US2893251A

US2893251A - Washing machine transmission

Info

Publication number: US2893251A
Application number: US530178A
Authority: US
Inventors: Irvin E Mcwethy
Original assignee: Midwest Manuf Corp
Current assignee: Midwest Manuf Corp
Priority date: 1955-08-23
Filing date: 1955-08-23
Publication date: 1959-07-07
Anticipated expiration: 1976-07-07

Description

/ J y 1959" |.C'E.-M0WETHY 2,893,251

. WASHING MACHINE TRANSMISSION Filed Aug. 23, 1955 3 Sheets-Sheet 1 w 42 INVENTOR- v V; fl'flfild BY i f, 0r 49 271-- ;(4 8 MJATTOMEY July 7, 1959 E. M WETHY 2,893,251

WASHING MACHINE TRANSMISSION Filed Aug. 23, 1955 3 Sheets-Sheet 2 July 7, 1959 E. M WETHY WASHING MACHINE TRANSMISSION 3 Sheets-Sheet 3 Filed Aug. 25, 1955 United States Patent WASHING MACHINE TRANSMISSION Irvin E. McWethy, Cincinnati, Ohio, assignor" to ,lVIidwest Manufacturing Corporation, Galesburg, lll'.

. Application August 23,1955, Serial No. 530,178

v 8 Claims. (chm-42' 1 This invention relates to impr vements in power trans mission: mechanisms for translating rotary move'nie'rit into reclprocatory movement and particularly'toa transmission useful in washing machines or the like Although it is not new to apply motion by an a itator tofsoil ed' clothes in adetergent for cleaning them, the moti'oh imparted to the clothes by washing machine apparatuses of the prior art was ilniform', regardless of the class of fabrics which were being cleaned. This made necessary to provide a degree of movement to the agitator which wouldxresult in sufficient agitation of the greater bull of clothing that is ordinarily composed of relatively strong fabrics. The same amount of agitation when applied to' the more fragile fabrics resulted in injury to such fabrics; x

To' eliminate the foregoing disadvantages; I have dc vised a novel washing machine transmission capable of imparting to a washing machine agitator a plurality of grades of movements, each ofwhich' may be selected for a particular grade of clothes to be washed, the selection Being made by novel control apparatus. Also, additional remote control apparatus isemployed for interrupting the operation of the agitator at any time during washing without changing the setting of the transmission for in!- p'artih'g a selected uniform-motion to the agitator.

The manner of operation and the construction of the apparatus, as weir as certain advantages due to the construction, will become more apparent from the following description of an embodiment thereof, the description being illustrated by the accompanying drawings and form ing' apart of this specification.

the drawings v Fig. I is a diagrammatic view of washing machine appa atus, artly inelevation and artl in perspective, in which the invention is inco porated;

Fig 2 is an exploded view of the apparatus; some of level of the eye of an observer and one inside elevation;

Fig. 3 is a fragmentary perspective view of the movable key and element for operating it;

Fig. 4 is a" fragmentary section taken on line of Fig. 1;

v the elements of which are shown above, some below the Fig. 5 is a fragmentary top plan view or the elements shown Fig. 4, the same being observed while'the cover is removed;

Fig. 6 is a top plan view of the casing in which elements of the transmission are contained;

' Fig. 7 a view corresponding to Fig. 6, a portion of 3 2 ,893,251 Patented July 7, 1959 shown, such as an electric'motor, the constant motion of the shaft being translated into an oscillatory motion of the agitator by a transmission mechanism of a novel nature now to be described. i

To understand the transmission mechanism it is advisable to first consider the housing or frame therefor. It is indicated in its entirety by the reference character 6 (Figs. 2, 6 and 7), and includes upper and

lower sections

7 and 8 formed with ears 9 at their engaging edges whereby the sections may be bolted together to provide a cavity 11 within the casing. Therein, and at one end thereof, a gear 12 (Fig. 1) is rotatably journalled on a stub shaft or pintle 13 fixed in the section 8. The gear 12 meshes with a pinion 14, fixed and driven by the shaft 4 in one direction. The gear 12' serves as one memberof a clutch 15 which drives an annular member 16 through a coupling to be described.

Spaced from the gear 12, in the cavity 11, is a swing'able member 20- pivotallymounted on a post 18, carried on the section 8. It derives motion from the clutch member 1 5 by a pitman 19. For its relationship to adjoining parts, the pitman has, at one end a crank pin or pivot pin 21 (Fig. 2) which is' journalled in a bore or socket 22 in the annular clutch member 16, eccentric to the axis of said member. The remaining end of the pitman also carries a pivot pin 23 which is journalled in a bore 24, of the swingable member 20, at a point spaced from the post 18. Thereforewhen the clutch member 16 is rotated, the member 20" is swung alternately in opposite directions about its pivot" 18'. This provides a source of oscillatory motion for the agitator 3, which is communicated thereto from the member 20 by a shaft 26, to which the agitator is secured, a pinion 31 meshing with an internal gear or rack segment 17, on the member 2 0 and a jaw clutch 28 for intermittent driving connection between the member 20 and shaft 26. In greater detail, the clutch 28 includes a member 27', slidably keyed to the shaft 26, which has lugs 25 engageable in notches 30 of a second clutch or driving member 29' which may be integral with the pinion 31.-

The clutch 28 may be operated from a point remote therefrom by means including a yoke 71 embracing the member 27 and having, on either side thereof, pins 72 extending inwardly of the yoke into an annular groove 73 in the clutch member 27. Atone end thereof, the yoke 71 is formed with an arm 74'which is pivoted at 76 to a stationary part of the washingmachine" frame, not shown, while the remaining end of the yoke 71 has an car 78 pivoted at 79 to a solenoid bracket 81. Current carrying

wires

82, 83, and 84 are arranged to supply current to a solenoid coil 86, cooperatively associated with a solenoid armature 85 carried by the bracket- 81, and-may be energized by current supplied from any con venient source by the Wires when a switch 88 is closed. When the switch 88 is closed, resulting in energization' of the coil 86; the armature 85 is drawn upward and concurrently the clutchjaw 25 is withdrawn from the notch 30' to interrupt driving of the shaft through the clutch 28. Onopening of the switch 88, the solenoid 86 is de-en'e'rgized and as a result gravity restores the driving cooper'a tion between thejaw 25 and notch 30; It will be appreciated that this may be replaced by" a purely mechanical operation of the lever and that other types of clutches may be used at this point without interfering with the operationof the other portion of the invention.

Since different classes of fabrics call for different dc g'rces of agitation for their most 'efiicient cleaning, provision is made for swinging the agitator through a plurality of selectable arcs by varying the movement of the pitman 19. This is carried out as follows: The upper side of'the gear 12 is formed with a circular groove, channelor way 32 therein (Fig. 2') the axis of which iseccentric to the axis of the gear and which includes inner and

outer side walls

33 and 34 between which the second or inner clutch member 16 is received, the walls affording bearing surfaces for said member. The inner wall 33 of the groove therefore defines a hub 35 in the gear 12. The upper end of the hub is also formed with a groove 36, in its periphery (Fig. 8) for the reception of a spring C-Washer 37. The member 16 is counterbored at 38 to accommodate the C-washer 37 when in the groove 36. The Washer 37 thus serves to anchor the member 16 in the groove 32 and on the hub.

Since the way 32 is eccentric to the axis of the gear 12 relative angular displacement between the inner and

outer clutch members

12 and 16 is accompanied by variations in the distance between the axis of the gear and crank pin 21. Advantage is therefore taken of novel interlocking means, later to be described, for releasably securing the member 16 in a selected angular position relative to the gear 12. When unlocked from the member 16, the gear may turn to another selected position relative to the member 16 and may be locked to said member in the new selected position. To accomplish this the member 16 is formed with a plurality of notches or keyways 39 in its periphery. The outer wall 34, of the groove 32, is formed with a slot or keyway 41 extending radially of the groove 32 and in which a preferably rectangular plate, key element or dog 42 is slidably disposed. The dog 42 is movable edgewise between extended and retracted positions during which it is guided by the opposed walls of the keyway 41. In its extended position, the dog 42 is embraced by the walls of one of the keyways 39 to drivingly couple the clutch member 16 to the gear 12. When the dog 42 is retracted whereby it is advanced farther into the keyway 41, it is free from engagement by the member 16 so that the gear 12 may be turned relative to said memher, the load of the agitator and parts linked thereto then being adequate to resist turning of the member 16.

Laterally of and communicating with the keyway 41 is a plunger recess or socket 43 parly defined by opposed guide or side walls 44, between which a follower element 46, of height less than the height of the dog 42 and also formed with opposed sides 47, is confined for vertical movement. Vertical movement of the element 46 is accompanied by horizontal movement of the dog 42. This is due to a cam-and-follower connection between the elements to positively couple them together. Specifically, Fig. 3, one of the sides of the dog 42 is formed with a diagonally extending cam slot 48 in which is received a first follower 49 formed on the edge of the element 46. For the sake of the advantages gained by a large bearing surface in the space available, the follower 49 may appropriately take the form of a rib extending diagonally of the follower element. Both the dog and

follower

42 and 49 are retained against displacement upward and out of the recess in the gear 12 by a plate 51 bolted to said gear in a shallow recess 52. Although the plate 51 is intimately associated with the dog 42, it is normally spaced from the top of the follower element 49. This is due to the biasing effect of a compression spring 53 confined between the corner and the bottom of a bore 54 in the follower element. When the element 49 is in its normal position, the dog 42 is extended to be operatively engaged in one of the keyways 39. When the element 49 is moved upward against the resistance of spring 53, by means later to be described, the dog 42 is retracted from the clutch member 16 so that the gear 12 may turn relative to the clutch member.

For unclutching the

members

12 and 16 from each other, the follower element 49 is formed with a second follower or stud 56 which projects through a bore 57 in the gear 12 at the bottom of the socket 43 to a point below the level of said gear. The stud 56 is therefore carried through a predetermined arc when the

members

12 and 16 are clutch-coupled to each other in the manner aforesaid. Alvertical shaft 58 is journalled in a sleeve or bearing 59 (Fig. 2) extending downward from the upper section 9 and slightly thereabove and spaced from the gear 12. The upper end of the shaft 58 extends above the level of the sleeve above the top of the casing 7 and has a crank arm 61 fixed thereto. The outer end of said arm bears a handle 62 by which the shaft may be turned manually. It will be appreciated that this arm may also be moved mechanically or electrically if desired. Below the level of the gear 12 the shaft 58 supports, in fixed relation thereto, an arm 64, the swingable end of which is formed with a vertically effective cam 66. The arm 64 is normally held in engagement with a stop pin 67, on the lower section 8, by a spring 68 which has one end anchored to the arm and the other to a pin 68'. This normally retains the cam 66 out of the course of the follower 56. When a change in the operation of the agitator is desired, the lever 61 (Fig. 6) is moved to turn the shaft 58 against the resistance of the spring 68 until the cam 66 is in the course of travel of the second follower 56 (Fig. 7) which is moved upward as it passes over said cam. The upward movement of the first follower 49 moves the dog 42 to its retracted position, thereby freeing the gear 12 to turn independently of the annular member 16. The cooperation between the second follower 56 and cam 66 may be made to take place for a small portion of angular displacement of gear 12 relative to the member 16 after which the outer edge of the dog 42 rides on the periphery of the inner clutch member 16 until the dog is in registration with the next keyway 39 into which said dog snaps, due to the force of the spring 53. Driving relationship between the

clutch members

12 and 16 is then restored, at which time the pitman is moved through a stroke differing from the one it last moved in.

Inasmuch as the groove 32 is eccentric to the axis of the gear 12 this results in the movement of the socket 22 about the axis of the inner clutch member resulting in the socket removing closer to or away from the gear axis and hence shortening or lengthening the radius from the socket to the gear axis with a resultant shorter and greater movement of the pitman. The amount of stroke of the pitman determines the degree of arcuate movement of the swingable element 20 and hence the degree of turning of the pinion 31 and the driving member 29. This in turn determines the degree of revolution of the agitator which can be adjusted, depending on the number of keyways 39, to turn any desired portion of revolution. Although four of the keyways are shown it is within the purview of my invention to provide more or less. Four is normally considered sufficient for most purposes.

As has been stated, it is only necessary to operate the lever 64 for a short time to enable the follower 56 to ride upon the cam 66 and disengage the gear from the inner clutch member. Since the gear continues its rotation it immediately passes over the follower leaving the inner clutch member behind and does not pick it up until it engages in the next succeeding keyway. This movement is accompanied by audible clicks as the follower passes over the cam and enables the user to hold the lever for one or more revolutions of the gear after which it may be released to thus quickly adjust the drive for the desired degree of reciprocation.

While I have described my invention in an embodiment thereof, I am aware that numerous and extensive departures may be made therefrom without departing from the spirit or scope of my invention.

I claim:

1. A transmission for converting a rotary motion to a reciprocatory motion including a rotary driven gear and means for driving said gear at a substantially constant speed, a pitman eccentrically connected to and reciprocated by said gear and means driven by said pitman, said connection for the pitman to said gear comprising an annular member rotatably journalled in an eccentric groove in said gear and formed with a socket for receiving a crank pin on the'; pitman; means'for releasably coupling the annular member to thegear, and means to vary the position of the socket relative to the gear axis by interrupting the coupling between the gear and: annula'r' member comprising a follower supported by the gear and controlling the coupling between the gear arid the annular member, andanactuator movable into the path of movement of saidfollower asthe" gear rotates to displace said followerto uncouple the gear from the annular niem ben- I 2. An apparatps of the elass descri-bed including associated driven and drivable clutch members, a pitman pivotd to the" drivable" member at a fixedpoint thereoneccentric to the axis of said drivable member, one of the members being formed with a plurality of keyways on its side adjacent the other member, a movable key supported by said other member and arranged to be extended into one of the keyways to drivingly couple said drivable to said driven member and be retracted from the keyway to permit angular displacement of said driven member relative to said drivable member and for the key to be then extended into a different keyway, a key shifter also sup ported by said other member, and a cam and follower connection between the key and key shifter positively connecting said key and said shifter together whereby said key may be shifted between its extended and retracted positions by movement of the key shifter, the axes of the members being out of coaxial relation to each other for the eccentricity of the pivot point to be varied relative to the axis of the driven member with each change in the keyway engaged by the key and thereby for the stroke of the pitman to be varied.

3. A power transmission mechanism comprising a driven disc formed with spaced inner and outer guide sur faces normal to the plane of the disc to provide an annular track, an annular member in the track, said annular member being formed with a plurality of radially extending keyways at its periphery, a key arranged in confined relation to the disc exteriorly of the track for movement into one of the keyways by being moved to an extended position thereof to drivingly couple the members together and be moved out of the keyway to a retracted position thereof to free the disc for it to turn relative to the annular member thereby for the key to be carried to a different keyway into which said key may be extended, a key shifter by which the key may be shifted between its extended and retracted positions by being positively coupled to said key, and a pitman pivoted to the annular member, said track being eccentric to the axis of the disc for the pivotal axis of the pitman to be varied relative to the axis of the disc with each change in the keyway engaged by the key and the stroke of the pitman thereby varied.

4. An apparatus of the class described including associated driven and drivable clutch members, a pitman pivoted to the drivable member at a fixed point thereon, one of the members being formed with a plurality of keyways on its side adjacent the other member, first and second movable elements carried by one of the members, a cam and follower connection between the elements for communicating motion of either of said elements to the other element, and means engaging one of the elements to bias both of said elements to predetermined positions, the first element being thereby moved into one of the keyways and acting as a key therein to drivingly connect the members together and being removable from said keyway by moving the second element against the force of said means thereby freeing the driven member to turn relative to said drivable member and a different keyway to be engaged by the first element when the second element is released, the axes of the members being spaced from each other for the eccentricity of the pivot point to be varied relative to the axis of the driven member with each change in the keyway engaged by the key and thereby for the stroke of the pitman to be varied.

5. Apower transmission mechanism comprising a driven disc formed with spaced inner and outer guide surfaces normal to the plane of the disc to provide an annular track, an? annular member in the track, said annular member being formed with a plurality of radially extending keyways atitsperiphery, first and second movableelements carried by the disc and arranged in confined relation to said disc exteriorly of the track, a cam and follower connection between the elements for communicating motion of either of the elements to the other element, means engaging one of the elementsgto: bias the first of said elements into one of the keyways therein for said first element to act as a key to drivingly connect the members together and being removable from said keyway to moving the second element against the resistance of said means thereby freeing the disc to turn relative to the member and carry the key into registration with a different keyway and for said key to enter said different keyway when the second element is released, and a pitman pivoted to the annular member, said track being eccentric to the axis of the disc for the pivotal axis of the pitman to be varied relative to the axis of the disc with each change in the keyway engaged by the key and the stroke of the pitman thereby varied.

6. A transmission for converting a rotary motion to a reciprocatory motion including a rotary driven gear and means for driving said gear at a substantially constant speed, a pitman eccentrically connected to and reciprocated by said gear and means driven by said pitman, said connection for the pitman to said gear comprising an annular member rotatably journalled in an eccentric groove in said gear and formed with a socket for receiving a crank pin on the pitman, means for coupling the annular member to the gear comprising a dog supported by the gear and movable inwardly of the gear into recesses formed in the periphery of the annular member, and means to move said dog comprising a cam having an oblique land cooperating with an oblique keyway on the dog, said cam extending beyond the surface of the gear, and a cam lifter disposed adjacent the gear and movable into the path of travel of said cam as the gear rotates for moving the cam and retracting the dog to thereby uncouple the gear from the annular member.

7. A transmission for converting a rotary motion to a reciprocatory motion including a rotary driven gear and means for driving said gear at a substantially constant speed, a pitman eccentrically connected to and reciprocated by said gear and means driven by said pitman, said connection for the pitman to said gear comprising an annular member rotatably journalled in an eccentric groove in said gear and formed with a socket for receving a crank pin on the pitman, means for coupling the annular member to the gear comprising a dog supported by the gear and movable inwardly of the gear into recesses formed in the periphery of the annular member, and means to move said dog comprising cam means in engagement with said dog and extending beyond the surface of said gear and a cam lifter disposed adjacent the gear and movable into the path of travel of said cam as the gear rotates for moving the cam and retracting the dog to thereby uncouple the gear from the annular member.

8. An adjustable stroke transmission comprising a rotary gear mounted for rotation about a predetermined axis, means driving said gear for continuous rotation, a hub connected to said gear to turn therewith, said hub having a circular periphery which extends around said axis eccentric thereto, an annular member extending around the hub, said annular member having a circular inner periphery which is concentric with the circular periphery of the hub and closely receives the latter for relative rotation between the hub and the annular member, means carried by the gear for coupling the gear to the annular member so that the annular member is turned by the gear eccentrically about said predetermined axis as the gear rotates about said axis, a connecting rod connected to said annular member to be reciprocated thereby as the annular member turns eccentrically about said predetermined axis, and means carried by the gear and selectively operable during the latters rotation to 5 actuate said coupling means to uncouple the gear from the annular member so that the hub turns with respect to the annular member and thereby changes the eccen tricity of the annular member with respect to said pre- I References Cited in the file of this patent determined axis to change correspondingly the stroke of 10 2,838,956

said connecting rod.

1 UNITED STATES PATENTS Bowers Aug. 16, 1927 Horton June 21, 1938 Mikulsek Apr. 16, 1940 Michelman Nov. 30, 1948 Baldo Jan. 17, 1950 Maust Nov. 9, 1954 Schneider June 17, 1958 FOREIGN PATENTS France Sept. 7, 1906