US 3489866 A
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Jan. 13, 1970 B. J. TAMARIN 3,489,866
ELECTRICAL CORD REEL Original Filed May 6, 1965 2 Sheets-Sheet 1 l7 w I vii,
IN V EN TOR.
BE RNA RD J. TA MA R/N.
IS ATTOR EY.
Jan. 13, 1970 B. J. TAMARIN ELECTRICAL CORD REEL 2 Sheets-Sheet 2 Original Filed May 6, 1965 g INVENTOR. BERNARD J. TAMAR/N, W W H/s ATTORNEY United States Patent 3,489,866 ELECTRICAL CORD REEL Bernard J. Tamarin, Philadelphia, Pa., assignor to The Vacuum Cleaner Corporation of America, Philadelphia, Pa., a corporation of Pennsylvania Continuation of application Ser. No. 453,787, May 6, 1965. This application July 11, 1968, Ser. No. 747,024 Int. Cl. H02g 11/00; F16j 15/34; F16i 15/54 US. Cl. 19112.2 8 Claims ABSTRACT OF THE DISCLOSURE In an electric cord-reel, a thin circular dust-barrier disc formed of a form-retaining though transversely resilient insulating sheet material, such as a thin fiber-board, impregnated fiber sheet or plastic sheet, stationarily mounted to the stationary brush-block of the electrical cord-reel and to the electrical contact-brushes carried thereby, said dust-barrier disc having its inner portion supported by said brush-block and having an outer portion thereof extending radially outwardly from its inner blocksupported portion and being unsupported in an axial direction except by the inner block-supported portion of the disc and being resiliently flexible in an axial direction in relation to such inner portion of the disc and having an annular peripheral portion bearing resiliently against the face of the juxtaposed cord-retaining flange of the rotary cord-take-up adjacent the collector-ring chamber in the hub of the cord-take-up.
This application is a continuation of my copending application .Ser. No. 453,787, now abandoned.
The present invention relates to electric cord-reels generally of the type exemplified by the electric cord-reels of US. Patents 2,391,840, 2,443,701 and 2,521,178, and has for its object the better maintenance of good electrical contact between the electrical brushes and the electric collector-rings, without any attention thereto by the user, and the prevention of the accidental intrusion of foreign objects into the zone of said rings and brushes, and to shield the electric collector-rings and brushes from metal and carbon dust which may cause an electrical shorting or leakage, and also to shield same from non-conductive dust which may impair the electrical contact between the collector-rings and brushes.
In electrical cord-reels the contact between the electrical brushes and the electrical collector-rings tends to deteriorate in time due to dust gathering on such collector-rings and brushes, which dust tends to interfere with the electrical contact therebetween, and also tends to create wear. Dust particles also tend to absorb and render less effective the film of lubricant which is applied to the collector-rings in the course of the manufacture of the cord-reel, thus further tending to render the electrical collector-rings and brushes less effective in the course of time. If on the other hand the dust is of metal or carbon, then in time the danger of an electrical shorting or leakage develops.
One of the objects of the present invention is a simple and inexpensive dust-guard construction in electric cordreels, which permits more ready and quick assembly in relation to the electrical brushes and the brush-mounting insulator-block, and which will be effective without deterioration over long periods of time.
The further object of the present invention is a generally simplified, less expensive and yet eflective cordreel construction and the mounting thereof.
The above and other objects will appear more fully from the following description and the accompanying drawings, in which like reference characters indicate like parts.
3,489,866 Patented Jan. 13, 1970 FIGURE 1 represents a front perspective view of a cord-reel exemplifying an embodiment of the present invention.
FIGURE 2 represents a rear elevational view of the same.
FIGURE 3 represents an elevational view of a cordreel embodying the present invention, partly in section on lines 33 of FIGURES l and 2.
FIGURE 4 represents a view of the collector-rings and the disc-like insulating member in and to which they are mounted-viewed normal to the plane of said rings and of said insulating disc (the spacial relationship of the brushes and of the dust-guard disc being indicated in dotted lines).
FIGURE 5 represents a similar View of the electrical brushes and the dust-stop or dust-guard disc to which they are mounted-viewed generally on line 5-5 of FIGURE 7.
FIGURE 6 represents an elevational view, on line 66 of FIGURE 7, of the outer face of the brush-mounting block and the dust-guard disc.
FIGURE 7 represents a section on line 7,.7 of FIG- URE 6, on an enlarged scale.
FIGURE 8 represents a fragmentary view of a detail of the invention.
In the embodiment of the present invention shown in the drawings, the electric cord-reel includes two arbor supporting band-like or strap-like sheet-metal members or plates 11 and 12, between which the opposite ends of the stationary arbor 13 are secured by means of the screws of 14 and 15 which are threaded into threaded axial holes in the ends of the arbor-the end of the arbor mounted to the plate 11 having a flat thereon and the plate 11 having a corresponding elongated hole therein in which such flat nests, so as keyingly to interlock the arbor 13 and the strap 11, to prevent the arbor from rotating in relation to the strap 11.
The strap 12 has a pair of opposite portions 16 bent at a right angle to the main body of the strap 12, and the portions 16 flank the reel at diametrically opposite portions thereof, as shown particularly in FIGURES 1 and 3. From each of the reel-flanking portions 16, a securing-tab 17 is bent outwardly as indicated in FIG- URES 1 and 3, and each of the securing-tabs 17 is provided with a hole 18. The band strap 11 is provided with offset securing tab portions 19, and these tabs are provided with holes 20 flanked by a slight tubular projection 21 drawn from the tabs 19 (around the holes 20) and these tubular projections 21 nest in the holes 18 in the mounting tabs 17, thereby to dowel the mounting-tabs 17 and the mounting-tabs 19 to each other.
The cord-storing reel designated generally by the numeral 22 includes a dished spring-housing member 23 in which the cord-retrieving or cord-winding spring 24 is operatively mounted, with its outer end anchored to said dished spring-housing member and with its inner end anchored to the arbor 13. The cord-storing reel 22 further includes a dished insulator-receiving member 25 secured to the dished spring-housing member 23 and having a cord-retaining flange 26. The cord-storing reel 22 further includes a spring-enclosing and cord-retaining disc 27 secured to the open side of the dished springhousing member 23 in the manner indicated in FIG- URES 2 and 3.
A dished latch-housing 28 is secured to the disc 27, and within said housing 28 any suitable reel locking and releasing mechanism may be provided for retaining the reel 22 against cord-retrieving rotation by the spring 24 and optionally to release said cord-reel 22 so as to per' mit the spring 24 to retrieve the cord thereon. Details of such locking and releasing mechanism are not shown because same may be any conventional reel locking and 3 releasing mechanism, as, for instance, the mechanisms shown in US. Patents 2,391,840 and 2,521,178.
The electrical cord 29 is disposed on the cord-reel 22 in the manner indicated in FIGURES 1 and 3 and is paid out tangentially through any suitable cord-pay-out member 30 mounted in or to the housing of the appliance in which the cord-reel is installed, with the axis of the hole 31 thereof generally tangent to the reel. An antifriction bushing, grommet or eyelet (not shown) may be provided in the hole 31.
The inner end of the cord 29 extends radially inwardly through the hub-portion of the dished member 25 and then into the round insulating-block 32 mounted to or nested in the dished member 25, where th individual wires thereof are soldered to the collector-rings 33 and 34 in any conventional manner (not shown).
A brush-carrying block 35, formed of insulating material (such as a molded plastic), is shown in FIGURE 7 on a scale approximately twice that of FIGURES 3, 5 and 6. The brush-block 35 includes a central opening 36 through which the cylindrical terminal portion 37 of the arbor 13 extends-the hole 36 of the brush-block 35 being centered by the arbor-end 37 nested therein. Rivetholes 38 and 39 extend through the block 35, spaced from the axis of the hole 36 at the respective radial distances of the collector-rings 32 and 33, as indicated in FIG- URES 4 and 7.
The brush-block 35 also includes grooves 40 and 41, recessed into the outer face thereof, in which grooves the stationary electrical leads 42 and 43 are adapted to nest, as indicated in FIGURE 6.
A hole 44 extends from the rivethole 38 through the end of the brush-block 35 and another hole 45 extends from the end of the brush-block into the groove 40, so that the electrical lead 42 may first pass from the rivet in the hole 38 outwardly and then back into the groove 40. Similar holes 46 and 47 are provided at the other end of the brush-block 35 for the like passage of the electrical lead 43 from the rivet in the hole 39 into the groove 41.
The two-pronged electric-contact brushes 48 and 49 are made of flat spring bronze or like spring-metal and have square rivet-receiving holes therethrough in the central portions thereof with small outwardly turned keying tabs but from two sides of each square hole in the center of each brush and extending into the square rivet holes in the brush-block 35, so as to prevent the brushes from turning in relation to the brush-block. The hollow tubular rivets 50 and 51 extend through the said rivetholes in the brushes and through the rivet-holes 38 and 39 in the brush-block and are riveted over to secure the brushes to the block.
To the opposite ends of each of the brushes 48 and 49, silver or similar contact-members 52 are mounted for more effective electrical sweep-contact with the collector-rings 33 and 34.
The ends of the metallic conductor-wires within the leads 42 and 43 are extended through the hollow tubular rivets 50 and 51 and are soldered therein.
Between the riveted central portions of the brushes 48 and 49 and the juxtaposed inner fac of the brush-block 35, a dust-stop or dust-guard disc 53 is operatively disposed, as indicated in FIGURES l, 3, 5, 6 and 7said disc being formed of a form-retaining though slightly resilient insulating material (such as thin fiber-board, impregnated fiberor plastic).
Disc 53 has a central opening 54 therein to clear the arbor-end 37 and corresponding generally to the arborhole 36 in the brush-block 35. The outer periphery 55 of the disc 53 bears resiliently against the slightly concave face 56 of the cord-retaining flange 26, with just sufficient pressure to form a dust-seal, but not with sufiicient force to impose any significant braking action on the reel 22.
A keying knob 57 is provided on the outer face of the brush-block 35. The knob 57 passes through or nests in a corresponding hole 58 in the flat arbor-supporting straplike member 12 and thus prevents the brush-block 35 from rotating.
The stationary electrical leads 42 and 43 pass through perforated and grommeted bosses 59 in the flat band 12, and may have attached to their ends any suitable electrical plug (not shown), or said leads 42 and 43 may be directly connected to corresponding electrical terminals on the appliance to be served by the electrical cord-reel.
By means of the disc 53, the electrical contact-rings 33 and 34 and the brushes 48 and 49 are sealed off from the, exterior, in a manner which substantially prevents the ingress of dust into the zone of said rings and brushes, thus preserving their electrical efiectiveness against deterioration due to dust.
The disc 53 also serves as an electrically insulating guard to prevent accidental contact with the collectorrings and brushes by any foreign object, such as a screwdriver, nail or stray piece of wire.
.Pairs of stifiening webs 60 are formed between the portions 16 and the securing-tabs 17 of the arbor-sup porting band or plate 12.
The completed reel may be mounted to any suitable wall of the appliance which the cord-reels serve, by screws or other fastening means extending through the holes 20.
If the reel locking-and-releasing mechanism (within the housing 28) is of the gravity type, then the reel should be mounted in a vertical position as indicated in FIGURE 3. If, however, the reel locking-and-releasing mechanism is of the type shown in FIGURES 2, 3 and 4 of Patent 2,391,840 and in FIGURES 4 and 5 of Patent 2,521,178 then the cord-reel may be mounted to a horizontal or inclined surface (as well as to a horizontal surface).
Insulating discs 61 of compressed fiber sheet material or the like, preferably coated with a suitable wax or an analogous material, are press-fitted into the round enlarged chambers 62 in the insulator-block 35, to provide an insulating closure for the outer ends of the rivets 50 and 51 and the electrical conductors soldered thereto, as indicated particularly in FIGURES 6 and 7. By applying a slight amount of heat to the discs 61 as they are pressfitted into the chambers 62, the wax is momentarily melted and then resolidified, so as to adhere to the interior surface of the chambers 62.
Having shown and described an embodiment of my invention, I claim the following:
1. In an electrical cord-reel including a spring-retracted rotary cord-take-up having a cord-Winding hub, a pair of spaced-apart cord retaining flanges extending radially outwardly from the hub, a collector-ring chamber in one end of the hub, extending axially inwardly from the cordretaining flange at such end of the hub and having two electrical collector rings operatively mounted therein, a dielectric brush-block stationarily mounted in relation to the cord-take-up and in operative juxtaposition to said collector rings and electrical brushes carried by said brushblock in operative juxtaposition to said collector rings, a thin form-retaining though transversely resilient insulating dust-barrier disc having its generally central inner portion stationarily mounted to and between said brushblock and said electrical brushes, fastening means securing said electrical brushes and said brush-block to each other and stationarily clamping the generally central portion of said dust-barrier disc between said electrical brushes and said brush-block, said dust-barrier disc having an outermost annular portion thereof extending radially outwardly from its inner block-supported portion and being unsupported in an axial direction except by said generally central clamped portion of the disc and being resiliently flexible in an axial direction in relation to such inner portion of the disc; such unsupported outer annular portion of the disc bearing resiliently against an annular portion of the face of the juxtaposed cord-retain ing flange of the rotary cord-take-up spaced radially 0utwardly from the collector-ring chamber in the hub thereof, whereby said resilient dust-barrier disc may compensate for wear in the contact between the disc and the flange.
2. In an electrical cord-reel including a spring-retracted rotary cord-take-up having a cord-winding hub, a pair of spaced-apart cord-retaining flanges extending radially outwardly from the hub, a collector-ring chamber in one end of the hub, extending axially inwardly from the cordretaining flange at such end of the hub and having two electrical collector-rings operatively mounted therein, a dielectric brush-block stationarily mounted in relation to the cord-take-up and in operative juxtaposition to said collector-rings and electrical brushes carried by and atfixed to said brush-block in operative juxtaposition to said collector-rings, a thin form-retaining though transversely resilient insulating dust-barrier disc having its generally central inner portion operatively mounted to said brushblock and stationarily held in place by said brush-block and extending radially outwardly from said brush-block and brushes into operative juxtaposition to saidcollectorring chamber and forming a cover over said chamber, said disc being so disposed that the collector-rings and brushes are enclosed by said disc, said dust-barrier having an outermost annular portion thereof extending radially outwardly from its inner block-mounted portion and being unsupported in an axial direction except by said generally central block-mounted portion of the disc and being resiliently flexible in an axial direction in relation to such inner portion of the disc; such unsupported outer annular portion of the disc bearing resiliently against an annular portion of the face of the juxtaposed cord-retaining flange of the rotary cord-take-up spaced radially outwardly from the collector-ring chamber in the hub thereof, whereby said resilient dust-barrier disc may compensate for wear in the contact between the disc and the flange, said disc shielding said collectorrings and brushes.
3. In an electrical rotary cord-reel including a cordwinding hub and a pair of cord-confining flanges extending radially outwardly therefrom, electrical collector rings operatively mounted in said hub adjacent one of said flanges, a dielectric brush-block having electrical brushes secured thereto and stationarily mounted in operative juxtaposition to said rings; a thin form-retaining though transversely resilient insulating dust-barrier disc, means mounting the generally central portion of said disc to said brush-block with said brushes exposed on one side of said disc, said disc including an unsupported annular portion extending radially beyond said disc-mounting means which is flexible in an axial direction and bears resiliently and slidably against an annular portion of the confronting face of said one flange with suflicient pressure to form a dust seal but insufficient to impose a significant braking action on the reel.
4. The combination of claim 3 wherein said one flange is slightly concave.
5. The combination of claim 3 wherein said discmounting means also secures said electrical brushes to said brush-block.
6. The combination of claim 3 wherein said disc is made of plastic.
7. The combination of claim 3 wherein said disc is made of fiber-board.
8. In an electrical rotary cord-reel including a cordwinding hub and at least one cord-confining flange extending radially outwardly therefrom, electrical collector rings mounted in said hub, a dielectric member having electrical brushes secured thereto in stationary operative juxtaposition to said rings, a thin form-retaining though transversely resilient insulating plastic dust-barrier disc, means non-rotatably supporting said disc at its generally central portion on said dielectric member without obstructing contact between said brushes and rings, said disc including an unsupported annular portion extending radially beyond its central supported portion and which is flexible in an axial direction and bears resiliently and slidably against an annular portion of said flange.
References Cited UNITED STATES PATENTS 2,443,701 6/ 1948 Tamarin l9l12.2 3,167,161 1/1965 Appleton l9l12.2 2,750,215 6/ 1956 Bermingham 277 DRAYTON E. HOFFMAN, Primary Examiner G. H. LIBMAN, Assistant Examiner US. Cl. X.R. 277-