US 3857076 A
A vacuum cleaner structure having self-propelling means. A handle is associated with the vacuum cleaner and the self-propelling means to drive the vacuum cleaner in accordance with force applied forwardly or rearwardly to the handle. The handle is biased to an Off position. The driving force developed by the propelling means varies as a function of the displacement of the handle from the Off position.
Claims available in
Description (OCR text may contain errors)
United States Patent [191 Hetland 1 1 Dec. 24, 1974 UPRIGHT VACUUM CLEANER-DRIVE MOTOR CONTROL  Inventor: Thomas Erwin Hetland, White Bear Lake, Minn.  Assignee: Whirlpool Corporation, Benton Harbor, Mich.
 Filed: Jan. 115, 11973  Appl. No.: 323,780
 US. Cl 318/257, 318/295, 318/345  lnt. Cl. H02p 5/16  Field of Search 318/256, 257, 291, 293, 318/295, 313, 345, 260, 271, 276, 305, 416, 436
 References Cited UNITED STATES PATENTS I 3,402,338 9/1968 Thoresen 318/345 3,461,371 8/1969 Klayman 318/345 3,441,828 4/1969 Henry 318/345 3,475,676 10/1969 Hutson 318/313 3,551,787 2/1970 Walters 318/345 3,582,744 6/1971 Coffey 318/313 3,601,673 8/1971 Mason 318/345 3,628,115 12/1971 Pruitt 318/345 3,753,065 8/1973 Chiles 318/295 Primary Examiner-Robert K. Sehaefer Assistant ExaminerThomas Langer Attorney, Agent, or Firmllofgren, Wegner, Allen, Stellman & McCord  ABSTRACT A vacuum cleaner structure having self-propelling means. A handle is associated with the vacuum cleaner and the self-propelling means to drive the vacuum cleaner in accordance with force applied forwardly or rearwardly to the handle. The handle is biased to an Off position. The driving force developed by the propelling means varies as a function of the displacement of the handle from the Off position.
11 Claims, 24 Drawing Figures r 5 Sheets-Sheet l Patented Dec. 24, I'M
Patented Dec. 24, 1974 5 Sheets-Sheet I,
Patented Dec. 24, 1974 3,857,076
5 Sheets-Sheet 4 Patented Dec. 24, 197 3,857,076
5 Sheets-Sheet 5 BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to vacuum cleaners and the like, and in particular to an improved control means for use in propelling vacuum cleaners and the like.
2. Description of the Prior Art United'States Letters Patent which would appear to be pertinent to the present invention are as follows:
716,065 Ledwinka Automobile 1,076,652 I-Ioffmann Driving Mechanism for Vehicles 1,098,849 Smart et a1 Switch 1,242,l l5 Russel Switch for Dental Instruments 1,723,371 Pieper Combined Tool Handle and Switch 1,813,856 Klein Direct Drive for Antifriction Roller Bearing Free Wheels 1,953,340 Doemling Suction Cleaner 2,041,442 Stinsman Floor Polishing Machine 2,138,239 lrgens Self-Propelled Implement 2,348,053 Bowker Electrically Operated Motor Vehicles 2,706,008 Voigt Powered Golf Bag Carrier 2,823,41 1 Kirby Vacuum Cleaner 2,879,858 Thomas Battery Energized, Motor- Driven Vehicle 2,937,706 Chandler Self-Pro elled Carts 3,095,534 Cockrell Circuit or Controlling Energization of a Direct Current Load 3,195,029 Gilbreath Series Motor Control 3,222,582 Heyman et a1 Variable Speed Motor System Utilizing Controlled Rectifiers 3,225,853 Norton et a1 Control Handle for Golf Cart 3,354,496 .lonsson Suction Cleaner Nozzle of the Agitator Type 3,385,077 Marsteller Air Conditioner 3,475,676 Hutson Photosensitive Power Control System 3,489,874 Baumann Control Switch for an Electric Dry Razor Smart et a1. U.S. Pat. No. 1,098,849 show a switch adapted to be operated by the longitudinal movement of an actuating member.
Russell U.S. Pat. No. 1,242,l shows a longitudinal movable switch for use in a dental instrument. Pieper U.S. Pat. No. 1,723,371 shows a similar switch.
Klein U.S. Pat. No. 1,813,856 shows a drive having an electric motor for each of a plurality of wheels.
Doemling U.S. Pat. No. 1,953,340 shows a vacuum cleaner wherein an agitator is driven from an actuating motor separate from the fan motor.
Stinsrnan U.S. Pat. No. 2,041,442 shows a floor polishing machine having a fan for ventilating the motor elements.
lrgens U.S. Pat. No. 2,138,239 shows a self-propelled powered lawnmower having a handle grip for controlling forward and rearward movement of the lawnmower.
Bowker U.S. Pat. No. 2,348,053 shows a battery operated motor vehicle having a dynamotor within each wheel.
Voigt U.S. Pat. No. 2,706,008 shows a powered golf bag carrier having a worm gear arrangement providing increased power under heavy loading conditions and braking means to secure the carrier in a stationary position.
Kirby U.S. Pat. No. 2,823,411 shows a vacuum cleaner with the fan motor also driving a brush in the nozzle.
Thomas U.S. Pat. No. 2,879,858 shows a battery driven vehicle wherein the current supplied to the drive motor is varied in accordance with the tension applied to the handle thereof.
Chandler U.S. Pat. No. 2,937,706 shows a selfpropelled cart having a handle controlling the electric drive motor thereof with the amount of pull on the handle varying the force developed by the motor.
Cockrell U.S. Pat. No. 3,095,534 shows a circuit for controlling energization of a direct current load utilizing a controlled rectifier in controlling the current to the motor armature. Gilbreath U.S. Pat. No. 3,195,029 shows a series motor control using a controlled rectifier in similarly controlling the current to the motor armature. Heyman et a1. U.S. Pat. No. 3,222,582 shows a motor system utilizing controlled rectifiers.
Norton et a1. U.S. Pat. No. 3,225,853 show a control handle for a golf cart providing adjustable power as a function of the magnitude of the applied force.
Jonsson U.S. Pat. No. 3,354,496 shows a vacuum cleaner nozzle having an agitator driven by an electric motor.
Marsteller U.S. Pat. No. 3,385,077 shows an air conditioner wherein modulation of the air flow is controlled by an optical system utilizing a photocell. Hutson U.S. Pat. No. 3,475,676 shows a photosensitive power control system utilizing similar optical means.
Baumann U.S. Pat. No. 3,489,874 shows a control switch for an electric razor having an operating knob which is selectively slidable, pivotable, or rockable in the casing.
Thus, the prior art shows the concept of propelling means such as automobiles, lawnmowers, golf bag carriers, and golf carts by self-contained motor driven power means. The art further shows the use of pushpull, longitudinally movable controls such as in electric switches, dental instruments, lawnmowers, and golf carts.
The prior art further shows the use of vacuum clean ers having motor driven suction fans and motor driven agitators. Still further, it is known to use direct current motors for reverse driving of devices and to use controlled rectifier means for controlling the current flow to such a motor for varying the speed and torque thereof.
SUMMARY OF THE INVENTION The present invention comprehends a vacuum cleaner construction having new and improved control .means for effecting controlled self-propelling thereof.
indifferent embodiments of the invention. The cooling air may be drawn through the motor by the vacuum cleaner suction fan or may be delivered to the motor under pressure from the suction fan in different embodiments of the invention. The cooling air may comprise air from which dirt has been removed by the vacuum cleaner. Alternatively, the cooling air may comprise atmospheric air drawn by the suction fan concurrently with the drawing of the dirt laden air to the dirt separating means. The cooling air may be passed through the interior of the motor housing through suitable openings therein and may also be directed against the exterior of the housing by deflecting means such as the drive wheels as discussed above.
The drive wheels may comprise cup-shaped elements partially surrounding the motor housing while leaving a passage therebetween intermediate the ends of the motor housing for passing cooling air therethrough.
The means for controlling the operation of the propelling motor may include an electronic switch phase controlled to vary the current to the motor as a function of the position of the handle means. The control may function to provide power during each half cycle of the alternating current power supply. Alternatively, the control may function to provide current only during similar polarity half cycles of the alternating current power supply to selectively reversely operate the motor as a function of the selected polarity.
The phase controlled electronic switch may comprise a controlled rectifier. In one form, the rectifier comprises a bidirectional triode thyristor. In another embodiment, the rectifier comprises a silicon controlled rectifier. In one embodiment, the means for controlling the control gate of the controlled rectifier comprises a bidirectional trigger diode. In another embodiment, the means for controlling the control gate comprises a silicon unilateral switch.
Phase control of the controlled rectifier may be provided by varying a resistance in the control circuit thereof. In one embodiment, the variable resistance comprises a potentiometer. The potentiometer may have a gap in the mid-portion of the resistor thereof to provide an Off condition. In another embodiment, the variable resistor comprises a photocell and means for varying the amount of light striking the photocell from a light source for providing a low cost, long life adjustable resistance means. The means for varying the transmitted light may comprise a suitable mask positioned by the handle of the vacuum cleaner.
In another embodiment of control wherein the motor is operated only on similar polarity half cycles of the alternating current power supply, the variable resistance is connected to the means for triggering the controlled rectifier through a parallel inverse diode circuit. Selection of the polarity of the motor operating current may be obtained by connecting a potentiometer resistor across the parallel circuit with the slider of the potentiometer connected to the motor. Alternatively, selection of the polarity may be effected by a selector switch having the moving contact selectively engage- I able with fixed contacts connected one each to the different inversely connected diodes.
More specifically, the present invention comprehends the provision in a vacuum cleaner having an operating handle and a wheeled drive including an electric drive motor and wheels driven by said motor, of control means for controlling the propelling of the vacuum cleaner by the wheeled drive comprising a direct current motor, a full wave rectifier for supplying direct current to said motor from an alternating current power supply, an electronic switch in series with the motor having a control gate element, and means responsive to the position of the operating handle relative to an Off position thereof for controlling the control gate element and correspondingly providing phase controlled conduction of direct current through the motor during each half cycle of the alternating current power.
Further more specifically, the electronic switch thereof may comprise a bidirectional triode thyristor and the means responsive to the position of the operating handle for controlling the thyristor may include a bidirectional trigger diode having one terminal connected to the control gate element, parallel, inverse diodes connected to the other terminal of the trigger diode, a capacitor connected between the other terminal of the trigger diode and the power supply, and resistance means adjustably connected to the inverse diodes.
Further more specifically, alternatively, the invention comprehends the provision in a vacuum cleaner having an operating handle and a wheeled drive including an electric drive motor and wheels driven by the motor, of control means for controlling the propelling of the vacuum cleaner by the wheeled drive comprising a direct current motor, adjustable phase controlled means for providing current to the motor only during similar polarity half cycles of the alternating current power, and means for selecting the half cycle polarity during which the current is provided for selective reversible operation of the motor.
BRIEF DESCRIPTION OF THE DRAWING Other features and advantages of the invention will be apparent from the following description taken in connection with the accompanying drawing wherein:
FIG. 1 is a perspective view of a vacuum cleaner embodying the invention;
FIG. 2 is a fragmentary rear elevation thereof with portions of the rear cover of the bag enclosure removed to illustrate details;
FIG. 3 is a fragmentary bottom plan view thereof;
FIG. 4 is a fragmentary enlarged vertical section illustrating the handle switch control means;
FIG. 5 is a fragmentary vertical section illustrating the propelling means mounted to the carriage of the vacuum cleaner;
FIG. 6 is a diametric section taken substantial the line 6-6 of FIG. 5;
FIG. 7 is a schematic wiring diagram of the electric drive control;
FIG. 8 is a fragmentary plan view with portions broken away illustrating one embodiment of the invention wherein cooling air is delivered from the suction fan to the drive motor;
FIG. 9 is a fragmentary side elevation thereof;
FIG. 10 is a fragmentary side elevation thereof with the nozzle in a raised position;
FIG. 11 is a plan view illustrating another embodiment of the invention wherein cooling air is sucked through the drive motor to pass with dirt laden air to the dirt separating means;
FIG. 12 is a fragmentary side elevation thereof;
y along FIG. 13 is a fragmentary side elevation thereof with the nozzle in a raised position;
FIG. 14 is a plan view illustrating another embodiment of the invention wherein cooling air is drawn through the drive motor to the suction inlet of the fan;
FIG. 15 is a fragmentary side elevation thereof;
FIG. 16 is a fragmentary side elevation thereof with the nozzle in a raised position;
FIG. 17 is a fragmentary side elevation of the vacuum cleaner construction of FIG. 5;
FIG. 18 is a fragmentary side elevation thereof with the nozzle in a raised position;
FIG. 19 is a schematic wiring diagram of a modified form of electrical control of the drive means;
FIG. 20 isa schematic wiring diagram illustrating a still further modified control;
FIG. 21 is an elevation of a mask for use in thecontrol of FIGS. 20 and 24;
FIG. 22 is a schematic wiring diagram of yet another modified form of control;
FIG. 23 is a fragmentary schematic wiring diagram illustrating a modification of the control of FIG. 22; and
FIG. 24 is a schematic wiring diagram of yet another drive control embodying the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS In the exemplary embodiments of the invention as disclosed in the drawing, a vacuum cleaner generally designated is shown to comprise an upright vacuum cleaner having a nozzle 11 and an upstanding bag enclosure 12 provided with a front closure 51. The nozzle is mounted to a carriage 13 hereinprovided with rear wheels 14. A brush and beater bar 15 is mounted at the front of the nozzle to be driven from'the suction fan motor 16 by suitable means (not shown). Herein the vacuum cleaner is driven by a propelling means generally designated 17 comprising a drivemotor 18 and a pair of drive wheels 19 and 20 secured to the oppositely projecting shaft ends 21 and 22 of the drive motor. As
shown in FIGS. 5 and 6, the housing23 of the drive motor may be secured to the carriage 13 by a suitable bracket 24 and screws 25.
Wheels 19 and 20 define cup-shaped elements facing toward each other coaxially of the motor as illustrated in FIG. 6. Thus, wheel 19 defines an end wall 26 and a cylindrical side wall 27, and wheel 20 defines an end wall 28 and a cylindrical side wall 29. The distal end 30 of wheel side wall 27 is spaced longitudinally from the distal end 31 of side wall 29 to define a space 32 therebetween for passing cooling air.
As illustrated in FIGS. 5, 6, 8, 17 and 18, cooling air may be delivered from the suction fan 45 through a duct 33 to the'interior of motor housing 23 through an inlet opening 34 in the housing. After passing through the housing, the cooling air may exhaust through the opposite ends 35 and 36 of the housing. As shown in FIGS. 6 and 8 the cup-shaped wheels are spaced axially and circumferentially from the housing to define flow paths 37 whereby the air deflected by the wheels is delivered to the space 32 to exhaust to the atmosphere. As shown in FIG. 8, the dirt laden air is conducted to bag 39 by means of a duct 40 extending from the nozzle 11 into the enclosure 12 wherein the bag is received. A duct 41 connects the enclosure 12 to the suction inlet 42 of the fan 45. The shroud 43 extending about the fan motor 16 is provided with a discharge opening 44 for discharging air from the fan 45 to atmosphere. As shown in FIG. 8, the duct 33 opens through the shroud 43 for receiving a portion of the air delivered from fan 45 for delivery to the drive motor.
As shown in FIGS. l7 and 18, the nozzle 11 may be pivoted on the carriage 13 by means of a projection 46 on housing 12 engaging a lever 47 pivotally mounted on a bracket 48 carried by the carriage 13. Thus, the wheel drive 17 is maintained in engagement with the subjacent floor F while the nozzle may be pivoted to space the brush and beater bar above the floor level by suitable pivoting of the enclosure 12 on the carriage. Duct 33 maintains the connection between the suction fan and motor 18 in the different relationships of the nozzle and carriage, as illustrated in FIGS. 17 and 18.
Vacuum cleaner 10 is propelled on the subjacent floor by suitable energization of drive motor 18 as a result of pressure applied to a handle 49 upstanding from the bag housing 12, as illustrated in FIG. 1. As shown in FIG. 2, bag enclosure 12 includes a rear portion 50. Removal of rear closure 52 of housing 12 provides access to the space 520 within the rear portion 50. Handle 49 extends through the top wall 53 of the housing portion and is provided with a slide tube 54 internallycarrying a housing 55 defining a cam 56 selectively engageable with the actuator 57 of a first switch 58 and the actuator 59 of a second. switch 60. The switches are carried on the rear housing portion 50. A centering device generally designated 61 is mounted in housing 55 for centering the cam 56 between the actuators 57 and 59, as shown in FIG. 4.
More specifically, the centering device includes a rod 62 fixedly secured to the housing portion 50 by a pin 63. Rod 62 is provided with a pin 64 intermediate the ends 65 and 66 of housing 55. A first coil spring 67 extends coaxially about rod 62 to a washer 68 slidably mounted on the rod adjacent pin 64. A second coil spring 69 extends from housing end 65 to a washer 70 slidably mounted on rod 62 oppositely adjacent pin 64. Slide tube 54 further is provided with an actuator 71, as shown in FIG. 2, for controlling the setting of a potentiometer '72 carried on the housing portion 50. As further shown in FIG. 2, a control 73 is mounted on the housing portion 50 adjacent upper wall 53 and a cord reel 74 is mounted to the housing portion 50 at the lower opposite end with a power supply cord 75 extending from reel 74 outwardly through the housing for connecting the vacuum cleaner to a power source such as a conventionalwall receptacle (not shown).
Operation of the vacuum cleaner may best be understood by reference to the schematic electrical wiring diagram of FIG. 7. As shown, drive motor 18 illustratively comprises a permanent magnet direct current motor having an armature 76 connected between the moving contacts 60a of switch 60 and contacts 58a of switch 58. Direct current power is delivered to the motor 18 from alternating current power supply leads L1 and L2 connected to a full wave bridge rectifier 77 through a single pole, single throw interlock switch 78. The positive output terminal 77a of the full wave bridge rectifier is connected to fixed contacts 60b and 58b of switches 60 and 58, respectively. A resistor 79 and a resistor 80 are connected in series between terminal 77a and the negative terminal 77b of rectifier 77. Diode 81 is connected between terminal 77a and second fixed contact 60c of switch 60 and second fixed contact 580 of switch 58 and through a silicon controlled rectifier 82 to negative terminal 77b. Diode 81 is further connected through a second inversely related diode 83 to the potentiometer 72, having its slider 72a connected to a fixed resistor 84 and a drive motor speed selector switch 85. Switch 85, in turn, is connected through a fixed resistor 86 and a capacitor 87 to power terminal 77b. A silicon unilateral switch 88 has its gate 88a connected to terminal 89 between resistors 79 and 80. Switch 88 is connected from a terminal 90 between resistor 86 and capacitor 87 to the gate 82a of the silicon controlled rectifier 82. A resistor 91 is connected from rectifier gate 82a to power terminal 77b and a series connection of a resistor 92 and capacitor 93 is connected across the rectifier gate 82a. A jumper 72b is connected to the opposite ends of the resistor 720 of potentiometer 72.
As discussed above, longitudinal movement of handle 49 by the application of force thereto by the users hand, as shown in FIG. 1, causes a corresponding movement of cam 56, as shown in FIG. 4, to actuate either forward switch 60 or reverse switch 58 as a function of the direction of force application to the handle. Further, the amount of longitudinal handle movement effected controls the positioning of the slider 7221 of potentiometer 72 to control the silicon unilateral switch 88 and thereby control the amount of current passed by the controlled rectifier 82 thereby to control the speed and torque of the motor 18. As shown in FIG. 7, when forward switch 60 is closed, i.e., by a downward movement of cam 56 (FIG. 4), moving contact 60a closes with fixed contact 60b to provide power from positive power supply terminal 77a through motor armature 76, switch 58 and through the silicon controlled rectifier to negative terminal 77b. Phase control of silicon controlled rectifier 82 is effected by the setting of slider 72a relative to resistor 72c of potentiometer 72 so as to vary the amount the current passed by rectifier 82 depending on the amount of displacement of slider 72a from the center position 72d of resistor 72c.
Reversely, similarly, where the handle is moved rearwardly' so as to move cam 56 upwardly to close switch 58, positive power supply terminal 770 is connected through moving contact 58a of switch 58 to motor armature 76 and through switch 60 and silicon controlled rectifier to the negative power terminal 77b causing a reverse operation of the motor 18 under the speed control of potentiometer 72.
Electrical components of one control found to provide excellent functioning as described above, are as follows: I
Modified controls suitable for use in controlling the operation of a motor corresponding to motor 18 are illustrated in FIGS. 19-24. As shown in FIG. 19, a control generally designated 173 is shown to include a full wave rectifier 177 connected to the alternating current power supply leads L1 and L2. A selector switch 194 is connected to the output terminals 177a and [77b of the power supply for selectively connecting power supply terminal 177a to a motor terminal 195 or a terminal 196 and power supply terminal 177b concurrently to terminal 196 or terminal 195 as a function of the position of the vacuum cleaner handle. The means for controlling current through the motor 181 comprises a controlled rectifier illustratively comprising a bidirectional triode thyristor, or triac, 197 having its gate 197a controlled by a bidirectional trigger diode, or diac, 198 connected in series with a fixed resistor 199 and a potentiometer 172 to a terminal 200 connected between motor 181 and triac 197. Triac 197 is connected between motor 181 and terminal 196 and a capacitor 201 is connected from a terminal 202 between diac 198 and resistor 199 and terminal 196 and the resistor 1720 has its opposite ends connected by a jumper 172b.
Thus, current flow to motor 181 is controlled by the triac 197 under the phase control of diac 198 which, in turn, is controlled by the setting of potentiometer slider 172a and switch 194 by the vacuum cleaner handle to provide selectively reversible operation of the vacuum cleaner wheeled drive motor at different speeds and torques as desired.
As shown in FIG. 20, the portion of the control 173 connected to terminals 195 and 196 may be modified to utilize a photocell 203 in lieu of potentiometer 172 as a variable resistance for controlling the diac 198. A neon lamp 204 may be connected between terminals 195 and 196 for directing light to the photocell 203. A mask 205 carried for movement with the vacuum cleaner handle 49 is interposed between lamp 204 and photocell 203 to control the resistance of the photocell. As shown in FIG. 21, the mask 205 includes an opaque portion 205a defined by downwardly opening cusps 205b and upwardly opening cusps 205C for varying the amount of light received by the photocell as a function of the movement of the mask from a centered position under the control of the vacuum cleaner handle. The control of FIG. 20 thus provides an improved long life control as frictional wear of control elements is avoided.
Referring to FIGS. 22-24, further modified control means for controlling a wheeled drive motor 183 of the vacuum cleaner are shown to provide such control under half wave voltage conditions. More specifically, as shown in FIG. 22, motor 183 may be connected through a triac 1973 across the alternating current power supply leads L1 and L2. The triac is phase controlled by a diac 1983 connected to its gate 197a. A capacitor 2013 is connected from power supply lead L2 to terminal 202. A fixed resistor 1993 is connected from terminal 200 to the slider 172a of potentiometer 1723 having its resistor 172; connected between parallel inverse diodes 206 and 207 which, in turn, are connected to terminal 202. Resistor 1720 preferably has a relatively high value, such as 4 or 5 megohms, and thus prevents triggering of the triac 1973 when in the center position, as shown in FIG. 22. However, when the vacuum cleaner handle is moved in either direction to correspondingly move the slider 172a, the triac is triggered during similar half cycles of the alternating current power supply. Thus, illustratively, when the slider 172a is moved upwardly, as seen in FIG. 22, the triac is triggered on positive half cycles and when the slider is moved downwardly, the triac is triggered on negative half cycles. Further, as the total resistance of the circuit through the diode varies as the amount of movement of the slider 172a, motor 183 is controlled not only as to direction of movement, but also as to speed and torque by the phase control of triac 11973 by diac 1983.
As shown in FIG. 23, the potentiometer may be provided with a modified resistor 172d having a gap l72e at the center portion so that when the slider 172a is in the center'position, the control will be in an Off condition as no current can flow to the diac 1983 from terminal 200.
Referring now to FIG. 24, a further modified control is shown to comprise a control similar to that illustrated in FIG. 22 but wherein the variable resistance is provided by photocell 2035 in lieu of the potentiometer 172 and the switching function is provided by a selector switch 208 having its moving contact 208a connected in series with the photocell 2035, one fixed contact 208b connected to diode 2075, and a second fixed contact 2080 connected to diode 2065. The resistance of photocell 2035 is controlled by lamp 2045 and mask 205 as described above relative to the control of FIG. 20. Switch 208 is operated by handle 49 concurrently with the moving of mask 205 to provide the desired reverse operation of vacuum cleaner drive motor 185 concurrently with the speed and torque control thereof by the control of the variable resistance of photocell 2035. The control of FIG. 24 is similar to the control of FIG. 22 in that the operation of the motor 185 is by similar polarity half cycles of the alternating current power supply by means of the inverse parallel diodes 2065 and 2075.
Illustrative circuit components for the elements of the controls of FIGS. 19-24 are as follows:
172 potentiometer -1 Megohm 177 Full wave rectifier 200 Volt PRV, 4 amp. 181 Motor American-Lincoln PM DC 194 Selector switch DPDT 197' Triac GE, SC 40B 198 Diac GE, ST-2 199 Resistor 30 Kilohms 201 Capacitor 0.1 rnfd 182 Motor American-Lincoln PM DC 1972 Triac GE, SC 408 1982 Diac GE, ST-2 1992 Resistor 30 Kilohms 2012 Capacitor 0.1 mfd 203 Photocell Vactec VT-lOlH 204 Lamp Signalite Neon 1723 Potentiometer 0-1 Megohm 183 Motor American-Lincoln PM DC 1973 Triac GE, SC 408 1983 Diac GE, ST-2 1993 Resistor 30 Kilohms 2013 Capacitor 0-1 mfd 206 Diode 1N 1694 207 Diode IN 1694 1724 Potentiometer 0-1 Me ohm 2064 ode 1N 169 2074 Diode IN 1694 185 Motor American-Lincoln PM DC 1975 Triac GE, SC 403 2035 Photocell Vactec VT-lOl H 2065 Diode IN 1694 2075 Diode IN 1694 2045 Lamp Signalite Neon The modified controls of FIGS. 119-24 function in the vacuum cleaner structure similarly to the control 73 except as otherwise noted above.
Referring now to FIGS. 111-116, the vacuum cleaner construction may include modified means for effecting the delivery of cooling air to the drive motor 18 by means of the suction fan 45. Thus, as shown in FIGS. 11-13, a duct 209 may be connected between the motor housing opening 341 and the suction duct 40 leading from the nozzle 11 to the dirt collecting chamber 38. Thus, the suction pressure effected by fan 45 serving to draw dirt laden airinto the vacuum cleaner concurrently serves to draw air through the motor housing 23 to cool the drive motor by sucking the air therethrough to the dirt separating chamber.
Referring now to FIGS. 114-116, a further modified form of vacuum cleaner construction embodying the invention is shown to include a duct 210 connecting the motor housingopening 3410 directly to the suction inlet 420 of the fan 4150 defined by the shroud 430. Thus, the cooling air sucked through the drive motor is delivered directly to fan 450 rather than through the dirt separating chamber as in the embodiment of FIGS. 111-113. In all other respects, the vacuum cleaner constructions of FIGS. 11-16 are similar to the vacuum cleaner construction illustrated in FIGS. 8-10 and similar elements thereof are identified by related reference numerals.
Thus, the vacuum cleaner constructions of the present invention provide an improved facilitated propelling of the vacuum cleaner over the surface to be cleaned. The drive motor of the propelling means and the suction fan of the vacuum cleaner are cooperatively associated for improved efficiency and low cost of the unit. Improved trouble-free, long life control means are provided for effecting desired reversible driving of the propelling means. The vacuum cleaner constructions of the present invention are extremely simple and economical of manufacture while yet providing the highly desirable features discussed above.
The foregoing disclosure of specific embodiments is illustrative of the broad inventive concepts comprehended by the invention.
I. In a vacuum cleaner having a selectively positionable operating handle and a wheeled drive including an electric drive motor, conductor means for connecting the vacuum cleaner to an alternating current power supply, the wheels driven by said motor, control means for controlling the propelling of the vacuum cleaner by said wheeled drive comprising: a direct current motor; a bidirectional triode thyristor in series with said motor and said conductor means and having a control gate element; and means responsive to the position of said op erating handle relative to an Off position thereof for controlling said control gate element and correspondingly providing phase controlled conduction of direct current through said motor during similar polarity half cycles of the alternating current power, including a bidirectional trigger diode having one terminal connected to said control gate element, parallel connected inverse diodes connected to the other terminal of said trigger diode, a capacitor connected between said other terminal of the trigger diode and said conductor means, and adjustable means including adjustable resistance means electrically connected in series with said inverse diodes and said trigger diode, and to said conductor means, said adjustable resistance means including a first resistance portion having a terminal connected to one of said diodes, a second resistance portion having a terminal connected to the other of said diodes, and means interconnecting said resistance portions opposite from said terminals to said conduction means, the adjustable resistance means being adjusted in response to positioning of said handle relative to said Off position and providing preferential current flow through a selected one of said diodes depending on the direction of movement of said handle from said Off position.
2-. In a vacuum cleaner having a selectively positionable operating handle and a wheeled drive including an electric drive motor, conductor means for connecting the vacuum cleaner to an alternating current power supply, and wheels driven by said motor, control means for controlling the propelling of the vacuum cleaner by said wheeled drive comprising: a direct current motor; a first, bidirectional electronic switch means in series with said motor and said conductor means and having a control gate element; and means responsive to the position of said operating handle relative to an Off position thereof for controlling said control gate element and correspondingly providing phase controlled conduction of direct current through said motor during similar polarity half cycles of the alternating current power to operate said drive motor selectively in either a forward driving direction or a rearward driving direction, including a bidirectional trigger diode connected to said control gate element, parallel connected inverse diodes connected in series with said trigger diode, and manually operable adjustable means electrically connected in series with said inverse diodes and said trigger diode, and to said conductor means, said adjustable means being responsive to the direction and magnitude of displacement of said handle from said Off position for causing preferential conduction of current through a corresponding selected one of said inverse diodes for causing said second electronic switch means to control said first electronic switch means to effect said selec tive controlled'operation of said drive motor.
3. The vacuum cleaner means of claim 2 wherein said control means includes biasing means urging said handle to said Off position when the handle is released.
4. The vacuum cleaner control means of claim 2 wherein said adjustable means includes variable resistance means.
5. The vacuum cleaner control means of claim 4 wherein said resistance means comprises a potentiometer having its resistor connected between the inverse diodes, and its slider connected to a fixed resistor.
6. The vacuum cleaner control means of claim 4 wherein said resistance means comprises a potentiometer having its resistor connected between the inverse diodes and its slider connected to said motor through a fixed resistor.
7. The vacuum cleaner control means of claim 4 wherein said resistance means comprises a potentiometer having its resistor connected between the inverse diodes and its slider connected to said motor, the resistor of said potentiometer having a gap at the center thereof for defining an Off arrangement when the slider is positioned at said gap.
8. The vacuum cleaner control means of claim 2 wherein said adjustable means comprises photocell means and means for varying the amount of light striking the photocell means as a function of the position of said handle.
9. The vacuum cleaner control means of claim 2 wherein said adjustable means comprises photocell means, light source means for actuating the photocell means, and mask means interposed between the photocell and light source means for varying the amount of light falling on said photocell means from said source means as a function of the position of said handle for causing said photocell means to control operation of the motor.
10. The vacuum cleaner control means of claim 9 wherein said adjustable means further comprises selector means for selectively connecting the photocell means alternatively to either of said inverse diodes comprising a double throw switch arranged to be operated by said handle.
11. The vacuum cleaner control means of claim 2 wherein said bidirectional trigger diode has one terminal connected to said control gate element, said inverse diodes being connected to the other terminal of the trigger diode, said means for controlling the control gate element further including a capacitor connected between said other terminal of the trigger diode and said power supply, and said adjustable means comprises resistance means.