US3035597A - Control protection in automatic washing machines - Google Patents

Description

IC WASHING MACHINES May 22, 1962 H. J. JONES CONTRQL PROTECTION IN AUTOMA Filed Sept. 16. 1959 FIG. i

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FIG. 2

INVENI OR HERBERT J. JONES ATTORNEY Patented May 22, 1962 3,035,597 CQNTROL PROTECTION IN AUTOMATIC WASHING MACHINES Herbert J. Jones, 711 17th St., Boulder, Colo. Filed Sept. 16, 1959, Ser. No. 840,787 1 Claim. (Cl. 137-171) This invention relates to an improved apparatus for protecting the hydrostatic control tube connecting the water level control diaphragm to the low pressure region of the centrifugal discharge pump as used on automatic washing machines from soap bubbles being drawn back into the hydrostatic control tube. The soapsuds carried back by pressure equalization, are carried far up in the vertical section of the hydrostatic control tubewhere they in time settle out into segments of water alternated by segments of air and due to the capillary action of the small size of the hydrostatic control tube and the absence of pressure behind the entrapped segments of water, allows them to remain. The entrapped segments of water in the vertical section of the hydrostatic control tube gives an adverse efiect on the water level control diaphragm by imposing added resistance to be overcome by the static column of water in washtub in lifting or moving these entrapped segments of water.

Referring to the E. O. Morton Patent No. 2,592,314, you will note that the hydrostatic control tube is attached to the centrifugal discharge pump at a point adjacent to the center of the impeller which is a low pressure region. The low pressure developed by the centrifugal discharge pump at the point of attachment of the hydrostatic control tube causes the hydrostatic control tube to be under partial vacuum during the pumping cycle when the vitiated water is being removed from the tub. At the end of the pumping cycle, equalization of pressures takes place and air rushes into the low pressure region of the discharge pump by the way of the washtub and discharge pump and carrying with it water and soapsuds far back into the hydrostatic control tube. The object of this invention is to provide means to prevent soapsuds from being drawn back into the hydrostatic control tube. To consummate the object of this invention, I have assembled a combination of several parts forming an apparatus which I will hereafter designate as a bubble trap. A drawing is hereby submitted showing the bubble trap and how it is to be used in conjunction with a washtub, centrifugal discharge pump and pressure responsive spring return water level control diaphragm and being similar to that used in the E. O. Morton Patent 2,592,314.

FIG. 1 shows the bubble trap.

FIG. 2 shows the bubble trap in combination with a washing machine apparatus.

The bubble trap comprises a tank 5 which is provided with an opening 5a. This opening is accomplished by the insertion of a copper tube into the tank 5 which extends downward into tank 5 so as to leave a space at the top of tank 5 for air and a space at the bottom of tank 5 for water to be stored. A section of the copper tubing forming opening 5a extends out of tank 5 and forms a place of attachment for a plastic tube and communicates with the interior of tank 5. Opening 5b is accomplished by inserting a copper tube into tank 5 and extending it downward near the bottom of tank 5 so that it can communicate with the stored water in tank 5 and the end of the copper tube will always be submerged in the water stored in tank 5. A short portion is left projecting out of the top of tank 5 so that a plastic tube can be connected to and communicate with the water stored in tank 5. Opening 5c is accomplished by inserting a copper tube into the top of tank 5 and is even with the underside of the top of tank 5. A portion of the copper tubing projects out of tank 5 so as to provide a place to attach a plastic tube thereto. At the point of insertion of 5a, 5b, and 50 into tank, which is of copper, the outside of the copper tubes are soldered to the tank 5 and made secure against leaks.

The operation of the bubble trap depends upon a stand-pipe 7 which is attached to the opening 50 and comprises a plastic tube and extends to an altitude well above the Water source which the bubble trap is in communication with and is a part of the bubble trap. Standpipe 7 can communicate freely with the inside of tank 5 and the other end of which extends to a higher elevation is left open to atmosphere and can communicate freely with the top of washtube 2. Realizing that this bubble trap can assume many shapes and sizes as well as being made of many suitable materials, the applicant chooses to be free to select any materials for construction of the bubble trap and determine the shape and size.

Referring to FIG. 2, I will explain the manner of incorporating the bubble trap 5 with the automatic controls of the washing machine and how it operates to protect the hydrostatic control tubes 4 and 6 from interference by soapsuds. The bubble trap is interposed between the centrifugal pump 3 and the pressure responsive water level control diaphragm 8. The bubble trap is connected and communicates with pump 3 by a short section of plastic tube 4 connected to and communicates with bubble trap 5 through its opening 5a. The water level control diaphragm 8 is connected to the bubble trap 5 by being connected to the opening 5b by the hydro static compression tube 6 and can communicate freely with the entrapped Water retained in the bubble trap 5. A stand-pipe tube 7 is connected to the remaining opening 50 and is of variable length and must extend to a higher altitude than the water which the bubble trap 5 is communicating with. Stand-pipe 7 is open at its elevated end to atmosphere and may be connected to and communicate with the top of the washtub 2. The position occupied by the bubble trap in relation to the centrifugal discharge pump 3 is shown in FIG. 2 wherein it should be of the same elevation.

The operation of the bubble trap will be explained by assuming that the washtub 2 is filled with its normal load of vitiated water and the cycle for discharging the vitiated water is to begin. At this time Water occupies the space in the centrifugal discharge pump 3, the connecting hydrostatic tube 4, all the space inside of the bubble trap 5, the space inside stand-pipe 7 to an altitude of that of the wash water in washtub 2, and the space in hydrostatic tube 6 which is not occupied by compressed air. The compressed air in the hydrostatic tube 6 which is produced by the weight of the column of water with which the tube is communicating is impressed on the water level control diaphragm causing it to move to a position enabling the master timer (not shown) to start the discharge pump 3 and the cycle for discharging the vitiated water from the washtub begins. All of the water occupying the spaces in the hydrostatic tube 4, the standpipe 7, the hydrostatic compression tube 6 and the space in the bubble trap above the bubble trap opening 5a is returned to the centrifugal discharge pump 3. At this time all low pressure regions developed by the pumping action of the discharge pump 3 are vented to atmosphere by the way of the stand-pipe 7 which is in direct communication with atmosphere. The results that my invention accomplishes at this time are venting the hydrostatic control tubes 4 and 6, the low pressure region in the centrifugal discharge pump 3 and the isolation of the compression chamber of the hydrostatic tube 6. By providing means for venting the low pressure regions between the discharge pump and the control tube 6,

soapsuds are prevented from being drawn back into the hydrostatic control tube 6. By providing a quantity of stored water in tank 5 and returning this water back to pump 3, soapsuds are washed back to pump 3. By venting to atmosphere through stand-pipe 7, the compression chamber portion of the hydrostatic control tube 6 is isolated from the influences of low pressure. By retaining a quantity of Water in the bubble trap and submerging the compression chamber portion of the hydrostatic control tube 6 in this water, a blocking action can be secured against the entry of soapsuds in the compression chamber portion of the hydrostatic control tube 6. When all pressure is released on the bubble trap, the water level control diaphragm returns to its original position by spring loaded, and the next cycle begins. In the next cycle that follows, filling the washtub with wash water, all of the space in the bubble trap, the hydrostatic control tube 4, the stand-pipe 7, and the space not occupied by air in the hydrostatic tube 6 is again filled with Water. The air from these spaces is expelled to atmosphere through stand-pipe 7. As the end of the hydrostatic control tube 6 which serves as the compression chamber and communicates with the bubble trap through opening 5b is always submerged in water, a blocking action is effected against soapsuds entering this tube 6 and any soapsuds entering the bubble trap 8 during the filling of the washtub with water is expelled.

What I claim is:

In a cleaning apparatus; in combination: a Washtub of a washing machine for containing cleaning water, an inlet to the tub, an outlet from the bottom of the tub, a centrifugal pump in the outlet for removing liquid from the tub, means comprising pressure responsive diaphragm means for controlling the washing cycle, a compressed air tube connected to the pressure responsive diaphragm means for controlling the diaphragm, a bubble trap comprising a housing having a chamber, a vent pipe communicating at one end with the upper end of the chamber and at the other end with atmosphere at a point above the highest liquid level in the tub, conduit means communicating a low pressure region of the pump adjacent the center of the impeller thereof with a region intermediate the upper and lower ends of said chamber, means connecting said compressed air tube with the lower end of said chamber so that a liquid seal is always provided for said compressed air tube.

Oakley June 21, 1898 Morton Apr. 8, 1952

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