US1479494A - Combined electric fan and heater - Google Patents

Description

Jan. 1, 1924 M. BECK COMBINED ELECTRIC FAN AND HEATER Filed c. 10. 1920 S'SheetS-Sheet 1 M. BECK COMBINED ELECTRIC FAN AND HEATER Jan. 1,1924 I Filed Dec. 10 1920 3 Sheets-Sheet 5 Patented Jan. 1, 1924.

UNITED STATES PATENT OFFICE.

IICHAEL BECK; OF MINNEAZBOLIS, MINNESOTA.

COMBINED ELECTRIC FAN AND HEATER.

Application filed December 10, 1920. Serial 1T0. 429,770.

My invention provides a highly ellicient combined electrical fan and heater, in which I:

certain of the electrical heating elements are ll carried by the fan blades. Generally stated,

the invention consists of thenovel devices and combinations of deviceshereinafter described and defined in the claims.

, Electrical heaters now generally in use employ stationary reflectors in connection with a heating coil and the projection of the heat rays is produced chiefly by reflection, but, in part, by direct radiation. The efficiency of the heater will depend largely on the amount of air per unit of time passed over or in contact with the heating coil or element.

in accordance with my invention, I obtain extremely high eiliciency by combining heat reflectors and heating coils with the blades of a motor-driven fan. In this way, the heating elements carried by the fan are constantly swept through the air and, moreover, there is a constant reflection of the heat rays from the blades by means of the reflectors carried by or with the blades. F or extremely high efiiciency, a stationary electrical heater is also closely associated with the fan.

The invention is illustrated in the accompanying drawings, wherein like characters indicate like parts throughout the several views.

Referring to the drawings:

Fig. 1 is a front elevation of the combined fan and heater, some parts being removed and some parts being broken away;

Fig. 2 is an end elevation of one of the fan blades, one of the heat reflectors and one of the heating elements, which parts are connected as a slngle element;

Fig. 3 shows the combined fan and heater partly in side elevation and partly in verti-*-- cal axial section;

F 1g. 4 is a fragmentary detail view in. section taken axially through the armature v shaft;

Fig. 5 is a front elevation of the electrical switch shown in Fig. 4 and certain other views;

Fig. 6 is a fragmentary view of a coil of one of the heating elements;

Fig. 7 is a front elevation showing a heating element for application. to a fan blade but which is of a somewhat different type than that, shown in Figs. 1 and 3;

Fig. 8 is a section on the line 8-8 of Fig. 7 and Fig. 9 is a section on the line 9-9 of Fig. 7.

A suitable standard or pedestal 10 mp ports the outer casing 11 ot a small electric is rigidly clamped against a shoulder on the reduced end 14* of the armature shaft. This fan is preferably arranged to work within a protecting cage, which, as shown, is made up of a large ring 17, a small ring 17*, wires 17", that connect the rings 17 and 17 and supporting arms 1'" that directly support the large rin 17 from the motor casing 11 and thus indirectly support the entire cage. Each fan blade 15 is provided with a seg mental heat-deflecting plate 18, preferably of copper, and also with a co-operating electrical heating element. This electrical heating element may take various other forms, but, as shown in Figs. 1 and 3, it comprises a segmental insulating core 19 and a surrounding coil or winding 21. The blade, refiector and core just noted are spaced apart by suitable spacing washers and are rigidly ill Ell

connected together by nut-equipped bolts 20, (see particularly Fig. 3). 'By reference to Fig. 2, it will be noted that the fan blades 15 and preferably also the reflecting plates or reflectors 18, at their rear edges, are curved so that, under rotation of the fan, they produce a forward air-propelling action. Also, the reflecting plates and the cores l9 are'set obliquely to the plane of rotation so that they cooperate in producing this air-propellin action. 7

ln the preierre arrangement of the wires of the heating elements 21, an iron and a copper wire are twisted together in contact and connecmd in circuit as a single conductor. ln such an arrangement, the copper wire will respond more quickly than. the iron wire to the heating chest of the current and the iron wire acts. as a supplemental or oscillatory conductor adapting the element to withstand quite high voltage and end of the reduced end ll of the tubular Elli to carry a very large amount of current.

The inner terminals of the heating coils 21 are adapted to he connected, at will, by a switch bar 22 carried by a turn key 23, which, as shown, is swiveled to a plug in the armature shalt 12. As shown, these inner terminals of the two heating coils 21 are connected to diametrically opposite contacts 2i carried by an insulating ring 2d that is securedto the extreme end ll of the armature shalt: The other terminals 21",

mutator thereof.

of the two coils 21, are connected to diametrically dpposite sections of the commutator 13, (see Fig. 4),being extended outward through the tubular section in of the armature shaft and thence radially outward through diametrically opposite perforations therein. With this arrangement, the heat elements on the tan will be supplied with current from the motor through the com-' The stationary electrical heater, as shown, is made up of a multiplicity oi radially disposed coils 25 that are extended inward from the cage '17 and, at their inner ends, are anchored to a small inner ring 26. I The several walls 25 are preferably connected in series and may be supplied with current from any suitable source and controlled by any suitable switch, but preferably by a switch that is operative independently of the switch that controls the supply of current to the heating elements on the fan. Such a switch, is indicated in part by the numeral 27, the same being applied in the base oil the standard l0. ln the arrangement above described, it is necessary that the rings l? and 26 be of insulating material or covered with insulating material, so as to thereby prevent short circuiting of the coils 25.

The ,eliiciency oi the combined tan and I heater is thought to be obvious. When both types oil heating elements described, towit":

ments may be out out of action. As is evident, the tan will draw air rapidly through the fixed heating coils 25, thereby bringing a large amount of air rapidly in contact with said coils. 'lhe coils or heating elements on the tan will be swept through the airhigh velocity and the air will be projectediroin the fan blades athigh speed, thereby heating a very large amount oi air within any unit of time.

lln Fig. i, only a small number oil radial coils are shown. The positions of other coils are indicated by broken lines marked 25.

Figs. 7, 8 and 9 show a modified iorrn oi heating element'lor application to the fan blades. ln this construction, the heating coil 28 is wound around a segmental insulating core 29 or mica or the like. and coil are enclosed in a llat thinsheet metal casing 30, which, as shown, is, one a cc This core l. The combination with a motor-driven fan, of a heat-reflecting and an electrical heating element applied to a blade-thereof. J

2. The combination with a tan having a plurality of blades, of electrical heating ele-- ments applied to the fan blades, and an axial switch tor making and breaking the circuit between the heatin elements of said blades.

3. The combination with a motor-driven a. The combination a-motor-driven fan, of heat reflectors secured. to and spaced from the fan blades, and electrical heating elements secured to and spaced from said reflectors, the rear edges of the tan blades and of said reflectors heing'laterally bent to produce an air-propellingaction. v

5. The combination with a motordriven radr electrical heating-elements carried by the rotary element of the tan, and independent circuit connections whereby said mov able and stationary heating elements may be independently thrown into and out of action. 6. The combination with a motor-driven tan having radial segmental blades, of radial segmental electrical heating elements applied to' said tan blades on the air delivery side thereot. 4

7. The combination with a motor-driven tan, of an electrical heatin element applied llll lZll

Mill

prising a conductor made of two wires of 9. The structure defined in claim 8 in furdifierent metal twisted together or closely ther combination with a stationary electrical 10 associated and connected as a single conheating element located immediately back of ductor. the fan.

I 8. The combination with a motor-driven In testimony whereof I afiix my signafan, one blade of which affords a casing, and tuna. an electrical heating element carried 1n the casing. MICHAEL BECK.

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