US2695104A - Centrifugal extractor balancing means - Google Patents

Description

69591 lili J. G. DE REME CENTRIFUGAL EXTRACTOR BALANCING MEANS nn .m R @n A wm mrv m E V'. um

ATTO/m5@ Wm WW Nov. 23, 1954 Filed Feb. 19, 1949 Nov., 23, 1954 J. G. DE REMER ,9AM

CENTRIFUGAL EXTRACTOR BALANCING MEANS Filed Feb. 19, 1949 zw, X SPIN-DRY 1j:

INVENTOR. JAY GRANT DE KEMER TTONEYS.

Nv. Z3, 1954 v G. DE; REMER CENTRIFUGL EXTRCTOR BALANCING MEANS 6 Sheets-Sheet 5 Filed Feb. 19, 1949 f4 TTONEYS.

Nov. 23, 1954 J. G. DE REMER 2,695,104

CENTRIFUGAL EXTRACTOR BALANCING MEANS Filed Feb. 19, 1949 6 Sheets-Sheet 5 I INVENTOR. JW GRANT DEEE/WER Nov. 23, 1'954 .1. G. DE REMER 2,695,104

CENTRIFUGAL. EXTRACTOR BALANCING MEANS Filed Feb'. 19, 1949 6 sheets-sheet e Pon/Eli' OFF i END of CYCLE JNVENTOR.

JAY 67mm" Dls/PEME@ United States Patent O CENTRIFUGAL EXTRACTOR BALANCING MEANS Jay Grant De Remer, Darien, Conn., assignor to J. G. De Remer Research Corporation, Union City, N. J., a corporation of New Jersey Application February 19, 1949, Serial No. 77,306

1 Claim. (Cl. 210-72) The invention relates to timing devices and, more particularly, to a timing device for controlling the events of a household clothes washing and centrifugal drying machines.

In its preferred form, the invention utilizes a powerdriven, clock-controlled liquid-controlling valve; this fills the machine with wash water, it supplies a flush rinse to the clothes, and it supplies hydraulic pressure to a servomotor for shifting the machine from agitate position to spin position. The machine preferably occupies an agitate position during Washing and ush rinsing. The timer may also control an electric switch which turns off power at the end of the cycle.

In its preferred form, the rotary valve for controlling water supply to the machine, the clockwork, the electric switch and a special booster spring motor may be located on, or grouped around, a single main shaft. A handle may be placed on the shaft to turn the timer to any desired position at will, regardless of clockwork control.

According to the invention, special provision is also made to minimize the friction due to water pressure on the faces of the valve members. In case the timer is used with a machine having water-balancing devices which use water expelled from the clothes, special provision may be made for preventing re-starting the machine without sufficient water for balancing during the spinning operation. This special provision may take the form of a delay action device, making it necessary to pull the handle back to the rinse sector before the timer re-closes the electric switch; or, it may take the form of a special bleeder connection supplying water to the balancing devices whenever hydraulic pressure is used to shift the machine to its spinning position.

The invention also consists in certain new and original features and combinations hereinafter set forth and claimed.

Although the novel features which are believed to be characteristic of this invention will be particularly pointed out in the claim appended hereto, the invention itself, as

to its objects and advantages, and the manner in which it may be carried out, may be better understood by referring to the following description taken in connection with the accompanying drawings forming a part hereof, in which:

Fig. l shows partly diagrammatically the invention as applied to a preferred type of combined and centrifugal drying machine;

Fig. la is a detail plan View illustrating how water is fed to the basket balance rings;

Fig. 2 is a side elevation of the timer;

Fig. 3 is a top plan view of the timer;

Fig. 4 is an end elevation of the timer;

Fig. 5 is a developed View of the timer name plate showing the several stages or operations;

Fig. 6 is a vertical longitudinal section through the timer;

Figs. 7 and 8 are transverse sections taken on the lines 7-7 and 8 8 of Fig. 6 and illustrating the water ports;

Fig. 9 is a section on the line 9--9 of Fig. 6 illustrating the operation of the timer-operated electric switch;

Fig. l0 is a section taken on the line 10--10 of Fig. 6 illustrating the extra power spring;

Fig. 1l is a section on the line 11-11 of Fig. 6 illustrating the drive connection between the clockwork and the power spring;

Figs. 12 to 17 illustrate diagrammatically the position 2,695,104 Patented Nov. 23, 1954 of the timer at the various steps of the washing cycle as indicated;

Fig. 18 is a diagram illustrating the entire automatic cycle; and

Fig. 19 is a detail section of a modified form of valve body and valve plate, using a flow washer on the rinse port.

In the following description and in the claims, various details will be identified by specific names for convenience, but they are intended to be as generic in their application as the art will permit.

Like reference characters denote like parts in the several figures of the drawings.

In the drawings accompanying and forming part of this specification, certain specific disclosure of the invention is made for purposes of explanation, but it will be understood that the details may be modified in various respects without departure from the broad aspect of the invention.

Referring to Figs. 1 and la, the timer will first be described with reference to a preferred type of laundry machine with which the timer may be used. It will be understood that the timer may also be used with other types of washing machine, and particularly those in which the clothes are washed and centrifugally dried in the same basket or container.

The timer, indicated by T, is mounted on the top and to the rear of the washing machine tank 15. It receives Water from a conventional mixing spout 12 receiving water from a hot water faucet 10 and a cold water faucet 11; this type of fixture is commonly used in kitchen sinks. A hose 13 connects mixing spout 12 and the supply nipple 14 of the timer T.

Thegwashing machine is shown somewhat diagrammatically; it comprises an outer tank 15 enclosing a basket 16. The basket is mounted on a suitable pedestal 17 rising from a bottom wall 18 forming the bottom of the tank. Drain 19 connects bottom 18 to sewer for disposal of water. An electric motor 20 drives the machine through a suitable clutch (not shown), operated by a servomotor 21. Servomotor 21 is operated by water pressure, supplied through tubing 22 which leads from the timer T. Electric motor 20 is operated by wires 23 which also lead from timer T. A lead 24 connects timer T with a conventional plug for plugging into a suitable electric outlet to supply electricity to run the machine.

The pedestal 17 contains mechanism for spinning the basket 16 about a vertical axis substantially coincident with the geometrical axis of the basket, for drying. It also contains mechanism for imparting, to the basket during washing, a gyratory motion whereby the geometric axis of the basket partakes of a conical movement about a central point within the pedestal 17. This gyratory movement agitates the clothes. The basket 16 in Fig. l is shown in agitate position.

The basket 16 is of the imperforate type, holding water for washing; it comprises an outer wall 26 and a clothesretaining ring 27 held in position by an annular assembly 28. Assembly 28 contains ducts arranged in such way as to prevent or minimize spillage of water during the gyratory washing action but not to interfere with the discharge of water during centrifugal drying.

To assist in overcoming vibration during drying, the basket is provided with a set of open balance rings 29 and 30 suitably fixed on the basket. These rings are open on the sides facing the basket axis. They `are relatively thin (radially of the basket) and relatively tall (axially of the basket). Within inner ring 29 is a distributing duct 31 also having its inner face open.

During drying, the basket is spun with the geometrical axis of the basket substantially coinciding with vertical. Water centrifugally discharged from the clothes runs up the annular wall 28 through the discharge openings 25 into distributing ring 31 whence it spills over into inner ring 29. When inner ring 29 is filled, water spills over its lower radial wall into outer ring 30. When outer ring 30 is filled, water spills over its lower radial wall into the tank. lt will be understood that, at centrifugal discharge speed, the centrifugal force exerted on the water is many times that of gravity. Therefore, in considering the flow of water, the force of gravity may be ignored. The water distributes itself in the balance rings in such manner as to counterbalance the off-balance spinning mass of basket and clothes.

For a more complete -understanding of the 'structure' of the washing machine, its tank, its basket and balance rings, and operation, reference is rnade lto copending application, Serial No. 12,718, filed March 3, 1948, now Patent No. 2,652,710, granted September 22, 1953.

rThe basket 16 is supplied with water by a suitably supported funnel member 33 adapted to discharge into the open top `of the basket; funnel 33 receives water from supply spout 32 on the timer T. The control tubing 22 has a .bleeder pipe 34 which supplies a second funnel 35, also suitably supported on the tank. The funnel 35 discharges directly into the anti-spill ring 28 to feed the distributing duct 31 and liquid balance rings 29, 30 during spinning of the basket, as described hereinafter. The discharge end of the funnel 35 extends in the direction of spinning movement of the basket 16 (clockwise looking down on the machine as in Fig. 1a) so as to be in proper position when the basket axis is substantiaily vertical during the beginning of the spinning operation.

Referring now more particularly to Figs. 2 to 6, the timer T will now be described. -It consists of a base 5-1 adapted to be secured to the top of the tank; it 4has a re movable cover 52 secured to the base by screws 36. The cover 52 supports a dial plate 53 (see Fig. 5) containing the indicia as shown. The cover 52 has a slot .through which projects the handle ,handle 45 ,has .a removable knob 37. The handle 45 maybe `moved manually up and down, between the positions shown in Fig. 4, to `obtain the various actions indicated on the dial plate 53. The handle is also driven by clockwork.

The handle 45 is secured to the main timer shaft indicated in general -by 44 (Fig. 6). This shaft extends the entire length of the timer and comprises valve shaft 58, tubular shaft 95, and clock shaft 103, all of which rotate as a unit.

Shaft section 58 has fixed thereto .a valve plate 42 for controlling water supply to the washing machine. Shaft section 95 is driven by a special spring motor 43. The rate of powerdriven rotation of shaft section 103 is controlled by clockwork 46 connected through a slip .clutch 47. Shaft section 103 is direct-connected to a switch arm 107 supporting Vroller 48; roller 43 isfengageable with switch lever 49 (Fig. 9) to operate an electric switch 50 to supply electric power to, or disconnect electric power from, the washing machine motor.

-In operation, the handle 45 .may be moved in either direction at .any time by hand. When the hand is re moved, the spring motor 43, under control of clockwork 46, slowly rotates the .main shaft 44 in the direction of the arrow shown in Fig. 4.

Referring to Figs. 6, 7 and 8, the rotary valve will now be described. It comprises a valve head 40 suitably secured to timer base 51. Valve head 40 has a recess 55 in which is located the rotary valve plate 42. Valve head 40 has an annular flange 56 interftting an annular groove in valve body 41; the latter is bolted to the valve head 40 to form a stationary valve casing. Supply conduit 14 (Fig. 8) connects with the interior of head 40 to supply the :recess with water.

Valve head 40 also has a central bore 61 in which is ,fitted bearing member 57 journaling shaft section 58; the latter has secured thereto a balancing piston 59 having .suitable piston rings 60 fitting lbore 61. Drain duct 62 connects bore 61 with discharge spout 32. Helical spring 63 urges valve plate 42 against valve body 41 under .control of certain balancing pressures, described more in detail below.

The valve body 41 has a filling port 66 'in Vcommunication with spout 32; it vhas a rinse port 67 connected to ll port 66 by rinse duct 69. Rinse port 67 has a valve seat controlled by a needle valve 70 (Fig. 6) for adjusting the rate of water ow to rinse duct 69, as lexplained more in detail hereinafter. Adjustable valve 70 is accessible through a plug 71 removable from valve body 41; plug 71 is accessible by removing a cap 72 on the timer cover 52.

The valve body 41 also has a spin port 68 (Figs. 7 and 8) in communication with a coupling 73 connecting with .the control tubing 22 for controlling the servomotor 21. The valve body 41 has raised pads 74 and 75 providing plane faces against which the rotary vvalve plate 42 works to obtain a water-tight seal. 4

'The rotary 'valve plate 42 has a square center hole to accommodate a squared projection 78 on balance .piston 59. Afcotter pin 77 holds the rotary plate 42 against a shoulder on the piston 59. An open space, indicated by 79, is provided to afford free communication from annular recess 55 to balance piston 59. The central space 76dis7a5lso open to annular recess 55 around the pads 74 an Rotary valve plate 42 has ports 80, 81 and 82 (see Fig. k8) adapted to register w-itth the body ports to obtain the various water supplies and connections to control the complete washing cyce, as described more in detail below.

It will be noted that full water pressure is admitted into the annular recess 55 and behind balance piston 59 and into space 76 surrounding square projection 78. The pressure on opposite side of valve plate 42 is balanced except for the areas of the several ports of the valve body 41. This pressure operates to press valve plate 42 to the left in Fig. 6. The area of balance piston 59 is so arranged that the axial pressure on it substantially balances the unbalanced pressure on the rotary valve plate 42. Spring 63 insures a small balance of pressure to hold rotary plate 42 against the pads 74, 75 of stationary valve body 41, to insure ysealing action.

The spring motor 43 will now be described; it comprises a spiral spring connected at its inner end through pin 92 vto tubular shaft 95 forming part of the main shaft 44. The outer end of spring 90 is secured to spring case 87 through .pin 91. Case 87 has a hub 88 journaled on a bearing 96 secured on bracket 89; bracket 89 is secured to timer base 51. Side plates 93 and 94 enclose spring 90.

Spring motor case 87 is mounted in operatively fixed position; the tension of spring 90 may be adjusted by changing the rotative position of case 87. For this purpose, a plurality of adjusting holes 97 is provided in case 87 (see Fig. 1l). A set screw 98 is threaded through a projection on bearing 96 and through ya shoe 99 having a tongue fitting in groove 100 in the case 87. It will be understood that shoe 99 is suitably fixedly secured to bracket 89. To adjust the tension of motor spring 90, it is only necessary to remove set screw 98, turn case 87 and insert the end of set screw 98 in the proper hole 97.

The handle 45 is suitably secured to tubular shaft 95; shaft 95 has a bore receiving valve shaft v58 which is secured thereto bv set screw 86. Handle 45 has a removable -knob 37 to permit assembly and removal of timer cover 52. The ends of the cover slot in kwhich handle 45 moves limits the lower and upper extent of handle movement.

The clockwork 46 will now be described; it is a standard clockwork for running timers. 'It is .preferred to use a two-hour clock; that is to say, a clock whose main shaft takes two hours to run 36() degrees. This means that three degrees of rotation corresponds to one minute of time.

The clock case 101 is secured to bracket 89 by suitable bolts 102. The clockwork shaft 103 is suitably journaled in bearings 104 and 106. Shaft 103 supports switch arm 107 on which is journaled the roller 48 for operating the electric switch.

Iournaled on clock shaft 103 is sleeve shaft 108. A friction washer 47 forming part of a slip clutch is vheld against sleeve shaft 108 lby a clutch plate 109; plate 109 is held in position by a spring 110 operating against a washer set in a groove in shaft 103. Sleeve shaft 108 also bears against a washer 131 set in a groove in shaft 103; these washers take the axial thrust of clutch spring Thus it is possible to move clock shaft 103, .relative to sleeve shaft 108, through slippage of friction clutch 47. Sleeve shaft 108 `may also control the rotation of clock shaft 103 within the limits of torque of slip clutch 47.

Sleeve shaft 108 jhas a series of ratchet teeth 113 engaging pawls 112 on gear wheel 111; wheel 111 is otherwise loose on sleeve shaft 108. Gear wheel 111 is geared tothe usual escapement mechanism (not shown). Clock spring 114 is connected to sleeve shaft 108 by pin 116 and to the clock case 101 by pin 115.

Thus it is possible manually to rotate sleeve shaft 108 (through clutch 47) in such direction as to wind up clock spring 114; the ratchet arrangement 112 and 113 permits such winding up of the clock spring. vThe clock .spring cannot unwind except by driving gear 111 which is under control of the escapement mechanism above referred to.

-T-hecllockwork 46 Aisconnected to the tubular shaft 95 by a universal joint mechanism. This comprises two pins 117 anchored in tube 95 at 180 degrees from each other. It includes a plate 119 having two additional pins 118 disposed 90 degrees from pins 117. Plate 119 has a square opening receiving squared end of clock shaft 103. The oppositely projecting pins 117, 118 work in holes of disc 120. This universal connection allows for any slight misalignment of clock shaft 103 with respect to the motor shaft 95.

Referring now also to Fig. 9, the electric switch 50 is a standard switch such as commonly used for controlling current to electric motors of household washing machines and the like. The electric supply lead 24 and the motor lead 23 are suitably connected to the switch 50, as will be understood by those skilled in the art. Switch 50 is secured to the timer base by a bracket 125.

The switch 50 is controlled by a pushbutton 121 which must be pressed to open the switch; when pressure on the pushbutton is released, the switch closes. The pushbutton 121 is engaged by a leaf spring 122 secured to lever 49; lever 49 is pivoted at 123 to the case of switch 50 and has a stop 124 engaging the case of switch 50 to limit the counter-clockwise movement of lever 49 in Fig. 9. Roller 48 of switch arm 107 engages lever 49 when the clock shaft 105 is rotating in the direction of the arrow in Fig. 9 during normal timing operation of the timer. The engagement of roller 48 with lever 49 moves the lever clockwise in Fig. 9.

The spring 122 is so arranged that the lever 49 must move to the dot-and-dash position at the right in Fig. 9 before switch 50 opens. Similarly, the switch lever 49 must move counter-clockwise to the position shown in dot and dash lines at the left in Fig. 9 before switch 50 will close. This relatively large angular movement between opening and closing positions may be of the order of 22 degrees and is deliberately made this large to protect against re-starting the spinning operation without ade quate water supply for the balance rings, as will herein after appear.

Thus it will be seen that movement of handle 45 down from upper or vertical position to lower position, as shown in Fig. 4, serves to wind up motor spring 43; and also to wind up clock spring 114, providing the latter is not already wound tight. The ratchet arrangement 112, 113 permits this action. If the spring 114 is wound tight, slip clutch 47 will simply slip. Movement of the handle 45 to lowermost position also closes the electric switch 50.

When the handle 45 is released in lowermost position, the spring motor 90 operates to move the handle upwardly under the control of the clockwork. The torque exercised by motor spring 90 is not sufficient to overcome the resistance of slip clutch 47. lust before the handle 45 reaches its upright limiting position, switch 50 opens, shutting down the machine. At any time the operator is free to push the handle 45 upwardly to hurry the cycle; it is only necessary to overcome thel resistance of slip clutch 47 The sequence of water-controlled operations of the timing valve is as follows (see Figs. l2 to 18).

With the handle 45 in lowermost position (as shown in Fig. l2) plate ports 80 and 82 are in substantial alignment with iill port 66 and rinse port 67 respectively. Water from supply conduit 14 passes through these aligned ports and into supply spout 32 to ill the machine. This condition obtains until the handle 45 moves 32 degrees (l0 and 2/3 min.) or to the position shown in Fig. 13, which indicates the beginning of the wash period.

At the beginning of the wash period, the ports are all out of register as shown in Fig. 13, and no water flows through the timer valve. The basket partakes of its gyratory action, washing the clothes for its period of 12 minutes corresponding to 36 degrees. At the end of the washing period, the handle 45 is in the position shown in Fig. 14, which is the beginning of the rinsing period.

For rinsing, rinse ports 67 and 81 come into register; this allows a limited iiow of water through the valve, depending upon the setting of adjustable needle valve 70. This valve is adjusted to permit the desired amount of rinse water to flow through, depending upon the pressure of the water supply. The basket continues to gyrate and rinse water continues to flow all during the time that the handle 45 moves through 44 degree angle (14 and 2/3 min.) until it reaches the position shown in Fig. l5, which indicates the end of the rinse period and the beginning of the spin period.

At the beginning of the spin period, all water flow through the valve is stopped but water pressure is supplied through the spin ports 68 and 82 to the servomotor 21; this shifts the machine to spinning position. This expels the water out of the clothes. This may continue for a five minute period corresponding to l5 degrees, until the handle reaches position shown in Fig. 16.

At the end of the spin period, the spin ports 68, 82 go out of register; bleeder 34 relieves pressure from the servomotor 21 which operates to bring the washing machine back to gyratory agitating position. The handle 45 will continue to rotate through an additional 3 degrees, as shown in Fig. 16 to the position shown in Fig. 17, to operate the electric switch 50, which turns off power from the entire machine.

Operation and continents The user may operate the timer and washing machine as follows. She puts the clothes in the basket 16 and opens hot water faucet 10 (Fig. l). This puts hot water pressure on the control valve of the timer T. She then throws the handle 45 from the off position shown in Fig. 17 to the lowermost position marked fill on dial 53. As the machine lls with hot water, the user adds the desired soap, water softener or other detergent directly into the top of the basket 16.

When the basket is partly filled with water, the machine may be started by plugging the cord 24 into the wall socket. The cover on the machine may then be closed if desired, or left open. Plugging in of cord 24 starts motor 20 running and, at the same time, starts the gyrating action on the basket 16 to agitate the contents since the servomotor 21 is normally in agitate" position.

When the user finds sufficient water in the basket to wash the clothes, depending upon the size of the load, she turns off the hot water faucet 10 and raises the handle 45, setting it at the number of minutes on dial 53 it is desired to wash the particular batch involved. She will then open the cold water valve 11 an amount depending upon the desired temperature for the rinse Water, and also the hot water valve 10 is desired. Or, if she prefers to save hot water, she may keep the hot water valve 10 closed. From this point on, the machine is fully automatic.

The machine will wash the clothes the number of minutes called for; the machine will then supply a suflicient rinse of cold or tempered water for the number of minutes for which the timer is designed. As above indicated, this may be in the order of fteen minutes. The basket continues to exercise its gyratory agitating movement during the rinsing period. The rinse water dilutes the wash water in the basket, causing it to overflow the basket into the tank. lt also slowly cools the wash water. The supplying of rinse water for fifteen minutes finally displaces the wash water entirely, the rinsing period ending with the basket illed with pure water.

At the end of the rinse period, the timer applies water pressure to servomotor 21, which shifts the machine to centrifugal drying position. This causes the basket to spin the water out of the clothes to the usual dry condition in a iinal live minute spin, after which the electric switch will open and the machine will stop.

The operator may then close the cold water valve 11 and also the hot water valve 10, if open, and if no more washing is to be done, she will then pull out the electric plug, disconnecting the machine from the power supply.

The timer does not interfere in any way with manual operation of the machine, should that be desired. The operator can, at any time, shift the handle 45 to any of the four positions, ll, wash, rinse or spin, and, by manipulating the hot water valve 10 and cold Water valve 11, introduce the desired temperature water into the machine.

The supply of rinse water to the machine without first expelling the wash water has certain advantages. It conserves heat in the wash water. For example, seven gallons of 130 degree wash Water, when mixed with thirty gallons of 70 degree rinse water, will give a iinal temperature of nearly 85 degrees at the end of the fifteen minute flush-rinse cycle. The rinse Water ows into the basket diluting the hot, soapy wash solution and overflowing it over the top of the basket. The continued agitation during the rinsing period gives additional washing action to the clothes. This loosens up all of the dirt, curds. scum, lint and other foreign matter, which may be entrapped in :the clothes after the washing operation, and llows this matter over the top of the basket.

The above timer gives -greater flexibility of operation. The length of the washing period and the temperature of the wash water may be Varied by the operator, if desired. Likewise, the temperature of the rinsing water may be varied. These items are important in the washing of rayons, for example, which require cool water, and of woolens which require only slightly warm water and should have very little friction and agitation.

As an example of an actual complete cycle, the laundry may be washed in approximately seven gallons of hot Water, with the washing time fifteen minutes for example. Following the wash period, about two gallons of tempered or cold rinse water per minute may be supplied for a ifteen minute period.

The use of the balance piston removes excessive pressure between the valve plate and .the valve body, reducing the torque required to turn the timer. At the same time, the use of a booster spring motor enables a comparatively inexpensive standard timing clockwork to be used.

The present invention greatly simplifies the construction of the usual timer used on fully automatic or semi-automatic household washing machines. merous cams and cam controlled switches. It simplies wiring and reduces the number of valves. The use of a single spinning operation reduces wear and tear on the washing machine.

Sometimes the user may wish to re-rinse the clothes or give an additional spin to the clothes after a complete washing cycle. A delay action is provided to prevent restarting the electric drive motor until the handle 45 is pulled back a predetermined number of degrees, as for example 22 degrees, to the position shown in Fig. 17. T his angle is suicient to bring the rinse ports 67, 81 back into register; thus to re-supply the machine with water to supply the balancing rings for the subsequent spinning operation.

The bleeder connection 34 provides an vadditional precaution to supply water to the balance rings during any spinning operation. Thus, any time hydraulic pressure is applied to tubing 22 for operating servomotor 21 to spin the basket, the bleeder connection 34 supplies water to the balance rings. Bleeder 34 also relieves pressure on the servomotor 21 when hydraulic pressure is removed from tubing 22.

Either the delay action for Vre-starting the machine or the bleeder connection alone may be used to insure supply of Water to the balance rings during spinning, or both these devices may be used together as shown.

As noted, the needle valve 70 is provided for adjusting the flow rate during the rinsing period. It will be understood that for any given installation, this adjustment may be made when the machine is installed, once and for all. For communities with high water pressure, the valve will naturally be open less than for communities with relatively low water pressure.

Instead of using a manually adjustable valve to control the ow of rinse water, an automatic ilow may be provided, as indicated in Fig. 19. Here theparts surrounding the rinse ports 67', 81 are given numbers corresponding to similar parts in Fig. 6, but with primes added.

The automatic rinse water How is provided by the use of a conventional How washer 126. This washer may be seated in a suitable metal cup 127, suitably secured to the margin of the port 81' on the rotary valve plate 42. As is well known, these washers are made or a soft plastic material, such as rubber; they are compressed by the water lpressure to decrease the lsize of their opening ac- It eliminates nucording Ato the amount of the pressure. Thus, for higher Water pressures, the opening is automatically reduced and vice versa; this `provides greater throttling action on rela tively high pressure water than on relatively low pressure water.

While certain novel features of the invention have been disclosed herein, and are pointed out in the annexed claims, it will be understood that various omissions, substitutions and changes may be made by those skilled in the art without departing from the spirit of the invention.

What is claimed is:

in a centrifugal extracting machine, a spin assembly .comprising an open top basket and a balancing duct, means to spin said spin assembly about its axis, said balancing duct being annular and surrounding the outer side wall of the basket and rotatable with the basket, said vduct having 4an outer wall with inwardly extending wall portions to provide an annular passage to allow balancing liquid to flow circumferentially of the duct and pile up on the side of the spinning assembly diametrically opposite the unbalanced load when the basket is spun at extracting speed, the outer side wall of said basket having a discharge section whereby liquid is discharged from .the material held in the basket into the duct when the basket is spun at extracting speed, said duct having an open section at its lower end whereby the balancing liquid drains out of the duct when the basket does not have sufiicient speed, a trame surrounding said basket, a supply conduit to supply liquid to the machine, said supply conduit being supported on said frame, a safety conduit supported on said frame leading from said supply conduit to a point associated with said balancing duct to insure a supply of safety liquid for said duct and thus avoid unbalance due to lack of balancing liquid in the event no normal balancing liquid is available in the basket to supply said duct; means for subjecting the contents of the basket to a washing operation, a hydraulically operated servomotor for initiating and maintaining the extracting operation, a main conduit connecting said servomotor and said supply conduit, said safety conduit constituting 4a bleeder connection from said main conduit, and a control valve controlling the supply of liquid from said supply conduit to said main conduit and to said safety conduit,

said Aliquid [lowing from said bleeder connection continuously while said control valve supplies hydraulic pressure `to said servornotor, said machine being in position for the extracting operation when said control valve is open, said machine being in position for the washing operation when said control valve is closed.

References Cited in the tile of this patent UNITED STATES PATENTS Number Name Date 1,604,748 lGraver Oct. 26, 1926 2,346,259 Hutchings Apr. 11, 1944 2,364,697 Daniels Dec. 12, 1944 2,382,833 Timbs Aug. 14, 1945 2,384,318 `Le Bleu Sept. 4, 1945 2,391,561 Goldhof Dec. 25, 1945 2,421,481 Collins June 3, 1947 2,461,643 Hemmeter Feb. l5, 1949 .2,471,217 Iohnson May 24, 1949 2,478,702 Moody Aug. 9, 1949 2,498,420 Hemmetcr Feb. 21, 1950 2,512,263 Archbold June 20, 1950 V2,525,781 De Reiner Oct. 17, 1950 2,534,194 Emmert et al. Dec. 12, 1950 2,538,246 Holm-Hansen Jan. 16, 1951 2,574,170 Cockerill et al. Nov. 6, 1951

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