Patent Publication Number: US-2022234424-A1

Title: System and method for idle mitigation on a utility truck with an electrically isolated hydraulically controlled aerial work platform

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The present application is a continuation application of the non-provisional patent application having Ser. No. 15/700,301 filed on Sep. 11, 2017, which non-provisional application claims the benefit of the filing date of provisional patent application having Ser. No. 62/385,350 filed on Sep. 9, 2016 by the same inventor, and the provisional application having Ser. No. 62/396,452 filed on Sep. 19, 2016, which applications are incorporated herein in their entirety by this reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention generally relates to utility bucket trucks with insulated aerial work platforms, and more particularly relates to idle mitigation systems for use on insulated bucket trucks with hydraulic in-the-bucket controls. 
     BACKGROUND OF THE INVENTION 
     In the electrical and telecommunications industries, elevated work platforms (EWPs), such as aerial devices, are commonly used to position personnel for work on utility lines, utility poles, transformers, and other elevated equipment. 
     Such devices are also used for a range of other applications such as tree trimming, photography, and street and spotlight maintenance. These devices typically include a telescoping and/or articulating boom mounted on a truck bed or otherwise supported by a vehicle chassis. A personnel-carrying platform, also referred to as a bucket or basket, (which is often electrically isolated from the ground to protect the occupant from electrocution) is attached to a portion of the boom distal the vehicle chassis (i.e., the boom tip). Using a control interface located at the platform, for example, an operator may adjust the rotation, extension and articulation of the boom to best position the platform for access to a work site. 
     These trucks typically have a low duty cycle of hydraulic usage during a work day. 
     To preserve the ability to have full on demand access to hydraulics and/or air conditioning, these trucks are often left idling much of the day. 
     These trucks are often left idling much of the day to provide cabin comfort such as air conditioning. 
     Grip idle management system is an off-the-shelf system that is well known in the art and is effective in some applications. 
     U.S. Pat. No. 9,216,628 provides an idle management system which requires two air conditioning compressors and a need to tap into the refrigerant lines in the vehicles air conditioning system. 
     Consequently, there is a need for improved air conditioned and idle managed trucks with on-demand hydraulics. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide alternative cab comfort operation when the engine is off without the need for a second air conditioning compressor and the need to tap into the vehicles refrigerant lines. 
     It is a feature of the present invention to include an alternate source of rotary power for driving an air conditioning compressor. 
     It is an advantage of the present invention to not require two air conditioning compressors and a need to tap into the refrigerant lines in the vehicles air conditioning system. 
     It is another object of the present invention to add the ability to provide increased rates of charging of a battery for auxiliary hydraulics and air conditioning without significant additional expense. 
     It is another feature of the present invention to utilize components of the alternate source for rotary power to drive the air conditioning compressor to charge the battery for the auxiliary hydraulics and the auxiliary air conditioning. 
     It is another advantage to reduce costs of an additional rapid charging capability. 
     It is still another object of the present invention to provide automatic operator initiation vehicle engine start-up commands without the addition of new communication equipment in the bucket. 
     It is still another feature to use a sensed increase in hydraulic pressure at the truck to determine that an engine start is needed. 
     It is still another advantage to avoid the need of adding RF or fiber optic communication equipment in the bucket. 
     It is yet another object of the present invention to improve consistency of hydraulic performance during times when vehicle engine is transitioning between off and on operational states. 
     It is yet another feature to provide increased pressure sensing and regulating capabilities for the hydraulic lines. 
     It is yet another advantage to improve safety by providing hydraulic bucket controls which are smooth and consistent during engine transition stages. 
     It is a further object of the present invention to reduce cost of an idle management system for air conditioned bucket trucks. 
     It is a further feature of the present invention to provide for prioritized timely sharing of auxiliary drive power for hydraulics and air conditioning. 
     It is a further advantage to eliminate the need for a separate electric motor to drive the auxiliary hydraulic pump and the auxiliary drive for the air conditioning compressor. 
     It is even a further object of the present invention to improve efficiency of an idle management system. 
     It is even a further object of the present invention to utilize operator-in-the-cab detection information and operator-in-the-bucket detection information. 
     It is even a further advantage of the present invention to automatically adjust commanded inside cabin temperature when an operator is detected in the bucket and not in the cab. 
     The present invention is designed to achieve the above-mentioned objects, include the previously stated features, and provide the aforementioned advantages. 
     The present invention is carried out in a dual air conditioning compressor-less system in the sense that only a single air conditioning compressor is required. 
     The present invention is carried out in a dual alternator-less system in the sense that an alternate source of charging batteries for the auxiliary hydraulics system and the auxiliary air condition system is accomplished without the need to add an additional alternator to the vehicle. 
     The present invention includes: 
     A method associated with an idle managed and air conditioned truck-mounted aerial work platform, the method comprising the steps of:
         providing a first source of rotary power for driving an air conditioning compressor, where said first source of rotary power has a first connection with an engine of a vehicle;   providing a second source of rotary power for driving the air conditioning compressor on the vehicle;   driving a hydraulic pressure generator which has a first electrical connection to a source of stored electric energy;   causing said second source of rotary power for driving the air conditioning compressor to drive said air conditioning compressor when said first source of rotary power for driving the air conditioning compressor is unavailable; and   said second source of rotary power for driving said air conditioning compressor is configured to utilize said first source of rotary power for driving the air conditioning compressor, when said engine of the vehicle is running, to charge said source of stored electric energy.       

     The present invention also includes: 
     A method associated with an idle managed and air conditioned truck-mounted aerial work platform, the method comprising the steps of:
         providing a first source of rotary power for driving an air conditioning compressor, where said first source of rotary power has a first connection with an engine of a vehicle;   providing a second source of rotary power for driving the air conditioning compressor on the vehicle;   driving a hydraulic pressure generator which has a first electrical connection to a source of stored electric energy;   causing said second source of rotary power for driving the air conditioning compressor to drive said air conditioning compressor when said first source of rotary power for driving the air conditioning compressor is unavailable; and   said second source of rotary power for driving said air conditioning compressor is configured to utilize said first source of rotary power for driving the air conditioning compressor, when said engine of the vehicle is running, to charge said source of stored electric energy.       

    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic view of a system of the present invention. 
         FIG. 2  is a simplified schematic diagram of a data communication relationship and operational logic configuration which could be used with a system as shown in  FIG. 1 . 
         FIG. 3  is an additional depiction of an operational configuration of an embodiment of the present invention. 
         FIG. 4  is an additional depiction of an operational configuration of an embodiment of the present invention which relates to temperature of a battery during a charging process. 
         FIG. 5  is an additional depiction of an operational configuration of an embodiment of the present invention relating to control of restarting after a shutdown. 
         FIG. 6  is a schematic representation of an alternate rapid recharging embodiment of the present invention. 
         FIG. 7  is a schematic representation of a portion of the present invention shown in  FIG. 6  but with a first fluid flow path. 
         FIG. 8  is a schematic representation of the same portion as shown in  FIG. 7  but with a second fluid flow path. 
         FIG. 9  is a more detailed schematic representation of hydraulic portions of the present invention. 
         FIG. 10  is a detailed schematic view of a battery management system of the present invention, which provides information including safety information for a particular embodiment of the present invention. 
         FIG. 11  is a detailed schematic representation which relates to desired cab temperatures based upon operator presence in the cab. 
         FIG. 12  is a spatial representation of the proper orientations of  FIGS. 12A-12C  which are in combination an overall decision matrix on how the present invention could be made to operate. 
         FIGS. 13-38  are schematic representations of operation parameters of the present invention. 
         FIGS. 39-42  show representations of an actual implementation of portions of the present invention. 
         FIG. 43  represents the bucket truck of the present invention. 
         FIGS. 44-45  show tables for additional duty cycle information. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Now referring to the drawings, wherein like numerals refer to like structure shown in the drawings and text included in the application throughout. The description below is directed to hydraulically controlled and air conditioned bucket trucks but the benefits of the present invention are applicable to vehicles which are equipped with on-demand hydraulics which are not bucket trucks and to air conditioned vehicles of all types. The following detailed description is intended to be an example of the many possible uses for the present invention. The invention described in detail below is for the purpose of illustration, it is to be understood that such detail is solely for that purpose and that variations can be made therein by those of ordinary skill in the art without departing from the spirit and scope of the invention as defined by the following claims, including all equivalents thereof. 
     The present invention in one embodiment is a bucket truck as shown in  FIG. 43  which is built on a commercially available truck chassis such as a Dodge 5500 but any appropriate truck chassis could be used. In the past, it has been well known to start the manufacture of a bucket truck with such a factory built road-ready vehicle. Many components such as the boom and the bucket have been added to the OEM chassis to make a finished bucket truck. 
     Now referring to  FIG. 1 , there is shown a schematic representation of a portion of the present invention. The upper right portion of this figure is the preferably unchanged OEM truck air conditioning system  10 . Immediately below this is a representation of more unchanged OEM truck components but also mixed with new components. In one embodiment, the following components below the system  10  in the figure are unchanged OEM components:  20 ,  22 ,  24 ,  26 ,  28 ,  40 , and  13 . Everything in the figure to the left of the air conditioning compressor  152  is not a part of the OEM chassis except for the following components:  40  (however it could be ordered with the chassis). Note that tank  126  is included not with the chassis but with what is found in other hydraulic bucket trucks. 
     The present invention may begin with the OEM chassis with a commercially available idle management system having been added to it such as one made by grip idle management. 
     The present invention attempts to provide the operator in the bucket, at a time when the engine  20  is not running, with the ability to initiate the operation of the hydraulic controls  42  in the bucket by merely grasping them and manipulating them in the normal manner for operation of these controls. To accomplish this ability when the engine  20  and therefore the PTO pump  40  are not running, an electric auxiliary hydraulic pump  120  is included which provides hydraulic pressure to the pressure lines  42  of the hydraulic system which would run to and from the hand controls in the bucket. In a prior art bucket truck, the PTO pump  40  would be coupled directly to lines  42  and would provide the needed hydraulic pressure and flow to the bucket to provide typical functions when the engine is running. 
     In the present invention, the auxiliary hydraulic pump  120  is used to provide hydraulic pressure together with electric motor  110 , and controllers  130  and  134 . In general, the pressure transducers  121  and  124  detect when the PTO  40  is off and a demand is applied to the system through the system  42  (e.g. manipulation of the control handles in the bucket). A more thorough understanding of the hydraulic portions of the present invention can be achieved by utilizing details shown in  FIG. 9 . The capacity of the auxiliary battery  162  limits the amount of time that the electric motor can run without being recharged. See  FIG. 10  for more details on battery. 
     Returning now to  FIG. 1 , when it is necessary to turn the engine  20  back on, the transition needs to be made so that the operator in the bucket truck does not experience problems with lag or excess flow, etc. (lag or overspeed of the boom). The transition could function as follows: When the engine  20  is deactivated by the idle management functions, the mechanical PTO pump  40  is deactivated while the auxiliary pump  120  is in standby mode. 
     This provides the system with low flow—low pressure. When the operator demands movement by activating the hydraulic valves  42 , a load is detected by an increase in the pressure of the working fluid by pressure transducer  121 . The controllers  130  and  134  of the system signals the electric motor  110  to provide maximum flow. The auxiliary pump  120  is then responsible for full movement and a signal is sent via line  135 , controller  136  and a line to the engine  20  to start. During this transition, the engine responds and achieves designated RPM, the mechanical PTO  40  is activated and provides an additional flow. By monitoring the pressures ( 121  and  124 ) of the mechanical PTO  40  and auxiliary pump  120 , the system then signals the electric motor  110 , which causes the auxiliary pump  120  to deactivate so the boom speed is maintained. 
     Consequences of shutting the auxiliary pump  120  off too early or late are a change in boom speed. Testing shows the auxiliary pump  120  needs to be deactivated within 50 milliseconds. Too late and the boom over speeds, too early and the boom movement lags. 
     The engine  20  will initialize shutdown upon two conditions—a load is not detected  124  in the working fluid and the predetermined engine run time has exceeded. If no load is detected, the engine  20  is shutdown with the goal of reducing idle time. If a load is detected  124  while the engine  20  is being deactivated, the controller is triggered by a percentage of the prior engine speed and detection of a pressure greater than the low state pressure created by the mechanical PTO. The auxiliary pump is activated and is responsible for full flow of the working fluid. 
     The percentage drop in RPM before the system responds is roughly 4%. The system needs to respond to roughly 5% change in low state pressure. This provides an adequate response for the pump to build the pressure and flow required. 
     Now referring to  FIG. 2 , there is shown detail relating to the standby and operational speeds of the electric motor ( 110 ). Based on PTO pump pressure ( 123 ) and ePump Pressure ( 121 ) will determine the state of the electric motor for motor speed low ( 110 ), motor speed high ( 110 ). If the motor speed ( 110 ) and ePump Pressure ( 121 ) meet the criteria, the truck engine will start ( 136 ) and the electric pump speed will change to “off” based on the PTO pump pressure ( 124 ). The truck engine can also be started ( 136 ) when the Ba:MD3[0] ( 162 ) falls below the low battery level ( 141 ). 
     Now referring to  FIG. 3 , there is shown details relating to the charging rates of rated torque ( 110 ) and actual velocity ( 110 ) can be varied to change to the charging rate of the electric motor. Inverter temp ( 134 ) and battery voltage ( 162 ) are monitored to ensure safe charging conditions. 
     Now referring to  FIG. 4 , there is shown a representation of factors involved in regulating charging of a battery based upon temperature of that battery. 
     Now referring to  FIG. 5 , there is shown a representation of factors including dwell time involved in controlling restarting the engine after a shut down. 
     During times that the engine  20  is off, the auxiliary battery controllers  130  and  134  drive the electric motor  110  which has mechanical connection to BOTH the auxiliary hydraulic pump  120  and the hydraulic motor  100 , which the three in combination can be viewed as a tandem hydraulic pump  125 . This eliminates the need for a separate electric motor for auxiliary hydraulics and auxiliary air conditioning. An air conditioning compressor clutch  150  which couples the mechanical rotary power being supplied to the air conditioning compressor  11  from the normal belt  24  in the vehicle air conditioning system to the belt  151  and pulley driven alternately by the electric motor  110 . 
     This configuration allows for operation of the air conditioning system without the need for changing anything in the vehicle air conditioning refrigerant system including items  11 - 16 . 
     Now referring to  FIG. 6 , there is shown an alternate version of the present invention which provides for the ability to charge and/or increase the rate of charging the auxiliary battery  162  without using capacity from the alternator  40  and/or without the need to add an additional alternator. Instead, the electric motor  110  is driven backwards to generate a DC charging current to the auxiliary battery  162 . 
     The electric motor  110  is driven backward when the vehicle engine  20  is running and the air conditioning compressor  17  is turning and the motor clutch  150  is engaged causing the hydraulic motor/pump  127  to turn. A valve  820  is included between the existing tank  126  and the hydraulic pump  127 , when closed the valve  820  blocks flow in one direction while permitting flow in the opposite direction. When the valve  820  is open, fluid is free to move in either direction. 
     The hydraulic pump  100  would be caused to turn in an opposite direction from the direction it turns when the auxiliary battery  162  is used to turn the air conditioning compressor  17 . The hydraulic motor  100  then turns the electric motor  110  and provides power for charging the auxiliary battery  162 . 
       FIGS. 7 and 8  show the direction of flow around the fluid path defined by the pump  127 , hydraulic motor  100  and valve  820 . When the valve  820  is closed, ( FIG. 8 ) the direction of flow reverses and the hydraulic motor  100  is turned in reverse. In  FIG. 6 , there is shown a clutch  810  between the electric motor  110  and the hydraulic pump  120  which, in normal operation of the idle management system is used to provide an alternate source of hydraulic pressure for the PTO system of the vehicle during engine off times. An electronic control line  800  to the clutch  810  switches (on and off) the connection between the electric motor  110  and the hydraulic pump  120 . Also shown is an electronic control line from control  130  to valve  820 . 
     The result is that without the need for another alternator, the auxiliary battery is charged at a much higher rate than in the original system of  FIG. 1 . The DC charger  163  and the connection to the alternator  40  could be left in place or removed. 
       FIGS. 9 and 10  are included to provide more specific details of a particular embodiment of the invention as mentioned above. 
     Now referring to  FIG. 11 , there is shown a detailed representation showing that the auxiliary air conditioning system can be turned on based on items  161 ,  150 ,  136 ,  125  and  20 . Item  138  will vary the desired temperature setting based on the operator presence in the cab, bucket or in a certain proximity to the machine. Using this setting, difference in cab temperatures can be adjusted to achieve the maximum operator satisfaction versus energy consumed to cool the cab. 
     Now referring to  FIG. 12 , there is shown a spatial representation of the proper orientations of  FIGS. 12A-12C , which are in combination an overall decision matrix on how the present invention could be made to operate. 
     Now referring to  FIG. 13 , there is shown a schematic representation of details relating to how “E-pump delay off” is used to determine when the electric motor needs to shut down. This parameter is needed to keep constant motion on the bucket to not over or under speed the boom since the total flow to the boom is a combination of the PTO pump and electric motor/pump output. 
     Now referring to  FIG. 14 , there is shown a schematic representation of details relating to how “Air Conditioning Motor Speed High” is used to determine the operational condition of the electric motor to match the desired compressor speed used to cool the cab. This parameter is updated in real time to maximize the overall cooling performance while minimizing the energy consumed. 
     Now referring to  FIG. 15 , there is shown a schematic representation of details relating to how “Motor Speed High” is used to achieve the desired output of the electric pump to match the boom performance of the PTO pump. 
     Now referring to  FIG. 16 , there is shown a schematic representation of details relating to how “Motor Speed Low” is used to determine the standby speed to minimize the power consumption when the boom is not in use. This speed must allow the pump to build pressure to ensure no noticeable lag to the operator when boom functionality is required. 
     Now referring to  FIG. 17 , there is shown a schematic representation of details relating to how “High PSI kick in” is used and that when boom operation is required, this parameter sets the requirement for when the electric pump needs to be at operational speeds. 
     Now referring to  FIG. 18 , there is shown a schematic representation of details relating to actively monitoring the pressure output of the electric motor. 
     Now referring to  FIG. 19 , there is shown a schematic representation of details relating to how “Start Motor” uses various inputs to determine when the auxiliary air conditioning or hybrid boom operation is required. This parameter also sets the condition when the motor should be shutdown. 
     Now referring to  FIG. 20 , there is shown a schematic representation of details relating to how “Motor Speed” is taking various input to determine if the operation or standby motor condition is required by the electric motor. 
     Now referring to  FIG. 21 , there is shown a schematic representation of details relating to how “PTO Pump” is used to determine the conditions when the PTO pump is fully active and leading to the ability to shut down or start up the electric motor. 
     Now referring to  FIG. 22 , there is shown a schematic representation of details relating to how “Run HP TMR” sets the requirement of how long the pressure signal needs to be high before the system will respond, it also sets the requirement of when high pressure conditions should be ignored. 
     Now referring to  FIG. 23 , there is shown a schematic representation of details relating to how “Motor Speed Command” is used to determine the appropriate “Speed Command” of the electric motor. 
     Now referring to  FIG. 24 , there is shown a schematic representation of details relating to how “Ok to Charge” is using inputs to determine if the system is in an acceptable condition to activate charging. 
     Now referring to  FIG. 25 , there is shown a schematic representation of details relating to how “Low Pressure Timer” is used to determine the required time the system needs to see low pressure before it responds. 
     Now referring to  FIG. 26 , there is shown a schematic representation of details relating to how “E-pump off Run Time” is used to actively set the desired time the system needs low pressure before the electric motor speed is changed. 
     Now referring to  FIG. 27 , there is shown a schematic representation of details relating to how “Enable cab comfort” is used to determine the conditions when cab comfort operation is required. 
     Now referring to  FIG. 28 , there is shown a schematic representation of details relating to how “Node  2  Torque Scaled” is used to determine the desired torque output of the electric motor, this can be adjusted to decrease power consumption. 
     Now referring to  FIG. 29 , there is shown a schematic representation of details relating to how “Node  2  Velocity Scaling” is used to set the velocity to all positive since the system can run the electric motor in positive or negative direction. 
     Now referring to  FIG. 30 , there is shown a schematic representation of details relating to how “Average Bat Temp (° F.)” is used to determine safe operating or charging conditions of the battery. 
     Now referring to  FIG. 31 , there is shown a schematic representation of details relating to how “DC Charger enable IDC” enables the output to activate the charging conditions. 
     Now referring to  FIG. 32 , there is shown a schematic representation of details relating to how “Engine hold at zero speed” holds the engine in the off state for a determined time before it can be restarted. 
     Now referring to  FIG. 33 , there is shown a schematic representation of details relating to how “A/C high PSI tmr” is used to ensure safe start conditions when the air conditioning system pressure is below a certain threshold. 
     Now referring to  FIG. 34 , there is shown a schematic representation of details relating to how “Min A/C PSI to start” is used to provide air conditioning compressor protection in the event of a system leak or failure. 
     Now referring to  FIG. 35 , there is shown a schematic representation of details relating to how “Want cab Comfort IDC” is used to determine the auxiliary air conditioning operation based on the presence of an operator. 
     Now referring to  FIG. 36 , there is shown a schematic representation of details relating to how “Run A/C” is used to activate or deactivate the auxiliary air conditioning system based on operational conditions if the engine is started or the system pressure is too high. 
     Now referring to  FIG. 37 , there is shown a schematic representation of details relating to how “Run Comp fan IDC” is used to determine the operational conditions of the air conditioning condenser fan. This is varied to maximize system performance while minimizing energy consumption. 
     Now referring to  FIG. 38 , there is shown a schematic representation of details relating to how “Start the truck” uses various parameters to determine if the truck engine is required to be activated. 
     Now referring to  FIGS. 39-42 , there is shown representations of an actual implementation of portions of the present invention. 
     Now referring to  FIG. 43 , there is shown a bucket truck of the present invention. 
     Now referring to  FIGS. 44-45 , there is shown tables indicating additional duty cycle information. 
     One embodiment of the present invention includes the ability to conserve electric power consumed by the electric motor  110  and also can reduce idle time if the presence of the operator is detected by OPS  138  and/or by a similar device inside the bucket and during time when there is no one in the cab of the vehicle and there is someone in the bucket, the normally set cab temperature can be used upwardly for air conditioning and downwardly for heat by a preset amount, for example 20 degrees Fahrenheit. This will allow for less running of the engine and less running of the electric motor  110  but can then command the normal temperature once the operator presence is detected or the operator is detected as having exited the bucket. 
     Another embodiment of the present invention allows for improving the constancy of the operation of the hydraulic bucket controls during times when the vehicle engine is in transition from off to on and on to off. The pressure sensor can detect e.g. an increase of pressure generated by the PTO pump  40  during start up and can provide a signal to the controller  130  which can immediately reduce the pressure generated by pump  120 . This leveling or maintaining of a constant pressure results in a more constant, smooth and predictable operation of the movement of the manipulation of the bucket. 
     In yet another embodiment of the present invention, the use of the output of electric motor  110  can be shared on a prioritized basis to reduce a need for oversized or dual electric motors. It is contemplated that the hydraulic controls could in some instance be given a priority over air conditioner operation to reduce the need for such oversized electric motors. 
     It is thought that the method and apparatus of the present invention will be understood from the foregoing description, and that it will be apparent that various changes may be made in the form, construct steps, and arrangement of the parts and steps thereof, without departing from the spirit and scope of the invention, or sacrificing all of their material advantages. The form herein described is merely a preferred exemplary embodiment thereof.