US 3051313 A
Description (OCR text may contain errors)
1962 D. E. STELLI 3,051,313
CONTROL MECHANISM Filed Aug. 26, 1959 3 Sheets-Sheet 1 INVENTOR. Dan/kl E. Ste/l1- tat The present invention relates to control mechanisms and more particularly to such mechanisms as utilized in machines in which a rotation or centrifuging is performed.
This invention while not strictly limited thereto, has been designed for use on clothes washing machines in which there is usually provided an automatically programmed cycle including all the steps necessary for the completion of an entire washing operation. Generally these steps include at least one step in which the wash tub or basket containing clothes is rotated at a relatively high speed to centrifugally extract the washing or rinsing liquid. It is generally known that during this rotation, the contents of the basket quite frequently tend to agglomerate in some portion of the basket, thus unbalancing the basket load. This unbalance causes the basket to gyrate erratically about the normal rotative axis. The degree or amount of gyration is naturally dependent on the amount of unbalance of the load. When the gyrations become excessive, the effect is manifold. First, the basket may strike the enveloping structure, with possible damage to both. Also, the entire machine tends to vibrate and shake. Further, the audible effects of these reactions frequently reach undesirable intensity.
Further, once the load has become unbalanced, it does not of itself become balanced; but instead, as a corrective measure the rotative speed of the machine must either be reduced materially or halted altogether to allow resolution of the unbalanced condition. It is to the latter, i.e., the complete stoppage of rotation that the present invention applies.
It is, therefore, the principal object of the invention to provide a simplified form of mechanism for interrupting the excessive gyration of a rotating receptacle.
It is a further object to provide a device utilizing two independently actuated lever arms each acting upon a separate switch-governing member to efiect bi-stable operation of a two-sided limit and reset switch.
Other objects, features and advantages of the invention will be apparent from the detailed description of a presently preferred embodiment thereof, read in connection with the accompanying drawings in which:
FIGURE 1 shows partially sectioned side view of a clothes washing machine.
FIGURE 2 shows a sectional side view of the shut-off switch mechanism, taken on lines 22 of FIGURE 3.
FIGURE 3 is a sectional view taken through the lines 3-3 of FIGURE 2.
FIGURE 4 is a partially sectioned plan View taken along the lines 4--4 of FIGURE 2.
FIGURES 5, 6 and 7 are views in detail of components of the assembly of FIGURE 2. The components shown are the switch support bracket (top view) in FIGURE 5, the bumper actuated lever arm (side view) in FIGURE 6 and the reset lever arm (rear View) FIGURE 7.
FIGURE 8 is a simplified schematic drawing of the connection of the shut-ofi switch into the electrical control circuit.
FIGURE 9 shows an alternate embodiment of the switch sub-assembly.
in FIGURE 1 is shown an agitator type clothes Washing machine 10 having a clothes basket 11 in turn disposed within an outer imperforate tub or inner casing 12. The tub 12 is mounted within an appearance cabinet 13 which includes a hinged cover 14 for providing access to the clothes basket. The basket which is generally frustoconical in shape has an open face adjacent to the access opening to provide access to the basket interior. About the periphery of the basket adjacent the open face is an annular balance ring 15 of high density material providing a comparatively large moment of inertia for the basket. At the center of the basket there is positioned a vertical axis agitator 16 which includes a center post 17 and a plurality of radially extending vanes 18. The agitator is further provided with an outwardly and downwardly flared skirt 19 to which the vanes 18 are joined at their lower ends.
Both the clothes basket 11 and the agitator 16 are rotatably mounted. The basket is mounted on a rotatable hub 21? and the agitator 16 is mounted on a shaft 21 which extends upwardly through the hub 20 and the center post 17. The agitator is secured to the shaft by any suitable means (not shown). During the cycle of operation of the machine 11} the agitator is first oscillated back and forth within the basket 11 to wash the clothes therein. Then, after a predetermined period of this washing action, the basket 11 is rotated at high speed to extract centrifugally the washing liquid and discharge it into the outer tub 12 largely through horizontal line of apertures 11.-1. Following this extraction operation, a supply of clean liquid is introduced into the wash basket for rinsing the clothes, and the agitator is again oscillated. Finally, the basket is once more rotated at high speed to extract the rinse water and discharge it into the outer tub.
The basket 11 and agitator 16 may be driven by any suitable means as the drive means designated box 22 which forms no part of the present invention. The basket 11 is mounted resiliently to the rotatable hub 20 so that the path of travel of the outer periphery of the basket may be orbital or at least non-uniform. If the load consisting of clothes and wash liquid is properly balanced within the basket, then the peripheral path of travel will approximate that of a regular circle. With degrees of unbalance, the basket peripheral path will tend to depart more from that of a regular circle and is described most readily by the term gyratory. When the load has exceeded the maximum degree of unbalance allowable, which degree would cause damage to the machine, it is described herein as excessively gyratory.
The structure 23 which is primarily responsive to the excessive gyration of the tub is molded from a resilient, elastic material such as rubber. It comprises an enlarged head 24 with its innermost extremity contact surface 24.1; the head having been formed at the end of a reduced diameter neck 25. Said neck extends inwardly toward the tub 12 from an enlarged body shell 26, fixed, as by the opposed flanges 2.7 to the tub 12. It will be understood that the tub wall has an approximate opening within which the structure 23 is mounted. I consider the body shell 26 to be that portion of the structure surrounding the neck 25; and as a matter of practical operation, the body portion is immovable relative to the tub 12. The cylindrical element 28 comprises an integral extension of the neck 25. When the head 24 is displaced to the right of FIGURE 2 in response to excessive gyration of the basket, as later described, the effect is to axially displace the neck and the element 28 relative to the body shell 26. This movement may be likened to an extrusion relative tothe body portion, from which the structure recovers and returns to original condition. To protect the relatively soft contact surface 24.1 from damage, I prefer to interpose a guard structure 29 embodying a sheet of nylon or other tough, resilient material between the head 24 and the basket 11.
Mounted outwardly of the inner casing 12, at an area above that of the bumper, is switch support structure 31 which is in the main a flat plate bed section 32 and a twice upturned flange 33. This support is best shown in FIGURE 2 in the assembly and in FIGURE 5 which is a top view of structure 31 alone.
Strengthening webs 34 have been provided in the support structure to brace the flanges and stabilize the support structure. The bed portion 32 has a substantially square cutout 35, and has two holes 36 to accommodate means for mounting a switch and lever arm sub-assembly. At its uppermost flange, the support is mounted by means of screws 38 extending through the wall of tub 12.
The switch and lever arm sub-assembly includes a snap switch 44 mounted below the switch support structure 31. The switch 40, best shown in FIGURES 2 and 3, in a miniature snap switch having opposed switch actuating members 41 and 42 in the form of buttons extending from its back and front faces, respectively. When member 41 is depressed, the switch is snapped off and member 42 assumes a stable position extending further out of the switch. When button 42 is depressed, the switch is snapped on and button 41 assumes a stable position extending further out of the switch. The switch has at either of its side extremities, the terminals 43 and 44, which serve to connect the switch in series in the control circuit. Thus the switch as used is a single-pole double-throw miniature snap switch which is actuated from opposite sides or faces.
Below the switch is mounted the switch undercarriage structure 45 in the form of a U bracket with outwardly extending arms 46 for mounting to the switch and support structure 31. By means of screws 47 extending through suitable holes in switch 40 and received within the holes 36 in bed 32, the support structure, switch and switch undercarriage are readily assembled into a unit by the use of two screws.
The undercarriage is provided with two bearings 49 and 43 in the form of rivets or the like extending through the respective legs of the U portion. Each of these hearings is used to pivot thereabout a switch-actuating lever arm. The first of these lever arms is the shutoff or bumper arm 50 shown best in FIGURES 2 and 6. This lever arm includes a main channel section, from the sides of which extend symmetrical mounting lugs 51. These lugs as shown fit outside the legs of U-shaped undercarriage 45 and utilize rivet 49 as a hearing about which the lever arm can pivot. The lever arm 50 has at its lower portion a reinforcement 52 in the area of contact with body 28 of the bumper. At its upper extremity lever arm 50 has an extending reinforcement 53 which seats the actuate screw 53.1. .This actuate screw can be seen in FIGURE 2 to bear against switch actuate member 42. This screw provides means for adjusting the amount of lever arm travel to the amount required for proper operation of the switch 40.
Also pivoted about undercarriage 45 is the reset switch follower arm 54 shown in FIGURES 2 and 3. This follower arm is in the form of a lever with extending lugs 55 which mount about the undercarriage 45 at rivet bearing 48. Arm 54 is generally channel shaped and has a trapezoidal shaped reinforcement 56 Within the channel and positioned adjacent actuating switch actuate button 42. The follower arm extends upwardly from its pivot mounting through cutout 35 so that its upper edge extends well above the switch. The possible pivotal movement of follower arm 54 is thereby restricted to an arc encompassing only a few degrees.
A reset mechanism 57 is positioned externally of the cabinet 13 beneath the upstanding ba'cksplasher and control panel 58. This reset mechanism includes an actuate button 59 and permanently secured to it a horizontally extending rigid rod or body. The body is guided for axial movement within suitable apertures 61 in the channel mounting bracket 62. This bracket is solidly aflixed to the bottom of the control panel by means such as screws 62.1 shown. Permanently afiixed to the rear end of body 60 is rigid slide arm 63 which extends downwardly so that its lower portion is disposed adjacent the upper portion of follower lever 54. The actuate button 59 of the reset mechanism is spring loaded to return to its normal position by means of spring 64 coiled about reset rod body 60 and compressed between the rear of the button and the front leg of bracket 62.
The operation of the shut-off mechanism is as follows:
When the on-ofl switch 65, shown representatively in FIGURE 7, is turned to the On position and control equipment 66 is set for the proper cycling, the machine it) begins its wash and rinse cycle. At the conclusion of each of said cycles the basket is spun at a high speed to centrifugally extract the wash or the rinse water from the clothes. If dining one of these spin cycles the load in the basket is unbalanced, the basket will gyrate erratically. In an extreme condition, the basket may gyrate excessively, whereupon the balance ring 15 will strike strongly against the section of the guard member 29 protecting the head 24 of structure 23. Said structure, due to its resiliency, will transmit this striking force from its contacted surface 24.1 through to the element 28 producing an axial displacement; whereupon element 28 will then strike reinforcement 52 pivoting lever arm in a counter-clockwise direction. Adjusting screw 53.1 will strike actuate button 41 which in turn opens switch 40 from the position shown in FIGURE 7. Depression of button 41 pushes button 42 to extend further from the switch. The switch then remains in this stable off condition. The circuit to control equipment 66 thereby opens and remains open, shutting off the machine entirely.
When the shut-oft has operated, the operator then will check the machine and seeing that the control equipment (not shown) has not returned to the normal condition will realize that the machine has been stopped in mid-cycle. At this time, the operator should attempt to even the load out in the basket. Once the load has been evenly distributed and the hinged cover 14- closed, the reset button 59 should be depressed. Depression of button 59 compresses spring 64 against bracket 62. The body and extension arm 63 are jointly moved to the right. The lower section of extension 63 strikes the upper portion of reset lever arm 54. As lever 54 is struck, it pivots about bearing 48 and its reinforced mid-section 56 strikes switch actuate button 42 reclosing the circuit to the control equipment. When switch actuate button 42 is so depressed, the button 41 on the opposing side will be extended outward to a position adjacent to bumper actuate lever arm 50. The control equipment will then re-start the washing machine at the place in the cycle where it was shut off, the switch 40 remaining in the closed position until tripped again by excessive gyration.
In FIGURE 9 is shown a second embodiment of the switch sub-assembly as applied to the present invention. In this second embodiment, the majority of the components and the operation of the mechanism are identical to the components described previously. The only components changed are the lever arms '50 and 54 and undercarriage structure 45. In the second embodiment, the bumper actuated lever arm 70 is fabricated of a suitable rigid material such as sheet steel and has a pair of extending ears 71 for rotation about hinge pin 72. Lever arm 70 has a lower extent adjacent bumper extension 28 and an upper extent adjacent actuate button 41. The operation of this lever is identical in operation to that of lever arm 50. Hinge pin 72 is secured through both legs of inverted U bracket 73. Bracket 73 at its cross-portion is seured through follower arm 74 and switch 40 to switch support structure 31 by means of suitable screw 75 and nut 7 6 fastening. Follower arm 74 is fabricated of a resilient material having spring-like qualities and is shaped to provide a downward extending, flexure loop, a central portion extending past actuate button 42 and through cutout 35 to terminate in an angled end portion deflectably adjacent reset extension 63. When reset buton 59. is depressed, extension 63 deflects follower 74 which then flexes and deflects about its flexure loop to depress button 42. All
other phases of the operation of the second embodiment are identical to those described for the first embodiment.
While there has been described what is at present considered to be the preferred embodiment of the invention, it will be understood that various modifications may be made therein, and it is intended to cover in the appended claims all such modifications as fall within the true spirit and scope of the invention.
What is claimed is:
1. In an automatic clothes washing machine having an outer cabinet, a stationary tub mounted within said cabinet, a washing receptacle journalled for gyratory rotation within said tub, and circuit means for controlling the rotation of said receptacle; means for disenabling said circuit on excessively gyratory rotation of said receptacle, comprising a resilient unitary member with a resilient, yieldable knob extending into said tub in an area where said knob is normally positioned so that it will be struck by said receptacle on excessive gyration thereof, said member including a resilient shaft protruding from the knob through said tub, said member further including elements circumjacent said shaft for resiliently securing said memher to said tub for linear motion transmission through said tub, said shaft resiliently constructed to deflect and return to its normal position after having been struck by said receptacle, said shaft responsive only to said knob having been struck a substantial blow by said receptacle for transmitting motion therethrough axially along said resilient shaft, and switch means responsive to said axial motion transmission by said shaft for disenabling said circuit control means for thereby stopping the rotation of said receptacle.
2. In a machine as claimed in claim 1, said resilient knob of comparatively large mass as compared to the area of said resilient shaft whereby said knob absorbs within itself strikings by said recptacle amounting to less than a substantial blow without transmitting said striking motion to said shaft.
3. In an automatic clothes washing machine having an outer cabinet, a stationary tub mounted within said cabinet, a receptacle adapted to receive clothes and washing liquid and having apertures about its upper peripheral portion, means for mounting said receptacle for gyratory rotation within said tub, mechanism for elfecting said rotation for centrifugal expulsion of said washing liquid through said apertures into said tub, electric circuit means for energizing said mechanism, an electric switch in said circuit mounted externally of said tub, and a lever for operating said switch to open circuit position; means for actuating said lever to de-energize said circuit only in the circumstance of excessive gyration of said receptacle, comprising an integral structure of resilient material extending through a wall of said tub in the zone of liquid expulsion, said structure having axially spaced annular flange members snugly receiving said tub wall therebetween, an elongated cylindrical body portion substantially smaller in diameter than said flange members extending axially therefrom into proximity with a free end of said lever, and a head portion at the opposite end of said body, said head portion being disposed within said tub to be struck by said receptacle during gyratory rotation thereof, said head portion being separated from an adjacent flange by a short flexible neck of substantially smaller diameter, whereby under glancing blows said head will deflect without transmitting suflicient force to said body to cause displacement thereof to rotate said lever, while transmitting such force to said body portion in the circumstance of a direct blow from said receptacle.
References Cited in the file of this patent UNITED STATES PATENTS 2,624,464 Morrison J an. 6, 1953 2,807,952 Bochan et al Oct. 1, 1957 2,878,937 Worst Mar. 24, 1959 2,895,023 Blum July 14, 1959