US3584482A

US3584482A - Clothes washer having an oscillating and spinning drive mechanism

Info

Publication number: US3584482A
Application number: US798298A
Authority: US
Inventors: Bryron L Brucken
Original assignee: General Motors Corp
Current assignee: Motors Liquidation Co
Priority date: 1969-02-11
Filing date: 1969-02-11
Publication date: 1971-06-15
Anticipated expiration: 1988-06-15
Also published as: BR7016662D0; CA924119A

Abstract

In the preferred form, a drive mechanism for a washing machine having an integral spin tub and agitator, wherein a reversible motor is utilized to rotate a driven spin roller through a friction drive and to oscillate a slider crank drum through an improved slider crank drive, and wherein a clutch mechanism is utilized upon the direction of rotation of the reversible motor to selectively impart to the integral spin tub and agitator the oscillatory motion of the slider crank drum during a washing cycle and the rotary motion of the driven spin roller during a spin cycle.

Description

United States Patent [72] Inventor Bryron L. Brucken Dayton, Ohio [211 App]. No. 798,298 [22] Filed Feb.11,l969 [45] Patented June 15,1971 [73] Assignee General Motors Corporation Detroit, Mich.

[541 CLOTHES WASHER HAVING AN OSCILLATING AND SPINNING DRIVE MECHANISM 1 Claim, 9 Drawing Figs.

[52] US. Cl 68/23 [51] Int. Cl D06f 23/04 [50] Field of Search ..68/23. 23.3, 23.6, 23.7; 74/82 [56] References Cited UNITED STATES PATENTS 1,696,718 12/1928 Kuhmann et al 68/237 i l i i t i g :6 g V i 2,634,615 4/1953 74/82 2,810,295 10/1957 74/82 2,930,216 3/1960 68/23 X 3,087,321 4/1963 Brucken 68/23.6

Prima'ry Examiner-William 1. Price Attorneys-Warren E. Finken and Frederick M. Ritchie PATENTEU JUN 1 5 I97! SHEET 3 BF 4 PATENTEI] JUN] 519m SHEET 4 OF 4 agmm A T T02 NE Y CLOTHES WASHER HAVING AN OSCILLATING AND SPINNING DRIVE MECHANISM This invention relates to a domestic appliance and, more particularly, to an improved oscillating and spinning drive mechanism for a clothes washer.

In the clothes washing art, agitating and spinning mechanisms have become quite complex requiring the utilization of many parts and in many cases requiring a bulky lubrication system. As the number of parts increase, there is often a proportionate increase in weight, space requirements, and cost. It is, therefore, an object of this invention to provide a simplified oscillating and spinning drive mechanism which will require fewer parts, eliminate the critical need for lubrication, and provide a savings in cost, weight, and space requirements. In the washing machine art, a reduction in weight and space requirements provides the potential of either an increase in load capacity or decrease in unit size.

Accordingly, it is an object of this invention to provide an oscillating and spinning drive mechanism for a washing apparatus of the dry-running type broadly taught in my U.S. Pat. No. 3,087,321, granted Apr. 30, 1963.

In the washing machine art, by integrally molding an agitator with a spin tub it is possible to obtain an extremely lightweight unit in the order of 4 pounds when empty. The resultant weight saving makes it possible to consolidate the drives for agitate and spin. It is, therefore, an object of this invention to provide a simplified oscillating and spinning drive mechanism to selectively impart to an integral agitator and spin tub an oscillatory agitating motionfor washing and a rotary motion for spin drying.

In keeping with the simplified oscillating and spinning drive mechanism, it is an object of this invention to provide a friction roller rotary drive and an automatically adjusted slider crank oscillatory drive, both of which drives can be imparted to a single output drive shaft.

Another object of this invention, is the provision of a simplified clutch mechanism which, dependent upon the direction of rotation of the reversible motor, selectively engages either the oscillatory drive or the rotary drive to impart the selected motion to the tub drive shaft.

It is a further object of this invention to provide an im proved self-retracting roller in the friction roller rotary drive to decrease scuffu'ig wear during the washing cycle.

An advantage of this invention lies in the fact that manufacturing tolerances are less critical than those in other washing machine drive mechanisms.

Another advantage of this invention lies in the economy of design wherein fewer components are required which results in cost savings, a weight savings, and a space requirement savings.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein preferred embodiments of the present invention are clearly shown.

IN THE DRAWINGS:

FIG. 1 is a vertical elevation with parts broken away of a clothes washer provided with the dry running oscillating and spinning drive mechanism of this invention.

FIG. 2 is a vertical elevation with parts broken away of the oscillating and spinning drive mechanism.

FIG. 3 is a bottom plan view taken along line 3-3 of FIG. 2 to show the oscillating and spinning drive mechanism with the slider crank arm in a plurality of operating positions.

FIG. 4 is a fragmentary isometric view of the oscillating and spinning drive mechanism of this invention.

FIG. 5 is a vertical sectional view of a clutch mechanism utilized in the oscillating and spinning drive mechanism of this invention.

FIG. 6 is an exploded perspective view of the clutch members of the clutch mechanism with parts removed to show the clutch-actuating cam surfaces in the preferred form of the invention.

FIG. 7 is a sectional view of the intermediate pulley belttensioning device.

FIG. 8 is a bottom plan view of the slider crank and slider crank drum with the clutch removed.

FIG. 9 is a sectional view of the roller retraction device shown in FIG. 3.

GENERAL In accordance with this invention and with reference to FIG. I, a clothes washer 2 is shown having an outer tub or water container 4. The outer tub 4 is mounted on a suspension system having a support plate 6 which :is located by a plurality of support braces 8 extending upwardly from an upper convex plate 10. A lower convex plate 12 forms part of the clothes washer base. A snubber shuttle I4 is sandwiched between the upper convex plate 10 and the lower convex plate 12. The snubber shuttle 14 is free to move according to the forces applied by the upper and lower convex plates. The upper convex plate 10, and, therefore, the support braces 8, support plate 6, and outer tub 4 are centrally located with respect to the washing machine casing by a plurality of suspension springs 15. Frictional forces between the plates 10 and I2 and the snubber shuttle 14 provide the dampening forces for the suspension system. The springs 15 not only provide a centering bias for the suspension system, but also provide a downward force which, along with the weight of the washing machine components and clothes load, help increase the dampening characteristics by increasing the frictional forces between the snubber shuttle l4 and the plates 10 and 12. My copending application Ser. No. 766,198, now US. Pat. No. 3,493,] 18, granted Feb. 3, 1970, describes a suspension system of this type in detail.

Mounted within the outer tub 4 is an inner tub or spin tub 16. In the preferred form of this invention, an agitator 18 is integrally molded with, and centrally located within, the spin tub 16. It is also within the purview of this invention to attach an independent agitator to the spin tub 16 to form a unitary structure. Either way, and considering using a plastic such as polypropylene as the material for molding, a weight savings is obtained.

Supported beneath the support plate is the oscillating and spinning drive mechanism 20 of the clothes washer which is the subject of this invention. Extending upwardly from the oscillating and spinning drive mechanism 20 is the tub drive shaft 22. The tub drive shaft 22 extends through the support plate 6 and the outer tub 4. The tub drive shaft 22 is rotatably mounted with respect to the support plate 6 by a sleeve bearing 23. Located on the upper end of the tub drive shaft 22 is a spin tub support 24. As in the preferred form of this invention, the agitator 18 is integrally molded with, and centrally located with respect to, the spin tub 16. The agitator portion i8 is slipped over the spin tub support 24 so as to provide a driving connection between the tub drive shaft 22 and the integral spin tub and agitator l6 and 18. This driving connection may thus be maintained by the weight of the spin tub l6 and the weight of the load located therein.

DRIVE MECHANISM For a general understanding of my improved mechanism refer now to FIGS. 1 and 2. The oscillating and spinning drive mechanism 20 is driven by a reversible prime mover which, in the preferred form, is a reversible electric motor 28 which also drives a pump 26 (FIG. 2) in the water circulation system of the washing machine. The oscillating and spinning drive mechanism 20 can be analyzed as having rotating drive train 30 and an oscillating or agitate drive means 80.

SPIN DRIVE The rotating drive train 30, as shown in FIGS. 2, 3 and 4, includes a spin drive roller 32 which is made of a polyurethane sleeve surrounding and frictionally engaging a spindle 33 extending from the reversible motor 28. The spin drive roller 32 frictionally drives a spin idler roller 34 which frictionally drives a driven spin roller 36 which is relatively rotatably mounted about the tub drive shaft 22.

The spin idler roller 34 is maintained in position by an idler roller retraction device 40 best shown in FIGS. 4 and 9. The idler roller retraction device 40 is similar to the roller retraction assembly described in detail in the US. Pat. No. 3,287,942, issued to Brackman et al. on Nov. 29, I966. The idler roller retraction device 40 has a U-shaped bracket 42 having arms 44 and 46 held apart by a spacer sleeve 48. Located between the arms 44 and 46 are a pair of

pivot links

50 and 52. A bushing 54 is located between and rotatably mounted by the pivot links 50 and 52. The bushing 54 is located concentrically with respect to the spacer sleeve 48 and has an internal diameter larger than the external diameter of the spacer sleeve so that the bushing 54 may move radially with respect to the spacer 48. An aluminum cast die insert 56 is press fit on the bushing 54. A polyurethane tire 58 is molded on the aluminum insert 56 so that the bushing 54, the insert 56, and the tire 58 form as a unit the spin idler roller 34.

An improved biasing arrangement comprises a part of my roller retraction device.

Tabs

60 and 62 are formed in the U- shaped bracket support arms 44 and 46, respectively. Mounted on the

tabs

60 and 62 are two small coil springs 64 and 66. The springs 64 and 66 also seat respectively in holes 68 and 70 formed in the pivot links 50 and 52, respectively. The two small coil springs bias the pivot links and bushing 54 away from the base of the U-shaped bracket 42. The idler roller retraction device is mounted on the washing machine support plate 6 by a bolt 72 extending through the spacer 48. A tab 74 extends outwardly from the bracket support arm 44 and is inserted in a hole located in the support plate 6 to limit the pivoting of the U-shaped bracket 42 around the bolt 72.

The idler roller retraction device 40 with the spin idler roller 34 is mounted so as to locate the spin idler roller 34 between the spin drive roller 32 and the driven spin roller 36 in a self-energizing manner as shown in FIG. 3 and earlier taught in my US. Pat. No. 3,087,321. The springs 64 and 66 bias the spin idler roller 34 into engagement with the

rollers

32 and 36.

When the spin drive roller 32 is driven counterclockwise (FIG. 3) the spin idler roller 34 will be driven clockwise. The frictional forces between the

roller

32 and 34 along with the biasing forces of the springs 64 and 66 will help draw the spin idler roller 34 into engagement with the spin drive roller 32 and the driven spin roller 36. The driven spin roller 36, now being driven in a counterclockwise direction, will impart this motion to the spin tub 16 through the tub drive shaft 22 and a clutch 136 to be described hereinafter.

However, when the direction of rotation of the spin drive roller 32 is reversed, the frictional forces between the roller 32 and the spin idler roller 34 will work against the springs 64 and 66 so as to push the idler spin roller 34 toward the base of the U-shaped bracket 42, and thus reduce the frictional forces between

rollers

34 and 36 in the rotating drive train 30. Thus, the idler roller retraction device 40 accomplishes its purpose of increasing the frictional driving forces of the rotating drive means 30 during the spin operation of the washing machine, and to reduce a rubbing or scuffing action between the spin rollers during an oscillating or washing action of the washing machine which is described in detail below.

AGITATE DRIVE The oscillating drive train 80 is best shown in FIGS. 2, 3, 4 and 7. The reversible motor 28 directly drives an oscillator drive pulley 82 which is part of spindle 33. The first intermediate pulley 86 is driven by the oscillator drive pulley through a first belt 84. Extending from the first intermediate pulley 86 is a second intermediate pulley 88 which drives another rotating member or driven oscillator pulley 92 by means ofa second belt 90. This pulley drive system provides a speed reduction between the motor and the driven oscillator pulley. Extending downwardly from the driven oscillator pulley is a slider crankpin 94. An elongated member or slider crank arm 96 is rotatably mounted at one end on the slider crankpin 94. A flexible slider crank member or band 98 is connected to the slider crank arm 96 at both ends. The flexible slider crank member 98 forms a continuous bond in that there are no joints throughout its length and it extends or wraps around the outer periphery of a slider crank drum 100 as best shown in FIGS. 3 and 4.

The flexible slider crank member is formed of a material having sufficient flexibility so as to wrap and unwrap repeatedly around the slider crank drum throughout an extended appliance life expectancy of 15 years and having limited stretch characteristics. Several materials have proven satisfactory for the flexible slider crank member, namely, stainless steel in several forms such as bands, or cables in various arrangements. However, in the preferred form, the flexible slider crank member comprises two pairs of continuous

flexible cable members

102 and 104. The cables are of multistranded (19 filament) steel wires twisted together and then covered with a plastic polyamide coating as shown in FIG. 5. The first pair of cables 102 is located slightly above the second pair of cables 104 and is joined to the slider crank arm 96 at an adjustable connection or cable tensioner 106. The first pair of cables 102 partially extends around the slider crank drum 100 and isjoined to the drum 100 by a cable key which fits in a drum indentation 108, (FIG. 8). The lower or second pair of cables 104 is joined to the slider crank arm at the end opposite the adjustable connection 110 and also extends partially around the slider crank drum 64 so as to also be joined to the drum 100 by the cable key 110 at the drum indentation 108.

CABLE TENSIONER The flexible slider crank member is fastened to the slider crank arm 96 by an automatic cable-tensioning device as best shown in FIG. 8. The slider crank arm 96 is rotatably secured to the driven oscillator pulley 92 by the slider crankpin 94. At the end of the slider crank arm 96 furthest from the slider crankpin 94 is a slider crank arm extension 114 having a notch 116. Located toward the slider crankpin end of the slider crank arm 96 is a section extension or projection 118. The extension 118 has a surface 120 which is slanted at a slight angle away from the pin 94. The two pair of

cables

102 and 104 are each embedded at one end thereof in the cable key 110 which in turn fits into the drum indentation 108. The free ends of the second pair of cables 104 are embedded in a cable end piece 121 which in turn is riveted to a flat connector piece 122 having an opening 124. Similarly, the free ends of the first pair of cables 102 are embedded in a cable end piece 125 which in turn is riveted to a connector piece 126 having an opening 128. The second pair of cables 104 is wrapped partially around the drum 100 from the cable key 110 and the connector piece 122 is slid over the end of extension 114 so that the opening 124 may catch in notch 116. The first pair of cables 102 is wrapped from the cable key 1 10 around the slider crank drum 100 in a direction opposite that of the second pair of cables 104. The free end of the first pair of cables 102 having the connector piece 126 is then positioned so that the opening 128 engages the slanted surface 120 of the slider crank arm extension 118. Note from FIG. 8 that as the connector piece 126 is pushed on the sla'nted surface toward the base of the extension 118, greater tension is put on the cables 102, thus tightening the pair of

cables

102 and 104 around the slider crank drum 100. A spring 130 is positioned in a hole 132 of the slider crank arm 96. The free end of spring 130 is pulled upwardly against a spring pin 134 extending through the slider crank arm 96 so that the free end of the spring 130 engages the connector piece 126 of the first pair of cables 102 so as to bias the connector 126 in a cable-tensioning direction on the slanted surface 120. This adjustable connection provides an automatic tensioning on the cables and at the same time provides an automatic adjustment for any wear occurring in the slider crank mechanism. Furthermore, this tension, along with the wrapping of the cables around the slider crank drum, holds the cable key 110 in the drum indentation 108. When it is desired to remove the cables, the connector piece 126 is released from spring 130 and the cable key 110 drops out of the drum indentation 108 so that the whole cable assembly can be removed from the drum and slider crank arm.

AGITATE DRIVE OPERATION As the driven oscillator pulley 92 rotates, the slider crank arm 96 will move through a series of

phantom positions

96, 96', 96 and 96" as shown in FIG. 3 due to the pivotal connection with slider crankpin 94 and the engagement of the flexible slider crank member 98 with the slider crank drum 100. It is readily seen that, as the slider crank arm 96 is moved, the flexible slider crank member 98 will reciprocate tangentially with respect to the slider crank drum 100. Since the flexible slider crank member 98 wraps around slider crank drum 100 and since the flexible slider crank member both fixedly and frictionally engages the slider crank drum 100, the reciprocating tangential motion of the flexible slider crank member 98 will impart an oscillatory motion to the slider crank drum 100. Regardless of the direction of rotation of the driven oscillator pulley 92, the slider crank arm 96 and flexible slider crank member 98 will reciprocate tangentially with respect to the slider crank drum 100 and thus create the oscillatory motion.

As shown in FIGS. 5 and 8, the slider crank drum 100 is positioned so as to oscillate around the tub drive shaft 22. In the preferred form, while the slider crank drum 100 is cylindrical in form, it is mounted slightly offset from the center of the tub drive shaft 22, thus giving an eccentric mounting for the slider crank drum 100 with respect to the tub drive shaft 22. There is a slightly longer moment arm between the slider crank arm and the tub drive shaft 22 when the slider crank arm 96 is at the beginning and end of each stroke, which is when acceleration is highest. Thus, when the slider crank arm is in

positions

96 and 96", as shown in FIG. 3, the slider crank drum will be at a higher eccentricity and thus the speed of changing direction in the oscillation of the slider crank drum 100 is reduced. When the slider crank arm is in midstroke, such as that shown in

positions

96, and 96" in FIG. 3, which is where acceleration is lowest and velocity is highest, the point of tangency of the flexible member 98 with the slider crank drum 100 is of lowest eccentricity with respect to the tub drive shaft 22-a point diametrically opposite the drum indentation 108. While the slider crank drum need not be mounted offcenter with respect to the shaft 22, such a mounting will provide reduced acceleration rates of the slider crank drum when the slider crank drum is changing direction of oscillation.

In the preferred practice of this invention, there will be a speed reduction of approximately 25 to 1 between the oscillator drive pulley 82 and driven oscillator pulley 92. Thus, a motor speed of 1,750 r.p.m. will give a driven oscillator pulley rotation of 70 r.p.m. The radial distance between the center of the driven oscillator pulley 92 and the center of the slider crankpin 94 is approximately 3.14 inches, thus giving a slider crank arm movement of 70 strokes a minute at approximately 6.28 inches per stroke. With the slider crank drum 100 having a radius of 1.466 inches offset approximately 0.20 inches from the center of the tub drive shaft, there will be an oscillation of approximately a 246 per stroke at 70 strokes a minute.

DRIVE CLUTCH AND OPERATION FIGS. 5 and 6 show a simplified clutch member which is utilized in the preferred form of this invention. A drive clutch member or first portion of the clutch 136 is press fit on the lower portion of the tub drive shaft 22 and is further fastened to the shaft 22 by a bolt 138 so that any motion imparted to the clutch 136 is imparted to the tub drive shaft 22. The driven spin roller 36 includes a roller inner sleeve 156 which forms the second portion of the clutch. The inner sleeve 156 is located above the first portion 136 of the clutch and is biased downwardly by a coil spring 150 which seats against a bearing 152. The driven spin roller 36 with the inner sleeve 156 can move axially and rotate with respect to the shaft 22 to condition the first portion 136 of the clutch for either oscillation or rotation. Upward motion of the bearing 152 is prevented by a tub drive shaft pin 154 and the bearing 152 through the spring 150 limits upward axial motion of the driven spin roller 36. The clutch first portion 136 has a tapered outer periphery 140. A sleeve bearing 142 is positioned around the inner stem 1% of the clutch member 136. The slider crank drum which is also the third portion of the clutch, rides on the bearing 142 and has a tapered inner periphery 146. The sleeve bearing 142 has an outwardly extending bearing flange 148 which provides a bearing surface between the slider crank drum 100 and the driven spin roller 36.

The bottom surface of the inner sleeve 156 of the driven spin roller 36 is provided with a cam surface having two vertical portions 160 and two helical portions 162 as shown in FIG. 6. The inner upper surface of the clutch inner stern 144 is also provided with a clutch cam surface having complementary vertical portions 164 and helical portions 166. When the driven spin roller 36 is rotated in a clockwise direction, the cam

vertical portions

160 and 164 abut and the driven spin roller 36 with inner sleeve 156 may move axially with respect to the clutch member 136. The coil spring 150 can now bias the inner sleeve 156 of the driven spin roller 36 downwardly against the bearing flange 148 which, in turn, forces downwardly against the slider crank drum 100. When the slider crank drum 100 is thus biased downwardly, the drum tapered inner periphery 146 engages the clutch tapered outer periphery 140. The two tapered peripheries form a frustoconical friction clutch interface, and, thus, the oscillation motion of the slider crank drum 100 is imparted to the clutch member 136. Since the clutch member 136 is press fit to the tub drive shaft 22, this oscillatory motion will be imparted to the spin tub 16 and agitator 18 to provide an oscillatory agitating or washing motion during the wash cycle of the washing machine. The bolt 138 is utilized to prevent any downward motion of the clutch member 136 and to help secure the press fit of the clutch member 136 to tub drive shaft 22. The driven spin roller 36 oscillates with the clutch 136 and overrides the lightly touching engagement of idler roller 34 in order to effect a nondriving engagement.

When the reversible motor 28 is reversed for a spin operation, and thus, the driven spin roller 36 is rotated in a counterclockwise direction, the cam

helical portions

162 and 166 will engage and thus bias the inner sleeve 156 of the driven spin roller 36 upwardly against the coil spring 150 since the clutch member 136 is fixed relative to the tub drive shaft 22 and cannot move downwardly. As the coil spring 150 is compressed the downward spring biasing force on the slider crank drum 100, through the sleeve bearing flange 148, is relieved and the normal force between the tapered peripheries and 146 is reduced to a point such that the oscillating slider crank drum 100 will slip relative to the clutch 1.36 in order to effect a nondriving engagement. Thus, the oscillatory motion of the slider crank drum 100, which continues throughout the spin, will cease to be imparted to the clutch member 136 and the tub drive shaft 22.

During this counterclockwise rotation of both the reversible motor 28 and the driven spin roller 36, the spin idler roller 34 will be self-energized into a wedging or power transmitting engagement with the driven spin roller 36 by the roller retraction device 40, as explained above. The upward motion of the driven spin roller 36 is limited by the bearing 152 and the tub drive shaft roll pin 154, shown in FIG. 5. This limiting of the upward motion of the driven spin roller 36 insures a continuous engagement of the

helical cam portions

162 and 166 when the driven spin roller 36 is rotated in the counterclockwise direction as viewed in FIGS. 3 and 6. Therefore, the counterclockwise rotary motion of the driven spin roller 36 is imparted to the clutch member 136 through the inner sleeve 156 and the

helical cam portions

162 and 166. Since the spin idler roller 34 is in a-wedging or power-transmitting engagement with the driven spin roller 36 and since the slider crank drum 100 may now slip with respect to the clutch member 136, the counterclockwise rotary motion of the driven spin member 36 overrides any oscillatory motion of the slider crank drum 100 and thus a rotary motion is imparted to the clutch member 136 and tub drive shaft 22. This provides a rotary or spin motion for the spin tub and agitator l6.

DRIVEN SPIN ROLLER CLUTCH A secondary clutch 200 may be provided within the driven spin roller 36. The main purpose of this secondary clutch 200 is to increase the life of the mechanism by providing another surface where slippage can occur during the peak moments of acceleration and deceleration or change of direction of drive of the agitate and spin drive mechanism 20. The secondary clutch includes a clutch plate 202 extending radially from the spin roller inner stem 156 so that motion imparted to the clutch plate 202 is imparted to the inner stem and vice versa. A top clutch lining 21M and a bottom clutch lining 206 are positioned parallel and adjacent the clutch plate 202. Each clutch lining 204 and 206 has an undulating peripheral edge which extends into the complementarily undulating inner surface of the driven spin roller 36 to form a rather splinelike connection therewith so that motion of the driven spin roller is imparted to the clutch linings and vice versa. The bottom clutch lining 206 rides on washer 208 which in turn rides against the bottom cover 210 of the driven spin roller 36. Located directly above the top clutch lining 204 is a clutch spring guide 212. A clutch spring retainer 214 is located near the top of the inside of the driven spin roller 36 and is positioned in one of a plurality of internal grooves 216. A clutch spring 218 is positioned between the clutch spring retainer 214 and the clutch spring guide 212 so as to bias the clutch linings 204 and 206 into a tight sandwich against the clutch brake 202. The plurality of internal grooves are provided so that the clutch spring retainer 214 may be adjusted vertically so as to vary the biasing force of the clutch spring 218 and thus provide a method to adjust the point of slippage of the clutch inner spaces between the clutch linings 204 and 206 with the clutch plate 202.

Rotary motion of the driven spin roller 36 is imparted to the inner sleeve 156 through the clutch linings 204 and 206 and the clutch plate 202. Thus, a clockwise rotation of the driven spin roller 36 as shown in FIG. 6 will impart a clockwise rotation of the inner sleeve 156 so that the vertical cam portion 160 of the inner sleeve 156 can engage the vertical cam portion 166 of the clutch inner stem 144. At this time the spring 150 causes a downward motion of the inner sleeve 156 so as to force the engagement of the slider crank drum 100 with the clutch 136 as described above. When the driven spin roller 36 is rotated in a counterclockwise direction, this counterclockwise rotation will be imparted to the inner sleeve 156 again through the clutch linings 204 and 206 and clutch plate 202. This causes the

helical cam portions

162 and 166 to engage so as to force the inner sleeve 156 upwardly against spring 150 as described above. The compression of the spring 218 is sufficient to eliminate slippage between the clutch linings and the clutch plate 202 during normal mode of operation of the drive mechanism. However, limited slippage may occur at the point when the mode of operation of the drive mechanism is changed if excessive torque might be applied such as during a change from oscillation to spinning or vice versa or during braking. This reduces wear and tear on the mechanism and thus increases the life. it is thus seen that, except when excess torque might be applied, the driven spin roller 36, the clutch 200 and the inner sleeve 1S6 act as a single unit and thus rotate together.

BRAKING The clutch 136 and slider crank drum 100 of this arrangement also provide a unique braking system for the spin tub 16 (HO. 2). At the end of the spin cycle, the power to the reversible motor 28 is shut off causing the motor to stop. The friction between the elements of the rotating drive means 30 resists the rotation of the driven spin roller 36. Similarly, the friction in the oscillating drive means resists the oscillation of the slider crank drum 100. However, even after the motor 28 is shut off, the spin tub 16 continues to rotate due to the inertia of the combined mass of the spin tub 16 and the clothes load located therein. It is desirable to stop the rotation of the spin tub 16 as quickly as possible after the end of the spin cycle. Since the clutch member 136 is joined to the single spin tub shaft 22, the clutch member 136 also continues to rotate in a counterclockwise direction, as shown in FIG. 3. Since the clutch member 136 continues to rotate and the driven spin roller 36 has stopped rotating, there is a relative rotation between the helical cam portion 162 of the driven spin roller and the helical cam portion 166 of the clutch member (FlG. 6). This relative rotation causes the vertical cam surfaces 160 and 164 to again abut, again making possible axial movement of the driven spin roller 36 with respect to the shaft 22. Since axial movement is possible, the coil spring 150 again biases the inner sleeve 156 and thus the driven spin roller 36 downwardly against the bearing flange 148. This downwardly biasing force is then transmitted to the slider crank drum causing the drum inner periphery 146 of the slider crank drum 100 to come into contact with the outer tapered periphery of the clutch 136. The slider crank drum 100 and the clutch 136 are now in the same relative position as occurs during the oscillation drive except that now the slider crank drum 100 is stationary and the clutch 136 is rotating. The rotary motion of the clutch 136 is now imparted to the stationary crank drum 100. As the slider crank drum 100 is rotated, a tangential linear motion is imparted to the slider crank arm 96 through the flexible slider crank member 98. The motion of the slider crank arm 96 is imparted to the driven oscillator pulley 92 against the friction of the oscillating drive means 80. Since the motion imparted to the slider crank drum 100 by the clutch 136 is rotary and not oscillatory, the motion imparted to the slider crank arm 96 is limited by the amount of rotation possible of the driven oscillator pulley 92.

Returning to FIG. 3, it is seen that as the spin tub overruns the rotation imparted to the slider crank drum 100 is in a counterclockwise direction of rotation. If the slider crank 96 is in the position 96', there is a rotary motion imparted to the driven oscillator pulley 92 that will be in a counterclockwise direction. Similarly, if the slider crank arm 96 is in the 96" position, the motion imparted to the driven oscillator pulley 92 will be in the clockwise direction. However, once the slider crank arm 96 has reached the position 96", the forced rotation of the driven oscillator pulley 92 will cause the slider crank arm 96 to move in a direction opposite the tangential linear force being applied by the counterclockwise rotation of the slider crank drum 100. Since the rotation of the slider crank drum 100 prevents the kickback motion of the slider crank arm 96, the slider crank arm 96 will stop in the 96" position. This prevents the slider crank drum 100 from further rotation. Since the slider crank drum 100 is now again stationary, there is relative slippage between the clutch 136 and the slider crank drum 100 (FIG. 5). This slippage creates a frictional braking force on this clutch 136 and thus a braking force on the shaft 22 and the spin tub 16. Due to the use of the slider crank drum 100 as a brake for the drive clutch 136, in the preferred form of this invention, the slider crank drum 100 is made of a friction brake material. During the initial braking action, part of the initial shock of the braking forces is absorbed by the friction of the oscillating drive means 80 by way of the reaction imparted to the slider crank 96. The remainder of the braking reaction force not absorbed, causes a rotation of the total suspended mass in a counterclockwise direction as viewed in FIG. 3. This counterclockwise direction rotation of the suspended mass is then absorbed by the springs of the suspension system (FIG. 1) so that the total shock or jerk of the braking reaction is not absorbed by the flexible slider crank member 98 in the preferred form of this invention.

BELT TENSIONER A belt tensioner assembly 170 (FIG. 7) is used in the preferred form of this invention to provide the proper tension for the belts utilized in the pulley driven system of the oscillating drive means 80. The driven oscillator pulley 92 is rotatably mounted on the support plate 6 by means of a bolt 172 and sleeve bearing 174. Thesupport plate 6 is also provided with an enlarged opening 176. The belt tensioner assembly 170 is provided with an angle bracket 178 mounted below the enlarged opening 176. Located above the opening 176 is a washer 180 having a diameter larger than the internal diameter of the opening. A spacer washer 182 having a thickness slightly larger than the thickness of the support plate 6 is located between the angle bracket 178 and the washer 180. The spacer washer 182 has an OD. smaller than the ID. of the enlarged opening 176. Positioned below the angle bracket is the combination first intermediate pulley 86 and second intermediate pulley 88 on the sleeve bearing 174. The bolt 172 is utilized to hold the belt tensioner assembly 170 together and also mount the assembly on the support plate 6. Since the spacer washer 182 is slightly thicker than the support plate 6, and since the outer diameter of the spacer washer 182 is smaller than the internal diameter of the opening 176, the belt tensioner assembly 170 is relatively free to move radially with respect to the center of the opening 176. The lower end of the angle bracket 178 has an opening 188. One hooked end of a coil spring 190 is inserted through the opening 188 while the other hooked end at the other end of the spring is secured to a bracket 192. The coil spring 190 biases the belt tensioner assembly 170 so as to provide a tension for both the first belt 84 in the first intermediate pulley 86 and the second belt 90 in the second intermediate pulley 88. As noted before, the second belt 90 drives the driven oscillating pulley 92 while the first belt 84 is driven by the oscillator drive pulley 82. The coil spring 190 and thus the bracket 192 are located at an angle so as to provide a tension of approximately pounds on the

first belt

84 and 60 pounds on the second belt 90 through the belt tensioner assembly 170. The assembly 170 is shown in FIG. 3 at a position which will give approximately the proper tensioning for the pulley system in the oscillator drive means 80.

It should, therefore, be seen that an improved oscillating and spinning mechanism has been devised including a single shaft drive system for a lightweight combination spin tub and agitator. This simplified drive system eliminates the need for an oil bath lubrication system and is provided with tensioning systems so as to keep the drive mechanism in proper adjustment. The drive mechanism also utilizes a simplified clutch mechanism which imparts either an oscillatory washing motion or a rotary spin motion dependent upon the direction of rotation of a drive motor. The present invention provides a simplified drive mechanism for a washer which is easily manufactured, relatively inexpensive, light in weight, and having good life characteristics due to a combination of self-adjustment features utilizing less critical manufacturing tolerances than those found in other washing machine drive mechanisms.

While the embodiments of the present invention as herein disclosed constitute the preferred forms, it is to be understood that other forms might be adopted.

lclaim:

1. In combination, a washing machine having a lightweight unitary spin tub and agitator, and a drive mechanism to selectively oscillate and rotate said spin tub and agitator, said drive mechanism comprising; a single shaft: means, a tub support located at one end of said single shaft means, said tub support extending into and covered by the agitator portion of said spin tub and agitator, a reversible motor rotatable for driving said shaft means, support means for said motor and said shaft means, clutch means at the other end of said shaft means for selectively oscillating and rotating said shaft means, rotatable means driven by said reversible motor and rotatably mounted with respect to said shaft means, said rotatable means axially movable with respect to said shaft means to selectively condition said clutch means for oscillation or rotation, a slider crank mechanism driven by said reversible motor, oscillatable means oscillated by said slider crank mechanism upon rotation of said motor in either direction, said oscillatable means being located with respect to said clutch means so as to engage said clutch means when said rotatable means conditions said clutch means for oscillation by rotation of said motor in a first direction, and said clutch means upon rotation of said motor in an opposite direction being condition for rotation by axial movement of said rotatable means and being clrivingly rotated by said rotatable means, whereby the motion of said clutch means is imparted to said unitary spin tub and agitator through said single shaft means.

Claims

1. In combination, a washing machine having a lightweight unitary spin tub and agitator, and a drive mechanism to selectively oscillate and rotate said spin tub and agitator, said drive mechanism comprising; a single shaft means, a tub support located at one end of said single shaft means, said tub support extending into and covered by the agitator portion of said spin tub and agitator, a reversible motor rotatable for driving said shaft means, support means for said motor and said shaft means, clutch means at the other end of said shaft means for selectively oscillating and rotating said shaft means, rotatable means driven by said reversible motor and rotatably mounted with respect to said shaft means, said rotatable means axially movable with respect to said shaft means to selectively condition said clutch means for oscillation or rotation, a slider crank mechanism driven by said reversible motor, oscillatable means oscillated by said slider crank mechanism upon rotation of said motor in either direction, said oscillatable means being located with respect to said clutch means so as to engage said clutch means when said rotatable means conditions said clutch means for oscillation by rotation of said motor in a first direction, and said clutch means upon rotation of said motor in an opposite direction being condition for rotation by axial movement of said rotatable means and being drivingly rotated by said rotatable means, whereby the motion of said clutch means is imparted to said unitary spin tub and agitator through said single shaft means.