Method and system for control of pressure washer functions

Abstract

Methods and systems for controlling pressure washer devices are provided. Pressure washers comprising at least one control unit and the ability to regulate functions of at least an engine of a pressure washer are disclosed. A control unit receives inputs from a user or various sensors provided in communication with the control unit, and is further capable of outputting a signal based on the inputs, the output signal operative to maintain or control the operating functions of an engine, pump, or motor.

Claims

1. A pressure washer comprising: an engine having a throttle to control an engine speed and responsive to control signals; a pump that discharges a fluid under pressure, the pump being in communication with and powered by the engine; a spray gun in communication with the pump; a control unit in communication with the engine; and a sensor in communication with the pump and the control unit, the sensor configured to measure a fluid pressure associated with the pump; wherein the control unit is in communication with the engine to control an engine function so as to change a mode of the pressure washer between a normal mode and an idle mode based on the fluid pressure measured by the sensor, the engine function comprising at least one of engine speed, fuel consumption, and air intake; and wherein the control unit is configured to change the mode of the pressure washer from the normal mode to the idle mode in response to detecting a trigger activation event generated within a defined time period by operating the spray gun, and wherein the trigger activation event is three fluid-pressure changes within the defined period of time caused by operating a trigger assembly of the spray gun.

2. The pressure washer of claim 1, wherein the control unit comprises an electronic control unit in electronic communication with the sensor and the engine.

3. The pressure washer of claim 1, wherein the spray gun is in fluid communication with the pump, and in electrical communication with the control unit.

4. The pressure washer of claim 1, wherein at least one of the engine and the pump are provided on a skid configured to be mounted in a vehicle.

5. The pressure washer of claim 1, wherein the throttle comprises an electromechanical switch in communication with the control unit to variably control the throttle.

6. The pressure washer of claim 1, wherein the control unit is in communication with a switch, the switch configured to selectively control a current to the control unit.

7. The pressure washer of claim 1, further comprising a battery coupled to the control unit to provide electrical power to the control unit.

8. The pressure washer of claim 1, further comprising a battery coupled to the control unit to provide electrical power to the control unit.

9. The pressure washer of claim 1, wherein the defined time period is two seconds.

10. A pressure washer comprising: an engine having a throttle responsive to control signals; a pump in communication with the engine, the pump being operable to pressurize a fluid; a dispensing device in fluid communication with the pump; a pressure sensor in communication with the engine to detect a fluid pressure produced by the pump; and a control unit in communication with the pressure sensor and the throttle, the control unit configured to receive and process signals from the pressure sensor and send signals to the throttle to control engine function to change a mode of the pressure washer between a normal mode and an idle mode based on a trigger activation event generated within a defined time period by operating the dispensing device, wherein the trigger activation event is detected by the pressure sensor, and wherein the trigger activation event is three fluid-pressure changes within the defined time period caused by operating the dispensing device.

11. The pressure washer of claim 10, further comprising: a temperature sensor in communication with at least one of the engine and the control unit; and a vacuum sensor in communication with the engine to detect a vacuum pressure at the engine.

12. The pressure washer of claim 10, wherein the control unit comprises an electronic control unit in electronic communication with the pressure sensor and the engine.

13. The pressure washer of claim 10, wherein the dispensing device is in fluid communication with the pump, and in electrical communication with the control unit.

14. The pressure washer of claim 10, wherein at least one of the engine and the pump are provided on a skid configured to be mounted in a vehicle.

15. The pressure washer of claim 10, wherein the throttle comprises an electromechanical switch in communication with the control unit to variably control the throttle.

16. The pressure washer of claim 10, wherein the control unit is in communication with a switch, the switch configured to selectively control a current to the control unit.

17. The pressure washer of claim 10, wherein the defined time period is two seconds.

18. A method for operating a pressure washer comprising an engine, a pump, a trigger assembly, a fluid-pressure sensor, and a control unit in communication with the engine and the fluid-pressure sensor, the method comprising: activating the pressure washer by starting the engine; initializing a loop wherein the control unit continuously monitors the fluid-pressure sensor to determine whether a predetermined trigger activation event has occurred and wherein the predetermined trigger activation event includes three fluid-pressure changes within a defined time period caused by operating the trigger assembly; based on the occurrence of the predetermined trigger activation event, providing a signal from the control unit to the engine to automatically change at least one operating function of the pressure washer to change a mode of the pressure washer to an idle mode.

19. The method of claim 18, wherein the at least one operating function of the pressure washer comprises engine speed.

20. The method of claim 18, wherein the loop is a first loop, the predetermined trigger activation event is a first predetermined event, and the signal is a first signal, and wherein the method further comprises: initiating a second loop to continuously monitor the fluid-pressure sensor to determine whether a second predetermined event has occurred, wherein the second predetermined event comprises a 25% change in a fluid pressure produced by the pump; and based on the occurrence of the second predetermined event, directing a second signal from the control unit to the engine to automatically change the mode from the idle mode to a normal mode.

21. The method of claim 18, wherein the control unit comprises an electrical control unit in communication with the fluid-pressure sensor and the engine.

22. A pressure washer, comprising: a pump configured to discharge a fluid; a trigger assembly operatively coupled to the pump to control the fluid discharge; an engine operatively coupled to the pump to power the pump; a sensor in communication with the pump; and a control unit operatively coupled to the trigger assembly and the engine to control a speed of the engine; wherein the control unit is configured to change the engine speed from a normal speed to an idle speed in response to a trigger activation event generated within a defined time period by the trigger assembly, and wherein the trigger activation event is detected by the sensor, and wherein the trigger activation event is three fluid-pressure changes caused by operating the trigger assembly.

23. A pressure washer, comprising: a pump configured to discharge a fluid; a trigger assembly operatively coupled to the pump to control the fluid discharge; an engine operatively coupled to the pump to power the pump; a sensor in communication with the pump; and a control unit operatively coupled to the trigger assembly and the engine to control a speed of the engine; wherein the control unit is configured to change the engine speed from a normal speed to an idle speed in response to a trigger activation event generated within a defined time period by the trigger assembly; wherein the trigger activation even is detected by the sensor; and wherein the trigger activation event is three fluid-pressure changes caused by operating the trigger assembly, and wherein the defined time period is two seconds.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a perspective view of a pressure washer according to one embodiment of the present disclosure.

(2) FIG. 2 is a perspective view of a trailer mounted pressure washer according to one embodiment of the present disclosure.

(3) FIG. 3 is a schematic wiring diagram according to one embodiment of the present disclosure.

(4) FIGS. 4A and 4B are flow charts of a method of using an electronic control unit in accordance with one embodiment of the present disclosure.

(5) To assist in the understanding of the present disclosure the following list of components and associated numbering found in the drawings is provided herein:

(6) TABLE-US-00001 Table of Components Component # Gun 2 Engine 4 Pump 6 Frame 7 Hose 8 Wheels 9 Trigger Assembly 10 Frame 12 Wheels 14 Tow Hitch 16 Trailer 17 Tank 18 Side Tanks 20 Hose Reel 22 Hose 24 Pump 26 Engine 28 Vented Panel 30 Heater Module 32 Sub-Frame 34 Rails 36 Heater 38 Header Tank 40 Heat Exchanger 42 Control Panel And Status Indicator 44 Hoses 46 Hoses 48 Buffer Tank 50 Rear Panel 52 Battery 54 Engine 56 Microprocessor Control Unit 58 Water Transducer 60 Temperature Sensor 62 Vacuum Gauge 64 Speed Control Relay 66 Speed Control Switch 68 Pressure Washer 100 Trailer Mounted Pressure Washer 200

DETAILED DESCRIPTION

(7) Referring now to FIG. 1, a pressure washer 100 comprising a gun 2 in shown. FIG. 1 illustrates one possible pressure washer 100 that employs control features according to embodiments of one disclosed system and as shown and described herein. As one of ordinary skill will recognize, the systems described herein are suitable for use with most pressure washers that output a pressurized liquid. As such, the disclosure is not limited to pressure washer 100 illustrated in FIG. 1 or trailer mounted pressure washers 200 illustrated in FIG. 2.

(8) The pressure washer 100 of the depicted embodiment comprises a hand movable mobile pressure washer that includes a trigger-actuated gun, wand, or tool, simply referred to as gun 2. Pressure washer 100 also comprises an internal combustion engine 4 and a pump 6 mounted to a chassis or frame 7. The frame 7 comprises at least one wheel 9 to facilitate movement of the device 100. The device 100 comprises an engine 4 that drives a pump 6. The pump 6 draws fluid, typically water, from a source (e.g., an onboard reservoir, a garden hose, an external tank, etc.) and selectively delivers the fluid to the gun 2 via a hose 8, under pressure. The gun 2 includes trigger assembly 10 that allows a user to selectively discharge a flow of water from the gun 2. Typically, a user actuates the trigger assembly 10 to open a valve (not shown) and begin the discharge of high-pressure fluid. When the user disengages trigger assembly 10, the valve closes, and fluid flow is inhibited from exiting the gun 2.

(9) FIG. 2 is a perspective view of a pressure washer 200 according to another embodiment of the disclosure and wherein the pressure washer 200 comprises a trailer-mounted pressure washer. The pressure washer 200 comprises a chassis or frame 12 having wheels 14 and a tow hitch 16 to form a trailer or towable unit 17. A cold water tank arrangement is supported by the frame 12, and comprises a front container or tank 18 (with respect to the normal travel direction of the trailer 17 when towed by means of tow hitch 16) and two side containers or side tanks 20. At the front end of the trailer 17, i.e., the end towards tow hitch 16, a hose reel 22 is provided to stow and carry a hose 24 to which, in use, a delivery device in the form of a gun (not shown in FIG. 2, but see gun 2 of FIG. 1) is connected. A high pressure pump 26 driven by a gas or diesel engine 28 is mounted on the main frame 12.

(10) The side tanks 20 are spaced apart from each other and define between them an accommodation space which is covered by a vented panel 30. A heater module 32 is provided and carried by a sub-frame 34 mounted on the main frame 12 by means of sliding, telescoping rails 36 which enable the heater module 32 to be moved between an access position shown in FIG. 2 by opening a rear panel 52, and a refracted operative position (not shown), in which the heater module 32 is situated in the accommodation space between the side tanks 20. In certain embodiments, the heater module 32 comprises an oil-fired heater 38, a header tank 40, a heat exchanger 42, and a control panel and status indicator 44.

(11) Also visible in FIG. 2 are inlet and outlet hoses 46, 48 connected to the heat exchanger 42 by respective quick-connect couplings or other suitable devices. A buffer tank 50 is provided and within the accommodation space beneath the vented panel 30.

(12) FIGS. 1-2 depict two embodiments of a pressure washer device that may be provided with various features of the present disclosure. However, no limitation with respect to devices or pressure washers which may employ various novel features of the present disclosure is provided herewith. It will be understood that FIGS. 1-2 are merely examples of embodiments that may comprise various features described herewith and are provided for illustrative purposes only.

(13) FIG. 3 is schematic wiring diagram of an electronic control unit auto idle system in accordance with one embodiment of the present disclosure. Referring now to FIG. 3, a battery 54 provides electrical power to an engine 56 and/or control unit 58. It will be recognized that although FIG. 3 provides an engine 56 in accordance with one embodiment, features of FIG. 3 shown and described herein may be used with other devices including, but not limited, those shown in FIGS. 1-2.

(14) In various embodiments, the microprocessor control unit 58 is in communication with at least one transducer 60, the transducer 60 being capable of monitoring at least one water pressure within the system. The control unit 58 is also provided in communication with at least one temperature sensor 62 (e.g. thermocouple), and/or a vacuum gauge 64. The transducer 60, temperature sensor 62, and vacuum gauge 64 may be electrical devices, mechanical devices, or electro-mechanical devices, as will be recognized by one of ordinary skill in the art. The microprocessor control unit 58 monitors one or more system parameters, and based on information received from one or more sensors 60, 62, 64 related to one or more parameters, the control unit 58 regulates engine function(s), such as RPM and other machine parameters. Such control is advantageous in order to save fuel, reduce emissions, control noise output and maintain a desirable pressure associated with a fluid, for example. By utilizing the various sensors, individually or in combination with each other, the pressure washer may be automatically controlled. An operator is not required to be near the unit or otherwise monitor and control the unit. The sensor feedback to microprocessor control unit 58 allows microprocessor control unit 58 to send signals to speed control relay 66 and speed control switch 68 to automatically set the RPM and other machine parameters. An operator can utilize the auto control, or manually override to return to manual control.

(15) Using a water transducer 60 to monitor water pressure and/or a vacuum gauge 64 to monitor vacuum pressure, the microprocessor control unit 58 of certain embodiments is provided to monitor changes (or lack thereof) in at least one of water pressure within the device and vacuum pressure within the engine (e.g. manifold vacuum pressure) in order to automatically adjust device functioning (e.g. engine RPM). When pressure washer functions are activated or deactivated, such as by pressing or releasing a trigger assembly of the spray gun, a signal is provided to microprocessor control unit 58 indicating such an event, and engine functioning (e.g. RPM) is adjusted accordingly. Although FIG. 3 provides a schematic of a pressure washer and control system according to one embodiment, alternative arrangements and systems are further contemplated. For example, embodiments are contemplated that do not comprise an ECU, and wherein functioning of a pressure washer device is controlled remotely, such as by one or more user-operated controls located proximal a user including on a spray gun or other remote control device.

(16) As also shown in FIG. 3, a speed control relay 66 or other electrically operated switch is provided to selectively control a circuit using a lower-power signal. The speed control relay may be automatically controlled or operated by the ECU 58 and interconnected sensors, and/or may be overridden by a user such as when a pressure washing device is intended to be operated without automatic adjustment of engine parameters or “auto-idle” features. A speed control switch 68 is preferably in communication with the speed control relay 66 to allow a user to selectively control or adjust an engine speed. In certain embodiments a lighting element is provided in communication with the battery 54, control unit 58 and/or speed control switch 68.

(17) FIGS. 4A-4B are flow charts depicting a method 400 of using an electronic control unit in accordance with one embodiment of the present disclosure. Referring now to FIG. 4A, the method begins in step 402 where a power washer is powered on and an auto-idle activation switch of the electronic control unit is engaged. In various embodiments, auto-idle activation switches of the present disclosure comprise various mechanical, electrical, and/or electromechanical switches provided to allow a user to selectively engage auto-idle features as shown and described herein. Auto-idle activation switches of the present disclosure allow a user to selectively operate a device in a standard mode (i.e. without automatic adjustment of device parameters based on working conditions), or in an auto-idle mode utilizing various features and methods shown and described herein. The program of the electronic control unit initializes in step 404, and regardless of any sensor input data, a relay contact opens and a counter begins. The time for the counter can be varied based upon operating parameters desired. Decision step 406 determines if the counter has reached a predetermined interval without a change in pressures or vacuum, thus indicating that the device is not being used. If so, the device idles down to conserve fuel and otherwise increase efficiency. If an event or change is not recognized, the counter loops and continues the monitoring process. If it is determined at step 406 that the predetermined time interval has been reached, then in step 408 the power washer idles down and the program begins a loop to monitor for a change in water pressure. Specifically, step 410 comprises a monitoring loop to determine if there is an appropriate (e.g. 25% or greater) change in water pressure within the pump, which will occur if the water trigger is pressed and washing operations are commenced, for example. If this condition 406 is not met, monitoring of the water pressure continues. If however the condition is met, the program advances to step 412 wherein the program will close a relay contact and return the idle back to an idle mode or state. The program begins a loop watching the water pressure and vacuum pressure. A counter is incremented with every loop. Typically, the cleaning process begins at this point. Control now passes to decision step 414 of FIG. 4B.

(18) Referring now to FIG. 4B, with the engine at a working idle and the relay closed, a decision step 414 is provided to monitor whether or not an activation event of the water trigger occurs. For example, in one embodiment, an activation event comprises three quick pulses of a spray gun trigger within a defined period of approximately two seconds. Such an activation event represents a clear signal from a user that the engine speed should be reduced. If such an activation event occurs, then in step 416 the relay will open and idle down the power washer. This specific triggering may be used to avoid an unintended idle down, and wherein the device requires a specific user input to induce a manual idle-down activated from the gun or otherwise distal to the engine. In certain embodiments, the activation event induces a decrease in an at least one engine speed, fuel intake, and air intake, and wherein the at least one function is reduced by approximately 20% with respect to working conditions. Control then returns to decision step 410 of FIG. 4A.

(19) If it is determined at decision step 414 that the activation event or signal (e.g. three quick pulses) of the water trigger has not occurred within a predetermined timeframe, then control passes to decision step 418. If decision step 418 determines that there is less than a 15% change in water pressure and/or less than a 20% change in vacuum pressure, thereby indicating that pressure washing activities are continuing, then the counter in step 420 will increment and control loops back to decision step 418. Such a situation indicates that a change in use of the device has not occurred.

(20) If the determination in decision step 418 is that the condition has not occurred (i.e. the result is “no”), thus indicating that washing functions have changed and an alteration to engine speed or power may need to be made, then control passes to decision step 422 to determine if an change of appropriate magnitude has occurred. In the depicted embodiment, step 422 determines if a vacuum pressure delta is greater than 30% and/or if the water pressure delta is greater than 25%. If such conditions exist, thereby indicating that the change is device usage is significant, the process advances to step 424 and the counter is reset to zero and control loops back to decision step 418. In this manner, the counter or loop is reset and the engine function continues as normal and the method continues to monitor for a state of inactivity or reduced usage. If decision step 422 indicates that a change in water pressure and/or vacuum is not significant enough to merit continued engine functioning to support washing operations, decision step 426 then determines if the counter has reached a limit, which in one embodiment is approximately twenty seconds. The count frequency, and thus, the elapsed time in seconds, can be varied to be greater than or less than twenty seconds based upon operating conditions desired. If a condition is not met within the predetermined time, control loops back to decision step 418 and normal or working engine functioning is maintained.

(21) As shown and described, a process of monitoring of pressure washing functions comprises decision steps 418 and 422. As long as water pressure and/or vacuum pressure remain substantially unchanged in step 418, a counter will continue to increment (step 420). If the counter reaches a certain predetermined value without the system having registered an appropriate change in water pressure or vacuum pressure, a control unit may automatically adjust engine function. If water pressure and/or vacuum pressure changes fail to remain below a certain threshold (“no” in step 418), the system then monitors whether or not the changes in such criteria are greater than predetermined values. If the changes are greater than the predetermined values (“yes” in step 422), thus indicating that the device is in use, the counter is reset at step 424 and the loop continues. If the changes are not greater than the predetermined values (“no” at step 422), thus indicating that the device is generally not in use, and the counter has reached a limit (“yes” in step 426), the system recognizes that changes indicative of use have not occurred within a set time period and the device or system functioning is automatically adjusted or idled-down.

(22) If step 426 determines that the condition has been met, the process advances to step 428 wherein the contact to the relay opens and the power washer idles down. The depicted process then advances to decision step 430, wherein the device may be completely powered down or the auto-idle control may be overridden. If the device is powered-down, the process reaches a conclusion. If an over-ride is selected, control loops back to decision step 410 of FIG. 4A.

(23) Although FIGS. 4A-4B and the foregoing describe one embodiment of the present disclosure wherein power washer engine parameters are monitored and appropriate responses are produced by the device and the control unit, it will be expressly recognized that the present disclosure is not limited to the operation of the described sequences and parameters. As discussed, the presently disclosed systems contemplate monitoring various parameters and providing appropriate response(s). For example, in one embodiment, a temperature sensor (e.g. thermocouple) monitors the temperature of the unit at one or more locations and based on temperature readings and certain predetermined parameters, engine functions (e.g. RPM, cooling fans, etc.) are adjusted accordingly.

(24) Although various system embodiments are contemplated as providing vacuum, water, and temperature sensors, it will be recognized that the present invention is not limited to such devices. Indeed, various other means for sensing various other parameters may be utilized in described embodiments, either in combination with or in lieu of the sensors described herein.