US2309179A - Domestic appliance - Google Patents

Description

Fig 2 INVENTOR. /fZI/ l m;

ATTORNEYS Jan' 26, 1943- D. K. FERRls DOMESTIC APPLIANCE Filed June 29,' 1940 `a 26 inch shoe is heated.

Patented Jan. 26, A1943 UNITED STATES PATENT oFFicE 2,309,179 .DOMESTIC APPIJANCE Y Donald K. Ferris, Dayton, eral Motors Corporation, Dayton, Ohio, a corporationof Delaware Ohio, assignor to Gen- -Applic'ation .Tum 29,1940, serial No. 343,199 l 3 claims.. (ci. 33.66)

This invention relates to a domestic appliance andmore particularlyto ironing devices and machines.

When heat is applied in the conventional manner to the side of an ironing member opposite the tivelygreat and particularly lserious in the long ironing shoes used on ironing machines. These shoes will become bowed or distorted as much as one thirty-second of an inch or more when This bowingor distortion causes the shoe to bear only upon the ends of the roll when heated and little or. no

ironing pressure is provided lat the middle of the roll. This prevents proper ironing of fabrics and causes the padding of the roll to be packed down more tightly at the ends of the roll.

It is an object of my invention to providefan ironing surface which Will remain substantially straight when hot or cold. l'

It is a further object of my invention to provide' an ironing shoe for' an ironing machine whichl will remain substantially straight at all teni'- peratures.

It is another object of my invention to reducev the bowing and deformation of an ironing shoe under temperature changes.

It is another object of my invention to provide an ironing shoe with a bi-metal construction for reducing the bowing and deformation caused by temperature changes.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawing, wherein a preferred form of the present inventi-on is clearly shown.

In the drawing:

Fig; 1 is a perspective view or an ironing machine embodying one form of my invention;

Fig: 2 is a vertical sectional view through a portion of the ironing machine shown in'Fig. 1; Fig. 3 is a sectional View of a portion of the roll and shoe taken -along the lines 3-3 of Fig. 2; and

Fig. 4 is a view of the rear face of the ironing shoe with its cover removed.

vided at one end with a head 22.

Briefly, I have shown an ironing machine which' is provided with an ironing shoe formed of stainless clad steel with the stainless steel surface adjacent the ironing surface of the shoe. Pref- 5 erably, the stainless steel is provided with a hard chromium plating.

Referring now more particularly to the draw` .ing there is shown in Fig. 1 an ironing machine provided with a table member 20 which is pro- Thehead 22` supports the roll 24 and the shoe 26. The operation of the roll and the shoe is controlled by a switch means 2B land a knee control 30.

More specifically, as is better shown in Fig. 2,

the roll is rotatably supported upon a fixed tube L3`2 extending from the head 22.

A ball bearing including `an inner race 34 and an outer race 36 rotatably supports the transverse disk 38 which at its edges suports a steel cylinder 40 forming a part of the roll 24. Padding 42 surrounds this steel cylinder 40 and fabric 44 is provided over the padding to complete the roll. Two or m'ore bearing supports may be provided for supporting the roll upon the fixed tube 32. The roll 24 is driven `by a drive shaft 46 also extending from the head 22. and connecting to the roll 24 near its outer end. This drive shaft 46 is preferably connected through some suitable clutching means with an electric motor provided in or beneath the head 22.

The ironing shoe is supported upon a tube 48 extending from the head which may be rotated in order to apply the ironing shoe 26to the roll.

At thecenter of the shoe, .this tube 48 is provided with a shoe support member 50 preferably rotat' ably mounted upon the tube 48. This support member. 5U is provided at its upperend with a pin 52 which provides a pivotal connection with the ironing vshoe 26 and which also pivotally supports a hand lever having an operating arm 54 provided with a bell handle 5' and an extension 58 extending in the opposite direction from the pivot pin, which, when in the operating position, as shown in Fig. 2, applies a force to deflect l a comparatively rigid leaf spring 60 which is fixed in a slot in Vthe tube 48 and held in position by a screw 62. Thus the force applying the shoe to the roll is controlled by the tension of the leaf spring Eiland thev angular position of the tube 48 which may be rocked -to apply the shoe to the roll or to release the shoe from the roll. The tension of the leaf spring 60 may be regulated by the setscrew 64 which is threaded into the support 50 and engages the leaf spring 80 near its base.,

' mercial product edge of the shoe is fastened an electric resistance heating element 12 in the form of long metal zigzag strip of suitable resistance material which is held between the electrical insulation, prefer-ably in the form of sheets of mica'designated by the reference character 14. A metal member 16 extends substantially over the entire length of the electrical resistance heater 1.2 and its insulation and is firmly held in place by the s-crews 18. These screws 18 have .their heads recessed in the ironing member and extend through the electric heating member 12 and the metal strip 16 4into the threaded thmbles 8i] which clamp the steel strip and the electrical heater 'tightly to the ironing member 10.

The cover 82 for the ironing shoe 2S is held in place by the screws 84 which have their heads recessed in the cover 82 and which are threaded into the closed end 'of the threaded thimbles 80. A bracket 8B provides the connection between the pivot pin 52 and the metal strip 16 which is connected to the ironing member 10. An adjustable thermostat 88 provided with an externaladjusting knob 80 is provided within the shoe adjacent its leading edge for controlling the energization of the electric strip type heater 12. Some suitable form of insulation is provided within the shoe 26.

One of the problems in an ironing machine,-

such as has just been described, is the dimculties caused `by the warping or distortion of the ordinary shoe when heated. This is believed to be caused by the fact that the inner surface of the ironing member corresponding to the member 10 is at the higher temperature when heated 'than its opposite surface which is in contact with the surface of the roll. The surface of the roll as well as the material being ironed, takes away heat from the ironing member and thus provides a temperature differential between the opposite surfaces of the ironing member. This causes a difference in the total thermal expansion of the ironing member causing the ironing member to bow down at a higher pressure to be This causes applied by the ends of the ironing member upon the ends of the roll but the center of the roll receives little or no pressure. This creates an undesirable ironing condition.

Some attempts have been made to overcome this condition by not making the shoe straight initially vbut to make the shoe so that it is bowed inthe opposite direction when cold. However, this expedient is not altogether satisfactory since it does not provide a uniform pressure when the ironing machine is operated when not heated up.

Frequently an ironing machine is operated in a cold condition for demonstration or test purposes.

In order to overcome this condition I have constructed an ironing member 10 in such a way that t' it will remain straight whenv hot or cold. I have done this by making ironing member 10 of stainless clad steel with. a stainless steel portion 92 forming the ironing steel backing 94 provides the opposite surface. By stainless clad steel I mean the ordinary comknown by that name which consists of a mild steel backing sheet, to one surface surface while the heavier` of which is weld d a'thinner stainless steel sheet. The backing sheet may be ordinary mild'carbon steel while the stainlessl steel facing may be any one of the nickel chrome stainless steels such as 8% nickel, 18% chrome, '1% nickel, 11% chrome, 9% nickel, 19% chrome. Each of these stainless steels has a coefficient of expansion of between 17 and 18 times 10-6 perfdegree centigrade. This construction has a bi-metal effect which compensates to a considerable degree for the bowing or warping which is normally' encountered in a shoe made of a single material. This is due to the bimetal effect of the stainless steel upon the ordinary steel backing. The stainless steel has a considerably higher coeflicient of thermal expansion than the steel backing used so that the use of this bimetal construction compensates for the temperature differential between the two surfaces of the ironing member.l For example, the coefficient of expansion may be in the proportion of 12 to 18. Thus, the steel backing has a coefficient of between 11 to 12 times 10-6 per degree centigrade while the stainless steel facing is between 17 to 18 times 10-6 per degree C. This difference is sufficient to provide a satisfactory amount of compensation. The relative thickness of the steel backing and the stainless steel may be varied in order to obtain the desired bimetal effect.- The total thickness may also be varied to regulate the bimetal effect. I prefer to use a shoe 1/8 or Tft; inch thick with comprising about one-fifth the total thickness'.

In addition to the bimetal effect the use stainless clad steel for an ironing member has other advantages. It provides a very durable surface which is rustless and remains bright. Preferably, the stainless steel surface is chromeplated, to improve its wearing properties. The stainless steel provides an excellent backing for the chrome plate. This construction is rustless, and wear and scratch resistant.

While the form of embodiment of the invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims.

What is claimed is as follows:

1. An ironing machine comprising a roll and a shoe adapted to contact a portion of the surface of the roll, the contacting surface of the shoe being formed of stainless clad steel, said stainless clad steel being formed of a layer of mild steel bonded to a layer of stainless steel, the stainless portion being located next to the roll and being about one-fifth the total thickness of the stainless clad steel for keeping the contacting surface `substantially straight when heated' or cold, and

means for applying heat to the side of the steel opposite the stainless portion.

2. An ironing machine'comprising a roll and a shoe'adapted to contact a portion of the surface of the roll, the contacting surface of the shoebeing provided by a composite sheet of metal, said composite sheet of metal including two layers of metallbonded together, the layers being different metals having substantially different coefficients of thermal expansion, the metal having the higher ccnicient of expansion forming the surface layer, means for applying heat to the side of thecomposite sheet opposite thesurface layer, the relative thicknesses of the different metals of the composite sheet being proportioned to keep the contacting surface of the shoe substantially straight when heated or cold.

DONALD K.

the stainless steel facing Y of the.

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