US1177254A

US1177254A - Electric heater.

Info

Publication number: US1177254A
Application number: US6231315A
Authority: US
Inventors: James Lawrence
Original assignee: STANLEY G RANGER
Current assignee: STANLEY G RANGER
Priority date: 1915-11-19
Filing date: 1915-11-19
Publication date: 1916-03-28
Anticipated expiration: 1933-03-28

Description

.I. LAWRENCE.

\ ELECTRIC HEATER. APPLICATION FILED NOV- 19, 1915;

1,177,254. I f Patented Mai. 28,1916,

2 SHEETS-SHEET l.

ATTOIRNEYSII,

J. LAWRENCE ELECTRIC HEATER.

APPLICATION FILED NOV. 19, 19 15- Patentegl Mar. 28, 1916.

2 SHEETS-SHEET 2- INVENTOR JAMES LAWRENCE, NEW YORK,

very subject of the Kin STATES PATENT OF ICE.

EnEoTEIc HE ATER.

To all whom it may concern:

Be it known'that 1, JAMES LAW ENCE, a

of Great Britain, and-a resident of New ork city, .in the county and State of'NeW York, have invented certain new and useful Improvements in Elec-f tric Heaters, of which the following is a specification.

My invention relates'to electric heaters, andparticularly, to that type of heaters which includes heating units comprisingresistance members carried by a supporting body.

coils. So far as the transference of electrical energy to heat is concerned, this method has proved highly efficient. But heretofo re the device's designedfor utilizing the heat "generated from the resistance coils has been ineflicient. It is well'known that the rate ofheat radiation from a body increases in-greater proportion than the intensity of the temperature of that body, and therefore in my device it is my intention that'the heating elements shall be kept at the highest possible intensity of temperature, even though the elements may thereby be consumed; and in order to overcome the inconvenience due to'the burning out of the elements, I intend that the elements shall be. readily replaceable. A welLknown fault present in the electric heating units of this day is. that a great'amount of heat gener-' ated by the heating elements is' absorbed by the member'which supports the heating ele-' ment. In'my device, therefore, the support for the heating element is made with'a mini mum cubicalcontent, so;that while'it su-ffisistance element, to the body tobe heated, the

plate having the minimum cubical content consistent with practical considerations Specification of Letters Patent;

- heating unit .of this specification,

Another object is to provide simple,

N. Y., ASSIGNOR 'ro s'rANnEY e. RANGER, or NEW YORK,

. Patented Mar. 25;, 1916'. Application filed November 19, 1915. Serial No. 62,313. 5

economical and practical meansfor securing an electrlc heating element to a supporting body to form a heating unit.

Another object is to fprovi' heating-unit" which is complete and includes electrodes for the introduction of electric current and which is adapted to be removmember. 1

Another object is to provide a heating unit comprising a heating element supporting ably operatively positioned in a receivmg do an electric plate having means for draining away from I the heating element'material spilled over the unit.

Another object is to provide a heating unit comprising. a heating element .and a plate forsupporting. the element and provided with means to' secure a circulation of heat generated by the element.

Another object istoprovide a receiving member for an electricalheating unitwhich perature variations.

Another object is to provide a receiving member. for anelectrical heating unit, the

having. electrodes for the in-' .troduction of electricity and the rec'elvlng member having spring contacts for accomis durable and resistant to the effect of temmodat-ing the electrodes of a heating un1t electricity to the unit, said receivd pp y also being provided with means in-g member for protecting the contacts from the heat generated by .the unit 'spilled over the unit. 1,

.Another object"'isto provide, a heatingunit and a receiving member therefor, the .unit and member being formed to and from materia'l provide" m'eansjfor preventing. heat frombei'ng con= Y ducted from the un1t to the receivingmember. Y Another object isto providea'jfsupport for .anelectric heating unit receiving member whereby a. complete electric heater. is pro vided'wh'erein the heating units are read ly interchangeable.

Other and further objects and advantages of my inventionfwill'b'e disclosed in th'e' following descriptiontaken in connect on with the accompanying drawings forming a part in the claims. I I

Inthe drawings, in whichlike reference and will be pointed out ing my invention; Fig. 2 is a partial crosstions of heating unit receivers.

The electric heater which is illustrated by the drawings and described in this speciflcation is one embodiment of my invention and is described for purposes of interpretation thereof. The top plate 1 of the heater, together with the legs 2 attached thereto, comprises a support for the heating unit receiver 3, and the heating unit receiver carries the heating unit plate 4 on which I there are mounted heating elements 5. The

top 1 of the heater has a circular opening therein, andto the top are secured brackets 6 upon which rest the circular receiving member 3, which is slightly smaller than the hole in the top 1, thereby leaving an opening 8 between the top of the support and the receiver 3, so that air may circulate through the opening to prevent the conduction of heat from the receiver to the support. The upper surface of the top 1 is shown by Fig. 2 tobe slightly above the upper surface of the receiver 3, so that heavy articles placed upon the heater may be supported by the strong supporting member rather than by the heating member 4 which is of refractory material. The difi'erence in the level of the upper surfaces of the receiver and the top 1 also permits receptacles which are warped to be placed into close contact with the heating plate 4. The heat ing plate 4, as shown by Figs. '8 and 9, is a circular member having openings 9 and a cross bar 10. The openings may be large as shown in Fig. 8, in which case the rim is provided with slots 11 to relieve strains arising in the circular portion by reason of variation in the temperature ofthe-receiving member. The openings 9 may be small as shown in Fig. 9,:and the receiving member is made in three parts, 3*, 3 and 3, and variations in temperature will not cause its destruction. Within the upper surface it the receiver there is a circular opening,

jacent the wall of this opening there is formed in the receiving member a supportingledge 12, and upon this ledge the heating unit 4' is supportedso that its upper surface is practically flush with the upper surface of the receiver, but it is to be understpod that I do not confine myself to the detailed arrangement .described.

Either upon the ledge or upon the lower face of the plate 4 of the heating element projections 13 are formed which elevate the plate 4 above the ledge. The plate 4 is made smaller than the opening in the receiving cal coils of suitable resistance wire of such,

material and dimensions that it will be heated immediately to incandescence without a great initial rush of current when the current is turned on, and will be kept at a destructive temperature therafter. The plate 4 is of refractory material and so designed that they are readily replaceable because the heating element is operated at a destructive temperature. It is designed to have the minimum cubical content possible without substantial loss'of strength, so that heat of the heating element will not be taken from the article to be heated when current is first turned on, or stored up to be wasted after the current is turned off. The opening atthe top of the grooves is entirely unobstructed and it will be seen from the shape of the grooves that the radiation from the heating element will be the freest possible to obtain, and that absorption of heat by the sides of the groove will be almost negligible.

The ends of the heating element near the edges ofthe plate are passed through openings in the plate, as are also the ends of the elements at the center. To the back of the plate at the edges and at the center, as clearly seen in Fig. 2, there are secured electrodes 15 which extend down through holes 16 in the cross bar 10 of the receiving member 3. Secured to'the lower face of the receiving member, by bolts 18, there are contact supporting bars 17. On each of these contact supporting bars there is mounted a spring clip 19 which, asshown in Fig. 2-, accommodates one of the electrodes 15 when the heating'unit is dropped into the opening in the receiving member. Binding posts 20 from any material which may pass through the drain holes 32 a plurality of which extend through the plate 4 from the bottom of the groove therein.

In the upper surface of the receiving member there are formed grooves 21 so that the heating unit,plate 4 may be grasped by the fingers to remove it. In the upper face of the heating unit plate there are provided radial grooves 22 which intersect the grooves in which the heating elements are positioned. This is to permit circulation of heat across the face of the heating element when only one of the two concentric spirals of the heating elements is radiant.

It is old to retain the heating element in its groove by forming projections extending from the top edge of the walls of the groove out over the heating element. These projections I have done away with, in order that all of the heat may radiate directly to the article to beheated, and I have shown several methods of anchoring the heating element within its groove. In Fig. 3 I have shown a preferred form of heating element anchor. The heating element is formed with long loops of wire 24 which pass through openings 25 through the plate in the bottom of the groove. The long loop 24 is then spread out into the wide loop 26 and subsequently flattened into the knot of wire 27 shown at the right of Fig. 3. By anchoring the heating unit in this way a negligible portion ,of the heating unit. is covered by the plate andat the same time a very simple and efficient anchoring means is provided. In Fig. l I have shown an anchoring means which consists in a loop of wire passed through one hole in the plate over one loop of the heating element and back through another hole in the plateand knotted to prevent loosening. In Fig. 5. I have shown a loop of wire passing through a single hole in the plate and inclosing a loop of the heating element and being knotted to prevent its being pulled through the plate by any strain on the heating element.

While it is old to have a heating element of the type which I employ positioned in a straight groove, the top opening of which is unobstructed, it will be seen that I have devised a heating unit which includes a plate having a curved groove the top opening of which is unobstructed and the heating element, which is positioned in the groove, is held from straightening out and positioning the scope of my invention which I desire to be defined only by the hereunto appended claims.

Having thus described my invention, what .I claim as new and desire to secure by Letters Patent, is

1. As an article of manufacture, a heating itself above the top of the groove by 1 ,a nchors which hold it. against the bottom of heating elements,

2. As an article of manufacture, a heating unit comprising a plate having a continuous groove in one face thereof and recesses'in the other face thereof and openings extend ing from the bottom of said groove through said plate and into said recesses, and a heating 4 element positioned in said groove, said ele- 'ment havingloops extending through said openings and being shaped to cooperate with the opposite face of said plate Within said recesses to anchor said element to said plate at intervals throughout the extent of said element.

3. In a device of the class described, a heating unit having electrodes for the introduction of electricity thereto, a receiving member for said unit, spring supply contact members for cotiperating with said electrodes to deliver current thereto, and means carried by said receiving member to protect said contacts from the heat generated by said unit.' I

4. Ina device of the class described, a heating unit comprising a body member of insulating material and a heating-unit-supporting receiving member having a recess into which said body member fits and comprising a ring and a cross-bar, said ring being split to avoid strains due to temperature variatlon.

5. In a device of the class described, a heating unit comprising a body member of insulating material and a heating-unit-supporting receiving member of refractory ma- I 'terial comprising separated segments of a ring and a member oining said segments,

the inner surface of said ring being shouldered to permit said unit to rest within said receiving member.

6. In a device of the class described, a heating unit comprising a plate having a' plurality of grooves in one face thereof, and

respectively positioned in said grooves, said plate having additional grooveshaving a cross-section substantially equal to that of said first named grooves; respectively connecting portions of said firstnamed grooves, whereby heat uniformly when a body rests on said plate.

7. In a device of the class described, a heating unit comprising a plate having concentric spiral grooves in one face thereof, and heating elements extending .throughout said grooves, said plate having radial grooves having a cross-section substantially may circulate insulating material, a receiving member therefor comprising a ring having a shoulder portion formed on its inner surface to support said plate at its edges, one of said portions being provided with projections for separating said portions to permit air circulation.

9. In an electric stove, the combination of a removable and replaceable heating unit support, a heating unit comprising a heating element of such construction and resistance as to be raised to incandescence substantially immediately upon the passage of a current.

of the voltage for which it is designed, said heating unit being so positioned upon its support as to permit of the ready removal of such heating unit and its replacement by another similar heating unit, and electrical conducting surfaces on the heating unit support and said unit so arranged as to contact with one another and close electrical connection at such points upon the mere placing of the unit in its place in the support, whereby electrical heating units may be used capable' of being brought to a high degree of heat at once upon the passage of current and that whenburned out such heating units may be readily removed and replaced.

10. In a device of theclass described, a heating unit having electrodes for supplying current thereto, a supporting member for said unit andhaving perforations through which said electrodes extend, and spring supply contacts with which said electrodes cooperate after passing through said supporting member.

11. In a device of the class described, a heating unit having electrodes for supplying current thereto, a cross-bar passingbeneath said unit and having recesses in its lower r face, and openings through said bar into said recesses, spring supply contacts in said recesses, said electrodes being adapted to extend through said openings to cooperate with said contacts.-

12. In an electric heater, a stand comprising 'a top plate and supporting means therefor, said plate having an opening therein, a receiving member of insulating material supported by said stand within said opening and spaced from the edge thereof, and an electric heating unit carried by said receiving member and removable therefrom.

.In testimony whereof, I have signed my name to this specification.

JAMES LAWRENCE.