US 2604854 A
Description (OCR text may contain errors)
w. w. TAYLOR J ly 29, 1952 LIQUID PUMP Filed May 2'4 1948 2 SHEET$-SHEET 1 wvm MM NM I N V EN TOR. [Ila/fer! 671/01 QQ ,4 T TOR/V5 Y W. W. TAYLOR July 29, 1952 LIQUID PUMP 2 SHEETS-SHEET 2 Filed May 24, 1948 INVENTOR.
Patented July 29,. 1952 UNITED. STATES PATENT OFFICE 7 2,604,854 V i v LIQUID PUMr Walter was, Oakland, Calif. -Application May .24, 1948, Serial No. 28,775
The present invention relates to improvements in cleaning machines and has particular reference to cleaning machines intended particularly for use in connection with motor vehicles, tractors, industrial machinery and similar apparatus.
Machines of this character comprise in their general features a coil, a hose connection attached to the coil and terminating in a nozzle at the free end thereof, means for heating the coil, a thermostat control for the heating means, a pump for forcing water through the coil, and control means for the flow of the water.
The present invention is particularly directed to the control means for the flow of Water or other liquid through the cleaning machine.
It has been heretofore proposed to use for this purpose a pump with a capacity greatly in excess of the amount actually used by the cleaning machine and to use a special control valve in' the exhaust line adapted to be set for the volume and pressure actually desired, with means for lay-passing the surplus water back to the intake side of the pump.
In the present invention it is proposedto use an arrangement whereby the entire output of the pump is forced throughthe coil, and a control means is provided for the intake of the pump so that the amount admitted to the pump is equal to and controls the amount forced through the coil. Y
This arrangement allows of the use of a smaller pump, it simplifies the construction of the entire cleaning machine, eliminates the use of specific, rather expensive control elements, eliminates the use of the by-pass, allows of positive feed of a predetermined amount of water through the coil regardless of pressures within the coil, and results in smoother running of the entire system.
For the purposes of this invention it was necessary to develop a specific pump, and it is a further object of the present invention to provide a pump the output of which is controlled by a valve disposed on the intake side of the pump.
If a conventional pump 'were thus controlled by limiting the intake, the piston or diaphragm would create a vacuum in the pump chamber which would tend to vaporize part of the liquid and which would result in vapor lock.
In the present invention it is proposed to overcome this difficulty by providing a pump having a variable stroke, in which the suction stroke automatically adjusts itself to the amount 'of liquid available'so as to fill the chamber without creating a vacuum. j r
Further objects and advantages ofmy invention will appear as the specification proceeds, and the novel features of my invention will be fully defined in the claims attached hereto.
The preferred form of my invention is illustrated in the accompanying drawing, in which Figure 1 shows a schematic View of the cleaning machine of my invention as a whole,
Figure 2, a longitudinal central section through a pump used in connection with the same, and
Figure 3, a similar section taken at a right angle to that of Figure 2'.
While I have shown only the preferred form of my invention, I wish to have it understood that various changes and modifications may be made Within the scope of the claims attached hereto without departing from the spirit of the invention.
Referring to the drawings in detail, my cleaning machine illustrated in Figure 1 resembles in many respects the machine described in' Patent Number 2,295,228, issued to J. F. Malsbary and myself on September the 8th, 1942, and the abovepatent is hereby referred to for the explanation of various details not forming a particular part of the present invention.
The machine comprises in its principal features a coil I suitably housed as at 2 and connected at its discharge end to a hose 3 terminating in a nozzle 4 having a relatively small orifice by means of a pipe 5 having a suitable manipulating handle 6, the hose being controlled by means of a valve hand a gauge 8 being provided in the coil outlet to give a reading of the pressure in the latter.
A cleaning liquid is forced through the coil by means of a pump 9, the discharge ID of which connects with the upper end ll of the coil through a pipe l2. The pump draws on two tanks [3 and I4, the former being a solution tank and the latter a water tank. Suitable means. not illustrated, are provided for maintaining the liquid in the two tanks at a desired level. The water tank is connected to the pump intake through a pipe I5, and the solution tank is connected to the pump intake through a hose-I6 controlled by a valve H. The dischargeend of the coil is preferably connected to the solution tank through a branch pipe 17" controlled by a valve I8 so as to .allow the coildischarge to be used for stirring and agitating the mixture in the solution tank.
The coil may be heated by any suitable means, which is here illustra'ted'as comprising a furnace l9 receiving an air blastthrough ,a conduit 20 and fuel through apipe .2l controlled by a valve 22. A suitable thermostat arrangement 23 substantially similar to that disclosed in the patent is used to allow the furnace feed to be controlled by the temperature prevailing in the lower portion of the coil, the thermostat being adjustable to respond to different degrees of heat by means of a handle 24.
The principal object of the present invention is to providev a simple control for the amount of liquid forced through the coil and to arrange the control in such a manner that any desired definite amount of liquid may be passed through the coil regardless of the pressure prevailing in the latter. provide an adjustable pump operable for increasing or decreasing the amount of liquid forced through the coil and out of the nozzle wherebythe discharge from the nozzle may be varied to range from live steam to a solid column of water while operating at a constant temperature. of say 320 Fahrenheit.
It is further proposed to. place the control, on the intake side of the pump so asto allow the amount of water or liquid admitted to the pump to be increased and decreased at wilL For this purpose, I have developed the pump illustrated in detail in Figures 2 and 3. This pump is of the diaphragm type and comprises a pump chamber 26 having an intake 21 and an exhaust I with a delivery valve 29. The intake includes a manifold connecting with two branches 30 and 3!, each of which is provided with a suction valve, 32-43, and the intake is formed with a valve seat 34 adapted for cooperation with a manually operated valve 35 for controlling the amount of liquid which may be admitted through the two suction valves.
The pump chamber has a diaphragm 35 mountedfor reciprocating'motion, with its central, portion confined between two discs 31-38. A screw 39 holds the diaphragm and the two discs in assembled relation.
The diaphragm is reciprocated for alternating suction and delivery strokes by means of a spring 40 on one side and a cam arrangement 4| on the other side.
The spring is intended to actuate the diaphragm on the suction stroke and has one-end bearing on the inner disc 38 while the other end bears on the wall of the, chamber opposite the diaphragm. This spring is tensioned to overcome the inherent resistance of the diaphragm to the outward flexing movement and to also draw in a liquid charge through the suction valves sufficient to fill the chamber; during the time available for the suction stroke. But the spring is not sufiiciently strong to retract the diaphragm sumciently far to create a vacuum which would cause'the liquid to vaporize and to create a vapor lock.
Thus the retracting movement of the diaphragm depends upon the amount of liquid available for filling the chamber during'the period of the suction stroke. If. the valve. 35- is fully open, the diaphragm will retract completely, that is, as far as the cam arrangement on. the other side will allow it to go; But when the valve 35 is partly closed and limits the amount of liquid that may be drawn in during the period of the suction stroke, the suction stroke of the diaphragm will be limited to theextent of'drawing the available liquid into the chamber but will not go beyond this limit which would tend to create a vacuum. In this manner the retracting movement of the. diaphragm is made It is proposed for this purpose to variable and is controlled by the amount of liquid available during the suction stroke.
For the compression or delivery stroke I use the cam arrangement 4| which is detached from the diaphragm and which allows the suction stroke to vary in response to variations in the amount of water admitted. The cam arrangement includes a shaft 42 mounted on the opposite side of the diaphragm and in spaced relation thereto, the shaft being supported in suitable bearings 43. Opposite the diaphragm the shaft is formed with an eccentric cam 44 which latter has a bearing 45 with inner and outer races 46-41 mounted thereon. A ring 48 is secured upon the outer race and is made to periodically advance the diaphragm for compression strokes while allowing the diaphragm to retract in the intervening periods for the suction strokes.
The bearing 45 is introduced principally for the purpose of allowing the ring 48 to remain substantially stationary while contacting the diaphragm and to thus eliminate friction, but for the purposes of explaining the operation, the entire cam arrangement may be considered a cam having a high side and a low side. The low side of the cam will determine the maximum limit to which the diaphragm may retract.
When the valve 35 is fully open so as not to interfere with the capacity of the suction valves, a full charge will be drawn into the pump chamber on each suction stroke and the diaphragm will remain in contact with the cam at all times, being advanced periodically and allowed to retract in the intervals. But when the valve 35 is partly closed so as to limit the supply available during a suction stroke period, the diaphragm will retract only sufliciently to accommodate the limited supply of liquid, without creating a vacuum, and under these conditions the low side of the cam will remain out of contact with the diaphragm while the high side will periodically strike the diaphragm for expelling an amount of liquid equal to that taken in during the suction stroke. This amount of liquid will be discharged positively, since the chamber is always filled to capacity, and will be discharged regardless of any changes in pressure opposing the pump discharge.
Thus, with the two suction valves connected to the solution and water tanks l3 and I4 respectively, with the discharge valve connected to the coil, through pipe l2 and with an orifice of a given size in the nozzle 4, and with the thermostat 23 set for a certain temperature, the characteristics of the jet emanating from the nozzle may be entirely controlled by operation of the valve 35. If the ejection of a solid body of hot water is desired, the valve will be opened for relatively free flow of liquid so as to maintain a solid and compact body of liquid in the coil at the selected temperature. When ejection of steam is desired, the operator will manipulate the valve to restrict the inflow so as to turn all or part of the liquid in the coil into steam at the selected temperature, and any intermediate nozzle discharges may be obtained by proper manipulation of the. valve. In each case the pump will positively force a given amount of liquid through the coil, depending entirely. upon the setting of the valve 35 and regardless of opposing pressures developed in the coil.
While the cleaning machine described in the Malsbary et al. patent hereinabove mentioned has been very successful and is being usediextensively, it will be seen that the present machine, used under conditions to which it is adaptable, is simpler in construction and more economic in operation since the pump is called upon to pump only the exact amount of liquid required for a given purpose, which allows the capacity of the pump to be greatly reduced and results in a great saving of power.
The shaft 42 may be driven in any suitable manner, as by an electric motor 50 and a belt drive 5!.
It is apparent that where individual control of the two liquids entering through the suction valves 32 and 33 is desired, the common control valve 35 may be omitted, and individual control valves of the same character may be placed in the intake pipes ahead of the suction valves 32 and 33.
I claim: 1
1. In combination, a pump having a pump chamber with an intake port and an outlet port, a delivery valve for the outlet port, a manifold on the pump and communicating with the intake port, a liquid conduit connected to the manifold and having a suction valve therein, and a manually operable valve for the intake port, the pump having a reciprocable piston, power-operated means for advancing the piston into the chamber to a definite point for exhausting liquid through the outlet port, and spring means for retracting the piston for sucking a liquid charge into the chamber through the intake port, the spring means being tensioned to increase the volume of the pump chamber only by the amount necessary to accommodate the liquid admitted by the manual valve at any given valve setting.
2. In combination, a pump having a pump chamber with an intake port and an outlet port, a delivery valve for the outlet port, a manifold on the pump and communicating with the intake port, a plurality of liquid conduits connected to the manifold and having suction valves therein, and a manually operable valve for the intake port, the pump having a reciprocable piston, power-operated means for advancing the piston into the chamber to a definite point for exhausting liquid through the outlet port, and spring means for retracting the piston for sucking a liquid charge into the chamber through the intake port, the spring means being tensioned to increase the volume of the pump chamber only by the amount necessary to accommodate the liquid admitted by the manual valve at any given valve setting.
3. In combination, a pump having a pump chamber with an intake port and an outlet port, a delivery valve for the outlet port, a manifold 0n the pump and communicating with the intake port, a plurality of liquid conduits connected to the manifold and having suction valves therein, and a manually operable valve for the intake port, the pump having a reciprocable piston, poweroperated means for advancing the piston into the chamber to a definite point for exhausting liquid through the outlet port, and spring means for retracting the piston for sucking a liquid charge into the chamber through the intake port, the spring means being tensioned to increase the volume of the pump chamber only by the amount necessary to accommodate the liquid admitted by voir and being free of any connection to any other fluid source, a suction valve in said conduit open during the suction stroke and closed during the delivery stroke of the diaphragm, a delivery valve for said outlet port closed during the suction stroke and open during the delivery stroke of said diaphragm, a manually operable valve in said conduit for controlling the flow through said conduit into the pump intake,
'means disconnected from and engageable with said diaphragm and operable to effect the delivery stroke thereof, and spring means engaging said diaphragm and having a spring constant of such magnitude as to effect variable suction strokes of the diaphragm'depending upon the quantity of liquid admitted by said manually operable valve.
5. A liquid pump apparatus comprising a pump casing having an intake-port, an outlet port and a diaphragm mounted for alternating suction and delivery strokes, a liquid supply reservoir, an inlet conduit providing the sole means connecting said casing intake port with said liquid supply reservoir and being free of any connection to any other fluid source, an outlet conduit for said outlet port, heating means for raising the temperature of th liquid in said outlet conduit, creating variable: pressures therein, a suction valve in said inlet conduit open during the suction stroke and closed during the delivery stroke of the diaphragm, a delivery valve for said outlet port closed during the suction stroke and open during the delivery stroke of said diaphragm, a manually operable valve in said conduit for controlling the flow through said inlet conduit into the pump intake, means disconnected from and engageable with said diaphragm and operable to effect the delivery stroke thereof, and spring means engaging said diaphragm and having a spring constant of such magnitude as to effect variable suction strokes of the diaphragm depending upon the quantity of liquid admitted by said manually operable valve.
WALTER W. TAYLOR.
REFERENCE S CIT ED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 2,253,152 Towler et al Apr. 19, 1941 2,295,228 .Malsbary et al. Sept. 8, 1942 2,345,614 Malsbary et al. Apr. 4, 1944 2,367,545 Udale Jan. 16, 1945 V FOREIGN PATENTS Number Country Date 733,959 France Oct. 14, 1932