Pressure Washer

A pressure washer device or system that includes various control protocols associated providing an engine powered pressure washer that is convenient to operate and configured for multiple desired uses. The control protocols are preferably configured to maintain the operational integrity of the engine and pump of the pressure washer if undesirable operating conditions, such as a low oil level condition or low water flow conditions, occur during use of the pressure washer.

DETAILED DESCRIPTION

FIGS. 1 and 2show a portable engine powered power or pressure washer system or device40according to the present invention. Pressure washer40includes an internal combustion engine42that is operationally connected to a pump44. It is appreciated that one or more of the aspects disclosed herein may be applicable to power washer systems having other power sources, such as motor driven pumps, whereas other features or aspects of the proposed system are applicable only to engine powered power pressure washers, such as those features that are associated with manipulating operation of an ignition or fuel delivery systems associated with operation of the internal combustion engine. Those skilled in the art will readily appreciate the alternative uses of the various aspects disclosed herein as being usable with only one or both of engine and motor driven or powered pressure washer devices.

Engine42, or an alternate power source such as an electric motor, can be directly or indirectly (via a power transmission system such as a belt or other flexible drive member) coupled to pump44. When engine42directly cooperates with pump44without supplemental power transmission systems, pump44can be considered a direct drive pump. In such direct drive engine/pump configurations it should be appreciated that the pressure output of the pump is provided at least in part as a function of the operational revolutions per minute (RPM) of the pump and which is directly correlated to the operation speed or revolutions per minute (RPM) of the engine crankshaft. Regardless of the modality of the power source, the higher the RPM of the pump, the higher the pump output pressure—assuming other system variables to be constant. In one embodiment, the input RPM of the pump is controlled by the engine RPM by means of controlling the engine throttle such that, variable pressures can be provided at the pump output pressure via manipulation of the engine throttle or engine speed. The variable pressure output of the pump, in conjunction with a selector dial that manipulates the operating speed of the engine, allows one pressure washer to act as though it were capable of providing several different fixed operating pressures.

Pressure washer40includes a wand46that is connected to an output side of pump44via a hose (not shown). A trigger50is located at one end of wand46and a discharge nozzle52is disposed at the opposite end of the wand46. Nozzle52may be adjustable and/or replaceable to provide a desired spray pattern during operation of pressure washer40. Pressure washer40preferably includes a chassis54having one or more wheels56or other means for improving the mobility of the unit to facilitate convenient transportation of pressure washer40. Pressure washer40includes a panel, bezel, or dashboard60that includes an input control62and one or more instructional indicia64associated with the desired operation or intended use of pressure washer40. Preferably, dashboard60includes one or more indicia64that are associated with the desired operation of pressure washer40and can include one or more indicators70associated with a providing an indication as to the desired or satisfactory operation of pressure washer40as described further below.

Preferably, dashboard60also includes one or more receptacles or mounting portions61associated with supporting replaceable or interchangeable tips or nozzles72,74,76associated with the intended or desired use of pressure washer40for a particular tasks. As is readily understood, nozzles72-76are configured to interchangeably cooperate with the discharge end of wand46so as to replace nozzle52. Alternatively, it is appreciated that nozzle52can be adjustable to provide more than one spray pattern—such as a fan pattern, a consolidated stream pattern, a cone pattern, etc. It is further appreciated that wand46may have integrated nozzles that are interchangeable and/or adjustable to allow various different functions including soaping via introduction of a detergent or other cleaning or treatment agent through a venturi or other such agent injection or suction system.

Referring toFIG. 3, control62associated with dashboard60includes a dial78that is rotational and/or axially translatable relative to dashboard60to manipulate the throttle of the engine and so as to provide a desired output associated with operation of pressure washer40. As explained above, for direct drive pump configurations, the pressure output from the pump is a function of the revolutions per minute associated with pump operation and which is related to the operating speed and torque of engine42. As explained further below with respect toFIGS. 18-28, a throttle linkage extends between dial78and engine42to manipulate the operational speed of engine42and thereby the pressure generated by pump44. As explained further below with respect toFIGS. 18-28, it is appreciated that a number of methodologies are envisioned for providing the desired operational and functional connection between control62and engine42to achieve the objective of providing a user input control that is associated with manipulating an operating speed of the underlying engine42and provides a plurality of indicia associated with the desired activity or pressure output associated with operation of the engine42and effectively pump44at each respective speed associated with operation of engine42.

As shown inFIG. 3, dial78is configured to control operation of engine42to provide a desired pressure associated with operation of pump44. Dashboard60and/or dial78include one or more indicia and/or an inclined ramp or power bar indication that provide a visual indication as to the operational pressure that will be provided to wand46based on the discrete rotational position of dial78relative to dashboard60. As explained further below, the throttle associated with operation of engine42is connected to dial78via mechanical means, such as a cable or the like, and which moves rotationally and/or laterally to control the RPM of the engine and thereby the pump output pressure associated with operation of pump44.

In a preferred embodiment, the rotary throttle control associated with manipulation of dial78provides distinct throttle positions that are defined by tactile and/or audible indicia and which thereby provide a number of preset throttle positions. Preferably a plurality of such preset throttle conditions are provided by control62. In a preferred embodiment, the preset throttle positions are provided by a ball and detent association that provides a tactile indication of the throttle control position as well as retains control62at the desired orientation to provide the desired operation of engine42. The same functionality can be attained with an inclined ramp interaction with or without pronounced detents or tactile indicators. Alternatively, it is appreciated that dial78could cooperate with an underlying housing so as to provide translation of dial78in the longitudinal direction along the rotational axis associated with movement of dial78to provide the desired manipulation and/or adjustment of the throttle cable associated therewith as is discussed further below.

FIGS. 4 and 5show graphical representations of the discharge pressures that can be achieved as a function of engine speed when wand46is provided with alternate nozzle configurations. As shown inFIG. 4, when pressure washer40is equipped with a first nozzle, a generally linear plot can be achieved when comparing the operating discharge pressure relative to a fully loaded engine operating speed. Changing the replaceable nozzle to have a different shape or sized orifice provides a different operating pressure range when the pump is driven at alternate full load engine speeds. Said in another way, pressure washer40provides different operating pressure spray conditions as the engine operating speed is manipulated for each of different nozzle shapes and/or sizes and the range of operating pressures alters as a function of the characteristics of the different nozzles. It should be appreciated that connecting any of nozzles72,74,76to wand46will alter the pressure to engine speed curve but each curve provides alternate working pressure flows across a range of achievable operating pressures for each respective nozzle. It is further appreciated that control62may be provided with different indicia as described further below with respect to associating the setting of control62, associated with a discrete speed of operation of engine42, with a respective nozzle which is connected to wand46.

FIG. 6shows an underside and a detailed view of control62associated with dashboard60. As shown inFIG. 6, control62includes a step plate80that is secured to an underside82of dashboard60by one or more bosses84. Step plate80defines an axis of rotation86of dial78relative to step plate80and dashboard60. Said in another way, dial78is rotatable relative to dashboard60and step plate80so as to manipulate the speed of operation of engine42and thereby the operating pressure generated by pump44.

Referring toFIGS. 6 and 7, control60includes a rotor88that rotationally cooperates with a synchronizer90and is disposed between synchronizer90and step plate80. Rotor88includes a recess94that is configured to cooperate with an end of a throttle cable associated with operation of engine42as is described further below with respect toFIGS. 18-29. An underside96of rotor88includes one or more bosses98that translate rotationally relative to a ramp surface100of step plate80. Preferably, ramp surface100include one or more steps or lands102,104,106configured to provide a tactile indication as to the rotational position of rotor88relative to step plate80. Cooperation of bosses98along ramp surfaces100allows rotor88to translate in the longitudinal direction associated with the axis of rotation of dial78, indicated by arrow110, relative to step plate80and thereby manipulate the operational length associated with a throttle cable or an instantaneous setting of the engine throttle assembly.

It should be appreciated that clockwise rotation of dial78translates rotor88, and thereby throttle cable recess94, in a longitudinal direction along axis110effectively “pulling” the throttle cable whereas counter-clockwise rotation of dial78allows the throttle assembly to “push” the throttle cable. The “push” and “pull” manipulation of the throttle cable manipulates the throttle assembly associated with engine42to reduce and increase the operating speed of engine42. It is further appreciated that the “push” of the throttle cable could be provided as merely allowing the throttle assembly to return to a biased orientation as compared to actually “pushing” the cable to achieve the desired orientation of the throttle and thereby the desired operation of the engine.

It is further appreciated that the rotational association of dial78relative to the manipulation of the underlying throttle assembly could be reversed such that counterclockwise rotation of dial78increases the engine speed whereas clockwise rotation of dial78decreases the operating speed of engine42. Preferably, regardless of the direction of rotation of dial78relative to increasing and/or decreasing the operating speed of engine42, the throttle assembly is biased toward a position associated with idle operation of engine42such that user interaction with dial78increases the throttle positioning and thereby the operating speed of engine12. More preferably, once increased, it is appreciated that control62maintains the desired engine operating speed associated with the particular throttle position associated with the setting of dial78relative to control62until subsequent user interaction with dial78and/or automatic interference with operation of engine42as disclosed further below.

Still referring toFIGS. 6 and 7, synchronizer90includes a first tang112and a second tang114that preferably have dissimilar sizes. Rotor88includes a first cavity116and a second cavity118that are each configured to cooperate with only one of the respective tangs112,114of synchronizer90. Such a construction ensures a repeatable and a singular rotational orientation associated with assembling synchronizer90relative to rotor88so as to provide a desired orientation of synchronizer90and dial78relative to dashboard60and the throttle cable assembly associated therewith.

Referring toFIG. 8, an underside120of dial78includes a cavity122that is constructed to secure dial78to synchronizer90. Cavity122includes one or more ribs124that cooperate with the detent126formed in synchronizer90to define the orientation of dial78relative thereto. Synchronizer90cooperates with an underside of dashboard60whereas dial78is exposed proximate a front side of the dashboard and correspondingly oriented relative to the indicia provided on the front side of dashboard60so as to be indicative of the desired cleaning operation and/or pressure intended to be provided by pressure washer40and to exposed to the user for setting the engine throttle speed associated with generating the flow pressure for performing the intended operation. The single orientation structural interaction between dial78, rotor88, and synchronizer90ensures that the indicia68associated with the orientation of dial78relative to dashboard60provides the desired indication or association between the orientation of the dial78relative to the throttle assembly to achieve the desired operational condition of engine42and thereby the generation of the desired operating pressure associate with driven operation of pump44.

FIG. 9shows a detailed view of the dashboard area16of pressure washer40. As shown inFIG. 9, pressure washer40can be configured to include an “on/off” switch131, one or more indicators132, one or more engine controls134, such as an engine choke control, etc. Preferably, those controls of pressure washer40that are commonly interacted with by a user are all generally centrally positioned on dashboard60proximate dial78. It is further appreciated that dial78could be configured to include the functionality of “on/off” switch131and/or choke control134as explained further below. It is further understood that although indicators132are shown as being positioned proximate dial78on dashboard60, other locations are envisioned including being supported by dial78. The centralized location of all of the operational controls associated with the starting and operating of pressure washer40provides a pressure washer wherein a user need only inspect a limited area of the device to quickly assess the overall operating condition of the device.

One or more nozzles72,74,76are positioned proximate dial78so as to be readily identifiable and accessible to the user of pressure washer40. It is appreciated that the operation and manipulation of dial78can be configured to provide a number of indicia that assimilate the operating condition of the engine and/or the desired pressure intended to be provided via operation of pressure washer40and/or assimilate the position of dial78relative to the operation condition of engine42as well as a respective nozzle72,74,76engaged with wand46. Referring toFIGS. 10-12, indicia68can be provided as one or more of the desired output associated with operation of pump44, such as a pressure reading or range as shown inFIG. 10, as an activity to be undertaken such as shown inFIG. 11, or a combination thereof as shown inFIG. 12. That is, dashboard60and/or dial78might have an icon indicating a fence, a vehicle, walls, windows, driveways, or other structures or graphical indicia associated with the activity that is to be undertaken. Rotating dial78to the desired indicia68would set the corresponding water discharge pressure associated with operation of pump44to the preferred, desired, or optimal value for undertaking the desired activity by manipulation of the engine throttle control as explained above.

It is further appreciated that indicia68may be provided in multiple radially oriented rows or sequences such that a first row of indicia68may provide an indication associated of desired pressure output, a second row may include indicia indicative of the activity to be undertaken, range of engine speed operation or throttle control position, etc. It is further appreciated that such rows may include a legend or key associated with assimilating the desired pressure flow signal, engine speed condition, or activity to be completed with a respective nozzle that is connected to wand46as disclosed above. It is further appreciated that pressure washer40may be provided with multiple placards that each include multiple indicia and which the end user can position relative to dial78; one of which the discrete user or end purchaser considers the most convenient or readily understandable for assessing and setting the desired operation of pressure washer40. That is, it is appreciated that whereas some users may appreciated a power bar type of indicia associated with the various positions of dial78, other users may prefer graphical indicia associated with respective activities that are to be undertaken.

It should be further appreciated that control62can be provided as various other operational modalities other than being provided as a rotational dial. It is appreciated that the functionality of control62could be provided in other modalities such as a slide lever, a push/pull lever, a pushbutton, or the like. It is further appreciated that control62can be configured to provide one or more mechanical, tactile, visual, or audible, indications associated with indicating the setting of control62for the desired operation of pressure washer40. Regardless of the mode of operation of control62, the inclusion of operational indicators132proximate dashboard60provides a power washer40wherein most if not all of the operational controls associated with operation and/or monitoring of pressure washer40are conveniently located in a common area.

As shown inFIG. 13, pressure washer40is intended to include both conditional operational indicators132, such as oil and water condition indicators, and consumable level indicators134in the general proximity of dashboard60. Such a configuration allows the user to quickly assess the operating condition of pressure washer40without undue examination or inspection of different areas of the pressure washer40to assess the condition of the discrete systems associated therewith.

Referring toFIG. 14, pressure washer40includes a controller or control circuit140that is configured to assess various operational and system integrity or operational control signals. Preferably, control circuit140is configured to suspend operation of engine42if a low oil condition is detected and preferably persists beyond a desired interval. Control circuit140also preferably monitors pump inlet pressure and/or pump temperature and is configured to suspend operation of pressure washer40, or minimally provide illumination of one or more of indicators132,134during low engine oil, low intake water pressure conditions, and/or pump overheat conditions. In a preferred embodiment, pressure washer40includes a hall-effect sensor141(FIG. 2) or other fluid/oil level sensing device that is connected to engine42and controller140. Controller140can be configured to simply provide an indication of receipt of the signal from the oil condition sensor141and/or suspend operation of engine42if a low oil condition exists or persists for a selected duration during operation of engine42.

In addition to the oil condition monitoring, it is appreciated that pressure washer40include one or more sensors145(FIG. 13) associated with detecting various parameters associated monitoring operation of the pump flow conditions.FIG. 30shows one such configuration wherein pump44is can be configured to include one or more temperature sensors139such as thermocouples to assess the operating temperature of pump44. Preferably, the one or more thermal couples139are connected to controller140so that operation of pressure washer40can be suspended in the event of an over-temperature condition. Alternatively, it is envisioned that sensors139be provided as pressure sensors145(FIG. 14) associated with assessing a pressure signal associated with the inlet pressure of the working fluid or an output pressure of the working fluid. Controller140can be configured to provide an indication of an unsuitable working fluid flow parameter and/or manipulate operation of engine42or pump44in response to detection of such a situation.

In a preferred embodiment, all such indicators and/or manipulation of the desired operation of pressure washer40are limited by a debounce algorithm that mitigates false positives of the any of the low oil, low pump intake pressure, high pump operating temperature, the latter of which can be caused by kinked feed hoses or the like. Such a debounce operation allows the operator a suitable period to clear the unintended but undesired operational condition without unduly interfering with operation of pressure washer40.

In a preferred configuration, the electronic circuit associated with controller140is provided on pressure washer40to provide a visual indication of the low pressure of the inlet water. Preferably, the circuit also provides an indication of low engine oil condition as disclosed above via indicators132,134positionally associated with dashboard60. Such a configuration protects the integrity of the pressure washer from damage due to extended periods of operation at low input water pressure, thereby protecting the operational integrity of pump44, and low engine oil conditions, thereby protecting the operation integrity of engine42. In a preferred aspect, rather than simply interrupting or interfering with operation of washer40, controller140is configured to provide user feedback to indicate when the respective switches become active. Such an indication can be provided as a sequential actuation of the one of more of indicators132,134. Preferably, dashboard60includes textual or graphical explanations related to the operation or illumination of indicators and the causes associated with actuation of the same. Such feedback allows the user to quickly and accurately troubleshoot the cause of unintended device shutdowns, such as no fuel, low oil, engine failure, pump stalling, pump temperature, pump flow, etc. The feedback directs the user to the cause of the shutdown so that shutdown conditions can be expeditiously rectified.

As mentioned above, controller140also includes an algorithm that is provided in conjunction with the pressure shutdown to prevent false shut downs and provide an adequate annunciation period to allow the user to recognize the source of the problem and correct it while still getting feedback. In a preferred embodiment, the sensor error signals are provided as one or more LED's such as indicators132,134that illuminate at an error condition and/or a continual indication of the present state of engine oil and/or pump water.

In a preferred embodiment, referring toFIGS. 14 and 17, the control circuit associated with controller140includes a magneto positive and negative detection section150, a magneto shutdown section152, a water pressure switch monitor section154, an indicator section156, and a low power microcontroller section158that is preferably powered by a lithium type battery. In use, controller140has various modes of operation further characterized as:

Sleep Mode

When the microcontroller detects that there are no magneto pulses, it goes into sleep mode. In this mode, the total circuit draw is less than 11 microamperes preferably as a worst case calculation. The battery is preferably rated for 225 milliamp hours of operation and, with the above current draw; the shelf life of the battery in sleep mode would be approximately 2.7 years. The measured current draw with the indicator in sleep mode was less than 0.3 microamperes which equates to a greater than 50 year shelf life associated with operation of controller140.

Wake Up

When the microcontroller detects a positive magneto pulse, it wakes up and briefly flashes the LED associated with one or more of indicators132,134. This flash notifies the user both that the circuit is awake and that the one or more LED's or indicators132,134are functional.

Oil Switch Failure Detect

During normal operation of pressure washer40, in a preferred embodiment, the respective oil level indicator receives positive and negative pulses from the magneto. When there is an oil level failure or low oil level condition, the oil level shutdown circuit shorts, shunts, or grounds the negative magneto pulses. During shorting of the negative magneto pulses, the ignition or combustion signal is not communicated to the sparkplug associated with operation of engine42such that operation of pressure washer40automatically terminates. If the indicator detects the loss or shorting of the negative magneto pulses, the low oil indicator flashes an oil fail pattern on the LED, for example a pattern of ON or illuminated for 1 second, OFF for 1 second, repeat; or a pattern of a dash illumination signal, followed by OFF, and repeat. Understandably, dashboard60can be provided with more than one failure indicator such that an illuminated indicator is indicative of either a particular system OK condition or a particular system failure or warning condition. Regardless if provided as a single or a multiple system failure or warning indicator, the LED can continue to flash for 1 minute after shutdown before the circuit will go to sleep. In a preferred embodiment, reactivation of the system will repeat the oil failure alert until the low engine oil condition is cleared or rectified such as by replenishing the engine oil to a suitable or operational level.

Water Switch Failure Detect

During normal operation of pressure washer40at any of the operational conditions associated with the relative position of dial78, controller140is also preferably configured to assess one or more conditions associated with the status of the working fluid. While pressure washer40is operating normally, controller140or an associated microcontroller sends a 3V signal to a water pressure switch145(FIG. 14). When the input water pressure is sufficient to achieve the expected or desired operation of pressure washer40, the pressure switch remains open and the microcontroller detects the 3V signal via monitoring of the signal. When the water pressure is insufficient to support desired operation of pressure washer40, this pressure signal deviates in a downward direction or is pulled down from the suitable operational signal. Controller140preferably starts a counter associated with generating a delay when the low signal or deviation of the 3V signal is detected.

If the counter reaches a threshold, such as 4 seconds of low signal, the magneto engine shutdown circuit engages and the indicator flashes a water pressure failure pattern on one or more of the respective LED's associated with indicators132,134. Such an indication pattern can include illumination of the low flow pressure indicator in a suitable pattern such as ON for a ½ second duration, OFF for a ½ second duration, ON for ½ second duration, OFF for a 1 second duration, repeat. Such operation can be referred to a dot, dot, OFF, pattern. The LED can continue to flash the pattern for a selected duration, such as for approximately 1 minute, after shutdown before controller140returns to the sleep operation described above. Although pressure washer40is disclosed as including multiple indicators132,134, it is appreciated that a single indicator could be provided which operates in selected patterns associated with indicating to the user the basis for a particular shut-down operation.

Turn Off

When use of pressure washer40is complete and the user desires to suspend operation of the pressure washer, dial78or a supplemental ON/OFF switch can be moved to an OFF position that is associated with terminating, grounding, shunting, or shorting both the positive and negative pulses associated with the magneto. Controller140processes the no magneto pulses as a safe for operation condition such that no engine or pump operation failure signals are generated or indicated. If there are no failure conditions when pressure washer40is shut down, controller140returns to the sleep mode after a selected duration such as 4 seconds and pressure washer40returns to a condition suitable for subsequent operation of the pressure washer40.

Restart: Oil Level Failure

During a restart activity after a low oil condition engine shut down, controller140is configured to assess and confirm that the low oil level condition has been rectified prior to allowing engine42to start. In a preferred embodiment, if the oil level sensor recovers to a safe operation condition while the associated indicator is still flashing, engine42can be restarted. The respective oil condition indicator will continue to provide an oil level indicia until power washer40restarts or a selected duration, such as 1 minute, elapses. If the oil level sensor does not provide a safe to operate indication, the indicator will continue to alarm, via an indication such as illumination of one or more of indicator132,134, as the user cranks or otherwise attempts to start engine42until the low oil condition is rectified.

Restart: Water Pressure Failure

After a water pressure failure shut down of operation of engine42, if the water pressure is restored, controller140will allow the respective flow pressure indicator to recover to a safe operation indication, such as turning off the indicator, and allow the indicator to stop blinking after a selected duration such as a few seconds. Upon recovery of a suitable operation water pressure, assuming a safe oil level condition exists; engine42of pressure washer40is allowed to restart via termination of the grounding or shunting of the engine ignition signal.

The various operational control sequences disclosed above allow pressure washer40to be protected from the detrimental effects associated with extended periods of operation with any or all of low water flow pressure, high pump operating temperatures, and/or low engine oil conditions. It is appreciated that the various operational parameters and time intervals discussed above are merely exemplary of one preferred operational configuration of pressure washer40. It is appreciated that the various values and/or intervals may be manipulated to satisfy other user and/or application demands.

Regardless of the specific operational parameters, pressure washer40provides a pressure washer whose operation can control the pressure output of the pump by manipulation of the engine operating speed or engine throttle and preferably can be utilized to modify pump discharge pressure as a function of engine operating speed. The control associated with such operation includes a control that is assimilated with a task or activity selector and provides the ability to select task or activity specific pressure selection with optional task or activity iconography. The control system provides consolidated controls to enable ease of use for the end customer and preferably provides feedback of the control position with detent, tactile, audible, and/or a pointing arrow. Alternatively, it is appreciated that the position of dial78, which is associated with an engine operating speed, could be used to point to pressure settings in pounds per inch squared (psi) instead of icons. Dial78and/or dashboard60could also incorporate other “one touch interface” functions such as the ON/OFF position, choke position, start position, etc. It is further appreciated that dial78could also be used to engage an electric start feature that would start engine42based on a rotational or axial position of the dial78were power washer40equipped with the systems associated with effectuating the same, such as a battery and an electronic starter and the electrical connections associated with suitable operation of the same.

In a preferred embodiment, pressure washer40also provides one or more visual indications of low water pressure conditions in the pressure washer in conjunction with pressure sensing ability via a pressure switch or similar device. Use of visual indications of low oil in the pressure washer with low oil sensing ability in the engine—via a sensor such as a Hall Effect type sensor or similar device, allows power washer40to protect the operational integrity of engine42as well as pump44while providing the user with an indication as to the cause of suspension or prevention of operation of engine42. Preferably, controller140includes a debounce algorithm that provides one or more delays as disclosed above when responding to instantaneous signals associated the oil level and/or fluid flow pressure switches to prevent false alarms from causing nuisance shut downs of pressure washer40. The duration of the debounce period is preferably chosen to allow pressure washer40to maintain operation during normal operating events such as air pockets in the operating fluid water stream and/or temporary kinks associated with a water delivery hose without suspending operation of the device due to such transient deviations that can occur during normal operation of pressure washer40.

FIGS. 15 and 16show various operating pressures that can be achieved and delivered to wand46associated with operation of engine42at various operating speeds as function of the relative manipulation of the engine throttle cable via user interaction with dial78. As shown inFIG. 15, in a preferred embodiment, dial78achieves and maintains various discrete positions that are associated with different engine operating speeds and which are associated with providing different operating pressures associated with various output nozzles. In a preferred embodiment, rotation of dial78between the respective discrete radial positions associated with steps100,102,104(FIG. 7) provides incremental adjustment of the throttle position associated with operation of engine42. As explained further below, it is appreciated that other numbers of preset throttle positions can be provided by control60.

The trend lines shown inFIGS. 15 and 16are indicative of one such control wherein the control is movable to allow adjustment of the operating length of the throttle cable in 0.5 mm increments and through a range of motion of zero extension of the cable to 5.5 mm of total extension of the cable. Understandably, such dimensions are merely exemplary of one control and throttle association of the present invention.FIGS. 15 and 16show that various operating flow pressures can be achieved via manipulation of the engine throttle speed with control60during both loaded and unloaded conditions associated with the operation of the underlying engine42. Understandably, the number of preset engine throttle conditions and total travel of the throttle cable can be manipulated to satisfy parameters associated with different engine and/or throttle constructions as well other parameters associated with the operation of pressure washer40, such as the range of pressures that can be generated from operation of a particular pump and/or provided via use of alternate nozzles. Regardless of the number of preset throttle positions associated with each discrete position of dial78of control60, control60is preferably configured to manipulate the pressure flow from a lowermost usable pressure to a maximum pressure that can be provided with a given pump and engine association.

FIGS. 18-21show a throttle assembly144associated with a throttle body160and one or more cables164, or such as throttle and choke cables166,222, associated with communicating the throttle instructions from control60to throttle assembly144of engine42. As is commonly understood, manipulation of the throttle and choke cables manipulates the combustion charge and the air associated therewith that is delivered to a combustion chamber of engine42to effectuate starting and sustained operation of engine42at various engine speeds associated with the position of a throttle plate relative to a passage through the throttle body160.FIGS. 18-19and27-29show two alternate preferred embodiments for providing the mechanical throttle connection between the user adjustable control60and a throttle body160and/or an engine governor system associated with operation of engine42. Regardless of the construction of the control or the throttle assembly, the adjustable throttle control associated with generating a desired flow pressure output also provides the user the ability to better manage sound output associated with operation of the pressure washer40. That is, when less than peak operating pressures are desired, engine42of pressure washer40can operate at a less than maximum engine RPM to generate the desired pressure signal output thereby reducing the decibel level associated with operation of engine42and making pressure washer40more affable to consumers.

Referring toFIGS. 18-21, as mentioned above, throttle body160of engine42is configured to deliver a fuel charge to the combustion chamber associated with operation of the engine42. The throttle body160includes a choke lever162that effectuates the choking of engine42during starting processes. A choke cable164extends between choke lever162and a choke pull associated with dashboard60or control62as described above and further below with respect toFIG. 21. Throttle cable166is connected to a throttle linkage168and manipulates the orientation of the throttle plate associated with throttle body160. An alternate end of throttle cable166is connected to control60such that operation of dial78manipulates throttle linkage160associated with throttle body160. Said another way, manipulation of dial78manipulates the operating speed of engine42during operation of engine42.

As shown inFIG. 19, throttle linkage168includes one or more springs170,172that are configured to bias throttle linkage168toward an idle position. As alluded to above, such a configuration allows engine42to return toward lower engine operating speeds during rotation of dial78in a respective clockwise or counterclockwise direction.FIGS. 20 and 21show throttle cable166and choke cable178removed from power washer40. As shown inFIG. 20, throttle cable166includes a sheath180and a cable182slidably contained therein. A first end184of cable182includes a stopper or ball186that is shaped to be received within the recess94of rotor88as shown inFIG. 7. Translation of ball186from a terminal end188of sheath180yields translation, indicated by arrow190, of a second end192of cable182thereby effectuating manipulation of throttle linkage168so as to alter the operating speed of engine42.

In a similar manner, referring toFIG. 21, choke cable178includes a sheath196disposed about a cable198. A pull200is secured to first end of choke cable198and is preferably mounted on dashboard60. A second end202of cable198is configured to cooperate with choke lever162such that manipulation of pull200effectuates translation of choke lever162relative to throttle body160, as shown inFIG. 18, thereby choking engine42. Understandably, manipulation or operation of choke cable178is generally only necessary during starting or cold starting operations of engine42whereas manipulation of throttle cable166effectuates changes in the operational speed of engine42at any time during operation of the engine. As such, operation on dial78effectuates manipulation of throttle cable182, and thereby throttle linkage168, and alters the operating speed of engine42to create changes in the output pressure associated with operation of pump44.

FIGS. 22-26show various views of a control218having a dial220associated with a throttle cable222according to another embodiment of the invention. Preferably, control218and dial220are constructed to cooperate with dashboard60of pressure washer40to effectuate similar engine throttle control as disclosed above with respect to control60and dial78. Dial220is secured to a mount or dial mount224that is constructed to be secured proximate dashboard60. Alternatively, it is envisioned that dial mount224could be formed integrally with dashboard60.

A gear or a pinion226extends from a rearward facing side of dial220and operationally cooperates with a toothed interface or a rack228that is slidably oriented relative to dial mount224. A support230extends from dial mount224and slidably cooperates with a groove232formed in rack228to maintain a desired alignment between rack228and pinion226associated with the interaction between dial220and throttle cable222. Throttle cable222is secured to rack228such that rotation of dial220results in longitudinal translation, indicated by arrow234, of cable222relative to a cable mount236secured to dial mount224. It is appreciated that rack228could be constructed to cooperate with the ball shaped end184of throttle cable166. Like control60, longitudinal translation of cable222effectuates changes in the engine operating speed in the same manner as discussed above. That is, it should be appreciated that the alternate end of throttle cable222is connected to the throttle linkage associated with the throttle body of an underlying engine42as disclosed above.

Dial mount224also includes a number of cavities250that cooperate with a ball252(FIG. 26) that is biased towards the cavities250by a spring254. Ball252and spring254are supported by dial220such that rotation of dial220effectuates translation of ball252relative to the respective cavities or detents250. The cooperation of the ball with the discrete detents provides a tactile indication as to the relative position or discrete changes in the position of dial220relative to dial mount224and thereby the position of throttle cable222relative to the throttle assembly connected to an alternate end of the throttle cable and associated with the underlying engine42. It is appreciated that dial220can be configured to cooperate with a dashboard60having operational indicia like those disclosed above so as to provide a graphical indication as to the operational condition of the pressure washer so equipped. It is further envisioned that dial220and throttle cable222can be provided on pressure washers having the pump intake pressure, pump temperature, and engine oil temperature safety protocols discussed above as well as other engine driven devices wherein a robust user input to throttle linkage communication is desired.

FIGS. 27-29show various views of a throttle assembly260associated with engine42and connected to a throttle cable such as one of throttle cables166,222. It should be appreciated that the opposite end of throttle cable166,222can be operationally connected to either of control60or control218to effectuate communication of the user throttle input signal to a throttle assembly260associated with an engine42of pressure washer40. Throttle assembly260includes a throttle level268and a choke lever270that are positionally associated with one another so that actuation of throttle lever268beyond a desired maximum operating throttle position associated with a maximum operating speed of engine42to manipulate actuation of choke lever270to effectuate choking of engine42. After starting of engine42, choke lever270is allowed to return to a non-actuated position such that manipulation of throttle lever268manipulates the operation speed of engine42without influence of an engine choking action. Understandably, it is further appreciated that throttle lever268and choke lever270can be provided in an independently operable configuration wherein each of the throttle lever268and choke lever270do not interact with one another in a manner wherein manipulation of one of the throttle lever268or choke lever270does not affect the orientation of the other of the throttle lever268and the choke lever270.

Throttle assembly260preferably includes one or more stops272associated with setting the relative minimum and maximum throttle positions. Preferably, stops272are adjustable to allow tuning of the relative maximum and minimum throttle positions associated with a desired maximum operating speed of engine and a relative minimum operating speed or idle operation of engine42. Cable182of throttle cable166,222engages throttle lever268and sheath180of throttle cable166,222is secured to throttle assembly260via a clamp274such that actuation or manipulation of the control60,218connected to the opposite end of a respective throttle cable166,222effectuates longitudinal translation of cable182and thereby manipulation of throttle lever268relative to throttle assembly260. The various discrete positions associated with controls60,218allows operation of engine42at various discrete speeds to achieve the desired pressure flow output associated with each of the respective indicia that are positionally associated with respect to the respective user control60,218for which pressure washer40is equipped.

FIG. 31is a view similar toFIG. 1of pressure washer40and shows movement of the handle portion300of pressure washer40between an in-use orientation302and a folded, stowed, or stored orientation304relative to pressure washer40. When oriented in the in-use orientation, handle portion300extends in a generally upward direction proximate a rear portion of pressure washer40and when oriented in the stored orientation304handle portion300is positioned in close proximity to a top surface associated with the engine42and dashboard60of pressure washer40so as to provide a comparatively compact configuration of the same.

Chassis54includes a first vertically oriented member306and a second vertically oriented member308that are connected to U-shaped handle portion300by respective joint assemblies310,312. As alluded to above, when oriented in the upward or in-use orientation302, handle portion300extends generally above engine42of pressure washer40and defines a grip site314useful in facilitating manual transport of pressure washer40. That is, user interaction with grip site314allows pressure washer40to be tipped in a generally rearward direction so as to be supported by wheels56. When not in use, handle portion300can be rotated in a generally forward direction and is shaped to snuggly cooperate with an upper portion316associated with the power unit of pressure washer40. Handle portion314is also preferably contoured to snuggly cooperate with control panel or dashboard60of pressure washer40to provide a compact orientation thereof when pressure washer40is not in use. It is appreciated however that pressure washer40can be operated with handle portion300in both the in-use orientation302and the stowed orientation304relative to the remainder of pressure washer40.

Referring toFIGS. 32 and 33, each joint assembly310,312includes a first lobe320that is secured to a respective upright member306,308associated with chassis54. Handle portion300includes laterally oriented downward extending portions322,324that each have a second lobe326of joint assemblies310,312secured thereto. Respective first and second lobe pairs320,326rotationally cooperate with one another to allow translation of handle portion300between the in-use orientation302and the stored orientation304.

A first side328of each first lobe320includes a pair of projections330,332that extend in a transverse direction relative to the generally planar orientation of lobe320or in a direction aligned with the axis of rotation associated with the respective joint assemblies310,312. Projections330,332are each shaped and positioned to be received in a respective chase334,336defined by a first side338of each second lobe326. Each second lobe326includes one or more projections340,342that are shaped to cooperate with respective pockets344,346formed in first side328of each first lobe320. Pockets344,346are oriented radially outboard relative to projections330,332or each first lobe320. Projections330,332of each first lobe320and projections340,342of each second lobe326are shaped to cooperate with a respective chase334,336or pockets334,346to facilitate an indexed and self retained orientation of handle portion300relative to the in-use orientation302and the stored orientation304thereof.

Each joint assembly310,312includes a fastener, such as the carriage bolt352, having a stem portion354and a head portion356. Stem portion354of carriage bolt352passes through an opening358formed in a respective second lobe326and an opening360formed in each respective first lobe320and operationally cooperates with a nut362associated with the respective joint assembly310,312. In a preferred embodiment, opening358associated with each second lobe326has a shape that slidably but non-rotationally cooperates with a contour364positioned proximate head portion356of each carriage bolt352. The cooperation of contour364with opening358of each second lobe326prevents rotation of carriage bolt352during manipulation of nut362.

Each nut362includes a threaded bore368that threadably cooperates with stem354of a respective carriage bolt352. In outer radial surface370of each nut362is shaped to provide toolless manual manipulation of nut362relative to a respective carriage bolt352. Nut362and carriage bolt352of each joint assembly310,312cooperate with one another to allow lateral translation, indicated by arrow374, of each respective first lobe320relative to the corresponding second lobe326of each joint assembly310,312such that each joint assembly310,312can be loosened to allow projections340,342of second lobe326to translate relative to a respective pocket344,346associated with a respective first lobe320without full disassociation of the respective joint assembly310,312such that handle portion300can be rotated between in-use orientation302and stored orientation304without disassembly of the respective joint assemblies310,312.

The association of projections330,302of perspective first lobes320with corresponding chases334,336of a corresponding second lobe326prevents over rotation of handle portion300relative to the in-use orientation302and stored orientation304when joint assemblies310,312are even loosely associated. Rotation of nut362in a tightening direction when handle portion314is oriented in either of the in-use orientation302of the stored orientation304biases each respective first lobe320into engagement with a corresponding second lobe326such that at least one of projections340,342of second lobe326are laterally associated with a corresponding pocket344,346in a manner that prevents rotational interaction between the respective first lobe320and a corresponding second lobe326. Such cooperation prevents the inadvertent rotation of handle portion300from the relative in-use orientation302and/or stored orientation304. Each joint assembly310,312provides a robust physical connection that allows extension and/or retraction or collapsing of handle portion300relative to the remainder of pressure washer40.

Accordingly, pressure washer40provides a user interface or control that is easy to understand and convenient to interact with such that the user can expeditiously configured the pressure washer for an intended operation via manipulation of an engine throttle control. The control is further configured to provide a variety of indicia indicative of the intended or desired operation of the pressure washer. Regardless of the methodology associated with the construction of the respective control and indicia, pressure washer40is also configured to assess the operating condition of the engine and/or the pump to protect the operational integrity of one or both of the engine and pump. Preferably, pressure washer40also includes one or more indicators associated with providing the user information as to the suitable operable condition of the engine and pump. More preferably, each of the indicators, indicia, and controls are provided in a common area of the pressure washer to mitigate user inspection of various areas of the pressure washer for assessing the operational condition and state of the pressure washer. As such, pressure washer40is convenient to operate, provides various usable working flow pressures that are attained by manipulation of the engine operating speed, protects the engine and pump of pressure washer40from damage due to operation of the engine and/or pump at less than suitable conditions, and provides such protection in a manner that accommodates tolerable transient operating conditions.

Many changes and modifications could be made to the invention without departing from the spirit thereof. The scope of these changes will become apparent from the appended claims.