US 3246845 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
April 9, 1966 'r. w. TECHLER ETAL 3,246,845
CONTROLS FOR HIGH VELOCITY WASHING EQUIPMENT Filed June 11, 1964 5 Sheets-Sheet l A '4 |4Cl ll5V o L! j- -L.2
RELAY COIL INVENTORS 2 moms w. TECHLER RICHARD 6. THOMPS /v ATTORNEY April 19, 1966 T. w. TECHLER ETAL CONTROLS FOR HIGH VELOCITY WASHING EQUIPMENT 5 Sheets-Sheet 2 Filed June 11, 1964 52a v 7 a f; a
INVENTORS THOMAS W TECHLER RICHARD G. THOMPSON ATTORNE April 19, 1966 T. w. TECHLER ETAL 3,2
CONTROLS FOR HIGH VELOCITY WASHING EQUIPMENT Filed June 11, 1964 5 Sheets-Sheet 5 siss 32o THOMAS W. TE CHLER RICHARD 6. THOMPSON ATTORNEY United States Patent 3,246,845 CONTRQLS FOR HIGH VELOCITY WASHING EQUIPMENT Thomas W. Techler, North St. Paul, and Richard G.
Thompson, Stillwater, Minn, assignors to L & A Products, Inc, St. Paul, Minn, a corporation of Minnesota Filed June 11, 1964, Ser. No. 374,335 13 Claims. (Cl. 23971) This invention relates to improvements in high velocity washing equipment adapted to deliver either of two cleaning fluids selectively against hard surfaces to be cleaned and has for its principal object to provide simplified controls adapted to be selectively operated to deliver either of two cleaning fluids in the form of a high velocity spray.
Our invention is particularly adapted for the control of Washers having a power-driven pump, the outlet of Which is connected by a flexible conduit to a spray head and valve including a handle for directing the spray from the head and conduit means for supplying liquid to the inlet of the pump from a source of water and a source of cleaning fluid, detergent solution or the like, valves being provided in the conduits to control flow of the several liquids to the pump. The pumps are usually designed to deliver the liquid to the spray head at pressures of several hundred pounds per square inch. An example of a pressure washer of this type is described in Techler patent No. 3,118,610, granted January 21, 1964.
A particular object of our invention is to provide a control for washing equipment of the class described comprising a simple manually operable valve located adjacent to the spray head or handle for directing the spray and disposed to coact with a pressure actuated electric switch responsive to changes in pressure at the pump outlet to selectively supply either of two fluids to the pump inlet, e.g., water and a cleaning fluid or detergent solution.
Our invention also includes certain other novel features of construction which will be more fully pointed out in the following specification and claims.
Referring to the accompanying drawings which illustrate, by Way of example and not for the purpose of limitation, a preferred embodiment of our invention:
FIGURE 1 is a schematic illustration of our flow system, including the principal elements of our improved controls, exclusive of the electric circuits;
FIG. 2 is a schematic wiring diagram showing the electrical elements;
FIG. 3 is a plan view of our machine or apparatus with the wiring omitted;
FIG. 4- is a longitudinal sectional view showing a suitable pressure responsive switch assembly;
FIG. 4A is a vertical sectional view showing details of a suitable toggle switch;
FIG. 5 is a longitudinal sectional view showing a suitable spray head valve for our control, and
FIG. 6 is a cross sectional view of the spray head valve taken on the line 6-6 of FIG. 5.
As shown in FIG. 1 a power-driven pump 10 has an inlet which is adapted to be supplied with liquids through a conduit 11 connected to a valve manifold 12. A first branch passage 13 is formed in the manifold 12 and adapted to be connected to a source .of water or other liquid at an inlet port 14. Ordinary tap water may be supplied to the port 14 through a hose connected to a fitting 14a (FIGS. 1 and 3). An electrically energizable valve indicated generally by the numeral 15 is interposed in the passage 13 to control the flow of water from the port 14. As shown, the valve 15 is biased to normally close the passage 13 and has an electrically energizable solenoid coil 16 arranged in conventional manner to open the valve when energized. Solenoid plunger 16a is connected to a valve closure member 15a and the plunger is spring biased normally to retain the valve in closed position.
A branch passage .17 is formed in the manifold 12 and is arranged to be supplied with a cleaning fluid, e.g., a soap or detergent solution from a source which may comprise a container 18 which is vented to atmosphere. The flow of liquid from the container 18 to passage 17 is under control of a valve 19 which is preferably a check valve having a bias toward normally closed position to prevent flow of liquid from the passage 17 to the container 18 when fluid in the passage 17 is under pressure substantially above atmospheric pressure. Liquid is drawn into the passage 17 and conduit 11 when pressure substantially below atmospheric pressure is created in this pump inlet.
From the outlet of the pump 10 a conduit 20 extends to a port 21 formed in an unloader valve housing 22 (FIGS. 1 and 3).. A passage 23 extends from port 21 in the housing 22 to a check valve 24 and thence to an outlet port 25. From this port a flexible conduit 2-6 extends to a spray head 27 having an elongated tube 28 extending to a spray nozzle 23a. The head 27 has a handle 29 for directing the spray from the nozzle against the surfaces to be cleaned and a manually operable lever; 30 projects from the head 27 adjacent ,to the handle 29.
for operating a valve contained within the head. A suit able valve for the head 2-7 is shown in FIGS. 5 and 6. As shown, the lever 39 is pivotally connected to the head 27 by a pin 31 and aplunger 32 is operatively connected to the lever 30 at one end and has a rod 32a extending axially from the plunger and a valve closure member 33 is mounted on the opposite end of the rod 32a. An an nular seat 33a is formed in a valve end fitting 27a for the closure member 33. This valve is normally biased toward closed position by a coiled spring 34 which surrounds the plunger 32 and is confined between an annular flange formed thereon and the spray head housing. As shown in FIG. 6, the closure member 33 is hexagonal in shape so that when the valve is opened by operation or" the lever 36, the fluid passes the member 33 through a cylindrical bore in the head 27 containing the member Unloader valve-housing 22 has a third port 35 connected to a by-pass conduit 36 disposed in continuous communication with the pump inlet conduit 11 and a branch 37 of the by-pass conduit 36 extends from the passage 23 to a ball type check valve consisting of a closure member 38 which is biased by a spring 39 to normally close the passage 37 at an annular seat 38a. This check valve prevents flow from the passage 37 to the port 35 when the member 38 is closed at its seat 38a.
Pressure responsive means are provided for unseating the 'ball closure member 38 and opening flow through the by-pass passage 37 and conduit 36 when the pressure in the flexible conduit 26 exceeds a predetermined value. For this purpose a chamber 48 in the housing 22 is disposed in continuous communication through a passage 41 with the passage 23 and port 25. Within the chamber 40 a piston 42 is movable axially and carries a piston head 43 and a pin 44 projecting beyond the piston for engagement with the check ball or closure member 38. Projecting axially from the piston 42 through an opening in the housing 22 is a stem 45 carrying exteriorly of the housing a spring confining washer 46 and a spring tension adjusting nut 47 for holding a coiledspring 48 under compression. This is a still spring 48 which retains the piston 42 in its retracted position against a predetermined high pressure in the chamber 40. When pressure in ex- .cess of this predetermined pressure develops in the chamber 40 above the piston 43 the latter forces the pin 44 downwardly to unseat the ball valve member 38 and allow flow from the outlet of the pump through the conduit 20, passages 37 and 36 and conduit 11 to the pump inlet. This unloader valve-prevents damage to the pump when flow through the spray head 27 is cut ofi.
As shown in FIGS. 1 and 4, a pressure responsive switch actuating mechanism has a housing 59 containing a spring biased plunger head 51 which is subjected to the fluid pressure in the conduit 20 at the outlet side of the pump. The pressure is transmitted through a conduit 52 and orifice 52a to the plunger head 51 and the latter is normally retained in its retracted position by a coiled spring 53. From the inner end of the plunger head 51 a pin 54 projects in operative relation to a plunger 55 for actuating a snap switch contained in a housing 56.
As further shown in FIG. 4, the switch 56 may be of the toggle type which energizes alternately two terminals and contact is maintained in each position until the next operation of the switch. This switch, as indicated in FIGS. 2 and 4, has a common terminal 57 and terminals and contacts indicated at 58 and 59 which may be alternately energized upon movement of a movable switch member 60 from one position to the other.
The toggle switch illustrated in FIG. 4A is manufactured by Micro Switch, division of Minneapolis-Honeywell Regulator Company, F-reeport, Illinois, and is designated as Model 81PB36-H2. The movable member 60 is snapped from one position wherein it closes contact with the normally open terminal 59 to a second position wherein it closes at the normally closed contacts 58. The toggle spring is indicated at 61 and a pin for actuating the switch is shown at 62. A spring arm 63 is in continuous contact with the pin 62 and has its upper end rigidly supported in a casing 64 of dielectric material which contains the toggle switch elements.
Linkage between the plunger 55 and spring arm 63 may comprise ratchet wheels 65 and 65a disposed to be' turned by a movable pawl 66 is pivoted at 66a and biased by a spring 66b to engage the ratchet wheel 65. Ratchet wheel 65 has five teeth and 65a has ten teeth. They cannot rotate independently of the other. A lever 67 is disposed to be actuated by the plunger 55, being pivoted at 67a and retained in contact with the inner end of the plunger 55 by a spring 67b. A second pawl 68 is fixed on the lever 67 and arranged to engage the teeth of the ratchet 65a. By this linkage the toggle switch is actuated from one position to the other alternately by successive movements of the plunger 55 to the left as seen in FIG. 4.
For most installations it is feasible to use an electric motor such as that indicated at 70 for operating the pump 10. Power may be supplied from a suitable source, e.g., a 115-volt alternating current line. Referring to the wiring diagram, FIG. 2, the motor 70 and pump to which it is connected may be operated continuously. The motor may be energized under control of a relay having a coil R and contacts R-1 and R-Z. The relay coil is energized when a circuit is closed including a switch such as that indicated at 71. A branch circuit for energizing the solenoid coil 16 of the valve includes a conductor 72 and switch 56 through its contact 58. When the switch 56 is moved to deenergize the contact 58 and energize the contact 59 is closes a circuit including a signal light 73 and a conductor 74. When this light is energized the solenoid 16 is deenergized closing the water valve 15, so that the pump 10 draws soap solution from the reservoir 18 through conduit 17a, past check valve 19 and the pump feeds the solution under relatively high pressure through the conduit past the check valve 24 through passage 23 and port to the flexible conduit 26. This flow of cleaning fluid results from the alternate opening of the valve 33 in the spray head 27. Thus the high pressure solution is fed through the nozzle member 28a and may be directed against a five minute wash cycle.
A- second signal light 75 is arranged to be energized when water is being drawn into the pump inlet through the conduit 11. The circuit for energizing the light extends from the contact 58 of the switch 56 and includes a branch circuit conductor 76, the lamp 75 and conductor 74.
To adapt our invention for use in self-service car wash installations, we provide a coin-operated switch having a housing indicated generally by the numeral in FIGS. 1 and 2. A switch 31 within the housing 86 is of the conventional type which is closed when a coin is inserted in the housing slot and includes a timer (not shown) for holding the power circuit closed for a predetermined period of time. When the switch circuit is closed a light 82 is energized and remains energized throughout the cycle of operation. As indicated in FIG. 2, upon the closing of the switch 81, the circuit from L1 extending through the relay coil R is closed thereby energizing the motor 7!) through the relay contacts R-1 and R2. Assuming that upon the closing of the coin switch 81 the manual valve under control of the lever 30 at the spray head 27 is closed, either water from the inlet 14 or cleaning solution from the container 13 is drawn into the pump inilet through conduit 11 and passes through the outlet conduit 20 and passages 23 and 41 until the pressure in the chamber 4% rises to a point where the piston 42 is moved downwardly as seen in FIG. 1 to unseat the check ball member 38 and open flow through the by-pass passage 37, conduit 36, and pump inlet conduit 11.
If at the time of the closing of the coin switch the solenoid valve 15 is energized, water will be fed to the pump inlet, whereas, if the solenoid valve 15 is deenergized, 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. 1). 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 26. The indicator lights 73 and 75 are located in the bay area where the operator of the washing apparatus is kept informed by the color of the energized lamp as to which of the washing liquids are being supplied to the sprayhead. For installations of the coin operated switch control type the normally open switch 71 may be used as a test switch and another normally open switch 84 (FIG. 2) may be closed to prime the pump 10 by operating the motor 70 and closing the circuit including the solenoid 16 of the valve 12.
It will be evident that our 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 26 is accomplished merely by the pr ssure drop in the line acting on the switch 56 through the pressure responsive plunger 51 each time the lever 39 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 30 and then squeeze it again. For a typical car wash station the coin operated switch 80-81 may be set for At the start of a wash cycle the hydraulic flow circuit may be in position to deliver either soap solution or fresh water through the nozzle depending on how it was left by the preceding user.
For installations where alternating current is not available, or where it is desirable to make the washer readily portable the pump 10 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.
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, a second valve controlling flow of water from said source through said first branch to said pump inlet, and a third valve controlling how of cleaning fluid through said second branch to said pump inlet, the improvements which comprise; a by-pass conduit connecting the outlet of said pump to the inlet thereof, an unloader valve interposed in said by-pass conduit and responsive to the pressure in said flexible conduit to open said unloader valve when the pressure in said flexible conduit exceeds a predetermined value; a first electric switch; electrically energizable means for actuating said second valve; a first electric circuit including said switch and electrically energizable means, and pressure responsive means communicating with the outlet of said pump and operatively connected to said switch whereby changes in pressure in said flexible conduit resulting from alternate opening and closing of said first valve is effective alternately to supply water and cleaning fluid to said pump when in operation.
2. A pressure washer in accordance with claim 1 in which said first valve is manually operable to open passage of fluid from said flexible conduit through said spray head and is biased to cut ofl flow through said head.
3. A pressure washer in accordance with claim 1 in which said third valve is a check valve disposed to allow flow from the source of cleaning fluid to the pump and is biased to prevent flow in the reverse direction through said second branch.
4. A pressure washer in accordance with claim 1 in which said switch has contacts for alternately opening and then closing said circuit including said electrically energizable means for actuating said second valve and said pressure responsive means is disposed to alternately open and close said switch in response to changes in pressure at the pump outlet.
5. A pressure washer in accordance with claim 1 in which said first switch is of the type having contacts disposed to be alternately energized and included respectively in said first circuit for energizing said second valve and in a second circuit including signal means for indicating when said first circuit is deenergized.
6. A pressure washer in accordance with claim 5 in which said first circuit includes signal means for indicating when said first circuit is energized.
7. A pressure washer in accordance with claim 1 in which said first switch is of the two-position toggle type having means for retaining it in one position and then the other in response to pressure changes sufficient to actuate said pressure responsive switch actuating means.
8. A pressure washer in accordance with claim 1 in which said unloader valve comprises a first passage communicating with the outlet of the pump at one end and with said flexible conduit at the other end, a check valve interposed in said first passage and biased to prevent back flow from said flexible conduit to the pump outlet, a second passage forming a branch of said by-pass passage, a second check valve interposed in said second passage and biased normally to prevent flow through said bypass conduit to said pump inlet, spring biased pressure responsive means subject to the pressure in said flexible conduit and disposed to unseat said second check valve when the pressure in said flexible conduit exceeds a predetermined high value.
9. A pressure washer in accordance with claim 1 in which said unloader valve has a passage constituting a portion of said by-pass conduit and a check valve normally biased to close said passage against flow from said pump outlet to the pump inlet, and means for unseating said. check valve to open said passage in response to predetermined high pressure including a spring biased, pressure responsive piston subject to the fluid pressure in said flexible conduit.
10. In a pressure washer, a 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, a second valve controlling flow of water from said source through said first branch, a third valve controlling flow of cleaning fluid through said second branch to said pump inlet, and an electric motor operatively connected to said pump, the improvements which comprise; a by-pass conduit connecting the outlet of said pump to the .inlet thereof, an unloader valve interposed in said by-pass conduit and responsive to the pressure in said flexible conduit to open said unloader valve when the pressure in said flexible conduit exceeds a predetermined value, a first two-position electric switch having contacts for energizing first and second circuits respectively, electrically energizable means for actuating said second valve to a first position, a first electric circuit including contacts of said switch and said electrically energizable means for said second valve, a third circuit for energizing said electric motor, a third switch included in said third circuit for controlling the operation of said motor, and pressure responsive means communicating with the outlet of said pump and operatively connected to said first switch for alternately moving it from one position to the other, whereby to supply water and cleaning fluid to said pump alternately in response to the opening and closing of said first valve during continuous operation of said pump.
11. A pressure washer in accordance with claim 10 in which said spray head includes a spray nozzle and said first valve is manually operable to open passage of liquid from said flexible conduit through said spray head to said nozzle, and is biased to cut off flow through said head.
12. A pressure washer in accordance with claim 10 in which said third valve is a check valve disposed to allow flow from said source of cleaning fluid to the pump and is biased to prevent flow in the reverse direction through said second branch.
13. A pressure washer in accordance with claim 10 in which said first switch has normally open contacts which are included in said first circuit and normally closed contacts which are included in a fourth circuit, and position signal indicators included in said third and fourth circuits to be energized respectively when said normally open and normally closed first switch contacts are energized.
No references cited.
EVERETT W. KIRBY, Primary Examiner.