US2415275A

US2415275A - Electrically heated ironing apparatus

Info

Publication number: US2415275A
Application number: US452696A
Authority: US
Inventors: William C Bruckman
Original assignee: Westinghouse Electric Corp
Current assignee: CBS Corp
Priority date: 1942-07-29
Filing date: 1942-07-29
Publication date: 1947-02-04
Anticipated expiration: 1964-02-04

Description

Feb. 4, 1947. w Q B U 2,415,275

ELECTRICALLY-HEATED IROiIING APPARATUS Filed July 29, 1942 14 r m /,a

INVENTOR WILLIAM C. BRUCKMAN.

m z :2 ATTORl Y Patented Feb. 4, 1947 ELEQTRICALLY HEATED IRONING APPARATUS William C. Bruckman, Yellow Springs, Ohio, as-

signor to Westinghouse Electric Corporation, East Pittsburgh, Pa, a corporation of Pennsyl- Vania Application July 29, 1942, Serial'No. 452,696

3 Claims. 1.

My invention relates to apparatus for ironing fabrics and the like and has for its primary object to provide improved apparatus of this kind.

A further object of the invention is to provide an improved ironer having an electrically-heated ironing member or shoe receiving energy from an electric circuit of limited capacity or wattage.

Further objects of the invention are to utilize,

substantially, all of the current available from' the circuit at all times that heating of the. shoe is effected; to uniformly apportion the current to the various heating means when the entire shoe is to be heated; and to apportion a greater quantity of the available current to the heating means associated with one portion of the shoe and a lesser quantity of the available current to a second portion of the shoe when said one portion requires heating and the second portion is idle, the amount of current apportioned to the idle portion of the shoe being just sufllcient to prevent excessive cooling thereof.

These and other objects are effected by my invention as will be apparent from the following description and claims taken in connection with the accompanying drawing, forming a part of this application, in which:

Figs. 1 and 2 are front and side elevations of one form of ironing machine constructed in accordance with m invention;

Fig. 3 is a diagram of the electrical connections for the heating means of the ironing machine; and,

Fig. 4 is a wiringdiagram of another embodiment of the invention.

The heating of the shoe of domestic ironing machines by electric energy derived from conventional, low wattage circuits of residences or the like presents a problem, especially when relatively large and damp articles are ironed, because of the heat drop in the ironer shoe at such times. The capacity of these circuits is limited because of fire underwriters regulations and many city ordinances which prohibit the fusing of these circuits above 15 amperes. The manufacturers of equipment of this kind have gone to considerable trouble and expended much money in an effort to increase ironer shoe efficiency in order to obtain the most useful heat from the power available.

Although 15 amperes may not be exceeded at any one time, this current may be used for any desired period of time, continuously if necessary, and the wattage distributed to the ironer shoe with greater effectiveness. In accordance with my invention, the shoe is provided with heating structures spaced apart longitudinally of the shoe for respectively heating spaced portions of the shoe, and these heating structures are controlled by switching means in such manner that the available power is divided between the heating structures for. uniformly heating the shoe when the entire shoe is being used for ironing large pieces. When only one end of the shoe is being used to iron small pieces or tubular garments, the heating structure at such end of the roll is energized at a high .rate and the other heating structure is energized at a low rate and the total amount of power being utilized at such times being equivalent, substantially, to the amount avail able. The unused end of the shoe is heated at a low rate at times when only one end of the shoe is used inorder to prevent excessive cooling of the unused end. Accordingly, the. time required to heat the unused endof the shoe to the temperature of the end which has been used, is reduced to a minimum. Furthermore, the heat loss from the end of the shoe being used through the shoe to the unused end thereof is reduced if excessive cooling of the unused end i precluded.

Referring now to the drawing, I have shown an ironer of conventional construction in Figs. 1 and 2, which ironer includes a base Ii! having an upstanding housing Il enclosing a driving mechanism (not shown) for the roll ii. The driving mechanism for the roll has not been shown in detail for the sake of brevity and since the-construction and operation of such apparatus is well understood in the art. Cooperating with the roll I2 is an ironer shoe l3, moved into and out of engagement with the roll in any well-understood manner. The shoe I3 is heated by suitable heating devices, diagrammatically shown at it and i5 and spaced longitudinally of the shoe [3. The structural details of the heating devices it and i5 form no part of'the present invention and have not been shownin detail. It will be understood, however, that these devices include resistance heating elements which translate electrical energy into heat and which are referred to hereinafter.

Referring now to Fig. 3, it will'be noted that the heating device I4 includes primary and secondary heating. elements [6 and I7, respectively, and that the heating device l5 includes respective primar and secondary heating elements it and [9. The ironer shoe I3 is represented diagrammatically by the rectangle shown in broken lines. Thermostatically-operated switches 2! and 22 respondto the temperatureof the respective spaced heated portions l4 and lEof the shoe I3 and con- 3 trol energization of the primary and secondary heating elements It to Is, inclusive.

Energization of the heating elements I6 to I9, inclusive, is controlled by a four-position switch, generally indicated at 23, and shown as a rotary drum switch in development. The switch 23 includes a plurality of movable contact segments 26 to 30, inclusive, carried by an insulating drum SI and cooperating with a plurality of stationary contact fingers 32 to 38, inclusive. The drum switch 23 is movable from an inactive'or ofi position, a shown in the drawing, to a plurality of active positions marked l," 2 and 3.

The source of power for the heating elements IE to I9 is represented by an electric circuit including conductors L1 and L2, which circuit is of limited capacity. It will be assumed that 1400 watts at He volts is available from said circuit. The conductors L1 and L are connected, respectively, to contact fingers 33 and 37 of the drum switch 23.

The contact finger 32 is connected by means of a conductor 38, in which the thermostat switch 2i is connected, to one terminal of each of the heating elements is and il. Likewise, the contact finger 3B is connected by means of a conductor 39, in which the thermostatically-operated switch 22 is connected, to one terminal of each of the heating elements I8 and I9. The opposite terminals of the heating elements It and I8 are tied together, as shown at M, and connected to the contact finger 35. The opposite terminals of the secondaryheating elements I? and I9 are connected, respectively, to the

contact fingers

35 and 38.

In the position or" the switch 23 as shown, all of the heating elements It to I9 are deenergized. If the operator desires to uniformly heat the shoe I3 throughout its length, the drum switch 23 is actuated to its No. 1 position wherein the elements I5 and I3 are energized. In this position of the drum switch 23, contact fingers 35 and 31 are bridged by the movable segment 25 and the

fingers

32, 33 and 3% are bridged by the segment 2d. Accordingly, a circuit is established from the conductor L1 to each of ,the

conductors

38 and 39 through the segment 2% and the fingers bridged thereby. The circuits then extend through the heaters I8 and I8 to the common connection ll and thence to the conductor L2 through the segment 25. The temperature of the shoe is governed by the adjustment of the thermostatic switches 2| and 22 in a well-understood manner.

Assuming that the operator desires to use only the end of the roll adjacent the heating structure is for ironing, the drum switch 23 is actuated to its No. 2 position. In this position,

fingers

32, 33 and 38 are electrically connected by means of the electrically-connected segments 26 and 28 and the

fingers

35, 35 and 37 are bridged by the segment 2i. In this position of the switch 23, the primary and secondary heating elements It and Il, respectively, of the heating structure I; are connected in parallel across the conductors L1 and L2 and the heating elements I8 and I9 at the opposite end of the shoe are connected in series across the conductors L1 and L2. In this No. 2 position of the switch 23, the conductor L1 is connected to one terminal of each of the elements it and Il through the movable segment 26 and conductor 38, and the opposite terminals of the heating elements I6 and I7 are tied together at the

contacts

35 and 36 by the segment 27. As the latter segment 21 is connected directly to the conductor L2, the parallel connection of the elements I6 and Il across the line L1L2 is completed. The series connection of the elements i8 and I9 includes the line conductor L1, the contact 33, the connected segments 26 and 28, contact 38 which is electrically connected to one terminal of the secondary heating element I9, the heating elements 39 and I8 in series, the common connection 4i and the fingers 36 and 31 which are bridged by the segment 2?, and the conductor L2.

Movement of the drum switch 23 to the No. 3

position establishes circuits similar to those just described, except that the heating elements I8 and I9 are connected in parallel and the heating elements l6 and II 'in series. In the third position of the drum switch, the

fingers

33, 34 and 35 are bridged by the segment 28 and the fingers 36, 37 and 3B are bridged by the segment 30. As the circuits through the heating elements may be clearly traced by reference to Fig. 3 of the drawing, a detailed description of the circuits is deemed unnecessary.

It Will be assumed that H00 watts of electrical energy is available from the circuit defined by the conductors L1 and L2. With this amount of energy available, the primary elements it and I8 may each be constructed to dissipate seven hundred watts of electrical energy into heat. The secondary heating elements ill and It are constructed to dissipate 435 watts of electrical energy into heat when directly connected across the conductors L1 and L2. Accordingly, when the drum switch 23 is in its No. 1 position wherein the elements I6 and I8 are connected in parallel to the circuit, a total of 1400 watts of energy is translated into heat and uniformly distributed to the shoe throughout its length. In the N0. 2 position of the control switch 23, the primary and secondary heating elements It and II are directly connected in parallel across the line conductors L1 and L2 and jointly translate 1135 watts of energy into heat for heating the end of the shoe adjacent thereto. At this time, the primary and secondary heating elements I8 and I9 are connected in series across the conductors L1 and L2 and jointly translate approximately 265 watts of energy into heat for preventing excessive cooling of their associated end of the shoe, which at this time is not being used.

In the No. 3 position of the control switch 23, the heat elements I8 and I9 being connected in parallel across the conductors L1 and L2 translate 1135 watts of energy into heat which is applied to their associated end of the-shoe. In the No. 3 position of the control switch 23, the heating elements It and I1, being connected in series across the supply circuit, translate 265 watts of energy into heat which is imparted to the end of the shoe associated therewith.

From the foregoing, it will be apparent that the shoe may be uniformly heated throughout its length by applying the total 1400 watts uniformly thereto at one time, and that 1165 watts may be utilized to heat one end of the shoe and 265 watts toheat the other end of the shoe which is idle, at other times. Accordingly, the portion of the shoe I3 which is being used may be rapidly heated and its temperature readily maintained by applying a relatively high wattage thereto. The purpose of applying a lower wattage to the unused end of the shoe is to prevent excessive cooling thereof so that when it is to be brought into active use, being at a moderately high temperature, it may be more quickly heated. Furthermore, by preventing excess cooling of the 15 unused end of the shoe, the transfer of heat from the portion of the shoe being used to the unused end thereof is substantially reduced.

In Fig. 4, I have shown another embodiment of my invention wherein the shoe is again rep-,

resented by the brolren rectangle l3 and heated by spaced heating structures i i iii. The heating structure it includes a primary heating element 4! and a secondary heating element 52, and the heating structure 55 includes a primary heating element 43 and a secondary heating element 441. The source of power is represented by an electric circuit of limited wattage, for exam ple, 1400 watts, and is designated Ll and L2. In this embodiment of the invention, an additional heating element shown at 35 extends throughout substantially the entire length of the shoe and is arranged when energized to impart heat uniformly to the shoe.

Energization of the various heating elements 41 to 45, inclusive, is controlled by a multi-position switch it generally constructed along the lines of the switch 23 described heretofore. The switch 46 includes a plurality of stationary contacts 4? to 53, inclusive, which. cooperate with movable contact segments 5% to 59, inclusive, carried by an insulating drum St. The drum Si is movable from an off position, as shown in the drawing, to three active positions designated (1,: 2,; and 3 1 In this embodiment of the invention, it will be assumed that each of the elements ii, 52, 43 and i4 is designed to translate 600 Watts of electrical energy into heat and that the auxiliary heating element iticonsumes 200 watts of electrical energy. Movement of the control switch 46 to its No. 1 position effects uniform heat ing of the shoe it as the primary elements 35' and 43 are energized and uniformly impart heat to the shoe throughout its length. At this time, the heating element 55 is also energized so that the heat developed by the 200 watts of energy which it consumes is also uniformly imparted to the shoe throughout its length. As described hereinafter, the heating element $5 is energized in all

active positions

1, 2 and 3 of the switch 5%.

In the first position of the switch 45, the fingers so, 5!, 52 and 53 are bridged by the segment 5:3. Accordingly, one terminal of each of the elements 4!, 3 and E5 is electrically connected by the conductor L2 and the opposite terminals of these elements ii, 43 and 35 are tied together by a conductor E2 which is directly connected to the line conductor L1. As these circuits may be readily traced by reference to Fig. 4 of the drawing, it is not deemed necessary to trace them in detail in this specification.

Assuming the operator desires to use only that portion of the roll adjacent the heating structure H! for ironing small pieces, the control switch 56 is actuated to its No. 2 position wherein the majority of the heat generated by the elements is imparted to the end of the shoe to be used. In the No. 2 position of the switch 46, the

fingers

41 and 48 are bridged by the segment 55 and the fingers 50, 52 and 53 are bridged by the electrically-connected segments 56 and 51. Accordingly, the heating elements 43 and i iat the unused end of the shoe are deenergized as the circuit through these elements is broken at the contact finger 5!. The circuit through the primary heating element 4! may be traced from the line conductor L2 through the stationary fingers 5!] 52, which are bridged by the segments 56 and 51 to one terminal of the element ll and thence through the common conductor 62 to the conductor L1. The circuit through'the heating element 42 may be traced from the contact finger 59 which is connected to the line conductor L2, as described heretofore, through the element 32 and thence through the fingers Aid and il which are bridged by the segment 5-5, to the conductor L1. The heating element 45 is energized by a circuit extending from the conductor L2 through the bridged fingers 52 and 53 and thence through the element 45 directly to the conductor L1.

In the No. 2 position of the control switch 48, as described, the heating elements ll and 42 translate a total of 1200 watts of electrical energy into heat which is imparted to the end of the shoe being used at the time. The heat generated by the heating element :35 is uniformly applied to the shoe throughout its length. Approximately half of this heat is imparted to the end of the shoe being used, and the other half is imparted to the unused end of the shoe to prevent excessive cooling thereof for purposes described in connection with the prior embodiment.

Movement of the control switch 46 to its No. 3 position effects heating of the shoe l3 as just described, except that the greater amount of electrical energy is expended at the opposite end of the shoe or that portion of the shoe heated by the heating structure i5. In this position, the

elements 43 and M are connected in parallel and dissipate a total of 1200 watts of electrical energy, while the heat generated by the 200 watts consumed by the element 65 is uniformly applied to the shoe It. In the No. 3 position of the control switch, the fingers Si, 52 and 53 are bridged by the movable segment 59 and the fingers i! and 49 are bridged by the electrically-connected segments 58. As the circuits for the various heating elements in this position of the control switch may be traced by observing Fig. 4 of the drawing, they will not be traced in detail in the specification.

It'will be apparent that, as in the prior embodiment, the shoe may be uniformly heated throughout its length or may be nonuniformly heated by applying a substantial portion of the energy available to the end of the shoe which is being used and a smaller portion of the available energy to the unused end. The energy applied to the unused and approximates watts of electrical energy or half the wattage of the element 45, so that excessive cooling of the unused end is precluded. The advantages gained by the described distribution of the heat generated by the elements are substantially the same as the advantages recited for the structure shown in Fig. 3.

While I have shown my invention in several forms, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various other changes and modifications without departing from the spirit thereof, and I desire, therefore, that only such limitations shall be placed thereupon as are specifically set forth in the appended claims.

What I claim is:

1. In an electrically-heated ironing machine for smoothing fabrics and the like and deriving energy from an electric circuit, the wattage of which is limited, the combination of a shoe for engaging the material to be ironed and including spaced first and second heated portions, first and second heating means associated, respectively, with said first and second portions of the shoe and each heating means including a primary heating element, and a secondary heating element, the comparable heating elements of each heating means lgving impedances which are substantially equal, said secondary'heating elements having impedances substantially 61 /2 per cent higher than said primary heating elements, a control mechanism movable to a plurality of positions for controlling energization of said primary and secondary heating elements, said control mechanism including means effective in a first position of the control mechanism for connecting both of the primary heating elements in parallel in said circuit, means efiective in a second position of thecontrol mechanism for con- 7 necting the primary and secondary heating elements of the first heating means in parallel in said circuit and the primary and secondary heating elements of the second heating means in series in said circuit, and means efiective in a r third position of the control mechanism for connecting the primary and secondary heating elements of the second heating means in parallel in said circuit and the primary and secondary heating elements of the first heating means in series in said circuit.

2. The combination as claimed in claim 1 including first and second thermostatically-operated switching means associated, respectively, with the spaced heated portions of the shoe, said thermostatically-operated switching means being opened in response to predetermined high temperatures for deenergizing their respective primary and secondary heating elements.

3. In an electrically-heated ironing machine for smoothing fabrics and the like and deriving energy from an electric circuit, the wattage of which is limited, the combination of a shoe for engaging material to be ironed and including spaced first and second heated portions, first and second heating means associated, respectively, with said first and second portions of the shoe and each heating means including a primary heating element and a secondary heating element, the comparable heating elements of both heating means having substantially equal resistances, said secondary heating elements having resistances substantially 61 per cent higher than said primary heating elements, a control mechanism movable to a plurality of positions for controlling energization of the primary and secondary heating elements, said control mechanism including means effective in a first position of the control mechanism for connecting both of the primary heating elements in parallel in said circuit and means efiective in a second position of the control mechanism for connecting the primary and secondary heating elements of the first heating means in parallel in said circuit and the rimary and secondary heating elements of the second heating means in series in said circuit.

WILLIAM C. BRUCKMAN.

REFERENCES 1TED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,594,158 Else July 2'7, 1926 2,248,676 Jensen July 8, 1941 2,307,833 Ferris Jan. 12, 1943 2,203,236 Randolph, et al June 4, 1940