EP0995831A1

EP0995831A1 - Ironing board with steam exhauster

Info

Publication number: EP0995831A1
Application number: EP98119933A
Authority: EP
Inventors: Nicola Settimo
Original assignee: Settimo Diffusion Sas
Current assignee: Settimo Diffusion Sas
Priority date: 1998-10-21
Filing date: 1998-10-21
Publication date: 2000-04-26
Also published as: DE29820145U1

Abstract

Ironing board with steam exhauster, which can be utilized in combination with an iron with steam generation, provided with a solenoid valve for steam flow.

Ironing board comprising control means (12; 41) for the exhauster (9), associated to the solenoid valve and adapted to control such exhauster (9) depending on the operative condition of the same solenoid valve. Different versions of the control means are provided.

Advantages : the steam is steadily sucked and eliminated as long as the iron is operating, without the need of manual interventions.

Description

The invention refers to an ironing board with steam exhauster, fit to produce the automatic operation of such exhauster and consequently the elimination of the same steam contemporaneously to the connection of the iron used for the ironing on such board.
There are known ironing boards for ironing clothing articles, utilized in combination with irons with steam generator and provided with exhauster for the elimination of steam which is produced during the ironing phase, in order to maintain dry the clothing articles also after the ironing phase.
Generally, these ironing boards are provided with a pedal control, which is connected in the exhauster electric circuit, separately from the electric circuit of the iron, which is operated by the foot for producing the connection and disconnection of the same exhauster respectively at the beginning and the end of the ironing phase.
Therefore, the so realized ironing boards, require a particular care by the operator for being able to operate the exhauster so as to eliminate the steam, and therefore are not fit for performing such function in the case of omission of operating the pedal or not correct use of the ironing board by the user.
The present invention has the object to prevent with safety the above mentioned inconvenience to take place, by means of an ironing board realized so as to connect and disconnect automatically the exhauster respectively at the beginning and the end of the ironing phase of clothing articles onto such ironing board, thereby ensuring a high reliability to this kind of apparatuses.
This object is obtained, according to the invention, by means of an ironing board with incorporated exhauster for the steam elimination which is realized with the substantially described constructive characteristics with particular reference to the attached claims.
The invention will be better understood from the following description given by way of not limitative example only and with reference to the accompaning drawings, in which:

Fig. 1 shows schematically a perspective view of an ironing board according to the invention, in a first embodiment thereof;
Figs. 2 and 3 show an electric block diagram of the ironing board represented in Fig. 1, on two possible versions thereof;
Fig. 4 schematically shows a perspective view of an ironing board according to the invention, in a second embodiment thereof;
Fig. 5 shows an electric block diagram of the ironing board represented in Fig. 4.

In the Fig. 1 it is represented schematically an ironing board 5 for ironing clothing articles, in a first embodiment thereof, which is utilized in combination with irons with steam generation (not shown) of per se known kind, such ironing board comprising substantially an ironing plane 6 with horizontal extent joined to a proper support structure 7 of folding kind, for resting it onto the ground, and provided with electric heating resistances 8 and at least an exhauster 9 for the steam developed during the ironing phase, which is driven by at least an electric motor 10 connected in the electric circuit of this appliance together with the electric resistances 8, to at least a temperature regulator such as a thermostat 11 or the like, adapted to control the switching on or off of such resistances so as to maintain the temperature of the ironing board and therefore of ironing of the clothing articles within pre-established limits, and a control circuit 12 acting with the above mentioned electric components and made in the manner and for the functions hereinafter described.
Finally, such ironing board is provided with a support table 13 articulated laterally thereto and assigned for supporting the relative iron with steam generation, which can be displaced from this extended position for supporting the iron to a position folded and laid on the ironing plane 6, in the condition in which the ironing board isn't utilized for the ironing phase.
In the Figs. 2 and 3 it is shown schematically the composition of two different control circuits 12, based substantially upon the principle to sense the operative condition of the solenoid valve (not shown) incorporated in the iron, so as to permit or not permit the steam flow from the steam generator through the same iron, so as to cut in or off automatically the motor 10 of the exhauster 9 respectively when such solenoid valve is energized (and therefore the steam is flowing through the iron), with consequent suction and elimination of such steam, or de-energized (and therefore the steam isn't flowing through the iron), in the condition in which no steam is developed and therefore the suction and elimination thereof isn't required.
With reference to the version shown in the Fig. 2, this control circuit is made preferably by a card provided with electric and electronic components subdivided in a first measuring circuit (block 14) provided with two inputs 15 and 16 connected in parallel to the mains in order to measure the electric mains voltage adequately filtered from the produced noises, by generating at its output 17 a low d.c. voltage electric signal which is proportional to such voltage, a second measuring circuit (block 18) provided with two inputs 19 and 20 connected in series to the appliance electric circuit so as to measure the flowing electric current which is variable depending on the inductive circuit load formed by the heating resistances 8 and the steam control solenoid valve, by generating at its output 21 a low d.c. voltage electric signal which is proportional to such current, a multiplier circuit 22 whose inputs 23 and 24 are respectively connected to the output 17 of the first measuring circuit 14 and the output 21 of the second measuring circuit 18, in order to determine the input level during the ironing phase depending on the above mentioned inductive load, so as to generate at the output 25 of such multiplier circuit an electric signal which is proportional to the output level respectively measured.
Moreover, such multiplier circuit 22 is connected with its output 25 to the input 26 of a comparison circuit (block 27), arranged for performing the comparison between the electric signal generated at the output 25, which as already stated is variable depending on the electric output respectively absorbed by the above mentioned inductive load, and an electric signal corresponding to an electric output absorbed by the heating elements 8 with or without energization of the steam control solenoid valve, and such that to vary from a lowest to a greatest level thereof depending on the connection of the heating elements alone or of these latter together with the solenoid valve, so that at the output 28 of such comparison circuit 27 an electric signal dependent on this comparison is generated, which signal provides for controlling the connection or disconnection of the electric motor 10 of the exhauster 9 through a suitable electric control circuit 29 of per se known timed type, depending on the result of the same comparison.
To this aim, the comparison circuit 27 is so calibrated as to generate at its output 28 such an electric signal as to keep the motor 10 off, and therefore also the exhauster 9 stopped, in the condition in which the appliance is operating and the measured electric output corresponds with that one absorbed by the heating resistances 8 alone, and said solenoid valve is de-energized so that no steam for ironing is developed, and to determine automatically the connection of the motor 10 and therefore the operation of the exhauster 9 when the level of the measured electric output is the same of that one developed by the connection of the heating resistances 8 and said solenoid valve, which is energized, so that the ironing steam is developed and consequently sucked and eliminated instantaneously by such exhauster 9.
In the version of control circuit 12 shown in the Fig. 3, it is noted that this circuit is always made preferably as a card provided with electric and electronic components, also in this case subdivided in a voltage measuring circuit 14 and a current measuring circuit 18, connected like the previously described circuits and generating at the respective outputs 17 and 21 low d.c. voltage electric signals which are proportional to these quantities.
Such voltage measuring circuit 14 and current measuring circuit 18 are also connected with the respective outputs 17 and 21 to the corresponding inputs 30 and 31 of a phase difference measuring circuit 32, adapted to sense the instantaneous changes of the electric signals generated at the outputs of the above mentioned measuring circuits and corresponding to the instantaneous changes of the phase difference between the so measured voltage and current, depending on the changes of the inductive load composed of the heating resistances 8 and said solenoid valve. In addition, this phase difference measuring circuit 32 is provided with an output 33 connected to a first input 34 of a logic circuit of conventional type, in the present case constituted by an AND gate 35, and is so set as to generate at both the output 33 and the first input 34 always a determinate logic level whatever phase difference is measured, independently from the changes of the above mentioned inductive load.
Moreover, the present control circuit is also constituted by a load sensing circuit 36, connected on the one hand to the output 21 of the current measuring circuit 18 and the input 31 of the phase difference measuring circuit 32, and on the other hand to a second input 37 of the logic circuit 35, adapted to sense steadily the level of the specified inductive load, so as to apply to this input 37 a logic level corresponding to the respectively sensed load level, in a manner to provide for a determined logic level which remains unchanged until the sensed level is maintained within a pre-established limit, in the condition in which the appliance is out of commission or is operating and the heating resistances 8 alone are connected and the solenoid valve for steam is de-energized, so that the ironing steam isn't developed, and a different logic level in the condition in which the appliance is operating and the heating resistances 8 are connected and the solenoid valve is energized, so that the steam is developed and therefore the suction and elimination thereof is required.
In turn, the logic circuit 35 is connected with its output 38 to the motor 10 of the exhauster 9, through a control circuit 39 of per se known timed type, so as to be able to control the connection or disconnection of the same exhauster depending on the logic state of the output 38, determined by the logic levels applied from time to time to the inputs 34 and 37 of such logic circuit and depending on the condition of load provided in the appliance electric circuit.
In this way, as long as the inputs 34 and 37 of the logic circuit 35 attain a determinate logic level, when the steam solenoid valve is de-energized, the output 38 of the logic circuit attains such a logic level as to maintain the exhauster 9 stopped, while as soon as one of such inputs (in this case the input 37) attains a different logic level, when said solenoid valve is energized and thus the steam is developed in the appliance, said output 38 too attains a different logic level, so that the exhauster 9 is set at work which therefore provides for sucking and eliminating the steam, and such an exhauster remains connected for a time pre-established in advance even after the ironing phase is ended, in order to permit a complete steam absorption and thus maintain dry effectively the fabric covering the ironing board and also the clothing articles laid thereon.
Turning now to the Fig. 4, in which an ironing board 5 according to the invention is represented in a second embodiment thereof, it is noted that such board is substantially composed of the same component parts of the board described in the Fig. 1, and with respect thereto it comprises further at least a pair of adequate moisture sensors 40 of per se known electric type, housed internally the ironing board covering fabric, or also in different positions in the ironing board, preferably closely into contact with such fabric so as to be able to sense the moist or dried condition thereof, and which are connected to a control circuit 41 for the exhauster motor 10, which will be described later in detail, so that to cause the connection and disconnection of such motor depending on the moist conditions of the same fabric, thereby ensuring an effective ironing of the clothing articles.
To this aim, the moisture sensors 40 are adapted to sense the fabric moist condition by measuring the change of either the electric resistance of such fabric, or of the capacitive impedance formed between the pair of sensors (acting as capacitor plates) and the material of the ironing board covering fabric, which is proportional to the content of moisture absorbed by such fabric.
In the Fig. 5 it is schematically shown the composition of the control circuit 41, which also in this case is made preferably by a card provided with electric and electronic components, subdivided in an adapter circuit 42 provided with two inputs 43 and 44 connected to the moisture sensors 40 and supplied with the mains electric voltage, which is adequately filtered from the noises thus generating at its output 45 an electric signal corresponding to the electric resistance or the capacitive impedance of the ironing board fabric which has been respectively sensed, which in turn corresponds to the moisture content of the same fabric, as well as a measuring circuit 46 provided with an input 47 connected to said output 45 and provided for the comparison between the level of such electric signal and an electric reference signal of either pre-established level or variable level and proportional to the average trend of the moisture content, which signal is applied to a further input 48 of said measuring circuit and corresponds to a moisture content deriving from the steam generation, said measuring circuit being provided with an output 49 connected to the motor 10 of the exhauster 9 through a signal processing circuit 50 and a control circuit 51 of known type, and being adapted to generate at such an output 49 an electric signal depending on the result of such comparison, which signal is passed through the circuit 50 so as to be adequately processed and subsequently transmitted to the control circuit 51, which therefore provides for connecting and disconnecting the motor 10 of the exhauster 9.
In this way, as long as the measuring circuit 46 senses the presence of a moisture content smaller than the correspondent pre-established or variable level of said reference signal, such control circuit 51 provides for maintaining the exhauster stopped, while as soon as this moisture content tends to increase and attains the correspondent pre-established or variable level of said reference signal, the control circuit 51 provides to set at work said exhauster, with consequent suction and elimination of the steam.
Therefore, the so realized ironing board is able to ensure automatically and reliably the suction and elimination of the steam directly during the use of the iron, without the need of interventions by the user for the exhauster control, with consequent effective ironings of the clothing articles.
This ironing board is of universal type, in that it may operate with all types of irons, even those with instantaneous steam generation without boiler.
Finally, it is to point out also that the present ironing board may be made also in a different and more simple constructive system, by connecting to this aim the exhauster motor electric supply system in the electric circuit of the solenoid valve, which in turn is controlled by means of a manual operated push-button incorporated in the iron, wherein such connection is obtained by means of an auxiliary outlet mounted on the body of the steam generation boiler, separated from the iron, to which the exhauster electric supply cable is connected.
In this way, such push-button serves to control contemporaneously both the iron and the exhauster, with consequent automatic connection of the same exhauster for the entire duration of the ironing phase. Obviously, also this version of ironing board may be coupled to a proper timer circuit of known type, thereby keeping the exhauster still connected for a determined time period after the ironing phase is ended, with consequent complete suction and elimination of the steam generated during the same ironing phase.

Claims

Ironing board with steam exhauster, which can be utilized in combination with irons with steam generation provided with steam emission regulating means such as a solenoid valve, comprising substantially an ironing plant with horizontal extent and a support structure situated below it, as well as electric beating means with thermostatic regulation, characterized by control means (12 ; 41) for said exhauster (9) which are associated to said regulating means and adapted to control said exhauster (9) depending on the operative condition of said regulating means.
Ironing board according to claim 1, characterized in that said control means (12) comprise a first measuring circuit (14) provided with inputs (15, 16) connected in parallel to the mains for measuring the electric voltage, which is adequately filtered from the produced noises, and an output (17) in which a low d.c. voltage electric signal is generated which is proportional to such mains voltage, a second measuring circuit (18) provided with inputs (19, 20) connected in series to the electric circuit of the same ironing board, so as to measure the flowing electric current, and an output (21) in which a low d.c. voltage electric signal is generated which is proportional to such current, a multiplier circuit (22) provided with inputs (23, 24) respectively connected to said outputs (17, 21) so as to determine the level of the output absorbed during the ironing phase, and an output (25) in which an electric signal is generated which is proportional to the output level respectively measured, and which is connected to the input (26) of a comparison circuit (27) adapted to compare the electric signal generated at said output (25) with an electric signal corresponding to the output absorbed by the electric circuit with or without connection of said regulating means, and such that to vary from a lowest to a greatest level depending on the connection condition of said heating elements and said regulating means, said comparison circuit (27) being provided with an output (28) connected to said exhauster (9) through an electric control circuit (29) of per se known timed type, and adapted to generate an electric signal depending on such comparison, such as to determine the disconnection or connection of said exhauster (9).
Ironing board according to claim 2, characterized in that said control means (12) comprise a phase difference measuring circuit (32) provided with inputs (30, 31) respectively connected to said outputs (17, 21) and adapted to sense the instanteneous phase difference between the voltage and current measured by the corresponding said first measuring circuit (14) and second measuring circuit (18), and an output (33) connected to a first input (34) of a logic circuit (35) of conventional type so as to generate a logic level corresponding to the presence or absence of such phase difference, which is provided with an output (38) connected to said exhauster (9) through a control circuit (39) of per se known timed type, as well as comprise a load sensing circuit (36) connected on the one hand to said output (21) and said input (31) and on the other hand to a second input (37) of said logic circuit (35) and adapted to apply to said second input (37) a logic level corresponding to the respectively sensed load level of the electric circuit, so as to determine the disconnection or connection of said exhauster (9) respectively when said regulating means are switched off or on.
Ironing board according to the previous claims, characterized in that said control means (41) comprise an adapter circuit (42) supplied with the adequately filtered mains voltage, and provided with inputs (43, 44) connected to moisture sensors (40) of per se known electric type, associated to the ironing board and adapted to sense the moist or dried condition by measuring the electric resistance or capacitive impedance thereof, as well as an output (45) in which an electric signal corresponding to the respectively measured electric resistance or capacitive impedance is generated, as well as comprise a measuring circuit (46) provided with an input (47) connected to said output (45) and an output (49) connected to said exhauster (9) through a signal processing circuit (50) and a per se known control circuit (51), and adapted to generate at said output (49) an electric signal depending on the comparison between the level of the signal generated at said output (45) and an electric reference signal of pre-established level or of variable level and proportional to the average trend of the moisture content, which signal is applied to a further input (48) of said measuring circuit (46), in a manner that said exhauster (9) is switched off or on depending on this comparison.
Ironing board according to the preceding claims, characterized in that said exhauster (9) is connected to said regulating means and is controlled together with these latter by means of manual operated control means associated to the respective iron.