US 3914963 A
A rebound assisted reversing system for a washing machine in which the washing machine may be of the type having a separate tub, agitator, and spin basket or of the type having a tub, agitator, and spin basket constructed as one integral member.
Description (OCR text may contain errors)
United States Patent [191 Brimer Oct. 28, 1975 WASHING MACHINE AND REBOUND ASSISTED REVERSING SYSTEM THEREFOR  Inventor: Claude Morris Brimer, Tucson,
 Assignee: Linear International Corporation,
Rancho La Costa, Calif.
 Filed: July 17, 1974 [211 App]. No.: 489,405
 US. Cl. 68/23.7  Int. Cl. D06F 35/00  Field of Search 68/23.7, 23, 133, 24, 236,
 References Cited UNITED STATES PATENTS 3,153,951 10/1964 Whelan 68/23.7 3,355,914 12/1967 Venena et al 68/23.7
Primary ExaminerRichard E. Aegerter Assistant Examiner-Willis Little Attorney, Agent, or Firm-Lockwood, Dewey, Zickert & Alex [5 7 ABSTRACT and a separate agitator, rigid stops are attached to the spin basket. An elastic rebound member, capable of driving the spin basket during the spin cycle, is attached to the agitator shaft. A reversible motor drives the agitator shaft and during the washing cycle is used to impart an agitational motion to the agitator. The elastic rebound member is aligned so that it strikes the rigid stops which are attached to the spin basket and then rebounds to assist in imparting the agitational motion to the agitator. A motor reversing switch actuates upon contact between the elastic rebound member and the rigid stops attached to the spin basket and thereby substantially limits this contact to the time that the elastic rebound member engages the rigid stops. More than one elastic rebound member can be used and each can have a different degree of elasticity, thereby increasing the number of agitational combinations. During spinning the elastic rebound member drives the tub.
A washing machine equipped with tub, spin basket, and agitator constructed as one integral member, wherein the agitator consists of internal fins or protrusions which are attached to the tub. The drive for the tub consists of a linear motor having a stator and rotor element. The rotor element is externally attached directly to the wall of the tub, and the tub has rigid stops externally attached which are aligned to contact an elastic rebound member which is attached to the case. During washing, an agitational motion is imparted to. the tub when a reversing switch reverses the motor at essentially the same time that the elastic rebound member strikes the rigid stops. The tub rebounds from the elastic rebound member and the motor is thereby assisted in imparting the agitational motion. During spinning the elastic rebound member is repositioned so as to be clear of the rigid stops.
11 Claims, 6 Drawing Figures US. Patent Oct. 28, 1975 Sheet 1 of3 US. Patent- Oct.28, 1975 Sheet3of3 3,914,963
WASHING MACHINE AND REBOUND ASSISTED REVERSING SYSTEM THEREFOR BACKGROUND OF THE INVENTION The field of art to which the invention relates is washing machines for textiles, in'particular to the agitating type with a centrifugal extractor, which may or may not include an independent tub, agitator, and spin basket combination. Specifically, the invention relates to a rebound assisted reversing system for achieving agitation.
The prior washing machine art has disclosed mechanically resonate agitator drive systems in which energy is stored by one of two opposing springs during nonpeak torque conditions and may then be expended in providing a portion of the reversing torque. In such a system the agitator and a rigid cranking member are mounted on a motor shaft. During the wash cycle the rotational direction of the motor is continuously reversed on a periodic or predetermined operating frequency. Almost immediately upon each reversal the rigid crank member deforms one of two opposing springs which are connected to the spin basket. It is apparent that in such a system the agitational motions are primarily dependent upon the timing arrangement by which the motor is reversed. In addition, it can be seen that in such a system one or both of the opposing springs is deformed practically at all times. In such a system neither the position of the springs nor that of the rigid crank arm is simply or easily modified, and therefore, it is extremely difficult to change the agitational characteristics of such a machine without changing the predetermined operating frequency or timing cycle. Further, because such a machine reverses on the basis of this predetermined timing cycle, a sharp change in direction or rebound effect at the time the rotating crank contacts the spring is lost; instead the spring is used to dissipate the energy of contact by serving as a cushion between the crank and the basket. This cushioning results in reduced agitation due to the lower rotational velocity it creates; and for many fabrics this reduced agitation is undesirable. From the maintenance standpoint, the apparatus of the prior art is both difficult to get at and time consuming to repair. The present invention solves these problems by providing: (1) rebound assisted reversing apparatus which is capable of producing a high velocity agitational effect at the time the drive motor reverses; (2) agitational apparatus capable of being easily modified to change the agitational characteristics; (3) agitational apparatus which is not dependent upon a timed cycle for reversing; (4) reversing apparatus which is easily accessible and simple to repair; and (5) agitational apparatus which is not dependent upon a natural or harmonic operating frequency.
US. Pat. No. 3,194,032, dated July 13, 1965, discloses a washing machine and an electromagnetic drive system therefor wherein the motor drive arrangement incorporates the principles of the eddy-current induction type linear actuator. The present invention improves this machine by incorporating the rebound assisted reversing apparatus referred to above.
SUMMARY One major problem in building a washing machine is that the motor is required to accomplish two highly different jobs. First, for washing a high torque is required in order to create a high enough agitation level to do a thorough job of cleaning the clothes. On the other hand for extraction, or spin dry, a high rotational velocity is required in order to achieve the centrifugal force sufficient to remove or extract the water from the clothes. A principal reason that such high torque is required for the washing cycle is that for each reversal of the motor much energy is lost in stopping and then reversing the rotational motion. As is indicated in the background above, a partial solution of this problem by the prior art has been to cushion the stopping force by means of springs and then retain the energy imparted to the springs until the drive motor is reversed. This cushioning effect has the disadvantage of slowing the agitator and thereby reducing the degree of agitation. Further, the direction of rotation of the agitator and the spin basket is the same during any period after the crank compresses the spring and reverses the direction of the basket (untilthe time the motor reverses), and because of this little agitational or washing effect is achieved during such a period. These problems are to a great degree alleviated by the instantaneous strikerebound effect achieved in the present invention. The present invention utilizes an elastic rebound member attached to the motor shaft which drives the agitator. This member strikes and rebounds from rigid stops connected to the basket, and a reversing switch for the motor reverses the direction of the motor at essentially the same time that the member strikes a stop. Thus, practically all periods in which the agitator and the spin basket move in the same direction are eliminated, thereby improving agitation. In addition, the strikerebound effect permits a motor of lower torque to be used while still obtaining high washability and high velocity for extraction. These improvements are of particular importance in the construction of a single disk washer of the type utilizing the motor drive arrangement which incorporates the principle of the linear actuator.
The mechanism used for reversing in the prior art has been relatively unaccessible and difficult to repair. The present invention is simple and easy to get at for repair with both the rebound bar and the rigid stops being easily replaceable. Further, the number of moving parts has been reduced to the minimum. of one; for in the present invention only the rebound member moves, the rigid stops being fixed to the spin basket. In the prior art it is necessary that the rigid cranking member and the springs all move. This elimination of moving parts increases the simplicity by which agitation can be achieved.
In the present washing machine the tub or spin basket has inclined walls with perforations circumferentially arranged near the top. When this spin basket is rotated, the wash water is centrifugally extracted in an upward direction and out through the top perforations. The washing machine case is fitted with a drain connection which allows for gravity removal of the water which has been extracted from the spin basket. However, this drain is sized so that the rate of flow through the drain is less than the maximum flow rate at which water can be extracted from the spin basket. The spin basket is designed with fins on its exterior which come into contact with any extracted water which accumulates in the washer case; and corresponding fins are attached to the case. When the spin basket is loaded and the spin cycle is started, the liquid extraction rate is high. Because at this time the extraction rate is higher than the rate at which the water flows by gravity through the case drain, the extracted water accumulates in the case. The fins on the spin basket come into contact with this accumulated water and this contact serves as a drag or breaking force on the basket. As a result the basket slows down and the extraction rate decreases.
As the rate of extraction decreases the rate of water accumulation in the case decreases; this in turn causes the rate at which the drag or breaking force is increasing to decrease. Because water is being continuously removed through the case drain, the rate of accumulation eventually becomes negative and the rate of extraction then increases. Thus, it can be seen that the rate of extraction is modulated at or around an equilibrium condition as the water is removed from the basket. This equilibrium rotational rate increases through the extraction period, reaching a maximum when most of the water has been extracted, and there is no accumulated water in the case. The fins attached to the inside of the case are for the purpose of stabilizing the water which accumulates in the case. This stabilization prevents the accumulated water from being set into rotational motion by the spin basket and thereby eliminates the reduction in drag which would otherwise occur. This low initial extraction rate results in better distribution of washed articles and improved balance during the subsequent high spin rate.
The conventional washing machine generally has the agitator, tub and spin basket as separate' elements and it is also driven by a conventional motor. As referred to in the background section, U.S. Pat. No. 3,194,032 discloses a washing machine, otherwise conventional, but incorporating a linear motor drive system. However, that washing machine includes the separate washing elements, with their attendant complexities, high manufacturing costs and relatively high maintenance costs. The present invention reduces these problems considerably by providing in such a washing machine an integral agitator, tub and spin basket, constructed in one piece, along with the new rebound assisted reversing apparatus and the wash water extraction rate regulating apparatus.
The principal object of the present invention is to provide a rebound assisted reversing apparatus which provides more agitation for washing machines than is presently obtainable.
Another object of the present invention is to provide a rebound assisted reversing apparatus for washing machines which permits the use of motors with lower torque, and in particular, to provide such apparatus for washing machines driven by drive motors incorporating the principles of the linear actuator.
A further object of this invention is to provide a washing machine wherein agitator. spin basket and tub are a single piece or of integrated construction.
A still further object of this invention is to provide a simplified washing machine in which complexity and cost are reduced while providing greater reliability and less need for maintenance.
Certain other objects will appear hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS For a more complete understanding of the nature and scope of the invention, reference-may be had to the accompanying drawings, wherein:
FIG. 1 is a vertical sectional view through a washing machine having a conventional tub, agitator and spin basket;
FIG. 2 is a horizontal sectional view taken along line 2-2 of FIG. 1;
FIG. 3 is a vertical sectional view through a washing machine in which the tub, spin basket and agitator have been constructed as one unit;
FIG. 4 is a horizontal sectional view taken along line 44 of FIG. 3;
FIG. 5 is an electrical circuit diagram for the washing machine of the invention; and
FIG. 6 is a horizontal cross-sectional view similar to FIG. 4 showing two modifications of the stops which may engage the rebound bar.
Description of the Preferred Embodiments The present invention relates in particular to the rebound assisted reversing apparatus and its related components in a washing machine. Since the remaining parts of a washing machine, such as pumps, hoses, supports, cover, etc., are conventional and generally Widely known in the washing machine field, and since their exact nature or type is not necessary for an understanding and use of the invention by a person skilled in the art, they will not be described in detail.
Referring to FIGS. 1 and 2, a washing machine case 10 houses tub l1 and an agitator 12 is attached to and supported by hollow shaft 13. Cap 14 is screwed onto shaft 13 and keeps agitator l2 firmly in place. Shaft 13 is journaled in bearing 15 which also provides a watertight seal between shaft 13 and tub 11. Spin basket 16 is constructed with a shaft or sleeve support 17 having a shoulder 18 which rides on bearing 20 which in turn is supported by shaft 13. Lateral support for basket 16 and co-axial alignment for concentric shafts l3 and 17 is provided by top bearing 21 and bottom bearing 22. Drain 41 provides for removal of water from tub 11. Bracket 23 is attached to the bottom of tub 11 and supports stator element 24 for a linear motor. Rotor 27, which with stator 24 comprises the linear motor, is supported by bracket 26 which is in turn attached to shaft 13.
Magnetically biased magnetic reed switch 42 is mounted to the case 10 by means of bracket 43 in such a position that it is clear of magnets 44 and which are mounted on rotor 27, but so that they come in close proximity as the rotor rotates. The magnets 44 and 45 are mounted so that the north pole of one is up and the south pole of the other is up. As the rotor 27 rotates in a counterclockwise direction magnet 44 approaches reed switch 42 causing it to reverse the driving action of the motor, at substantially the same time rebound bar 31 strikes stop 33 quickly stopping the direction of rotation and causing a rebound motion in the opposite direction. Reed switch 42 will remain in this position, causing the motor to drive in a clockwise direction until magnet 45 approaches the reed switch at which time another reversal takes place.
A collar 30 is keyed to shaft 13 in the conventional manner so that they rotate together. The elastic rebound bar 31 is constructed from flexible steel or other flexible material, attached to collar 30, and is aligned to strike rigid stops 32 and 33, when the spin basket shaft or sleeve 17 and the agitator shaft 13 are moved relative to each other. While in this preferred embodiment the rebound member is shown as a bar it will be recognized that other arrangements could be used, i.e., member 31 could be ridged and a resilient pad or compression spring could be mounted on stops 32 and 33. It can be seen that there is no physical connection between the agitator shaft 13 and the spin basket 16 and that the elastic rebound bar 31 moves freely between stops 32 and 33, being positioned so that during the wash cycle physical contact between it and the stops 32 and 33 is limited substantially to the time of striking.
The elastic rebound bar 31, while having sufficient flexibility or elasticity to rebound from stops 32 or 33 during washing, is of sufficient strength and rigidity to be capable of driving spin basket 16 during the spin cycle. During the spin cycle the reversing switch is deactivated and the motor does not reverse when rebound bar 31 strikes stop 32 or 33. Instead rebound bar 31, after initial flexing, quickly settles on stop 32 or 33 and drives spin basket 16 during the spin or high speed extraction cycle.
In the operation just described, spin basket 16 was free to rotate at will during the wash or agitation cycle. A solenoid operated brake, generally at 50, is provided to hold spin basket 16 in place during the wash cycle if desired. Bracket 51 mounts brake 50 to tub 11, and shaft 52 extends through tub I 1 with water-tight seal 53 preventing leakage. Stop 54 engages basket recess 55 at the beginning of the agitation cycle and holds spin basket 16 in place. During the spin cycle solenoid 50 withdraws stop 54 from recess 55 and the spin basket 16 is free to rotate.
The individual positions of stops 32 and 33 may be changed to provide differing angular distances for the rebound bar 31 to travel. In addition, more than one rebound bar 31 may be used and each may be of a differing degree of elasticity. These easily made modifications, coupled with the ability to operate with the basket either locked or free to rotate, provide for a wide variety of agitational combinations. The result is a washing machine which can accommodate fabrics of all types while still providing the high degree of washability obtainable through the instantaneous strikebound method of agitation.
Referring now to FIGS. 3 and 4, a novel washing machine is shown. The case 70 has a bottom 72 which rotatably supports tub 71 in recess 81 on a bearing surface 73 which is preferably teflon or other material commercially available to provide a surface with a low coefficient of friction. It will be understood that tub 71 also may be supported in a more conventional manner than illustrated. Side fins 74 and bottom fins 76 are integrally attached or formed on the inside of tub 71 to provide agitation for the contents of the tub 71.
Rotor element 77 and stator 78 comprise a linear motor with the stator 78 being supported by bracket 80 from case 70 while the rotor 77 is attached to, and thereby drives tub 71.
Rigid stops 82, 83, 84 and 85 are constructed from steel or other suitable material and attached to the outside of the tub 71. A curved elastic rebound bar 90 constructed of steel or other suitably elastic or flexible material and is adjustably attached to case 70 by brackets 92, 91 and 93. The upper end 94 of rebound bar 90 is horizontally positioned in bracket 93 to limit rotation about vertical axis 100. The lower end 101 of rebound bar 90 is horizontally positioned so as to be capable of striking stops 82, 83, 84 or 85 when tub 71 rotates. Solenoid or actuator 95 actuates operating arm 98 which raises or-lowers collar, 96 upon which rebound bar pin 97 rides. Pin. 97 is loosely attached to rebound bar and through this arrangement actuator raises and lowers rebound bar90; the result being that rebound bar ,90 is positioned to strike one or more of stops 82, 83, 84 and 85 during washing and then repositioned to be clear of these rotating stops 82, 83, 84 and 85 during the spin cycle. Further, it will be understood the number of different additional combinations can be increased by the addition of another or more rebound bars. These additional rebound bars can have differing degrees of elasticity to even further increase the number of agitational combinations.
Magnetically biased magnetic reed switch 99 is mounted in a position so that magnets 107 and 108 come in close proximity to it as tub 71 rotates. Magnets 107 and 108 are attached to tub 71 so that the north magnetic pole of 107 and the south magnetic pole of 108 are presented to reed switch 99. As the tub 71 rotates in a clockwise direction magnet 107 approaches reed switch 99 causing it to reverse the driving direction of the motor. At substantially the same time stop 83 strikes rebound bar 101 quickly stopping clockwise rotation and causing a rebound motion in a counterclockwise direction. Tub 71 will continue to be driven in the new direction until magnet 108 approaches reed switch 99 and another reversal takes place. It will be understood that by positioning rebound bar 101 so that it does not strike any of stops 82, 83, 84, or 85 that the motor alone will cause reversal of tub 71 causing a much more gentle washing action which may be desirable for laundering very delicate fabrics.
While I have described an embodiment where the rebound bar 90 is adjustably attached to the case and the rigid stops 82, 83, 84 and 85 are attached to the tub, it will be understood that the position of the rebound bar and the stops can be reversed. Thus, the elastic rebound bar may be attached to the tub 71 with the rigid stops being attached to the case 70, either being adjustably attached, so that the combination is aligned to strike each other during washing and capable of being positioned so as to be clear of each other during spinning. It can again be seen that during the wash cycle they are positioned so that physical contact between them is limited substantially to the period between the time they strike each other and the time the tub rebounds. It will also be understood that other means than a bar may be employed to obtain the rebound effect.
Tub or basket 71 is constructed with a bottom piece 104 and an inclined side wall 102 which is substantially concentric about its rotation axis 103. Whereas the conventional spin basket has perforate walls, spin basket 71 is limited to perforations 77 circumferentially arranged near the top edge 105 of the side wall 102. The side wall 102 is inclined down and toward the center of basket 71 so that upon spinning any liquid in the basket 71 is centrifugally extracted in an upward direction and out through the perforations 77.
The case 70 comprises sides 106 and bottom 72. The bottom 72 is fitted with liquid drain 88 which is sized to allow gravity removal of liquid from case 70 at a lower flow rate than the' maximum flow rate at which liquid in the spin basket or vessel 71 is centrifugally extracted through perforations 77. Thus, when basket 71 is loaded and the spin cycle is started, the initial flow of water extracted from basket 71 is greater than the gravity flow through drain 88', and the result is an accumulation of water in case 70. Fins 86, which' are attached to the outer surface of tub 71, serve as a break 1 or slowing apparatus by coming into contact with this accumulated water and. creating a drag. Thefins 86' mayvset the accumulated water in a similar rotational motion thereby reducing the drag or frictional effect between the fins 86 and the accumulated water. This is undesirable and therefore fins 87 are attachedflto the inner surface of the case bottom 72 so as to provide a stabilizing effect on any liquid accumulated in the case.
An electrical circuit appropriate for use in the rebound assisted reversing system is shown in FIG. 5. The magnetically biased magnetic reed switch 99 utilized in this circuit comprises a bi-stable magnetically biased switch, such as a Gordos (Trademark) model MR 200-2. The reed 99a of switch 99 is caused to switch into one or the other of its positions by primary biasing means in the form of magnets 107 and 108 mounted on the tub 71 (FIG. 4). These magnets move the reed 99a back and forth against contacts 99b and 990 as the tub reciprocates, alternatively closing the circuits associated with these contacts. A secondary biasing means in the form of a magnet 99m, acts to maintain the reed 99a in position once the contact is closed until the force of the primary biasing means subsequently switches the reed to the opposite contact.
It will be understood that other switching means can be utilized to produce the same result without depreciating from the scope of the invention. For instance, a simple dual contact magnetic reed switch along with a resetset (RS) flip-flop circuit and appropriate signal conditioners, such as Schmitt triggers (not shown) may produce the same results. The remaining portion of the illustrated control circuit is shown at 110 and includes a gate controlled semiconductor switching means 111 for each circuit, such as is commonly manufactured by General Electric under the trademark TRlAC, and a current limiting resistor at 112. A reversible electric motor, which may be conventional in design and construction, is shown in the circuit at 113 and an alternating current power source is connected across terminals A-B to complete the circuit.
' In FIG. 6, two examples of alternately structured stop equivalents are shown as mounted on a tub 115 and engage rebound bar 116 both similar respectively to tub 71 and rebound bar 90 described previously. The stop 120 includes a coil spring 121 attached thereto and stop 122 includes a rubber bumper 123 at their leading sides, both of which lessen the impact of an abrupt engagement of the respective stop and the rebound bar 1 l6.
lt will be understood that modifications and variations may be effected without departing from the scope of the novel concepts of the present invention, but it is understood that this application is limited only by the scope of the appen'ded claims.
1. An improved washing machine of the type having a casing including clothes receiving means mounted for rotatable and oscillatory' movement, a reversible motor, and means drivably connecting the motor to said clothes receiving means, wherein the improvement comprises:
a. stopping means rigidly attached to one of said casing and clothes receiving means;
' c". switching means for reversing the driving direction b. elastic rebound means carried by the other of said casing and clothes receiving means and aligned to strike said stopping means at least during oscillatory movement of said clothes receiving means;
- and 1 in which said clothes receiving means includes internal agitator means fixedly attached thereto and a side wall which is inclined upwardly and outwardly relative to a central axis thereof, perforations circumferentially arranged near the top edge of the side wall of said clothes receiving'means, drag means attached to the outer surface of said clothes receiving means located so as to create a dragging action within liquid which accumulates in said casing, fin means mounted in the casing to provide a stabilizing effect on any liquid accumulated therein, and liquid draining means in said casing of a size to allow removal of liquid from said casing at a lower flow rate than the maximum flow rate at which liquid is centrifically extracted through said perforations of said clothes receiving means.
5. An improved washing machine of the type having a rotatable spin basket and aseparate washing agitator with the shafts of each being concentric and a linear motor having at least one stator and at least one moving rotor element with the rotor element being connected to the agitator shaft, wherein the improvement comprises:
a. stopping means rigidly attached to the spin basket; b. elastic rebound means, capable of driving the spin basket during the spin cycle, attached tothe agitator shaft, aligned to strike said stopping means when the spin basket and the agitator are rotated relative to each other, and positioned so that during the wash cycle physical contact with said stopping means is limited substantially to the time of striking said stopping means by said elastic rebound means; and 0. switching means for reversing the driving direction of the motor at essentially the same time during the wash cycle that 'said elastic rebound means strikes said stopping means. 6. An improved washing machine as recited in claim 5 in which a. the elastic rebound means is a flexible bar; and
b. the stopping means is a resilient member.
7. A washing machine comprising:
a. a tub having a side wall substantially concentric about an axis, a bottom, and internal agitator means fixedly attached;
b. a reversible motor drivably connected to rotate said tub; I c. a case, having sides and a bottom, in which said tub is rotatably supported;
(1. means for reversing the direction of the tub during washing attached both to said tub and to said case and comprising rigidly mounted stopping means and elastic rebound means, said elastic rebound means and said stopping means being aligned to strike each other during washing, capable of being positioned so as to be clear of each other during spinning, and positioned so that during the wash cycle physical contact between them is limited substantially to the period between the time they strike each other and the time that said tub rebounds; and
e. switching means for reversing the driving direction of said motor at essentially the same time during the wash cycle that said elastic rebound means strikes said stopping means.
8. A washing machine as recited in claim 7 further comprising:
a. perforations circumferentially arranged near the top edge of the side wall of the tub;
b. the side wall of the tub being inclined down and toward the center so that upon spinning any liquid in the tub is centrifugally extracted in an upward direction and out through said perforations;
c. liquid drain means in the case, said drain means being sized to allow removal of liquid from the case at a lower flow rate than the maximum flow rate at which liquid in the tub is centrifugally extracted through said perforations;
d. drag means attached to the outer surface of the tub located so as to create a dragging action with any liquid which accumulates in the case, the dragging action between said drag means and any accumulated liquid providing a braking force to the tub; and
e. fin means attached to the inner surface of the case so as to provide a stabilizing effect on any liquid accumulated in the .case.
9. A washing machine as recited in claim 8 in which the motor is a linear motor having at least one stator and at least one moving rotor element means, said rotor element means being attached to the tub.
10. A washing machine as recited in claim 7 in which the elastic rebound means is adjustably attached to the case and the rigidly mounted stopping means is attached to the tub.
1 l. A washing machine as recited in claim 7 in which a. the elastic rebound means is a flexible bar; and
b. the stopping means is a resilient member.
UNITED STATES PATENT AND TRADEMARK OFFICE CETIICATE OF CORREQTIQN PATENT NO. 2 3,914,963 I DATED October 28, 1975 INV ENTOR(S) I CLAUDE MORRIS BRIMER It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:
In column 3, line 62 after "objects" please insert -will be obvious and- Sugned and Sealed this Twenty-seventh Day Of July 1976 [SEAL] A ttes t:
RUTH C. MASON C. MARSHALL DANN Arresting Officer Commissioner ofParents and Trademarks