 during manufacture is preferred; pressed or extruded metal side rails are provided to accommodate the hinge and clamping mechanism and to strengthen the body. A top cover (not shown) for housing the electronic controls is provided and is preferably injection moulded using unreinforced thermoplastic resin such as Acrylonitrile-Butadiene-Styrene. The pocket controls tray is either incorporated into this moulding or supplied in a clip-on feature. The jacket hanger and feet which are detachable, can either be of one Bslot-int type or secured by screws. Both jacket hanger and feet are preferably moulded in reinforced thermoplastic resin as for the press body.

While in this embodiment the vapour generating chamber 6 and its associated parts, are built into the press body 1 they could instead be built into the front panel 2 with the heater 4 incorporated into the body 1. However, this is less desirable since the added weight of the ultrasonic transducer, vapour generating chamber and so on would put a strain on the hinge mechanism (not shown) connecting the front panel 2 to the press body 1 at point 3 and also on returning arms 5.

Claims (13)

1. A clothes press comprising at least two pressing members having substantially flat facing surfaces between which clothes are pressed, at least one of the members having means for heating clothes positioned against the one members facing surface means for generating water vapour at substantially ambient temperature and means for assisting circulation of water vapour through the press.

2. A clothes press according to Claim 1 in which the means for generating water vapour is an ultrasonic transducer.

3. A clothes press according to either of the preceding claims in which the means for circulating the water vapour includes an electric fan effective to blow water vapour through an array of holes in one of the pressing members.

4. A clothes press according to any one of the preceding claims in which the water vapour generating means and circulating means are incorporated into one of the pressing members.

5. A clothes press according to any one of the preceding claims in which the water to be vapourised is held in a water reservoir connected to the means for generating water vapour.

6. A clothes press according to Claim 5 in wbich the reservoir is incorporated into one of the pressing members.

7. A clothes press according to Claim 5 or Claim 6 in which the flow of water from the reservoir to the means for generating water vapour is controlled by an inlet'valve in combination with a float mechanism.

8. a clothes press according to any one of Claims 5, 6, or 7 including a means for returning excess water vapour to the reservoir.

9. ' A clothes press according to any one of the preceding claims in which an electronic control circuit controls the heating means so as to set the temperature of the heating means and the time for which it operates.

10. A clothes press according to any one of the preceding claims in which a further electronic control circuit controls the rate of vapour generation and the rate of vapour circulation.

11. A clothes press according to any one of the preceding claims in which the means for heating comprises a heating element woven into the underside of the facing surface of said one member.

12. A clothes press according to any one of the preceding claims wherein the pressing members are joined and hinged at one end.

13. A clothes press substantially as herein described with reference to the accompanying drawings.