US3716934A

US3716934A - Press or flatiron surface

Info

Publication number: US3716934A
Application number: US00212586A
Authority: US
Inventors: H Wallsten
Original assignee: Inventing AB
Current assignee: Inventing AB
Priority date: 1971-12-27
Filing date: 1971-12-27
Publication date: 1973-02-20
Anticipated expiration: 1990-02-20

Abstract

The surface of an implement for ironing moistened material has an outer porous layer, preferably of sintered material, which permits steam to enter through its pores. A solid blocking layer separates the porous layer from a heating source, and passages within the implement permit the steam to exit at points removed from the moistened material.

Description

United States Patent Wallsten Feb. 20, 1973 PRESS OR F LATIRON SURFACE Hans Ivar Wallsten, Saffle, Sweden Assignee: AB Inventing, Saffle, Sweden Filed: Dec. 27, 1971 Appl. No.: 212,586

inventor:

Related U.S. Application Data Continuation-in-part of Ser. No. 62,428, Aug. 10, 1970, Pat. No. 3,659,347.

U.S. Cl ..38/93 Int. Cl. ..D06i 75/38 Field of Search ..38/93, 97

[56] References Cited UNITED STATES PATENTS 2,637,125 5/l953 Roberts ..38/97 3,228,126 1/1966 Pojol ..38/93 Primary ExaminerPatrick D. Lawson Attorney-Lorimer P. Brooks et al.

[5 7 ABSTRACT The surface of an implement for ironing moistened material has an outer porous layer, preferably of sintered material, which permits steam to enter through its pores. A solid blocking layer separates the porous layer from a heating source, and passages within the implement permit the steam to exit at points removed from the moistened material.

8 Claims, 3 Drawing Figures PAIENTEDmzmm Fig. 2

Fig. 3

PRESS OR FLATIRON SURFACE CROSS REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of my prior copending application Ser. No. 62,428 tiled Aug. 10, 1970 and titled Method and Means for Drying Moist Fibrous Material, Such as Paper, Cellulose, Other Fibers or the Like now US Pat. No. 3,659,347.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the press-drying of moistened materials, and more particularly to the surface layers of an implement for ironing cloth and the like.

2. Description of the Prior Art In the process of ironing, a heated surface, such as the surface of a flatiron, is brought into contact with moistened cloth or other material. In prior art ironing methods, the material has usually been moistened before ironing by spraying water on to the material from a separate container. When the so-called steam iron is used, water is applied to the material during the ironing process. The steam iron of the prior art typically has slots or openings formed in its ironing surface, and these openings communicate with a water reservoir located within the body of the steam iron for supplying water to the material ironed. With these prior art devices and methods it has been found difficult to effect uniform distribution of water over the entire surface of cloth to be ironed. Since an initial even distribution of water is necessary for good results, the prior art ironing systems are not wholly satisfactory. The rapid and uniform removal of steam from the ironed area is also highly desirable, but has not been readily achieved by the prior art.

SUMMARY OF THE INVENTION This invention solves the problems involved in the even distribution and removal of water during ironing by providing means for efficiently withdrawing water from an ironed surface in the form of steam. In an iron according to the invention the surface which comes into contact with cloth or other material has an outer surface layer of porous material, backed by an imperforate blocking layer.

In using the iron according to the invention the material to be ironed is first moistened thoroughly. When the hot porous surface of the iron is pressed against the material, steam is generated, but this steam escapes into the pores of the irons surface. Thus as the iron passes over the material, the water in the material is effectively removed in the form of steam taken up by the pores in the iron surface.

The solid blocking layer or barrier behind the porous surface limits the extent of travel of the entering steam. To permit escape of the steam in directions away from the surface where it was generated, there are channels or passages arranged either within the porous layer, or in the surface of the blocking layer. These passages guide the steam away in directions generally parallel to the iron surface.

The heat source of the iron according to the invention is located on the opposite side of the barrier or blocking layer from the surface which comes into contact with the material ironed. Thus there is a temperature gradient within the iron which causes the steam to expand as it travels inwardly through the porous layer,

forcing a draft of steam to pass through the internal BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawing:

FIG. 1 is a side view in perspective of a flatiron provided with an ironing surface according to the invention.

FIG. 2 is a view from below of the flat-iron of FIG. 1 with internal passages indicated by dashed lines.

FIG. 3 is a view in cross section of the lower part of a flat-iron having an ironing surface according to modification of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1 a flat iron having an ironing surface 2 according to the invention is generally designated by the reference character 1. The term ironing surface as used throughout this specification and in the appended claims, is intended to include not only the outer face of an ironing implement which comes into contact with the material to be ironed, but also to include some internal features which cooperate with the outer face of the implement in a manner to be described in detail. The planar outer contact face of the iron 1 is indicated by the reference numeral 5 in the drawings.

Referring now to FIG. 3 for a sectional view of the layers forming the surface 2 according to the invention, it will be seen that the contact face 5 of the iron is the lower face of a flat porous outer layer 3. Inwardly of the porous outer layer 3 there is a flat imperforate blocking layer 4 forming a steam barrier. The iron of FIG. 1 has layers 3 and 4 as in the modified form of iron shown in the sectional view of FIG. 3. A plurality of channels 6 pass transversely through the porous layer 3 and extend across the width of the iron to open at 7 to the surrounding air.

A conventional heat source such as an electrical heating element or the like (not shown in the drawing) is located in the body of the hand iron 1 and separated from the porous layer 3 by the barrier or blocking layer 4. This heat source inside the iron heats the blocking layer 4 and thus indirectly heats the contact surface 5 to the desired ironing or pressing temperature. When using the hand iron of the invention the cloth or other material to be pressed or ironed is first thoroughly dampened. Then the contact surface 5 is applied to the material in the usual manner. The water vapor generated by heating the moist material is continuously absorbed into the pores of the porous layer 3 and thence passes by way of the channels 6 to the ambient.

It has been found that sintered metal is an especially suitable material for the porous layer 3. Examples of metals from which the sintered material may be made are copper, copper alloys such as brass, sintered iron, steel, or alloys of iron or steel.

It is particularly important that the porosity of the material of the porous layer 3 be sufficient to permit entry and passage therethrough of steam, yet the material must be sufficiently strong to endure long use, and the surface must be smooth enough not to mark the cloth or other material ironed or pressed.

In order to produce the porous layer the sintered material must be formed of grains of a suitable size. Tests have shown that for so-called percent bronze a suitable grain size is less than 75 microns with an average grain size of 40 microns. This particle size is only given as an example since it will be feasible to use finer or coarser particle sizes depending to some extent upon the material used.

According to a'preferred embodiment of the invention the porous layer 3 may be formed of a plurality of thin layers, each of which has different properties. Thus the requirement of a smooth surface combined with low resistance to the passage of steam may be effectively achieved by having the outermost part of the porous layer 3 formed of very fine sintered material backed by successive sub-layers of relatively coarser sintered material in order to give the least possible resistance to the passage of steam. These several sub-layers may be combined prior to sintering to form the porous layer 3.

It is also possible to coat the contact face 5 by chromium plating or other surface treatment in order to achieve satisfactory hardness, but there must be pores in the surface which comes into contact with the moistened material.

The steam entering through the surface pores during ironing or pressing enters into the porous layer 3 and flows to the passages 6, which passages convey the steam away in a direction generally perpendicular to the temperature gradient induced in the porous layer. The expansion of the water vapor as it beats in passing inwardly through the layer 3 will help to push steam along the passages 6 and out through the apertures 7.

The passages 6 may be formed as an array of transverse parallel channels through the porous layer 3 extending across the iron parallel to the surface 5 as shown in FIG. 2. The entire iron surface 2 may have such passages or they may be formed through only a certain zone or zones of the iron surface 2.

A slightly different arrangement of passages is shown in FIG. 3, where some passages 6 are arranged as in FIGS. 1 and 2 and other passages 6a are located inwardly of the passages 6. The passages 6a are located right at the interface between the blocking or barrier layer 4 and the porous layer 3. As shown in FIG. 3 there are registering grooves in the layers 3 and 4 which mate to form the passages 6a. The passages 6a also run transversely across the iron surface 2 and open to the ambient at openings 8 on both sides of the iron.

The structure according to the invention is highly suitable for use as the entire surface 2 of a hand iron, but it will be apparent that a surface constructed according to the invention could also be used in only certain zones of a hand iron surface, with an ordinary imperforate surface in other zones of the contact surface.

The surface of ll'Ol'lll'lg or pressing devices other than hand irons can also be advantageously constructed according to the present invention, with a porous outer layer and an imperforate blocking layer or barrier between the porous layer and the heat source. Other modifications and adaptations of the ironing surface within the spirit and scope of the invention will suggest themselves to those of ordinary skill in the art.

What is claimed is:

I. In an ironing implement for i'roning moist material such as cloth or the like, an ironing surface including a porous outer layer having an outer contact face for ironing engagement with moist material, the pores of said porous layer affording entry to water vapor generated by the evaporation of the moisture from said material, a barrier layer lying inwardly of said porous layer for blocking the inward passage of water vapor beyond said ironing surface, passages located inwardly of said contact face for passing water vapor received through the pores in directions generally parallel to said contact face.

2. An arrangement according to claim 1 in which said outer porous layer is formed of sintered material.

3. The arrangement according to claim 1 in which said outer porous layer is formed of sintered metallic material, the composition of said layer being such that the contact face of the porous layer consists of fine sintered material for smoothness, whereas the interior of said porous layer consists of relatively coarser sintered material having lower resistance to flow of water vapor than said fine sintered material.

4. The arrangement of claim 1 wherein said passages extend transversely through said porous layer for discharging water vapor to the ambient remotely from the point of generation of said water vapor.

5. An ironing implement for heat pressing of moist material, including a heat source, a porous outer layer having a contact face for pressing engagement with said moist material, and a barrier layer separating the heat source from the porous layer, said barrier layer serving to conduct heat from said heat source to said porous layer, so that during ironing moisture in said moist material is vaporized and enters said porous layer as water vapor, and transversely directed passages through said porous layer for passing said water vapor in directions generally perpendicular to a temperature gradient caused by the supply of heat to said porous layer.

6. The ironing implement of claim 5 wherein said porous layer is formed of sintered metallic material.

7. The ironing implement of claim 5 wherein said contact face is flat and smooth, said porous outer layer is composed of sintered material, the outermost portion of said porous layer being of fine sintered material and the interior portion of said porous layer being of relatively coarser sintered material.

8. The ironing implement of claim 5 wherein said passages comprise a plurality of channels opening at their ends to the ambient for discharging said water vapor.

Claims

1. In an ironing implement for ironing moist material such as cloth or the like, an ironing surface including a porous outer layer having an outer contact face for ironing engagement with moist material, the pores of said porous layer affording entry to water vapor generated by the evaporation of the moisture from said material, a barrier layer lying inwardly of said porous layer for blocking the inward passage of water vapor beyond said ironing surface, passages located inwardly of said contact face for passing water vapor received through the pores in directions generally parallel to said contact face.