Patent Application
20150022334
Not applicable.
Not applicable.
This disclosure relates to work vehicles, and in particular to a system for providing user feedback of the fill levels of onboard fluid reservoirs in work vehicles.
Motorized vehicles, such as work vehicles used in the construction and forestry industries, have reservoirs that hold various fluids, such as coolant, fuel, engine oil and hydraulic oil, that must be maintained and refilled on a regular basis. Conventional work vehicles are equipped with some type of mechanical or electrical device that indicates the level of fluid in the reservoir. For viscous fluids, for example, the device may be a conventional dip stick with graduated markings that can be inserted into and removed from the reservoir to take a measured sample of the fluid indicative of the level of fluid in the reservoir. The device could also be a sight gauge in the form of a window in the wall of the reservoir with or without graduated markings that gives a direct line of sight into the reservoir. The device could also be a conventional mechanical level sensing mechanism with a movable needle gauge or an electromechanical level sensor arrangement that sends an electrical signal to a dedicated electronic gauge or display interface.
All of the aforementioned devices are best suited for indicating the fluid level of a reservoir at some point after it is filled with the fluid, and are cumbersome or ineffective to use while adding fluid to the reservoir. For example, dip sticks require the filler to frequently stop adding fluid to the reservoir to take dip stick readings in order to determine whether the maximum or other appropriate fill level was been reached. This process is time consuming and can lead to over-filling the reservoir. Sight gauges can be difficult to view while filling as well since, particularly in heavy-duty work vehicles, they are ordinarily hidden beneath vehicle body panels or dedicated guards in order to protect the gauge from hazards of the operating environment. And if not hidden, sight gauges are susceptible to being damaged, which could also inhibit the operation of the vehicle if the reservoir is compromised. Lastly, mechanical or electromechanical devices that are read at gauges in the instrument cluster or display interface in the vehicle cabin either require the filler to stop filling to check readings in the cabin or require an additional person to assist in filling the reservoir.
An additional problem with some fluid reservoirs in work vehicles is determining the correct fill level when the desired fill level is less than the maximum capacity of the reservoir such that both automatic shut-off systems and visual inspection of the filling orifice are not effective. Further, in some cases the desired fill level varies depending on certain operating conditions. For example, the desired fill level of a hydraulic oil tank varies depending on whether the fluid is hot or cold because the thermal expansion of the oil that occurs during operation requires an air space to be left in the reservoir to accommodate for the additional volume occupied by the fluid at elevated temperatures. As a result, the reservoir can be effectively over filled when the system is at elevated temperatures or under filled at lower temperatures, even if the fluid is filled to a constant height within the reservoir.
This disclosure addresses the aforementioned problems.
This disclosure provides a system to assist a vehicle operator, mechanic or other worker in adding the proper amount of fluid to a fluid reservoir onboard a work vehicle. The system provides a user feedback alert or alarm that progresses in intensity as the fluid level rises within the reservoir during the filling process. The alert can be visual, audible or tactile, and can use system-dedicated controls, interfaces and feedback devices or be incorporated in already existing components of the work vehicle.
As one example, when someone fills an onboard fluid reservoir, an audible alert, such as a horn of the work vehicle, can sound with increased frequency and amplification as the fluid level approaches the desired fill level. Alternatively or additionally, a visual alert, such as activation of the work vehicle work light or headlights, can illuminate with increased frequency and luminescence as the fluid level approaches the desired fill level. The progressive feedback alert system disclosed herein is a particularly effective aid in filling reservoirs with sub-maximal or varied desired fill levels, such as a hydraulic oil tank.
The progressive alert system can include as main components a fill level sensor, an electronic control unit and a feedback device. The fill level sensor is coupled to the control unit which provides a progressive feedback signal to the feedback device to generate a user alert that is proportional to the fluid level in the reservoir. A fluid temperature sensor can also be coupled to the control unit to take into account different temperature-dependent fill levels when generating the alert feedback. A user interface display can also be coupled to the control unit to output sensor information and allow for user selection of system settings.
Thus, in one aspect, this disclosure provides a system for providing a progressive feedback alert of reaching a pre-determined fluid level in a fluid reservoir during filling of the reservoir, in which the system includes: a fill level sensor coupled to the reservoir to detect the rising fluid level within the reservoir during filling of the fluid in the reservoir, the fill level sensor configured to output real time fill level signals based on the changing instantaneous level of fluid in the reservoir; a control unit communicatively coupled to the fill level sensor to receive the fill level signals and configured to execute control software to analyze the fill level signals received from the fill level sensor and output feedback signals that are proportionate to the instantaneously levels of fluid in the reservoir; and a feedback device communicatively coupled to the control unit to effect an alert based on the feedback signals received from the control unit, wherein one or more parameters of the alert progressively changes as the reservoir fluid level rises.
In another aspect, this disclosure provides a system for providing a progressive feedback alert of reaching a pre-determined fluid level in a fluid reservoir during filling of the reservoir, in which the system includes: a fill level sensor coupled to the reservoir to detect the rising fluid level within the reservoir during filling of the fluid in the reservoir, the fill level sensor configured to output real time fill level signals based on the changing instantaneous level of fluid in the reservoir; a fluid temperature sensor coupled to the reservoir and configured to output a temperature signal to the control unit based on a temperature of the fluid in the reservoir; and a control unit communicatively coupled to the fill level sensor to receive the fill level signals and to the temperature sensor to receive the fluid temperature signal, wherein the control unit is configured to execute control software to analyze the temperature signal from the temperature sensor and the fill level signals from the fill level sensor and output feedback signals that are proportionate to the instantaneous levels of fluid in the reservoir, and wherein the output feedback signals differ based on whether the temperature signal is within a first temperature range corresponding a first pre-determined fluid fill level or within a second temperature range corresponding to a second pre-determined fluid fill level; and a feedback device communicatively coupled to the control unit to effect an alert based on the feedback signals received from the control unit, wherein one or more parameters of the alert progressively changes as the reservoir fluid level rises.
In another aspect, this disclosure provides in a work vehicle having a system for providing a fluid fill level user feedback alert, in which the system includes: a fluid reservoir configured to receive a fluid up to a pre-determined fluid fill level; a fill level sensor coupled to the reservoir to detect the rising fluid level within the reservoir during filling of the fluid in the reservoir, the fill level sensor configured to output real time fill level signals based on the changing instantaneous level of fluid in the reservoir; a control unit communicatively coupled to the fill level sensor to receive the fill level signals and configured to execute control software to analyze the fill level signals received from the fill level sensor and output feedback signals that are proportionate to the instantaneous levels of fluid in the reservoir; a feedback device communicatively coupled to the control unit to effect an alert based on the feedback signals received from the control unit, wherein one or more parameters of the alert progressively changes as the reservoir fluid level rises; and a user interface coupled to the control unit to display the state of the feedback device and provide user input to set one or more parameters of the alert.
Still other features of the progressive feedback alert system will be apparent from the following description and accompanying drawings.
The following describes one or more example constructions of a progressive feedback fluid fill level alert system 10, as shown in the accompanying figures of the drawings described briefly above. Various modifications to the example construction(s) may be contemplated by one of skill in the art.
The progressive feedback alert system 10 can be used advantageously with any of various types of existing vehicles, including many of the agricultural, construction and forestry machines commercially available from Deere & Co. of Moline, Illinois. For simplicity,
Referring now to
The progressive feedback alert system 10 couples between the hydraulic oil tank 14 and a user interface within the interior (not shown) of the cabin 18. Generally, as shown schematically in
Specifically, with reference to
The details of the example progressive feedback alert system 10 will now be described with continuing reference to
It should be noted that other conventional mechanical or electromechanical devices could serve as the fill level sensor 34, including resistive pad and wiper level sensor mechanisms and reed switch level sensor mechanisms. For example, the fill level sensor 34 can be a reed switch level sensor that consists of one or more reed switches positioned within a stationary non-metallic tube and one or more magnetic elements mounted on a float encircling the stationary tube. As the float rises and falls with the fluid level, the magnetic field generated by the magnets on the float actuates the hermetically sealed magnetic reed switch mounted within the tube which generates a corresponding output signal that can be transmitted to the control unit. Multi-station versions of these sensors allow for multiple level points to be monitored by using a separate reed switch for each level point (such as the pre-determined intermediate fill levels 66, 70 and the maximum capacity fill level 68 discussed below).
The progressive feedback alert system 10 can be configured to monitor a single fill level, such as a maximum capacity fill level 68 corresponding to at or near the full volume of the reservoir, or alternatively some intermediate fill level less than the maximum fill level 68. Monitoring a single fill level would typically suffice for fuel tanks or other reservoirs that hold fluids that do not undergo an appreciable change volume under different operational or environmental conditions. In such cases, the temperature sensor 36 could be omitted, or the control unit 38 could be configured to ignore its output signals.
However, the described example of the progressive feedback alert system 10 is particularly suited to monitor not only a sub-maximal fill level, but also multiple fill levels, which are often needed in reservoirs that hold fluids that expand in volume under working conditions, such as in the manner hydraulic oil expands volumetrically under elevated temperature conditions. Thus, the example progressive feedback alert system 10 can be configured to generate alerts based the desired fill level at different temperatures of the fluid. For instance, the system can provide an alert when the fluid level of the hydraulic oil tank 14 has reached a first pre-determined fill level 66 when the fluid is within a first temperature range as well as when the fluid has reached a second pre-determined fill level 70 when the fluid is within a second temperature range. The fill levels 66, 70 could both be intermediate, or sub-maximal, fill levels, as shown in
The temperature of the hydraulic oil within the hydraulic oil tank 14 is determined by the fluid temperature sensor 36, which can be cantilever-mounted through the rear wall 48 of the hydraulic oil tank 14 to physically extend into the tank cavity 56 in contact with the fluid therein, as shown in
The control unit 38 of the progressive feedback alert system 10 can be a dedicated electronic control unit, or it can be a pre-existing electronic control of the skidder 22, such as the vehicle master controller used to control the overall performance of the engine and vehicle sub-systems, or discreet control hardware for one or more specific sub-systems. The control unit 38 is configured to receive output fill level signals from the fill level sensor 34 and output temperature signals from the fluid temperature sensor 36. The level signal wire 80 and temperature signal wire 84 are communicatively coupled to the control unit 38, thereby delivering the output fill level signals and temperature signals to the control unit 38. The control unit 38 is programmed to execute control software to analyze both the fill level signals received from the fill level sensor 34 and the temperature signals received from the fluid temperature sensor 36 and generate output feedback signals that control the operation of the feedback device 40, which is communicatively coupled to the control unit 38 via suitable dedicated or common electrical lines or system bus 90. The control unit 38 generates feedback signals that are proportionate to the instantaneous levels of fluid in the hydraulic oil tank 14. In addition, the output feedback signals sent from the control unit 38 to the feedback device 40 take into account and can differ depending on whether the temperature signal is within the first or second temperature range, that is whether the hydraulic oil in the hydraulic oil tank 14 is “hot” or “cold.”
In other words, as the hydraulic oil tank 14 is being filled, the fluid level will begin to approach the pre-determined fluid fill levels. Assuming the control software has analyzed the temperature signal received from the fluid temperature sensor 36 as being within the first temperature range, or “cold,” as the fluid level approaches the pre-determined fill level 66, the fill level sensor 34 will generate real time fill level signals as the float of the fill level sensor 34 rises. The control unit 38 executes the control software to analyze the real time fill level signals from the fill level sensor 34 and outputs feedback signals to the feedback device 40 that are proportionate to the instantaneous levels of the fluid in the hydraulic oil tank 14. On the other hand, if the control software has analyzed the temperature signal received from the fluid temperature sensor 36 as being within the second temperature range, or “hot,” the pre-determined fill level 66 will be ignored such that as the fluid level approaches the pre-determined fill level 70, the fill level sensor 34 will generate real time fill level signals as a result of the float rising. Similarly, the control unit 38 executes the control software to analyze the real time fill level signals from the fill level sensor 34 and outputs feedback signals to the feedback device 40 that are proportionate to the instantaneous levels of the fluid in the hydraulic oil tank 14. Once the feedback device 40 begins receiving the feedback signals from the control unit 38, the feedback device 40 effects an alert based on these feedback signals. The feedback signals direct the feedback device 40 to progressively change the alert as the fluid level rises and approaches the pertinent pre-determined fill level 66, 70.
Note that the output feedback signals can, and likely will, differ depending on which of the different pre-determined fill levels 66, 70 (or maximum capacity fill level 68) the progressive feedback alert system 10 is monitoring. This is because a more urgent alert (i.e., higher frequency, amplitude, etc.) will be desired for at instantaneous fill level for the first pre-determined fill level 66, which is at lower tank height and volume and thus will be reached sooner than the second pre-determined fill level 70 (or maximum capacity fill level 68), which is at a higher tank height and volume.
The control unit 38 can be programmed to provide feedback signals to the feedback device 40 that are directly proportionate to the fill level signals from the fill level sensor 34. In other words, for every incremental change in a fill level related parameter, such as fill height, fill volume or fill rate, the control unit 38 can analyze the fill level signals and generate feedback signals to effect a corresponding incremental step change in the output of the feedback device 40. For example, as the hydraulic oil tank 14 is filled and the volume of fluid raises by a Δv, the control unit 38 can direct an audible feedback device to output an alert that is a Δa greater in amplitude, i.e., louder. Such one for one proportional feedback can be provided throughout the entire filling process, or only during a pre-determined portion of the filling process or at select fill levels, such as at lower fill levels.
Alternatively, the control unit 38 can be programmed to provide feedback signals to the feedback device 40 that are indirectly proportionate to the fill level signals from the fill level sensor 34. In this case, during the filling process, or a pre-determined portion thereof or select fill levels, such as higher fill levels, the control unit 38 can analyze the fill level signals and generate feedback signals to effect a change in the output of the feedback device 40 that is related to, but not directly proportional to, the change in a fill level parameter. For example, as the hydraulic oil tank 14 is filled and the volume of fluid raises by a Δv, the control unit 38 can direct the audible feedback device to output an alert that is a Δa +x greater in amplitude (louder). The “x” factor can be a constant value, or it can be a variable that is dependent on another fill level parameter or other exigent parameter, such as a temperature signal from the temperature sensor 36. In this example, the output alert might ramp up in amplitude greater than the incremental Δa step change mentioned above. Again, it could do this during all or only a pre-determined portion of the filling process, for example it could be employed to provide a heightened alert during higher fill levels approaching the pre-determined fill level 66, 70. The “x” factor could also affect an additional characteristic of the feedback device 40, such as in addition to amplitude to also change the frequency or pitch of an audible alert. The “x” factor could also be used to alter the period between each successive alert, either at a disproportionate time constant “t” or at a variable At, including where t=0 such as to effect a constant alert. Thus, in this way, the progressive alert system disclosed herein contemplates systems in which the feedback is both directly and indirectly proportionate to the fill level.
As mentioned, the feedback device 40 can be a separate device specifically dedicated to the progressive feedback alert system 10. Alternatively, the feedback device 40 can be a pre-existing vehicle component or sub-system. Moreover, the feedback 40 device can produce one or more of an audible, visual and tactile response as user feedback of the level of fluid in the reservoir.
For example, the alert generated by the feedback device 40 can be an audible alarm that proportionately increases in frequency and/or amplification as the fluid level in the hydraulic oil tank 14 rises and approaches the applicable pre-determined fill level 66, 70. The audible alert can be, but is not limited to, a beep or tone generated by the skidder's 12 horn or speaker system. Thus, as the hydraulic oil tank 14 is being filled with fluid, the skidder's 12 horn can beep, or the speaker system can generate a sound, for example a beep, tone or music, that gets progressively louder in proportion to the raising fluid level and in the case of a beep or tone can also increase in frequency, in terms of one or both of period and pitch, as the fluid level rises and approaches the applicable pre-determined fill level 66, 70 (or maximum capacity fill level 68).
As another example, the alert generated by the feedback device 40 can be a visual alert that proportionately increases in frequency and/or luminescence as the fluid level in the hydraulic oil tank 14 rises and approaches the pre-determined fill level 66, 70 (or maximum capacity fill level 68). The visual alert can be, but is not limited to, a light generated by an indicator light inside the cabin 18, or an exterior light such as the skidder's 12 work light, running lights, blinkers or headlights. As the hydraulic oil tank 14 is filled with fluid, the skidder's 12 light will generate a flash of light that gets progressively brighter and more frequent proportionately to the rising fluid level as it approaches the pre-determined fill level 66, 70 (or maximum fill level 68).
Thus, as mentioned, the alert generated by the feedback device 40 can be solely an audile alert, solely a visual alert, or a combination of both. And although not part of the aforementioned examples, a tactile feedback could be generated using a dedicated vibratory device that would vibrate a part of the vehicle. As described for the audible and visual alerts, the tactile alert can be generated to progressively increase in frequency and amplitude in proportion to the rising level of fluid in the reservoir.
The progressive feedback alert system 10 can also be configured with respect to the initiation and termination of the alert. Specifically, the progressive feedback alert system 10 can be configured to only activate the feedback device 40 upon reaching a threshold fill level, such as with a prescribed fill level below the applicable pre-determined or maximum fill level, for example when the fluid reaches 80% of the desired fill level. The progressive feedback alert system can be configured to activate upon reaching such a single threshold fill level regardless of whether there is a temperature input or whether it is taken into account to generate the feedback signals to the feedback device 40, as described above. Alternatively, there can be multiple threshold fill levels that the control unit 38 analyzes before initiating the alert. As an example, a first threshold fill level may correspond to 80 percent of the first pre-determined fill level 66, which is at a lower tank height and volume than for the second pre-determined fill level 70 (or maximum capacity fill level 68), which is at a higher tank height and volume and thus could have a second threshold fill level, corresponding to 80 percent of the second pre-determined fill level 70. Of course, each threshold fill level could be based on different percentages of full or other parameters related or unrelated to the pre-determined fill levels.
Additionally, once the fluid reaches the applicable pre-determined fill level 66, 70 (or maximum capacity fill level 68), a distinct change in the alert could be effected, including becoming a steady state constant or alternating feedback. For example, in the case of a visual alert, the light can become a solid, bright light, indicating to the user to stop filling the hydraulic oil tank 14, or for an audible alert, it can become a solid beep or tone. Or one type of alert, such as an audible only alert, could be alternated or combined with one or more other types of alerts, such as visual alert. Still further, other stimuli could be effected to get the user's attention such as by activating other sub-systems of the vehicle, for example, flashing the screen of the user interface or activating operator seat controls, window controls or door locks.
Like the other components, the user interface 42 of the progressive feedback alert system 10 can be a system-dedicated monitor or display panel, or it can incorporate the pre-existing vehicle operator interface display mounted in the cabin 18, for example a display interface such as the T7000 tablet commercially available from Mobile Demand of Hiawatha, Iowa. In either case, the user interface 42 is coupled to the control unit 38 via suitable electrical wires or bus 92 to give the vehicle operator an electronic display of the actual fill level in the hydraulic oil tank 14 as well as the fill levels of other vehicle fluids, such as fuel. The user interface 42 also allows the operator to readily enable, disable or check the state of activation of the progressive feedback alert system 10. It can also provide user input of one or more settings of the system, thereby allowing the operator to easily adjust various parameters of the alert system. For example, and without limitation, a vehicle operator can use the user interface 42 to select the type of alert, such as any one or combination of an audible, visual and tactile feedback response, and specific formats of each type, such as to activate the work light or the headlights, or to generate a tone, beep or play music. The user interface 42 could also be used to adjust parameters such as period frequency, pitch frequency and volume of audible alerts, the brightness and flashing frequency of visual alerts, and the frequency and amplitude of tactile alerts.
The foregoing detailed description describes the subject of this disclosure in one or more examples. A skilled person in the art to which the subject matter of this disclosure pertains will recognize many alternatives, modifications and variations to the described example(s). The scope of the invention is thus defined not by the detailed description, but rather by the following claims.
