|Publication number||US2911812 A|
|Publication date||Nov 10, 1959|
|Filing date||Nov 6, 1957|
|Priority date||Nov 6, 1957|
|Publication number||US 2911812 A, US 2911812A, US-A-2911812, US2911812 A, US2911812A|
|Inventors||Metzger Matt F|
|Original Assignee||Gen Electric|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (2), Referenced by (10), Classifications (6)|
|External Links: USPTO, USPTO Assignment, Espacenet|
Nov. 10, 1959 Filed NOV. 6, 1957 M. F. METZGER 2,911,812 MULTIPLE EXTRACTION SPEED LAUNDRY MACHINE HAVING "UNBALANCE SENSING MEANS 2 Sheets-Sheet 1 64 INVENTOR. Fl 6. 4 MATT F. mzrzasn HIS A'rrdnucv Nov. 10, 1959 M. F. METZGER 2,911,812
MULTIPLE EXTRACTION SPEED LAUNDRY MACHINE HAVING UNBALANCE SENSING MEANS Filed Nov. 6, 1957 2 Sheets-Sheet 2 FIG.Z
MATT F. Mn'zeen HI! ATTORNEY United States Patent MULTIPLE EXTRACTION SPEED LAUNDRY MA- CHINE HAVING UNBALANCE SENSING MEANS Matt F. Metzger, Jeifersonville, Ind., assignor to General Electric Company, a corporation of New York Application November 6, 1957, Serial No. 694,764
5 Claims. (Cl. 68-12) My invention relates to automatic laundry machines of the type having a rotatable clothes basket which is rotated at a relatively low speed to tumble the clothes in order to wash them, and at a plurality of higher speeds for centrifugal extraction of the wash liquid from the clothes; and more particularly it relates to means included in such machines for returning the machine from the higher extraction speeds to low speed rotation upon an unbalance which would cause excessive vibration of the machine, until the clothes are properly balanced to eliminate the vibration whereupon the speed of rotation of the basket is increased to resume the extraction operations.
More specifically, this invention relates to laundry machines of the type provided with a driving means, such as an electric motor, and a two speed transmission unit for the basket. The basket is driven at a relatively low tumbling speed for washing when the motor is operated with the transmission unit set for low speed output and at a relatively high Water extraction speed when the motor drives the basket with the transmission set for high speed output. This invention is especially applicable to machines of this type where a two speed motor as well as a two speed output transmission unit is provided. In machines of this character the motor is driven at one of the motor speeds with the transmission set for low speed output for driving the basket at clothes washing tumbling speed and is driven selectively at both motor speeds with the transmission set for high speed output in order to drive the basket at each of two relatively high water extraction speeds.
It will be understood that regardless of which of these combinations of speeds are utilized when the rotating basket proceeds from the relatively low basket speed washing or rinsing step into its high speed centrifugal extraction step, vibration of the rotating basket and its enclosing tub structure increases substantially unless the clothes distribute themselves evenly around the basket. Unless the clothes are approximately evenly distributed, the basket is dynamically unbalanced and depending upon the de gree of unbalance, excessive vibration may occur.
To prevent excessive vibration in the above described machine which has a single extraction speed only, one method of control has been to measure or sense the vibration as the basket proceeds into the higher speed operation; if the vibration were excessive, a suitable switch has been actuated to control the machine to return the basket to its lower speed. Actuation of that switch has served to shift the transmission to its lower gear ratio, that is, to
its lower speed. This has given the clothes a chance to reorient themselves within the basket at the lower speed. After a suitable time delay the switch has been operated reversely so as to attempt again the higher speed of rotation by shifting the transmission to its higher speed. Usually, the clothes have been distributed properly so that centrifugal extraction at the single extraction speed could proceed without delay. If, however, they have not done so, the basket once more has returned to the lower speed operation to allow them to rerorient again. .This
action has been repeated until the clothes have distributed evenly enough to reduce vibration to an acceptable level.
This known method of control, while ithas proven successful in the more simplified machine, is not suitable for the more advanced machine described above. This is because when the machine uses two-speed driving means for driving a two-speed transmission, generally provision must be made for changing the speed of the two-speed driving means, in addition to providing for the changing of the gear ratio of the transmission in order to eliminate excessive vibration. Otherwise, the basket may be driven at a fourth speed intermediate the slow speed at which the clothes may 're-orient themselves and the slower of the extraction speeds at which no such re-orientation is practicable. Such an intermediate basket speed is undesirable in that the clothes may not re-orient their position at that speed and thus, a continued repeating of the switch operation would ensue without correction of the unbalanced condition.
An object of the present invention is to provide an improved laundry machine vibration elimination control means adapted for use into a machine having at least two extraction speeds and a single clothes tumbling speed, with operation at both extraction speeds being under automatic control of vibration sensing means which upon actuation returns the machine to the single predetermined tumbling speed. V p
In accordance with the invention, as applied to the more advanced laundry machine having a rotatable clothes basket driven by a two speed motor through a two speed transmission assembly, I provide a first electrical control means, such as a solenoid, for instance, for selecting one of the two transmission assembly speeds, and second electrical control means, such as the connec tions of a two'speed motor, for selecting one of the two driving means speeds. In addition, there are provided a timer motor and suitable cam means operated by the timer motor. i I g Switch means are provided to control the first electrical control means and the timer motor so that in one position of the switch means the higher transmission assembly speed is provided for and operation of the timer motor is precluded, and in the second position the lower transmission speed is provided and the timer motor is ener gized. Second switch means for controlling the driving means are provided with two operating positions which provide respectively the first driving means speed and the seconddriving means speed, the second speed represent ing the proper tumbling speed when the transmission is connected for low speed output. Also, suitable means are provided for sensing the magnitude or vibration of the clothes basket during the extracting process, and for actuating the first switch means to its second position when the vibrations become undesirably large. This starts the timer motor which in turn operates the cam means and causes it to move the second switch means from its first position to its second position. After a suitable period of rotation ofthe cam means, it is then operative to actuate both switch means, returning the first switch means to its first position to stop the timer motor and reconnect the transmission assembly for high speed'and actuating the second switch means so as to move it from its second operating position to its first operating position. Where the sequence of the laundry machine is such that the extraction speed provided by the second driving means speed is desired in any event,
a sequence control means is operative to bypass the second switch means and run the driving means at its second speed at the desired predetermined times regardless of what the second switch means is doing; With this arrangement, the desired tumbling speed is obtained upon an imbalance in the clothes basket byactuation of the vibration sensing means and this is done regardless of the extraction speed. In other words, the danger of having the undesirable fourth speed which is inappropriate for tumbling is obviated.
The features of my invention which I believe to be novel are set forth with particularity in the appended claims. My invention itself, however, may be best understood by reference to the following description taken in conjunction with the accompanying drawings in which:
'Fig. -1 is a front elevational view of a domestic laundry machine showing vibration sensing means arranged in accordance with this invention, certain surfaces of the view being broken away in order better to illustrate certain details;
Fig. 2 is an enlarged side elevational view of the machine of Fig. l with the side panel removed, the view being partly in section and having certain surfaces broken away to illustrate certain details;
Fig. 3 is a fragmentary plan view of drive means included in the machine; and
'Fig. 4 is an elevational view of a preferred embodiment of my improved switch operating device for a twospeed motor and a two-speed transmission assembly, the view also showing schematically a control circuit forthe laundry machine.
Referring now to Fig. l, 'I have shown my invention in one form as applied to a domestic laundry machine 1, comprising a combination washer and dryer. The machine 1 includes an outer cabinet 2, which is mounted on a-supporting base structure 3. Access to the machine for loading and unloading of clothes is provided by a hinged door 4 disposed in the front wall of the cabinet. A backsplasher 5, mounted at the top of the cabinet, serves as a mounting means for suitable operator controls for the machine. These controls may, for example, comprise the rotatable dials 6 and 7, and the pushbuttons 8.
The machine 1 is of the type-which includes a clothes basket rotatable about a non-vertical axis; specifically, it includes a perforated basket 9 which is disposed for rotation about a generally horizontal axis. The basket 9 is mounted within an imperforate tub structure 10, which encloses it on all sides. The basket is rotatably supported from the tub structure by a horizontally extending shaft 11 'which is mounted in an elongated bearing '12 hung from the rear wall 13 of the tub structure. The shaft 11, as well as supporting the basket, also serves as a means for turning it during operation of the machine. The tub and basket are provided, respectively, with openings 14 and 15 in the front walls thereof, which are aligned with the door opening in the front wall of the'cabinet 2 so that clothes may be placed into or removed from the basket. The door 4 seals against a-gasket 16 around the tub opening 14 to close off the tub completely during operation of the machine.
The tub is supported from the base 3 by means of aplurality of brackets or arms 17 which are mounted on upstanding plates 18 fixedly attached to the base 3. Four of these arms 17 are provided, two being secured to each side of the tub. The arms on the opposite sides of the tub are spaced apart as shown in Fig. 2 so that the tub in effect is supported near its front and near its rear on each side thereof. Although the arms 17 can be secured directly to the wall of tub 10, preferably and as shown, the arms 17 are attached thereto by means of suitable brackets 19. With the tub 10 supported in the manner shown, it is able to vibrate sideways in a plane parallel to the front of the machine if the basket 9 should be unbalanced during a high speed rotation thereof. The arms 17 are relatively long compared to their width, and they flex so as to allow slight sideways vibration of the tub relative to the base 3. However, the arms 17 are effective substantially to prevent vibration vof the ,tub both from front to rear and in the vertical direction. The arms are not at all flexible in those directions so that normally front to rear and :up and down vibration 4 of the tub cannot occur. Only sidewise vibration can occur. As is'more fully explained hereinafter, I provide means for sensing the amount of sidewise vibration thereby to prevent that vibration from ever becoming great enough to damage the machine or to cause it to move on the floor.
During the operation of the machine, the basket 9 is driven from suitable two speed means, such as two-speed electric motor 20, through a drive, including a transmission assembly 21 and a pair of flexible belts 22 and 23 (see Figs. 2 and 3). The belt 22 connects the output pulley 24 of the motor to the input pulley 25 of the transmission assembly. The belt 23 connects the output pulley 26 of the transmission assembly to a basket drive pulley 27 mounted on the shaft 11 of the.clothes tumbling basket 9. The transmission assembly 21 is of the multiple speed type, that is, the gear ratio thereof can be changed so that the basket is driven at two different speeds for a given speed at which the pulley 25 of that assembly is being driven. The two speed motor 20 may, of course, be of any suitable construction; in the present case, -Ihave chosen to use an induction motor (see Fig. 4) having a four-pole, high speed winding 30, a six-pole low speed winding 31, a starting winding 32 and a centrifugal switch 33 for regulating the circuit to those respective windings. Thus, the output pulley 24 of the motor may be driven at either of two speeds to turn the input pulley 25 of the transmission assembly at either of two speeds.
The ratio of the transmission assembly input to output speeds is changed by any suitable means such as spring biased, solenoid operated plunger 34. When the electrically operated solenoid 35 controlling the plunger is de-energized, the transmission ratio is such that the basket is driven at a suitable speed for washing and tumbling clothes, for example, 45 revolutions per minute and, and as will later become apparent, the motor 20 at this time can operate only upon its low speed winding. However, when the solenoid 35 is energized, the plunger 34 changes the ratio of the transmission so that the basket is driven at either a first, or lower extraction speed, for example, 200 revolutions per minute, or at a second, or higher extraction speed, for example, 300 revolutions per minute, depending upon the speed provided by the motor, as determined by the sequence control means for the machine. My invention, therefore, provides one basket speed for clothes tumbling and either of two other different basket speeds for centrifugal extraction.
The complete operation of the machine normally provides a washing period during which basket 9 rotates at a tumbling speed of approximately 45 r.p.m., water extraction period with rotation at, for instance, either 200 or 300 r.p.m. or a combination thereof, a rinse at 45 r.p.m., another spin, and, if desired, a drying period at 45 r.p.m. While variations of this sequence can be provided, it will be understood that the described sequence is typical and is provided by standard control apparatus in the usual manner.
During the operation of the machine, the various electrical components thereof are under the control of a timer operated sequence control indicated schematically at 36 in Fig. 4. A suitable sequence control and a complete circuit for the machine 1 are shown, for instance, in copending application Serial No. 512,612 filed June 2, 1955, by Walter E. Gray, Ir., now Patent No. 2,892,334 owned by General Electric Company, assignee of the present application. In addition to the elements illustrated herein and now to be described, it will be understood that the sequence timer 36 also controls suitable means whereby water is admitted to and discharged from the machine and suitable heating means within the machine. A water inlet connection 28 and a sheathed type resistance heater 29 are both shown in Fig. 2. Any suitable electrically actuated means, such as a drain pump (not shown) can be used to control the discharge of water from the machine.
' The sequence control is energized by means of a 'pair of supply conductors 40 and 41. During the extraction operation of the machine suitable switch means such as double throw switch 42 occupies either its upper position bridging contacts 43, 44, or its lower position bridging contacts 45, 46. As will be more fully described, this provides constant energization of the drive motor 20. In addition, a suitable single throw switch 47 is closed across contacts 48, 49 during extraction operation of the machine; contact 48 is connected to one terminal 50 of the unbalance timer motor 51. The circuits through those switches will later be described in connection with the several stages of rotation of the basket as influenced by the vibration sensing means.
Referring now to Fig. 4, I provide a vibration sensing means which includes a first, or unbalance, switch 52 having a'pivoted blade 53 movable between a first setting at which it closes a circuit at terminal 54 and a second setting at which it closes a circuit at terminal 55. At its pivot end, the blade is connected to terminal 56. Movement of the blade is effected by inward movement of oppositely disposed independently actuated projecting members, or push buttons, 57 and 58.
In the embodiment illustrated, the switch 52 is mounted on the base 3, and is actuated by means of a depending bracket 59 on the tub. Between the bracket and the switch is interposed a switch operating device generally indicated at 60, this device being operative to transmit the motion of the bracket to the switch. The device may conveniently be mounted on the base of the machine by an upstanding support bracket 61, also serving to support other portions of the vibration sensing means, later to be described. The switch operating device comprises an adjustable scissors arrangement including a pair of pivoted arms 62 and 63. These arms are both pivotally mounted on a pin 64 which is supported by means of the bracket 61. The one arm 62 of the scissors engages the bracket 59 on the tub so as to be moved thereby, and the other arm 63 is actuated by the arm 62 so as to operate the switch button 57 upon a sufficient movement of the tub. In order to transmit the movement of the arm 62 to the arm 63, there is disposed between the arms a dual purpose coil spring 65. This spring 65 is mounted by means of bosses 66 and 67 formed respectively on the two arms, and it is strong enough so that it is not ordinarily compressed by the movement of the arm 62. Rather, it transmits the motion of the arm 62 to the arm 63 so that the arm 63 is moved thereby against the switch button 57.
In order to adjust the scissors device 60 so that the switch 52 will be operated upon a predetermined vibration of the tub, the normal position of the arm 63 is pre-set so that there is a predetermined relationship between it and the switch button 57. Depending upon the permissible vibration of the tub and the distance the button 57 must be pushed into the switch housing before operating the switch, the arm 63 may be pre-set with a predetermined gap between it and the switch button 57, or it may be set so that it directly engages the switch button.
In order to preset the position of the arm 63 there is provided a third pivoted member 68 which is also mounted by means of the pin 64. This pivoted member is provided with a tab 69 which extends into a curved slot 70 in the arm 63. The spring 65 biases the arm 63 to the right as viewed in Fig. 4 so that normally the tab 69 is engaged with the extreme left hand end of the slot. With this relationship between the arm 63 and the member 68, it will be seen thatby adjusting the'position of the member 68, the normal position of the arm 63 may be changed. To determine the normal position of the member 68 adjusting means are provided, including a spring 71 and an adjustable stop 72. The spring 71 is disposed between a hook 73 on member 68 and a projection 74 on the support member 61 and it pulls member 68 into contact with the stop 72.
' In the embodiment illustrated, the stop 72 comprises a movableslide which may be adjusted by'means of a screw 75. The screw 75 has an eccentric shoulder, not shown, and the eccentric shoulder directly'engages the slide so that, as the screwis turned, the slide is moved to the right or left, as viewed in Fig. 4. YA. tightening screw 76 is provided for bolting the slide in its final position of adjustment. Since the spring 71 biases the pivoted member 68 against the slide 72, adjusting the position of the slide also adjusts the normal position of the pivoted member; and due to the engaging means 69 and 70 between the member 68 and the arm 63, this also results in an adjustment of the normal position of the arm 63 relative to the switch button 57 of unbalance switch 52.
By means of the described arrangement the final setting of the various parts of the vibration sensing means may be readily accomplished at the site of installation of the machine. As shown, a screw 77 is mounted in member 68, and extends through a slot 78 in the arm 62. This screw normally locks member Y68 and arm 62 together. However, when it is loosened to effect final adjustment of the switch at the site of installation of the machine, the arm 62 is freed so that it may be moved by the spring 65. The machine is normally shipped from the factory with arm 62 retracted from tub bracket 59, so that the screw 77 is at the left end of the slot 78 when viewed in Fig. 4. Then, upon the loosening of the screw, the spring 65 biases the arm 62 into direct engagement with the bracket 59. Once this movement has been completed, the screw 77 is then retightened so as to lock the arm 62 and the member 68 together again.. This completes the adjustment of the unbalance switch 52. I
The spring 71 is stronger than the spring 65 and thus the arm 63 does not move when screw 77 is loosened. Rather, the arm 63 remains in its same pre-set relationship relative to the switch as given to it at the factory. With the same pre-set relationship existing between the arm 63 and the switch button 57 and with the arm 62 resting di- 'rectly against the actuator bracket 59, it will be seen that the unbalance switch will be actuated at the exact amount of tub vibration which was selected when the arm 63 was positioned relative to the switch 52 at the factory.
As will be apparent, the spring 65 serves two purposes". It serves as a biasing means for effecting the automatic adjutment of the arm 62 when screw 77 is loosened and it serves as yieldable means for transmitting the motion of the one arm to the other, which means allows relative movement between the arms upon overtravel of the tub thereby to prevent damage to the switch. In the above description, and in the drawings, I have shown the unbalance switch and the scissors device 60 as mounted on the base 3 and the switch actuator 59 as mounted on tub 10. However, it is obvious that their positions could be reversed and the same results would be obtained.
Having thus described the vibration sensing means for transmitting motion of the tub to the unbalance switch 52, it will be understood that one purpose of this switch is to temporarily de-energize the solenoid coil 35 if the vibration exceeds a preselected permissible limit, for example, thirty (30) thousandths of an inch in amplitude,
by moving blade 53 out of contact with terminal 54. In order to reenergize that coil by resetting of that switch, I provide an unbalance timer motor 51, energized when blade 53 engages terminal 55 in response to actuation by button 57, which drives a cam 80 counterclockwise, as seen in Fig. 4. As it rotates, the cam is adapted to engage the upper end of a leaf spring 81, which is fixedly mounted at its lower end on the bracket 61. During rotation this cam bends the upper end of the spring to the right (as viewed in Fig. 4). This bending of the leaf spring continues until such time as the spring is bent far enough that the lobe of the cam can slip over its top. At that time, the spring snaps in the opposite direction striking the button 58 of the switch 52. The button 58. is thereby actuated and shifts the switch blade 53 thereby to connect the terminals 54 and 56and to disconnect'the terminals 55 and '56. In so doing, the circuit from terminal 55 through conductor 82 to terminal 83 of the timer motor 51 is interrupted and the motor stops. At the same time, the circuit from closed switch 47 of the sequence control means 36, through conductor 84, solenoid coil 35, conductor '85, switch terminal 54, switch blade 53, terminal 56, conductor 86, and return conductor 87 is established. A connection is at all times made to terminal 50 of the timer motor 51 by branch conductor '88, while switch47 is closed, thus holding that timer mo- .tor in readiness to operate instantly as soon as switch blade 53 is moved from terminal 54 to terminal 55 by an unbalanced condition of the tub. It will be understood that when the circuit through solenoid coil 35 is interrupted, the plunger 34 is actuated to shift the transmission assembly to its lower .gear ratio. When the circuit through the coil 35 is established, however, the plung- 1er is actuated to shift the transmission so that it may be driven at one or the other of the higher extraction speeds, depending upon the circuits to the windings of the twospeed drive motor.
Referring now to Fig. 4, I provide second switch means in the form of motor speed switch 90 having a pivoted switch blade 91 connected at one end to terminal 92 and shiftable at its other end between terminals 93 and 94. The circuit to the motor windings is dependent on the settings of both switch 90 and switch 42 of the sequence control means 36, as will be further described. It will be understood that the actuation of unbalance switch 52 and rotation of timer motor 51 can occur at any time when an unbalanced condition arises in the basket, and thus may occur while the backet is being driven either at the lower extraction speed or at the higher extraction speed. The particular operative extraction speed is generally determined by the time which has elapsed in the cycle of machine operation, as reflected by the operation of the sequence control 36.
Thus, when the machine is in its higher extraction speed phase, the switch 42 of the sequence control bridges terminals 45 and 46. Assuming no unbalance condition at this time, the following circuit is in operation. Switch blade 91 connects terminals 92 and 94, and a lobe of cam 80 (the motor 51 being de-energized) rests against a second leaf spring 95 which presses upon aprojecting member, or switch button, 96 holding the switch blade 91 to the right as viewed in Fig. 4. This second leaf spring is fixedly mounted at the lower end of the housing of switch 90.
Under this set of conditions, current flows through conductor 97 from supply lead 41, through switch 42, conductor 98, terminal 92, switch blade 91, terminal 94, conductor 99, conductor 100 to centrifugal switch 33, starting winding 32, return conductor 87, to supply lead 40. At the same time, a parallel circuit through conductor 101, high speed Winding 30 and conductor '87, energizes the high speed winding. Upon starting of the motor through this high speed winding, centrifugal switch 33 operates to remove the starting winding 32 from the circuit and to connect the low speed winding 31 with conductor 102 leading to switch terminal 43. However, since sequence control switch 42 is now calling for motor operation at the higher extraction speed by engagement with terminals 45 and 46, no current flows through the low speed winding and the motor continues to operate at its higher extraction speed. Moreover, since the solenoid 35 is now receiving current through switch 52, the plunger 34 holds the transmission assembly at its higher gear ratio and the basket rotates at the higher extraction speed, for example, 300 revolutions per minute.
When the machine is in its lower extraction speed phase, the switch 42 of the sequence control bridges terminals 43 and 44. Assuming no unbalance condition at this time, the following circuit is in operation. Switch blade 91 as before is connecting terminals 92 and 94. Current then flows .through conductor -97 from supply lead 41, through switch 42, conductor 103, switch '33, starting winding 32, return conductor 87, to supply lead 40. At the same time, a parallel circuit through conductor 100, high speed winding 30 and return conductor 87 energizes the high speed winding. Thus, it will be seen that whenever two speed motor 20 begins to or:- erate, it so begins by energization of its high speed winding. When, however, the sequence control calls for the lower extraction speed with switch 42 bridging contacts 43, 44, the centrifugal switch 33 immediately upon the motor coming up to speed opens the described circuits through the starting winding 32 and the high speed winding 30. At this time, the switch 33 closes the circuitfrom conductor 103 and conductor 104, through low speed winding 31 and return conductor 87. Moreover, since the solenoid 35 is receiving current as before, the plunger 34 holds the transmission assembly at its higher gear ratio and the basket rotates at the lower extraction speed for example, 200 revolutions per minute.
With a dynamic unbalance at either extraction speed, the bracket 59 of the tub actuates the above-described vibration sensing scissors arrangement 60 causing arm 63 to actuate switch button 57 and causing switch blade 53 to break contact with terminals 54 and 56 and to establish contact with terminals 55 and 56. Immediately the circuit through solenoid 35 is broken; this causes plunger 34 to be shifted so as to bring the transmission 21 to its low gear ratio and establishes a circuit to unbalance timer motor 51 causing it to rotate cam 80.
With the rotation of cam 80, the leaf spring 96 flexes to the left, as seen in Fig. 4, releasing pressure upon switch button 96 and causing switch blade 91 to break contact between terminals 92 and 94 and to establish contact between terminals 92 and 93. If the sequence controller 36 is calling only for the lower extraction speed, the shifting of switch blade 91 at this time has no effect on the speed of motor 20 which is now causing tumbling rotation at about 45 revolutions per minute. In contrast, however, when the movement of switch blade 91 occurs while the sequence controller is calling for higher speed centrifugal extraction (the switch 42 at such time bridging contacts 45, 46) a circuit is then established through conductor 98, switch blade 91, terminal 93, conductor 102, conductor 103, conductor 104, centrifugal switch 33, low speed winding 31, return conductor 87 and supply lead 40, i.e., the high speed motor circuit is opened, and the low speed motor circuit is completed. Thus, in the situation where the switch 90 is thus actuated while the motor 20 is already rotating at a speed giving 200 revolutions per minute to the basket with the solenoid 35 energized and 45 revolutions per minute with the solenoid 35 de-energized, the speed of that motor remains unchanged. On the other hand, when the switch 90 is thus actuated while the motor is rotating at a speed giving 300 revolutions per minute to the basket with the solenoid 35 energized, the speed of that motor is promptly reduced to the value which will give only 45 revolutions per minute to the basket with solenoid 35 de-energized. As will be apparent, if the motor speed were not reduced under these conditions, an intermediate speed of about 67 revolutions per minute for the basket would result with the solenoid de-energized. Such a speed would present the danger that the clothes in the basket would not redistribute themselves evenly, and the condition of dynamic unbalance might not be corrected.
As the speed of the basket 9 drops from 300 revolutions per minute to 45 revolutions per minute by the shifting of the transmission assembly to its lower gear ratio, the clothes then have an opportunity to re-orient themselves within the basket at the lower speed. It will be observed that rotation of cam will have caused engagement of the cam with spring 81 to bend it to the right. After the suitable period of operation at 45 revolutions per minute, cam 80 moves over the upper end of leaf spring 81, releasing it and enabling it to snap back to the left to reset 9 unbalance switch 52." When this occurs, terminals 54 and 56 again are bridged and the circuit to the timing motor 51 is broken at which time cam 80 comes to rest holding leaf spring 95 against switch button 96 which in turn resets switch 90.
When switches 52 and 90 are thus reset the circuit through the solenoid 35 is re-established, the solenoid plunger 34 again shifts the transmission to its high gear ratio and the basket is again brought to its extraction speed of either 200 or 300 revolutions per minute, depending on the position of switch 42. If the clothes this time distribute evenly around the basket, the rotation will continue. If, however, the clothes still do not're-distribute evenly, the vibration sensing means again operates and the same steps will occur again.
The speed of rotation of the unbalance timer motor 51 and the arrangement of cam 80 driven thereby with respect to the left springs 81 and 95 are such as to give the necessary time lags between the initial actuating and resetting of the respective switches 52 and 90 to enable the above described operations to take place.
It will be understood that although for the sake of clarity the invention has been described in connection with a transmission providing proper tumbling speed at the low motor speed, it is equally applicable to the opposite situation. For example, the transmission might provide extraction speeds of 300 and 200 revolutions per minute, as before, but with lower speeds of 45 and 30; in such a case, the higher motor speed would be used for tumbling. The switching apparatus described would then be arranged to ensure the higher motor speed upon an unbalance instead of the lower motor speed as was true where the transmission ratio provided 67 and 45 revolutions per minute for high and low motor speed respectively.
While in accordance with the patent statutes, I have shown what at present is considered to be the preferred embodiment of my invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from my invention, and I, therefore, aim, in the appended claims, to cover all such changes and modifications as fall within the true spirit and scope of the invention.
What I claim as new and desire to secure by Letters Patent of the United States is:
1. In a laundry machine, a clothes basket rotatable on a non-vertical axis, a two speed transmission assembly connected to said basket in driving relation thereto, two speed driving means connected to said transmission assembly in driving relation thereto, the higher of said transmission assembly speeds providing extraction speed for said basket with either of said two driving means speeds, the lower of said transmission assembly speeds providing a clothes redistributing tumbling speed for said basket in cooperation with the second of said driving means speeds, electrical control means for controlling said transmission assembly to select either one of said two transmission assembly speeds, an unbalance timer motor, cam means operated by said unbalance timer motor, first switch means controlling said electric control means and said unbalance timer motor operable to first and second positions so that when in said first position said transmission assembly is controlled to drive said basket at the higher speed and said unbalance timer motor is precluded from operating, and when in said second position said transmission assembly is controlled to drive said basket at the lower speed and an energizing circuit is completed to drive said unbalance timer motor, second switch means controlling said driving means operable to first and second positions to control said driving means to provide respectively the first driving means speed and the second driving means speed, sequence control means operative to bypass said second switch means and control said driving means to operate at its second speed at predetermined times regardless of the operation of said second switch means, and vibration responsive means for actuating said first switch means to said second position thereof upon a predetermined magnitude of vibration of said basket thereby to start said unbalance timer motor, said cam means actuating said second switch means to said second position thereof upon operation of said unbalance timer motor, and said cam means actuating said first and second switch means to their respective first positions after a predetermined period thereby to stop said unbalance timer motor.
2. In a laundry machine, a clothes basket rotatable on a non-vertical axis, a two speed transmission assembly connected to said basket in driving relation thereto, two speed driving means connected to said transmission assembly in driving relation thereto, the higher of said transmission assembly speeds providing extraction speeds for said basket with either of two said driving means speeds, the lower of said transmission assembly speeds providing a clothes re-distributing tumbling speed for said basket in cooperation with the second of said driving means speeds, electrical control means for controlling said transmission assembly to select either one of said two transmission assembly speeds, an unbalance timer motor, cam means operated by said unbalance timer motor, first switch means controlling said electrical control means and said unbalance timer motor, said'switch means having a contact arm operable to first and second positions, a member projecting from said switch means engageable with said contact arm thereby to move said contactarm to said second position upon application of external pressure against said projecting member, said transmission assembly being controlled to drive said basket at the higher speed and said unbalance timer motor being precluded from operation when said contact arm is in said first position, said transmission assembly being controlled to drive, said basket at the lower speed and an energizing circuit being completed to drive said unbalance timer motor when said contact arm is in said second position, second switch means controlling said driving means operable to first and second positions to control said driving' means to provide respectively the first driving means speed and the second driving means speed,,sequence control means operative to bypass said second switch means and control said driving means to operate at its second speed at predetermined times regardless of the operation of said second switch means, and vibration responsive means movable against said projecting member to exert pressure thereon to cause said projecting member to move said contact arm to said second position thereof upon a predetermined magnitude of vibration of said basket thereby to start said unbalance timer motor, said cam means actuating said second switch means to said second position thereof upon operation of said unbalance timer motor, said cam means actuating said first switch means contact arm and said second switch means to their respective first positions after a predetenmined period thereby to stop said unbalance timer motor.
3. In a laundry machine, a clothes basket rotatable on a non-vertical axis, a two speed transmission assembly connected to said basket in driving relation thereto, two speed driving means connected to said transmission assembly in driving relation thereto, the higher of said transmission assembly speeds providing extraction speeds for said basket with either of said driving speeds, the lower of said transmission assembly speeds providing a clothes-redistributing tumbling speed for said basket in cooperation with the second of said driving means speeds, electrical control means for controlling said transmission assembly to select either one of said two transmission assembly speeds, an unbalance timer motor, cam means operated by said unbalance timer motor, first switch means controlling said electrical control means and said unbalance timer motor, said switch means having a contact arm operable to first and second positions, first and second alternatively operable projecting members, said first projecting member being arranged to move-said contact arm to said second position upon application of'ex- Iternal-ipre ssure to said first projecting "r'nernber, said'second projecting member being arranged to move said contact arm to said first position thereof upon application of external pressure to said second projecting member, said transmission assembly being controlled 'to drive said basket at the higher speed and said unbalance timer motor being precluded from operation when said contact arm is in said first position, said transmission assembly being controlled to drive said basket at the lower speed and an energizing circuit being completed to drive said unbalance timer motor when said contact arm is in said second position, second switch means controlling said driving means, and having a contact arm operable to first and second positions to control said drivingmean's to :provide respectively the first driving means speed and the second driving means speed, sequence-control means open 'ative to bypass said second switch means and control said driving means to operate at its second speed at predetermined times regardless of the operation of said second switch means, said cam means being arranged to hold said second switch means contact arm in its first position 'prior to actuation of said unbalance timer motor, and vibration responsive means movable against said first projecting member of said-first switch meansto move said first switch means contact arm to said second position thereof upon a predetermined magnitudeof vibration of said basket thereby to start said unbalance timer-motor, said cam means moving said second switch means contact arm to said second position thereof upon operation of said unbalance timer motor, said cam means actuating said second projecting member of said first switch means thereby to move the contact arm thereof to its first position and actuating said second switch means contact arm to its first position after apredetermined period thereby to stop said unbalance timer motor.
4. In a laundry machine, a clothes basket rotatable on anon-vertical axis, a tub structure enclosing and rotatably supporting said basket, a basket drive including a two-speed transmission assembly for drivingsaid basket and a two-speed motor for driving said assembly and having a high speed winding and a low speed winding, the higher of said-transmission assembly speeds providing extraction speeds for said basket with either of said driving speeds, the lower of said transmission assembly speeds-providing a'clothes redistributing tumbling speed for said basket in cooperation with the lower of said motor speeds, a solenoid for shifting said assembly from one "of its speeds to the other and to effect the higher speed thereof while said solenoid is energized, a first circuit for energizing said two-speed motor including the windings thereof and a sequence control having a doublethrow switch movable between a first position for energizing said high speed winding and a second position for energizing said low speed winding, an unbalance timer motor having a cam driven thereby, an unbalance switch movable between a solenoid energizing position and an unbalance timer motor energizing position, a second circuit including said sequence control for energizing said solenoid and said unbalance timer motor independently of each other and having therein a single throw switch, said solenoid, said unbalance switch and said unbalance timer motor, unbalance switch actuating means movable in dependence upon vibration of said tub and serving to position said unbalance switch thereby to energize said solenoid during acceptable vibration of said tub and to energize said unbalance timer motor during non-acceptable vibration of said tub, a speed control switch for said two-speed motor operable by said cam and movable thereby upon energization of said unbalance timer motor to a low speed winding position from a high speed winding position, and a third circuit including said first position of said double throw switch, said speed control switch and said motor windings for energizing said low-speed winding upon deenergization of said solenoid and energization of said unbalance timer motor, whereby said twospeed motor may operate at its lower speed whenever said unbalance switch is operated by vibration of said tub and regardless of the setting of said double throw switch of said sequence control.
5. A laundry machine as defined in claim 4 wherein said unbalance switch includes a switch resetting means operable by said cam and serving to interrupt said second circuit following a time delay sufiicient to permit the clothes in said basket to re-orient themselves during operation of said two-speed motor at its lower speed.
References Cited in the file of this patent UNITED STATES PATENTS
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US2561186 *||Feb 4, 1943||Jul 17, 1951||Gen Electric||Washing machine|
|US2832208 *||Aug 3, 1955||Apr 29, 1958||Gen Electric||Adjustable vibration sensing means for laundry machine|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US3084799 *||Mar 21, 1960||Apr 9, 1963||Maytag Co||Time delay control apparatus|
|US3117926 *||Nov 28, 1958||Jan 14, 1964||Pellerin Corp Milnor||Automatic imbalance control system for a clothes washing machine|
|US3123701 *||Jan 3, 1961||Mar 3, 1964||Parsons Corporation||figure|
|US3152461 *||Jun 30, 1961||Oct 13, 1964||Bill Glover Inc||Automatic laundry machine|
|US3311237 *||May 31, 1966||Mar 28, 1967||Maytag Co||Fluid extractor speed control|
|US3425559 *||Jun 10, 1966||Feb 4, 1969||Gen Motors Corp||Domestic clothes washer having improved speed control means|
|US3583182 *||Oct 20, 1969||Jun 8, 1971||Hitachi Ltd||Washing machine|
|US5280660 *||Oct 5, 1992||Jan 25, 1994||Pellerin Milnor Corporation||Centrifugal extracting machine having balancing system|
|US6422047||May 4, 2000||Jul 23, 2002||Maytag Corporation||Washing machine with unbalance detection and control system|
|US6578225 *||May 24, 2001||Jun 17, 2003||Skf Autobalance Systems Ab||Low-speed prebalancing for washing machines|
|U.S. Classification||68/12.6, 68/23.1, 210/144|