High-pressure Washing Equipment

Abstract

High-pressure washing equipment adapted to deliver either of two cleaning fluids selectively against hard surfaces to be cleaned and having for its principal object to provide simplified controls adapted to be selectively operated to deliver a multiplicity of cleaning fluids in the form of a high-pressure and high-velocity spray, said equipment incorporating a sequential valve.

Description

BACKGROUND OF THE INVENTION

1Field of the Invention

This invention relates to high-pressure washing equipment involving pressures of several hundred pounds per square inch, and more particularly relates to a system wherein the multiplicity of switches, relays, solenoids and related equipment are eliminated and a more trouble-free and positive control is provided.

2. Description of the Prior Art

In high-pressure cleaning apparatus using fluids ejected at relatively high pressure and, in particular, to cleaning apparatus which delivers a multiplicity of different cleaning fluids, such apparatus has required complicated electrical systems including relays, solenoids, and related wiring, as exemplified by the Techler et al. patents, U.S. Pat. No. 3,246,845 and U.S. Pat. No. 3,118,610. Failure of such equipment required extensive repairs, and loss of production.

Similar systems are shown in the following patents: R. R. Curtis et al., U.S. Pat. No. 3,369,705; K. J. Heinicke et al., U.S. Pat. No. 3,322,350; and H. A. Poppitz, U.S. Pat. No. 3,433,417.

SUMMARY

As contrasted with the prior art, described above, the present invention provides a cleaning apparatus for multiple fluids which are to be ejected under high pressure, particularly for use in automobile washing and similar applications such as the cleaning of engines, machinery and the like, which has a positive control that is triggered hydraulically at the nozzle of a control gun, and which eliminates most of the control circuits including relays, solenoids, etc. for operating the system of which the apparatus is a part.

It is an object of the present invention to provide a cleaning apparatus having a positive mechanical control for the flow of cleaning fluids, requiring only the availability of conventional 110-volt AC electrical power, and a water supply at conventional distribution pressure of 35- 90 pounds per square inch for its operation.

It is a further object of the present invention to provide a cleaning apparatus having a wide range of control of the proportions of two cleaning fluids to be discharged by the apparatus.

It is a further object of the present invention to provide a cleaning apparatus having an accurate means for controlling the ratio of one cleaning fluid to another introduced into the apparatus from separate fluid-supply sources.

It is a further object of the present invention to provide a cleaning apparatus which eliminates the danger of electrical shock to the operator by eliminating all electrical wiring at the operator-manipulated discharge nozzle.

A further object of the present invention is to provide a cleaning apparatus of the type referred to in which the pump, which raises the pressure of the cleaning fluids to elevated, discharge pressure, cannot be operated unless the supply-discharge gun is operating.

My invention also includes certain other novel features of construction which will be more fully pointed out in the following specification and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of my flow system including the principal elements of my improved controls;

FIG. 2 is a detail showing of the sequential valve and the unloader valve, illustrating the relationship and cooperation between these elements;

FIG. 3 is a sectional top view with parts broken away showing the elements of the sequential valve;

FIG. 4 is a sectional side elevation with parts broken away showing the sequential valve cooperating with the lever by which it is actuated in response to the movement of the piston rod on the unloader valve;

FIG. 5 is a schematic view of the unloader valve showing the operating elements;

FIG. 6 is a schematic view of the injector for the soap solution;

FIG. 7 is a schematic view of a two-stage injector.

FIG. 8 is a longitudinal sectional view showing a suitable spray-head valve for my control;

FIG. 9 is a cross-sectional view of the spray head valve; and

FIG. 10 is a sectional view of the switch for starting and stopping the pump.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the drawings in detail, FIG. 1 shows a schematic illustration of the flow system, including the principal elements of the improved controls. As shown in FIG. 1, water is brought in from a tapline at pressures ranging from 35 to 90 pounds per square inch and flows through line 12, through check valve 14, through line 15 into an inlet of pressure reducer 16 where the pressure is reduced to 30 pounds per square inch. Pressure reducer 16 is a conventional pressure reducer and may be of any one of several types which are available commercially. The water then passes through conduit 17, into liquid injector 18 (FIG. 6). Injector 18 is shown in detail in FIG. 6, and is of simple construction and with no moving parts. As shown schematically in FIG. 6, a liquid under pressure enters the injector 18 through the nozzle 19 and is converted into a jetstream. This high-velocity jet and the accompanying low pressure create a flow through the suction tube 20 and into the injector 21. The mixture then flows through the diffuser 22, where pressure is recovered. A portion of the energy is imparted to the fluid drawn in through the suction tube, so the reconverted pressure cannot be as high as the supply pressure. For maximum-pressure recovery, or minimum-pressure loss, a two-stage injector may be used. (FIG. 7). The small booster stage draws in fluid at a vacuum and discharges into the intermediate pressure region of the larger second stage. In this way, approximately only one-half of the total pressure recovery occurs in each stage. Consequently, the two-stage injector can operate more efficiently at high discharge pressures.

Fluid enters the inlet 19 and issues from outlet 23 of the injector through line 23a to pump 24 which is a motor-driven pump capable of raising the pressure of the fluid (either water or soap solution) to 500 pounds per square inch. The fluid then passes through line 25, through unloader valve 26 (FIGS. 1 and 5) to a flexible high-pressure line, through conduit 27 extending to a spray head 28, having an elongated tube 29 extending to a spray nozzle 29a. The head 28 has a handle 30 for directing the spray from the nozzle against the surfaces to be cleaned and a manually operable lever 31 projects from the head 28 adjacent to the handle 30 for operating a valve contained within the head. A suitable valve for the head 28 is shown in FIGS. 8 and 9. As shown, the lever 31 is pivotally connected to the head 28 by a pin 32 and a plunger 33 is operatively connected to the lever 31 at one end and has a rod 32a extending axially from the plunger and a valve closure member 34 is mounted on the opposite end of the rod 32a extending axially from the plunger and a valve closure member 34 is mounted on the opposite end of the rod 32a. An annular seat 35 is formed in a valve end fitting 36 for the closure member 34. This valve is normally biased toward closed position by a coiled spring 37 which surrounds the plunger 33 and is confined between an annular flange formed thereon and the spray head housing. As shown in FIG. 9, the closure member 34 is hexagonal in shape so that when the valve is opened by operation of the level 31, the fluid passes the member 38 through a cylindrical bore in the head 28a containing the member 38. Assuming unloader valve 26 is in the open position and the trigger 31 of spray head 28 is closed, there will be no flow out of the spray head and the back pressure on the line 40 will operate against the piston 62 of the unloader valve 26 to maintain the unloader valve in the open position. As valve 26 is opened, fluid is recirculated to bypass line 43 back through conduit 23a to pump 24. As the trigger 31 of the spray head 28 is opened, the pressure is released on the piston 62 of unloader valve 26 so that valve 21 is closed, thus permitting the flow of fluid through the unloader valve 26 and the spray head 28 under 500 pounds pressure per square inch.

Unloader valve 26 has a bypass port 45 connected to a bypass conduit 43 disposed in continuous communication with the pump-inlet conduit 23a and a branch 67 of the bypass conduit 43 extends from passage 63 to a ball-type check valve consisting of a closure member 68 to normally close the passage 67 at an annular seat 68a. This check valve prevents flow from the passage 67 to the port 45 when the member 68 is closed at its seat 68a.

Pressure-responsive means are provided for unseating the ball-closure member 68 and opening flow through the bypass passage 67 and conduit 43 when the pressure in the flexible conduit 27 exceeds a predetermined value. For this purpose a chamber 60 in the housing 62 is disposed in continuous communication through a passage 61 with the passage 63 and port 65. Within the chamber 60, a piston 90 is movable axially and carries a piston head 91 and a pin 92 projecting beyond the piston for engagement with the check ball or closure member 68. Projecting axially from the piston 90 through an opening in the housing 62 is a stem 93 carrying exteriorly of the housing a spring-confining washer 94 and a spring-tension-adjusting nut 95 for holding a coiled spring 96 under compression. This is a stiff spring 96 which retains the piston 90 in its retracted position against a predetermined high pressure in the chamber 60. When pressure in excess of this predetermined pressure develops in the chamber 60 above the piston 90, the latter forces the pin 92 downwardly to unseat the ball valve member 68 and allow flow from the outlet of the pump through the conduit 25, passages 67 and 43, and conduit 23a, to the pump inlet. This unloader valve prevents damage to the pump when flow through the spray head 28 is cut off.

As shown in FIGS. 1, 2, 3, 4 and 5, as piston 90 is moved axially, stem 93 moves downwardly thus actuating lever 75 of the sequential valve assembly and thereby moving ratchet wheel 76 through latch 77. Ratchet wheel 76 is mounted on the valve stem shaft 96, and is secured by the setscrew 120. This moves the valve 71 through a 45.degree. angle of rotation, thus opening soap-supply line 110 and moving a soap supply through line 97 into the injector 18, and supplying soap solution to the high-pressure line. The next time the valve stem moves in response to the operation of the trigger 31, the ratchet wheel is moved another 45.degree., thus the sequential valve is closed, shutting off the flow of soap solution.

As shown in FIGS. 3 and 4, the valve body 71 has a smoothly machined tapered seat of approximately 20.degree. included angle bored through the valve body. At right angles to the valve seat and on the centerline of the valve body, the flow orifice 115 is drilled which meets tapped holes 113 to 114 for pipe fittings on each end of the valve body.

The valve stem 72 has the same taper as the valve body. An orifice 74 is drilled at right angles to the valve stem at a point that will coincide with the valve-body orifice when the stem is inserted in the tapered valve seat. Another orifice 73 is drilled through the valve stem which will intersect orifice 74 at 90.degree. from it.

An eight-point ratchet wheel 76 is mounted on the valve stem shaft and is secured by the setscrew 120.

The valve stem 96 with ratchet wheel 76 is held in place by the compression spring 79 and pressure plate 111.

The valve 71 is opened or closed by a 45.degree. rotation of the valve stem. The rotation of the valve stem is accomplished by the vertical motion of the lever arm 75 and latch 77 working as engaged with the ratchet wheel 76. Part 100a is the mounting plate for the valve assembly.

OPERATION

In operation, water enters from a city waterline through a ball-check valve and a pressure-regulating valve which cuts the pressure to a standard 30 pounds per square inch. From the regulator, the water flows through an injector 18 which employs the Venturi principle to induct a soap solution into the waterline. The twin-piston pump 24, driven by a 3/4-HP motor (not shown), develops 500 p.s.i. at 2 gallons per minute.

In the high-pressure line, there is an unloader valve 26. When the nozzle 29, at the end of the high-pressure line is closed, the back surge of pressure causes the unloader valve 26 to open, bypassing the 2 gallons per minute of water or soap back to the inlet line of the pump. When the unloader valve unloads, the piston in the valve travels downward against an external coil spring. A lever arm hooked to the top end of this downward-travelling piston rod, operates the ratchet wheel of the sequential valve causing it to rotate 45.degree.. This closes the valve if it is open or opens it if it is closed. As the valve is in the soap solution line which is connected to the suction arm of the injector, it either permits or prohibits the flow of soap. Thus, the valve provides both soap and rinse cycles triggered hydraulically at the nozzle by a control gun. When the nozzle is reopened, the unloader valve closes, moving the piston shaft upward, and the latch downward so that it engages the next succeeding notch in the ratchet wheel ready for the next cycle.

To adapt my invention for use in self-service carwash installations, I provide a lever-operated switch having a housing indicated generally by the numeral 180 in FIG. 10. A toggle switch 181 within the housing 180 is of the conventional type which is closed when the gun is not operating, for holding the power circuit closed. When the switch circuit is closed by the movement of lever 75, the circuit is energized and remains energized throughout the cycle of operation. As indicated in FIG. 10, upon the closing of the switch 181, the circuit is closed thereby energizing the motor. Assuming that upon the closing of the switch 181, the manual valve under control of the lever 31 at the spray head 28 is closed, either water from the inlet 12 or cleaning solution from the container 190 is drawn into the pump inlet through conduit 23a and passes through the outlet conduit 25 until the pressure in the chamber 60 rises to a point where the piston 90 is moved downwardly as seen in FIG. 5 to unseat the check-ball member 68 and open flow through the bypass passage 67, conduit 43 and pump-inlet conduit 23a.

If at the time of the closing of the switch by the movement of lever 75, the circuit is energized, water will be fed to the pump inlet, and cleaning solution will be withdrawn from the reservoir to the pump inlet and will be recirculated through the unloader valve from the pump outlet to the pump inlet as hereinbefore described. A bay area is indicated generally by the broken line 83 (FIG. 5). The automobile or other vehicle to be washed is parked in the bay area within reach of the spray head at the end of the flexible conduit 27.

It will be evident that my improved pressure washer has no electrical control switches at the handle of the spray head. The shift from supplying soap solution to supplying rinse water under pressure through the flexible conduit 27 is accomplished merely by the pressure drop in the line acting on the pressure-responsive piston 90 each time the lever 31 is released. Thus, in order to change from soap solution to rinse water at the nozzle or from rinse water to soap solution, it is only necessary to release the lever 31 and then squeeze it again.

For installations where alternating current is not available, or where it is desirable to make the washer readily portable, the pump 24 may be operatively connected to an internal combustion engine, and electric current for operating the solenoid valve, signal and pressure switch circuits may be supplied from a battery carried by the washer carriage.

Claims

I claim:

1. In a pressure washer, a power-driven pump having an inlet and an outlet connected by a flexible conduit to a spray head including a handle for directing the spray from said head, a first valve controlling flow through said head; conduit means for supplying liquid to the inlet of said pump and having a first branch connected to a source of water and a second branch connected to a source of cleaning fluid, and a second sequential valve controlling flow of cleaning fluid through said second branch to said pump inlet, the improvements which comprise a sequential valve which is opened and closed in response to the movement of the stem of an unloader valve for opening and closing the conduit supplying soap solution to the system.

2. A pressure washer, in accordance with claim 1, in which said sequential valve is operated by a lever and ratchet in response to the movement of the stem of an unloader valve which is actuated by a piston responding to the pressure upon the closing of a shutoff valve in a spray head.

3. A pressure washer, in accordance with claim 1, in which a toggle switch is operated in response to the movement of a piston stem of an unloader valve which opens and closes a circuit for operating and shutting off a motor-driven pump.