Drier

July 16, 1935.

A. C. McCORD

DRIER

Filed Feb. 26, 1934

2,008,183

Sheets-Sheet 1

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July 16, 1935.

2,00

A. C. McCORD

DRIER

Filed Feb. 26, 1934

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. 2 Sheets-Sheet 2

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Patented July 16, 1935

2,008,183

UNITED STATES PATENT OFFICE

2,008,183

DRIER

Alvin C. McCord, Detroit, Mich.

Application February 26, 1934, Serial No. 712,897

Claims.

(This invention relates to electrically operated driers of the type which discharge a blast of heated air for hand, face, hair, apparel and other drying purposes.

® An- objection to devices of this character as heretofore used is that a blast of relatively cold air is frequently discharged from the drier on starting it, especially when there is an appreciable lapse of time between starting operations. 10 This is due to the fact that these driers operate at full speed and at full air supply at all times, and the heating element provided in the drier for heating the air requires an appreciable length of time on starting the drier to raise the tem15 perature of the high velocity air to that required for drying purposes. In other words, the conditions are such that the heating element is delayed in reaching its full heating capacity and the hot blast desired for rapid drying is ap20 preciably delayed, slowing up the drying operation as is apparent.

In accordance with my invention, I overcome these objections by so controlling or regulating the amount or the volume of the air admitted 25 to the blower or other air flow producing means of the drier on starting it that an opportunity is afforded for the heating means to rapidly reach its full heating capacity and provide for an almost immediate rise in temperature of the dis30 charged air. This occurs early in the starting operation and the hot blast required for rapid drying is discharged from the drier almost Immediately on starting it or within an appreciably short time thereafter and continued in the 35 continued operation of the drier.

The air controlling means, in accordance with my invention, is time controlled, whereby the heating means is brought up to full heating capac₄₀ ity within the required number of seconds after the drier has been started. This provides for a rapid increase of heat within a predetermined period of time and obtains an almost immediate rise in temperature of the discharged air.

controlling means of my invention may be in the form of a valve for the air intake opening of the blower or other air flow producing means of the drier, the valve normally closing said opening when the drier is started whereby 50 the heating means will be required to first heat only the air contained in the drier.

The timing means in accordance with my invention controls or so retards the opening of the „ ^{that the}. ^heating means by the regulation 55 of the air flow in the drier is brought up to its full (Cl. 219—39) heating capacity by the time the valve is fullv open.

It is a further object of my invention to have the opening of a valve induced by the pressure of the incoming air drawn against the valve by the olower or its equivalent in the drier construction and to also have the operation of the timing means controlled through the movement of the va.ve, whereby these devices may function automatically and be set in operation on starting the drier.

A further object of my invention is to have the timing mechanism in the form of a governor controlled speed reducer whereby the opening movement of the valve will be gradual, and consume just the period of time required for the heating means to reach its full heating capacity by the time the valve is fully open and thus obtain a hot blast almost immediately the drier is started or within a very short time thereafter.

±he invention consists further in the matters neremaiter shown, and described.

In the accompanying drawings:—

Fig. 1 is an end view with parts broken away and in section, respectively, of a drier embodying the features of my invention;

Fig. 2 is a longitudinal sectional view with parts in elevation taken on line 2—2 of Fig. 1;

Fig. 3 is a horizontal view taken on line 3—3 of Fig. 1; _and

Fig 4 shows the starting switch for the drier and the actuator for the switch, the showing being more or less diagrammatic.

As shown in the drawings, the blower or air flow producing means is of the centrifugal type. 35 I. has an outer casing I and bladed air impeller oi .an 2. The latter is eccentrically mounted in tne casing and draws air into the same through an opening 3 in one of the side walls of the casing and in concentric relation with the axis 40 of the fan. xhe latter discharges air from the casing through a discharge nozzle 4 provided on tne front side of the casing and extending outwardly therefrom in transverse relation to the axis of the fan, as shown in Fig. 1. The outer 45 end of the nozzle may be covered by a protective ocieen 5 An electric motor 6 operates the fan. The motor is located on the side of the blower casing opposite its air intake opening and has its armature shaft 7 extending into the blower «0 casing and directly connected with the fan 2 as shown in Fig. 2.

_tn^AJ^leey® ^{OT cylindricaI} member 8 is connected to the blower casing about its opening 3 and extends laterally outward therefrom as shown in « .,183 broken lines a in Fig. 2. With the disc fixed to the rod 23, the latter will turn with the disc in its opening and closing movements.

To retard the opening movement of the disc 22, I provide a timing mechanism. The latter 5 is mounted on the plate or head 2 i of the machine at the side of the blower containing the sleeve 8. This mechanism comprises a pair of laterally spaced upright standards 25, 25 secured to the base 2i and providing a mounting for a speed 10 reducing gear train of the type usually employed in clock work. This gear train includes an arm 26 secured to the shaft 27 for the larger of the gears 28. The arm 26 has a laterally extending pin 29 connected with a crank 30 at one end of 15 the rod 23 by a link Si. The pin 29 extends beneath the arm 32 of a bell crank lever S3 fulcrumed at 34 between or on one of the standards 25. The lever is so arranged that the arm 32 is substantially horizontal when the valve disc 22 20 is closed, at which time current to the motor and heating element of the drier is turned, off. The other arm 85 of the lever 33 extends downwardly from its fulcrum and is connected at its lower end with a coil spring 30 which is secured 25 at its opposite end to a fixed support 37 on . the base of the machine. The spring 36 serves to return and normally maintain the lever -33 with its arm 32 horizontal as shown in Fig. 1.

Below the lever- arm 32 is an arm 38 rigidly 30 secured to the upper end portion of the rod 20 and extending laterally outward therefrom. The arm 38 moves up and down with the rod 20 in its vertical movement and is pref er ably, attached to the rod below the connection between the rod 35 and the switch lever 19. This connection compresses a pivot pin 39 extending through the rod and the bifurcated end of the lever which end straddles the rod as shown. The connection between the arm 38 and the rod 28 is such that 40_:the arm moves up and down with the rod as an integral part thereof. In the drawings, I have shown the arm 38 embracing the rod and rigidly secured by a pin thereto. When the timing mechanism and the rod 20 are in the offset rela- 45 tion as disclosed in the drawings, the.arm 33 is given the angular form shown in Fig. 3 to reach from the rod 28 to the leyer arm-32. . A guide 40 is provided intermediate the ends of the arm 38 to guide it in its up and down movement with 50 the rod 28. This guide may be; in the form of a pair of laterally spaced upright plates or strips secured to the base 2! and disposed to have the arm slide between them.

The timing mechanism is provided with a gov- 55 ernor device to regulate the speed of its operation. This, governor, as shown in the drawings, comprises a bladed member 41 fixed to the shaft 42 of the terminal pinion 43 of the gear train. In this form the governor is a wind break con- 60 trolling the. speed of rotation of the gear train by the resistance offered by the surrounding air to rotation of its blades.

The device shown and described operates as follows: . 65

In normal position, the valve disc 22 is closed,, that is, it closes the air intake opening to the blower i. When the operator steps on the pedal at the base of the machine, the rod 20 is raised, thereby closing the switch 96 and supplying cur- 70 rent to the motor 6 and the heater SO simultaneously. The motor attains its normal high speed rapidly and rotates the fan at that speed. An amount of air considerably less than, the full supr ply is drawn into the blower by the rapidly rotat- 75

2,006

Fig. 2. A coupling element in the form of a ring or collar 9 is employed for connecting the sleeve to the blower casing. The sleeve 8 increases the length of the air intake passage for the blower 5 and provides a mounting and a support for the electrical heating element and also the air controlling valve of my invention. The air intake opening for the blower is at the outer end of the sleeve.

The heating element comprises a coil i G of electrical resistance wire wrapped around a support 11. This support is of electrical insulating material and is preferably in spider-like form, it has legs 12, 12 located in the sleeve 8 and se15 cured, thereto as by means of screws or bolts 18,.

13. The support 11 extends into the fan or. impeller 8 through the collar 9 as shown. The ends of the wire comprising the coil 10 are connected to terminals 14, 14 secured to the sleeve 8 as 20 illustrated in Figs. 1 and 2. Conductor wires 15, 15’ connect: these terminals with the electric starting switch 16 of the drier device as shown in Fig. 1. This switch is also connected by conductors Π, IT with the terminals of the motor S. 25 The current supply wires 18, 18 are also connected with this switch as shown in Fig. 4 to be later described.

The construction of the switch, 16 is such that it controls the supply of electrical current to the 30; motor, and the heating element, respectively, turning on and off the current to both elements simultaneously on the closing and opening of the switch. To accomplish this result, the switch has an actuator 19 extending outwardly on one 35. side of. its housing, said actuator preferably being in the form of a lever as shown in the drawings. This lever is connected to the upper end of an actuating rod 26. The rod is vertically disposed and extends downwardly from the switch 40· through the top plate or head 21 of a pedestal on which the drier assembly is mounted in the form of device shown in the drawings. The rod 20 is provided at its lower end with an operating, member; preferably in the form of a foot 45· pedal 20α (Fig. 4) at the lower end of the pedestal. When the foot pedal is depressed by the operator using the device, the rod is raised, and the switch 16 is closed to supply current to the. motor 6. and. heating element II, respectively. 50- A coiled spring 20b at the pedal lowers the rod on release of the pedal, thereby opening the switch 16 and cutting off the current to the motor and the heating element.

The valve for the air intake opening of the 55; blower is in the form of a disc 22 mounted in the sleeve 8. on the outer side of the heating element 10. The sleeve is cylindrical and the disc is circular, having a diameter to. fit within the sjeeve and close it when the valve is in closed 60. position as shown in full lines in Figs. 1 and 2. The disc 22 is pivotally mounted in the sleeve by means of a rod 2.3 extending across the face of the disc on one side and journaled at its ends in the wall of the sleeve. The disc may be secured 65 to the rod in any preferred manner. Loop shaped portions 24 are shown for the purpose in the drawings, these loops being pressed out from the disc and snugly fitting about the rod. The rod 23 is located slightly above the. center of the 70. disc 22, whereby the disc is mounted off center in. the.. sleeve. This presents a larger surface area to the incoming air on the lower side of the disc than on the upper side, whereby the air. drawn into the sleeve by the fan will swing 73, the disc into its open -position, as indicated, by tog fan about the periphery of the closed valve disc and through vent openings 44 provided in the portion of the disc above the rod 23. The amount of air entering these openings is controllable by a plate 45 shiftably mounted on the valve disc and having openings 46 to register with the opening 44 in the disc. The plate 45 is pivoted on the disc at its center and has a finger piece 47 whereby the plate may be moved. The finger Piece 47 frictionally engages the valve disc for holding the plate in its positions of adjustment. The openings 44, 46 also relieve the pressure of the incoming air on the upper side of the valve disc whereby the pressure on the lower side will overbalance the disc and swing it to its open position.

The opening of the disc 22 is retarded by the governor 41. When the rod 20 is raised, the arm 32 of the bell crank lever is also raised by the upward movement of the arm 38 against the underside of the arm of the lever. This will release the lever from the pin 29 on the arm 26 of the timingdevice and the valve disc is freed to swing to its open position by the pressure of the incoming air on the lower side of the disc. As the disc swings, it turns the rod 23 and raises the arm 26. This actuates the gear train and rotates the governor or windbreak 41. As the windbreak revolves, its olades by contact with the surrounding air control the speed of rotation of the gear train and the opening movement of the valve disc is retarded for the period of time required for the arm 26 to raise the pin 29 into contact with the underside of the raised lever arm 32 as shown to dotbed lines in Fig. 1. This lapse of time is predetermined, being regulated by the ratio of the gear train and the size of the windbreak blades. The movement is at a substantially uniform rate and the opening movement of the valve disc is gradual. Thus the amount of air admitted to the blower in the initial operation thereof is controlled and the heating element 10, which is turned on with the starting of the blower, is afforded an opportunity to rapidly raise the temperature of the discharged air. This is further enhanced by the fact that the valve disc completely closes the air intake opening when the blower is started, thus requiring the heating element to first heat only the air already contained m the drier, that is, within the chamber formed by the fan housing 1 and the intake sleeve 8 With this arrangement, the heat increases until the valve disc begins to open, and with the amount of air admitted to the blower controlled by the gradual opening of the valve, the heating element is brought up to its full heating capacity by the vime the valve is fully open and so functions to the continued operation of the blower. As this occurs in an appreciably short period of time after starting the blower, in the neighborhood of ten seconds with the timing mechanism shown herein, an almost immediate rise in temperature of the discharged air is secured. This promotes early drying and avoids the delay in bh±s lespect in driers as heretofore used wherein the blower operates at full air supply and maximum speed on starting.

When the valve disc reaches its fully open position as shown in the broken lines in Fig. 2, the arm 26 will have reached the limit of its upward movement, its pin 29 being brought into contact with the underside of the raised lever arm 32 which is held to its raised position by the arm 38 of the operating rod 20. It is understood that the operator of the machine must hold the

2,008,183 3 ! pedal of the machine depressed as long as he l wishes to maintain the drier in operation. When the valve disc fully opens, there is an uninterrupted supply of air to the blower and the hot blast is maintained throughout the continued operation of the drier.

On release of the foot pedal, the rod 20 by reason of the spring 20b is lowered, carrying the member 38 downwardly and allowing the spring 35 to return the lever arm 32 to its normal position against the upper side of the lowered arm 38. The downward movement of the lever arm under the action of the spring 36 also lowers the arm 26 and consequently returns the valve disc 22 to its closed position, thereby conditioning the mechanism for a repetition of the function described. The switch 16 is also operated in the downward movement of the rod 20 to break the current supply to the motor 6 and the heating element 10.

The switch 16 is of the quick acting or snap type and as shown more or less diagrammatically ίο ’ ⁴’ h^{as a pair oi mova}b’^e contacts or blades 48, 48 and two pairs of fixed contacts 49, 50 The wires IS, 17 are connected to the fixed contacts 49, while the wires 18 are connected to the fixed contacts 50. The movable contacts 43 are connected for movement to unison and engage both secs of fixed contacts 49, 50 when the switch is m “on” or closed position. The movable con- ; tacts are out of engagement with the fixed contacts when the switch is in “off” or open position. The switch is shown to closed position in Fig. 4.

The motor 6 may be supported above the base : . by a bracket 51. The drier assembly including the blower, motor, and heating units and the timing mechanism are enclosed in a covering case 52 fitting on top of the base 21 and secured thereto. The blower is so mounted that it may be turned about the axis of the fan 2 to adjust the nozzle 4 up and down as required to suit the user of the device.

The details of construction and arrangement of parts shown and described may be variously changed and modified without departing from the spirit and scope of my invention except as pointed out in the annexed claims.