US 2078139 A
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2 Sheets-Sheet 1 25'. 3 #42141 4 Hts Attorney.
Irfiv ent or Osmund Ho1m-HanSen,
April 20, 1937. o; H'OLM-HANSEN WASHING MACHINE Filed March 28, 1936 April 20, 1937. o. HOLM-HANSEN WASHING MACHINE Filed March 28, 1936 2 Sheets-Sheet 2 Inventor": Osmuncl Holm-Hansen,
Patented Apr. 20, 1937 UNITED STATES acts-ass wssnme moms Osmiind Helm-Hansen, Stratford, m, alsignor to Generaljileciric company a corporation of New York Application March 28, 1938, Serial No. 71,422
Claims. (01. 259-101) The present invention relates to domestic washing machines of the type in which washing is eflectedby the oscillatory movement of an agitator mountedwithin the tub.
5 In machines of this type a considerable amount of noise has been produced by the mechanism for producing the oscillating movement of the ltitator.
The object of my invention is to provide an improved construction and arrangement in washing machines of this type which will resultin quieter operation, and for a consideration of what I believe to be novel and my invention attention is directed to the following description and the claims appended thereto.
In the accompanying drawings, Fig. 1 is a sectional elevation of a washing machine embodying my invention; Fig. 2 is a fragmentary elevation in section along the lines I-2 of Fig.
3; Fig. 3 is a top plan view in section along lines 3-4 of Fig. 2; Fig. 4 is a perspective view of the guide for guiding the reciprocating movement of the rack: and Figs. 5 and 6 are sectional views of a modification of the sealing means between the bottom of the tub and the post through which the shaft for driving the agitator extends.
Referring to the drawings, the tub l'is provided with a bead I which rests on the upper edge of a cylindrical skirt 3 which serves as a sosupport for the tub. The arrangement for secur ng the tub to the skirt comprises a clamping band 5 which engages the bead ten the tub and a bead 4 on the skirt and thereby wedges the tub tightly against the upper edge of the 35 skirt. The upper edge of the skirt may have a plurality of spaced slots so that the clamping band will clamp the skirt tightly against the tub. The lower end of the skirt is provided with suitable supporting casters 6. A tubular post I 49 extends through a central opening in the bottom of the tub upwardly to a point above the normal water level at the top. A vertical shaft I for driving and an agitator .9 is iournalled at the upper end of the post in a bearing ll. 45 The coupling between the shaft and the agitator comprises a splined nut ll fixed to the upper end of the shaft; which fits into a complementary opening in a bushing i2 moulded in a rubber hub II. The lower end of the huh I! is secured 50 to a flanged sleeve i4 threaded into the upper end of the agitator. The hub it provides a resilient support for the agitator and also provides a torsionally resilient driving connection between the oscillatory shaft I and the agitator. This driving connection decreases the shock resulting from the sudden reversal of the agitator, and also causes the reversal of the agitator to occur after the reversal of the shaft I. The hub II also prevents leakage around the shaft 8 of water which is splashed over the upper 5 end of the hub. At the lower end of the agltator is an annulus ii of rubber bonded to a metal ring Ilb which is secured to the agitator. The annulus It bears on the outside of the post I and provides a resilient bearing for guiding 10 the agitator. This bearingprevents noise due to the wobbling of the agitator with respect to the post 1. The rubber bearing I! has very low friction with water lubrication and has the further advantage that it is not harmed by par- 15 ticles of grit in the washing solution.
Thelower end of the post 1 is bolted to the upper side of a gear casing I is containing the driving mechanism for oscillating the agitator shaft I. The agitator shaft 8 extends within 20 the gear casing lid and has a pinion it keyed to its lower end which is adapted to mesh with.
a reciprocating rack ll to cause oscillation oi? the agitator. The left end of the rack is provided with a crank pin I! which is rotatable 25 in a bearing eccentrically located in a worm wheel it. The worm wheel is fixed to the lower end of a vertical shaft which is journalled in a bearing 2| in a tubular wringer post 22. The wringer post is clamped to the upper side of the gear casing by a split clamp 23 integral with the upper wall of the gear casing. The worm wheel I! is rotated by a worm 24 which is driven by an electric motor 25 carried on the gear casing by rubber rings 26 clamped to supports ll. An intermediate shaft 28 is connected between the motor shaft 29 and the worm shaft 3|! by flexible couplings II. A thrust ball 32 is provided at the left end of the worm shaft 30. The thrust ball is adjusted by a plug 33. With this arrangement the worm wheel I! is continuously rotatedin one direction by the motor and the crank pin it bearing in the worm wheel causes the rack I! to be reciprocated. Thebody 0f the rack is oil-set and rigid sothat although the end of the rack carrying the crank pin II is below the teeth of the worm wheel N, the teeth of the rack and the bearing of the crank pin are in line with the teeth of the worm wheel.
This reduces the. load on the bearings of the shaft 20 and eliminates verticalforces in the rack thrust which would have a tendency to cause slaps, resulting in objectionable noises. The reciprocating movement of the rack is guided by a guide "a shown lung. 4. The guide has each end of the gear casing.
flanges 34 which extend over the upper and lower sides of the rack. Secured to the lower flanges is a tongue 35 which slides in a groove on the underside of the rack and holds the rack in the guide. From the rear edge of the guide extend ears 36 which are pivoted on the inner end of a plunger 31 slidable in the walls of the gear casing lid. The ears 35 support the rack on the plunger and the pivotal connection between the ears 35 and the plunger permit pivotable movement of the guide during the reciprocating movement of the rack. Between the outside of the gear casing and the plunger 31 is arranged a coil spring 38 which biases the plunger outwardly and thereby tends to move the plunger to a position in which the rack is out of engagement with the pinion. The plunger is moved inwardly by a control lever 33 pivoted on a bracket 40 secured to the outside of the gear casing. The inner end of the control lever is provided with a cam surface 4| which engages a set screw 42 threaded into the plunger. 'When the control lever is in the position shown in full lines in Fig. 3, the plunger is pushed inwardly, thereby moving the rack into'mesh with the pinion. When the control lever is in the position shown in dotted lines in Fig.3, thespring 38 moves the plunger outwardly, thereby moving the rack out of engagement with thepinion.
On the underside of'the crank pin 18 is a pin 42a which is pressed by a coil spring 43 against the gear casing cover 44. The friction between the pin 42a and the cover of the gear casing tends to prevent over-travel of the reciprocating rack,"and thereby. reduces back lash between the worm and the worm gear. The friction between the pin 42a and the gear casing cover also tends to retard the rotation of the crank pin l8, and thereby tends to hold the crank pin against its bearing in the worm wheel l9 during all parts of the reciprocating movement of the rack and particularlyduring the reversal of the reciprocating movement of the rack. The frictional force between the crank pin and its bearing is always in the same direction, and causes the rack to be urged outwardly against the back of the guide 34a, thus preventing wobbling of the rack in the guide and eliminating noise from this source. When the rack is being reciprocated, it is continuously held against the back of the guide 34a and the tongue 35 is then merely a means for making sure that the rack is pulled out of mesh with the pinion-in case of binding between some of the parts. The pin 42a prevents the crank pin I8 from falling from its bearing in the worm wheel l9, and also supports the wringer shaft 20. V
In order to prevent transmission of noise originating in the gearing casing to the tub and the skirt 3 which serves as the tub support, I have provided a resilient mounting for the gear casing for preventing metallic contact between the gear casing and any part or the tub or the skirt. Thismounting comprises rings 45 of rubber or other resilient material which arearranged on either side of a flange 45 of a bracket 41secured to the skirt 3. The parts are held in assembled relation by a. bolt 48 extending through the rings 45. A clearance hole 49 in the flange 46 prevents metallic contact between the bolt and the flange. .A resilient support of this construction is provided between the skirt 3 and At the left end of the gear casing, the resilient support is located between the gear casing cover 44 and the skirt. At the right end of the gear casing, the resilient support is located between a bracket 49a and the skirt. In order to prevent transmission of noise from the gear casing through the wringer post 22, I have provided a similar resilient mounting between the tub and a collar 50 which is adapted to support a wringer. This mounting comprises pads 5| of resilient material which are arranged on either side of the tub and which are held in place by screws 52 threaded through clearance holes in the tub into the collar. A resilient mounting is also provided between the post land the bottom of the tub. This mounting comprises rings 53 of resilient material which are arranged on either side of the tub and which are clamped between a flange 54 on the post I and a nut 55 threaded on the post. The rings 53 also serve as a water tight seal.
With this arrangement there is no metal to metal contact between the gear casing and the tub or the skirt 3 and the transmission of noise is prevented by a sound insulating connection ateach point of connection between the gear casing or its connected parts and the tub or the skirt. The transmission of noise originating in the driving mechanism is therefore considerably decreased and quieter operation of the washing machine is obtained.
The resilient support for the driving mechanism for the washing machine has an additional function of preventing noisedue to distortion of the gear casing. 'If the gear casing were rigidly attached to the skirt 3, any unevenness in the floor would cause distortion of the skirt and this distortion would produce a stress tending to bend the walls of the gear casing. The bending oi. the walls of the gear casing would change the mesh of the gears journalled in the casing and would thereby produce an additional source of noise due to interference between the gear teeth. With a resilient mounting for the gear casing, or any equivalent mounting such as a three point suspension of the gear casing, the distortion of the skirt, due to unevenness in the floor, or to rough handling during transit does not stress the gear casing and, therefore, does not change the mesh of the gear teeth. This means that the gear mesh of the gear teeth is independent of inequalities in the floor and that changes in the adjustment of the mesh of the gears are not required. Also, with this construction for supporting the gear casing, the gear casing may be made less rigid.
If the resilient mountings illustrated were replaced by rigid connections, oscillating torque applied to the agitator shaft 8 would be transmitted through the agitator post! and through the wringer post 22 to the tub. Since the tub is made of relatively light metal these forces would cause bending of the tub, and the reaction from the tub to the skirt 3 would tend to distort the walls or the gear casing. This distortion which would be an additional source of gear noise is prevented by the resilient mounting of the gear casing.
Figs. 5 and 6 shows. modification of the resilient connection and seal between the post i and the bottom of the tub. This resilient connection comprises a bushing 56 of rubber having against the edges of the opening in the tub and thereby provides a tight seal between the tub and the bushing. The inherent resilience of the flange 58 also effects a tight seal between the post I andthe bushing.
What I claim as new and desire to secure by Letters Patent of the United States is:
1. In a washing machine, a tub. a shaft extending through the bottom of the tub, means for oscillating the shaft, an annulus of resilient material connected to and depending around said shaft, and an agitator supported from the lower end of said annulus.
2. In a washing machine, a tub having an opening in the bottom thereof, a tubular post projecting through said opening, a shaft extending through the post adapted to operate washing apparatus in the tub, and a seal between the post and the tub comprising a bushingof resilient material having a portion on one side of the tub and having a portion forced against the opposite side of the tub by outward deformation caused by engagement with side of said post.
3. In a washing machine, a tub having an opening in the bottom thereof, a tubular post projecting through said opening, a shaft extending through the post adapted to operate washing apparatus in the tub, and a bushing of resilient material in said opening having a groove into whichthe edges of the tub fit and having an inwardly projecting portion bent outward by engagement with the sides of said post and thereby forming a water-tight seal between the bushing and the tub and post.
4. In a washing machine, a tub having an opening in the bottom thereof, a tubular post projecting through said opening, a shaft extending through the post adapted to operate washing apparatus in the tub, and a resilient seal in the opening between the post and the tub for preventing transmission of vibrations from the post to the tub, said seal comprising a bushing having a groove engaging the edges of said opening and an inwardly extending flange at one side of the bushing pressed outward by engagement with the sides of said post and causing the sides of the groove tightly to engage the tub.
5. In a washing machine, a tub, a shalt extending through the bottom of the tub, means for oscillating the shaft, a hub of resilient material connected to the shaft, said hub enclosing the upper end of the shaft and having an annulus of resilient material depending around the shaft, and an agitator supported from the lower end of said annulus.